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Pertussis toxin (PTX) is a required co-adjuvant for experimental autoimmune encephalomyelitis (EAE) induced by immunization with myelin antigen. However, PTX’s effects on EAE induced by the transfer of myelin-specific T helper cells is not known. Therefore, we investigated how PTX affects the Th17 transfer EAE model (Th17-EAE). We found that PTX significantly reduced Th17-EAE by inhibiting chemokine-receptor-dependent trafficking of Th17 cells. Strikingly, PTX also promoted the accumulation of B cells in the CNS, suggesting that PTX alters the disease toward a B-cell-dependent pathology. To determine the role of B cells, we compared the effects of PTX on Th17-EAE in wild-type (WT) and B-cell-deficient (µMT) mice. Without PTX treatment, disease severity was equivalent between WT and µMT mice. In contrast, with PTX treatment, the µMT mice had significantly less disease and a reduction in pathogenic Th17 cells in the CNS compared to the WT mice. In conclusion, this study shows that PTX inhibits the migration of pathogenic Th17 cells, while promoting the accumulation of pathogenic B cells in the CNS during Th17-EAE. These data provide useful methodological information for adoptive-transfer Th17-EAE and, furthermore, describe another important experimental system to study the pathogenic mechanisms of B cells in multiple sclerosis.  相似文献   
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Multibody System Dynamics - In this study, the three-compartment controller fatigue model is integrated with an inverse dynamics optimization routine to predict the optimal posture, joint fatigue,...  相似文献   
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The insecticidal activity of nanosilica particles (NSPs) [20 ± 4 nm] was determined using the saw-toothed grain beetle, Oryzaephilus surinamensis (L) adults as the experimental insect. When the unsexed adults were exposed to different doses of nanosilica (0.2, 0.4, 0.6, 0.8 and 1.0 mg/Petri dish) for different periods (1, 2 and 3 days), it was found that NSPs had more insecticidal activity against O. surinamensis. Moreover, it was found that as the exposure time and dose increased, the mortality percentages of the adults increased. When the adult fed on irradiated dates which treated with different doses of nanosilica (0.5, 1,2 and 4 mg/1date) the mortality was higher than in nanosilica alone. The LD50 of the bioassay tests showed that the calculated LD50 values of each treatment were 0.468, 1.201 and 0.572 mg/1date. The adult of O. surinamensis (untreated, treated with LD50 of nanosilica and fed on unirradiated or irradiated dates) examined by a scanning electron microscope. The examination showed the same malformations in all treatments which caused abrasion and damage on the outer surface. Nanosilica can be effectively replacing chemical insecticides to protect stored products.  相似文献   
5.
Cassava root spoils rapidly after harvest but can be well preserved by storing under freezing. This study investigated the functional, chemical and physicochemical properties of flour produced from frozen cassava roots. Freezing period did not significantly (p < 0.05) alter the moisture, ash, fat and fibre, but had slight effect on the carbohydrate and protein contents of the flour. Lightness, yellowness index and bulk densities of the flour samples reduced with freezing period. While freezing did not significantly (p < 0.05) change the ability of the flour samples to absorb oil, a slight but significant increase in the water absorption capacity was observed. Potassium (1.29–3.46 mg/kg), sodium (1.24–1.28 mg/kg), and calcium (0.94–1.34 mg/kg) were the major minerals in the cassava flour samples. The cyanide content (10.80–22.95 mg/kg) reduced as freezing days increased but peak, setback, breakdown and final viscosities did not follow a particular pattern. The information from this study is important to further determine the industrial potentials of flour from stored cassava roots.  相似文献   
6.
This work studies the supply allocation problem, using a Stackelberg game, for an established timberlands supply chain with an additional decision of new biorefinery investments. In a timberlands system, harvester and manufacturer decision makers have separate objectives to maximize their respective profits. This interaction is represented with a turn based Stackelberg game. The harvesters decide first on the quantity harvested, and the manufacturers decide on how much to utilize. This game is modeled with a bilevel mathematical program. The novel feature of this paper's bilevel formulation is the inclusion of parametric uncertainty in a two stage model. The first stage problem involves logistical decisions around biorefinery investments, such as location and capacity, while the second stage problem involves a bilevel timberlands model with parameter uncertainty. Studying this problem formulation revealed interesting insights for solving multiperiod problems with bilevel stages as well as the decision maker's behavior for the timberlands model.  相似文献   
7.
In this study, we used Callosobruchus maculatus as a model insect to assess the idea of whether or not environmental conditions experienced by parents subsequently moderate offspring fitness and competency. We observed that parents’ experiences (sex ratio of parents, restricted access to mates, and honey access) influenced their offspring’s features and did not significantly affect traits such as offspring sex ratio, larval duration, and longevity. However, not only offspring (F1) but also grand-offspring (F2) copulation behaviors, egg number, and hatching percentage were influenced by parents’ experiences. Hence, the offspring of parents living in unfavorable conditions had higher copulation success, higher male mating propensity, and a lower mating latency time in adulthood than the progeny of parents kept under natural or favorable conditions. Interestingly, the offspring of parents with favorable living conditions showed the least tendency to copulate immediately. Even grandparents’ experience could affect descendant behaviors and shorten copulation duration. Adjustments of the parents to their environment were inherited by offspring and grand-offspring to cope better with challenging circumstances and might make the organism more competent. Therefore, the parents’ living conditions have a remarkable impact on how their progeny behave in different situations.  相似文献   
8.
Bioethanol is an eco-friendly biofuel due to its merit that makes it a top-tier fuel. The present study emphasized on bioethanol production from hydrogen-rich syngas through fermentation using Sacharomyces cerevisiea. Syngas fermentation was performed in a tar free fermenter using a syngas mixture of 13.05% H2, 22.92% CO, 7.9% CO2, and 1.13% CH4, by volume. In the fermentation process, effects of various parameters including syngas impurity, temperature, pH, colony forming unit, total organic carbon and syngas composition were investigated. The yield of bioethanol was identified by Gas chromatography-Mass spectrometry analysis and further, it was confirmed by Nuclear magnetic resonance (1H) analysis. From GC-MS results, it is revealed that the concentration of bioethanol using Saccharomyces cerevisiae was 30.56 mmol from 1 L of syngas. Thus, hydrogen-rich syngas is suited for bioethanol production through syngas fermentation using Saccharomyces cerevisiae. This research may contribute to affordable and environment-friendly bioethanol-based energy to decrease the dependency on fossil fuels.  相似文献   
9.
Barberry is a nutritional and therapeutic crop mostly dried and consumed in bulk. However, the lack of proper packaging leads to the decline of many of its valuable properties. The aim of this study was to investigate the effect of different packaging films on barberries properties during storage. 150 g of freshly dried barberries were kept for 6 months at 25 °C within different packaging materials: (i) low-density polyethylene (LDPE); two laminated layers film including LDPE and polyethylene terephthalate (PET) with a total thickness of (ii) 45 μm (LDPE/PET-45) and (iii) 60 μm (LDPE/PET-60); (iv) oriented polypropylene (OPP); (v) three laminated layers film of OPP (3OPP); (vi) three laminated layers film including LDPE, metalized PET and PET (LDPE/mPET/PET); and (vii) four laminated layers film including LDPE, PET, aluminum foil and PET (LDPE/PET/Al/PET). After six months, the least change in moisture content, the lowest loss of DPPH scavenging capacity (97.9%), the minimum overall color difference, and the least increase in acidity (39.3%) were related to barberries packaged in the LDPE/PET-45 film. This is while the lowest loss of ascorbic acid (99.8%) and anthocyanin (62.8%) contents and the minimum microbial deterioration were related to the LDPE/PET-60 film. On the other hand, the LDPE/PET/Al/PET film entailed the lowest barberry weight loss (0.67%) and the minimum increase in firmness (40.7%), while the 3OPP film providing the best preservation of phenolic compounds. In conclusion, it seems two laminated layers films composed of LDPE and PET are appropriate for the preservation of dried barberries during storage.  相似文献   
10.
No longer is it appropriate to evaluate processes for economic feasibility alone; social benefits and environmental impacts must also be considered. This work develops a multi criteria systematic framework for optimum process design with sustainability considerations and addresses a major challenge in process design as engineers will now be able to design for multiple criteria, specifically sustainability concerns. A novel multi objective optimization algorithm capable of handling a multitude of objectives in mixed integer nonlinear search space and a novel decision making methodology are integrated with a sequential modular process simulator to optimize processes with a multitude of objectives rigorously and efficiently. The application of this research extends well beyond sustainability considerations to the very vast area of optimum design with multi criteria. The application of the proposed framework is demonstrated through a case study for process retrofit of Dimethyl Ether production plant.  相似文献   
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