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The effect of nanoparticles on the structure and enzymatic activity of human carbonic anhydrase I and II

Human carbonic anhydrases (hCAs) belong to a well characterized group of metalloenzymes that catalyze the conversion of carbonic dioxide into bicarbonate. There are currently 15 known human isoforms of carbonic anhydrase with different functions and distribution in the body. This links to the relevance of hCA variants to several diseases such as glaucoma, epilepsy, mountain sickness, ulcers, osteo

Why do some sex chromosomes degenerate more slowly than others? The odd case of ratite sex chromosomes

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

Electroweak corrections to the angular coefficients in finite- pT Z-boson production and dilepton decay

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

Long Non-coding RNA T-UCstem1 Controls Progenitor Proliferation and Neurogenesis in the Postnatal Mouse Olfactory Bulb through Interaction with miR-9

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

Lymphocyte antigen 6 superfamily member D is a marker of urothelial and squamous differentiation : Implications for risk stratification of bladder cancer

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

Causal relationships between body mass index, smoking and lung cancer : Univariable and multivariable Mendelian randomization

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

Highly-ordered ultrathin films of quaterthiophene on a Ag (111) surface

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

Orientation and bonding of thiophene and 2,2′-bithiophene on Ag(111) : a combined near edge extended X-ray absorption fine structure and Xα scattered-wave study

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

Near edge X-ray absorption fine structure resonances of quinoide molecules

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

EXAFS investigations on highly-ordered ultrathin films of Me-DCNQI on single crystal surfaces

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

Stem Cells, Cell Therapies, and Bioengineering in Lung Biology and Disease 2019

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

New insight in the optical properties of ultrathin oligothiophene films by epitaxial preparation

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

New insight into the optical properties of thin organic films by epitaxial preparation

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

High-resolution luminescence of epitaxial organic films : Quaterthiophene on Ag (111)

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,

NEXAFS investigations of highly-ordered ultrathin films of DME-DCNQI on Ag (111)

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

Adsorption-induced bending of a triatomic molecule : Near-edge X-ray absorption fine-structure spectroscopy investigation of N2O adsorbed on different Ni(111) surfaces

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

Adsorption geometry of OH adsorbed at F centers on a NaCl(100) surface

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

Reaching for the Mountains at the End of a Rebelocracy: Changes in Land and Water Access in Colombia's Highlands During the Post-peace Agreement Phase

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