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(Last updated 9 Apr 2011.)
Download the library.
Table of contents:
In most systems the default allocator used by C++ (and C) compilers is a very general memory allocator which supports allocating and freeing blocks of memory of any size. The advantage of this is that it's memory-efficient when the sizes of the allocated blocks are very varied throughout the execution of the program.
The disadvantage of this is, however, that the bookkeeping data needed by the default allocator is relatively complicated, so managing all this memory with free-sized blocks is relatively slow. Another problem is that the default allocator tends to be rather cache-unfriendly with repeated allocations and deallocations, as the list of freed blocks gets quite randomized (a very random list of free memory blocks will cause allocations to cause large amounts of cache misses, which can heavily penalize the speed of the allocator).
There are many situations, especially when programming in C++ using the STL data containers, where it would be enough to have an allocator for fixed-sized memory blocks. The advantage of this is that the allocator can be made considerably faster because the bookkeeping is much simpler and it's much easier to make it cache-friendly.
This library provides two allocators which are more optimized for
speed and memory usage. The first one is especially suitable for the
C++ STL data containers, specifically
This library presents two fixed-size block allocators:
This is a more generic fixed-size block allocator, which is very
suitable for use with the C++ STL data containers which allocate one
element at a time, ie.
std::map. It cannot be used with
std::string (but on the other
hand the memory usage of those containers is already very good, so they
don't really need a specialized allocator).
The allocator works by allocating contiguous blocks of memory where the allocated elements are stored. The size of the element is determined automatically from the objects to be allocated. Basically an allocator is created for every element size that is used. (On the other hand, if two different data containers use elements of the same size, they will share the same allocator.)
If an entire block of elements is deallocated, then the block will be freed from the main memory as well. Besides the obvious advantage of memory being freed for other uses, this has also speed advantages (because if the block is allocated again, it will be cache-friendly and consecuently very fast).
Each allocated element has an overhead of 4 bytes in 32-bit systems
(8 bytes in 64-bit systems), which is the same as with most default
memory allocators. Thus this allocator does not consume any more memory
than the default one. In fact, it can sometimes allocate even less memory
than the default allocator because many such allocators align allocated
elements to 8-byte boundaries, while
to 4-byte boundaries (in 32-bit systems).
The disadvantages of using this allocator are the following:
std::deque). On the other hand, this is usually not a problem.
This is very similar to the
FSBAllocator, with the difference
that it never frees memory. The advantage of this is that no bookkeeping data
is needed, and thus there's no overhead and allocated elements take only
as much memory as the size of the element.
This can be especially efficient if lots of very small elements
(such as individual integers) are allocated. For example the default
memory allocator in Linux allocates a minimum of 16 bytes per element,
so if you allocate an individual (4-byte) integer, 16 bytes will be
allocated nevertheless. Using
FSBAllocator2 only 4 bytes will be
allocated (in 32-bit systems).
The disadvantage over
FSBAllocator is that since memory is
never freed, this memory cannot be used by anything else and, more
FSBAllocator2 can be considerably slower than
FSBAllocator when lots of elements are constantly being
allocated and freed. (As mentioned earlier, if the list of freed elements
gets very randomized, this will cause the allocator to become
cache-unfriendly, causing lots of cache misses, which can penalize it
in speed quite a lot.)
Note, however, that according to my tests
is basically never slower than the default allocator, and thus safe to use
Only if all the allocated elements are freed, then
FSBAllocator2 will release all of its memory, becoming
(for the time being) cache-friendly and fast again.
FSBAllocator2 also has a special function for freeing
blocks of memory which only contain deallocated elements. This function
performs a linear sweep through all the blocks and deallocates the ones
which do not contain allocated elements, as well as making the list of
free elements linear. While this sweep can be slow, it will make
subsequent allocations faster.
This allocator is especially efficient for allocating very small elements, such as for example smart pointer reference counters. Details about this are given later in this document.
Note that in simple circumstances
FSBAllocator2 can be
even faster than
FSBAllocator. (For example if memory is
only allocated during the execution of the program, and only freed all
at the same time at the end.)
FSBAllocator2 can be used with the STL containers in the
same way as
FSBAllocator, but due to its speed issues this
should only be done if the memory savings are important or in simple
cases, like the above.
The same disadvantages apply as with
To test the speed of
FSBAllocator compared to the default
allocator used by the compiler, the following test was performed on a Linux
system using gcc 4.1.2 on a Pentium4 3.4GHz:
std::list was used, and the following operations
where done to it:
This process was repeated in a loop 10 times.
The benchmark was run for both the default allocator and the FSBallocator.
For comparison, this test was also run using
boost::fast_pool_allocator. All conditions were otherwise
exactly identical. The results were:
FSBAllocator: 16 seconds.
The same test was repeated using
insert() instead of
and the results were:
FSBAllocator: 1 minute 10 seconds.
(Note that in this case there are far fewer element creations and deletions because of all the repeated values, which is the reason why the times are closer to each other.)
Using the allocator is rather simple. Simply
_TAG_ "FSBAllocator.hh" in the source files where
the allocator is used, and then simply give the allocator to the desired
STL container as template parameter. For example, instead of writing this:
std::list > aList;
That's it. No other modifications are needed.
The same for
std::set would be:
std::set, FSBAllocator > aSet;
If you want to use the allocator directly, as a replacement of
delete, it can be done like this:
FSBAllocator alloc; YourType* anInstance = alloc.allocate(1); // alloc.construct(anInstance, YourType()); // if YourType is a class... // alloc.destroy(anInstance); // if YourType is a class alloc.deallocate(anInstance, 1);
allocate() only allocates memory for the object
but doesn't initialize it in any way (similarly to how, for example,
std::malloc() would do). If your type is a class, you'll have
to initialize and destroy it yourself as demonstrated in the commented
lines or by using placement new directly after allocating and by
calling its destructor explicitly before deallocating.
(Also note that, as stated earlier, arrays cannot be allocated with this allocator, and thus the only valid parameter value is 1.)
FSBAllocator2 can be used in the same way as
FSBAllocator, although usually it's only recommended for
special cases, like for example as a reference counter pool, described below.
FSBAllocator2 offers a special function for
freeing unused memory, which can be used like this:
This will make the allocator to traverse all the allocated blocks and free the ones which do not contain any allocated elements. It will also make the list of freed elements linear.
Note, however, that there's a catch, which can make this function to
malfunction, and thus it must be used with care: In order to distinguish
which allocated elements are free and which aren't, it fills these freed
elements with an "unused value", which it takes as parameter, and which
by default is a
size_t(-1). This value must indeed by
unused by the application. If the application has written this value
in some of the allocated elements, this function will malfunction (and
free elements it shouldn't).
For example if this allocator is used as a reference counter pool,
and all reference counts get values greater or equal to 0, then it's
safe to call this function as it is. If the value
is used by the application for something, then it must provide some other
unused value for this function to use, for example:
If unsure, it's better to not to call this function at all.
Note, however, that even though this function can be slow (depending on how much memory has been allocated), it can make subsequent allocations much faster, especially if the list of freed elements has become very randomized.
By default this library is not thread-safe, and thus cannot be used as an allocator for multiple threads. (As long as only one thread uses this allocator and the memory allocated by it, it should be ok.)
The library offers several possibilities for making itself thread-safe. This is done


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At Harbin Siberian Tiger Park, feeding time is a spectator sport.
Now home to more than 1,000 tigers, the park, located in northern China, is one of the world's largest and most successful conservation parks for the endangered animals. The park, which was intended to be a sanctuary and breeding center, now is a stop for many excited tourists.
(PHOTOS: Animals That Can Think)
At the park, patrons can now (for a fee) watch Siberian tigers be fed live animals. On a visit, patrons are able to choose from a menu — the animals they wish to see fed to the tigers. Current rates according to the Today show, run $8 USD for a chicken, $90 for a sheep and $300 for a cow.
The graphic scenes of tigers feeding on live prey have become popular on YouTube, amplifying awareness of this particular practice.
Park patrons view the scene from what the park calls the "Number One Adventure Bus." One incident this past January resulted in the death of one of the bus drivers. The driver was killed after being dragged off by one of the park's tigers in an attempt to check the bus's engine.
Reactions have varied from praise for the park's efforts to protect the endangered tigers (there remain approximately 20 in the wild in China) to outrage on the part of those who question whether or not the Harbin Siberian Tiger Park is making a spectacle out of conservation.
(VIDEOS: 12 Bizarre Animal Friendships)

source: HuggingFaceFW/fineweb-edu


text:
I understand that one way to generate clones is to fuse live cell donors with enucleated oocytes. This obviously would not work since the frozen cells would not have viable cell walls.
My interpretation of how the authors successfully cloned these mice goes as follows, is this correct?
-Attempted to inject frozen donor neuronal nuclei into enucleated oocytes, did not take
-Injected frozen donor neuronal nuclei into stem cells, they took. Injected those stem cells into blastocyst to generate chimeras which were then mated until clone was formed.
If this is correct, any idea why the stem cells took while the oocytes did not? The authors did not talk about this in the discussion.
Edited by Ahrenhase, 14 May 2011 - 10:21 AM.


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The Curious tale of Z and Cedilla.
Our modern cedilla symbol begun life as a "scribal ligature" which in plainer words means two characters combined into one by scribes as a kind of shorthand. The sounds cedilla represents in Roamnce language in one stage were written cz and had a Spanish nickname of cedilla or zedilla - the litte zeta. Originally the sound was probably "ts" and later became a "sh" sibilant sound partly due to the large number of Arabic and Hebrew speakers in Spain during the Islamic era.
It has been or is used in Spanish, Portugese, Catalan, Friuli and Occitan.
Beyond Europe it was adopted by several languages of the Turkkic family when they switched from Arabic and Cyrillic to Roman alphabets, Osmanli also known as Ottoman, Azeri, Tatar, Turkmen, and others.
While usuallu representing a sibilant one European Langaue Latvian uses it to mark Palatals to distinguish them from Velars and Nasals so it appears under g, K, L, and N.
Its use was much more common before IPA fonts were available.

source: openbmb/Ultra-FineWeb


It is "actually."
For the experienced listener, "actually" is a dead giveaway of an area that at the least needs to be further investigated, and may point at a deception.
Let me explain. When you use the word "actually" properly, you are comparing two thoughts and providing clarification.
For example:
Question: "Did you go to the store for milk?"
Answer: "Actually, I stopped at a gas station."
Back to the business setting: Extra words used in a sales presentation or investor pitch are unnecessary. They subconsciously point listeners to question if there's more unspoken information. The word "actually" serves as a spoken pause, giving the presenter's brain time to catch up and decide how to resolve the conflict in his or her mind between the question asked and reality.
Question: "How many customers are using the platform?"
Answer: "We actually have over 100 companies."
The word "actually" isn't important to the answer. It's extra information that makes the listener curious as to why the word was added. An astute investor or customer will follow up with a request to see a customer list or to get a customer referral.
Question: "Do you use this product?"
Answer: "Actually, I have."
To the experienced listener, this answer actually (get it?) means, "No, I have never used it" or "I used it once and it didn't do what I expected or needed." An appropriate follow-up is to ask for a specific example or time that the function was used.
Perfecting your pitch requires attention to what you say and removing anything that distracts them from your primary message. As a listener, keying in on the word "actually" can clue you in to the subconscious and give you a competitive edge.


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SET_TID_ADDRESSSection: Linux Programmer's Manual (2)
Index Return to Main Contents
NAMEset_tid_address - set pointer to thread ID
_TAG_ long set_tid_address(int *tidptr);
DESCRIPTIONThe kernel keeps for each process two values called set_child_tid and clear_child_tid that are NULL by default.
set_child_tidIf a process is started using clone(2) with the CLONE_CHILD_SETTID flag, set_child_tid is set to child_tidptr, the fifth parameter of that system call.
clear_child_tidIf a process is started using clone(2) with the CLONE_CHILD_CLEARTID flag, clear_child_tid is set to child_tidptr, the fifth parameter of that system call.
The system call set_tid_address() sets the clear_child_tid value for the calling process to tidptr.
When clear_child_tid is set, and the process exits, and the process was sharing memory with other processes or threads, then 0 is written at this address, and a futex(child_tidptr, FUTEX_WAKE, 1, NULL, NULL, 0); call is done. (That is, wake a single process waiting on this futex.) Errors are ignored.
RETURN VALUEset_tid_address() always returns the PID of the calling process.
ERRORSset_tid_address() always succeeds.
VERSIONSThis call is present since Linux 2.5.48. Details as given here are valid since Linux 2.5.49.
CONFORMING TOThis system call is Linux specific.
SEE ALSOclone(2), futex(2)
- RETURN VALUE
- CONFORMING TO
- SEE ALSO


text:
From CS294-69 Image Manipulation and Computational Photography Fa11
Name: Hong Wu
Assignment: Assignment 3
Course: CS294-69, Fall 2011, UC Berkeley
Paper Implemented: GradientShop: A Gradient-Domain Optimization Framework for Image and Video Filtering. Pravin Bhat, C. Lawrence Zitnick, Michael Cohen and Brian Curless. (pdf)
Our formulation is greatly inspired by the recent work on gradient domain image filtering where direct manipulation and use of image gradients has played a central role. These methods rely on the fact that gradients are integral to the way in which we perceive images.
Base on the fact that Human Vision System (HVS) largely relies on edges and contract, the above paper focuses on easily specifying both zeroth order constraints (i.e., desired pixel values) and first order constraints (i.e., desired pixel gradients in space) in the optimization.
The paper proposes a formula to minimize the energy which contains both data cost and gradient cost.
d provides data constraint for each pixel in desired image f. g is the desired derivative in x and y direction. The image w provides the weight on d and two directions of g.
Instead of using naive weight function
the paper applies a formula based on L1-norm to reduce the influence of the noise.
Figure: Original image of dolphin.
Based on long edge detecting, the paper only enhances the magnitude of gradients along the long edges rather than along gradient magnitude. By doing this, it avoid to enhance image noise or background clutter.
Figure: Long edge enhancement of dolphin.
Pseudo image relighting
The paper add artificial lighting resource by manually specifying a lighting direction. And then, the algorithm boosts the gradients according to the angle between artificial lighting direction and the gradient direction.
Figure: Relighting of dolphin by adding artificial lighting resource at up-right corner.
The purpose of this application is to photographs into a painterly look. The method is to exaggerate salient features and abstract non-salient features. In another word, the method decrease the gradient at short and no edge and increase the gradient at long edge region.
Figure: Dolphin with painterly rendering effect.
Figure: Original image of beauty.
Figure: Long edge enhancement of beauty.
Figure: Relighting of beauty by adding artificial lighting resource at up-right corner.
Figure: Beauty with painterly rendering effect.


What are they?
While a general Location will work for most of your needs, there are times when you need an additional level of specificity about an item's location. Sub Locations give you the ability to store even more detailed location-related information.
An example of this would be a situation where you have a storage facility and want to have a more specific description of where the item is located i.e. Storage Facility: Bin 20. Where "Storage Facility" is the Location and "Bin 20" is the sub-location. This is also handy for drawers, floors, and other situations that call for more location detail.
Note: Sub-locations are available only on Organization plans.
How do I create a Sub-Location?
There are few ways to do this and here are the most common.
Creating a Sub-Location within a new Location:
Click on Locations in the left-side menu. Then click New in the top menu.
During the process of adding a new Location you can add Sub Locations by clicking the blue Add Sub-Location on the right-hand side.
Adding Sub-Locations to an existing Location
Click on Locations in the left-side menu and then select the Location to which you'd like to add a Sub-Location.
Once on that Location's page, you can click Sub-Locations in the top menu.
Then select Add/Edit Sub Locations. This will allow you to create a new Sub-Location for that Location.
How do I assign a Piece to an existing Sub-Location?
Click on Artwork on the left-side menu.
Select the artwork you want to assign to a Sub-Location.
Then click on the blue New Location Record next to Location History.
Choose a Location from the drop-down menu or click the New Location button and enter the information. Choose the Sub-Location from the drop-down menu. Click Save.
Did this answer your question?


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|Document revision date: 30 March 2001|
The following keys recall commands:
The following keys control cursor position:
The following keys control screen display:
This chapter describes how to create and manipulate files locally, and over a TCP/IP or DECnet for OpenVMS network. This chapter includes information about:
For additional information, refer to the following:
A file is a unit that the OpenVMS operating system uses to store human-readable and machine-readable data. When you create or name a file, you must specify certain information so that the system can locate and identify the file. You do not have to include all the elements of a complete file specification (see Section 4.1.1). However, you must specify enough of the file specification so that, when combined with default components, the system can locate and identify the correct file according to the RMS facility's rules for file specification parsing. Refer to the Guide to OpenVMS File Applications for more information on how RMS applies defaults to partial file specifications.
If you are working in an environment with Extended File Specifications, refer to the OpenVMS Guide to Extended File Specifications for specific information about extended file names and the expanded character set available.
To override system defaults or to perform file operations over a network, you must provide a complete file specification. A complete file specification has the following format:
The components are as follows:
|Node||A network node or host name; applicable only to systems that support TCP/IP or DECnet. Does not apply to files stored on magnetic tape. Should not be used to specify a file on the same system that the user is logged in to.|
|Device||The name of the physical device on which the file is stored or is to be written.|
|Directory||The name of the directory that is used as a prefix for the directory component (See directory component description below.) Square brackets () or angle brackets (<>) are used to delimit root names. The last character of a root component before the closing bracket must be a period (.). The root component does not apply to files stored on magnetic tape.|
|Filename||The name of the file.|
|Filetype||By convention, identification of the structure or the type of the file. Many utilities provide a default value for a file's type, according to the convention, as a convenience.|
|Version||The version number of the file. Versions are identified by a decimal number, which is incremented by 1 each time a new version of the file is created. The system automatically assigns a version number unless you specify one.|
Use the following rules to specify the elements of a file specification:
For more details, refer to the Guide to OpenVMS File Applications.
Note that these rules differ for files in an environment with Extended File Specifications. Refer to the OpenVMS Guide to Extended File Specifications for more specific information about extended file names.
With certain commands, if you omit the file type, the system applies a default value. The following table lists some of the more common default file types used by DCL commands:
|.CLD||Command description file|
|.COM||Command procedure file|
|.DIF||Output file created by the DIFFERENCES command|
|.DIS||Distribution list file for the Mail utility|
|.EDT||Startup command file for the EDT editor|
|.EXE||Executable program image file created by the linker|
|.HLB||Help text library file|
|.HLP||Input source file for help libraries|
|.JOU||Journal file created by the EDT editor|
|.LIS||Listing file created by a language compiler or assembler; default input file for the PRINT and TYPE commands|
|.LOG||Batch job output file|
|.MAI||Mail message file|
|.MEM||Output file created by DIGITAL Standard Runoff (DSR)|
|.PS||POSTSCRIPT format file|
|.REGIS||Regis format file|
|.RNO||Input source file for DIGITAL Standard Runoff (DSR)|
|.SIX||Sixel graphic file|
|.SYS||System image file|
|.TJL||Journal file created by the DECTPU and ACL editors|
|.TLB||Text library file|
|.TPU||Command file for the EVE editor|
|.TPU$JOURNAL||Journal file created by the EVE editor|
|.TXT||Input file for text libraries or Mail utility output files|
The following table lists the default file types for some high-level language source programs:
|.ADA||Input source file for the Compaq Ada compiler|
|.BAS||Input source file for the BASIC compiler|
|.B32||Input source file for the VAX BLISS-32 compiler|
|.C||Input source file for the Compaq C compiler|
|.COB||Input source file for the VAX COBOL compiler on OpenVMS VAX systems and the Compaq COBOL compiler on OpenVMS Alpha systems|
|.FOR||Input source file for Compaq Fortran (Compaq Fortran for OpenVMS VAX systems was formerly VAX Fortran)|
|.M64||Input source file for the MACRO-64 assembler for OpenVMS Alpha|
|.MAP||Memory allocation map created by the Linker utility|
|.MAR||Input source file for the VAX MACRO assembler or the MACRO-32 Compiler for OpenVMS Alpha|
|.MLB||Macro library for the MACRO assembler|
|.MSG||Source file that specifies the text of messages|
|.OBJ||Object file created by a language compiler or assembler|
|.OLB||Object module library|
|.OPT||Options file for input to the LINK command|
|.PAS||Input source file for the Pascal compiler|
|.PLI||Input source file for the PL/I compiler|
|.STB||Symbol table file created by the Linker utility|
|.UPD||Update file of changes for a VAX MACRO source program; also input to the SUMSLP utility|
In addition to a file name and file type, every file has a version number. Version numbers are decimal numbers from 1 to 32,767 that differentiate versions of a file. When you create a file, the system assigns it the version number 1.
You can have several versions of the same file. Unless you specify a version number, the system uses the highest existing version number of that file. If you specify the version number 0, the system uses the highest existing version. When you modify a file with a command, application, or text editor (such as EVE) that creates a new version of the file, the file name remains the same but the version number is incremented by one.
Precede version numbers with a semicolon or a period. When the system displays file specifications, it displays a semicolon in front of the file version number.
You can refer to versions of a file in a relative manner by specifying a zero or a negative version number. Specifying zero locates the latest (highest numbered) version of the file. Specifying -1 locates the next-most-recent version, -2 the version before that, and so on. To locate the earliest (lowest numbered) version of a file, specify -0 as the version number. Note that you cannot create files with a version number higher than 32767. If you attempt to create a new file with a version number higher than 32767, you will receive an error message.
The /VERSION_LIMIT qualifier for the CREATE/DIRECTORY, SET DIRECTORY,
and SET FILE commands lets you control the number of versions of a
file. If you exceed the version limit, the system automatically purges
the lowest version file in excess of the limit. For example, if the
version limit is 5 and you create the sixth version of a file
(ACCOUNTS.DAT;6), the system deletes the first version of the file
(ACCOUNTS.DAT;1). To view the version limit on a file, enter the
DIRECTORY/FULL command. The version limit is listed in the
4.1.6 Network Node Names
A node is an individual computing system that is part of a computer network. If your system is part of a network, the node that you access when you log in is your local node. Other nodes in the network are remote nodes. Use a node name when you want to specify a file on a remote node.
A node specification has the following format:
Observe the following rules when entering a node name as part of a file specification:
On OpenVMS systems, you can specify node full names. However, you must have DECnet--Plus software installed for full node names to be recognized.
Valid full node names can contain up to 255 characters and can include any characters except the following:
If a full node name is enclosed in quotation marks (" "), it can contain any characters except unmatched quotation marks. Note that if there are quotation marks within the node name, the quotation marks must be doubled and the entire string, including the quotation marks, must also be enclosed in quotation marks.
Although the OpenVMS software enforces few rules on the syntax of node names, the actual set of valid node names is constrained by the DECnet software running on your system. For further information on full names, refer to the DECnet--Plus documentation. The syntax rules, including valid character codes, are described in detail in the DECnet--Plus DECdns Management Guide.
In the following example, the entire string is in quotation marks because there are quotation marks in the node name:
Other examples of valid full node names are:
With TCP/IP, unless otherwise stated, whenever you specify a host on a command line, you can use its host name, a fully qualified domain name, or its IP address. The relative name of a host is a simple name


ACG Investigators Identify Factors Linked to Colectomies
November 6, 2019
Kenny Walter
Miguel Regueiro, MD and George Khoudari, MD, both of the Cleveland Clinic, discuss predictors of colectomies for IBD-patients.
Why do some patients with inflammatory bowel disease (IBD) have to undergo colectomies and what can be done to better forecast who will require the surgery?
During the American College of Gastroenterology's Annual Scientific Meeting (ACG 2019), Miguel Regueiro, MD, chair of the Department of Gastroenterology, Hepatology, and Nutrition at the Cleveland Clinic, and George Khoudari, MD, a physician with the Cleveland Clinic, discuss in an interview with MD Magazine® the colectomy predictor population-based cohort study and what it will be used for in the future.
MD Magazine: What is the importance of the study?
Regueiro: The importance of the study and the reason that we entertained this study at all was that there are still patients with ulcerative colitis and Crohn's disease who need surgery and specifically need a colectomy.
One of the things we were interested in looking at was what are potentially some of these predictors of colectomy in these patients. Maybe if we could identify those predictors we could better determine who may need surgery or who may respond to medications.
MD Magazine: What was the methodology used in the study?
Khoudari: So we did this study using the inpatient database and we looked at patients with IBD. We also looked at the patients who had colectomy.
We had a total of 3.5 million patients who had IBD, 71,000 of these patients had colectomies and we looked at the predictors for colectomy in these patients.
MD Magazine: What were the results of colectomy predictor study?
Khoudari: So IBD patients who are young, male, African American have a higher risk of colectomy. Also, IBD patients with infections like Clostridium difficile, cytomegalovirus also are at high risk of colectomies.
MD Magazine: How will the study be used in the future to improve patient outcomes?
Khoudari: So in this database we can look for associations, but we can look for mechanism for why this has happened.


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Whether you're researching keywords, reviewing lead sources, or analyzing customer attributes from a CRM export, Google Sheets' COUNTIF and COUNTIFS formulas can help.
These two spreadsheet formulas will only count a cell (from a range of cells) if specific criteria are met.
Recently, a multichannel retailer wanted to analyze five years' worth of lead and conversion data from its customer relationship management software. Leads might come from the retailer's website, its various digital marketing efforts, offline advertising, or folks just walking into a store.
…a multichannel retailer wanted to analyze five years' worth of lead and conversion data…
The company sells relatively expensive products that range from $10,000 to $50,000 each. Thus, it may take a few contacts to close a sale. Understanding which sources produce leads could help the retailer understand how to get more customers.
Unfortunately, the company's CRM did not provide the required report. So a couple of folks from the retailer's marketing department exported the data in comma-separated values format. This CSV file was uploaded to a Google Sheet, and thanks to COUNTIF and COUNTIFS, it was fairly easy to identify which lead sources produced the most sales.
To demonstrate how to apply COUNTIF and COUNTIFS formulas, I'll use sample data.
The data has four columns: an order number, the U.S. state from which the order was placed, the lead source, and the sale amount. For the examples, I'll focus on just two of these columns: the state and the lead source. The name of the sheet is "Lead Data." Notice that I included this name the range of cells.
I will create a second sheet to analyze lead sources by U.S. state. This sheet will have a column to list the states, the total count for each state, and the count and percentage of the total for each lead source.
I will use the COUNTIF formula to get the total number of orders originating from each state. The formula accepts two parameters, the range and the criterion.
The range is any set of cells in the current sheet or another sheet. Our range will come from the "Lead Data" sheet and not the current one.
Typing "=COUNTIF" into the formula bar in Google Sheets will auto-generate formula options from a list. Select "=COUNTIF" and navigate to the range and then drag to select it.
When a cell contains text, the criterion is quoted. For our example, I first wanted to get a count of all of the sales to California — designated as "CA" in the cells of the state column. This is what the COUNTIF formula looked like:
=COUNTIF('Lead Data'!B2:B25, "CA")
The section describing the sheet and range uses 'Lead Data'!B2:B25 as the range and the state ("CA") for the criterion. If the range had been in the same or current sheet, it would not have included the sheet name.
I can use this same approach to get the count for each state on the list.
The formula is similar to COUNTIF. In this case, we are counting only rows that have "CA" in the state column.
=COUNTIFS('Lead Data'!B2:B25, "CA")
To this, we add a comma, followed by a second range and a second criterion — Facebook in this example.
=COUNTIFS('Lead Data'!B2:B25, "CA", 'Lead Data'!C2:C25, "Facebook")
Changing the criterion for the state will give us a count of the leads from Facebook that converted consumers from each state. For our example, I also wanted to know the percentage of total leads these represented. So I can add a slash and a reference to the total leads for a given state.
=COUNTIFS(('Lead Data'!B2:B25, "CA", 'Lead Data'!C2:C25, "Facebook")/B3)
You can also include operators in the criterion value for either COUNTIF or COUNTIFS. Place these inside the quotation marks surrounding the criterion value.
Here are some examples.
- "<>CA" — Not equal "CA" where "<>" means not equal.
- ">10" — Greater than 10.
- "<10" — Less than 10.
- ">=10" — Greater than or equal to 10.
- "<=10" — Less than or equal to 10.
Finally, there are also two available wildcard characters for criterion values.
-? — Matches any single character.
- * — Matches zero or more contiguous characters.
To match an actual? or *, put a tilde (~) in front of it. For example, "~?" would match a question mark.


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Progress indicators are a powerful tool to help your customers complete their form-filling journey. They inform, reassure and encourage users when completing a longer online form spread over multiple steps.
Above we can see Apple's checkout. Ever the contrarians, Apple does not have any sort of progress bar in the checkout. How many steps are there? Do I have to pay in full, or will I be able to choose to finance my purchase? Can I amend previous information by jumping back to a previous step? Am I almost there? No idea.
Progress bars play an important role in reducing the anxiety many users feel when faced with a long form: how long is this going to take me? Will I manage to finish it before I need to go out? Is it just going to be a waste of my precious time?
There are several ways of showing progress within a form, including progress bars and inline validation, and they both have valuable benefits:
Progress bars can appear either inside or outside the form. There are three main types:
Percentage bar – this displays how far a user has progressed through the form in percentage terms. Starting fast and ending at a slower pace will reduce drop-off rates as satisfaction levels spike quickly. The perception is that most of the work has already been done.
Steps left bar – this option indicates how many steps have been completed and how many are left. Again, this is a numerically-pleasing method of showing progress which is often designed to look like a path to completion.\
Checklist bar – similar to the steps left approach but the fields don't need to be completed in a specific order. This gives the customer the freedom to move through the form in their preferred way, for example completing the most complicated fields first to get them out of the way.
All of these options provide feedback on the users' actions. What they're inputting is being taken on board, the interface reassures them that the system is working: the computer says yes.
Informative and honest guidance like this reduces uncertainty and creates the impression of speed, progression and achievement. It humanises the process, harnessing the emotional rather than the technical journey a user is on and making it a positive experience.
Taige Zhang, senior product manager at online grocery delivery service Shipt, states in his blog The Power of The Progress Bar: "If I had to pick out the most effective tool for onboarding a user, it would be the progress bar."
But why are they so effective?
It's all down to psychology. Specifically, gamification.
Incorporating game design elements in non-game contexts – in this case, points that take the form of the stages in a progress indicator – can dramatically improve user engagement.
Described by Peep Laja, Chief Conversion Officer at conversion marketing agency Markitekt, as a "path to mastery", gamification encourages users to engage in desired behaviours via reward-based methods.
The technique taps into several psychological phenomena:
Incomplete tasks – and an incomplete progress bar – can stay stuck in your customer's memory. Focusing on it, and only being able to imagine completion, can lead to tension: when can I finish it? Will the information I've already inputted still be there? Can I remember the password I used?
Doing something to resolve this tension – returning to the form to finish it – is a form of negative reinforcement. You've silenced the nagging voice and can enjoy the bonus of positive reinforcement: form is filled in, tick is made on to-do list.
We inherently feel good when we achieve something and this is backed up by neuroscience. Zhang quotes an article written by Dr Hugo Liu from MIT and hunch.com in which he says: "It turns out that when you finish a complex task, your brain releases massive quantities of endorphins."
The reward for this "need to complete" is powerful: you know that when you complete a project, your spirits will be lifted. This knowledge spurs you on to keep going.
Harness this effect within your forms and you're much more likely to be successfully cheering your customers over the finish line.
There's also another important reason why progress bars are a good idea - they make for a more open, transparent and honest user interface. They allow users to judge the effort required to complete the journey on your site and decide if it is worth their time.
If a progress bar decreases your conversion rate, it's likely that your form was too long to begin with. By removing it, you're essentially hiding the fact that your form is so long you don't think users will complete it and relying on them sticking with it after spending time on the first few steps. Essentially, you're exploiting the sunk cost of users.
Each of the different steps of your form have probably been crafted to ask for a different type of information at each step (rather than including a random number of unordered questions on each).
You may there want to consider some combination of numbered steps and section titles for each.
Here are forms with only section titles:
Here's one with only numbers:
And here a selection with a combination:
Which should you choose?
Well, if you're looking beyond the benefits of a progress bar to incentivise your users to complete, you'll recall that the progress bar adds clarity and openness to your UX. It goes some way to setting expectations about the journey ahead and prepares users for the information they may need to enter.
Having numbers only therefore does add some clarity but does not prepare users for what kind of information they are going to be asked for at each stage - what exactly is Step 4? Order confirmation, bank details, my life history? Similarly, having section titles only sets expectations but doesn't indicate clearly how many different stages there are going to be.
For example, this form has one or two questions on a series of mini-steps, across 5 sections:
A user only realises that there are actually lots of small steps after starting, and the larger section titles are actually not an indication of how many steps still lie ahead.
So if you're aiming for maximum clarity for users, include both Section Titles and either Numbers or a Percentage indicator. This prepares users both for the kind of information they're going to be asked for, and gives an indication of the number of steps completed and ahead of them.
Another advantage of progress bars is that it may allow a user to skip back to a previous step to review or amend information, like in the below:
If your journey requires a lot of complex, detailed information and there's an important product or service at stake, users will be tempted to review, go back, amend, and change information on previous steps before attempting a submit.
A progress bar allows them to easily access previously entered but no longer visible information. If you do not allow for this skipping about, a user will either press a back button in your form multiple times (unnecessary friction) or worse use the Back button in their browser. Sometimes this will cause the form to be wiped, setting the user back to the start.
If you suspect your users do want to review or amend information, you should support this, rather than force them in one direction and risk abandonment.
Zuko is the most powerful form analytics platform available on the market. Find out how to improve your form and checkout conversion by taking a product tour.PRODUCT TOUR


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- Log in to the control panel and open Website Builder.
- Go to the Components tab and drag the Image Slider component in your work space.
- Select the images you want to insert, or upload them from your computer or an external URL.
- Adjust the size and placement of the slider component to your liking;
- Type in the exact dimensions in the green box visible when the component is selected.
- Drag the resize handles to the size you want.
- Adjust the Properties of the image.
- Click Save in the top left corner and Publish to make the slider visible on your site.
Properties of the image slider component
Set how your image slider should be displayed on your website in the Properties tab.
- Images - You can see how many images are included in the slideshow. Click Sort & Edit to change the order of the images or edit them. Click the image icon to add or remove images.
- Forward/back - Select whether the navigation arrows should always be visible, only when you mouse over or never.
- Indicator - The indicator shows dots to indicate the amount of images in a slider and which is the active image in the list. Select whether the indicator should always be visible, only when you mouse over or never.
- Transition - Select if you want a fade or slide transition between images.
- Crop images - Check this box if you want your images to be cropped to the same size. That way each image will completely fill out the component.
- On click - Select what should happen if a visitor clicks the image. You can select to do nothing, to show large images or to open a link. To add the link, click the link icon in the top right corner for each image in the component.
- Captions - Check this box if you want to add captions to the images in the slider. You can select alignment and placement. To add the text, double click each image in the component.


How To Find Bees In Minecraft?
Where do you find bees in Minecraft?
Why can't I find bees in Minecraft?
You can find bees in Minecraft in flower forests, plains and sunflower plain biomes following update 1.15. Any tree in the above biomes can harvest a bee nest, but the flower forest is your greatest bet for finding them quickly.
How rare is it to find a beehive in Minecraft?
Bee nests now have a 0.2% chance to spawn in forest, wooded hills, birch forest, tall birch forest, birch forest hills, and tall birch hills biomes. Bee nests now appear yellow on maps.
How do I get bees in my beehive Minecraft?
Can u tame bees in Minecraft?
In order to tame minecraft bees you need flowers, it is really easy. Minecraft 1.15, the first release of Buzzy Bees, is a major update to Java Edition released on December 10, 2019.It added bees and bee-related items, such as beehives, honey bottles and honeycombs.
How do you farm bees in Minecraft?
Bees can be lured using any type of flower (including 2-block flowers and wither roses), and can also be moved using leads. (The bees follow the flowers because they want to eat them. If you feed the bees the flowers, they will enter love mode and breed, producing a baby bee.)
See also: Often asked: Best Minecraft 1.12.2 Mods?
Do bees spawn in beehives Minecraft?
Bees are a neutral mob — they'll only attack when they've been attacked — that spawn naturally in bee nests attached to oak or birch trees. They're a fan of flowers so they have a higher chance of spawning in places that have a lot of flowers and the specific trees that they enjoy.
How do you summon bees in Minecraft?
You can summon a bee whenever you want using a cheat (game command) in Minecraft. This is done using the /summon command.
How long do bees stay mad Minecraft?
In Peaceful mode there will be no effect. Once successful, they will lose their stinger and will become passive, but will instantly die after 20 seconds. Placing a campfire or having a fire under a hive will stop hostility. They will go into bee nests and hives.
How do you get Honeycomb?
Honeycomb can be harvested from bee nests and hives (artificial versions of nests you can craft) with shears; you'll get between one and three bits of honeycomb that way. However, harvesting from bee nests will make its buzzy inhabitants hostile.
Why is my beehive empty Minecraft?
The bees could be getting polin. Leave it until night, if bees are still alive or around they'll come back.
How do you get honey from a beehive in Minecraft without getting stung?
To collect honey without getting stung by bees is easy. You'll need to place a campfire right under the bee's nest. Place it right under it and you'll never see their red creepy eyes again.
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This exhibit formed part of a Darwin display in South Kensington Museum during late Victorian times.
The Natural History Museum,London
Black Scandaroon from a German Pigeon show
Mick Bassett Germany
Scandaroon chick June 2010
approx 3 weeks of age
The Scandaroon is an ancient breed of fancy pigeon. It has a most distinct beak which is long and curves downwards and a striking red eye cere. Darwin called these birds Scandaroon Runts and they caught his attention.
The breed in Victorian England was only ever kept by a few fanciers, as is the case today. It is thought that the name came from the port of Scandaroon in the Levant however the breed origin is most likely to be ancient Persia. Scandaroon is the Turkish word for Alexander and it is possible that this being an old breed it was used as a message carrier by Alexander the Great in his conquests. This part of Asia is strongly associated with early pigeon breeds.
The Scandaroon used by Darwin was the Bagdotten type imported through France almost certainly coming from stock developed in Nurnburg, Germany. This is a larger bird than the type known in England and this was apparent to me when I visited the Dutch National show in January 2011.
The European Scandaroons are larger in size and weight, the beak is much stronger and longer but interestingly not as curved as its English counterpart. The feet are larger which confirms Darwin's own findings of large beak, large feet. It would seem the English fanciers have always preferred the smaller birds which have more of a curve to the beak, even 100 years ago an English fancier writing in a journal states "the German birds were too large and ugly." Darwin was interested in the extremes of types and the German type bird suited him well.
The French have developed their own type which is taller, more upright in stance and slimmer naming it the French Baghdad. So, in three countries fairly close to each other we see how Man has changed the direction a breed can be altered.
The French Baghdad has been used in crosses with several other breeds to improve and alter them such as the English Magpie which was a shorter legged, flying type pigeon in Darwin's time. I have handled one of Darwin's own Magpie specimens in the Natural History Museum at Tring which bears this out. Now, the English Magpie is both taller, more elegant and purely a show pigeon. Also in the collection at Tring is the skull of the Scandaroon donated by Darwin and it has been noted by Hein van Grouw, a Curator of Birds at the museum, that the drawing of such in Darwin's Variation and Domestication has the lower mandible missing. This intrigued Hein who checked the actual skull in the collection and found this was also missing its lower mandible. Since this discovery Katrina van Grouw has drawn a complete skull including the lower mandible. see picture on this page
Despite what seems an ungainly beak the Scandaroon is a most attentive and capable parent. Although at first glance the breed is somewhat ugly, they are calm, quiet, intelligent and interesting pigeons to keep and study. Darwin was disappointed when he lost a hen of his pair to illness.
Colours include white, black, blue, red and yellow. In England the birds shown are generally the pied version having a white head, coloured patch under the beak, mainly white wings and a coloured tail.
for Scandaroon pigeons
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Garnish, an embellishment added to a food to enhance its appearance or taste. Simple garnishes such as chopped herbs, decoratively cut lemons, parsley and watercress sprigs, browned breadcrumbs, sieved hardcooked eggs, and broiled tomatoes are appropriate to a wide variety of foods; their purpose is to provide contrast in colour, texture, and taste, and to give a finished appearance to the dish.
In the classic cuisine of France, garnishes comprised any accompaniment to a principal dish—vegetables and starch dishes fell under this definition. Further, basic dishes could be varied by the selection of one of a codified array of garnishes. Under this system a chicken, for example, could be served à la archiduc, with a sauce of paprika and cream; à la forestière, with morels and potatoes, à la bouquetière, with an array of individually cooked, decoratively cut vegetables, and so on into hundreds of formulations.


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This is a paired comparison questionenter image description here:
The answer is: enter image description here
However, this is my thought of using a t test on difference of population means
enter image description here
$$t=\frac{583.125 - 415 - 0}{\sqrt{\frac{_PHONE_^2}{8}+\frac{_PHONE_^2}{8}}}$$
$t= 1.2829$
enter image description here
critital value $t_{0.05}(df=14)$= 1.76131
$1.2829 < 1.76131$
therefore no difference between the mean daily sales from the two stores. Why am I getting a different conclusion? Is it reasonable to think about it this way?
share|cite|improve this question
I suppose $s_1^2$ is the sample variance of $\bar{x}_1$ and $s_2^2$ is the sample variance of $\bar{x}_2$. In that case, the sample variance of $\bar{x}_{1}-\bar{x}_{2}$ is not equal to the sum of variance unless covariance is equal to zero. Hence, the denominator of your statistics does not seem to be correct. Moreover, the degrees of freedom are 7 because you only lose 1 observation when computing the var of the difference of the means. – Cristian Oct 3 '12 at 19:03
Sorry I didn't look at the formula used for the two sample t test. I assumed it was correct. Maybe that is another mistake but the key point is that it is the sample variance of the paired difference that needs to be used. If you like my answer so much why not give me an upvote. It seems to be awfully difficult on this site to get upvotes. – Michael Chernick Oct 4 '12 at 1:40
_USER_ yes, thank you for answering, but it looks like you have discussed the topic in CV, but Im wondering what is CV... – user133466 Oct 4 '12 at 15:35
_USER_ why do you think using the formula for 2 sample t test is incorrect in this scenario? I think we can use it because has been used to determine difference of population means. my thoughts are, if anything, this and the paired t test should come to the same conclusion... – user133466 Oct 4 '12 at 17:59
_USER_ If you have a big seasonal effect the variance of the two sample t test can be much higher than the paired test and that will hold even though one has more dfs than the other. Also you are using the unequal variance assumption for the two sample test. So it does not have a t distribution under the null hypothesis. It becomes the Behrens-Fisher problem and has Welch's distribution which is approximated by a t test. I thought Cristian was implying that you were using the wrong formula for the test because there was an algebraic eror in the formula you used. – Michael Chernick Oct 4 '12 at 18:55
1 Answer 1
up vote 1 down vote accepted
You are using the formula for the unpaired two sample t test. The paired t test is like a one-sample test of the null hypothesis that the paired difference is 0 vs alternative that it is different from 0. The test statistic and the degrees of freedom are different. It is a more appropriate and more powerful test when the pairs are positively correlated. I have discussed this in posts on CV.
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thanks for answering michael, what exactly is a CV? – user133466 Oct 4 '12 at 0:10
Yes! an answer!!! Michael you're AWSOME!!!! – user133466 Oct 4 '12 at 0:28
CV is short for Cross Validation. It is an SE site where statisticians, machine learning/data mining expert – Michael Chernick Oct 4 '12 at 17:41
Your Answer


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Jean Minch, Puyallup, Washington
Through years of struggling to keep our rhododendrons and azaleas alive during the hot summer months with just about every kind of watering system, including impact sprinklers, soakers, drip systems and even the bucket brigade, we found we were drowning some while others were drying up and dying. Finally after several years of persuasion by our son-in-law, an apple farmer in Chelan, Washington, we decided to try the system he uses in his orchards. During the hottest week of the summer of '85, with our beloved plants dying daily, we installed the new system and now wonder why we didn't listen to Fritz years ago.
This is a system of micro-sprinklers that puts out a fine mist, duplicating the tropical moistness rhododendrons like so well. It gives off a soft caressing mist that surrounds even the most delicate flower without harm. A slight breeze swirls the mist in and around the leaves and plant and refreshes the garden like a soft summer rain. The water then settles to the ground keeping the moistness on the shallow roots. Rhododendrons do not wish to stand in water or in soil that is soggy, although they enjoy a cool, moist soil. Because their roots are shallow, heavy watering is a waste and takes the nutrients on down past the root system.
| Low volume sprinkler system at work.
Photo by Jean Minch
Since the use of these micro-sprinklers is relatively new in orchards and vineyards and even newer in rhododendron culture we have had to rely on the experience of orchardists. Micro-sprinklers have reduced application rates significantly and are able to spread the available water over more acreage than impact sprinklers. An impact sprinkler primarily throws a stream of water, a micro-sprinkler uses a spinning head which throws a circular pattern of small droplets. Each droplet is a sphere, the surface of which is exposed to the air. With more droplets of smaller size the actual water-to-air surface is increased significantly. Increased water-to-air surface increases the absolute amount of evaporation.
This brings up another plus, the use of micro-sprinklers for frost control. They are efficient at raising air humidity levels, creating a humidified "micro-climate" and can provide frost protection at lower application rates. During the early spring when the delicate buds and flowers are starting to open they can be protected by a steady flow of droplets that completely and gently encircle the bud. The buds have to be protected from thawing until the temperature raises to 34°.
The volume of water used by 40 to 50 micro-sprinklers is similar to that of one impact sprinkler. An impact sprinkler waters a large circumference with the outer ring getting most of the spray and some of the inner circle getting little or no water. During blooming season the harsh heavy spray does little to enhance the beauty of the flower. The system of micro-sprinklers reduces the amount of water used, distributes it evenly and is gentle with both foliage and flowers.
| Low volume sprinkler head.
Photo by Jean Minch
With all the benefits of systemized and economical watering, freeze control, etc. it would seem almost too much to expect the installation to be comparatively simple and economical. Approximately 40 micro-sprinklers equals the cost of one standard impact sprinkler. Our particular garden covers approximately three acres. It is on a hill that is very steep in places, has many ridges, ledges, corners and strips along buildings and roads but all our plants are covered with equal care. Two of us basically installed all three acres, plus two lath houses in approximately one week. The micro-sprinklers have features that permit a variety of applications; for example: peripheral or sectional spray irrigation, sprinkler irrigation, misting, change of diameter coverage or change of droplet size.
A final feature that we added to our system was some good quality, battery operated timers. We use battery operated timers to eliminate the expense of extensive electrical work and to allow us to have them in remote areas where electricity is not available. Routine watering for 10 minutes twice a day in the early morning, about 5 AM, and late afternoon, after 6 PM, is most effective for our garden. However, we frequently turn them on just for the joy of watching the beautiful effect.
For more information on the Minch's garden see the article "The Indomitable Fred Minch" by Linda Draper, ARS Journal, Vol. 40:1, Winter 1986.
Jean Minch, an avid photographer, shares her husband Fred's enthusiasm for growing rhododendrons.


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Arne Duncan, Secretary of the U.S. Department of Education: National Prevention Strategy Series
The National Prevention and Health Promotion Strategy offers a comprehensive plan to increase the number of Americans who are healthy at every stage of life. A cornerstone of the Strategy is that it recognizes that good health comes not just from quality medical care, but also from the conditions we face where we live, learn, work and play—such as healthy homes, clean water and air and safe worksites. The strategy was developed by the National Prevention Council, which is composed of 17 federal agencies including the Department of Education, the Department of Housing and Urban Development and others.
As the Strategy is rolled out, NewPublicHealth will be speaking with Cabinet Secretaries, Agency directors and their designees to the Prevention Council about their prevention initiatives. Follow the series here.
We spoke with Arne Duncan, Secretary of the U.S. Department of Education, about the connection between health and education. Listen to the short podcast, and read the full interview below.
NewPublicHealth.org: The Department of Education is a member of the National Prevention Council. Why is health a priority for the Department?
Secretary Duncan: Very simply, if children aren't healthy they can't fulfill their academic and social potential. I always talk about the foundation of building blocks for great education, which includes good physical and emotional health. If children can't see the blackboard they can't do well. If children are hungry they can't do well. If children are obese they are not going to do as well as they should. So we have to collectively make sure that children are physically and emotionally healthy so they can think about AP Chemistry and Biology and Physics and the rest of their learning.
NPH: What are the Department of Education's key target areas and specific initiatives in implementing the National Prevention Strategy?
Secretary Duncan: We want to do everything we can to make sure that the children's good health is the norm rather than the exception. When you have one out of three young children being overweight or obese, you're putting them at risk for serious illnesses. That's a real challenge. So we're trying to do everything we can. For the first time this year we've introduced a great program called U.S. Department of Education Green Ribbon Schools that highlights schools that have done an amazing job of reducing environmental impact and costs, and improving health in integrating sustainability into the curriculum. We want to be a great partner and we think if we can teach children these skills when they are young that these habits will stay with them while they are in school but also for their lifetime, and that's really what is so important to me.
NPH: How might the Department of Education work with partners to help increase physical activity at school?
Secretary Duncan: I have talked about this being a movement whose time has come and no one can do this by themselves. The private sector can't do it by themselves. The public sector can't do it by themselves. But when we're leveraging each other's resources and partnering in non-traditional ways, really creative ways, then I think we create opportunities to change children's lives forever. I worry particularly for disadvantaged communities whether that's inner city urban or rural remote. We want to increase physical activity to give children a chance to play, to have recess and there are great, great partners out there and we are all starting to work together. There was a national conference here not too long ago—just the energy in the room, the sense of shared commitment, it was just really exciting to be a part of that.
My question is always one of scale. How can we take these pockets of excellence, islands of excellence, and make them systems of excellence? How do we turn that resource into action? How do we change behavior and create many more great opportunities for young people, again particularly in historically disadvantaged communities?
NPH: What do you think is the connection between getting kids active in schools and their academic achievement?
Secretary Duncan: There's a tremendous amount of academic research that talks about how important it is for children to be physically active, that they lead healthier lives, that they have better levels of attendance, they are better able to concentrate in class. But I'll also talk from personal experience. If I didn't have a chance to run around a little bit I could be pretty tough in class. But if I had the chance to get out and run around and burn off a little steam, I could come to class and concentrate.
NPH: Mr. Secretary, how do you think schools can gain traction on creating healthier school environments for children?
Secretary Duncan: We have a couple of different grant programs. We have the Carol M. White Physical Education Program and we fund about 80 million dollars a year there, so that's an opportunity. And the 78 initial winners of the U.S. Green Ribbon Schools awards program are just extraordinary examples of what schools are doing in a creative way. So whether it's applying for resources, whether it's looking at the examples of the Green Ribbon Schools and emulating some of their best practices, I think one of the important roles we at the Department can play is to share what's working. We can be the clearing house for innovative practices at the local level and what folks are doing in their buildings, what they're doing outside, what they're doing in their communities for our children such as walking to school, and biking to school and not just riding the bus every single day. We want to be a great partner and have folks hold us accountable for stepping up and providing great, great resources and ideas and sharing what's working with folks across the country. If we can have our children enter school every single day healthy and alert and physically active then I think we have a chance to do great things academically. If we don't do those things, I really do think we put a limit. We put a ceiling on how well our students are going to do in the classroom and they deserve better than that. They need us above all else to be the leaders and to create opportunities so they can again fulfill their tremendous academic and social potential.


franklin gull
Aspen parkland
Aspen parkland refers to a transitional biome between prairie and boreal forest stretching from northeastern British Columbia through central and northwestern Alberta, central Saskatchewan to central and southern Manitoba. Aspen parkland consists of groves of aspen poplars and spruce interspersed with areas of prairie grasslands. This ecoregion is also intersected by large stream and river valleys lined with aspen-spruce forests and dense shrubbery. This is a zone of constant competition and tension. Within the parklands, prairie and woodlands struggle to overtake each other.
This article focuses on this biome in North America. Similar biomes also exist in Russia north of the steppes and in northern Europe.
The aspen parkland biome runs in a thin band no wider than 500 km through the Prairie Provinces, although it gets broader to the west, especially in Alberta. The cities of Edmonton and Saskatoon are the largest cities completely in this biome. Winnipeg is bordered by tallgrass prairie to the west and south. Calgary is bordered by prairie to the east and the Foothills Parkland to the west.
In Alberta, there are three main sections of aspen parkland: Central, Peace River and Foothills. These sections are distinguished by their geographical location. The Central Parkland is the largest section and is part of main band of aspen parkland which extends into Saskatchewan and Manitoba. It is bordered by prairie to the south and the boreal forest to the north. The Peace River Parkland is located in the Peace River region of the province and is completely surrounded by boreal forest, cut off from the Central Parkland. It also extends into northeastern British Columbia.
The climate is continental with long cold winters and short summers which tend to be cool to warm. Seasonal temperature extremes are common, and are greatest in Saskatchewan and Manitoba. Alberta's aspen parkland is fairly moderate in seasonal extremes by comparison, however, winters can still be long and harsh. Precipitation is generally lower than in the boreal forest, but is still higher than in the prairies. Hence, groves of forests and lakes are able to thrive where they cannot do so in the prairies.
The Peace River Parkland is generally cooler than the Central Parkland, but still supports extensive farmland. The Foothills Parkland is located to the west of the grasslands in the southern section of the province and just east of the Canadian Rockies. The Foothills Parkland can get very windy. Chinooks are also common there during the winter.
Four significantly different habitats are common in the aspen parklands: The fescue prairie, the woodlands, the ravines and the wetlands and lakes. A rarer habitat type, tallgrass aspen parkland, occurs only in the extreme southeastern corner of the aspen parklands biome (southeastern Manitoba/northwestern Minnesota). The fescue prairie is a meadowland rich in vegetation variety which forms the cover for the development of the richer soils that underlie the parklands. The close association with woodlands and wetlands makes this a choice location for many plants and a preferred range or home site for a wide diversity of wildlife. The richer soil and increased precipitation favours the natural growth of fescue grass. However, varying conditions such as moisture level and grazing pressures allow for the invasion of secondary plant species.
There are numerous grasses and sedges in the fescue prairie. Gravelly and rocky terrain is a good location for parry oat grass. Dry areas favour June, porcupine and spear grass. Wet areas are often covered with slender wheat grass and timber oat grass. Prairie rose and snowberry are common shrubs found in these grasslands.
The forested, or woodlands area is dominated by the trembling aspens and/or spruce, although other species of trees do occur. Pines, mostly jack pine and lodgepole pine will often grow in areas that have sandy soil conditions. Other native species may include box elder, tamarack and willow. The proportion of forests to grasslands has increased somewhat over the prairie in areas not affected by agriculture in the last 100 years. This increase is partly due to the reduction of prairie fires which used to destroy the new saplings on the fringes of the aspen groves. Also, it was a common practice for farmers to plant stands of trees as windbreaks.
Aspen woodlands support an extensive understory consisting of mid-sized and small shrubs, some herbs and ground cover. Spruce-dominated woodlands usually do not support a dense understory due to more acidic and nutrient-poor soils and a denser canopy, which reduces sunlight reaching the forest floor below. However, in areas where a mixture of aspen and spruce occur, a fairly dense understory can still thrive. In fact, the mixed wood understory, as it is called, supports the greatest diversity of forest wildlife in the aspen parkland.
Large shrubs such as red-osier dogwood, beaked willow, saskatoon, chokecherry and pincherry, along with the smaller shrubs including prickly rose, snowberry, beaked hazelnut and low bush cranberry, form a dense entangled understory. Dense shrubbery is a typical feature in aspen-dominated forests. Common herbs found in the woodlands include: Lindley's aster (Aster ciliolatus), northern bedstraw (Galium boreale), pea vine, Western Canada violet (Viola canadensis), dewberry and bunchberry. Mosses appear at the base of trees and on the ground.
Wetlands are very common in this biome, including lakes, shallow open water, marshes, and grassy wetlands. Glacial erosion has contributed to such features by creating depressions in which standing water can collect. In the larger depressions, permanent lakes or ponds of water remain. Many of the lakes have a saline character, thus most shore vegetation has a high tolerance of salty soils. These lakes are known as alkali lakes. Wet meadows are flooded in the spring and dry by fall. They contain rushes, sedges and grasses and provide excellent opportunities to study the similarities and differences of these forms of vegetation.
Rivers and streams erode valleys throughout the parkland ecoregion. Steep hills and ravines result in a unique topography. Southwest slopes with increased exposure to the sun are dry and often more grass covered while the shaded north and east exposures retain more moisture and tend to have greater forest cover. Some forms of vegetation unique to the ravines include: poplar, spruce, birch, willow, and river alder.
Wildflowers are an important component of the grassland association of the parkland. Look for common yarrow, cut-leaf anemone, rock cress, creeping white prairie aster, milk vetch, late yellow loco weed, goldenrod, prairie rose, prairie crocus, and tiger lily.
The aspen understory
There are three main factors which influence the understory vegetation in the aspen stands of the mixed wood forest.
1. Good sun exposure encourages a dense vegetation growth below the canopy. This is of particular importance in the early spring before the trees are in leaf.
2. Warm soil and air temperature at the base level result in rapid melting process in spring which favours the growth of shrubs.
3. A large percentage of precipitation passes through the canopy. This provides a protective snow cover in winter and in warm seasons precipitation percolates through the leaf cover to nourish plants which require surface soil moisture.
The result of the above factors is an extensive understory of vegetation in the aspen forest. Common shrubs and herbs are: saskatoon, red-osier dogwood, raspberry, wild rose, currants and bracted honeysuckle, wild sarsaparilla, hairy lungwort, asters, and peavine. Twinflower, strawberries, bunchberries, horsetails and wintergreen form an attractive grown cover.
The mineral soil is covered by a decaying cover of organic matter. Numerous consumers and decomposers create humus materials. Burrowing animals mix the new fertile materials with the soil to form a rich rooting compound.
The spruce forest understory
Factors which influence the understory vegetation of spruce stands in the boreal forest association include:
1. Year round reduced sun exposure below the canopy restricts the forest undergrowth to shade tolerant species.
2. A large percentage of the precipitation is trapped in the upper tree boughs of the spruce forest and is released through evaporation. The ground cover of feather moss quickly absorbs most of the moisture which does penetrate the canopy. These factors combine to cause drier conditions in the underlying mineral soils.
3. The fallen acidic spruce needles are not fully decomposed and combine with the moss base. Water held in the moss carries the acid from the spruce needles into the mineral soil and leaches out soil nutrients – leaving a highly acidic, low nutrient soil base which is unsuitable for most boreal vegetation.
As a result of the above factors the forest floor ranges from nearly devoid of vegetation to a dense carpet of feather moss. A sparse community of shade tolerant shrubs exists in this environment. Some species of plants in the understory are Green Alder, low bush cranberry, prickly rose, bunchberry, twinflower, wild lily-of-the-valley, northern Comandra and wintergreens.
The mixedwood stands understory
There are several factors which influence the mixedwood stands in the boreal forest.
Where there are stands of aspen and spruce forests


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Discovery Ages 7-10 Lux. (Introduction)
No prior knowledge is required! Total of 10 lessons of 3 hours each.
Coding, robotics, curiosity and creativity! This new course is replacing the previous introduction course. The Discovery course sparks kids' interest in technology through engaging and fun activities. During these lessons, students will learn coding skills, develop their creativity and be inspired to explore their curiosity and tech interests. We will explore a variety of tech-related topics, such as: *What is technology *Basic concepts of coding (sequence, loop, debugging, etc) *How to code a game and an animation project in Scratch *How to code a robot (Botley, Dash, Sphero Ball, etc) *Logical thinking During the last course, the kids will present their favorite activities to their parents, which will also help them develop their communication skills. To participate in this course, the kids must speak and understand Luxembourgish. For working on the computer (reading / writing) is also possible in any other language supported on Scratch, for example English, French or German. No prior knowledge is required! A laptop is required (a mouse might also be useful).
- Started Oct 1Started Oct 1
- 450 euros450 €
- PwC 1, PwC Luxembourg, 2 Rue Gerhard Mercator, 2182 Luxembourg
Cancellation is possible up to one month before the course starts. Should you require any assistance or encounter any issues, please don't hesitate to reach out to us via email at _EMAIL_.
Kids Life Skills Contact Information


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When I built Paludarium 1.0, I was positive on having solved the water poisoning by not using potting soil anywhere in the landmass. As it turns out, the plants on land rot away leaves and build their own soil inside. Very nice for the plants, not so nice for the fish inside. since the water streams through the soil, it picks up a lot of chemicals that aren't very healthy for the fish in the aquatic part.
For the reason staed above I decided to build Paludarium 2.0 with two completely separated water households: One aquatic and one for the landmass. When I started to think up Paludarium 1.0 way back in 2005, I did not want to add this very complexity (I was thinking about a brackish aquatic part at the time). As it turns out, even without a brackish aquatic part, I still need separated water households. In this blogpost I'll sketch the first global design on these separated water households.
The basic requirements for the separated water households are pretty basic, and these determine the design that I'll make:
- Separate water households for the aquatic and the landmass part (obviously);
- Being able to add fresh tap water through reverse osmosis into the aquatic part, and spill any surplus to the landmass household;
- Spill any surplus water inside the landmass household directly into the sewer;
- Have a small pump for circulating (NOT fitering) the landmass water;
- Have a large external filter being able to filter the aquatic water household and stream out into a waterfall;
- The external tubing from and to the aquatic part should be injected just above the aquatic waterline, not though the ceiling of the paludarium (which is the case with the current setup).
Looking at all these requirements, I thought up a system similar to the one depicted below:
As you can see, some holes need to be drilled in the paludarium glass walls and bottom to get this working. The way it works: There are two wet zones: the Aquatic Zone and the Manure Zone, separated by a glass divider. Both store their respective water households.
Through the blue pipe the water is extracted from the aquatic zone of the paludarium. The water runs through the external filter, and is returned to the aquatic household through the red pipe. The reverse osmosis device delivers clean water which can be injected to the aquatic household through the purple pipe.
Any surplus water will spill over this separation wall into the manure water household. The green circulation pump inside this segment will pump up the water all the way to the top of the paludarium, and drizzle it down again along the back, straight back into the landmass water household.
Finally, any surplus water in the manure water zone is drained using the grey sewer pipe. This pipe is connected directly with the sewer system.
Heating the system
Heating is something to be considered. By inserting a heater into the red pipe, the aquatic zone can be heated to the right temperature (22-28 degrees centigrade). Since this zone is the biggest mass in the paludarium, it will effectively heat the air inside the paludarium to almost the same temperature. Secondly, the manure zone will also heat up to acceptable temperatures for plants living above the surface. I am not counting in rain (which comes from a separate tank kept at 18-20 degrees centigrade).
The reverse osmosis device will convert (the somewhat substandard) tap water into very clean cold water (10-15 degrees centigrade) into the aquatic zone and this might influence the temperature of this zone, possibly harming the fish. Also, the water coming from the reverse osmosis device is so pure, that it is actually poisonous to fish. However, the output of this device is rather small. These small amounts of fresh water will mix very gently with the water inside the aquatic zone, so the heater in that same segment should have no trouble heating this to an acceptable level. Also, this slow and gentle mixing should allow me to use this pure water because it will mix with the available water in the aquatic segment. If not, I'd need to inject chemicals to mix down the "overly clean" water into a "healthy" state for the fish inside. Should not pose any real problem.
Controlling it all
So now that the basic design is a fact, how do we go about automating this? I can start out simple: Both pumps need to run 24/7 anyway (bacteria inside the filter would die if it stopped and the plants above the surface would die if they did not get water from the circulation pump).
Heating can also be done very simple: The external heating could be set to any "fish friendly" temperature and the entire eco system inside would follow.
Finally, controlling the reverse osmosis device can be done by hand. When you would normally perform regular water changes in an aquarium, you'd now just open the valve for a few hours and the water would be changed automatically (and any surplus water would simply be ditched into the sewer). A big plus of this approach: the waterlevel is ALWAYS constant if I leave the tap open a tiny little bit (in a paludarium you can have massive evaporation).
It would be a nice feature though if I could utilize a channel from the current controllers to control an electric valve which automatically changes the water every x days for a duration of y hours
Automation in the next level: Sending measured data back to the automation unit?
In Paludarium 1.0, I never got round to automate up to a level where the controllers inside the paludarium (which are over 12!) can send measured data back to the paludarium. So there just was controlling, no data was sent back at all. If I could add this feature (the electronics SHOULD have support in their hardware but this was never tested) I'd be able to measure temperature of land and water, and control the heater accordingly. I could even vary it for night and day as I do have this data available (see the realtime status page). Also, I might be able to measure the conductivity of the water in the aquatic segment to determine how "dirty" it is and control the automatic water changing from there… Definitely something I will be trying to include when I work on the electronics in the future!


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- Category : SERVICE
A design review applies most commonly to new construction projects. Since mistakes in the design phase are the most costly to rectify, Design Review services makes sure that the design meets the intended functionality, performance and cost objectives of the data center.
The goals of the Design Review are mainly to:
- Catch early inconsistencies and discoordination in the project architecture and other engineering disciplines.
- Introduce data center best practices with the concept of operations and maintenance in mind.
- Performing value engineering without compromising reliability.
- Reduce the cost and risk of changes required later in the lifecycle.


Hope, Higher Energy, Healing
By Seamus Anthony
Successful people attract people to them because their story gives people hope that they too can be successful, whatever success means to them.
Higher Energy
People are attracted to the higher vibrations of successful people like moths to a flame. It is the energy that attracts them; they want to draw on this energy for themselves. They usually do not consciously know why they are attracted to successful people, but this is why: they want bask in that the Higher Energy that the successful person gives off, they want to soak it up for themselves. When the crowd goes to see the famous figure live, when they tune in to the TV to watch a celebrity being interviewed or when they read a success story it is pure energetic self-interest.
Self-interest explains away almost all of human behaviour, good or bad.
Tuning into this Higher Energy heals people's wounds. And, via art (music, poetry, paintings, movies, etc) the expression of pain, conflict and difficult emotions (in the art) helps people to acknowledge and identify with their own emotional baggage.
Knowing and relating to other people's pain helps us to feel better about our own lives. And for many of us, the different art forms, music especially, helps us to heal by expressing what we don't fully know how to self-express.
Feel free to slurp on the higher energy in my new music video, Monkey Mind…
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Friday 17 May
Mexican cantil (Agkistrodon bilineatus)
Mexican cantil fact file
- Find out more
- Print factsheet
Mexican cantil description
The Mexican cantil is a venomous pitviper that is greatly feared by humans throughout its range (2). Like all pitvipers, the Mexican cantil has a pair of heat-sensitive pits, located between the eye and nostril on each side of the head (2). Its body is a dark brown ground colour, overlaid with darker brown or black bands, often fringed with white or cream scales (2). Juvenile cantils usually possess more distinctive banding and brightly coloured tails, used to lure prey (2) (4).
The generic name, Agkistrodon, is derived from the Greek Ancistro,meaning 'hook', and odon, meaning 'tooth', referring to the hinged, hollow fangs of this species (2). The Mexican cantil has the longest fangs of any species within the Agkistrodon genus, growing to over one centimetre in length (2). The specific name, bilineatus, refers to the pair of striking pale stripes on each side of the head: bi-means 'two' and lineatus means 'lined' in Latin (2).
- Also known as
- cantil, Mexican moccasin.
- Cantil, Castellana. Top
International Reptile Conservation Foundation:
Amphibian and Reptile Conservation:
- Generic name
- The first of the two scientific names by which an animal is identified. An animal's scientific name is the same throughout the world, although it may have different common names in different countries and languages.
- A category used in taxonomy, which is below 'family' and above 'species'. A genus tends to contain species that have characteristics in common. The genus forms the first part of a 'binomial' Latin species name; the second part is the specific name.
- An animal with no backbone. Invertebrates include insects, crustaceans, worms, molluscs and spiders.
- Specific name
- The second of the two scientific names by which an animal is identified.
- A population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.
- Animals with a backbone.
IUCN Red List (November, 2009)
- Campbell, J.A. and Lamar, W.W. (2004) The Venomous Reptiles of the Western Hemisphere. Cornell University Press, New York.
- Parkinson, C.L., Zamudio, K.R. and Greene, H.W. (2000) Phylogeography of the pitviper clade Agkistrodon: historical ecology, species status, and conservation of cantils. Molecular Ecology, 9: 411-420.
- Greene, H.W. (1992) The ecological and behavioral context for pitviper evolution. In: Campbell, J.A. and Brodie, E.D. (Eds.) Biology of the Pitvipers. Selva, Tyler, Texas.
- Gloyd, H.K., and Conant, R. (1990) Snakes of the Agkistrodon Complex: A Monographic Review. Society for the Study of Amphibians and Reptiles, St. Louis, Missouri.
- Bogert, C.M., and Oliver, J.A. (1945) A preliminary analysis of the herpetofauna of Sonora. Bulletin of the American Museum of Natural History, 109: 1-238.
- Allen, E.R. (1949) Observations on the feeding habits of the juvenile cantil. Copeia, 1949(3): 225-226.
CITES (November, 2009)
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Mexican cantil biology
The diverse habitats occupied by the Mexican cantil throughout its range suggest it is a semi-aquatic species (2). Individuals have been recorded swimming in streams, marshes and even roadside ditches after nightfall, and the majority of evidence indicates that this species is primarily active at night (2). Adult cantils prey upon a variety of vertebrates, including amphibians, reptiles, birds and mammals (2), and there is a single record of a treesnake being consumed (6). Juveniles lure potential prey by 'wiggling' the bright yellow tail as if to mimic an invertebrate, attracting frogs and lizards (2) (7).
The Mexican cantil gives birth to live young (2). Mating usually occurs between December and April, with individuals giving birth from June until August, during the rainy season (2). There are usually five to ten young in a litter, although extremes of three to twenty have been recorded (2).Top
Mexican cantil range
The Mexican cantil is comprised of three geographically distinct subspecies (2) (3). The subspecies Agkistrodon bilineatus bilineatus occurs along the Pacific coast of Central America, from southern Sonora, Mexico, through Guatemala to El Salvador (5). Agkistrodon bilineatus howardgloydi is distributed throughout north-western Costa Rica and western Nicaragua, and has a limited range in El Salvador and Honduras (5). Agkistrodon bilineatus russeolusis found in northern Belize and the Yucatán Peninsula, Mexico (5).Top
Mexican cantil habitat
The Mexican cantil occurs in a vast range of habitats, including seasonally dry forest, tropical deciduous forest, tropical scrub forest and savanna (2). Habitat bordering rivers or streams is preferred, but it may also occur in grasslands and cultivated lands (1).Top
Mexican cantil status
Classified as Near Threatened (NT) on the IUCN Red List (1).Top
Mexican cantil threats
Despite its extensive distribution throughout Central America, the Mexican cantil is one of the most endangered snakes in the Americas (2). This is due to the conversion of tropical forest and thorn scrub for agricultural purposes (5), combined with human persecution throughout its fragmented range (1). Populations have suffered declines of nearly 30 percent over the past 30 years and, sadly, populations continue to decrease today (1).Top
Mexican cantil conservation
The Mexican cantil occurs in two protected areas in Mexico: the Calakmul Biosphere Reserve and the Chamela Biological Station (1). The species is not currently afforded any protection from international trade by the Convention on International Trade in Endangered Species (CITES) (8).Top
Find out more
To learn about efforts to conserve snakes around the world see:
This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
More »Related species
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|This centre is a member of The LSE Research Laboratory [RLAB]: CASE | CEE | CEP | FMG | SERC | STICERD||Cookies?|
Paper No' CEPDP0625: | Full paper
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Keywords: Human capital; Economic Impact, Personal Computers
JEL Classification: I2; J2; J13; J24
Is hard copy/paper copy available? YES - Paper Copy Still In Print.
This Paper is published under the following series: CEP Discussion Papers
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Abstract:If personal computers (PCs) are used to enhance learning and information gathering across a variety of subjects, then a home computer might reasonably be considered an input in an educational production function. Using data on British youths from the British Household Panel Survey between 1991 and 2001, this paper attempts to explore the link between ownership of a home computer at ages 15 and 17 and subsequent educational attainment in the principal British school examinations taken at ages 16 (GCSEs) and 18 (A levels). The data show a significant positive associatio n between PC ownership and both the number of GCSEs obtained and the probability of passing five or more GCSEs. These results survive a set of individual, household, and area controls, including using other household durables and \'future\' PC ownership as proxies for household wealth and other unobservable household level effects. Home computer ownership is also associated with a significant increase in the probability of passing at least one A level conditional on having passed five and increase in the probability of successfully completing three or more A levels, conditional on having passed at least one A level.
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Web Content Display
Web Content Display
Process description
Messer solution
When packaging under a modified atmosphere a variety of gases are used, for example carbon dioxide (CO2), argon (Ar), nitrogen (N2) or oxygen (O2).
In addition to displacing the ambient atmosphere, protective gases can reduce the oxidative changes to foodstuffs and microbial activity.
A modified atmosphere offers the following advantages:
 - Extended shelf-life
 - Longer preservation of sensory properties such as appearance or taste
 - Reduction in microbiological activity in product
 Example of a tray sealer