Baryon chiral perturbation theory transferred to hole-doped antiferromagnets on the honeycomb lattice

A systematic low-energy effective field theory for hole-doped antiferromagnets on the honeycomb lattice is constructed. The formalism is then used to investigate spiral phases in the staggered magnetization as well as the formation of two-hole bound states.Comment: Talk delivered by C.P. Hofmann at the XIII Mexican Workshop on Particles and Fields, October 19-26, 2011, Leon, Guanajuato, Mexico; 15 pages, 7 figure

Schlaf und zirkadiane Rhythmik im Alter

Zusammenfassung: Mit steigendem Alter nimmt die nächtliche Schlafkonsolidierung ab, kurze Nickerchen über den Tag nehmen zu, und die Schlafzeit verschiebt sich in frühere Stunden. Die Schlafregulation hängt von der Interaktion zwischen einem zirkadianen Schrittmacher (biologische Uhr) und dem Schlafhomöostaten (je länger die Wachphase, desto größer der Schlafdruck) ab. Wir konnten an gesunden älteren Personen zeigen, dass sich die Amplitude zirkadianer Rhythmen (z. B. die Melatonin-Sekretion) und die Tiefschlafdauer verringert. Gleichzeitig nimmt die Müdigkeit am Nachmittag zu, wie auch die Tendenz—im Gegensatz zu jüngeren Personen—am frühen Abend einzuschlafen. Da Licht der Hauptzeitgeber ist, um die biologische Uhr zu stabilisieren, brauchen ältere Menschen tagsüber und am Abend genügend Licht und sollten während des Tages keine oder nur kurze Nickerchen machen, um in der Folge den Schlaf in der Nacht zu verbesser

CO2OK: CO2 – optimierte Großküchen in Hessen - Bilanzierung und Optimierung -

Ziel des Projektes war es mit Bezug auf die allgemeinen Klimaschutzziele des Landes Hessen Grundlagen für den bisher wenig beachteten Markt der Außer-Haus-Verpflegung (AHV) zu erheben. Dafür sollte eine Treibhausgas (THG) -Bilanzierung in ausgewählten Großküchen durchgeführt werden. Basierend auf den Ergebnissen wurden Optimierungsfelder erarbeitet und aufgezeigt. Zur Gewinnung der entsprechenden Grundlagen wurden sowohl standortbezogene Bilanzierungen als auch die Berechnungen von Einzelmenüs angestrebt. Die Ergebnisse der Bilanzierung sowie die aufgezeigten Optimierungsfelder bzw. THG-Einsparpotenziale, könnten als Basis dienen für die Ausarbeitung von vertiefenden Klimaschutzzielen im Bereich der AHV im hessischen Klimaschutzplan 2025

Systematic Low-Energy Effective Field Theory for Magnons and Holes in an Antiferromagnet on the Honeycomb Lattice

Based on a symmetry analysis of the microscopic Hubbard and t-J models, a systematic low-energy effective field theory is constructed for hole-doped antiferromagnets on the honeycomb lattice. In the antiferromagnetic phase, doped holes are massive due to the spontaneous breakdown of the $SU(2)_s$ symmetry, just as nucleons in QCD pick up their mass from spontaneous chiral symmetry breaking. In the broken phase the effective action contains a single-derivative term, similar to the Shraiman-Siggia term in the square lattice case. Interestingly, an accidental continuous spatial rotation symmetry arises at leading order. As an application of the effective field theory we consider one-magnon exchange between two holes and the formation of two-hole bound states. As an unambiguous prediction of the effective theory, the wave function for the ground state of two holes bound by magnon exchange exhibits $f$-wave symmetry.Comment: 33 pages, 6 figure

Light, Health and Wellbeing: Implications from chronobiology for architectural design

Chronobiology is the science of biological rhythms, more specifically the impact of the 24-hour light-dark cycle and seasonal changes in day length on biochemistry, physiology and behaviour in living organisms. In the last 20 years, chronobiology has moved from its somewhat obscure scientific corner to a high-impact mainstream research field, notably with respect to the discovery of clock genes and peripheral oscillators – and a novel photoreceptor in the eye with specific input to the circadian system. Key discoveries in human chronobiology are related to the impact of light. Recognition of the so-called ‘biological effects of light’ by lighting manufacturers has led to interest in developing new lighting systems that integrate this knowledge. Is it time for the medical mainstream to take notice of what neuroscientists know about the body clock? And is it also time for architects to do so? These questions were explored at a symposium for architects, lighting engineers and manufacturers, initiated by Society for Light Treatment and Biological Rhythms (www. sltbr.org), in order to develop approaches to bridge the gap between these disciplines

Эвакуация населения при чрезвычайных ситуациях

В результате аварии на Чернобыльской АЭС (1986 г.) радиационное загрязнение затронуло все страны Северного полушария. На опасно загрязненных территориях оказалось более 1 млн. чел. В ряду поколений число смертельных онкологических заболеваний может составить десятки тысяч человек.As a result of the Chernobyl accident (1986), all countries of the Northern Hemisphere were affected by radiation pollution. In dangerously contaminated areas was more than 1 million people. In a number of generations, the number of deadly cancer can amount to tens of thousands of people

Transculturation: Mission and Modernity in Africa

This volume is a collection of papers dealing with cultural interaction between Europe and Africa resulting from missionary activity in Africa. The main focus is on the premises and impact of Protestant missionary work, both in Africa and in Europe, but one paper deals with similar processes in Islam

Encoding difficulty promotes postlearning changes in sleep spindle activity during napping

Learning-dependent increases in sleep spindle density have been reported during nocturnal sleep immediately after the learning session. Here, we investigated experience-dependent changes in daytime sleep EEG activity after declarative learning of unrelated word pairs. At weekly intervals, 13 young male volunteers spent three 24 h sessions in the laboratory under carefully controlled homeostatic and circadian conditions. At approximately midday, subjects performed either one of two word-pair learning tasks or a matched nonlearning control task, in a counterbalanced order. The two learning lists differed in the level of concreteness of the words used, resulting in an easier and a more difficult associative encoding condition, as confirmed by performance at immediate cued recall. Subjects were then allowed to sleep for 4 h; afterward, delayed cued recall was tested. Compared with the control condition, sleep EEG spectral activity in the low spindle frequency range and the density of low-frequency sleep spindles (11.25-13.75 Hz) were both significantly increased in the left frontal cortex after the difficult but not after the easy encoding condition. Furthermore, we found positive correlations between these EEG changes during sleep and changes in memory performance between pre-nap and post-nap recall sessions. These results indicate that, like during nocturnal sleep, daytime sleep EEG oscillations including spindle activity are modified after declarative learning of word pairs. Furthermore, we demonstrate here that the nature of the learning material is a determinant factor for sleep-related alterations after declarative learning

Технологические решения для строительства разведочной вертикальной скважины глубиной 2420 метров на газовом месторождении (Тюменская область)

Технологические решения для строительства разведочной вертикальной скважины глубиной 2420 метров на газовом месторождении (Тюменская область).Technological solutions for the construction of a vertical exploration well with a depth of 2420 meters at the gas field (Tyumen region)