Amphibia, Anura, Hylidae, <i>Dendropsophus ruschii</i> (Weygoldt & Peixoto, 1987): Rediscovery of Ruschi’s treefrog in an Atlantic Rainforest remnant in Espírito Santo, Brazil

Non

Probing superconductivity in MgB2 confined to magnetic field tuned cylinders by means of critical fluctuations

We report and analyze reversible magnetization measurements on a high quality MgB2 single crystal in the vicinity of the zero field transition temperature, T_c=38.83 K, at several magnetic fields up to 300 Oe, applied along the c-axis. Though MgB2 is a two gap superconductor our scaling analysis uncovers remarkable consistency with 3D-xy critical behavior, revealing that close to criticality the order parameter is a single complex scalar as in 4He. This opens up the window onto the exploration of the magnetic field induced finite size effect, whereupon the correlation length transverse to the applied magnetic field H_i applied along the i-axis cannot grow beyond the limiting magnetic length L_Hi, related to the average distance between vortex lines. We find unambiguous evidence for this finite size effect. It implies that in type II superconductors, such as MgB2, there is the 3D to 1D crossover line H_pi and xi denotes the critical amplitudes of the correlation lengths above and below T_c along the respective axis. Consequently, above H_pi(T) and T<T_c superconductivity is confined to cylinders with diameter L_Hi (1D). In contrast, above T_c the uncondensed pairs are confined to cylinders. Accordingly, there is no continuous phase transition in the (H,T)-plane along the H_c2-lines as predicted by the mean-field treatment

Transcribed ultraconserved noncoding RNAs (T-UCR) are involved in Barrett's esophagus carcinogenesis.

Barretts esophagus (BE) involves a metaplastic replacement of native esophageal squamous epithelium (Sq) by columnar-intestinalized mucosa, and it is the main risk factor for Barrett-related adenocarcinoma (BAc). Ultra-conserved regions (UCRs) are a class non-coding sequences that are conserved in humans, mice and rats. More than 90% of UCRs are transcribed (T-UCRs) in normal tissues, and are altered at transcriptional level in tumorigenesis. To identify the T-UCR profiles that are dysregulated in Barretts mucosa transformation, microarray analysis was performed on a discovery set of 51 macro-dissected samples obtained from 14 long-segment BE patients. Results were validated in an independent series of esophageal biopsy/surgery specimens and in two murine models of Barretts esophagus (i.e. esophagogastric-duodenal anastomosis). Progression from normal to BE to adenocarcinoma was each associated with specific and mutually exclusive T-UCR signatures that included up-regulation of uc.58-, uc.202-, uc.207-, and uc.223- and down-regulation of uc.214+. A 9 T-UCR signature characterized BE versus Sq (with the down-regulation of uc.161-, uc.165-, and uc.327-, and the up-regulation of uc.153-, uc.158-, uc.206-, uc.274-, uc.472-, and uc.473-). Analogous BE-specific T-UCR profiles were shared by human and murine lesions. This study is the first demonstration of a role for T-UCRs in the transformation of Barretts mucosa

Scaling of the superfluid density in superfluid films

We study scaling of the superfluid density with respect to the film thickness by simulating the $x-y$ model on films of size $L \times L \times H$ ($L >> H$) using the cluster Monte Carlo. While periodic boundary conditions where used in the planar ($L$) directions, Dirichlet boundary conditions where used along the film thickness. We find that our results can be scaled on a universal curve by introducing an effective thickness. In the limit of large $H$ our scaling relations reduce to the conventional scaling forms. Using the same idea we find scaling in the experimental results using the same value of $\nu = 0.6705$.Comment: 4 pages, one postscript file replaced by one Latex file and 5 postscript figure

HOMEOSTASE DO CÁLCIO E MARCADORES DO METABOLISMO ÓSSEO NO HIPERTIREOIDISMO FELINO - REVISÃO

Hyperthyroidism is the most frequent endocrine disease in cats . It is a illness provokedby the excess of circulating thyroid hormones. Hyperthyroidism causes alteration in bone metabolism withpredominance of activity resorption. The evaluation of bone metabolism can be made by measuring serum andurinary markers of bone metabolism or bone mineral densitometry. Osteoblasts are responsible cells for boneformation while the osteoclasts are for resorption. In physiological situation osteoblastic and osteoclasticare in balance. Markers of bone formation express the osteoblastic activity and markers of the osseousresorption the osteoclástica activity. Markers of bone turnover are important in the diagnosis and prognostic ofmuscle-skeletal disease, as well as in the accompaniment of therapy. It is fundamental do carry on studies on theinfluence of feline hyperthyroidism on markers of bone formation and resorption in bone turnover to comprisepathophysiologic mechanism of bone alterations.O hipertireoidismo é a endocrinopatia mais freqüente em gatos velhos. É uma doençamultissistêmica provocada pelo excesso dos hormônios tireoidianos circulantes. O hipertireoidismo provocaalteração no metabolismo ósseo com predomínio da atividade de reabsorção. A avaliação do metabolismoósseo pode ser feita através da mensuração dos marcadores do metabolismo ósseo no soro ou na urina e,também, pela densitometria mineral óssea. Os osteoblastos são as células responsáveis pela formação ósseaenquanto os osteoclastos são responsáveis pela reabsorção. Em situação fisiológica as atividadesosteoblástica e osteoclástica estão em equilíbrio. Os marcadores da formação óssea representam a atividadeosteoblástica e os marcadores da reabsorção óssea representam à atividade osteoclástica. Os marcadores dometabolismo ósseo são importantes no diagnóstico e no prognóstico de doenças osteomusculares, bem comono acompanhamento da terapia destas doenças. São necessários estudos da influência do hipertireoidismofelino nos marcadores de formação e de reabsorção do metabolismo ósseo para que se possa compreender omecanismo fisiopatológico das alterações ósseas

Scaling of the specific heat in superfluid films

We study the specific heat of the $x-y$ model on lattices $L \times L \times H$ with $L \gg H$ (i.e. on lattices representing a film geometry) using the Cluster Monte--Carlo method. In the $H$--direction we apply Dirichlet boundary conditions so that the order parameter in the top and bottom layers is zero. We find that our results for the specific heat of various thickness size $H$ collapse on the same universal scaling function. The extracted scaling function of the specific heat is in good agreement with the experimentally determined universal scaling function using no free parameters.Comment: 4 pages, uuencoded compressed PostScrip

Atlantic reef fish biogeography and evolution

Copyright © 2007 The Authors.Journal compilation © 2007 Blackwell Publishing Ltd.AIM: To understand why and when areas of endemism (provinces) of the tropical Atlantic Ocean were formed, how they relate to each other, and what processes have contributed to faunal enrichment. RESULTS: Phylogenetic (proportion of sister species) and distributional (number of shared species) patterns are generally concordant with recognized biogeographical provinces in the Atlantic. The highly uneven distribution of species in certain genera appears to be related to their origin, with highest species richness in areas with the greatest phylogenetic depth. Diversity buildup in Atlantic reef fishes involved (1) diversification within each province, (2) isolation as a result of biogeographical barriers, and (3) stochastic accretion by means of dispersal between provinces. The timing of divergence events is not concordant among taxonomic groups. The three soft (non-terrestrial) inter-regional barriers (mid-Atlantic, Amazon, and Benguela) clearly act as ‘filters’ by restricting dispersal but at the same time allowing occasional crossings that apparently lead to the establishment of new populations and species. Fluctuations in the effectiveness of the filters, combined with ecological differences among provinces, apparently provide a mechanism for much of the recent diversification of reef fishes in the Atlantic

Charge transfer complex formation between organic interlayers drives light-soaking in large area perovskite solar cells

Light soaking (LS) is a well-known but poorly understood phenomenon in perovskite solar cells (PSCs) which significantly affects device efficiency and stability. LS is greatly reduced in large-area inverted PSCs when a PC61BM electron transport layer (ETL) is replaced with C60, where the ETL is commonly in contact with a thin bathocuproine (BCP) interlayer. Herein, we identify the key molecular origins of this LS effect using a combination of surface photovoltage, ambient photoemission spectroscopy, Raman spectroscopy, integrated with density functional theory simulations. We find that BCP forms a photoinduced charge-transfer (CT) complex with both C60 and PC61BM. The C60/BCP complex accelerates C60 dimer formation, leading to a favourable cascading energetic landscape for electron extraction and reduced recombination loss. In contrast, the PC61BM/BCP complex suppresses PC61BM dimer formation, meaning that PC61BM dimerisation is not the cause of LS. Instead, it is the slow light-induced formation of the PC61BM/BCP CT complex itself, and the new energetic transport levels associated with it, which cause the much slower and stronger LS effect of PC61BM based PSCs. These findings provide key understanding of photoinduced ETL/BCP interactions and their impact on the LS effect in PSCs