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Top of the crops: rice scientists seek to meet global food demands
In vivo and in vitro spermatogenesis in prepubertal mouse testes exposed to low gonadotoxic doses of cytarabine or Daunorubicin
Defend scientific integrity and academic freedom
Relationship of the lumbar Lordotic angle to the abdominal aortic deviation and abdominal aortic diameter
Small parallel residual convolutional neural network and traffic congestion detection
Research on rolling bearing compound fault diagnosis based on AMOMCKD and convolutional neural network
Europe must become a research epicentre as US system gets undermined
Characterization of talc deposits in ultramafic rocks of Gebel El Maiyit and its economic feasibility
Abstract A comprehensive, multiscale investigation, integrating remote sensing, mineralogy, whole rock chemistry, Electron Microprobe (EMP), and stable isotopes (oxygen-18O and carbon-13C), was undertaken to assess the feasibility of talc deposits and their host serpentinite at Gebel El-Maiyit in the Eastern Desert of Egypt. Sentinel 2 remote sensing images were applied to discriminate talc from serpentinites followed by geochemical study of serpentinites using RO`/SiO2 ratios, AFM diagram and MgO versus SiO2 relationship indicates a peridotite origin formed at low temperature Alpine type. Our study revealed that talc deposit has a varied mineralogical composition and according to the predominant talc and gangue minerals three main types have been distinguished: 1- pure talc, 2- tremolite talc and 3- chlorite talc. Paragenetically, talc is derived from serpentine minerals, tremolite and chlorite. The latter is formed at about 231 °C. The chemical data of talc deposit reveals that the summation of talc components (SiO2 + MgO + H2O) is 92.68%, while that of impurity oxides (Al2O3 + CaO + Fe2O3 + FeO) is 5.56%. The carbon13C) and oxygen18O) contents of pure magnesite revealed that the pure phase of Gebel El-Maiyit was formed at low temperature (around 100 °C) while magnesite contained in talc carbonate rock was formed at high temperature (140–175 °C). In terms of source fluids, the metamorphic and /or magmatic water was supposed to be the main fluids which are circulated during the hydrothermal alteration. Although S and P are very minor components in all the talc ore types of the considered area and do not affect their industrial use. Copper (Cu) was not detected. Iron (Fe) and manganese (Mn) concentrations are significantly high, necessitating treatment to reduce these elements for the ore to be suitable as an electrical insulator. Arsenic (As) levels are consistently below 5 ppm, indicating the ore’s potential use in the cosmetic industry without further processing.
How India rewrote the rules of space travel when it launched its first satellite
A comprehensive study of recent maximum power point tracking techniques for photovoltaic systems
Abstract The percentage of renewable energy in the global mix of energy sources is rising annually, with solar photovoltaics (PVs) accounting for most capacity expansions due to their widespread availability, safety, and cleanliness. Because the amount of energy generated is limited by the poor efficiency of the photovoltaic cells and the characteristics of the connected load and weather fluctuation, maximum power point tracking (MPPT) strategies are crucial for maximizing the power delivered in PV production systems. These MPPT techniques face several issues and limitations, so this paper has focused more on modeling and developing the MPPT techniques in PV systems. The MPPT-based methodologies fall into three categories: artificial intelligence (AI), metaheuristic, and conventional. Five of these techniques have been proposed here to solve the MPPT problem. The perturb & observe (P&O) and incremental conductance (INC) methods have been used as conventional methods. In contrast, particle swarm optimization (PSO) has been used as a metaheuristic method. Finally, the artificial neural network (ANN) and fuzzy logic control (FLC) techniques have been used as AI methods. Each technique is analyzed critically in terms of tracking speed, algorithm complexity, and dynamic tracking in different environmental conditions. Furthermore, this comprehensive study of MPPT methods aims to be a guideline for selecting the best MPPT method for optimal operation under the environmental conditions of PV systems by employing multi-criteria decision-making (MCDM) based on AHP and CRITIC weighting methods, as well as the ranking method (VIKOR), to compare and rank the MPPT methods based on their effectiveness and economic feasibility. The results show AI techniques have a tracking efficiency of almost 99% when compared to other examined approaches, and they give quick and efficient tracking speed.
Enhancing stochastic optimal power flow with modified cheetah optimizer for integrating renewable energy sources
Quantifying soil wind erosion attribution in Inner Mongolia’s desert grassland
The clinical and genetic spectrum of twenty-six individuals with hearing loss affected by MYO15A variants
Long-term cardiovascular risk and mortality associated with uric acid to HDL-C ratio: a 20-year cohort study in adults over 40
Why politicians manipulate statistics — and what to do about it
Integrin linked kinase and threonine tyrosine kinase modulate TCR signaling
Abstract T cell activation is critical for adaptive immunity, helping to protect the body from infection and tumors. A key step in this activation is signal transduction downstream of the T cell antigen receptor. This signaling involves several steps, with early ones occurring at the plasma membrane and others that occur later, after TCR internalization. The late steps in TCR signaling remain poorly understood. Since the TCR can signal after its internalization, we postulated that kinases abundantly expressed in T cells may regulate TCR signaling. This study focuses on two such enzymes: integrin-linked kinase (ILKs) and threonine-tyrosine kinase (TTKs), whose involvement in TCR signaling has not been previously studied. Using specific depletion of TTK and ILK by lentiviral shRNA, we show that in the absence of ILK and TTK, the early steps of TCR signaling are strongly enhanced, while IL-2 production by activated T cells is strongly decreased. These findings are relevant because TTK and ILK are both important targets in oncology, and our results show that their inhibition affects the activation of T cells, which play an essential role in anti-tumor defense.