Histochemical determination of glycosaminoglycans (GAGs) in normal and ethanol-induced chick embryo during neural tube development

Alcohol as a teratogenic agent inhibits cell growth, function, proliferation and migration by affecting macromolecules, and can induce cell death. Prenatal ethanol exposure causes neural tube defects (NTD) and growth deficiency in experimental animals. NTDs are a group of malformations that result in failure of neural tube (NT) closure in early embryonic development and are among the most common congenital malformations in humans. NTDs are also associated with a number of other central nervous system malformations. Basal layers are the most densely stained structures with Alcian blue which determines glycosaminoglycan (GAG) types. While all sulphated GAGs were observed in the basal layers of NT of the embryos in control and saline-injected groups, hyaluronic acid was dominant in the 10% alcohol-administered embryos. It was reduced in the 15% alcohol-administered embryos and keratan sulphate was significantly low in 20% samples. Especially in the control and saline-injected groups, chondroitin sulphate and dermatan sulphate were highly expressed around cells migrating from the NT, while the same were reduced in 10% alcohol-administered embryos. In 15% alcoholadministered embryos, while the heparine and heparane sulphate were dense around cells migrating from the NT, staining specificities were decreased in 20% alcohol-administered embryos in same regions. Increased alcohol degrees cause decrease of the GAG types in both areas.Key words: Neural tube development, alcohol, glycosaminoglycans (GAGs), chick

Investigation of Stem Cell Applications on In Vitro Fertilization in Rats

ΔΕΝ ΔΙΑΤΙΘΕΤΑΙ ΠΕΡΙΛΗΨΗWe aimed to search the effects of bone marrow-derived mesenchymal stem cell-conditioned media on in vitro fertilization by investigation of lifetime of germ cells cleavage, degeneration rates and embryo quality. For this purpose, firstly MSCs were isolated from femurs and tibias of the rat, and cells were cultured until the fourth passage. Sperm and oocytes were collected from male and female rats. Oocytes were added in Human Tubal Fluid Media (HTFM), Single Step Media (SSM), Alpha-MEM Media (AMM) and Bone Marrow-Derived Mesenchymal Stem Cell-Conditioned Media (CM). Thousand sperm were added into the media which including oocytes. Embryos were allowed to produce by IVF. The development of the embryos was followed until the 11th day, and the arrest, degeneration rates and alive embryos were established. The embryos reached 2, 4, 8, 16 cells stages and morula stage in the CM. While AMM had a negative effect on fertilization and embryo development, the most favourable effect was shown to be caused by CM in comparison with the other medias. These results have shown that the beneficial effects of CM in IVF would be a significant increase in the rate of fertility and development of embryos

A Proof Assistant Based Formalisation of a Subset of Sequential Core Erlang

We present a proof-assistant-based formalisation of a subset of Erlang, intended to serve as a base for proving refactorings correct. After discussing how we reused concepts from related work, we show the syntax and semantics of our formal description, including the abstractions involved (e.g. the concept of a closure). We also present essential properties of the formalisation (e.g. determinism) along with the summary of their machine-checked proofs. Finally, we prove expression pattern equivalences which can be interpreted as simple local refactorings

Temperature-dependent profile of the surface states and series resistance in (Ni/Au)/ AIGaN/AIN/GaN heterostructures

The profile of the interface state densities(N ss) and series resistances (R s) effect on capacitance-voltage (C-V) and conductancevoltage (G/ω-V) of (Ni/Au)/Al xGa 1-xN/AIN/ GaN heterostructures as a function of the temperature have been investigated at 1 MHz. The admittance method allows us to obtain the parameters characterizing the metal/semiconductor interface phenomena as well as the bulk phenomena. The method revealed that the density of interface states decreases with increasing temperature. Such a behavior of N ss can be attributed to reordering and restructure of surface charges. The value of series R s decreases with decreasing temperature. This behavior of R s is in obvious disagreement with that reported in the literature. It is found that the N ss and R s of the structure are important parameters that strongly influence the electrical parameters of (Ni/Au)/Al xGa 1-XN/AlN/GaN(x = 0.22) heterostructures. In addition, in the forward bias region a negative contribution to the capacitance C has been observed, that decreases with the increasing temperature. Copyright © 2010 John Wiley & Sons, Ltd

Intrinsic mechanical behavior of MgAgSb thermoelectric material: An ab initio study

α-MgAgSb based thermoelectric (TE) device attracts much attention for its commercial application because it shows an extremely high conversion efficiency of ∼8.5% under a temperature difference of 225 K. However, the mechanical behavior of α-MgAgSb is another serious consideration for its engineering applications. Here, we apply density functional theory (DFT) simulations to examine the intrinsic mechanical properties of all three MgAgSb phases, including elastic properties, shear-stress – shear-strain relationships, deformation and failure mechanism under ideal shear and biaxial shear conditions. We find that the ideal shear strength of α-MgAgSb is 3.25 GPa along the most plausible (100) slip system. This strength is higher than that of β-MgAgSb (0.80 GPa) and lower than that of γ-MgAgSb (3.43 GPa). The failure of α-MgAgSb arises from the stretching and breakage of Mg-Sb bond α-MgAgSb under pure shear load, while it arises from the softening of Mg-Ag bond and the breakage of Ag-Sb bond under biaxial shear load. This suggests that the deformation mechanism changes significantly under different loading conditions

Non-locality in quantum field theory due to general relativity

We show that general relativity coupled to a quantum field theory generically leads to non-local effects in the matter sector. These non-local effects can be described by non-local higher dimensional operators which remarkably have an approximate shift symmetry. When applied to inflationary models, our results imply that small non-Gaussianities are a generic feature of models based on general relativity coupled to matter fields. However, these effects are too small to be observable in the cosmic microwave background

Superstrengthening Bi_2Te_3 through Nanotwinning

Bismuth telluride (Bi_2Te_3) based thermoelectric (TE) materials have been commercialized successfully as solid-state power generators, but their low mechanical strength suggests that these materials may not be reliable for long-term use in TE devices. Here we use density functional theory to show that the ideal shear strength of Bi_2Te_3 can be significantly enhanced up to 215% by imposing nanoscale twins. We reveal that the origin of the low strength in single crystalline Bi_2Te_3 is the weak van der Waals interaction between the Te1 coupling two Te1─Bi─Te2─Bi─Te1 five-layer quint substructures. However, we demonstrate here a surprising result that forming twin boundaries between the Te1 atoms of adjacent quints greatly strengthens the interaction between them, leading to a tripling of the ideal shear strength in nanotwinned Bi_2Te_3 (0.6 GPa) compared to that in the single crystalline material (0.19 GPa). This grain boundary engineering strategy opens a new pathway for designing robust Bi_2Te_3 TE semiconductors for high-performance TE devices

Hamlet-Pattern-Based Automated COVID-19 and Influenza Detection Model Using Protein Sequences.

SARS-CoV-2 and Influenza-A can present similar symptoms. Computer-aided diagnosis can help facilitate screening for the two conditions, and may be especially relevant and useful in the current COVID-19 pandemic because seasonal Influenza-A infection can still occur. We have developed a novel text-based classification model for discriminating between the two conditions using protein sequences of varying lengths. We downloaded viral protein sequences of SARS-CoV-2 and Influenza-A with varying lengths (all 100 or greater) from the NCBI database and randomly selected 16,901 SARS-CoV-2 and 19,523 Influenza-A sequences to form a two-class study dataset. We used a new feature extraction function based on a unique pattern, HamletPat, generated from the text of Shakespeare's Hamlet, and a signum function to extract local binary pattern-like bits from overlapping fixed-length (27) blocks of the protein sequences. The bits were converted to decimal map signals from which histograms were extracted and concatenated to form a final feature vector of length 1280. The iterative Chi-square function selected the 340 most discriminative features to feed to an SVM with a Gaussian kernel for classification. The model attained 99.92% and 99.87% classification accuracy rates using hold-out (75:25 split ratio) and five-fold cross-validations, respectively. The excellent performance of the lightweight, handcrafted HamletPat-based classification model suggests that it can be a valuable tool for screening protein sequences to discriminate between SARS-CoV-2 and Influenza-A infections