The 'linebreak' option can be set to wrap at a blank character.
If the window has room after the last line of the buffer, Vim will show '~' in
the first column of the last lines in the window, like this:
 |some line |
 |last line |
 |~ |
 |~ |
Thus the '~' lines indicate that the end of the buffer was reached.
If the last line in a window doesn't fit, Vim will indicate this with a '@' in
 |first line |
 |second line |
 |@ |
 |@ |
Thus the '@' lines indicate that there is a line that doesn't fit in the
When the "lastline" flag is present in the 'display' option, you will not see
'@' characters at the left side of window. If the last line doesn't fit
completely, only the part that fits is shown, and the last three characters of
the last line are replaced with "@@@", like this:
 |first line |
 |second line |
 |a very long line that d|
 |oesn't fit in the wi@@@|
If there is a single line that is too long to fit in the window, this is a
special situation. Vim will show only part of the line, around where the
cursor is. There are no special characters shown, so that you can edit all
parts of this line.
{Vi: gives an "internal error" on lines that do not fit in the window}
The '@' occasion in the 'highlight' option can be used to set special
highlighting for the '@' and '~' characters. This makes it possible to
distinguish them from real characters in the buffer.
The'showbreak' option contains the string to put in front of wrapped lines.
If the 'wrap' option is off, long lines will not wrap. Only the part that
fits on the screen is shown. If the cursor is moved to a part of the line
that is not shown, the screen is scrolled horizontally. The advantage of
this method is that columns are shown as they are and lines that cannot fit
on the screen can be edited. The disadvantage is that you cannot see all the
characters of a line at once. The'sidescroll' option can be set to the
minimal number of columns to scroll. {Vi: has no 'wrap' option}
All normal ASCII characters are displayed directly on the screen. The
is replaced with the number of spaces that it represents. Other non-printing
characters are replaced with "^{char}", where {char} is the non-printing
character with 64 added. Thus character 7 (bell) will be shown as "^G".
Characters between 127 and 160 are replaced with "~{char}", where {char} is
the character with 64 subtracted. These characters occupy more than one
position on the screen. The cursor can only be positioned on the first one.
If you set the 'number' option, all lines will be preceded with their
number. Tip: If you don't like wrapping lines to mix with the line numbers,
set the'showbreak' option to eight spaces:
 ":set showbreak=\ \ \ \ \ \ \ \ "
If you set the 'list' option, characters will not be shown as several
spaces, but as "^I". A '$' will be placed at the end of the line, so you can
find trailing blanks.
In Command-line mode only the command-line itself is shown correctly. The
display of the buffer contents is updated as soon as you go back to Command
The last line of the window is used for status and other messages. The
status messages will only be used if an option is on:
status message option default Unix default
current mode 'showmode' on on
command characters 'showcmd' on off
cursor position 'ruler' off off
The current mode is "-- INSERT --" or "-- REPLACE --", see |'showmode'|. The
command characters are those that you typed but were not used yet. {Vi: does
not show the characters you typed or the cursor position}
If you have a slow terminal you can switch off the status messages to speed
up editing:
 :set nosc noru nosm
If there is an error, an error message will be shown for at least one second
(in reverse video). {Vi: error messages may be overwritten with other
messages before you have a chance to read them}
Some commands show how many lines were affected. Above which threshold this
happens can be controlled with the'report' option (default 2).
On the Amiga Vim will run in a CLI window. The name Vim and the full name of
the current file name will be shown in the title bar. When the window is
resized, Vim will automatically redraw the window. You may make the window as
small as you like, but if it gets too small not a single line will fit in it.
Make it at least 40 characters wide to be able to read most messages on the
last line.
On most Unix systems, resizing the window is recognized and handled correctly
by Vim. {Vi: not ok}
8. Definitions *definitions*
 screen The whole area that Vim uses to work in. This can be
 a terminal emulator window. Also called "the Vim
 window A view on a buffer.
A screen contains one or more windows, separated by status lines and with the
command line at the bottom.
screen | window 1 | window 2 |
 | | |
 | | |
 |= status line =|= status line =|
 | window 3 |
 | |
 | |
 |==== status line ==============|
 |command line |
The command line is also used for messages. It scrolls up the screen when
there is not enough room in the command line.
A difference is made between four types of lines:
 buffer lines The lines in the buffer. This is the same as the
 lines as they are read from/written to a file. They
 can be thousands of characters long.
 logical lines The buffer lines with folding applied. Buffer lines
 in a closed fold are changed to a single logical line:
 "+-- 99 lines folded". They can be thousands of
 characters long.
 window lines The lines displayed in a window: A range of logical
 lines with wrapping, line breaks, etc. applied. They
 can only be as long as the width of the window allows,
 longer lines are wrapped or truncated.
 screen lines The lines of the screen that Vim uses. Consists of
 the window lines of all windows, with status lines
 and the command line added. They can only be as long
 as the width of the screen allows. When the command
 line gets longer it wraps and lines are scrolled to
 make room.
buffer lines logical lines window lines screen lines
1. one 1. one 1. +-- folded 1. +-- folded
2. two 2. +-- folded 2. five 2. five
3. three 3. five 3. six 3. six
4. four 4. six 4. seven 4. seven
5. five 5. seven 5. === status line ===
6. six 6. aaa
7. seven 7. bbb
 8. ccc ccc c
1. aaa 1. aaa 1. aaa 9. cc
2. bbb 2. bbb 2. bbb 10. ddd
3. ccc ccc ccc 3. ccc ccc ccc 3. ccc ccc c 11. ~
4. ddd 4. ddd 4. cc 12. === status line ===
 5. ddd 13. (command line)
 6. ~
top - main help file
Help FAQ Both


text:
The i-Pro's Radial Consistency
Radial consistency is the shaft's ability to reproduce the same results, regardless of its orientation. This means the shaft will perform more predictably from shot to shot. The i-Pro's Octadic Laminated Shaft Construction, combined with its Triple-Layer Carbon Fiber Core, makes it the most radial consistent shaft we've ever made.
Octadic Laminated Shaft Construction
The Octadic Laminated Shaft Construction features eight spliced pieces of premium maple that are bonded together to form our most radial consistent shaft yet. This construction method drastically reduces the performance inconsistencies caused by natural wood grain. This technology maximizes energy transfer from the shaft into the cue ball at impact, allowing you to generate a higher spin rate while hitting closer to center cue ball.
Triple-Layer Carbon Fiber Core
The i-Pro's Triple-Layer Carbon Fiber Core extends the full-length of the shaft (from ferrule to joint), stabilizing the entire shaft for absolute control and predictability. This technology increases radial consistency, reduces vibration and virtually eliminates the inconsistencies found in a traditional maple shaft.

source: openbmb/Ultra-FineWeb


text:
Points or principles? Which will you teach the next time you get together with your Bible study group? In a classic work by John Bisagno, he encourages the preaching and teaching of God's Word by focusing on principles, not points. Bisagno says the following:
"I consider this to be a very important part of my preaching ministry. I learned it from Rick Warren some years ago and believed it so firmly that I made a conscious decision to change my preaching style. I consider it simple but profound: The outline should consist of principles, not points" (Letters to Timothy, p.157).
In this same book, Bisagno goes on to help preacher-teachers understand how to more effectively teach God's Word. Here are more of his thoughts on teaching points and principles:
3 Reasons Why Points are Puny:
- Points are predictable. How many times have you filled in the blanks on a preacher's outline before he told you the answer?
- Points tend to turn off the listener because they are predictable. If your mind races ahead to fill in the blanks in an outline, you'll miss what the communicator says in the present.
- Points don't inspire or capture the imagination. Minds wander. Attention spans are short. Teachers/preachers/communicators are always fighting to keep people's attention. Points aren't the best option for capturing wandering minds.
4 Steps in Teaching Principle-Centered Lessons
- State the principle – this is simple and straightforward. Simply tell the class what the principle says, show it to them in an outline, write it on the board, etc.
- Explain the principle – spend a good amount of time here….this is where your explanation is an exegesis of the passage; use many sources like customs, original languages, quotations, etc. Anticipate the question and answer him in the explanation.
- Apply the principle – the Holy Spirit really helps you at this stage; He applies the truth to your learner's hearts. We don't help Him teach….He helps us teach! Articulate how it applies to your group members. It may be stating the obvious, but reinforcing what the Spirit is already saying to people's hearts strengthens the truth.
- Illustrate the principle – don't reach way back into history for illustrations (no one cares about Baron von So-and-So from the 14th century). Use current illustrations from books, movies, TV shows, the newspaper, and sources like Newsweek, Time, USA Today, People, etc. Stories help younger audiences connect their heart to your message…become a great storyteller


text:
U.S. Joins International Effort to Promote Environmental Journalism to Today's Youth
NWF recruits middle and high school students to participate in annual competition
As the United States host of the international Young Reporters for the Environment program, the National Wildlife Federation has started recruiting public, private and charter middle and high school students in the U.S. to participate in an annual competition that encourages and promotes youth environmental journalism.
The new Young Reporters for the Environment USA (YRE-USA) program is part of a rapidly-growing international network of international youth engaged in Education for Sustainable Development (ESD). It is coordinated by the Foundation for Environmental Education and currently operates in more than 25 countries. The United States is one of the more recent countries to join this effort.
"This youth environmental journalism program helps to develop participants' skills and knowledge, enhances communication and citizenship skills, individual initiative, team work, critical analysis, social responsibility, and leadership," said Laura Hickey, Senior Director of Eco-Schools USA and YRE-USA for the National Wildlife Federation.
Students that participate in the program investigate a local environmental problem or issue, and propose solutions. They document their work and report on it through a journalistic production targeting a local audience. These journalistic efforts can be through the creation of an article, a photograph, a photographic essay, or a video which is then shared with a local audience through a variety of media.
The Young Reporters for the Environment program is both a national and an international competition. Winning national entries compete against other countries' entries for recognition and prizes, and both competitions utilize independent juries to make the winning selections. Full contest rules can be found on the YRE-USA website.
Teachers are encouraged to use YRE as a cross-curriculum tool to make learning more fun and to help students investigate relevant issues and create submissions developed in different subjects. There are two age categories in the US-based YRE program: 13-15, and 16-18. The first place article, photograph/photographic essay, and video from each category will be submitted to the international competition.
The YRE-USA website has suggested topics, definitions, links, and resources for budding young journalists, as well as information about the national and international competition. Young Reporters for the Environment USA is a free program hosted by the National Wildlife Federation.
To learn more about YRE-USA or to register, go to _URL_.

source: HuggingFaceFW/fineweb-edu


text:
DEERFIELD, Ill., Jan. 7 (UPI) -- An early ancestor of today's birds had teeth -- and not just any teeth, but ones evolved for a special diet, U.S. paleontologists say.
Writing in the Journal of Vertebrate Paleontology, researchers say a study of a species of early bird, Sulcavis geeorum, suggests it had a durophagous diet, meaning the bird's teeth were capable of eating prey with hard exoskeletons like insects or crabs.
The new specimen, a fossil from the the Early Cretaceous period of 121 million to 125 million years ago, greatly increases the known diversity of tooth shape in early birds and hints at previously unrecognized ecological diversity, they said.
The fossil from an early group of birds known as enantiornithines was found in China and has robust teeth with grooves on the inside surface that likely made them stronger to deal with harder food items, researchers said.
No previous bird species have been found with such grooves, ridges, striations, serrated edges or any other form of dental ornamentation, researchers said.
"While other birds were losing their teeth, enantiornithines were evolving new morphologies and dental specializations," lead study author Jingmai O'Connor said.
"We still don't understand why enantiornithines were so successful in the Cretaceous but then died out -- maybe differences in diet played a part."
|Additional Science News Stories|


_USER_ {11089, title = {Benchmarking wide swath altimetry-based river discharge estimation algorithms for the Ganges river system}, journal = {Water Resources Research}, volume = {52}, year = {2016}, month = {04/2016}, pages = {2439-2461}, chapter = {2439}, abstract = {
The objective of this study is to compare the effectiveness of three algorithms that estimate discharge from remotely sensed observables (river width, water surface height, and water surface slope) in anticipation of the forthcoming NASA/CNES Surface Water and Ocean Topography (SWOT) mission. SWOT promises to provide these measurements simultaneously, and the river discharge algorithms included here are designed to work with these data. Two algorithms were built around Manning\&$\#$39;s equation, the Metropolis Manning (MetroMan) method, and the Mean Flow and Geomorphology (MFG) method, and one approach uses hydraulic geometry to estimate discharge, the at-many-stations hydraulic geometry (AMHG) method. A well-calibrated and ground-truthed hydrodynamic model of the Ganges river system (HEC-RAS) was used as reference for three rivers from the Ganges River Delta: the main stem of Ganges, the Arial-Khan, and the Mohananda Rivers. The high seasonal variability of these rivers due to the Monsoon presented a unique opportunity to thoroughly assess the discharge algorithms in light of typical monsoon regime rivers. It was found that the MFG method provides the most accurate discharge estimations in most cases, with an average relative root-mean-squared error (RRMSE) across all three reaches of 35.5\%. It is followed closely by the Metropolis Manning algorithm, with an average RRMSE of 51.5\%. However, the MFG method\&$\#$39;s reliance on knowledge of prior river discharge limits its application on ungauged rivers. In terms of input data requirement at ungauged regions with no prior records, the Metropolis Manning algorithm provides a more practical alternative over a region that is lacking in historical observations as the algorithm requires less ancillary data. The AMHG algorithm, while requiring the least prior river data, provided the least accurate discharge measurements with an average wet and dry season RRMSE of 79.8\% and 119.1\%, respectively, across all rivers studied. This poor performance is directly traced to poor estimation of AMHG via a remotely sensed proxy, and results improve commensurate with MFG and MetroMan when prior AMHG information is given to the method. Therefore, we cannot recommend use of AMHG without inclusion of this prior information, at least for the studied rivers. The dry season discharge (within-bank flow) was captured well by all methods, while the wet season (floodplain flow) appeared more challenging. The picture that emerges from this study is that a multialgorithm approach may be appropriate during flood inundation periods in Ganges Delta.
}, keywords = {delta, discharge, floods, Ganges river system, satellite remote sensing, SWOT mission}, doi = {10.1002/2015WR017296}, author = {Bonnema, Matthew G. and Sikder, Safat and Hossain, Faisal and Durand, Michael and Gleason, Colin J. and Bjerklie, David M.} } _USER_ {11353, title = {Characterizing supraglacial meltwater channel hydraulics on the Greenland Ice Sheet from in situ observations}, journal = {Earth Surface Processes and Landforms}, volume = {41}, year = {2016}, month = {11/2016}, pages = {2111-2122}, chapter = {2111}, abstract = {
}, keywords = {fluvial geomorphology, GIS, Greenland Ice Sheet, stream order, WorldView-1/2}, doi = {10.1080/_PHONE_.2016._PHONE_}, author = {Yang, Kang and Smith, Laurence C. and Chu, Vena W. and Pitcher, Lincoln H. and Gleason, Colin J. and Rennermalm, Asa K. and Li, Manchun} } _USER_ {10981, title = {Intercomparison of remote sensing river discharge estimation algorithms from measurements of river height, width, and slope}, journal = {Water Resources Research}, volume = {52}, year = {2016}, month = {06/2016}, pages = {4527{\textendash}4549}, chapter = {4527}, abstract = {
The Surface Water and Ocean Topography (SWOT) satellite mission planned for launch in 2020 will map river elevations and inundated area globally for rivers \>100 m wide. In advance of this launch, we here evaluated the possibility of estimating discharge in ungauged rivers using synthetic, daily \"remote sensing\" measurements derived from hydraulic models corrupted with minimal observational errors. Five discharge algorithms were evaluated, as well as the median of the five, for 19 rivers spanning a range of hydraulic and geomorphic conditions. Reliance upon a priori information, and thus applicability to truly ungauged reaches, varied among algorithms: one algorithm employed only global limits on velocity and depth, while the other algorithms relied on globally available prior estimates of discharge. We found at least one algorithm able to estimate instantaneous discharge to within 35\% relative root-mean-squared error (RRMSE) on 14/16 nonbraided rivers despite out-of-bank flows, multichannel planforms, and backwater effects. Moreover, we found RRMSE was often dominated by bias; the median standard deviation of relative residuals across the 16 nonbraided rivers was only 12.5\%. SWOT discharge algorithm progress is therefore encouraging, yet future efforts should consider incorporating ancillary data or multialgorithm synergy to improve results.
}, keywords = {discharge algorithms; remote sensing of rivers; SWOT}, doi = {10.1002/2015WR018434}, author = {Gleason, Colin J. and Durand, Michael and Garambois, P.A. and Bjerklie, David M. and Smith, Laurence C. and Roux, H. and Rodriguez, E. and Bates, P. and Pavelsky, T.M. and Monnier, J. and Chen, X. and Di Baldassarre, G. and Friset, J.-M. and Flipo, N. and Frasson, R.P.d.M. and Fulton, J. and Goutal, N. and Hossain, F. and Humphries, E. and Minear, J.T. and Mukolwe, M.M. and Neal, J.C. and Ricci, S. and Sanders, B.F. and Schumann, G. and Schubert, J.E. and Vilmin, L.} } _USER_ {11138, title = {A caution on the use of surface digital elevation models to simulate supraglacial hydrology of the Greenland ice sheet}, journal = {IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing }, volume = {8}, year = {2015}, month = {10/15}, pages = {5212-5224}, chapter = {5212}, abstract = {
}, keywords = {Digital elevation model (DEM), Greenland ice sheet (GrIS), hydrology, supraglacial lake, supraglacial river}, issn = {_PHONE_}, doi = {10.1109/JSTARS.2015._PHONE_}, author = {Yang, Kang and Smith, Laurence C. and Chu, Vena W. and Gleason, Colin J. and Li, Manchun} } _USER_ {11431, title = {Crossing the (watershed) divide: Satellite data and the changing politics of international river basins}, journal = {The Geographical Journal}, year = {2015}, month = {09/2015}, abstract = {
Acquiring freshwater resources is a necessary component of sustainable human settlement subject to increasing pressure from population and climate changes. This sometimes scarce resource primarily comes from rivers, and international river basins (IRBs), where watersheds and watercourses cross political boundaries, are often spaces of great political tension and conflict worldwide. Such conflict potential has garnered interest from a wide range of research communities, and each emphasises public access to hydrologic data as integral to successful international management of IRBs. However; these hydrologic data, especially measurements of river flow rate, are often closely guarded state secrets. Satellites have been cited as a key technology set to challenge this data monopoly that have yet been unable to calculate river flow rate without some form of guarded ancillary data. Now, at-many-stations hydraulic geometry (AMHG) offers a means of circumventing data limitations without any\ a priori\ information, and the forthcoming NASA/CNES Surface Water and Ocean Topography (SWOT) satellite also promises to estimate flow rates solely from its novel measurements following launch. In this paper, we explore how these newly available estimates of river flow rate could reconfigure water-management and interstate relations in IRBs, and demonstrate AMHG, for two cases: the Ganges\–Brahmaputra and Mekong. For these basins we find that satellite flow rate retrievals will likely reinforce and favour state-level negotiations of water resource governance. Also, satellite flow retrievals can have the direct, concrete effect of improving hydrologic understanding of the upstream Ganges\–Brahmaputra, a sorely


text:
عنوان مقاله [English]
نویسنده [English]چکیده [English]
The question of truth in both practical and theoretical reason is raised. And attempts to ignore it have not been compelling and efficient. Human access to truth is a complex process which, as Kant observed, that in addition to sensory data are needed to concepts such as causality. And concepts did not derive from the human individual effort but are the results of human culture and collective work. So our efforts to attain to knowledge is dependent on other people, and therefore, to the common mentality. This means that the role of "discourse" in our knowledge of the world; in other words, knowledge is achieved in a process of dialogue. Naturally, this process has conditions and laws that arises in the logic of dialogue. This set of rules forms an ethics of knowledge that is that a formal system of reference for conflict resolution. This code is applicable not only in access to knowledge but it can be extended to the field of individual and collective human actions to solve problems of human. That is how human to avoid violence and war leads to dialogue as a promising process for resolving human problems.


text:
To run newlead, you need to 1) Create a folder (e.g., C:\Newlead) and copy two folders: data bin from the unzipped distribution there. 2) define the NEWLEAD_ROOT environment variable as the location of the data folder, and add the location of the bin folder to the "Path". Environment Variable ==================== The instructions on how to add Environment Variables under Windows can be found by searching Google:
windows environment variables,for example: _URL_ To view or change environment variables: 1. Right-click My Computer, and then click Properties. 2. Click the Advanced tab. 3. Click Environment variables. 4. Click one the following options, for either a user or a system variable: * Click New to add a new variable name and value. * Click an existing variable, and then click Edit to change its name or value. * Click an existing variable, and then click Delete to remove it. For the example given in 1), the NEWLEAD_ROOT variable would be: NEWLEAD_ROOT=C:\Newlead\data Path ==== The %Path% is one of Window's Environment Variables. Instructions on how to change %Path% under Windows can be found by searching Google: windows path variable,for example, at: _URL_ _URL_ Essentially, %PATH% is one of windows environment variables, and if you follow instructions above for setting %NEWLEAD_ROOT%, just Edit the %PATH% variable, append the location of bin folder (e.g.: C:\Newlead\bin) using a semicolon (;) as a separator.


text:
Dr Ryan Farquharson1, Dr Jeff Baldock1, Dr Uta Stockmann2, Dr Lynne Macdonald1, Dr Brendan Malone2, Mrs Seija Tuomi2, Mr David Benn3
1CSIRO Agriculture and Food, Glen Osmond, Australia, 2CSIRO Agricuture and Food, Acton, Australia, 3CSIRO IM&T, Glen Osmond, Australia
Infrared (IR) spectroscopy can provide estimates of the quantities of organic carbon in soil as well as its allocation to fractions isolated and measured by physical and chemical means. Rapid and cost-effective estimates of a range of soil properties by IR spectroscopy allow more samples to be analysed, making the acquisition of large data sets feasible, as exemplified by the national soil carbon dataset collected by the Australian Soil Carbon Research Program. These data sets open up a number of opportunities for spatial modelling at a range of scales and for monitoring of soil condition, with applications in greenhouse gas accounting and mitigation, and management of resources in agricultural enterprises, for example. Here we present a roadmap to take this technology out of the research domain and make it available to a range of users. By combining measurement, prediction and modelling, and creating a system where information flow is circular, synergistic benefits to both end users and technology developers will be realised. For example, analysis of spectra in real time might identify samples for which current prediction algorithms are unreliable, which can then be further analysed and added to calibration sets, potentially providing the end user with more reliable results. Land managers make multiple decisions that balance a number of objectives, including productivity, sustainability and profitability. In the soil organic matter space, we recognise that carbon fractions are just one of many pieces of information that need to be brought together into a decision support framework. To do so will require a concerted effort involving a range of players including researchers, analytical laboratories, data scientists, software engineers, government departments, advisory bodies, agronomists, grower groups, industry and funding bodies. We hope that by articulating a roadmap we can bring these players together and expedite the path to impact for soil spectroscopy.
Ryan Farquharson is an Experimental Scientist in the Carbon and Nutrient Cycling group at CSIRO Agriculture and Food. Based at the Waite Campus in Adelaide since 2002, his research interests include greenhouse gas balances of agricultural systems, modelling approaches for greenhouse gas inventories and life cycle analysis, biological nitrogen fixation by the legume/rhizobium symbiosis and more recently, the use of infrared spectroscopy for a range of applications in soil, including quantifying soil carbon.


Scientists Turn To Seahorses For Nearly Unbreakable Limbs
Researchers at Clemson University have created a new sort of robotic design based on the long, curled tail of the seahorse. The seahorse is unique because it consists of "square prisms surrounded by bony plates that are connected by joints." Other animal tails are cylindrical and therefore easily crushed.
The researchers write:
￼Researchers found that the square prototype was stiffer, stronger and more resilient than the circular one when crushed. The square prototype was about half as able to twist, a restriction that could prevent damage to the seahorse and give it better control when it grabs things.Both prototypes could bend about 90 degrees, although the cylindrical version was slightly less restricted.
There are a few popular biomimetic robotic snakes on the market but this design would allow a robot to fold up without losing structural integrity. The robotic seahorse could withstand a solid whacking with a hammer while similar cylindrical designs folded at the point of impact.


text:
Import AUTOSAR architecture updates from OEMs
Select this option before the import to merge data instead of overwriting it.
The splittable mechanism provides the following benefits:
- You can optimize processes by distributing elements to files as required, e.g., to support processes for data exchange between OEMs and suppliers.
- You can add elements to an AUTOSAR model via additional AUTOSAR files. This lets you add elements without changing existing AUTOSAR files.
- To reimport splittable elements, right-click the project node and select Import – AUTOSAR.
- Select the file you want to import and select Files contain a new system extract version with splittable elements.
- Browse to and select the previous file version for comparison. SystemDesk returns to the Import dialog.
- Click Start Import.
SystemDesk imports and merges the selected AUTOSAR elements.
You merged AUTOSAR elements from an AUTOSAR file with the AUTOSAR elements in a SystemDesk project.


text:
Tracking the Hotrod Trace the optimal trajectory for the hotrod example with the initial conditions given in Problem. This may require sketching trajectories that are not shown in Fig. 7, but are in the families of those trajectories shown. The sketches should resemble those in Fig.
(x0, ẋ0) = (3, −1)


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Topic: Sharing a thermister (Read 682 times) previous topic - next topic
I was curious if something like this will work!
+ shared to two arduinos
- to one arduino, and grounds connected to the arduinos together.
Then I can have a 10k resister on the + of the thermister at each side and have no differences in reading at each side?
10K Thermister has one side of Analog Input 1 from two arduinos connected (A1 from Arduino 1, A1 from Arduino 2). The other side goes to ground on one of the arduinos, and both arduinos have the grounds connected together.
Would the measurement of temperature at each one then be identical?
What I want to do is similar, I'm just curious if something like that would work? The reason I ask is I gather a thermister connection requires readings from the mid point of a 10k circuit (i.e. thermister on one side, 10k resister on the other, temperature reading is at the mid point of that).
It was suggested to use UnityGain Amplifier - not sure how that works for it's input?
Whilst looking in to op amps, I came across this page, now will I be able to take the Positive side of the thermister and use some sort of following circuit to SHARE the input with both controllers?
The analog input is just sensing a voltage - so long as the supplies and ground are the same you should get the same reading (+/- about one LSB).
[ I won't respond to messages, use the forum please ]
Well it senses resistance right?
That's what the problem will be I thought?
So, if I instead - use the resistance measurement circuit on one controller, and the other, I take that same midpoint and use a op amp in a unity follower setup - with a common ground reference that would work I take it?
If I take the resistance measurements directly, and output the measurements to a digital pot, would that work?
So, in the place of the current thermistor on the old circuit, I put the output of a DS1803 digital pot.
Will that work? There's a 10k resister in the way though, so does that need to get removed? Does a DS1803 get directly connected to ground and the analog input or does it also require a 10k resister?
For this I plan on using a TL072 to follow the voltage.
I just want to be clear on how I'll connect - the TL072 + input is the same + from the thermistor (before the resistors?), and then I input this to an analog input on the arduino (or do I also need to get the output of TL072 to the resistor first to get the same result as both controllers?)
I plan on doing some tests, but would like to be sure...
Does having a thermistor on all the time use a lot of current? Will the result of a thermistor be different if you only power it for a few microseconds before reading, when needed instead?
Depends on the resistance of the thermistor and the voltage passing thru it.
You will have the thermistor in a voltage divider: _URL_
So add the resistances in series and calculate power with P = V*V/R.
You should be able to share the thermistor but I'd use a cap to ground from the thermistor/divider output to reduce input impedance.
That was the reason it was suggested to use TL072 - it has a very high impedance so as to not cause interference on the circuit.
With respect to the capacitor - I'm not sure where I should pick up the input from the thermistor?
I can get it from before the resistors on the other side, or after it - in fact I could go as far back as the MCU that's reading it - is that the ideal place to measure from?
What will happen is I'll get the voltage reading and build an array of the voltage to temperature values and that should give me close enough to a reference of the temperature being read by the other controller..
What I think will work is:
Thermistor -> Existing controller.
Then solder to the existing input (either at the thermistor, before the resistors, or after the resistors, at the MCU), cable to bring it out to TL072 Op Amp following the voltage reading.
The TL072 as a voltage follower will feed the same voltage reading into my Arduino and it will reference it's table of voltages to decide what temperature it is.
So, do I get the TL072 input from the + of the thermistor (i.e. the field side of the thermistor), or from the MCU side which will be after the resistor (i.e. the midpoint)?
You want to measure at the midpoint as that is the output of the divider.
If you measure without the divider, you will be measuring the supply voltage on the other side of the thermistor, not what you want...
Take a look at the picture at the top of this post:
This is for measuring battery voltage, but in your case R1 or R2 will be a thermistor and the voltage will vary with temperature.
The post explains the need for the capacitor and the math to calculate the output voltage as well...
Go Up


text:
Neuropsychology Abstract of the Day
Department of Internal Medicine and Epidemiology, New Haven, Connecticut 06504, USA.
OBJECTIVES: To determine the priority that older adults with coexisting hypertension and fall risk give to optimizing cardiovascular outcomes versus falland medication symptom-related outcomes. DESIGN: Interview. SETTING: Community. PARTICIPANTS: One hundred twenty-three cognitively intact persons aged 70 and older with hypertension and fall risk. MEASUREMENTS: Discrete choice task was used to elicit the relative importance placed on reducing the risk of three outcomes: cardiovascular events, serious fall injuries, and medication symptoms. Risk estimates with and without antihypertensive medications were obtained from the literature. Participants chose between 11 pairs of options that displayed lower risks for one or two outcomes and a higher risk for the other outcome(s), versus the reverse. Results were used to calculate relative importance scores for the three outcomes. These scores, which sum to 100, reflect the relative priority participants placed on the difference between the risk estimates of each outcome. RESULTS: Sixty-two participants (50.4%) placed greater importance on reducing risk of cardiovascular events than reducing risk of the combination of fall injuries and medication symptoms; 61 participants did the converse. A lower percentage of participants with chronic obstructive pulmonary disease (P=.02), unsteadiness (P=.02), functional dependency (P=.04), lower cognition (P=.02) and depressive symptoms (P=.03) prioritized cardiovascular outcomes over fall injuries and medication symptoms than did participants without these characteristics. CONCLUSION: Interindividual variability in the face of competing outcomes supports individualizing decision-making to individual priorities. In the current example, this may mean forgoing antihypertensive medications or compromising on blood pressure reduction for some individuals.


Moon To Pass By Jupiter Tonight
It's been a busy week for stargazers. There was the asteroid flyby, the meteor collision, that mysterious light over California and tonight they'll be able to watch the moon passing by Jupiter.
According to Universe Today, the moon has had several visual close encounters with Jupiter since Thanksgiving. Tonight the moon will be passing in front of Jupiter.
The event is called an occultation, which simply means that one celestial body will move in front of another. Unfortunately, people in North America won't be able to see the occultation tonight.
Space.com reports that the moon will be below the horizon when it passes by Jupiter. Observers in North America will be able to see the moon approach Jupiter tonight, and on Monday, they'll be able to watch as the moon moves away from the planet.
Space.com writes:
"At mid-twilight, roughly 45 minutes after sunset, look high in the south, more than two-thirds of the way up from the horizon to the point directly overhead (the zenith) and — weather permitting — you'll see the moon and hovering about 6 degrees above and to its left will be brilliant Jupiter."
Here's a video of the moon passing by Jupiter on Christmas day, 2012.


text:
"California Water Plan Could Help Puget Sound Orcas Survive"
"A plan to restore salmon runs on California's Sacramento River could help revive killer whale populations 700 miles to the north in Puget Sound, as federal scientists struggle to protect endangered species in a complex ecosystem that stretches along the Pacific coast from California to Alaska.
Without wild salmon from the Sacramento and American rivers as part of their diet, the killer whales might face extinction. That's what scientists concluded in a biological opinion that could result in even more severe water restrictions for farmers in the drought-stricken, 400-mile long Central Valley of California. The valley is the nation's most productive farm region.
The plan has faced heated criticism from agricultural interests and politicians in California, but environmentalists said it represented a welcome departure by the Obama administration from its predecessor in dealing with Endangered Species Act issues."
Les Blumenthal reports for the Bellingham Herald July 5, 2009.


Delivered At Frontier - DAF
DEFINITION of 'Delivered At Frontier - DAF'
In international trade, a contract specification requiring the seller to deliver goods to a named destination, usually a border location, by a predetermined time. Up to the border, the seller is responsible for all risks and expenses associated with the delivery.
Terms used in international trade, such as delivered at frontier, outline who bears the risks and expenses of transporting goods under international transactions. A variety of terms exist for various methods of transportation. Delivered at frontier is most often used when using ground transport, such as truck or rail, to supply the goods.
 1. Acceptance Market
 2. Cost, Insurance and Freight - CIF
 3. Incoterms
 Trade terms published by the International Chamber of Commerce...
 4. Delivered Ex Ship - DES
 A trade term requiring the seller to deliver goods to a buyer...
 5. Welfare Capitalism
 Definition of welfare capitalism.
 6. LIBOR
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 1. What Is International Trade?
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Hot Definitions
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Trading Center


text:
The Arduino Leonardo is a microcontroller board based on the ATmega32u4 (datasheet). It has 20 digital input/output pins (of which 7 can be used as PWM outputs and 12 as analog inputs), a 16 MHz crystal oscillator, a micro USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started.
The Leonardo differs from all preceding boards in that the ATmega32u4 has built-in USB communication, eliminating the need for a secondary processor. This allows the Leonardo to appear to a connected computer as a mouse and keyboard, in addition to a virtual (CDC) serial / COM port. It also has other implications for the behavior of the board; these are detailed on the getting started page.
Note: This Arduino Leonardo comes with pre-soldered headers and 2.1mm power connector.
|Input Voltage (recommended)||7-12V|
|Input Voltage (limits)||6-20V|
|Digital I/O Pins||20|
|Analog Input Channels||12|
|DC Current per I/O Pin||40 mA|
|DC Current for 3.3V Pin||50 mA|
|Flash Memory||32 KB (ATmega32u4) of which 4 KB used by bootloader|
|SRAM||2.5 KB (ATmega32u4)|
|EEPROM||1 KB (ATmega32u4)|
|Clock Speed||16 MHz|
Schematic & Reference Design
EAGLE files: arduino-leonardo-reference-design.zip
The Arduino Leonardo can be powered via the micro USB connection or with an external power supply. The power source is selected automatically.
External (non-USB) power can come either from an AC-to-DC adapter (wall-wart) or battery. The adapter can be connected by plugging a 2.1mm center-positive plug into the board's power jack. Leads from a battery can be inserted in the Gnd and Vin pin headers of the POWER connector.
The board can operate on an external supply of 6 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may be unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts.
The power pins are as follows:
- VIN. The input voltage to the Arduino board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power source). You can supply voltage through this pin, or, if supplying voltage via the power jack, access it through this pin.
- 5V. The regulated power supply used to power the microcontroller and other components on the board. This can come either from VIN via an on-board regulator, or be supplied by USB or another regulated 5V supply.
- 3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA.
- GND. Ground pins.
- IOREF. The voltage at which the i/o pins of the board are operating (i.e. VCC for the board). This is 5V on the Leonardo.
The ATmega32u4 has 32 KB (with 4 KB used for the bootloader). It also has 2.5 KB of SRAM and 1 KB of EEPROM (which can be read and written with the EEPROM library).
Input and Output
Each of the 20 digital i/o pins on the Uno can be used as an input or output, using pinMode(), digitalWrite(), and digitalRead() functions. They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In addition, some pins have specialized functions:
- Serial: 0 (RX) and 1 (TX). Used to receive (RX) and transmit (TX) TTL serial data using the ATmega32U4 hardware serial capability. Note that on the Leonardo, the Serial class refers to USB (CDC) communication; for TTL serial on pins 0 and 1, use the Serial1 class.
- TWI: 2 (SDA) and 3 (SCL). Support TWI communication using the Wire library.
- External Interrupts: 2 and 3. These pins can be configured to trigger an interrupt on a low value, a rising or falling edge, or a change in value. See the attachInterrupt() function for details.
- PWM: 3, 5, 6, 9, 10, 11, and 13. Provide 8-bit PWM output with the analogWrite() function.
- SPI: on the ICSP header. These pins support SPI communication using the SPI library. Note that the SPI pins are not connected to any of the digital I/O pins as they are on the Uno, They are only available on the ICSP connector. This means that if you have a shield that uses SPI, but does NOT have a 6-pin ICSP connector that connects to the Leonardo's 6-pin ICSP header, the shield will not work.
- LED: 13. There is a built-in LED connected to digital pin 13. When the pin is HIGH value, the LED is on, when the pin is LOW, it's off.
- Analog Inputs: A0-A5, A6 - A11 (on digital pins 4, 6, 8, 9, 10, and 12). The Leonardo has 12 analog inputs, labeled A0 through A11, all of which can also be used as digital i/o. Pins A0-A5 appear in the same locations as on the Uno; inputs A6-A11 are on digital i/o pins 4, 6, 8, 9, 10, and 12 respectively. Each analog input provide 10 bits of resolution (i.e. 1024 different values). By default the analog inputs measure from ground to 5 volts, though is it possible to change the upper end of their range using the AREF pin and the analogReference() function.
There are a couple of other pins on the board:
- AREF. Reference voltage for the analog inputs. Used with analogReference().
- Reset. Bring this line LOW to reset the microcontroller. Typically used to add a reset button to shields which block the one on the board.
See also the mapping between Arduino pins and ATmega32u4 ports.
The Leonardo has a number of facilities for communicating with a computer, another Arduino, or other microcontrollers. The ATmega32U4 provides UART TTL (5V) serial communication, which is available on digital pins 0 (RX) and 1 (TX). The 32U4 also allows for serial (CDC) communication over USB and appears as a virtual com port to software on the computer. The chip also acts as a full speed USB 2.0 device, using standard USB COM drivers. On Windows, a.inf file is required. The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the Arduino board. The RX and TX LEDs on the board will flash when data is being transmitted via the USB connection to the computer (but not for serial communication on pins 0 and 1).
A SoftwareSerial library allows for serial communication on any of the Leonardo's digital pins.
The ATmega32U4 also supports I2C (TWI) and SPI communication. The Arduino software includes a Wire library to simplify use of the I2C bus; see the documentation for details. For SPI communication, use the SPI library.
The Leonardo appears as a generic keyboard and mouse, and can be programmed to control these input devices using the Keyboard and Mouse classes.
The Leonardo can be programmed with the Arduino software (download). Select "Arduino Leonardo from the Tools > Board menu (according to the microcontroller on your board). For details, see the reference and tutorials.
The ATmega32U4 on the Arduino Leonardo comes preburned with a bootloader that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the AVR109 protocol.
You can also bypass the bootloader and program the microcontroller through the ICSP (In-Circuit Serial Programming) header; see these instructions for details.
Automatic (Software) Reset and Bootloader Initiation
Rather than requiring a physical press of the reset button before an upload, the Leonardo is designed in a way that allows it to be reset by software running on a connected computer. The reset is triggered when the Leonardo's virtual (CDC) serial / COM port is opened at 1200 baud and then closed. When this happens, the processor will reset, breaking the USB connection to the computer (meaning that the virtual serial / COM port will disappear). After the processor resets, the bootloader starts, remaining active for about 8 seconds. The bootloader can also be initiated by pressing the reset button on the Leonardo. Note that when the board first powers up, it will jump straight to the user sketch, if present, rather than initiating the bootloader.
Because of the way the Leonardo handles reset it's best to let the Arduino software try to initiate the reset before uploading, especially if you are in the habit of pressing the reset button before uploading on other boards. If the software can't reset the board you can always start the bootloader by pressing the reset button on the board.
USB


Question from munaz_rahman
What are zone points for?
What are zone points for and what do they do?
Accepted Answer
BadProfessional answered:
Zone points increase your In The Zone multiplier, which makes the speed breaker more effective as well as increasing it's duration. They also add to the Wheelman points when you win a race, increasing your wheelman level.
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Let $V$ be a geometrically irreducible and reduced scheme defined over the real numbers, and let $K = K(V)$ be its function field.
 1. If $V$ does not have any real points, is it true that $K$ is not formally real? It seems this is a theorem due to (E.) Artin but I cannot find a modern reference and my German needs a little work.
 2. If $V$ does have real points, is $K$ necessarily formally real?
Thanks for the help.
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1 Answer 1
up vote 6 down vote accepted
The theorem you want is due to Serge Lang, from the following paper:
The theory of real places. Ann. of Math. (2) 57, (1953). 378–391.
The statement is almost, but not quite, what you suggest. To see the problem, a good example to consider is the affine plane curve over $\mathbb{R}$ defined by $\mathbb{R}[x,y]/(y^2+x^2+x^4)$. This defines a geometrically integral curve over $\mathbb{R}$ with non-formally real fraction field but possessing an $\mathbb{R}$-point, namely $(0,0)$. The key is that $(0,0)$ is the only $\mathbb{R}$-point on this curve and (thus!) it is a singular point.
So the correct result is that the function field of an integral affine variety $V_{/\mathbb{R}}$ is formally real iff $V$ admits a nonsingular $\mathbb{R}$-point. (Note that projective real algebraic varieties are also affine(!!).) Probably you could extend this to finite-type integral schemes without any trouble.
I also looked in Bochnak, Coste and Roy, following Thierry Zell's suggestion, but only found "half" of this result, namely the Artin-Lang Homomorphism Theorem. It seems likely though that I just didn't look hard enough: perhaps someone can enlighten me.
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Dear Pete, can you clarify what you mean by projective varieties over $\mathbf{R}$ being affine? The projective line over $\mathbf{R}$ is a counter-example if you take the usual, scheme-theoretic interpretations of these terms. – JBorger Nov 30 '10 at 12:05
See Chapter 3 of Bochnak, Coste and Roy for more details, but briefly: one has the notion of a real algebraic variety, a locally ringed space locally isomorphic to the set of $\mathbb{R}$-points of an affine $\mathbb{R}$-variety with the analytic topology. Of course projective space $\mathbb{P}^n$ is a real algebraic variety. But as a real algebraic variety, it is affine. – Pete L. Clark Nov 30 '10 at 13:00
For instance $\mathbb{P}^1$ is, as a real algebraic variety, isomorphic to $S^1= \operatorname{Spec}(\mathbb{R}[x,y]/(x^2+y^2−1))$. – Pete L. Clark Nov 30 '10 at 13:04
Thanks. So, by "real algebraic variety" you don't mean an algebraic variety (in any of the standard scheme-theoretic senses) over the field of real numbers. Dangerous terminology! – JBorger Dec 2 '10 at 9:04
_USER_: Yes, absolutely. In retrospect, I could have written this in a less confusing way. I find this quirk of real algebraic geometry amusing, but it's certainly not necessary to mention it in this context: it's pretty clear that the result in question extends to non-affine varieties. – Pete L. Clark Dec 2 '10 at 10:29
Your Answer


an English message might be valid or invalid. Or there might be nothing to discover. You can arrange so that if you find something, the odds are it isn't chance.
If you do find something, the process doesn't tell you if it is unusual luck, great wisdom, a great lie, or something else.
Graham raises some points.
... it is absolutely correct to say that we have no evidence for miracles. The main issue is the "any physical cause" part. In all experiments, the biggest problem is isolating the many other potential physical causes from the one(s) you're investigating. Every experiment already has a repeatable source of "miracles", which is the rest of the world injecting noise which gets past your experiment design.
However science can take a position on "we know there are these things which would cause exactly this" or at least "we may not know the cause but we have repeatedly seen this happen occasionally". So science certainly can say that something is not a miracle, only a low-probability event. More than that, it must, because if you attribute anything at all, ever, to divine intervention then you destroy any possibility to investigate a physical source. And that is directly opposed to rational thinking. We have historical proof of why this is wrong.
Your problem there is confirmation bias. If you have a sufficiently large random sample (such as, hypothetically, the digits of pi), then any encoding you care to pick (maybe ASCII) will eventually find a string of digits which produce the message "I'm God and I'm a black woman. Fix the Sistine Chapel ceiling.". Just for an example. It's equally likely as the encoding producing "zadfafhtyuweljhbgjkfyfqemgeghrhdf", because that's how probability works. The risk for miracle hunting is that you find something because you're looking for something without knowing exactly what.
My point is that you have to say beforehand what message you're looking for. If you can't do that, then you can't calculate odds, because that would be asking "what's the probability of finding something I've already found?" to which the answer is "exactly 1, because you've already found it". But if you can predict it then by your definition it's not a miracle, so you'rea bit stuck there.
 - 5
 $\begingroup$ Just to say the situation with religion is more complex than I think you may be aware. Shallow or lazy forms of religious commitment are indeed uneasy with science and are intellectually substandard. But the kind of religious commitment that is more carefully thought-through, such as for example that of James Clerk Maxwell or other leading physicists, both understands, respects and celebrates the role of science. This kind of religious commitment relates to science somewhat as do qualities such as honesty, humility and curiosity: they are not science, but they motivate, support and enable it. $\endgroup$ – Andrew Steane Mar 29 at 12:42
 - 2
 $\begingroup$ _USER_: I think you may be reading more into mmesser314's answer than intended. The way I read it, they're merely saying that religion-based explanations of mental phenomena such as sensation, emotion and consciousness do not satisfy the standards expected of a scientific explanation (such as falsifiability and the ability to make testable predictions). Which is reasonable enough, as that's not what they're supposed to be in the first place. $\endgroup$ – Ilmari Karonen Mar 29 at 13:33
 - $\begingroup$ _USER_ thanks for this remark which is friendly to all parties. I see what you mean but I also hope my comment will be helpful anyway. $\endgroup$ – Andrew Steane Mar 29 at 13:55
 - $\begingroup$ _USER_ - I am not implying shallow or lazy. I meant nobody has any explanation of the mind that includes a detailed enough mechanism to make me think they understand how the mind works. Freud made the first attempt to understand the structure of the mind with ideas like id, ego, and superego. But that is no more successful than fluxes and humors were in explaining medicine, or phlogiston in explaining heat. Nobody has explained the mind from first causes. $\endgroup$ – mmesser314 Mar 29 at 15:13
 - $\begingroup$ _USER_ - Thank you. I should have been more explicit. $\endgroup$ – mmesser314 Mar 29 at 15:13
I feel like biology and physics are completely separate
For where biophysics is heading, and due to the distinction that is arising between "biophysics" and "physics of living systems", I think the idea that it goes physics $\to$ chemistry $\to$ biology is no longer the case (if it ever was). People are actually using biological systems to learn more about physics now. So these fields are actually deeply connected: many biological problems now require physics (either directly, or at least in application of its principles, techniques, concepts, etc.), and many biological systems can be/are used to learn about physics.
It is true we do not have a complete knowledge of the physics of living systems. But we still have ideas as to how they are connected and applied.
Onto the title:
While my answer has claimed a strong link between physics and biology, there are of course distinctions. The statement "laws and behaviors observed in biology" is very broad. In physics, we all know the same principles; undergraduate physics education is essentially, "here are all of the principles of physics", and then if you go further into research you are essentially learning what those principles do in the universe. But if, say, a particle physicist wanted to talk to a solid-state physicist, they could still assume knowledge of the same base ideas in order to further understand each other.
In biology, it is somewhat the opposite. The field of biology is so vast and covers so many systems that there isn't really a shared set of underlying principles all biologists use. Someone working in developmental biology in the fruit fly will not be able to use their principles to determine what is going on with a biologist who is studying the interactions of species within some ecosystem. Just look across the answers to this question: there are so many areas of biology to consider, and they each have their own principles.
So while at the surface one can take the easy way out and say, "well, everything in the universe has to ultimately follow physics", if we dig deeper then we really need to be careful about what we mean by "laws and behaviors observed in biology". I might argue that there isn't a well-defined set of biological principles to even start exploring this question. (Although attempts are being made, e.g. William Bialek's book Biophysics: Searching for Principles)
What would a physics explanation of the mating behaviour of a bowerbird would look like, and who it would be useful to?
Biology is, in principle, reducible to fundamental physics but even if you were to solve any meaningful biological question in those terms - which is way beyond current abilities - the answer would get would have the wrong framing and explain at the wrong level. The meaningful answer for the bowerbird's wonderful mating ritual is one grounded in evolutionary theory not one grounded in particle physics.
 - $\begingroup$ even if you were to solve any meaningful biological question in those terms - which is way beyond current abilities - the answer would get would have the wrong framing and explain at the wrong level. This is incorrect. Many biological problems have appropriately been solved using physics. $\endgroup$ – BioPhysicist Mar 29 at 14:33
 - $\begingroup$ _USER_: You clipped the relevant part from that quote "reducible to physics" that I intend that comment to refer to. It's certainly true that useful biological questions are answered by physics, but they're not reductive in their approach. Physics will tell you a great deal about nerve signalling if you consider membrane potentials, for example, but fully describing a membrane by reducing it to quantum mechanics is impossible. $\endgroup$ – Jack Aidley Mar 29 at 15:15
 - 1
 $\begingroup$ Quantum biology is a field that is starting to get some traction. But in any case I don't think the only way to reduce something to physics is to take it all the way to the quantum/particle level. Certainly physicists were doing physics before quantum mechanics was even thought of. But I suppose that is the go-to for many people: physics = either quantum physics or astrophysics $\endgroup$ – BioPhysicist Mar 29 at 15:21
 - $\begingroup$ _USER_: I don't think physics is either quantum physics or astrophysics, but I do interpret the term "reducible" as an end-point description at the lowest available level. It seems you don't? I have edited to specify "fundamental physics". $\endgroup$ – Jack Aidley Mar 30 at 11:47
Every biological system is comprised out of zillions of elementary particles. Each of these particles interacts with a fraction of the others. Every interaction can be accounted for with the help of elementary particle physics. So yes, every biological system can be accounted for in a physical way. You and I are huge collections of elementary particles having this conversation.
What physics, or chemistry, or biology (evolution conforming to the gospel according to "Sir" Richard Dawkins), nor psychology, or whatever


text:
April 30 – National Raisin Day
Posted on April 30, 2012
National Raisin Day
Five Food Finds about Raisins
- In 1873, a freak hot spell withered the grapes on the vine. One enterprising San Francisco grocer advertised these shriveled grapes as "Peruvian Delicacies" and the rest is history.
- It takes more than 4 tons of grapes to produce 1 ton of raisins.
- The finest raisins come from Malaga in Spain.
- Raisin – comes from the Latin racemus and means "a cluster of grapes or berries".
- Fresno, California is the Raisin Capital of the World.
Today's Food History
on this day in…
1792 John Montague, 4th Earl of Sandwich died. Captain Cook named the Sandwich Islands after him (now known as Hawaii). He is supposed to have invented the sandwich as a quick meal so as not to interrupt his gambling sessions.
1904 The Louisiana Purchase Exposition opened in St. Louis (St. Louis World's Fair). It was at the Fair that the ice cream cone was supposed to have been invented. The hot dog and iced tea were also popularized at the Fair.
1952 Mr. Potato Head is introduced to the world. Mr. Potato Head is the also the first toy to be advertised on television.
1955 'Cherry Pink & Apple Blossom White' by Perez Prado hits number one on the charts.
1981 Dunkin Donuts opened its first store in the Philippines.


When a person is choosing a career path, an office job may not sound interesting, and can be boring to individuals who want more thrill out of life. There are many jobs that include more excitement than just sitting at a desk all day long.
Career Opportunities For Thrill Seekers
Here are a few career opportunities for people who seek thrill and adventure:
1. Firemen: Fanning The Flames Of Excitement
Firemen are often considered some of the bravest people around. They go to great lengths to keep people safe. Besides fighting fires, most firemen take an active part in the community. Most of these professionals are trained as paramedics as well. An individual who is interested in this career must be able to pass various physical and written tests. This person must be a high school graduate and over the age of 18. The hourly average salary of a fireman is approximately $20/hour. Being a fireman comes with many risks. Jumping into a burning building can harm personal health. However, saving someone else's life can be very rewarding.
2. Zookeeper: Wild Animals Galore
For people who love animals and crave excitement, it may be wise to consider a career as a zookeeper. This professional will need to have a college degree in environmental science or biology. The best training can take place on a volunteer basis or through an internship. A person will need to learn the habits of animals along with how to feed and care for these creatures. This type of job may be exciting, but salary tends to be on the low side. An average zookeeper's salary will range between $30,000 and $50,000 depending on experience. There are both risks and rewards associated with a job in wildlife management. It can be a great experience to help an endangered species live. However, wild animals can be very dangerous. Even if they seem calm, these creatures can be unpredictable. A zookeeper or anyone who cares for wild animals must be on guard at all times. There are numerous rules that must be followed carefully.
3. FBI: The Spies The Limit
Movies are always filled with exciting people who have the job as an FBI agent. Special agents normally work in areas involving kidnapping, extortion, foreign intelligence, and terrorism. A person in this field must be over 23 years old, possess a four-year degree, and have at least three years of practical experience. This job can get quite physical, so an individual must be in top shape. All candidates will train in Virginia at the Academy for FBI agents in Quantico. Salary for newcomers will be approximately $65,000 a year. Many people are interested in law enforcement. To get the most thrills in this field, a person should enter FBI training. This job is very dangerous, but can help to clean up the street with basis of this career standing for justice.
4. Rescue Team For The Coast Guard
The Coast Guard patrols the country's major waterways and deals with the protection of the environment. A candidate for a career as a Coast Guard Rescuer must be under 27 years old and have a high school diploma. A person must be in good physical shape with no legal violations. The excitement takes hold quickly because a person gets immediately emerged into missions. Dangers may lie around any corner. For example, it is not unusual to use a helicopter in a rescue or to battle rough water and difficult weather. There are many jobs that include a high amount of thrill and adventure. The above fields are just a sample to choose from. Through proper training and dedication, a person can work in a career that is both interesting and satisfying. Joshua Turner is a writer who creates informative articles relating to business. He aims to encourage further study with a Bachelor Degree in Fire Science. Enjoy this article? You've got time for another! Check out these related articles: Photo Credit: Shutterstock


text:
noise is random. According to this argument, if the VBW is 1Hz then we should NOT subtract the correction for 30Hz Resolution Bandwidth (RBW, see above on the calculation method), because this averaging procedure undertaken by the VBW process is already taking into account the correction; effectively the displayed value is already normalized to 1Hz if we use VBW = 1Hz.
2) A counter-argument says that what the display is actually showing at each lit pixel, is the noise power in the 30Hz resolution bandwidth. If you average the noise power over multiple readings, then the average of the noise power will improve (have less uncertainty) which will make the measurement of the noise power less noisy - but the average level itself will not be changed. So effectively: averaging decreases the noise on the noise power measurement, but doesn't affect the noise power measurement itself; then the correction factor for the 30Hz RBW Is still needed.
I wasn't entirely convinced and wanted to see for myself on the screen by actual observation, to prove it one way or the other. The measurements in the three photographs below are with the equipment unchanged, the ONLY change is the VBW setting which is changed from 1Hz (left) to 10Hz (middle) to 100Hz (right). If the former theory is correct (no correction required for the RBW because VBW already takes care of it), then changing from 1Hz VBW to 10Hz VBW will increase the level of the noise by 10dB (10 x log 10). A further increase of 10dB will apply when we increase the VBW from 10Hz to 100Hz.
To make this clear I have drawn a white line on each of the photos, to indicate where the argument (1) would expect the noise power measurement to be. The white box in the center is also drawn on by me, and indicates where the passband of the crystal filter lies. Here are the photographs:
What can clearly be seen is that as the VBW is changed from 1Hz to 10Hz and then 100Hz, the line becomes much more messy (noisy). But the LEVEL of the line remains completely unchanged. The center (average) of the "grass" height doesn't change. This supports entirely, the counter-argument (2) that the noise power measurement is not affected by the averaging inherent in the VBW selection; it only reduces the uncertainty, not the level. Therefore, the correction for the Resolution Bandwidth 30Hz to the normalized standard value 1Hz *IS* still required.
Kevin ZL1UJG also made a similar comparison and reached the same conclusion.
The work of OE3HKL _URL_ also uses 16x averaging and no adjustments are necessary for this in his phase noise calculation, indicating again the same conclusion.
Back to the concern over the crystal filter
Now compare the two images below.
On the right, this image is at 5kHz carrier separation. You can clearly see the noise power line slopes down from left to right. My interpretation of this is that the level of carrier leakage through the crystal filter, due to the stop-band attenuation of the crystal filter simply not being good enough, means that reciprocal mixing of the residual carrier leakage and the phase noise of the spectrum analyzer's own internal local oscillator, is raising the noise floor too much. It makes an accurate measurement close to the carrier impossible; but here even 5kHz away from the carrier is clearly not enough. The filter skirts are thereby suspected of not being sharp enough.
By contrast the second photo (left) shows 20kHz separation. There is a clear pedestal of phase noise at the crystal filter passband and the noise floor is really flat outside that; outside this, the noise floor is the noise floor of the spectrum analyzer. So the measurement can be trusted.
More crystal filters
Refer back up the page to the photo of the 9MHz crystal filters I had in the junkbox. There are 6, all the same size, but three of them had unidentified part numbers on them.
Therefore I made a sweep of each of the crystal filters on the spectrum analyzer, using the 5:16 transformers for matching the spectrum analyzer and tracking generator's 50-ohm ports to the filter's 500-ohm ports. The results are as follows (all frequencies measured in Hz):
|Part number||Center frequency||3dB Bandwidth||Purpose|
|XF-9A||8,999,690||2,350||SSB centered on 9MHz|
|XF-9D||8,999,570||4,460||AM centered on 9MHz|
|Z14-A1||8,998,040||2,400||Lower Sideband (LSB)|
|Z15-A1||9,001,435||2,730||Upper sideband (USB)|
It is evident that of the unknown crystal filters, one is intended for CW, one for LSB and one for USB (or vice versa depending how you look at it). I thought I should hit the carrier with the sharpest filtering possible and so I chose to further investigate the CW filter.
Now I used the QCX "Signal Generator" to generate a signal and sweep it through the filter slowly, recording one measurement at a time (amplitude on the spectrum analyzer screen) to plot the filter shape in a spreadsheet. This is the result:
Compare this to the trace obtained earlier (see above) for the ZF-9A (SSB) filter and you can see immediately that whereas the stop-band attenuation of the ZF-9A filter was around 60dB, this CW filter is much better, at least 90dB. A huge improvement in out-of-band attenuation as well as a narrower filter; this should allow both more accurate measurements as well as closer in measurements (smaller separation from the carrier).
Tests with the new filter
I removed the ZF-9A from my little PCB-boxed project containing the amplifier and filter; and replaced it with the Z13-A1 CW filter. Now admire the resulting trace below. The span is only 5kHz (a zoom in, compared to earlier sweeps above), and the carrier separation is only 1kHz. You can see the width of the noise pedestal is about 500Hz which corresponds to the observed width of the Z13-A1 CW filter. FINALLY this looks now, like the pictures in Kevin's document, with the attenuated peak offset to the side, and the phase noise pedestal coming through the crystal filter in the center. :-)
The CW filter is so narrow and its skirts are so steep, that even at 1kHz spacing, there is no interference from the limitations imposed by the spectrum analyzer's internal phase noise. In fact, I am able to measure even at 500Hz separation and still obtain accurate results.
Testing QCX Phase noise
Now comes a very large number of very tedious time-consuming measurements. For each measurement, I set the QCX signal generator to the desired frequency offset, assuming that 9,998,300 counts as Zero (this is the measured center frequency of this crystal filter). So for example, I set the signal generator to 9,997,800 to measure the 500Hz phase noise. Then I wait for a complete frequency sweep to fill up the display. Then move the cursor to the middle of the 500Hz filter passband, and try to take a measurement. There is some level of estimation involved because from one pixel to the next there is some uncertainty - the "grass" on the spectrum analyzer. I tried to estimate a level which is both at the center of the filter passband and also in the center of the noisy trace. Then recorded that in a spreadsheet and plotted it on a graph.
Measurements are taken at intervals:
- every 500Hz from from 500Hz to 2kHz
- every 2kHz from 2kHz to 10kHz
- every 10kHz from 10kHz to 100kHz
Seven different scenarios were investigated:
1. Standard QCX, with no modifications; a 4,700uF electrolytic capacitor is connected at the QCX power supply terminals
2. Adds a 10uF tantalum capacitor (low Equivalent Series Resistance ESR) at the supply pins of the Si5351A, i.e. parallel with capacitor C2
3. A 470uF electrolytic capacitor in parallel with C2 instead
4. A 300uH inductor in series with the Si5351A supply line, AND a 10uF tantalum capacitor
5. A 300uH inductor in series with the Si5351A supply line, and this time a 470uF capacitor across C2
6. A 300uH inductor and 470uF capacitor at the Si5351A supply (as 5), plus, a 10uF tantalum across the supply of IC4 the QSD FST3253
7. Unlike all of 1-6, this scenario is a standard unmodified QCX with 1m cable to the PSU and NO 4,700uF capacitor at the QCX power terminals
Here are the results:
What is very clear, is that there are no significant improvements available by playing with further cleaning the Si5351A supply: not a tantalum capacitor, not a large electrolytic, and not a series inductor as well or an additional capacitor at the FST3253 supply


Towson Homes
Towson, the county seat of Baltimore County, was first inhabited by Susquehannock Indians. Towson was founded in 1750 when two brothers, William and Thomas Towson, emigrated from Pennsylvania and started farming on Sater's Hill, to the northeast of York and Joppa Roads. In 1768 Thomas' son, Ezekiel built a large tavern at the crossroads, just north of where the Towson Theater is now located. A small village called "Towsontown" began to grow around it, serving area farmers who traveled on York, Dulaney Valley and Joppa Roads.


text:
BowlMade in Upper Salford Township, Montgomery County, Pennsylvania, United States, North and Central America
Attributed to John Nice, American, died 1906
Red earthenware with slip decoration and lead glaze
1895-74Gift of Edwin Atlee Barber, 1895
This bowl was made from high-quality clay found under the wet topsoil of Pennsylvania's low-lying plains. Southeastern Pennsylvania's terrain could support farms on the topsoil and potteries on the subsoil, so by 1810 potteries could be found in almost every township in Buck's County.
The work of the potter fit into the agricultural calendar. The clay was dug in the fall: topsoil was cleared and a foot-deep layer of clay was sliced and shoveled into a wagon, hauled to the pottery, and stacked. Before freezing weather, the clay was carried in baskets and dumped into a mill - a round tub with a revolving post set with blades. A horse harnessed to a sweep walked slowly around the tub, turning the blades. Water was flushed through to clean the clay and the resulting mass of plastic earth turned gray to yellow. The clay was then shaped into one hundred pound blocks and stored in a cellar where it was kept moist but would not freeze.
This bowl started out as a flattened ball of clay. The fragile form was shaped by the potter on his wheel, which was rotated at variable speeds by the potter pushing a foot wheel, which in turn was connected to a balance wheel, allowing for smooth and continuous rotation.
The interior is decorated with white slip in a petal-like pattern, which was applied when the ware was damp, and the green accents are copper oxide daubed on before glazing. The entire bowl is covered with a thick clear lead glaze, excluding the foot, which is unglazed.
* Works in the collection are moved off view for many different reasons. Although gallery locations on the website are updated regularly, there is no guarantee that this object will be on display on the day of your visit.


A useful tool for board self assessments
What happens at your organisation when you need a new board member? Maybe the conversation goes something like this:
"How about John? He is very credible and knows a lot about our sector."
"Yeah maybe, but do we need another older white guy? How about Marama? She's a dynamic young wahine who would bring some valuable new perspectives."
"Yes, she'd be good – except I don't think she has much governance experience does she? How about considering Marilyn…"
And so the conversation goes, until eventually, often simply by deferring to whoever has the strongest opinion, the board agrees who they will shoulder tap for the vacant position.
This approach of simply brainstorming names of people already known to board members is not the best way of building an effective governance team, but it seems to be surprisingly common. And what is actually happening in situations like the one above is that board members are really having two conversations simultaneously – one about whom to consider, and the other about which characteristics are most important. In this case, different board members are putting value on credibility, sector knowledge, diversity, new perspectives and governance experience – all of which are valid considerations. But, because the conversation jumps straight into debating the comparative merits of specific people, there is no opportunity to build consensus about which characteristics matter most and what is currently missing.
A better way of going about this is to start by explicitly identifying the gaps on the current board and prioritising these before going through a process to find the best-fit person.
How? Here is a Governance Self-Assessment worksheet which I have developed over the last few years which can be adapted for assessing where a board is at currently and what might be missing.
You are welcome to use and adapt this as you see fit, and acknowledgement of the source and sharing any improvements you make would be much appreciated.
Here's how to use this worksheet:
 1. As a board, decide which overall skills, experience, behaviours and diversity you want your board to have. The worksheet is pre-populated with suggestions in each category, and these are probably a reasonable start for most boards in Aotearoa NZ, particularly in the non-profit sector. Adapt and add to these as appropriate, and decide whether each criterion is "Essential" or "Desirable."
 2. Ask each board member and your CE / manager to fill out the worksheet. This involves each person assessing themselves against each criterion and also providing their assessment on how the overall board rates on each.
 3. Collate the results. This can be done by the Chair or a board member, or it can be done confidentially through an external consultant.
 4. As a board, review the collated results. What are the key gaps in governance skills and experience? What are some of the common themes in how board members think governance can be improved? From this, what are the key characteristics you are looking for in your new board member, and which ones are top priority? (Again this conversation can be done internally, but sometimes it is useful to use someone independent, and consultants like me and others with good governance and facilitation experience can be useful for guiding this process.)
 5. Now that you have an agreed list of what you are looking for, you can decide whether to go through a formal recruitment process where the role is externally advertised, or whether you prefer a more informal process. Best results usually come from spreading the net wide! (There are more suggestions which are particularly designed for philanthropic governance about possible ways to find and recruit best-fit trustees in my paper "Four steps to good practice family foundation governance", published in 2018.)
A good board is essential to an effective and impactful organisation, so ensuring that you have the best-fit people on your board is important. I hope this tool is helpful and I welcome your feedback.
Leave a Reply


text:
Common Information Model (CIM)
A set of preconfigured data models that you can apply to your data at search time. Each data model in the CIM consists of a set of field names and tags that define the least common denominator of a domain of interest. The CIM lets you normalize your data to match a common standard, using the same field names and event tags for equivalent events from different sources or vendors.
For more information
Download the Common Information Model add-on from Splunkbase:


Home >Rituals >
Atone Ritual 4
Uncommon Abjuration
Cast 1 day; Cost rare incense and offerings worth a total value of 20 gp × the target's level; Secondary Casters 1, must be the ritual's target
Primary Check Nature or Religion (expert); Secondary Checks Nature or Religion (whichever is used for the primary check)
Range 10 feet; Targets another creature of up to 8th level who is a worshiper of the same deity or philosophy as you
You attempt to help a truly penitent creature atone for its misdeeds, typically actions contrary to your deity's alignment or anathema to your deity. If the creature isn't truly penitent, the outcome is always a critical failure. This ritual uses Nature if the target is a druid, and Religion in all other cases.
 - Critical Success The creature receives absolution for its misdeeds, allowing it to regain standing with your deity. It returns to its previous alignment (if its alignment shifted) and regains any abilities it lost. Before the atonement is complete, the creature must perform a special quest or other task chosen by your deity, as befits its misdeeds. If completed during downtime, this task should take no less than 1 month. For 1 month, the target receives divine insight just before performing an act that would be anathema to your deity or contrary to your deity's alignment.
 - Success As critical success, but the creature gains no special insight regarding its subsequent actions.
 - Failure The creature does not receive absolution and must continue to meditate and redress its misdeeds. Any future atone rituals for the same misdeeds cost half as much and gain a +4 circumstance bonus to primary and secondary checks.
 - Critical Failure The creature offends your deity and is permanently cast out from the faith. The creature can't rejoin your religion without a more direct intervention.
Heightened (5th) Increase the maximum target level by 2 and the base cost by 20 gp.
Section 15: Copyright Notice


Appalachian mixed mesophytic forests
From Wikipedia, the free encyclopedia
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Appalachian mixed mesophytic forests
Hansons Point.JPG
Hanson's Point in the Red River Gorge, Kentucky
Appalachian mixed mesophytic forests map.svg
Biome Temperate broadleaf and mixed forest
Bird species 200[1]
Mammal species 73[1]
Area 192,200 km2 (74,200 sq mi)
Country United States
Habitat loss 14.8%[1]
Protected 8.37%[1]
The Appalachian mixed mesophytic forests is an ecoregion of the Temperate broadleaf and mixed forests Biome, as defined by the World Wildlife Fund. It consists of mesophytic plants west of the Appalachian Mountains in the Southeastern United States.
This ecoregion consists of the following EPA level III ecoregions:
This ecoregion is located in the plains and hill country west of the Appalachians in northwest Alabama and east central Tennessee, eastern Kentucky, western North Carolina and Virginia, most of West Virginia, western Maryland, southeastern Ohio and western Pennsylvania. These forests are known for their rich diversity of plants and animals, which is due to several contributing factors, especially that the area was an unglaciated refugia for many species. It shares species with the high elevation Appalachian-Blue Ridge forests to the east, the hardwood forests to the west, and the mixed hardwood/conifer forests to the south.
The climate varies from humid continental in the north to humid subtropical in the south.
They are one of the most biologically diverse temperate forest regions on earth. It has an unusually diverse tree flora, with as many as 30 tree species at a single site including many relics of the ancient forest that once covered North America more widely. Along with the forest there is a rich undergowth of ferns, fungi, herbaceous plants, shrubs and small trees as well as areas of glade, heath, shale, peat bog and cranberry bog.
Mesophytic forests[edit]
Mesophytic forests are found on deep and enriched soils in sheltered topography such as coves and low-elevation slopes. They are often found near small streams. The herb layer is very rich and, in undisturbed areas, the trees can grow very large. Typical trees include sugar maple (Acer saccharum), beech (Fagus grandifolia), tuliptree (Liriodendron tulipifera), basswood (Tilia americana), northern red oak (Quercus rubra), cucumber tree (Magnolia acuminata), and black walnut (Juglans nigra). Other trees found here are eastern hemlock (Tsuga canadensis), white ash (Fraxinus americana), sweetgum (Liquidambar styraciflua), and yellow buckeye (Aesculus flava).[2]
Dry calcareous forests[edit]
The southern Ridge and Valley/Cumberland dry calcareous forests occur on dry to dry-mesic calcareous habitats on low escarpments of the Cumberland Plateau. They are often found on deep soils in a variety landscapes within their range. Trees are mainly oaks and hickories, with other species less abundant. Oaks include white oak (Quercus alba), northern red oak (Quercus rubra), post oak (Quercus stellata), chinkapin oak (Quercus muehlenbergii), and Shumard oak (Quercus shumardii). Hickories include shagbark hickory (Carya ovata). Other trees can be sugar maple (Acer saccharum), eastern red-cedar (Juniperus virginiana), or pines.[3]
Appalachian cove forests[edit]
Appalachian cove forests are found in sheltered concave slopes with a moist environment. Characteristic tree include yellow buckeye (Aesculus flava), sugar maple (Acer saccharum), white ash (Fraxinus americana), basswood (Tilia americana), tuliptree (Liriodendron tulipifera), Carolina silverbell (Halesia tetraptera), eastern hemlock (Tsuga canadensis), beech (Fagus grandifolia), cucumber tree (Magnolia acuminata), and Fraser magnolia (Magnolia fraseri).[4]
Dry-mesic oak forests[edit]
Dry-mesic oak forests cover large areas at lower and middle elevations on flat to gently rolling terrain. Mature stands have a variety of oak and hickory species adapted to dry-mesic conditions. Oaks include northern red oak (Quercus rubra), white oak (Quercus alba), black oak (Quercus velutina), and scarlet oak (Quercus coccinea); hickories include mockernut hickory (Carya tomentosa), shagbark hickory (Carya ovata), red hickory (Carya ovalis), and pignut hickory (Carya glabra). In addition, red maple (Acer rubrum), sweet birch (Betula lenta), and yellow birch (Betula alleghaniensis) are common; sugar maple (Acer saccharum) is occasional. In areas that have been recently disturbed, white pine (Pinus strobus), Virginia pine (Pinus virginiana), or tulip tree (Liriodendron tulipifera) can be abundant. Areas of impeded drainage sometimes harbor small wetlands, including non-forested seeps or forested wetlands with red maple (Acer rubrum), swamp white oak (Quercus bicolor), or black tupelo (Nyssa sylvatica).[5]
Dry oak forests and woodlands[edit]
The Allegheny-Cumberland dry oak forest and woodland forest system is found on acidic soils on the Allegheny and Cumberland plateaus, and ridges in the southern Ridge and Valley. The forests are typically dominated by white oak (Quercus alba), southern red oak (Quercus falcata), chestnut oak (Quercus prinus), scarlet oak (Quercus coccinea), with lesser amounts of red maple (Acer rubrum), pignut hickory (Carya glabra), and mockernut hickory (Carya tomentosa). A few shortleaf pines (Pinus echinata) or Virginia pines (Pinus virginiana) may occur, particularly adjacent to escarpments or following fire. Sprouts of chestnut (Castanea dentata) can often be found where it was formerly a common tree.[6]
Low-elevation pine forests[edit]
Southern Appalachian low-elevation pine forests occur on a variety of topographic and landscape positions, including ridgetops, upperand mid-slopes, and in lower elevations (generally below 2,300 feet (700 m)) such as mountain valleys. These forests dominated by shortleaf pine (Pinus echinata) and Virginia pine (Pinus virginiana).Pitch pine (Pinus rigida) may sometimes be present. Hardwoods are sometimes abundant, especially dry-site oaks such as southern red oak (Quercus falcata), chestnut oak (Quercus prinus), and scarlet oak (Quercus coccinea), but also pignut hickory (Carya glabra), red maple (Acer rubrum), and others. The shrub layer may be well-developed, with hillside blueberry (Vaccinium pallidum), black huckleberry (Gaylussacia baccata), or other acid-tolerant species most characteristic. Herbs are usually sparse but may include narrowleaf silkgrass (Pityopsis graminifolia) and Goat-rue (Tephrosia virginiana).[7]
Montane oak forests[edit]
Montane oak forests occur on exposed ridges and on southto west-facing slopes at middle elevations. Soils are thin and nutrient-poor and trees are often stunted and wind-flagged. Northern red oak (Quercus rubra) and white oak (Quercus alba) are common, as are sprouts of American chestnut (Castanea dentata). Winterberry (Ilex montana), flame azalea (Rhododendron calendulaceum), catawba rhododendron (Rhododendron catawbiense), and great rhododendron (Rhododendron maximum) are common shrubs.[8]
Hemlock-northern hardwood forests[edit]
Hemlock-northern hardwood forests are found at higher elevations. They include yellow birch (Betula alleghaniensis), mountain maple (Acer spicatum), sugar maple (Acer saccharum), beech (Fagus grandifolia), and eastern hemlock (Tsuga canadensis). Mountain laurel (Kalmia latifolia) and rhododendron (Rhododendron spp.) are found in the understory.[9]
Spruce-fir forests[edit]
Spruce-fir forests occur at the highest elevations, above 3,200 feet (980 m). Their environment is cool and wet, with frequent fog and precipitation. Red spruce (Picea rubens) and Fraser fir (Abies fraseri) dominate the forest canopy.[10]
C