Physical Mechanism of the d->d+is Transition

We discuss the basic physical mechanism of the d->d+is transition, which is the currently accepted explanation for the results of tunneling experiments into $ab$ planes. Using the first-order perturbation theory, we show that the zero-bias states drive the transition. We present various order-of-magnitude estimates and consistency checks that support this picture.Comment: 7 pages, 2 figure

General properties and analytical approximations of photorefractive solitons

We investigate general properties of spatial 1-dimensional bright photorefractive solitons and suggest various analytical approximations for the soliton profile and the half width, both depending on an intensity parameter r

The effective bootstrap

We study the numerical bounds obtained using a conformal-bootstrap method - advocated in ref. [1] but never implemented so far - where different points in the plane of conformal cross ratios z and z¯ are sampled. In contrast to the most used method based on derivatives evaluated at the symmetric point z=z¯=1/2, we can consistently "integrate out" higher-dimensional operators and get a reduced simpler, and faster to solve, set of bootstrap equations. We test this "effective" bootstrap by studying the 3D Ising and O(n) vector models and bounds on generic 4D CFTs, for which extensive results are already available in the literature. We also determine the scaling dimensions of certain scalar operators in the O(n) vector models, with n=2,3,4, which have not yet been computed using bootstrap techniques. ArXI

Algorithm for obtaining the gradient expansion of the local density of states and the free energy of a superconductor

We present an efficient algorithm for obtaining the gauge-invariant gradient expansion of the local density of states and the free energy of a clean superconductor. Our method is based on a new mapping of the semiclassical linearized Gorkov equations onto a pseudo-Schroedinger equation for a three-component wave-function psi(x), where one component is directly related to the local density of states. Because psi(x) satisfies a linear equation of motion, successive terms in the gradient expansion can be obtained by simple linear iteration. Our method works equally well for real and complex order parameter, and in the presence of arbitrary external fields. We confirm a recent calculation of the fourth order correction to the free energy by Kosztin, Kos, Stone and Leggett [Phys. Rev. B 58, 9365 (1998)], who obtained a discrepancy with an earlier result by Tewordt [Z. Phys. 180, 385 (1964)]. We also give the fourth order correction to the local density of states, which has not been published before.Comment: 12 preprint pages, added remark concerning Eilenberger equation, accepted for publication in Phys. Rev.

Seasonal diet changes in elephant and impala in mopane woodland

Elephant and impala as intermediate feeders, having a mixed diet of grass and browse, respond to seasonal fluctuations of forage quality by changing their diet composition. We tested the hypotheses that (1) the decrease in forage quality is accompanied by a change in diet from more monocots in the wet season to more dicots in the dry season and that that change is more pronounced and faster in impala than in elephant; (2) mopane (Colophospermum mopane), the most abundant dicot species, is the most important species in the elephant diet in mopane woodland, whereas impala feed relatively less on mopane due to the high condensed tannin concentration; and (3) impala on nutrient-rich soils have a diet consisting of more grass and change later to diet of more browse than impala on nutrient-poor soils. The phosphorus content and in vitro digestibility of monocots decreased and the NDF content increased significantly towards the end of the wet season, whereas in dicots no significant trend could be detected. We argue that this decreasing monocot quality caused elephant and impala to consume more dicots in the dry season. Elephant changed their diet gradually over a 16-week period from 70% to 25% monocots, whereas impala changed diets rapidly (2-4 weeks) from 95% to 70% monocots. For both elephants and impala, there was a positive correlation between percentage of monocots and dicots in the diet and the in vitro digestibility of these forage items. Mopane was the most important dicot species in the elephant diet and its contribution to the diet increased significantly in the dry season, whereas impala selected other dicot species. On nutrient-rich gabbroic soils, impala ate significantly more monocots than impala from nutrient-poor granitic soils, which was related to the higher in vitro digestibility of the monocots on gabbroic soil. Digestibility of food items appears to be an important determinant of diet change from the wet to the dry season in impala and elephants

Особенности и структура автоматизированного магнитотерапевтического аппарата

Розглядаються питання розробки та особливості структури автоматизованого магнітотерапевтичного апарату (АМА) з можливостями широкого керування параметрами магнітного поля (магнітної індукції, частоти, тривалості імпульсів та форми поля). Були проведені дослідження розподілення постійної та змінної складових магнітного поля в самому індукторі та комплексі «індуктор-біологічний об'єкт» в магнітотерапевтичних апаратах (МТА) «ПОЛЮС-4», «МИТ-11» та виконано їх порівняння. На основі експериментальних і теоретичних досліджень запропонований спосіб імпульсної магнітотерапії та структура автоматизованого магнітотерапевтичного апарату з точно нормованими параметрами магнітного поля та заданими параметрами впливу в робочій зоні індуктора, контролем ефективності дії фізіотерапевтичної процедури.The questions of development and feature of structure of the automated magnetotherapy apparatus (AMA) are examined with possibilities of wide management of magnetic-field (magnetic induction, frequency, duration of impulses and field form) parameters. There were undertaken studies of distribution of permanent and variable constituents of magnetic-field in an inductor and complex "inductor-biological object" in the magnetotherapy apparatus (MTA) of "POLUS-4", "MIT-11" and performed their comparison. On the basis of experimental and theoretical researches an offer method of impulsive magnetotherapy and structure of the automated magnetotherapy apparatuses are with the exactly rationed parameters of magnetic-field and preset parameter of influence in the working zone of inductor, by control of efficiency of action of physical therapy procedure. A new method and the principle of automated magnetotherapy apparatus to control output parameters: magnetic induction, frequency, form fields, pulse duration.Рассматриваются вопросы разработки и особенности структуры автоматизированного магнитотерапевтического аппарата (АМА) с возможностями широкого управления параметрами магнитного поля (магнитной индукции, частоты, длительности импульсов и формы поля). Были проведены исследования распределения постоянной и переменной составляющих магнитного поля в самом индукторе и комплексе «индуктор-биологический объект» в магнитотерапевтических аппаратах «ПОЛЮС-4», «МИТ-11» и выполнено их сравнение. На основе экспериментальных и теоретических исследований предложен способ импульсной магнитотерапии и структура автоматизированного магнитотерапевтического аппарата с точно нормированными параметрами магнитного поля и заданными параметрами воздействия в рабочей зоне индуктора, контролем эффективности действия физиотерапевтической процедуры

HP1 drives de novo 3D genome reorganization in early Drosophila embryos

Fundamental features of 3D genome organization are established de novo in the early embryo, including clustering of pericentromeric regions, the folding of chromosome arms and the segregation of chromosomes into active (A-) and inactive (B-) compartments. However, the molecular mechanisms that drive de novo organization remain unknown. Here, by combining chromosome conformation capture (Hi-C), chromatin immunoprecipitation with high-throughput sequencing (ChIP–seq), 3D DNA fluorescence in situ hybridization (3D DNA FISH) and polymer simulations, we show that heterochromatin protein 1a (HP1a) is essential for de novo 3D genome organization during Drosophila early development. The binding of HP1a at pericentromeric heterochromatin is required to establish clustering of pericentromeric regions. Moreover, HP1a binding within chromosome arms is responsible for overall chromosome folding and has an important role in the formation of B-compartment regions. However, depletion of HP1a does not affect the A-compartment, which suggests that a different molecular mechanism segregates active chromosome regions. Our work identifies HP1a as an epigenetic regulator that is involved in establishing the global structure of the genome in the early embryo

The Gradient Expansion for the Free-Energy of a Clean Superconductor

We describe a novel method for obtaining the gradient expansion for the free energy of a clean BCS superconductor. We present explicit results up to fourth order in the gradients of the order parameter.Comment: 33 pages, Late

Current Distribution and random matrix ensembles for an integrable asymmetric fragmentation process

We calculate the time-evolution of a discrete-time fragmentation process in which clusters of particles break up and reassemble and move stochastically with size-dependent rates. In the continuous-time limit the process turns into the totally asymmetric simple exclusion process (only pieces of size 1 break off a given cluster). We express the exact solution of master equation for the process in terms of a determinant which can be derived using the Bethe ansatz. From this determinant we compute the distribution of the current across an arbitrary bond which after appropriate scaling is given by the distribution of the largest eigenvalue of the Gaussian unitary ensemble of random matrices. This result confirms universality of the scaling form of the current distribution in the KPZ universality class and suggests that there is a link between integrable particle systems and random matrix ensembles.Comment: 11 page