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51.
Sequential deposition has great potential to achieve high performance in organic solar cells due to the resulting well‐controlled vertical phase separation. In this work, double bulk heterojunction organic solar cells are fabricated by sequential‐blade cast in ambient conditions. Probed by the in situ grazing incidence X‐ray diffraction and in situ UV–vis absorption measurements, the seq‐blade system exhibits a different tendency from each of the binary films during the film formation process. Due to the extensive aggregation of FOIC, the binary PBDB‐T:FOIC film displays a strong and large phase separation, resulting in low current density (Jsc) and unsatisfactory power conversion efficiency. In the seq‐blade cast system, the bottom layer PBDB‐T:IT‐M produces many crystal nuclei for the top layer PBDB‐T:FOIC, so the PBDB‐T molecules are able to crystallize easily and quickly. Balanced crystallization kinetics between polymer and small molecule and an ideal percolation network in the film are observed. In addition, the balanced crystallization kinetics are favorable toward realizing lower recombination loss through charge transport processes.  相似文献   
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Prolonged neuroinflammation is a driving force for neurodegenerative disease, and agents against inflammatory responses are regarded as potential treatment strategies. Here we aimed to evaluate the prevention effects on gliosis by dexamethasone (DEX), an anti-inflammation drug. We used DEX to treat the nicastrin conditional knockout (cKO) mouse, a neurodegenerative mouse model. DEX (10 mg/kg) was given to 2.5-month-old nicastrin cKO mice, which have not started to display neurodegeneration and gliosis, for 2 months. Immunohistochemistry (IHC) and Western blotting techniques were used to detect changes in neuroinflammatory responses. We found that activation of glial fibrillary acidic protein (GFAP) positive or ionized calcium binding adapter molecule1 (Iba1) positive cells was not inhibited in nicastrin cKO mice treated with DEX as compared to those treated with saline. These data suggest that DEX does not prevent or ameliorate gliosis in a neurodegenerative mouse model when given prior to neuronal or synaptic loss.  相似文献   
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Cryopreservation is a valuable tool that could potentially create an alternate plant preservation strategy for species at risk such as Hill’s thistle. The present study is focused on a successful paradigm involving conservation, propagation and redistribution (CPR), emaphasizing the usefulness of cryopreservation techniques for plant conservation using Hill’s thistle (Cirsium hillii. (Canby) Fernald). A cryopreservation protocol was established using the droplet-vitrification method for 5-week-old shoot tips of in vitro grown cultures. More than 90% of shoot tips showed regrowth and nearly all regenerated plants were able to survive in the greenhouse. The survival, growth, and development of plants from cryopreserved shoot buds and their performance in field conditions were all comparable or better than the plants from non-cryopreserved buds. Reintroduced plants flowered following overwintering and the magnitude of flowering was site dependent with ca. 80% flowering observed in one site. The site dependent flowering patterns were assessed using phytohormone profiling and compared to herbivory, a common biotic stressor of these plants. Lower tryptophan concentrations led to higher flowering except in alvars, where the limestone resisted root penetration resulting in poor flowering. The presence of tryptamine in the greenhouse acclimatized or alvar field leaves suggested the preparedness of the plants for herbivory/grazing. Serotonin and melatonin concentrations were lower in flowering plants and in sites where the biotic/abiotic stress was minimal. This study provides evidence of the effectiveness of the CPR model in species recovery programs for endangered species. Physiological characterization of plants developed from cryopreserved tissues can be useful for fundamental and applied research in stress adaptation and reproductive biology of plants.

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Ji  Ruiqin  Gao  Shiqi  Bi  Qing  Wang  Yilian  Lv  Mingcan  Ge  Wenjie  Feng  Hui 《Journal of Plant Growth Regulation》2021,40(1):405-422
Journal of Plant Growth Regulation - Clubroot disease, caused by Plasmodiophora brassicae Woronin infection, leads to significant yield and economic losses in cruciferous vegetables. However, the...  相似文献   
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Zhang  Chunge  Yang  Yongchun  Hu  Tao  Zhou  Hong  Zhang  Cheng  Cao  Jian  Li  Juan  Wang  Peihan  Wong  Gary  Wang  Xiaodu  Song  Houhui  Gao  George F.  Shi  Weifeng  Bi  Yuhai 《中国病毒学》2021,36(6):1673-1677
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Gao  X.  Zhang  Y.  Mu  J. Q.  Chen  K. X.  Zhang  H. F.  Bi  K. S. 《Russian Journal of Bioorganic Chemistry》2021,47(2):420-431
Russian Journal of Bioorganic Chemistry - Guan-Xin-Shu-Tong capsule is a widely used traditional Chinese medicine for the treatment of cardiovascular diseases. However, little knowledge about the...  相似文献   
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Traumatic brain injury (TBI) was induced by a weight-drop device using 300 g–1 m weight-height impact. The study groups were: control, alpha-lipoic acid (LA) (100 mg/kg, po), TBI, and TBI + LA (100 mg/kg, po). Forty-eight hours after the injury, neurological scores were measured and brain samples were taken for histological examination or determination of thiobarbituric acid reactive substances (TBARS) and glutathione (GSH) levels, myeloperoxidase (MPO) and Na+-K+ ATPase activities, whereas cytokines (TNF-α, IL-1β) were determined in blood. Brain oedema was evaluated by wet–dry weight method and blood–brain barrier (BBB) permeability was evaluated by Evans Blue (EB) extravasation. As a result, neurological scores mildly increased in trauma groups. Moreover, TBI caused a significant decrease in brain GSH and Na+-K+ ATPase activity, which was accompanied with significant increases in TBARS level, MPO activity and plasma proinflammatory cytokines. LA treatment reversed all these biochemical indices as well as histopathological alterations. TBI also caused a significant increase in brain water content and EB extravasation which were partially reversed by LA treatment. These findings suggest that LA exerts neuroprotection by preserving BBB permeability and by reducing brain oedema probably by its anti-inflammatory and antioxidant properties in the TBI model.  相似文献   
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