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The hallmark of sex chromosome evolution is the progressive suppression of recombination which leads to subsequent degeneration of the non-recombining chromosome. In birds, species belonging to the two major clades, Palaeognathae (including tinamous and flightless ratites) and Neognathae (all remaining birds), show distinctive patterns of sex chromosome degeneration. Birds are female heterogametic

We present next-to-leading order (NLO) electroweak corrections to the dominant five angular coefficients parametrizing the Drell–Yan process in the Z-boson mass peak range for finite-pT vector boson production. The results are presented differentially in the vector boson transverse momentum. The Lam–Tung violating difference A- A2 is examined alongside the coefficients. A single lepton transverse

Neural stem cell populations generate a wide spectrum of neuronal and glial cell types in a highly ordered fashion. MicroRNAs are essential regulators of this process. T-UCstem1 is a long non-coding RNA containing an ultraconserved element, and in vitro analyses in pluripotent stem cells provided evidence that it regulates the balance between proliferation and differentiation. Here we investigate

Background: Screening across a multitude of normal and malignant tissues revealed an enhanced expression of lymphocyte antigen 6 superfamily member D (LY6D) in squamous epithelium and urothelium, as well as in malignancies derived therefrom. The aim of this study was to further delineate the protein expression of LY6D in urothelial bladder cancer, with particular attention to its relationship with

At the time of cancer diagnosis, body mass index (BMI) is inversely correlated with lung cancer risk, which may reflect reverse causality and confounding due to smoking behavior. We used two-sample univariable and multivariable Mendelian randomization (MR) to estimate causal relationships of BMI and smoking behaviors on lung cancer and histological subtypes based on an aggregated genome-wide assoc

Ultrathin films of quaterthiophene (4T) were deposited on a Ag(111) surface by vacuum sublimation and characterized with respect to their geometric and electronic properties using several surface-sensitive techniques. For the monolayer (1 ML), a long-range ordered superstructure is found by electron diffraction (LEED). This is commensurate to the Ag(111) surface due to covalent bonding of the "fla

The adsorption of thiophene and 2,2′-bithiophene on Ag(111) was studied using temperature programmed desorption and near-edge X-ray-absorption fine-structure (NEXAFS). The assignment of the NEXAFS resonances is supported by Xα scattered-wave calculations. For thiophene we identify a compressed and a relaxed monolayer species. Whereas the molecules in the latter state are adsorbed parallel to the s

We report on C 1s and N 1s near-edge X-ray absorption (NEXAFS) investigations of highly oriented ultrathin films of 2,5-dimethyl-N,N′-dicyanoquinonediimine (DMe-DCNQI), tetracyano-quinonedimethane (TCNQ), and 2,5-dimethyl-1,4-benzoquinone (DMe-BQ) adsorbed on Ag(111). Several sharp resonances are resolved in the spectra indicating the localized electronic structure of these quinoide molecules. The

DMe-DCNQI forms highly-ordered ultrathin films on various single crystal surfaces. NEXAFS reveals flat lying molecules for all investigated film thicknesses (up to 40 layers) on nearly all substrates under investigation (Ag(111), Ag(100), Cu(100), Cu(111)). The C1s and N1s NEXAFS spectra of these condensed layers show several very sharp resonances. The comparison with the quinoide molecules TCNQ a

A workshop entitled "Stem Cells, Cell Therapies and Bioengineering in Lung Biology and Diseases" was hosted by the University of Vermont Larner College of Medicine in collaboration with the National Heart, Lung and Blood Institute, the Alpha-1 Foundation, the Cystic Fibrosis Foundation, the International Society for Cell and Gene Therapy and the Pulmonary Fibrosis Foundation. The event was held fr

Interesting optical properties are obtained if highly ordered interfaces and thin films of large organic molecules are prepared on an atomically flat and clean substrate. Then the optical spectra are very different from those of conventional films and reveal a variety of finestructures. On the basis of one example, quaterthiophene on Ag(111), it is demonstrated that long-range ordered monolayers w

On the basis of the example of quaterthiophene (4T) on a Ag(111) surface, we demonstrate that epitaxial thin films can be prepared on a single crystalline substrate under suitable conditions. Optical spectra of such 4T films exhibit a highly resolved fine structure similar to that of isolated molecules. The detailed spectroscopic information thus obtained yields new insight into questions such as

Thin films (less than 40 Å) of quaterthiophene (4T) were vapour deposited onto a Ag(111) surface under ultrahigh vacuum (UHV) and were investigated concerning their geometrical structure and photoluminescence (PL) properties by low-energy electron diffraction (LEED) and optical spectroscopy, respectively. Two different structural phases (α and β) were observed, which exhibit high structural order,

Ultrathin layers of 2,5-dimethyl-N,N′-dicyanoquinonediimine (DMe-DCNQI) have been grown on a Ag (111) surface by vapour deposition in ultrahigh vacuum. The films have been characterized by near-edge X-ray absorption fine structure (NEXAFS), low-energy electron diffraction (LEED), Thermal desorption measurements and X-ray photoelectron spectroscopy to study orientation, lateral order, interface bon

A monolayer of N2O/Ni(111), a submonolayer species, and a monolayer of N2O/Ni\(111\)+O p[2×2] were studied using near-edge x-ray absorption fine-structure spectroscopy. From the polarization dependence we derive bent N2O molecules for the monolayer species whereas the two other species remain linear upon adsorption. Using the Xα-scattered-wave method the polarization dependence of the three π* res

The orientation of molecular (Formula presented)O in a bilayer on defect-free NaCl(100) and of chemisorbed OH adsorbed at F centers on the (100) surface of NaCl was investigated using angle-resolved O K edge near-edge x-ray-absorption fine-structure spectroscopy (NEXAFS). High-quality single crystalline thin films of NaCl(100) of about four monolayers thickness were grown on Ge(100). These films w

The armed conflict shaped and determined land-uses, water access and social and environmental norms in highlands regions in Colombia for several decades. The withdrawal of the Revolutionary Armed Forces of Colombia (FARC) after the Peace Agreement with the government of Colombia in 2016, has brought new dynamics in access and uses of land leading to increasingly visible social-environmental impact

The Amazon rainforests and their biological diversity are being lost rapidly by the onslaught of extractive industries, large-scale agriculture and infrastructure development, which also undermines the integrity of indigenous territories and ethnicities, threatening the tremendous cultural diversity of the Amazon. The loss of forest, the disintegration of local communities and the increase of the