Faraday Rotation in Pulsar Magnetosphere

The magnetosphere of a pulsar is composed of relativistic plasmas streaming along the magnetic field lines and corotating with the pulsar. We study the intrinsic Faraday rotation in the pulsar magnetosphere by critically examining the wave modes and the variations of polarization properties for the circularly polarized natural modes under various assumptions about the magnetosphere plasma properties. Since it is difficult to describe analytically the Faraday rotation effect in such a plasma, we use numerical integrations to study the wave propagation effects in the corotating magnetosphere. Faraday rotation effect is identified among other propagation effects, such as wave mode coupling and the cyclotron absorption. In a highly symmetrical electron-positron pair plasma, the Faraday rotation effect is found to be negligible. Only for asymmetrical plasmas, such as the electron-ion streaming plasma, can the Faraday rotation effect become significant, and the Faraday rotation angle is found to be approximately proportional to $\lambda^{0.5}$ instead of the usual $\lambda^2$-law. For such electrons-ion plasma of pulsar magnetosphere, the induced rotation measure becomes larger at higher frequencies, and should have opposite signs for the emissions from opposite magnetic poles.Comment: 15 pages, 4 figure, submitted to MNRA

Nonlinear Response of Soil–Structure Systems using Dynamic Centrifuge Experiments

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Expanded antigen-experienced CD160+CD8+effector T cells exhibit impaired effector functions in chronic lymphocytic leukemia

Background T cell exhaustion compromises antitumor immunity, and a sustained elevation of co-inhibitory receptors is a hallmark of T cell exhaustion in solid tumors. Similarly, upregulation of co-inhibitory receptors has been reported in T cells in hematological cancers such as chronic lymphocytic leukemia (CLL). However, the role of CD160, a glycosylphosphatidylinositol-anchored protein, as one of these co-inhibitory receptors has been contradictory in T cell function. Therefore, we decided to elucidate how CD160 expression and/or co-expression with other co-inhibitory receptors influence T cell effector functions in patients with CLL.Methods We studied 56 patients with CLL and 25 age-matched and sex-matched healthy controls in this study. The expression of different co-inhibitory receptors was analyzed in T cells obtained from the peripheral blood or the bone marrow. Also, we quantified the properties of extracellular vesicles (EVs) in the plasma of patients with CLL versus healthy controls. Finally, we measured 29 different cytokines, chemokines or other biomarkers in the plasma specimens of patients with CLL and healthy controls.Results We found that CD160 was the most upregulated co-inhibitory receptor in patients with CLL. Its expression was associated with an exhausted T cell phenotype. CD160+CD8+ T cells were highly antigen-experienced/effector T cells, while CD160+CD4+ T cells were more heterogeneous. In particular, we identified EVs as a source of CD160 in the plasma of patients with CLL that can be taken up by T cells. Moreover, we observed a dominantly proinflammatory cytokine profile in the plasma of patients with CLL. In particular, interleukin-16 (IL-16) was highly elevated and correlated with the advanced clinical stage (Rai). Furthermore, we observed that the incubation of T cells with IL-16 results in the upregulation of CD160.Conclusions Our study provides a novel insight into the influence of CD160 expression/co-expression with other co-inhibitory receptors in T cell effector functions in patients with CLL. Besides, IL-16-mediated upregulation of CD160 expression in T cells highlights the importance of IL-16/CD160 as potential immunotherapy targets in patients with CLL. Therefore, our findings propose a significant role for CD160 in T cell exhaustion in patients with CLL

iREDS

The University of California, Riverside (UCR) proposes a new campus initiative for the cultivation of ethical climates and practices in STEM research, using a novel online communications platform combined with a project-based training designed to be compatible with that platform. We plan to deploy and evaluate a campus-wide interdisciplinary project, Institutional Re-engineering Ethical Discourse in STEM (iREDS), by examining the effects of two randomized interventions, separately and combined, and in comparison with a fourth control group receiving the standard ethics training that currently exists on campus. The overarching goal is to re-engineer ethical discourse in STEM research at the university. The project's methods use a randomized control trial (RCT) two factor design that enables both between-lab comparison among randomly assigned intervention groups and within-lab comparison over time. iREDS will introduce to selected groups of labs a free, web-based scientific communication platform, the Open Science Framework (OSF), as an everyday part of lab project workflows. The standard OSF training and its use in practice should foster more fluent communication within research groups, enhancing research methods transparency. Two other groups of labs will engage in project-based, peer-delivered ethics training, either as stand-alone or as an integrated supplement to the OSF. The peer-delivered ethics training engages lab personnel in deliberations on the ethical dimensions of the federally-funded projects in which they are engaged. Effects of the full treatment, project-based training as part of the OSF platform will be compared with OSF-only training (no project-based supplement), the stand alone project-training (no OSF presence), and a group of labs exposed to neither. We will combine quantitative comparisons of outcomes between these groups with an in-depth ethnographic study of representative labs; the ethnographic study will provide insights into the lab-level determinants of ethical climate and into the sources of heterogeneous responses to our interventions

Cross-Modal Sensory Integration of Visual-Tactile Motion Information: Instrument Design and Human Psychophysics

Information obtained from multiple sensory modalities, such as vision and touch, is integrated to yield a holistic percept. As a haptic approach usually involves cross-modal sensory experiences, it is necessary to develop an apparatus that can characterize how a biological system integrates visual-tactile sensory information as well as how a robotic device infers object information emanating from both vision and touch. In the present study, we develop a novel visual-tactile cross-modal integration stimulator that consists of an LED panel to present visual stimuli and a tactile stimulator with three degrees of freedom that can present tactile motion stimuli with arbitrary motion direction, speed, and indentation depth in the skin. The apparatus can present cross-modal stimuli in which the spatial locations of visual and tactile stimulations are perfectly aligned. We presented visual-tactile stimuli in which the visual and tactile directions were either congruent or incongruent, and human observers reported the perceived visual direction of motion. Results showed that perceived direction of visual motion can be biased by the direction of tactile motion when visual signals are weakened. The results also showed that the visual-tactile motion integration follows the rule of temporal congruency of multi-modal inputs, a fundamental property known for cross-modal integration