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Abstract NF-kappaB (NF-κB) is a family of transcription factors with pleiotropic functions in immune responses. The alternative NF-κB pathway that leads to the activation of RelB and NF-κB2, was previously associated with the activation and function of T cells, though the exact contribution of these NF-κB subunits remains unclear. Here, using mice carrying conditional ablation of RelB in T cells, we evaluated its role in the development of conventional CD4+ T (Tconv) cells and their function in autoimmune diseases. RelB was largely dispensable for Tconv cell homeostasis, activation and proliferation, and for their polarization toward different flavors of Thelper cells in vitro. Moreover, ablation of RelB had no impact on the capacity of Tconv cells to induce autoimmune colitis. Conversely, clinical severity of experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis (MS) was significantly reduced in mice with RelB-deficient T cells. This was associated with impaired expression of granulocyte–macrophage colony-stimulating factor (GM-CSF) specifically in the central nervous system. Our data reveal a discrete role for RelB in the pathogenic function of Tconv cells during EAE, and highlight this transcription factor as a putative therapeutic target in MS.

B2O3 was used to reduce the sintering temperature of steatite (named MSB) dielectric ceramics. Electrical properties of this composition have been studied using impedance spectroscopic method to get better understanding of the electrical conduction, dielectric relaxation mechanism, and microstructure-electrical properties relationship of the materials as a function of temperature and frequency. These samples were prepared by a solid-state reaction technique and their single phase formation was confirmed by the X-ray diffraction technique. Dielectric and complex impedance spectroscopic studies were carried out in a wide frequency (102-106 Hz) and temperature (30-500°C) range. The dielectric constants decrease with increasing frequency for each sample, and then stabilize at frequencies lower than 100 kHz. The dielectric constant increases with the addition of B2O3. The nature of frequency dependence of ac conductivity of MSB follows the Jonscher power law and calculated DC conductivity follows Arrhinius behavior. The Nyquist plot (Z″ vs Z') revealed the presence only of the grain boundary effect from 350°C onwards. The occurrence of single arc in the complex modulus spectrum of MSB compositions confirms the single-phase characteristics, and also confirms the presence of non-Debye type of multiple relaxations in the material.

The Ca(Zn1/3Nb2/3)O3 (CZN) complex perovskite oxide has been studied for its attractive dielectric properties (εr=34, Qxf=15 890GHz, τf=-48 ppm.°C-1) for applications such as multilayer ceramics capacitors or hyperfrequency resonators. Nevertheless, high temperatures (>1250°C) are required to obtain well dense CZN ceramic, prohibiting any silver co-sintering (Tf (Ag) = 961°C). For that reason, the sintering temperature lowering of CZN by glass phase’s additions has been investigated. This material is finally sinterable at low temperature with combined glass phase -lithium salt additions, and exhibits, at 1MHz, very low dielectric losses, a relatively high dielectric constant with a good stability versus temperature. The 2%weight of ZnO-SiO2-B2O3 glass phase and 1%wt of LiF added CZN sample sintered at 920°C exhibits a relative density higher than 95% and attractive dielectric properties: a dielectric constant εr of 22, low dielectrics losses (tan (δ)< 10-3), a temperature coefficient of the permittivity τε

Kinetics of the hydroprocessing of anisole, a compound representative of lignin-derived bio-oils, catalyzed by a commercial sulfided CoMo/Al2O3, was determined at 8–20 bar pressure and 573–673 K with a once-through flow reactor. The catalyst was sulfided in an atmosphere of H2 + H2S prior to the measurement of its performance. Selectivity-conversion data were used as a basis for determining an approximate, partially quantified reaction network showing that hydrodeoxygenation (HDO), hydrogenolysis, and alkylation reactions take place simultaneously. The data indicate that these reactions can be stopped at the point where HDO is virtually completed and hydrogenation reactions (and thus H2 consumption) are minimized. Phenol was the major product of the reactions, with direct deoxygenation of anisole to give benzene being kinetically almost insignificant under our conditions. We infer that the scission of the Cmethyl–O bond is more facile than the scission of the Caromatic–O bond, so that the HDO of anisole likely proceeds substantially through the reactive intermediate phenol to give transalkylation products such as 2-methylphenol. The data determine rates of formation of the major primary products. The data show that if oxygen removal is the main processing goal, higher temperatures and lower pressures are favored.

This study aimed to investigate the protective effects of curcuma against hexavalent chromium-induced alterations in reproduction indices of male Wistar rats. Twenty adult male Wistar rats were divided into four groups. The first group (0-0): control. The second group (0-Cur) received a diet with 2% curcuma powder. The third group (Cr-0) received 15 mg/kg B.W. of potassium dichromate (K2Cr2O7) per os, while the last group (Cr-Cur) received a diet containing 2% curcuma powder and 15 mg/kg B.W. of K2Cr2O7 per os. After 30 days of treatment, testicular weight, sperm concentration, sperm kinematic parameters, and testicular glutathione (GSH) level were evaluated. Our results suggest that hexavalent chromium causes a decrease in sperm concentration, total progression, total motility, fast motility, medium motility, slow motility, static sperm, linearity (LIN), straightness (STR), amplitude of lateral head displacement (ALH), beat cross frequency (BCF), sperm velocity, and testicular GSH level, accompanied with an increase in testicular weight and wobble (WOB) level when compared to control group. However, supplementation with curcuma of chromium-intoxicated rats has reduced the toxic effect of K2Cr2O7 by bringing back the reproductive parameters and GSH levels to normal values. From this finding, it can be implicated that diet supplemented with curcuma powder may show protective effects against chromium toxicities. [ABSTRACT FROM AUTHOR]

Background and Objectives: The emergence of COVID-19 has brought about a sudden shift to e-learning and virtual platforms. Teachers play a key role in developing e-learning content. Hence, they must be familiar with the theories related to the cognitive constructs and e-learning principles to both facilitate the learning process and enhance the rate of learning and retention among the students. The cognitive load might increase unless the e-learning and experiential content is not developed according to the cognitive load theory, particularly for teaching physics as a field that requires multimodal presentation of the content. This might hinder the students' learning and retention. In other words, if the principles of cognitive load theory are not observed in the design of electronic and multimedia content of course materials, the learning process will be disturbed and damaged due to the production of additional load beyond the memory capacity of the learners. The current study aimed to develop e-learning content for a concept in physics (e.g. pressure) based on the cognitive load theory. It further attempted to explore its possible impact on the learners' levels of learning (knowledge, understanding, application) and the degree of their retention. Materials and Methods: The study adopted a quasi-experimental pre-test post-test design with an experimental and a control group. The statistical population included all female ninth graders in district 17, Tehran, the capital of Iran. The sample consisted of 120 learners via multistage stratified random sampling procedures. The participants were assigned to experimental and control groups. To gather the required data, a researcher-made test was used and its reliability was calculated via Cronbach's alpha as 0.85. The students took part in a three-week virtual empirical sciences course comprising six sixty-minute sessions. Before offering the course, the educational objectives of chapter 8 of the empirical sciences textbook in the ninth grade related to the subject "pressure" were determined using the teacher's manual and eliciting the experienced sciences and physics teachers' expert comments. Then, their level of cognitive processing was identified based on Bloom's taxonomy. The objectives were categorized into three groups of knowledge, understanding, and application. To analyze the data, analysis of covariance and an independent samples t-test were used via SPSS (20.00). Findings: The results of the analysis of covariance for learning levels (knowledge, understanding, and application) demonstrated that developing e-learning materials based on the cognitive load theory enhanced the learners' levels of learning in the experimental group compared to those in the control group (P < 0.05). Moreover, the results of an independent samples t-test for the delayed post-test revealed a significant difference between the participants in experimental and control groups in terms of their degree of retention (P < 0.01). Conclusions: The findings implied that considering the principles of the cognitive load theory in developing e-learning materials for physics would positively influence the learners' levels of learning and their degree of retention. Therefore, it is recommended to designers of e-learning content to consider the principles of cognitive load theory in the design and production of their content. [ABSTRACT FROM AUTHOR]