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41.
Be-doped TlBa2(Ca2−yBey)Cu3O10−δ (y=0, 0.25, 0.5, 0.75, and 1.0) superconductor bulk samples were synthesized by solid state reaction and characterized by X-ray diffraction (XRD), dc-resistivity {ρ (Ω cm)}, and Fourier Transform Infrared (FTIR) absorption spectroscopy. Fluctuations induced conductivity (FIC) analysis is carried out on temperature dependent dc-resistivity data of as-prepared and oxygen post-annealed TlBa2(Ca2−yBey)Cu3O10−δ superconductor samples by using Aslamazov–Larkin (AL) and Lawrence–Doniach (LD) models for excess conductivity. Different microscopic parameters such as zero temperature coherence length along c-axis {ξc(0)}, inter-layer coupling (J), inter-grain coupling (α), critical exponent (λD) and dimensionality of fluctuations are calculated for understanding the role of Be-doping on superconducting properties of TlBa2(Ca2−yBey)Cu3O10−δ samples. The cross-over temperature (To) is shifted towards higher temperature values with the increase of Be contents in TlBa2(Ca2−yBey)Cu3O10−δ samples. The increase in ξc(0) and J after Be-doping at Ca sites shows the improvement of inter-plane coupling in TlBa2(Ca2−yBey)Cu3O10−δ samples. The increase in zero resistivity critical temperature {Tc(R=0) (K)} up to y=0.5 and then decrease for y=0.75, 1.00 fixed the Be-doping level for optimum increase of superconducting properties of TlBa2(Ca2−yBey)Cu3O10−δ samples. The appreciable changes in all the microscopic parameters extracted from the FIC analysis and the increase in relative intensity of almost all the oxygen phonon modes indicate the oxygen diffusion in the unit cell after oxygen post-annealing the samples. The oxygen diffusion can take place at both inter-granular and intra-granular sites, which increase the superconducting volume fraction by improving the grains size, inter-grain connectivity and carrier density.  相似文献   
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The present investigation is concerned with the peristaltic flow of an incompressible and magnetohydrodynamic MHD third order fluid in an inclined asymmetric channel. Both thermal and velocity slip conditions have been taken into account. The channel walls are maintained at different temperatures. The governing differential systems subjected to their boundary conditions have been solved for small Deborah number. In the derived solution expressions, the long wavelength and low Reynolds number assumptions are utilized. Graphical results are presented for the pressure rise, longitudinal velocity and temperature. Comparison with the previous published work regarding viscous fluid and no-slip case is performed. Pumping and trapping phenomena are displayed graphically just to examine the various interesting aspects of the present work.  相似文献   
44.
This article deals with the variable MHD effects on the peristaltic flow of a non‐Newtonian fluid in the presence of heat and mass transfer. The walls of annulus are maintained at different temperatures. Continuity, momentum concentration, and energy equations are utilized in the mathematical analysis. Two types of solutions, namely, the exact and numerical, are derived. These solutions are compared and discussed. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/htj.20314  相似文献   
45.
Piwi-interacting Ribonucleic acids (piRNAs) molecule is a well-known subclass of small non-coding RNA molecules that are mainly responsible for maintaining genome integrity, regulating gene expression, and germline stem cell maintenance by suppressing transposon elements. The piRNAs molecule can be used for the diagnosis of multiple tumor types and drug development. Due to the vital roles of the piRNA in computational biology, the identification of piRNAs has become an important area of research in computational biology. This paper proposes a two-layer predictor to improve the prediction of piRNAs and their function using deep learning methods. The proposed model applies various feature extraction methods to consider both structure information and physicochemical properties of the biological sequences during the feature extraction process. The outcome of the proposed model is extensively evaluated using the k-fold cross-validation method. The evaluation result shows that the proposed predictor performed better than the existing models with accuracy improvement of 7.59% and 2.81% at layer I and layer II respectively. It is anticipated that the proposed model could be a beneficial tool for cancer diagnosis and precision medicine.  相似文献   
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47.

Scope

The effects of diet cycling on cognition and fecal microbiota are not well understood.

Method and Results

Adult male Sprague-Dawley rats were cycled between a high-fat, high-sugar “cafeteria” diet (Caf) and regular chow. The impairment in place recognition memory produced by 16 days of Caf diet was reduced by switching to chow for 11 but not 4 days. Next, rats received 16 days of Caf diet in 2, 4, 8, or 16-day cycles, each separated by 4-day chow cycles. Place recognition memory declined from baseline in all groups and was impaired in the 16- versus 2-day group. Finally, rats received 24 days of Caf diet continuously or in 3-day cycles separated by 2- or 4-day chow cycles. Any Caf diet access impaired cognition and increased adiposity relative to controls, without altering hippocampal gene expression. Place recognition and adiposity were the strongest predictors of global microbiota composition. Overall, diets with higher Caf > chow ratios produced greater spatial memory impairments and larger shifts in gut microbiota species richness and beta diversity.

Conclusion

Results suggest that diet-induced cognitive deficits worsen in proportion to unhealthy diet exposure, and that shifting to a healthy chow for at least a week is required for recovery under the conditions tested here.  相似文献   
48.
Cloud computing is one of the most attractive and cost-saving models, which provides online services to end-users. Cloud computing allows the user to access data directly from any node. But nowadays, cloud security is one of the biggest issues that arise. Different types of malware are wreaking havoc on the clouds. Attacks on the cloud server are happening from both internal and external sides. This paper has developed a tool to prevent the cloud server from spamming attacks. When an attacker attempts to use different spamming techniques on a cloud server, the attacker will be intercepted through two effective techniques: Cloudflare and K-nearest neighbors (KNN) classification. Cloudflare will block those IP addresses that the attacker will use and prevent spamming attacks. However, the KNN classifiers will determine which area the spammer belongs to. At the end of the article, various prevention techniques for securing cloud servers will be discussed, a comparison will be made with different papers, a conclusion will be drawn based on different results.  相似文献   
49.
In this article, a ternary WO3/g‐C3N4@ BiVO4 composites were prepared using eco‐friendly hydrothermal method to produce efficient hydrogen energy through water in the presence of sacrificial agents. The prepared samples were characterized by scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), transmission electron microscopy (TEM), X‐ray diffraction (XRD), ultraviolet‐visible (UV‐vis), Brunauer‐Emmett‐Teller (BET) surface area, and photoluminescence spectroscopy (PL) emission spectroscopy. The experimental study envisages the formation of 2‐D nanostructures and observed that such kinds of nanostructures could provide more active sites for photocatalytic reduction of water and their inherent reactive‐species mechanism. The results showed the excellent photocatalytic performance (432 μmol h?1 g?1) for 1.5% BiVO4 nanoparticles in WO3/g‐C3N4 composite when compared with pure WO3 and BiVO4. The optical properties and photocatalytic activity measurement confirmed that BiVO4 nanoparticles in WO3/g‐C3N4 photocatalyst inhibited the recombination of photogenerated electron and holes and enhanced the reduction reactions for H2 production. The enhanced photocatalytic efficiency of the composite nanostructures may be attributed to wide absorption region of visible light, large surface area, and efficient separation of electrons/holes pairs owing to synergistic effects between BiVO4 and WO3/g‐C3N4. The prepared samples would be a precise optimal photocatalyst to increase their suppliers for worldwide applications especially in energy harvesting.  相似文献   
50.
A strategy for creating potent and pan-genotypic stimulator of interferon genes (STING) agonists is described. Locking a bioactive U-shaped conformation of cyclic dinucleotides by introducing a transannular macrocyclic bridge between the nucleic acid bases leads to a topologically novel macrocycle-bridged STING agonist (MBSA). In addition to substantially enhanced potency, the newly designed MBSAs, exemplified by clinical candidate E7766 , exhibit broad pan-genotypic activity in all major human STING variants. E7766 is shown to have potent antitumor activity with long lasting immune memory response in a mouse liver metastatic tumor model. Two complementary stereoselective synthetic routes to E7766 are also described.  相似文献   
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