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Neural Processing Letters - Region visual features enhance the generative capability of the machines based on features. However, they lack proper interaction-based attentional perceptions and end... 相似文献
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Q.S. Fu C.L. Li B. Meng C. Chakrabarti R. Zhang X.H. Chen Y.H. Li S.L. Yuan 《Ceramics International》2019,45(6):6906-6911
In this paper, polycrystalline Co2TiO4 ceramics have been synthesized using a sol-gel process followed by annealing at different temperatures. The lattice size and the average grain size of the samples increases with rise in annealing temperature. The temperature-dependent inverse paramagnetic susceptibilities recorded under zero-field-cooling condition have been fitted according to the Néel's expression for ferrimagnets. Subsequently, the molecular field constants and the corresponding exchange constants have been calculated. The fitting result shows that the magnetic interaction in the system becomes weaker as the annealing temperature rises. In addition, negative magnetization is observed during field-cooling process. The higher annealing temperature is beneficial to the growth of tetrahedral sublattice, leading to a decrease on compensation temperature. Furthermore, magnetization hysteresis loops for all the samples demonstrate the crucial role of grain size on the magnetic properties. 相似文献
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Synthesis and Biological Evaluation of Ferrocenylquinoline as a Potential Antileishmanial Agent 下载免费PDF全文
Md Yousuf Debarati Mukherjee Abhishek Pal Somaditya Dey Supratim Mandal Dr. Chiranjib Pal Dr. Susanta Adhikari 《ChemMedChem》2015,10(3):546-554
The emergence of resistance against antileishmanial drugs in current use necessitates the search for new classes of antileishmanial compounds. Herein we report the design, synthesis, and evaluation of a novel ferrocenylquinoline for activity against Leishmania donovani. 7‐Chloro‐N‐[2‐(1H‐5‐ferrocenyl‐1,2,3‐triazol‐1‐yl)ethyl]quinolin‐4‐amine ( 1 ) was generated by coupling an iron(II) ethynylferrocene species with 4‐(2‐ethylazido)amino‐7‐chloroquinoline using click chemistry. The synthesized compound 1 was tested for its antileishmanial activity using both promastigote and amastigote stages of L. donovani. Compound 1 showed promising anti‐promastigote activity, with an IC50 value of 15.26 μM and no cytotoxicity toward host splenocytes. From the battery of tests conducted in this study, it appears that this compound induces parasite death by promoting oxidative stress and depolarizing the mitochondrial membrane potential, thereby triggering apoptosis. These results suggest that ferrocenylquinoline 1 is a suitable lead for the development of new antileishmanial drugs. 相似文献
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H. D. Chalak Anupam Chakrabarti Abdul Hamid Sheikh Mohd. Ashraf Iqbal 《先进材料力学与结构力学》2015,22(11):897-907
C0 finite element model based on higher order zig-zag plate theory is used to study the stability analysis of laminated sandwich plates. The in-plane displacement field is obtained by superposing a global cubically varying displacement field on a zig-zag linearly varying displacement field with different slope in each layer. The transverse displacement assumes to have a quadratic variation within the core and constant in the faces. The conditions regarding transverse shear stress at layer interfaces and top and bottom are satisfied. Numerical examples covering different features of laminated sandwich plates are presented to illustrate the accuracy of the model. 相似文献
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CD4+ T cells orchestrate adaptive immune responses through their capacity to recruit and provide help to multiple immune effectors, in addition to exerting direct effector functions. CD4+ T cells are increasingly recognized as playing an essential role in the control of chronic viral infections. In this review, we present recent advances in understanding the nature of CD4+ T cell help provided to antiviral effectors. Drawing from our studies of natural human immunodeficiency virus (HIV) control, we then focus on the role of high-affinity T cell receptor (TCR) clonotypes in mediating antiviral CD4+ T cell responses. Last, we discuss the role of TCR affinity in determining CD4+ T cell differentiation, reviewing the at times divergent studies associating TCR signal strength to the choice of a T helper 1 (Th1) or a T follicular helper (Tfh) cell fate. 相似文献
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A Critical Grain Size Concept to Predict the Impact Transition Temperature of Ti-Microalloyed Steels
Based on the assumption that local principal stress remains the same everywhere within a ferrite grain, a critical value of
grain size can be determined for a fixed TiN particle size. When the grain size is smaller than the critical size, grain boundary
is expected to resist the propagation of a micro-crack that is initiated from a TiN particle. Using this concept, an attempt
has been made to predict the local cleavage fracture stress and 27J impact transition temperature (ITT) of different Ti-microalloyed
steels, which were subjected to (instrumented) Charpy impact testing. 相似文献
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Mithun K. Mitra Paul R. Taylor Chris J. Hutchison T. C. B. McLeish Buddhapriya Chakrabarti 《Journal of the Royal Society Interface》2014,11(100)
The epigenetic pathway of a cell as it differentiates from a stem cell state to a mature lineage-committed one has been historically understood in terms of Waddington''s landscape, consisting of hills and valleys. The smooth top and valley-strewn bottom of the hill represent their undifferentiated and differentiated states, respectively. Although mathematical ideas rooted in nonlinear dynamics and bifurcation theory have been used to quantify this picture, the importance of time delays arising from multistep chemical reactions or cellular shape transformations have been ignored so far. We argue that this feature is crucial in understanding cell differentiation and explore the role of time delay in a model of a single-gene regulatory circuit. We show that the interplay of time-dependent drive and delay introduces a new regime where the system shows sustained oscillations between the two admissible steady states. We interpret these results in the light of recent perplexing experiments on inducing the pluripotent state in mouse somatic cells. We also comment on how such an oscillatory state can provide a framework for understanding more general feedback circuits in cell development. 相似文献
10.
Modak Pranabananda Patra Sudipta Mitra Rahul Chakrabarti Debalay 《Metallurgical and Materials Transactions A》2018,49(6):2219-2234
Metallurgical and Materials Transactions A - Effect of the initial as-cast structure on the microstructure–texture evolution during thermomechanical processing of 409L grade ferritic... 相似文献