text:
Klaus Hartmann (* 1954 in Koblenz) ist ein deutscher Philosoph und Anthroposoph.

Leben
Hartmann stammt aus Koblenz-Ehrenbreitstein. Er studierte Philosophie, Geschichte und Germanistik an der Ruhr-Universität Bochum und der Bergischen Universität-Gesamthochschule Wuppertal und wurde 1986 bei Wolfgang Janke im Fachbereich Philosophie an der Universität Wuppertal mit der Dissertation Die freiheitliche Sprachauffassung des Novalis zum Dr. phil. promoviert.

Er ist für den Novalis-Hochschulverein in Kamp-Lintfort, den er mitbegründete, die Herbert Witzenmann Stiftung in Pforzheim (als Herausgeber) und die Fachhochschule Ottersberg (als Dozent für Philosophie) tätig. Hartmann ist darüber hinaus seit 1998 Mitglied des Kollegiums des Arbeitszentrums NRW der Anthroposophischen Gesellschaft in Deutschland, seit 1988 Herausgeber von Werken aus dem Nachlass des Anthroposophen Herbert Witzenmann, den er durch Vermittlung von Lothar Udert in dessen erkenntniswissenschaftlichen Seminaren 1978 an der RUB kennenlernte und Dozent beim Begleitstudium für Anthroposophie, das sich auf die Grundwerke Rudolf Steiners stützt, am Herbert Witzenmann Zentrum in Dornach SO.

Schriften (Auswahl)
 Die freiheitliche Sprachauffassung des Novalis (= Abhandlungen zur Philosophie, Psychologie und Pädagogik. Band 208). Bouvier Verlag, Bonn 1987, ISBN 3-416-02014-6. [zugl. Diss., Univ. Wuppertal, 1986]
 Innere Motive im Lebensgang Rudolf Steiners. Verlag am Goetheanum, Dornach 2004, ISBN 3-7235-1204-6.
 Mit Helsen Durrer Greet: Beppe Assenza. Ein Leben für die Malerei und Anthroposophie. Zum malerischen Schulungsweg in den Skizzenbüchern.  Gideon Spicker Verlag, Dornach 2005, ISBN 3-85704-180-3.
 Herbert Witzenmann, 1905–1988. Eine Biographie. 2 Teile, Gideon Spicker Verlag, Dornach 2010/13.
 Teil 1: 1905–1961. 2010, ISBN 978-3-85704-198-3.
 Teil 2: 1962–1988. 2013, ISBN 978-3-85704-199-0.

Weblinks

Einzelnachweise

Anthroposoph
Philosoph (20. Jahrhundert)
Deutscher
Geboren 1954
Mann

redpajama_set_name: RedPajamaWikipedia


text:
Scottsdale Update - Aug. 22, 2022
Cactus Park is closed for monsoon storm cleanup. A handful of Indian Bend Wash crossings remain closed as well: Medlock Drive at Hayden Road, the Safeway parking lot entrance from Hayden Road, and the Chaparral, Camelback and Indian School tunnels along in the path. We will be updating information when it is available. Be monsoon ready.
Study identifies strategies for a cooler Scottsdale. Heat remains one of our region's top sustainability challenges, with far-reaching impacts on health, infrastructure, environment and economic well-being. In 2020, Scottsdale partnered with Arizona State University to assess patterns of urban heat in the city and identify promising cool strategies.
The study results (PDF) are outlined in a StoryMap, which explains the basics of heat impacts in Scottsdale, contains examples of areas with the hottest and coolest surface temperatures, and outlines strategies and goals for heat mitigation. As a part of a Tuesday, Sept. 13, work study session, the City Council will discuss developing the city's first Heat Mitigation Plan, based on the study's framework.
Please share your recommendation for achieving a cooler city on our new Heat Mitigation Plan webpage.
The Arizona Department of Environmental Quality has issued a high ozone pollution advisory through Wednesday, Aug. 24. Those with respiratory sensitivities are advised to take precautions during outdoor activities. Please help reduce ozone by doing one or more of the following:
Use gas or electric instead of burning wood
Limit the lighting of fireworks
Ride transit, carpool or telework
Eliminate all unnecessary driving and/or combine trips
Avoid dirt roads
Avoid the use of leaf blowers
If burning wood for heat or food preparation, use dry wood (burning wet wood releases more particulate matter)
Commemorate Women's Equality Day, Friday, Aug. 26. Women's Equality Day commemorates the 1920 adoption of the 19th Amendment to the United States Constitution, which prohibits states and the federal government from denying U. S. citizens the right to vote based on gender.
Scottsdale has a long history of strong female leadership. Four of six Charter Officers in Scottsdale are women (attorney, auditor, presiding judge and treasurer); as are five of seven City Council members (Tammy Caputi, Betty Janik, Kathy Littlefield, Linda Milhaven and Solange Whitehead). At a recently held Women's History Month panel discussion, each Councilwoman provided insight into who and what inspired them to take on influential roles, and how they are inspiring other women to do the same. Watch here.
Featured Job(s) of the Week: Maintenance Workers. The city has several openings for Maintenance Workers I and II. Job duties vary slightly depending on the location of the position. For example, you might be performing groundskeeping duties at Scottsdale Stadium, maintaining the equestrian facilities at WestWorld or taking care of the landscape and irrigation at Civic Center. Learn more about these positions and apply.
Get a head start learning about city issues, projects and activities by attending or listening in on the many public meetings we host. Here's what's coming up:
Scottsdale City Council – 5 p.m. Monday, Aug. 22 (PDF)
Scottsdale City Council Regular Meeting and Work Study Session – 5 p.m. Tuesday, Aug. 23 (PDF)
Industrial Development Authority – 8:30 a.m. Wednesday, Aug. 24
Planning Commission – 5 p.m. Wednesday, Aug. 24
Citizen's Bond Oversight Commission – 5 p.m. Thursday, Aug. 25
Learn about our various Boards and Commissions and how you can serve.
Find more public meetings.
Mustang Library hosts free film, "Uncharted." Street-smart Nathan Drake is recruited by seasoned treasure hunter Victor "Sully" Sullivan to recover a fortune amassed by Ferdinand Magellan lost 500 years ago by the House of Moncada. The show starts at 2 p.m. Wednesday, Aug. 24, at 10101 N. 90th St. Learn more.
"Disenchanted!" shines new light on beloved characters at Scottsdale Center for the Performing Arts. Audiences can join Snow White and her posse of disenchanted princesses in Aug. 25–28 at the Scottsdale Center for the Performing Arts. Using an all-woman cast, "Disenchanted!" introduces beloved princesses in brand-new roles, including Snow White as the self-assured leader of the princess pack; Cinderella as an enthusiastic feminist; Sleeping Beauty as the comedic opposite of Snow White; and many more familiar faces. Learn more and buy tickets.
Sister Cities hosts Art of Kenya – Encore Exhibit at Appaloosa Library, Aug. 29-Nov. 5. View the beautiful art of our sister city, Uasin Gishu, Kenya, at the library, 7377 E. Silverstone Drive. Learn more about the exhibit. You can also meet Kennedy Kibet, coordinator of the Kenyan Sister City program and this show. Kennedy is an artist with a passion to mentor and support local artists. The meet and greet is from 4-5:30 p.m. Thursday, Sept. 1, at the Scottsdale Artists School, 3720 N. Marshall Way. Learn more about the meet and greet.
Scottsdale ArtWalk: Internationally known as a mecca for art collectors, Scottsdale is home to more than 100 galleries, dedicated to exhibiting the finest visual art from around the world and locally. Stroll at your own pace. 7-9 p.m. Thursdays.
Get more events information.
Do you know someone who is interested in learning English as a second language? Experienced ESL instructors will help learners improve vocabulary, comprehension and word recognition. Participants attend in person from 5-7 p.m. Wednesdays for 12 weeks, Sept. 7-Nov. 16. Registration is required. Contact the center at 480-312-2529 for details.
"Meet and greet" provides networking and educational opportunities to transform your business. You're invited to this inaugural Scottsdale and HUUB small business event where you'll meet city department teams and others to help you with your business needs. The event runs from 9-10:30 a.m. Thursday, Sept. 15, at Scottsdale Stadium, 7408 E. Osborn Road. Registration required.
Youth Development connects family in need with crucial after-school care. The Scottsdale Unified School District contacted the city's Youth Development team about a struggling single mother who recently lost her job due to a lack of after-school care. Staff quickly worked to to enroll her children in the city's after-school program at Yavapai Elementary School. The local nonprofit Scottsdale Community Partners is covering the nearly $1,300 annual fee through a scholarship program. Human Services offers a variety of assistance programs; learn more.
Scottsdale Bobcats Special Olympics teams return for the fall season. After a pause in programming through COVID-19, Adaptive Services is ready to field athletes and teams to compete in bocce ball, golf, swim and bowling. The Scottsdale Bobcats are made up of athletes of all ages with intellectual disabilities. Scottsdale's delegation trains for 8 to 10 weeks, followed by area competitions against other East Valley teams in Special Olympics Arizona's Four Peaks division.
New Podsdale episode: Water Works. Scottsdale Water is hiring, and no experience is required! This week on Podsdale, Kevin Rose and Valerie Schneider give us the inside scoop on Scottsdale Water's trainee and apprenticeship programs. These full-time, paid positions, provide on-the-job training so you can start an exciting career in the water industry. "Water" you waiting for? Search "water careers." Listen now.
Watch Fast Five. The city's free Mediation program is back, the Scottsdale Airport received more than $5.4 million in FAA grants, and we celebrate the opening of Scottsdale's newest park. These are just a few of the things you need to know on this episode of Fast Five. Watch now.
The Government Finance Officers' Association recognized the city's 2021 Annual Comprehensive Financial Report with an Achievement of Excellence in Financial Reporting. This certificate is the highest form of recognition in governmental accounting and financial reporting, representing a significant accomplishment by a government and its management.
City Call Center – 480-312-3111
Report things that need to be fixed, or submit other requests via Scottsdale EZ
Traffic Restrictions Map – We update this map weekly to include most road improvement projects
Brush and Bulk Schedule
Scottsdale Weather

redpajama_set_name: RedPajamaCommonCrawl


text:
package com.ilves.electricityproject.fragments;

import android.os.Bundle;
import android.support.v4.app.ListFragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.ViewGroup;

import com.ilves.electricityproject.BusesAdapter;
import com.ilves.electricityproject.R;

public class BusesFragment extends ListFragment implements
		OnTouchListener {

	private ScaleGestureDetector	mScaleDetector;
	private float					mScaleFactor	= 1.f;
	BusesAdapter					adapter;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		mScaleDetector = new ScaleGestureDetector(getActivity(), new ScaleListener());
	}

	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container,
			Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		View v = inflater.inflate(R.layout.buses, container, false);
		// mSurface = (SurfaceView) v.findViewById(R.id.surface_view);
		adapter = new BusesAdapter(getActivity());
		setListAdapter(adapter);
		return v;// super.onCreateView(inflater, container, savedInstanceState);
	}

	@Override
	public boolean onTouch(View v, MotionEvent event) {
		Log.i("MainActivity", "onTouch");
		// Let the ScaleGestureDetector inspect all events.
		mScaleDetector.onTouchEvent(event);
		adapter.notifyDataSetChanged();
		return false;
	}

	private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {
		@Override
		public boolean onScale(ScaleGestureDetector detector) {
			mScaleFactor *= detector.getScaleFactor();

			// Don't let the object get too small or too large.
			mScaleFactor = Math.max(0.1f, Math.min(mScaleFactor, 5.0f));

			adapter.setScale(mScaleFactor);
			// invalidate();
			return true;
		}
	}

}

redpajama_set_name: RedPajamaGithub


text:
The Schwaltenweiher is a reservoir in the Ostallgäu foothills of the Alps in Bavaria, Germany. It lies  from the Allgäu Alps between the towns of Seeg and Rückholz. It was named after the Schwaltenmühle mill built beside it, which was in turn named after the Schwalt or Schwald family. It is now used for bathing and fishing.

History
Maximilian I, Holy Roman Emperor set aside the lake in 1514 for fishing and hunting waterfowl. His neighbouring Schloss Falkenberg (at what is now Goldhasen am Westufer) was destroyed by Imperial troops during the Thirty Years' War to prevent it falling into Swedish hands. The lake has passed through several owners over the following centuries, and is still in private hands. Notable guests there have been Theodor Heuss, Horst Köhler and Theo Waigel.

RSchwaltenweiher
Lakes of Bavaria
Reservoirs in Bavaria
Ponds of Germany


text:
Photo Credit: AfroTech
Careers in Tech: Ashton Elizabeth Talks Making the Leap into Tech from a Nontraditional Background
AfroTech. Apr 5, 2021.
You don't always need a traditional computer science background to make it in tech. Ashton Elizabeth is living proof of that.
The Seattle-based software engineer didn't take a straight path into the tech field but has now been at Indeed for the past three years. And she knows about navigating twists and turns in the career path.
Having originally gone to school to study psychology, Ashton's focus was working with children — particularly kids diagnosed with autism. From there, she worked in the nonprofit sector to develop after-school programs in low-income housing complexes. And while she remains passionate about working with kids, Ashton decided to challenge herself by jumping into something new: the for-profit sector.
"I wanted to stay competitive," says Ashton, "so I decided to add that technical toolbelt to my skill set." From there, she enrolled into a bootcamp where she trained to become a software engineer. Not long afterwards she found herself at Indeed. As part of her role, Ashton builds microservices for the Enterprise Billing Platform and leads the Seattle chapter of the Black Inclusion Group, which she co-chairs. It's a far shout from her nonprofit background but just as rewarding.
And while she works to maintain her outside passions and hobbies — working with children, dance and rock climbing — her ultimate goal as a Diversity, Inclusion & Belonging advocate is to inspire more individuals from underrepresented backgrounds to enter the tech field.
The key to making it all come together is practice. Whether the aim is learning a coding language or demonstrating a skill set during an interview, Ashton encourages job seekers to keep their skills sharp by practicing. "You don't have to be an expert in every single thing," she says. "Just as long as you get that top-level thing down."
Learn more about Ashton's career journey, and find out her advice for people looking to get a jump-start into a career in tech.
This editorial is brought to you in partnership with Indeed.


Fraunhofer's HE-AAC v2 audio codec enables true audio experiences for AUPEO! Internet radio listeners on the go or at home. Fraunhofer IIS, the world's authoritative source of audio and multimedia technologies, today announced it has been selected by AUPEO!, a leading provider of personalized audio streams for Internet-capable consumer devices, to license its high-quality HE-AAC v2 audio codec software.
Fraunhofer IIS, the leading innovator of technologies for cutting-edge audio and multimedia systems, today announced the worldwide launch of Diveemo®, the new small-scale video service for Digital Radio Mondiale (DRM) at IBC 2010. Initiated as a joint effort between Fraunhofer IIS, Thomson Broadcast & Multimedia and Chengdu NewStar Electronics, Diveemo delivers cost efficient large-area distribution of education and information video programs via DRM.
Fraunhofer's telepresence@home HD video conferencing technology, developed within the EU project "Together Anywhere Together Anytime" delivers a "sameroom" experience despite the distance between users.
For years the Center for Intelligent Objects ZIO has been combining research and development of cutting edge technologies and their successful commercial application to business practice. ZIO is presenting selected highlights of this work at booth A 21.


text:
Facebook secretly deleted messages Mark Zuckerberg sent on Messenger
Messages have vanished from recipient's inboxes
Apr 6, 2018, 7:50 AM UTC |
Illustration by James Bareham / The Verge
Facebook has admitted the company has been secretly deleting messages sent on Messenger by founder and CEO Mark Zuckerberg. "After Sony Pictures' emails were hacked in 2014 we made a number of changes to protect our executives' communications," says a Facebook spokesperson in a statement to TechCrunch. "These included limiting the retention period for Mark's messages in Messenger. We did so in full compliance with our legal obligations to preserve messages."
Old Facebook messages sent by Zuckerberg have simply vanished in some existing threads, and TechCrunch reports that affected messages no longer appear in Facebook's download your information tool. Recent messages from Zuckerberg reportedly remain in some users' inboxes, and the company doesn't appear to have cleared out all of Zuckerberg's older messages prior to 2014. Facebook has never publicly disclosed the removal of these messages until now, and simply quietly deleted them from recipient's Messenger inboxes. Regular Facebook users aren't able to delete their own messages from other people's Messenger inbox, and a special process was applied to Facebook executives.
Facebook's actions look shady even if they're not
Facebook's own terms of service don't cover the company removing content from accounts unless it violates community standards, so Facebook's actions look shady as a result. The actions could be viewed as an attempt to remove potentially embarrassing messages, and this is particularly relevant given the history of Facebook. Zuckerberg called people "dumb fucks" for trusting him early on at the beginning of Facebook, and he allegedly hacked into a Facebook user's private email account back in 2004.
Got a tip for us? Use SecureDrop or Signal to securely send messages and files to The Verge without revealing your identity.
This latest revelation comes at a time of increased scrutiny on Facebook's privacy policies and data protection. Facebook revealed earlier this week that as many as 87 million people, mainly in the US, had their data obtained by Cambridge Analytica. Facebook is implementing some broad platform changes to prevent this from happening in the future, and the company is looking for "suspicious activity" from developers to audit them fully after it made similar changes back in 2014 seemingly without an audit. Facebook CEO Mark Zuckerberg will now testify before Congress next week to answer questions about his company's use and protection of user data.
Zuckerberg also revealed this week that "malicious actors" have been scraping phone numbers and email addresses of Facebook accounts, and Facebook's chief technology officer told the Financial Times that the company has changed its approach to threats from hackers. "We will still be launching new products but prior to launching them we are sitting down and trying to think of all the possible bad uses of them and what bad actors might do with them, and how do we mitigate those things," says Facebook CTO Mike Schroepfer.
Facebook is also reducing its Android call history and SMS data collection, after some users were alarmed to discover years of phone records and SMS communications in their accounts. Facebook has been using what it calls an "opt-in feature" to improve its friend recommendation algorithm by requesting access to contacts, SMS data, and call history on Android phones. Facebook is now reducing the amount of data it collects, and deleting old call logs.
BP makes an order for EV charging stations from US-based Tritium
Samsung Display shows off a new folding phone hinge that can rotate 360 degrees


The placenta has numerous functions that serve to optimize the uterine environment for conceptus growth and development. The placenta is the primary site of physiological exchange between the conceptus and parent. Exchanges include transfer of oxygen and nutrients or other substrates from the maternal blood to the conceptus, as well as transfer of carbon dioxide, and other waste products from the fetus to the parent. The placenta acts as an endocrine, autocrine, and paracrine organ. It synthesizes a large variety of hormones and other substances that are released to the maternal as well as fetal circulations. It protects the conceptus from the maternal system. The objective of this article is to summarize the major functions of the placenta and some of the mechanisms involved in performing those functions.


Kill Ugly Radio | Frank Zappa & Elsewhere » Silencio!
Anyone seen David Lynch's Mulholland Drive? I have a couple of days ago, and now I'm needing to peruse this site in order to get what the hell it was all about.
You should see the 1966 movie Persona from Ingmar Bergman, Lynch was inspired in that movie and it should help you understand a bit of what happened, also, try to look at it in a non linear kind of way, and then get the events together like a puzzle, it is not that hard and it feels great when you finally understand it whitout any help from a website.
This movie is a masterpiece. It has to be seen at least 2 times in a week the first time you see it for the first time.
You are reading Silencio! which was posted on Tuesday, July 6th, 2004 at 10:06 am by Barry's Imaginary Publisher. This entry is filed under Film, Personal, Uncategorized.


text:
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Texas Woman's University
An act of the 27th Texas Legislature in 1901 founded the Girls Industrial College as a public institution that would become Texas Woman's University in 1957. The school had then and has now a dual mission: to provide a liberal education and to prepare young women "for the practical industries of the age" with a specialized education. TWU continues today as a public university that offers a comprehensive catalog of academic studies, including baccalaureate, master's and doctoral degrees. The university has grown from a small college to a major university. TWU is the largest university primarily for women in the United States, with the main campus in Denton and health science centers in Dallas and Houston.
Texas Woman's University builds on its long tradition as a public institution primarily for women by educating a diverse community of students to lead personally and professionally fulfilling lives. TWU prepares women and men for leadership and service through high quality undergraduate, graduate and professional programs on campus and at a distance. A TWU education ignites potential, purpose and a pioneering spirit.
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Brescia College
Brescia was founded in 1919 by the Ursuline Sisters, strong women of faith who are committed to social justice, community service, and the development of women.
Brescia University College, Canada's only women's university, is affiliated with Western University, the third-largest university in Ontario. Because of this, students benefit from the small, supportive atmosphere at Brescia while still enjoying the resources Western has to offer.
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St. Catherine University, or St. Kate's as it's commonly known, was founded in 1905. Grounded in the liberal arts and the Catholic traditions of intellectual inquiry and social teaching, St. Kate's educates women to lead and influence. St. Kate's offers associate, bachelor and advanced degree programs in four schools: the School of Business and Professional Studies; the School of Humanities, Arts and Sciences; the Henrietta Schmoll School of Health; and the School of Social Work. With more than 60 programs of study, the College for Women is among the largest private women's colleges in the nation. The University also offers a range of programs for women and men in the Graduate College and College for Adults. At every degree level, St. Kate's serves a diverse student population; developing ethical, reflective and socially responsible leaders. St. Kate's president is ReBecca Koenig Roloff, a 1976 graduate of the University.
St. Catherine University educates students to lead and influence. St. Catherine integrates liberal arts and professional education within the Catholic tradition, emphasizing intellectual inquiry and social teaching, and challenging students to transformational leadership.
http://www.stkate.edu
Cross Country/Track and Field
admission@stkate.edu
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When Bryn Mawr College opened its doors in 1885, it offered women a more ambitious academic program than any previously available to them in the United States. Other women's colleges existed, but Bryn Mawr was the first to offer graduate education through the Ph.D.—a signal of its founders' refusal to accept the limitations imposed on women's intellectual achievement at other institutions.
A Bryn Mawr woman is defined by a rare combination of personal characteristics, which include an intense intellectual commitment, a purposeful vision of her life and a desire to make a meaningful contribution to the world. These attributes create a spirit that is palpable on campus.
http://www.brynmawr.edu
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My flesh and my heart faileth: but God is the strength of my heart, and my portion for ever. For, lo, they that are far from thee shall perish: thou hast destroyed all them that go a whoring from thee. But it is good for me to draw near to God: I have put my trust in the Lord GOD, that I may declare all thy works.
Asaph learns by the end of this psalm that it is worth it to pursue a godly life. It is not vain, as he had felt before, but it is a good thing, perhaps the best choice he will make. Asaph realizes that he will have these moments of weakness. He is a man in the flesh living in a sinful world, but God is with Him. He can never lose that most precious and valuable treasure. God will strengthen him and uplift him out of those sorrows, misunderstandings, and weak moments.
Drawing near to God is the best place we can find ourselves, and all of that other stuff, like success and wealth and worldly prosperity, loses its appeal. We'll find that our desire is instead for a God-centered life, to know Him better and be drawn closer to Him. It is a passion and a fervency for only Him, and we find in Him, instead of the world, our fulfillment and satisfaction. As we continue a pursuit of God, we won't ever feel like we are missing out.
Asaph's dilemma in this psalm was that the wicked seemed to be prospering while he, a man seeking God and seeking righteousness, was not. But those who seem to prosper now but leave God out of their lives are not to be envied, because they face a fate no one would ever wish for. The best thing to do is exactly what Asaph did—to draw near to God, to continuously seek Him and follow Him and trust Him with our whole lives. We won't regret that when our end comes.
The truth is that we can trust God. We can trust Him with the whole of our lives. And we can get as close as possible to Him. And how amazing is that? Because all that energy and time and effort we might spend pursuing those things of the world that will only leave us empty can be spent pursuing an infinite and eternal God with no beginning, no ending, a God of love and mercy and grace who will fill our lives to overflowing. May we not be envious of the wicked world around us, but instead jealously guard our relationship with the Lord.
This entry was posted in devotionals and tagged bible, christianity, God, relationship, trust. Bookmark the permalink.


We winter in Mexico and have driven that route for over 25 years. Normally we go from Tucson to Albuquerque to Denver, Omaha and Fargo. But this week I see that I-80 near Omaha is flooded. I looked at a few alternates and they too had long detours. I am considering going from Albuquerque to Tucumcari, then 54 to Salina and then 81 to I-90 and east on I- 90 to Sioux Falls. Any thoughts on that route? We will be leaving Tucson this coming weekend. All help appreciated.
As of March 15, I-80 is open in both directions.
Thanks but I think that the ramp to I-29 is closed as well as part of I_29. I don't know if the Bridge is open.
Checked Missouri DOT website and I-29 was closed at the Iowa border as well as most of it thru iowa, they recommend taking I-35.
I had read that ! 29 had closures. But my route takes me from Salina,ks to Mitchell via 81 and then 90 to Sioux falls. So far that route is safe!
We just travelled back from Denver to Sioux Falls. I76 - I80 - I29. The only detour was when we went around Omaha on I680, we had to detour north on US75 to Blair, NE, then take US30 back east to I29 which really doesn't add a whole lot of time.


text:
\section{Introduction}
In a system of correlated electrons the external magnetic field can
induce several interesting effects. Theoretically the least understood
are those phenomena, where the magnetic field couples to the motion of
charge carriers. In recent years it has been realized that the
understanding of the anomalous temperature- and doping-dependence of
the Hall effect \cite{ong} is one of the most challenging questions in
connection with the normal state of cuprates, being representatives of
two-dimensional (2D) doped magnetic insulators. Here even the sign of
the effect is theoretically controversal \cite{brin1,assa}. The
diamagnetic contribution to the d.c.\ susceptibility has been much
less investigated \cite{wals}, although it is closely related to the
Hall conductivity \cite{rojo}. It emerges from the orbital motion of
mobile carriers. For noninteracting electrons the contribution
corresponds to the Landau diamagnetism, which is largely temperature
independent. In analogy to the Hall effect and other anomalous
properties of the normal state in cuprates, one could expect anomalies
also in the diamagnetic contribution. So far, however, both
experimental and theoretical answers are lacking.

Magnetic field dependence of the eigenstates of tightbinding electrons
is nontrivial even in the absence of any electron correlations
\cite{hofs}, in particular when the dependence of the ground state on
the field strength $B$ and electron density is investigated
\cite{hase,nori}. There have been only few analogous studies of
correlated systems. Recently, the ground state of a single hole in the
2D $t$-$J$ model in the presence of magnetic field \cite{bera} has
been studied. The main message is that for finite (but not very small)
$B$ the energy is reduced by an amount proportional to parameter $t$,
and the result in such a doped insulator was interpreted in terms of
the composite nature of quasiparticles (QP) \cite{bera,bera1}.
Another evident observation is, however, the difficulty to extract a
reasonable result from studies of small systems.

The aim of this paper is to elaborate on the problem of a single hole in
a magnetic insulator in the presence of a homogeneous magnetic field.
We study the planar $t$-$J$ model \cite{rice} as a prototype model for
strongly correlated electrons and electronic properties of
cuprates,
\begin{equation}
H=-t\sum_{\langle ij\rangle s}({\rm e}^{i \theta_{ij}}
\tilde{c}^\dagger_{js}\tilde{c}^{\phantom{\dagger}}_{is}+
\text{H.c.})+J\sum_{\langle ij\rangle}\vc{S}_i\!\cdot\!\vc{S}_j ,
\label{model}
\end{equation}
where $\tilde{c}^\dagger_{is},\tilde{c}_{is}$ are fermionic operators,
projecting out states with the double occupancy. We consider the
system in a homogeneous field $B$, perpendicular to the plane, and use
for convenience the Landau gauge, where
\begin{equation}
\theta_{ij}=\f{e}{\hbar}\vc{d}_{ij}\!\cdot\!\vc{A}(\vc{r}_i),\qquad
\vc{A}=B(0,x,0),
\label{theta}
\end{equation}
with $\vc{d}_{ij}=\vc{r}_j-\vc{r}_i$. The relevant parameter for the
strength of $B$ is the dimensionless flux per plaquette $\alpha=2\pi
Ba_0^2 /\phi_0$, where $\phi_0=h/e$ is the unit quantum flux, and the
relevant regime is $-\pi <\alpha <\pi$. Further on we set the lattice
spacing $a_0=1$, as well as $h=k_B=1$.

In the following we restrict our study of the model Eq.~(\ref{model})
to the case of a single hole doped into a magnetic insulator. The idea
is that results for a single hole (spin polaron) remain relevant for
the regime of finite, but low, hole concentration $c_h \ll 1$. Here a
semiconductor-like picture implies, so that most measurable
quantities, assuming the independence of spin polarons, should simply
scale with $c_h$. E.g., the diamagnetic susceptibility should behave
as $\chi\propto c_h$.

The ground state of the spin polaron at $B=0$ has been studied
extensively both by analytical and numerical approaches, and can be
considered as one of few rather settled problems within the theory of
correlated systems. Still, here at least two substantially different
regimes have to be distinguished.

At finite $J>0$ (as relevant for cuprates with $J/t\sim0.3$) the
ground state of a hole in an antiferromagnetic (AFM) spin background
has the property of a quasiparticle (QP) with $S=1/2$ and a well
defined dispersion $\varepsilon_0(\vc{k})$. Consistent results have
been obtained for $\varepsilon_0(\vc{k})$ using the self-consistent
Born approximation (SCBA) \cite{schm,mart}, perturbation expansion
\cite{prel}, numerical approaches including both the exact
diagonalization of small systems and the quantum Monte Carlo method
\cite{dago}. Calculations reproduce a minimum at
$\vc{k}^*=(\pm\pi/2,\pm\pi/2)$, which is very anisotropic, i.e.\
$\mu=m_{\perp}/m_{\parallel}\sim5$ for $J/t\sim0.3$. This indicates a
very weak dispersion along the AFM zone boundary, connecting
$\vc{k}=\vc{k}^*$ with $\vc{k}=\vc{k}^{**}=(\pi,0)$,
$(0,\pi)$. Studying small systems \cite{dago} the latter dispersion is
not easy to reproduce correctly. E.g., on a frequently studied system
of $4\times4$ sites, states with $\vc{k}^*$ and $\vc{k}^{**}$ are
degenerate, so pronounced finite size effects are expected. Since a
small $B$ just probes the effective mass of the QP, it is not
surprising that results obtained on small lattices are not reliable or
can be even misleading \cite{bera}. On the other hand, ARPES
measurements on undoped cuprates \cite{well} show a more isotropic
minimum around $\vc{k}^*$. The explanation seems to be beyond the
simple $t$-$J$ model, and the additional effect is attributed to the
next-nearest-neighbor hopping ($t'$) term
\cite{hybe}.

The behavior at $J=0$ is quite different. As shown by Nagaoka
\cite{naga}, the ground state is ferromagnetic (FM) with $S=S_{\rm max}$
and momentum $\vc{k}=0$, where the QP is a simple hole in the filled
band of polarized electrons with an unrenormalized band mass.
Nevertheless, close to this simple QP branch there is a large density
of complicated excited states, where the hole motion is predominantly
incoherent \cite{brin}. Therefore it is expected that even moderate
temperature $T>0$ should have a considerable effect.

The paper is organized as follows. Section II is devoted to the study
of a single hole at $J=0$ and arbitrary $B$. Results are obtained via
the high-$T$ expansion and the Lanczos diagonalization technique for
small systems at $T=0$ and for $T>0$ as well. In Sec.~III we consider
the AFM case with $J>0$. Here the analysis of small systems at finite
$B$ is employed together with the study of the ground state using the
cumulant expansion in $t/J$, which has proven to be very informative
for $B=0$ \cite{prel}. In the last section, Sec.~IV, our results are
summarized and a brief discussion on the magnitude of the
susceptibility and its relation to the Hall constant is presented.

\section{$J=0$ case}

\subsection{High-$T$ expansion}

To study a single hole, as described by the model Eq.(\ref{model})
with $J=0$ and $B>0$, we first use the standard high-$T$ expansion
(HTE). Its application is in this case simple, since the only
expansion parameter is $t/T$, while $B$ remains arbitrary. The free
energy
\begin{equation}
F=-T\,{\rm ln}\, Z=-T\,{\rm ln}\,{\rm Tr}\,
e^{-\tilde{\beta}\tilde{H}},\label{free}
\end{equation}
is within the high temperature expansion expressed in terms of moments
$\mu_n$ and cumulants $\lambda_n$
\begin{eqnarray}
{\rm ln}\, Z&=&{\rm ln}\,{\rm Tr}\,1+{\rm
ln}\,\left[1+\sum_{n=1}^\infty{\frac{\tilde{\beta}^n}{n!}\mu_n}\right]
\nonumber \\
&=& {\rm ln}\,{\rm Tr}\,1+
\sum_{n=1}^\infty{\frac{\tilde{\beta}^n}{n!}\lambda_n},\label{lnz}
\end{eqnarray}
where $\tilde \beta=t/T$, $\tilde H=H/t$ and
\begin{equation}
\mu_n=(-1)^n {\rm Tr}\, \tilde H^n/{\rm Tr}\,1.\label{mu}
\end{equation}

Moments $\mu_n$ can be expressed as a sum over ${n\choose n/2}^2$
closed graphs (paths). Counting different spin configurations for
$B=0$ which remain unchanged \cite{brin} after the performed path,
each graph contributes a weight $2^{f-r+1}$. Here $f$ is the number of
cycles in the spin permutation resulting from a hole traversing the
graph, and $r$ is the number of different sites in the graph. For $B>0$
the only change comes from the contribution of the enclosed magnetic
flux, so that the weight becomes
\begin{equation}
w_n=2^{f-r+1}\,e^{im\alpha},
\end{equation}
where $m$ is the area of the graph in units of $a_0^2$.

Here it is helpful to choose a $45^\circ$ rotated coordinate system so
that a 2D graph decouples into a direct product of two 1D graphs. In
this way it is straightforward to generate nonequivalent graphs
numerically. We were able to evaluate $\mu_n$ and $\lambda_n$ up to
the order $n=18$. In Table \ref{tab1} lowest cumulants ($n\le 6$)
$\lambda_n=\sum_m\lambda_{mn}\cos m\alpha$ are presented for
illustration, while higher cumulants are available upon request.

\begin{table}
\caption{Cumulants $\lambda_n=\sum_m{\lambda_{nm}\cos m\alpha}$.}
\begin{tabular}{cccccccc}
$\lambda_{nm}$&0&$1$&2&3&4&5&6\\\hline
\r{0}&1&&&&&&\\
\r{2}&4&&&&&&\\
\r{4}&-20&2&&&&&\\
\r{6}&472&-48&$\f{3}{2}$&&&&\\
\r{8}&-24518&5992&-198&$\f{3}{2}$&$\f{1}{4}$&&\\
\r{10}&2207234&$-\f{2703635}{4}$&$\f{65195}{2}$&$-\f{1065}{2}$&
$-\f{1155}{32}$&$\f{5}{8}$&$\f{5}{32}$
\end{tabular}
\label{tab1}
\end{table}

From Eqs.(\ref{free},\ref{lnz},\ref{mu}) the series for the orbital
susceptibility (per one hole) can be generated,
\begin{equation}
\chi=\mu_0{\partial^2 F \over \partial
B^2}{\bigg\vert}_{B=0},\label{defchi}
\end{equation}
\begin{equation}
\frac{\chi}{\chi_0}=-\frac{1}{12}\tilde{\beta}^{3}+
\frac{13}{120}\tilde{\beta}^{5}-
\frac{2087}{16128}\tilde{\beta}^{7}+\frac{8161}{53760}\tilde
{\beta}^{9}-\cdots,\label{chi}
\end{equation}
where $\chi_0=\mu_0e^2a_0^4t/\hbar^2$.

There is no unique procedure for the extrapolation of the power series
Eqs.(\ref{lnz},\ref{chi}) to low $T$. For the present problem the most
reasonable approach seems to be via the density of states
$\rho(\varepsilon)$ and their moments \cite{brin},
\begin{eqnarray}
Z&=&\int{\rho(\varepsilon)\,e^{-\beta\varepsilon}{\rm
d}\varepsilon},\nonumber \\
\mu_n&=&\int{\varepsilon^n\rho(\varepsilon){\rm
d}\varepsilon}.\label{dens}
\end{eqnarray}

The density of states can be expanded in terms of Legendre
polynomials,
\begin{equation}
\rho(\varepsilon)=\sum_{\ell=0}^\infty{B_\ell{\rm
P}_\ell(\varepsilon)},\qquad
\mu_n=\sum_{\ell=0}^n{C_{n\ell}B_\ell},\label{leg}
\end{equation}
with coefficients
\begin{equation}
C_{n\ell}={\Gamma(\f{n}{2}+\f{1}{2})\Gamma(\f{n}{2}+1)\over
2\Gamma(\f{n}{2}+\f{\ell}{2}+\f{3}{2})
\Gamma(\f{n}{2}-\f{\ell}{2}+1)},\label{coef}
\end{equation}
for $n>\ell$ and even $\ell+m$, while $C_{n\ell}=0$ otherwise.

The density of states is used to extrapolate both $F$ and $\chi$ to low
$T$. After solving the linear equations
(\ref{leg}) for $B_\ell$, we can calculate the susceptibility
\begin{equation}
\frac{\chi}{\chi_0}=\frac{1}{Z\tilde\beta}
\left[\frac{\partial^2\!Z}{\partial\alpha^2}-
\frac{1}{Z}\left(\frac{\partial Z}{\partial\alpha}\right)^2\right],
\label{chit}
\end{equation}
where the same set of equations as in (\ref{dens}-\ref{coef}) holds
for derivatives with respect to $\alpha$ as well.

\subsection{Small system diagonalization}

In analysis of the $t$-$J$ model the Lanczos technique for the
exact diagonalization of small systems has been already extensively
employed \cite{dago}, predominantly in the investigation of the ground
state and their static and dynamic properties. Recently a method
combining the Lanczos procedure and the random sampling has been
introduced \cite{jakl1} which allows calculation of finite-temperature
properties in small correlated systems. The method has been used in
the study of various response function within the $t$-$J$ model at
$T>0$ \cite{jakl1}. The application is particularly simple for static
quantities, which can be expressed as expectation values of conserved
quantities \cite{jakl2}. The calculational effort is comparable to the
ground state evaluation. In particular the average energy $\langle
E\rangle$,
\begin{eqnarray}
\langle E\rangle&\approx&\frac{N_{st}}{KZ}\sum_{n=1}^{K}
\sum_{m=0}^{M-1}|\langle n|\psi_m^n\rangle|^2E_m^n
{\rm e}^{-\beta E_m^n},\nonumber\\
Z&\approx&\frac{N_{st}}{K}\sum_{n=1}^{K}
\sum_{m=0}^{M-1}|\langle n|\psi_m^n\rangle|^2{\rm e}^{-\beta E_m^n},
\label{lan}
\end{eqnarray}
should be evaluated in this way, where $|\psi_m^n\rangle, E_m^n$ are
respectively approximate eigenfunctions and energies obtained by the
diagonalization within the orthonormal set, generated from the initial
functions $|n\rangle$ in $M$ Lanczos steps. The $K$ initial functions
$|n\rangle$ are chosen at random, while $N_{st}$ is the dimension of
the complete basis. Note that it is enough to choose $M,K
\ll N_{st}$. For more detailed explanations we refer to
Refs.\cite{jakl1,jakl2}.

The introduction of finite $B>0$ in the model, Eq.(\ref{model}),
reduces the translational symmetry and thus for a given system size
increases the required minimal basis set. We are at present able to
consider the problem of a single mobile hole in canonical 2D systems
with $N = 16,18,20$ sites \cite{oitm}, and periodic boundary
conditions (p.b.c.).

It is nontrivial to incorporate phases due to a homogeneous $B$, being
at the same time compatible with p.b.c. It is well known \cite{frad}
that this can be accomplished only for quantized magnetic fields $B=m
B_0$, where $B_0=\phi_0/N$ is the smallest field corresponding to the
unit quantum flux per system. To incorporate such $B$ in small systems
(tilted squares), the following procedure is used: a) phases
$\theta_{ij}$ for all hops inside squares are left as given within the
particular Landau gauge, b) phases attributed to hops across the
square boundaries are subject to the condition that the magnetic flux
in each plaquette remain the same, i.e.\ $B'\equiv B~\rm{mod}(\phi_0)$
(up to the addition of an unit flux per plaquette). These boundary
requirements lead to a set of linear equations which have solutions
only for $B=mB_0$. Only for an untilted square lattice with $N=L\times
L$ sites the phases can be expressed in a simple form as
\begin{eqnarray}
\theta_{(i_x,i_y)(i_x,i_y+1)}&=& B i_x , \nonumber\\
\theta_{(i_x,i_y)(i_x+1,i_y)}&=& 0,\qquad\quad i_x<L,\nonumber\\
\theta_{(L,i_y)(1,i_y)}&=& B i_y L.
\label{bound}
\end{eqnarray}

\subsection{Results}

Let us first discuss the polaron internal energy
$\langle\varepsilon(\alpha)\rangle$ as obtained from the high-$T$
expansion
\begin{equation}
\langle\varepsilon\rangle=-{\partial({\rm ln}\,Z)\over\partial\beta}=
-t\sum _{n=0}^\infty{{\tilde\beta}^n \over n!}\lambda_{n+1}.
\label{energ}
\end{equation}
From cumulants $\lambda_{nm}$ in Table I we see that the $\alpha$
dependence of $\langle\varepsilon\rangle$ first enters within the
order $\tilde\beta^3$. Such a term originates from a hole hopping
around a loop, contributing to ${\rm Tr}\,\tilde H^4$ when all spins
are equally polarized, in analogy to the processes contributing to the
Hall constant \cite{brin1}. As a result, $\alpha$ dependence of
$\langle\varepsilon\rangle$ is vanishing fast ($\propto(t/T)^3$) for
$T>t$.

\begin{figure}[t]
\begin{center}
\iffigure
\epsfig{file=fig1.eps,width=8cm}
\fi
\end{center}
\caption{Polaron energy $\langle\varepsilon\rangle$ (in units of $t$)
for $J=0$ at two different temperatures, as a function of
dimensionless magnetic field $\alpha$. Full line represents high-$T$
expansion results, while open and full dots correspond to results on
systems with $N=16,18$ and $20$ sites, respectively.}
\label{fig1}
\end{figure}

In Fig.~\ref{fig1} we present $\langle\varepsilon(\alpha)\rangle$ for
lower $T$, i.e.\ $T=t$ and $T=0.2~t$. The results of the high-$T$
extrapolation and finite size calculations performed for $N=16,18$ and
20 are compared. For most points the agreement between both methods is
quite satisfactory. On the other hand, there are clearly visible
anomalies at $\alpha = n \pi/2$ for $N=16$ and less pronounced at
$\alpha=0$ for $N=18, 20$. It is straightforward to explain these
discrepancies within the high-$T$ expansion. In small systems there
are some additional processes due to p.b.c., which lead to changes of
$\langle\varepsilon(\alpha)\rangle$ relative to an infinite system.
E.g., in the $N=4\times4$ system contributions from graphs in lowest
field-dependent order $\tilde{\beta}^3$, representing four consecutive
hops in the $x$- or $y$-direction cancel, except for $\alpha= n
\pi/2$, changing the cumulant
\begin{equation}
\Delta\lambda_4=1,
\end{equation}
as seen in Fig.~\ref{fig1}.

It should be observed that for $N=16$ this correction to $\langle
\varepsilon\rangle$ is within the leading order of $\tilde\beta^3$,
while analogous corrections in larger systems, e.g.~for $N=18$, emerge
only in higher orders. This confirms that on small systems the
calculation of $B$-induced diamagnetic currents is more delicate than
the evaluation of most of the static polaron properties. Nevertheless,
at $J=0$ finite size effects are rather well under control, at least
in comparison to the AFM case $J>0$ presented in Section III.

Consistency of high-$T$ expansion and small system ($N>16$) results
allows reliable extrapolation of the susceptibility $\chi$ to quite low
$T\sim 0.1~t$, using the procedure via the density of states
$\rho(\varepsilon)$, Eqs.(\ref{dens}-\ref{chit}). The result is
presented in Fig.~\ref{fig2}, and as expected $\chi$ is
diamagnetic. While for $T\gg t$ the susceptibility $\chi$ is
proportional to $\beta^3$, the variation is less steep for
$0.1~t<T<t$, where the variation is closer to
$\chi\propto\beta^{\eta}$ with $\eta<1$.

\begin{figure}[t]
\begin{center}
\iffigure
\epsfig{file=fig2.eps,height=8cm,angle=-90}
\fi
\end{center}
\caption{Susceptibility $\chi$ vs.~$T/t$, obtained by the high-$T$
expansion.}
\label{fig2}
\end{figure}

It is quite delicate to approach $T=0$ within the $J=0$ model. The
ground state for a single hole is within the sector of maximal total
spin $S=S_{\rm max}$ \cite{naga}, however excited states are numerous
and close in energy, so that the transition between the regime of an
incoherent hole propagation and the regime of the large FM polaron
appears to happen at surprisingly low $T^*/t \sim 0.1$. This is
consistent with the well established fact that the FM-polarized ground
state is very sensitive to any change of parameters. The behavior of a
single hole is simple only strictly at $T=0$. It is expected that the
QP at $B=0$ behaves according to the Nagaoka theorem, i.e.\ as a free
hole with energy $\varepsilon=-4~t$ in a filled band of spinless
fermions. Looking only in the sector $S=S_{\rm max}$, a finite field
($B>0$) should increase the ground state energy according to the
cyclotron frequency, i.e.\ $\delta
\varepsilon\sim eB/m^*=Bt$.

In Fig.~\ref{fig3} we show both the absolute g.s.\ energy
$\varepsilon$ and the lowest energy in the sector $S=S_{\rm max}$ as
calculated within small systems with $N=16,18$ and 20. For the Nagaoka
sector $S=S_{\rm max}$ the behavior is for $\alpha < \pi/4$ clearly of
the cyclotron type, while for higher $\alpha$ there are some visible
commensurability anomalies identical to the study of spinless fermions
in a magnetic field \cite{kohm}. On the other hand, deviations of the
absolute ground state from the naive result are much more
pronounced. First, even the smallest $B=B_0$ leads to the instability
of the $S=S_{\rm max}$ state, and the actual spin of the g.s.\ is
$S<S_{\rm max}$. Nevertheless, $\delta\varepsilon$ remains quite close
to the cyclotron value. For higher $B>B_0$ the ground state saturates
quite abruptly to lowest spin $S=1/2$ and g.s.\ energy $\varepsilon$
is much lower than in the $S=S_{\rm max}$ case. Note, however, that
even an approximate validity of the simple cyclotron-frequency
argument, $\delta\varepsilon\propto|B|$, implies a divergent
susceptibility $\chi(T$$\to$$0)\to\infty$, as found also from the
high-$T$ expansion.

\begin{figure}[t]
\begin{center}
\iffigure
\epsfig{file=fig3.eps,height=8cm,angle=-90}
\fi
\end{center}
\caption{Ground state energy $\varepsilon$ (in units of $t$)
vs.~$\alpha$, obtained via the diagonalization of small systems of
different sizes and $J=0$. Open dots correspond to the lowest-energy
state within the sector $S=S_{\rm max}$.}
\label{fig3}
\end{figure}

\section{$J>0$: Antiferromagnetic spin background}

$J>0$ introduces quite a different QP behavior. At $T=0$ the spin
background corresponds to an AFM with long range order. The ground
state of the spin polaron is well understood, and corresponds within
the $t$-$J$ model to $S=1/2$ and $\vc{k}=\vc{k}^*$, with a weak
dispersion along the AFM zone boundary.

At least for weak magnetic fields it is expected that the QP
description of the hole is still valid, resulting in a cyclotron
motion with the linear-in-field dependence of the QP energy. Such
behavior, is questioned by recent small-system diagonalisation results
\cite{bera}. It should be reminded that results obtained from
the exact diagonalisation can be misleading due to finite size
effects, if the cyclotron radius is comparable to the linear size of
the system. With p.b.c.~even more pronounced effects compared to those
already discussed for $J=0$ in Sec.~II can be expected. For the AFM
case they arise from larger ground state degeneracy, and from the
near-degeneracy of the QP dispersion along the AFM zone boundary.

\subsection{Cumulant expansion method}

At $T$=$0$ we can consider a QP moving in an ordered AFM by performing
the expansion starting in the limit $t/J \ll 1$. Here the standard
cumulant-expansion (CE) procedure for the ground-state energy, as
first considered by C.~Bloch \cite{bloc}, is followed.

The implementation of the method in the zero-field case with a single
hole in the $t$-$J$ model has been already given in some detail
elsewhere \cite{prel}. There the diagonal part of the Heisenberg spin
interaction in Eq.~(1) has been taken as the unperturbed Hamiltonian
$H_0$ and the ground-state energy $\varepsilon_0(\vc{k})$, expressed
relative to the undoped AFM ground state, has been obtained as a
double power series in $u=t/J$ and $\gamma = J_\perp /J$
\begin{equation}
\varepsilon_0(\vc{k})=J\sum_{n,m}a_{n,m}(\vc{k})u^n({\gamma\over
2})^m\,,
\end{equation}
where the $\vc{k}$-dependence of the expansion coefficients merely
reflects the underlying translational invariance of the problem.

A finite magnetic field breaks the translational invariance of the
system, so the above result, obtained from the nondegenerate theory is
not valid. Indeed, the unperturbed ground state becomes highly
degenerate, allowing for any hole position in an otherwise perfectly
N\'eel-ordered spin state, thus the degenerate perturbation theory
must be used. The version of the secular determinant as given in
\cite{mess} is used, which up to the fourth order in perturbation $H'$
reads
\begin{eqnarray}
(E&-&E_0)\delta_{ij}\nonumber\\&=&<i|H'{Q_0\over \eta_0}H'|j>+
<i|H'{Q_0\over\eta_0}H'{Q_0\over\eta_0}H'{Q_0\over \eta_0}H'|j>\nonumber\\
&-&\sum_\ell<i|H'{Q_0\over\eta_0}H'|\ell><\ell |H'{Q_0\over
\eta_0^2}H'|j>\nonumber\\
&+&\cdots
\label{dpex}
\end{eqnarray}
The (bra)kets denote the set of degenerate states -- positions of the
hole -- with the unperturbed energy $E_0$, whereas $P_0$ and $Q_0$ are
the projectors onto this subset of states and its complement,
respectively. $H'$ is taken to be the sum of the hopping part and the
transverse spin part of $H$ in (1), while $\eta_0$ stands for the
energy denominator $E_0-H_0$. A contribution to the matrix element
$M(i,j)=<i|\cdots |j>$ resulting from a particular process $\cal
O_\mu$ involving products of operators as in (\ref{dpex}) is
calculated from the associated graph \cite{prel,bloc} in any order of
perturbation expansion. However, as the hole moves from some initial
position $i$ to a final but equivalent position $j$ under the action
of a particular string of operators $\cal O_\mu$ along some path, it
acquires a definite phase factor $\theta_{ij}$, depending on the path
itself. Two such paths are depicted in Fig.~\ref{fig4}.

In the chosen Landau gauge the phase associated with any link in the
$y$-direction is given by the $x$-coordinate of that link. Thus, the
total phase $\theta_{ij}$ acquired by the hole along the path $\cal
C$, is
\begin{equation}
\theta_{ij}({\cal C})=\int_{\cal C}\vc{A}\cdot {\rm d}\vc{s}
= i_x(j_y-i_y)\alpha + \phi_{ij}({\cal C}).
\end{equation}
Here $\phi_{ij}({\cal C})$ is the phase relative to the initial point
at $i$. Care should be taken of the proper orientation in which the
link is traversed. Thus, referring to Fig.~\ref{fig4}, phase along
${\cal C}_\mu$ is $\phi= -2\alpha$, whereas along the path ${\cal
A}_\mu$ $\phi= 4\alpha$.

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  \put(30,1.5){\makebox(0,0)[b]{\mysize{$i_x+1$}}}
  \put(40,1.5){\makebox(0,0)[b]{\mysize{$i_x+2$}}}
  \put(50,1.5){\makebox(0,0)[b]{\mysize{$i_x+3$}}}
  \put(30,-4){\makebox(0,0)[b]{\mysize{phase $\to$}}}
\end{picture}
\end{center}
\caption{The phase increments, defined on the (oriented) links between
two neighboring lattice points, in the Landau gauge $\vc{A}=B(0,x,0)$
along two different paths ${\cal C}_\mu$ and ${\cal A}_\mu$
connecting points $i$ and $j$.}
\label{fig4}
\end{figure}

We have generated all the paths in order $u^n\gamma^m$ with $(n,m)$ up
to $(2,4)$, $(4,4)$, $(6,3)$ and $(8,2)$. Each contribution to the
perturbation series in order $(n,m)$ is then given by the magnitude
$\omega(i,j)$ of the matrix element $\langle i|{\cal O}_\mu^{(r)}|
j\rangle$ and the phase $\theta_\mu(i,j)$, where ${\cal O}_\mu^{(r)}$
refers to a definite product of operators of order $r=n+m$ along the
path from $i\to j$ \cite{prel}.

The secular equation (\ref{dpex}) becomes a difference equation for the
on-site amplitudes $f_i$ on a rectangular grid with $N=L_x\times L_y$
sites
\begin{eqnarray}
\varepsilon f_i&=&\sum_{j} M(i,j) f_j,\nonumber\\
M(i,j)&=&\sum_{n,m}u^n\gamma^m \sum_{{\cal C}_\mu}\omega_\mu(i,j )
e^{\imath\theta_\mu(i,j)},\label{sr2d}\nonumber\\
\end{eqnarray}
where $i$ and $j$ run only over one sublattice, $M(i,j)$ is a sum of
contributions along different paths ${\cal C}_\mu$, and the energy
$\varepsilon\equiv\varepsilon(\alpha)$ is again measured with respect
to the g.s.\ of the undoped AFM state. Referring again to
Fig.~\ref{fig4} the paths ${\cal C}_\mu$ and ${\cal A}_\mu$ would then
first appear in order $u^8\gamma^4$ and $u^4\gamma^2$, respectively.

In the chosen gauge Eq.~(\ref{theta}), the system is translationally
invariant along the $y$-direction. Thus, the ansatz
$f_i=g_{i_x}\exp(\imath k_y i_y)$ reduces the above equation to a
difference equation in one dimension, where $\ell=i_x$,
\begin{eqnarray}
\varepsilon g_\ell=&&\sum_{\ell'} {\widetilde
M}(\ell,\ell')g_{\ell'},\qquad 1\le \ell,\ell'\le
L_x,\nonumber\\
{\widetilde M}(\ell,\ell')={\sum_\tau}'e^{\imath\tau
Q}&&\sum_{n,m}u^{n}\gamma^m
\sum_{{\cal
C}_\mu}\omega_\mu(\ell'-\ell,\tau)e^{\imath\phi_\mu(\ell'-\ell,\tau)}
\nonumber\\ Q=&&k_y+\alpha \ell,\label{eige}
\end{eqnarray}
and the summation over $\tau$ is restricted to run over values for which
$\ell'-\ell+\tau$ is even, whereas $k_y\in
\lbrack0,2\pi\rbrack$. Note also that $\omega$ and $\phi$ do not
depend on the initial point $\ell$, but only on the path $\cal
C$. Taking $\alpha=2\pi p/L_x$, one can impose the p.b.c.~also in the
$x$ direction.

The eigenvalue problem of Eq.(\ref{eige}) is solved numerically for
$L_x\gg\xi$, where $\xi=13$ is the smallest linear size of the region
visited by the hole, within the order of perturbation series here
considered. In Fig.~\ref{fig5} we plot the g.s.\ energy $\varepsilon$
as a function of $\alpha$ at $J/t=2$ and the isotropic exchange
$\gamma=1$, evaluated for $L_x=128$. A linear-in-field dependence of
$\delta\varepsilon(\alpha)=\varepsilon(\alpha)-\varepsilon(0)$ in
Fig.~\ref{fig5} is evident for small $\alpha$, implying that the hole
may still be described as a QP exhibiting cyclotron motion. However,
after the initial rise an almost monotonic decrease is observed and
the minimum of $\varepsilon(\alpha)$ is achieved for $\alpha=\pi$.
The figure includes also the respective data from exact
diagonalization for $N=20$. Although both sets of data do not agree in
detail, which can be partially attributed to the perturbational
character of the CE results, the overall behavior is remarkably
similar, including the initial rise in $\delta\varepsilon(\alpha)$ for
$N=20$ and the cusp-like behavior close to $\alpha=\pi/2$. This holds
to a lesser degree for other commensurability points, e.g.\ for
$\alpha=\pi/4$ and $3\pi/4$.

\begin{figure}[t]
\begin{center}
\iffigure
\epsfig{file=fig5.eps,height=8cm,angle=-90}
\fi
\end{center}
\caption{Ground state energy difference
$\delta\varepsilon(\alpha)=\varepsilon(\alpha)-\varepsilon(0)$
(in units of $t$), as obtained for $t/J=0.5$ and $\gamma=1$ from
the cumulant expansion method. For comparison small-system data for
$N=20$
are also included ($\blacklozenge$)}
\label{fig5}
\end{figure}

The experimentally relevant value of $J/t$ is $\sim 0.3$.
Technically, it is possible to perform a Pad{\' e}-like extrapolation
of $\varepsilon(\alpha)$ to larger values of $u$, in analogy to the
$B=0$ case \cite{prel}. Still we do not attempt to perform such an
extrapolation here. Relying on previous experience
\cite{prel} that no crossover in the QP behavior sets in down to $J/t
\ll 1$ (where Nagaoka regime takes over) we believe that the qualitative
conclusions on QP behavior for finite $B$ remain valid in the
physically relevant regime $J<t$ as well.

\subsection{Small-system results}

Using the numerical finite temperature technique described in Sec.~IIB
and applied to the $J=0$ case the results for $J>0$ are also
obtained. In the following we choose $J/t=0.4$, which is close to the
situation in cuprates, and consider the contribution of the single
hole energy $\varepsilon=E(N_h$=$1)- E(N_h$=$0)$ to the internal
energy at $T=0$ and $T>0$ ($\langle\varepsilon\rangle$). First note
that for $T\gg {\rm max}(t,J)$, the leading order of the high-$T$
expansion is independent of $J$ and in this limit results for $J=0$
and $J>0$ match.

In Fig.~\ref{fig7} the intermediate temperature hole energies
$\langle\varepsilon(\alpha)\rangle$ are evaluated at two different $T$
within different system sizes. Comparing results with those for $J=0$
in Fig.~\ref{fig1}, several conclusions can be reached. At higher
$T/t=1$ energies $\langle\varepsilon(\alpha)\rangle$ for $J=0$ and
$J/t=0.4$ are qualitatively similar. As a function of $\alpha$ both
cases correspond approximately to the simple $\cos
\alpha$ variation. It is however evident that finite $J$ considerably
reduces (by a factor $\sim 4$) the total energy span.

Relative to the $J=0$ case it is also clear that finite size effects
become more pronounced when approaching the low-$T$ regime. This is
related to the near-degeneracy of the quasiparticle dispersion
$\varepsilon_0({\vc k})$ at the bottom of the QP band, which is poorly
reproduced in small systems. Nevertheless, numerical results establish
quite consistently the crossover at $T\sim T^*\propto J$.

For $T<T^*$ energy $\langle\varepsilon(\alpha)\rangle$ shows an
overall opposite, i.e.\ a paramagnetic-like variation with $\alpha$,
as found in \cite{bera} and reproduced above within the CE with
respect to $t/J$. The results in this temperature region are more size
dependent. At $T/t=0.2$ in Fig.~\ref{fig7} we can find a maximum for
$\alpha>0$ only in systems with $N=18,20$ sites, while the $N=16$ case
shows a different behavior. The deviation within the latter system is
due to additional symmetry of the $4\times4$ system (hypercube).

\begin{figure}[t]
\begin{center}
\iffigure
\epsfig{file=fig7.eps,width=8cm}
\fi
\end{center}
\caption{Single hole energy $\langle\varepsilon\rangle$ vs.~$\alpha$ for
$J/t=0.4$ at two different $T/t$, as calculated on a system of $N=16,
18, 20$ sites.}
\label{fig7}
\end{figure}

Quite similar results are obtained for the ground state energy
$\varepsilon$, shown in Fig.~\ref{fig8}. Again, $N=18$ and $N=20$
systems yield very similar $\varepsilon(\alpha)$, while $N=16$ results
deviate especially for `commensurate' values $\alpha=0,\pi/2, \pi$.
The qualitative trend of $\varepsilon(\alpha)$ agrees well with the CE
results on Fig.~5. The similarity is in the existence of (rather
shallow) maximum at low $\alpha$ for largest $N$, indicating a QP
behavior with a cyclotron motion in weak $B$ and also a pronounced
reduction of $\varepsilon$ for $\alpha >\pi/2$. The only difference is in
the absence of commensurability dips in Fig.~8, which we attribute to
the very particular system shapes used in the calculation, and to the
almost degenerate dispersion along the magnetic Brillouin zone
boundary.

\begin{figure}[t]
\begin{center}
\iffigure
\epsfig{file=fig8.eps,height=8cm,angle=-90}
\fi
\end{center}
\caption{Ground state energy $\varepsilon(\alpha)$ for
$J/t=0.4$, as calculated on systems of
$N=16, 18, 20$ sites.}
\label{fig8}
\end{figure}

Finally, let us present in Fig.~\ref{fig9} results for the orbital
susceptibility $\chi(T)$, Eq.(\ref{defchi}). For $J=0$ the calculation
is performed via high-$T$ expansion as already discussed in Sec.~2.
Since we rely only on discrete values of $\alpha$, the analysis of
finite-system data for $J/t=0.4$ is on the other hand less reliable.

\begin{figure}[b]
\begin{center}
\iffigure
\epsfig{file=fig9.eps,height=8cm,angle=-90}
\fi
\end{center}
\caption{Susceptibility $\chi$ vs.~$T/t$ for $J/t=0.4$, as extracted
from small-system data $N=18,20$.}
\label{fig9}
\end{figure}

Moreover, the variation of $F(\alpha)$ is quite subtle at smallest
$\alpha_{\rm min}$, as evidenced also from $\varepsilon$ in
Fig.~\ref{fig8}. In Fig.~\ref{fig9} the susceptibility $\chi$ is
presented as obtained from Eq.(\ref{defchi}), with parabolic fit for
$F(\alpha)$ using only $\alpha=0$ and $\alpha=\alpha_{\rm min}$. This
procedure could be questionable for $T<T^*$, but qualitative behavior
is still quite instructive. Relative to the $J=0$ case, the
diamagnetism is suppressed by $J>0$ at higher $T\gg J$. In an
intermediate regime $T\sim J$, susceptibility $\chi$ appears even to
change sign, i.e.\ becomes paramagnetic. Only at low $T<T^*$ a
pronounced strongly $T$-dependent diamagnetic response is again
observed, consistent with the QP cyclotron motion at $T=0$. It is an
interesting observation that an exact solution of the problem on a
single plaquette (at $T>0$) subjected to an effective staggered AFM
field, reproduces qualitative features of Fig.~\ref{fig9}.

\section{Conclusions}

Our study shows that the calculation of the effects of finite magnetic
field, coupled to orbital motion of electrons, becomes delicate in
models of correlated electrons, e.g.\ within the $t$-$J$ model
considered in this work. Results for magnetic observables such as the
diamagnetic susceptibility appear to be strongly influenced by
finite-size effects, which are hard to overcome in available system
sizes. Both for $J=0$ and $J>0$ some of deviations appear at
`commensurate' values of $\alpha$ within the given system geometry,
and are particularly large for $N=16$. We have shown that it is
possible to understand such finite-size effects within the high-$T$
expansion or within the $t/J$ perturbation expansion as a contribution
of additional graphs due to p.b.c. Still it is impossible to
eliminate them systematically in most interesting physical
regimes. These effects lead to a nonmonotonous variation of
observables, e.g.\ $\langle\varepsilon(\alpha)\rangle$, which in turn
leads to an enhanced uncertainty in $\chi(T)$.

The $J=0$ case seems both easier to study and to understand. High-$T$
expansion and small systems show a continuous transition from the
high-$T$ regime of incoherent hopping to the Nagaoka state at $T=0$,
with a monotonous increase of the diamagnetic $\chi$. At $T>0$ where
the HTE is reliable the variation of the energy with field
$\langle\varepsilon(\alpha)\rangle$ is quite close to a simple
$\cos\alpha$ form. Nevertheless the asymptotic behavior at low $T$ is
not simple to establish, since the nature of low lying states (above
the Nagaoka state) is complicated.

The behavior of the AFM $J>0$ polaron is more involved. While at $T\gg
J$ the exchange scale $J$ is not important and results qualitatively
follow those for $J=0$, new physics emerges for $T\lesssim J$. A
nearly flat $\langle\varepsilon(\alpha)\rangle$ at intermediate regime
$T\sim J$ is quite remarkable, and leads to a vanishing diamagnetic
$\chi$ (or even change of its sign). It seems, that here $J>0$
diminishes and even destroys emerging coherence of QP. Only at lower
$T<J$ the coherence is established and the known dynamical picture of
a coherent AFM polaron is dominating the behavior in lowest fields
$\alpha$. Reliable results are however difficult to obtain even for
$T=0$, since in small systems their variation with $\alpha$ is very
sensitive to the system shape, boundary conditions etc.\ due to the
very anisotropic and degenerate QP dispersion.

The CE results are very instructive, but it is not straightforward to
make them quantitative for $J<t$. For $J>t$, where the CE series
converges quite rapidly, there is a clear evidence in weak fields that
the QP is exhibiting cyclotron motion. The commensurability effects
are quite pronounced and agree with finite-cluster data for large
$J/t>1$, see Fig.~\ref{fig5}. On the other hand, these effects are not
evident in small-system results for $J/t<1$. This non-agreement is
attributed in part to specific lattice shapes and p.b.c. The flatness
of the dispersion seems to be the main reason for the structureless
character of small-system data in the region of small $\alpha$ for
$J/t<1$.

Here we would like to point to the close similarity with the
challenging theoretical problem of the Hall effect, which is difficult
to approach even for very low doping, e.g.\ for a single hole
\cite{prel1}. Similarly to the orbital susceptibility the Hall effect
emerges due to coupling to orbital currents. The Hall constant is
given by $R_H=\sigma_{xy}/B\sigma_{xx}^2$, where the off-diagonal
conductivity $\sigma_{xy}$ can be related to the orbital
susceptibility $\chi$ as
\cite{rojo}
\begin{equation}
\sigma_{xy}=B\frac{\partial\chi}{\partial c_h}
\frac{\partial c_h}{\partial \mu},
\end{equation}
where $\mu$ is the chemical potential. In our case of very low hole
doping, i.e.\ in the semiconductor-like regime, the susceptibility
$\chi$ scales linearly with $c_h$; moreover $\partial
c_h/\partial\mu=-\beta c_h$, so that $\sigma_{xy}\propto\chi$. The
high-$T$ expansion of the Hall constant $R_H^*(T)$ (the high-frequency
value) is analogous to that of $\chi(T)$ \cite{brin1}. On the other
hand, crossing the scale $T\sim J$ remains the challenge, whereby it
seems that at this intermediate $T$ the hole-like $R^*_H$ is even
reduced with respect to its high-$T$ value \cite{brin1,assa}.
Experiments \cite{ong} indicate, that $R_H$ recovers for $T<T^*$,
varying strongly with $T$ and approaches the well known quasiclassical
result for $T\to 0$ \cite{prel1}. Note that our results for $\chi(T)$,
Fig.~\ref{fig9}, indicate just on such behavior.

Let us finally comment on the magnitude of the diamagnetic
susceptibility. Since we are evaluating the case of a single hole, at
low doping $c_h\ll 1$ the observable diamagnetic contribution to the
susceptibility (per unit cell) should be $\chi=\zeta c_h\chi_0$, where
$\zeta$ is dimensionless value, presented in Figs.~\ref{fig2}
and~\ref{fig9}. It is convenient to compare these values to the spin
susceptibility (per unit cell) of the planar undoped AFM for $T<T^*$,
where $\chi_s\sim4.0\mu_0\mu_B/J$ \cite{jakl2,sing}. Setting
$m_t=\hbar^2/2ta_0^2$ the ratio can be expressed as
\begin{equation}
\frac{\chi}{\chi_s}=K\zeta c_h\frac{J}{t}\left(\frac{m_e}{m_t}\right)^2,
\label{rat1}
\end{equation}
where $K\sim 2.8$ is a numerical constant. Taking the standard values
for cuprates $t=0.4$ eV, $J/t=0.3$ and $a_0=0.38$ nm, the above
relation reduces to $\chi/\chi_s\sim1.9\,c_h\,\zeta$.

Another relation can be obtained for the Pauli susceptibility of a
half-filled band of free tight-binding electrons, where a constant
(average) density of states is assumed for simplicity. This gives a
similar relation
\begin{equation}
\frac{\chi}{\chi_P}=K'\zeta c_h\left(\frac{m_e}{m_t}\right)^2
\sim9.3\,c_h\,\zeta\,,
\label{rat2}
\end{equation}
with $K'\sim 4.0$. To estimate the actual value of $\chi/\chi_s$ in
Eq.~(27) we take $c_h\sim 0.15$, e.g.\ as in the 'optimal' doping
regime, and $\zeta\sim-0.1$ in the region $T<T^*$. This gives
$\chi/\chi_s\sim-0.03$, which is of the same order of magnitude as the
experimentally measured value \cite{wals}. Note, however, that below
the crossover temperature $T^*$ $\zeta$ becomes strongly temperature
dependent, as opposed to the usual $T$-independent Landau-type
diamagnetism in Fermi liquids. Since it is difficult to distinguish
different contributions to the actual susceptibility in experiments,
it remains to be seen whether such $T$-dependent $\chi$ really appears
in cuprates and analogous systems.

\acknowledgements

One of the authors (P.P.) wishes to thank X.~Zotos for helpful
suggestions concerning the introduction of a magnetic field in small
systems.

This work was supported by Ministry of Science and Technology of
Slovenia under Project No.\ J1-6166-0106/97.

\vspace{5mm}
* E-mail: \verb|darko.veberic@ijs.si|

redpajama_set_name: RedPajamaArXiv


Around the globe, snow enthusiasts will celebrate World Snow Day on January 15, 2017. The goal is giving children ages four to 14 a better understanding of winter sports. Snowshoeing, sledding, cross-country skiing, snowboarding, or alpine skiing: The selection of unique snow experiences is vast.
Children all over the world love snow. Here, a girl cross-country skiing in Russia.
Around the world, more than 586,000 participants joined in at the 625 events in a total of 42 countries for World Snow Day. Under the slogan "Explore – Enjoy – Experience," children from all over the world are meant to get to know the magic of snow.
With the early onset of winter in November, there's also the hope for a lot of snow. There's no lack of excitement for sports, as shown by the success of the World Snow Day in January 2016. The final report from 2016 predicts that 93% of participants will also want to be there in 2017.
Among the sponsors for World Snow Day are the International Ski Association (FIS), the World Federation of the Sporting Goods Industry (WFSGI), the Federation of the European Sporting Goods Industry (FESI), as well as the winter sports companies Atomic, Elan, Nordica, and even Salomon.


HRC Fertility Clinic – ACCESS ELECTRIC, INC.
Complete electrical system for new 2 suite, 2 story fertility clinic at Hoag Hospital, Newport Beach. Work included power, lighting, new panels and switchboard, installation of Generator for complete power for one suite and lighting on the second suite. HVAC power on roof and exhaust fans. Rough-in power for O.R. Room, power for Recovery Beds, Med Gas, and Low Voltage for telephone, data, nurse call. Fire Alarm conduit and boxes and power to Fire Alarm Panel.
Electrical Design: OMB Electrical Engineers, Inc.
General Contractor: KPRS Construction Services, Inc.


The wheatgrass juice is rich in Chlorophyll. The molecular structure of the Chlorophyll is very similar to that of Hemoglobin in blood.
The difference between Hemoglobin and Chlorophyll is that the central atom in Hemoglobin contains Iron, whereas, the central atom of Chlorophyll contains Magnesium.
Chlorophyll contains oxygen, carbon, nitrogen, hydrogen and magnesium, whilst haemoglobin from the blood contains iron at the place of magnesium, see figure above. Both iron and magnesium are metallic atoms.
The close similarity between blood and chlorophyl, plants are producers (they make their own food using energy and materials from their environment) and animals are consumers (cannot make their own food). Chlorophyll, hemoglobin and hemacyanin are three fundamental molecules of life as we know in our planet. Their chemical formulas are: C55H72O5N4Mg, for chlorophyll, and for hemoglobin is C2952H4664N812O832S8Fe4.
Wheatgrass juice is a highly nutritious food. It is high in vitamins A and E, as well as the B vitamins. It contains many minerals and trace elements needed by the body. It contains Calcium, Phosphorus, Sodium, Potassium, Magnesium, Iron and Zinc. It also contains twelve amino acids, including the seven essential amino acids. It is important to note that enzymes such as Amylase, Protease and Lipase were not detected in this laboratory analysis. Wheatgrass juice is considered a predigested food. It does not require enzymes for breakdown of proteins. Both amino acids and glucose are present in the juice and are, therefore, readily assimilated by the body.
The wheatgrass juice is rich in Chlorophyll. The molecular structure of the Chlorophyll is very similar to that of Hemoglobin in blood. The difference between Hemoglobin and Chlorophyll is that the central atom in Hemoglobin contains Iron, whereas, the central atom of Chlorophyll contains Magnesium.
It is the Iron in wheatgrass juice which helps the blood carries healing Oxygen to all the cells. Wheatgrass juice also aids in detoxification by breaking up impacted matter in the colon. It is a valuable tool in the bodies' natural self-healing, because it helps fight infection.
Sunflower and buckwheat greens, collectively referred to as "the greens", are valuable sources of enzymes and amino acids. They are high in vitamin D, as well as Chlorophyll and Lecithin. They are low in fat and contain no starch, so the body does not have to spend much energy to digest them. They are also, therefore, an efficient energy source.
Chlorophyll is the first product of light and therefore contains more light energy than any other element.
Wheatgrass juice is a crude chlorophyll and can be taken orally & as colon implant without toxic side effects. Chlorophyll is the basic of all plant life. Wheatgrass is high in oxygen like all green plants that contain chlorophyll. The brain and all body tissues function at an optimal level in a highly-oxygenated environment. Chlorophyll is antibacterial and can be used inside and outside the body as a healer.
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Pour green juice over your body in a tub of warm water and soak for 15 to 20 mins. Rinse off with cold water.
Wheatgrass implants (enemas) are great for healing and detoxifying the colon walls.
The implants also heal cleanse the internal organs.
Wheatgrass juice is great for constipation and bowels open. It is high in magnesium.
Wheatgrass juice can dissolve the scars that are formed in the lungs from breathing acid gasses.
The effect of carbon monoxide is minimized since chlorophyll increase hemoglobin production.
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In "The American Journal of Surgery" (1940) Benjamin Cruskin, M.D., recommends chlorophyll for its antiseptic benefits. The article suggests the following clinical uses for chlorophyll.
It neutralizes strep infections, heals wounds, hastens skin grafting, cures chronic sinusitis, overcomes ear inflammation and infections, reduces varicose veins and heals leg ulcers, eliminates impetigo and other scabby eruptions, heals rectal sores, successfully treats inflammation of the uterine cervix, gets rid of parasitic vaginal infections, reduces typhoid fever, and cures advanced pyorrhea in many cases.
Dr. Birscher, a research scientist in Switzerland, called chlorophyll "concentrated sun power." He said, "Chlorophyll increases the function of the heart, affects the vascular system, the intestines, the uterus, and the lungs. According to Dr. Birscher, nature uses chlorophyll (wheatgrass) as a body cleanser, rebuilder, and neutralizer of toxins.
Choose any type of container for sprouting wheatgrass. Pots that have drainage holes are the easiest to use for beginner sprouters but once you get a handle on how much water wheat sprouts require, you can sprout them in any container that is at least 3-4" deep. Select a growing medium: Once you've decided on a container, fill it to about 1 inch below the top of the rim with premoistened soil, compost or potting mix. Make that sure whatever growing medium you use, it doesn't contain any artificial fertilizers or chemicals. Soak the wheat in water overnight. Wheat seeds are sometimes sold as wheat "kernels" or as "Hard Red Wheat." Sprinkle the top of your container with soaked wheat seed. Leave a little bit of space between the seeds, so that they're not touching and competing for food.
Press the seed into the soil and then cover lightly with more potting mix or soil and water lightly. The soil needs to be kept moist, so cover your containers with a clear plastic bag or clear plastic film. In about 3-4 days, you will begin to see sprouts emerge. It's now time to move the container to a sunny location. Sunshine not only allows the young sprouts to manufacture more chlorophyll, but it helps to keep them stocky and short. Wheatgrass grown in the dark or in poorly lit areas tends to be quite pale and lanky and in no time at all, the sprouts begin to fall over. By about 7-10, the sprouts are the perfect height to use as a centerpiece or to begin harvesting for juice. Wheatgrass can be cut more than once for an extended harvest so if you are using it for juice, start a few containers on different days so that you have a continuous supply of the nutritious leaves.


text:
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ISL 2018-19, Jamshedpur vs Bengaluru FC, Highlights: Five-star Jamshedpur thrash table-toppers Bengaluru
Catch all the Live updates from the Indian Super League match between Bengaluru FC and Jamshedpur FC
FP Sports February 27, 2019 19:37:59 IST
Bengaluru FC would look test their bench strength when they take on Jamshedpur FC in their final league game of the Indian Super League.
Bengaluru are currently leading the table with 34 points from 17 games and were the first team to qualify for the play-offs.
But it would easier said than done as Bengaluru have won only two of their last six matches.
Click here to follow all the live action between Jamshedpur FC and Bengaluru FC.
Preview: Already through to the play-offs, Bengaluru FC would look test their bench strength when they take on Jamshedpur FC in their final league game of the Indian Super League on Wednesday.
But the form of Carles Cuadrat's side since the international break has been a concern. They, however, got their confidence back after a 3-0 win over FC Goa in the previous game and will now seek to finish the league stage on a positive note.
The Blues have faced Jamshedpur three times and both teams have a win each. Their last meeting ended in a thrilling 2-2 draw in October, with Sergio Cidoncha netting a late equaliser in added time.
"We have a lot of people who have stayed back in Bengaluru. We are coming here with a mix of players. We are going to start four players in the starting XI who have played most of the season with the second team (BFC B)," Bengaluru coach Cuadrat said.
Cuadrat, who will be hoping to end Bengaluru's winless run away from home after three losses and a draw in their last four trips, said three second-team players will also start on the bench.
"We have the privilege because we are for sure going to finish first in the league. We are not fighting for second or third anymore. We have left some players to save them travel and avoid injuries. It's a chance for us to give the fringe players an opportunity," he said.
Jamshedpur have had a season full of mixed results and have played nine draws this season, the highest tally for a club in the league stage in ISL.
After a shocking 1-4 defeat against FC Pune, they were held by Chennaiyin in their last match, a result that crushed their hopes of qualifying.
"Like the top four teams, we did not have a striker scoring consistently but most of our goals were shared between our attackers. The lack of finishing is perhaps why we have had so many draws. Of course, missing out on the top-four is a disappointment," said coach Cesar Ferrando.
With play-off spot no longer available, Jamshedpur would look to pocket a morale boosting win.
"It's the last game in front of our home fans and we want to win it for them. I am delighted with the performance of the team and I wish we can finish the season on a high with a win against Bengaluru," said the coach.
For the full Indian Super League schedule, click here
For all the results from this Indian Super League season, click here
For the Indian Super League points table, click here
With inputs from PTI
Updated Date: February 27, 2019 23:04:09 IST
Carles Cuadrat
Cesar Ferrando
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text:
You can style the navigator appearance and behavior by passing a `navigatorStyle` object. This object can be passed when the screen is originally created; can be defined per-screen by setting `static navigatorStyle = {};` on the screen component; and can be overridden when a screen is pushed.

The easiest way to style your screen is by adding `static navigatorStyle = {};` to your screen React component definition.

```js
export default class StyledScreen extends Component {
  static navigatorStyle = {
    drawUnderNavBar: true,
    navBarTranslucent: true
  };
  constructor(props) {
    super(props);
  }
  render() {
    return (
      <View style={{flex: 1}}>...</View>
     );
  }
```

## Setting styles dynamically
Use the `setStyle` method to change a screen's style dynamically.

```js
this.props.navigator.setStyle({
  navBarBackgroundColor: 'blue'
});
```

## Style object format

```js
{
  // Common
  navBarTextColor: '#000000', // change the text color of the title (remembered across pushes)
  navBarTextFontFamily: 'font-name', // Changes the title font
  navBarBackgroundColor: '#f7f7f7', // change the background color of the nav bar (remembered across pushes)

  navBarButtonColor: '#007aff', // Change color of nav bar buttons (eg. the back button) (remembered across pushes)

  navBarHidden: false, // make the nav bar hidden
  navBarHideOnScroll: false, // make the nav bar hidden only after the user starts to scroll
  navBarTranslucent: false, // make the nav bar semi-translucent, works best with drawUnderNavBar:true
  navBarTransparent: false, // make the nav bar transparent, works best with drawUnderNavBar:true,
  navBarNoBorder: false, // hide the navigation bar bottom border (hair line). Default false
  drawUnderNavBar: false, // draw the screen content under the nav bar, works best with navBarTranslucent:true
  drawUnderTabBar: false, // draw the screen content under the tab bar (the tab bar is always translucent)
  statusBarBlur: false, // blur the area under the status bar, works best with navBarHidden:true
  navBarBlur: false, // blur the entire nav bar, works best with drawUnderNavBar:true
  tabBarHidden: false, // make the screen content hide the tab bar (remembered across pushes)
  statusBarHideWithNavBar: false // hide the status bar if the nav bar is also hidden, useful for navBarHidden:true
  statusBarHidden: false, // make the status bar hidden regardless of nav bar state
  statusBarTextColorScheme: 'dark', // text color of status bar, 'dark' / 'light' (remembered across pushes)
  statusBarTextColorSchemeSingleScreen: 'light' // same as statusBarTextColorScheme but does NOT remember across pushes
  navBarSubtitleColor: 'red', // subtitle color
  screenBackgroundColor: 'white', // Default screen color, visible before the actual react view is rendered
  orientation: 'portrait' // Sets a specific orientation to a modal and all screens pushed to it. Default: 'auto'. Supported values: 'auto', 'landscape', 'portrait'

  // iOS only
  disabledBackGesture: false, // default: false. Disable the back gesture (swipe gesture) in order to pop the top screen.
  screenBackgroundImageName: '<name of image in Images.xcassets>', // Optional. default screen background image.

  navBarButtonFontSize: 20, // Change font size nav bar buttons (eg. the back button) (remembered across pushes)
  navBarButtonFontWeight: '500', // Change font weight nav bar buttons (eg. the back button) (remembered across pushes)

  navBarLeftButtonFontSize: 17, // Change font size of left nav bar button
  navBarLeftButtonColor: 'red', // Change color of left nav bar button
  navBarLeftButtonFontWeight: '400', // Change font weight of left nav bar button

  navBarRightButtonFontSize: 17, // Change font size of right nav bar button
  navBarRightButtonColor: 'blue', // Change color of right nav bar button
  navBarRightButtonFontWeight: '600', // Change font weight of right nav bar button

  // Android only
  navigationBarColor: '#000000', // change the background color of the bottom native navigation bar.
  navBarTitleTextCentered: true, // default: false. centers the title.
  topBarElevationShadowEnabled: false, // default: true. Disables TopBar elevation shadow on Lolipop and above
  statusBarColor: '#000000', // change the color of the status bar.
  collapsingToolBarImage: "http://lorempixel.com/400/200/", // Collapsing Toolbar image.
  collapsingToolBarImage: require('../../img/topbar.jpg'), // Collapsing Toolbar image. Either use a url or require a local image.
  collapsingToolBarCollapsedColor: '#0f2362', // Collapsing Toolbar scrim color.
}
```

## Styling the StatusBar
If you set any styles related to the Status Bar, make sure that in Xcode > project > Info.plist, the property `View controller-based status bar appearance` is set to `YES`.

## Custom fonts
If you'd like to use a custom font, you'll first have to your project.

* Android - add the `.ttf` or `.otf` files to `src/main/assets/fonts/`

* iOS - follow this [guide](https://medium.com/@dabit3/adding-custom-fonts-to-react-native-b266b41bff7f)

All supported styles are defined [here](https://github.com/wix/react-native-controllers#styling-navigation). There's also an example project there showcasing all the different styles.


Below you will find our top resources to help you learn more about LoRa Technology or bring a LoRa-based solution to market.
Explore our growing library of videos about LoRa Technology use cases, video interviews, instructional videos, and features from our partners.
Dig deeper into LoRa Technology by downloading white papers from the LoRa white paper library. Find technical content, case studies, thorough use cases, and content from our partners, like Comcast's machineQ.
The LoRa Developer Portal is a premier user community platform for Internet of Things (IoT) and machine-to-machine (M2M) technologists, developers, end users, and solution providers to connect, learn and share LoRa Technology information. The portal is the number one source for LoRa technical support.
The LoRaWAN Academy is an all-encompassing, hands-on curriculum for developers, enterprises, students, or universities to learn about the LoRaWAN open specification. The free program features a robust online course library.
Semtech is showcasing LoRaWAN technology in Digital Catapult's new Future Networks Lab in central London, helping to unlock value for industry/government/small businesses by enabling collaboration, experimentation and demonstration of the potential of exciting technologies at scale. We are accelerating the use of future networks technologies such as 5G, LPWAN and IoT, providing access to experimental testbeds and trial networks to try out new and risky ideas in a safe and measurable environment. To find out more about the technology showcase and how to book the Future Networks Lab, visit Digital Catapult's website.
Refer to the LoRa brand guidelines for comprehensive guidance on LoRa mark and logo use.