Role of CD4+ T Cells in the Control of Viral Infections: Recent Advances and Open Questions

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.     

aiTPR: Attribute Interaction-Tensor Product Representation for Image Caption

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...     

Delayed self-regulation and time-dependent chemical drive leads to novel states in epigenetic landscapes

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.     

Effect of annealing temperature on structural and magnetic properties of Co2TiO4 ceramics prepared by sol-gel method

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.     

Ideas generated in conceptual design and their effects on creativity

Search of design spaces to generate solutions affects the design outcomes during conceptual design. This research aims to understand the different types of search that occurs during conceptual design and their effect on the design outcomes. Additionally, we study the effect of other factors, such as creativity, problem-solving style, and experience of designers, on the design outcomes. Two sets of design experiments, with experienced and novice designers, are used in this study. We find that designers employ twelve different types of searches during conceptual design for problem understanding, solution generation, and solution evaluation activities. Results also suggest that creativity is influenced positively by the type and amount of searches, duration of designing, and experience of designers.     

Prediction of Phase Split in Horizontal T‐Junctions: Revisited

The prediction of liquid–liquid two‐phase flow at a horizontal dividing T‐junction is re‐investigated, focusing on a stratified orientation of the liquids. Kerosene (as oil) and water as the test fluids of previous studies are used to predict the distribution of oil and water in a 0.025‐m diameter pipe and tee. In addition to the previously studied models, attempts are made to predict the split for liquid–liquid systems by the already known energy minimization. The earlier model, formulated from geometrical considerations and force balance resulting from centripetal as well as inertial forces, is refurbished by the addition of energy minimization for the calculation of phase depth.     

Effect of Starting As-cast Structure on the Microstructure–Texture Evolution During Subsequent Processing and Finally Ridging Behavior of Ferritic Stainless Steel

Metallurgical and Materials Transactions A - Effect of the initial as-cast structure on the microstructure–texture evolution during thermomechanical processing of 409L grade ferritic...     

Intermetallic Precipitation in Low-Density Steel

Metallurgical and Materials Transactions A - Low-density steels (LDS) represent a relatively new class of material that contains a large concentration of aluminum. In the present work, we studied...