Enhancing Optical,Electronic, Crystalline,and Morphological Properties of Cesium Lead Halide by Mn Substitution for High‐Stability All‐Inorganic Perovskite Solar Cells with Carbon Electrodes

In this work all‐inorganic perovskite CsPbIBr₂ are doped with Mn to compensate their shortcomings in band structure for the application of perovskite solar cells (PSCs). The novel Mn‐doped all‐inorganic perovskites, CsPb_1?xMn_xI_1+2xBr_2?2x, are prepared in ambient atmosphere. As the concentration of Mn²⁺ ions increases, the bandgaps of CsPb_1?xMn_xI_1+2xBr_2?2x decrease from 1.89 to 1.75 eV. Additionally, when the concentration of Mn dopants is appropriate, this novel Mn‐doped all‐inorganic perovskite film shows better crystallinity and morphology than its undoped counterpart. These advantages alleviate the energy loss in hole transfer and facilitate the charge‐transfer in perovskites, therefore, PSCs based on these novel CsPb_1?xMn_xI_1+2xBr_2?2x perovskite films display better photovoltaic performance than the undoped CsPbIBr₂ perovskite films. The reference CsPbIBr₂ cell reaches a power conversion efficiency (PCE) of 6.14%, comparable with the previous reports. The CsPb_1?xMn_xI_1+2xBr_2?2x cells reach the highest PCE of 7.36% (when x = 0.005), an increase of 19.9% in PCE. Furthermore, the encapsulated CsPb_0.995Mn_0.005I_1.01Br_1.99 cells exhibit good stability in ambient atmosphere. The storage stability measurements on the encapsulated PSCs reveal that PCE is dropped by only 8% of the initial value after >300 h in ambient. Such improved efficiency and stability are achieved using low‐cost carbon electrodes (without expensive hole transport materials and Au electrodes).     

Aragonite shells are more ancient than calcite ones in bivalves: new evidence based on omics

Two calcium carbonate crystal polymorphs, aragonite and calcite, are the main inorganic components of mollusk shells. Some fossil evidences suggest that aragonite shell is more ancient than calcite shell for the Bivalvia. But, the molecular biology evidence for the above deduction is absent. In this study, we searched for homologs of bivalve aragonite-related and calcite-related shell proteins in the oyster genome, and found that no homologs of calcite-related shell protein but some homologs of aragonite-related shell proteins in the oyster genome. We explained the results as the new evidence to support that aragonite shells are more ancient than calcite shells in bivalves combined the published biogeological and seawater chemistry data.     

Establishment of Mammary Gland Model In Vitro: Culture and Evaluation of a Yak Mammary Epithelial Cell Line

This study aimed to establish yak mammary epithelial cells (YMECs) for an in vitro model of yak mammary gland biology. The primary culture of YMECs was obtained from mammary gland tissues of lactating yak and then characterized using immunocytochemistry, RT-PCR, and western blot analysis. Whether foreign genes could be transfected into the YMECs were examined by transfecting the EGFP gene into the cells. Finally, the effect of Staphylococcus aureus infection on YMECs was determined. The established YMECs retained the mammary epithelial cell characteristics. A spontaneously immortalized yak mammary epithelial cell line was established and could be continuously subcultured for more than 60 passages without senescence. The EGFP gene was successfully transferred into the YMECs, and the transfected cells could be maintained for a long duration in the culture by continuous subculturing. The cells expressed more antimicrobial peptides upon S.aureus invasion. Therefore, the established cell line could be considered a model system to understand yak mammary gland biology.     

Spatial distribution characteristics of stomata at the areole level in Michelia cavaleriei var. platypetala (Magnoliaceae)

Background and AimsIn hierarchically reticulate venation patterns, smaller orders of veins form areoles in which stomata are located. This study aimed to quantify the spatial relationship among stomata at the areole level.MethodsFor each of 12 leaves of M. cavaleriei var. platypetala, we assumed that stomatal characteristics were symmetrical on either side of the midrib, and divided the leaf surface on one side of the midrib into six layers equidistantly spaced along the apical–basal axis. We then further divided each layer into three positions equidistantly spaced from midrib to leaf margin, resulting in a total of 18 sampling locations. In addition, for 60 leaves, we sampled three positions from midrib to margin within only the widest layer of the leaf. Stomatal density and mean nearest neighbour distance (MNND) were calculated for each section. A replicated spatial point pattern approach quantified stomatal spatial relationships at different distances (0–300 μm).Key ResultsA tendency towards regular arrangement (inhibition as opposed to attraction or clustering) was observed between stomatal centres at distances <100 μm. Leaf layer (leaf length dimension) had no significant effect on local stomatal density, MNND or the spatial distribution characteristics of stomatal centres. In addition, we did not find greater inhibition at the centre of areoles, and in positions farther from the midrib.ConclusionsSpatial inhibition might be caused by the one-cell-spacing rule, resulting in more regular arrangement of stomata, and it was found to exist at distances up to ~100 μm. This work implies that leaf hydraulic architecture, consisting of both vascular and mesophyll properties, is sufficient to prevent important spatial variability in water supply at the areole level.     

Effects of NMDAR Antagonist on the Regulation of P-MARCKS Protein to Aβ<Subscript>1−42</Subscript> Oligomers Induced Neurotoxicity

Alzheimer’s disease (AD) is a well-known neurodegenerative disease. Deposition of β-amyloid protein (Aβ) oligomers plays a crucial role in the disease progression. Previous studies showed that toxicity induced by Aβ oligomers in cultured neurons and adult rat brain was partially mediated by activation of glutamatergic N-methyl-d-aspartate receptors (NMDAR). Additionally, memantine, a noncompetitive NMDAR antagonist, can significantly improve cognitive functions in some AD patients. However, little is currently known about the potential role of NMDAR antagonist on the regulation of P-MARCKS protein to Aβ_1?42 oligomers induced neurotoxicity. The protective effect and mechanism of NMDAR antagonist on primary neurons exposed to Aβ_1?42 oligomers were investigated in the study. We have defined that the Aβ_1?42 treatment decreased cell viability and increased apoptosis. Moreover, Aβ_1?42 oligomers exposure increased P-MARCKS and PIP2 expressions, while decreased SYP expression. However, NMDAR antagonist pretreatment ameliorates Aβ_1?42 oligomers induced neuronal apoptosis and partially reverses the expression of P-MARCKS, PIP2 and SYP. In conclusion, NMDAR antagonist may ameliorate neurotoxicity induced by Aβ_1?42 oligomers through reducing neuronal apoptosis and protecting synaptic plasticity in rat primary neurons. The mechanism involved may be mediated by the variation of protein P-MARCKS.     

A two‐component histidine kinase Shk1 controls stress response,sclerotial formation and fungicide resistance in Sclerotinia sclerotiorum

Fungal histidine kinases (HKs) are involved in osmotic and oxidative stress responses, hyphal development, fungicide sensitivity and virulence. Members of HK class III are known to signal through the high‐osmolarity glycerol mitogen‐activated protein kinase (HOG MAPK). In this study, we characterized the Shk1 gene (SS1G_12694.3), which encodes a putative class III HK, from the plant pathogen Sclerotinia sclerotiorum. Disruption of Shk1 resulted in resistance to phenylpyrrole and dicarboximide fungicides and increased sensitivity to hyperosmotic stress and H₂O₂‐induced oxidative stress. The Shk1 mutant showed a significant reduction in vegetative hyphal growth and was unable to produce sclerotia. Quantitative real‐time polymerase chain reaction (qRT‐PCR and glycerol determination assays showed that the expression of SsHOG1 (the last kinase of the Hog pathway) and glycerol accumulation were regulated by the Shk1 gene, but PAK (p21‐activated kinase) was not. In addition, the Shk1 mutant showed no change in virulence. All the defects were restored by genetic complementation of the Shk1 deletion mutant with the wild‐type Shk1 gene. These findings indicate that Shk1 is involved in vegetative differentiation, sclerotial formation, glycerol accumulation and adaption to hyperosmotic and oxidative stresses, and to fungicides, in S. sclerotiorum. Taken together, our results demonstrate, for the first time, the role of two‐component HKs in Sclerotinia.