Temperature-dependent photoluminescence of lead-free cesium tin halide perovskite microplates

Tin halide perovskites recently have attracted extensive research attention due to their similar electronic and band structures but non-toxicity compared with their lead analogues. In this work, we prepare high-quality CsSnX_(3)(X=Br,I) microplates with lateral sizes of around 1–4 μm by chemical vapor deposition and investigate their low-temperature photoluminescence(PL) properties. A remarkable splitting of PL peaks of the CsSnBr_(3)microplate is observed at low temperatures. Besides the possible structural phase transition at below 70 K, the multi-peak fittings using Gauss functions and the power-dependent saturation phenomenon suggest that the PL could also be influenced by the conversion from the emission of bound excitons into free excitons. With the increase of temperature, the peak position shows a blueshift tendency for CsSnI_(3), which is governed by thermal expansion. However, the peak position of the CsSnBr3microplate exhibits a transition from redshift to blueshift at ~160 K. The full width at half maximum of CsSnX_(3)broadens with increasing temperature, and the fitting results imply that longitudinal optical phonons dominate the electron–phonon coupling and the coupling strength is much more robust in CsSnBr3than in CsSnI_(3). The PL intensity of CsSnX_(3)microplates is suppressed due to the enhanced non-radiative relaxation and exciton dissociation competing with radiative recombination. According to the Arrhenius law, the exciton binding energy of CsSnBr_(3)is ~38.4 meV, slightly smaller than that of CsSnI_(3).

Effects of Maize Silage Harvest Stage on Growth Performance and Economic Benefits of Beef Cattle

[Objectives]This study aimed to investigate the effects of whole-crop maize silage harvested at different stages on growth and economic benefits of beef cattle.[Methods]A total of 30 Simmental crossbred cattle weighing about 378 kg were randomly divided into three groups,respectively fed for 70 days with whole-crop maize silage harvested at milk stage(GroupⅠ),dough stage(GroupⅡ)and physiological maturity stage(GroupⅢ).Moreover,the cattle in all groups were given the same concentrate diet.[Results]There were significant differences in dry matter,crude protein and neutral detergent fiber between whole-crop maize silages harvested at different stages(P<0.05).The dry matter in GroupⅡandⅢwas significantly higher than that in GroupⅠ(P<0.05).The crude protein content peaked in GroupⅡ,up to 6.37%,which was significantly higher than that in GroupⅠ(by 12.74%,P<0.05)and GroupⅢ(by 9.26%,P<0.05).Starch content significantly increased with the postponing of maize harvest(P<0.05).The content of neutral detergent fiber in Group I was significantly higher than that in GroupⅡ(P<0.05)and GroupⅢ(P<0.05).The average daily weight gain in GroupⅡwas 8.53%higher than that in GroupⅠ(P<0.05)and 3.70%higher than that in GroupⅢ(P>0.05).The dry matter intake in GroupⅡwas significantly higher than that in GroupⅠ(P<0.05)and GroupⅢ(P<0.05).There was no significant difference in feed/gain ratio between the groups(P>0.05).The economic benefit in GroupⅡwas the highest,up to 9.99 yuan/day per capita.,followed by that in GroupⅢ,9.79 yuan/day per capita,and that in GroupⅠwas the lowest,only 8.03 yuan/day per capita.[Conclusions]The whole-crop maize silage harvested at dough stage has the best quality and produces the highest economic returns for beef cattle.

Effects of Whole-plant Corn Silage and Whole-plant Wheat Silage on Growth Performance and Economic Benefits of Beef Cattle

[Objectives]This study was conducted to study the effects of whole-plant corn silage and whole-plant wheat silage on growth performance and economic benefits of beef cattle.[Methods]Thirty Simmental crossbred cattle were selected and randomly divided based on their weight into two groups,15 cows in each group,with an average weight of 398 kg.Each group was fed the same concentrated feed,and the whole-plant corn silage and wheat silage were fed as roughage feed,respectively.The experimental period was 90 d.[Results](1)There was no significant difference in the initial weight of beef cattle between test group 1 and test group 2(P>0.05).Compared with group 2,group 1 had a higher final weight,average daily gain,and dry matter intake of beef cattle,without significant differences(P>0.05).Group 1 was 0.58%,1.99%,and 1.43%higher than group 2,respectively.The feed-to-gain ratio of test group 1 decreased by 0.54%compared with test group 2(P>0.05),with no significant difference therebetween.(2)The economic benefit of group 1 was 11.45 yuan/(day·capita),while the economic benefit of group 2 was 2.41 yuan/(day·capita),and group 1 was 9.04 yuan/(day·capita)higher than group 2.[Conclusions]Whole-plant corn silage for feeding beef cattle has the advantages of good weight gain and low breeding cost,and can be popularized in beef cattle fattening.

Analysis on nursing competence and training needs of dementia caregivers in long-term care institutions

Objective:It is aimed to investigate the nursing competence and corresponding influence factors of dementia caregivers in long-term care institutions of Tianjin and identify the training needs of caregivers.Methods:In the cross-section survey of this study,246 dementia caregivers were selected from 6 long-term care institutions in Tianjin as objects of study through convenient sampling.Results:The scores for nursing competence of dementia caregivers were 140.28±7.73,at a moderate level.Study findings that nursing competence of dementia caregivers were positively associated with the work experience(β=0.115,P=0.005),educational level(β=0.333,P<0.01),pervdceived health status(β=0.108,P=0.003)and training times within 1 year(β=0.371,P<0.01).Through the analysis,it is found that the training needs of dementia caregivers are inconsistent with the current situation in terms of content,methods and teachers.There are some problems in the training,such as unreasonable time,single mode and not deepening the understanding of the elderly with dementia.Conclusion:Long term care institutions shall arrange training no less than 12 times a year and evaluate training needs regularly to improve training effect.Providing online and offline training and adding more specialized contents like case analysis,employing experts in the field of dementia to teach courses.

甲壳素纳米纤维/碳纳米管复合凝胶膜的制备与性能

将甲壳素纳米纤维与碳纳米管在水性条件下混合,建立甲壳素纳米纤维均匀分散的碳纳米管混合体系;利用真空抽滤制备甲壳素纳米纤维/碳纳米管复合膜,通过20%氢氧化钠低温处理制备具有连续三维纳米网络结构的复合凝胶膜,并对比凝胶化前后样品微观结构、导电性能及电化学性能等。结果表明,凝胶化处理有助于在凝胶膜内部构建三维纳米导电网络,当甲壳素纳米纤维与碳纳米管的质量比为1∶1时,凝胶膜的导电率和质量比电容较复合膜提高了2倍;2000次循环测试后,凝胶膜的比电容量仍能保持为起始比电容量的92.5%,循环稳定性较好。

鸟鸣多样性感知与声景感知恢复性:鸟鸣音频和科普的干预

自然声景具有感知恢复性,让人从疲劳中恢复,鸟鸣是声景中的重要组成,研究鸟鸣对声景感知恢复性的影响,可以为公众从自然中获得更高水平的感知恢复性效益提供参考依据。2021年7–8月,我们在北京西山国家森林公园使用播放鸟鸣的扬声器增加环境中的鸟鸣多样性,设置标识牌以提供当地常见鸟类及鸟鸣的科普信息,并对744名游客进行问卷调查,了解游客获得的声景感知恢复性和对鸟鸣多样性的感知水平。研究发现处在鸟鸣多样性更丰富环境的游客获得了更高水平的声景感知恢复性效益,获得鸟鸣科普信息的游客感知到了更高水平的鸟鸣多样性,游客感知的鸟鸣多样性与实际鸟鸣多样性不相关。结果表明声景恢复性与环境中鸟鸣多样性呈正相关,更丰富的鸟鸣多样性能够改善游客在自然环境中的游览体验并受益,标识牌能够促进游客关注环境,提高感知到的鸟鸣数量。

设计并构建Ⅰ型SnSe_(2)/ZnS异质结构提升其光电化学探测及水分解性能

二维范德瓦尔斯异质结构广泛应用于光电化学(PEC)型光电探测器、水分解和太阳能电池等光电器件中.其中,Ⅰ型异质结构对于设计新型光电器件至关重要,然而其能带排列对光电响应的影响尚不清楚.本文利用两步物理气相沉积法构建了Ⅰ型SnSe_(2)/ZnS异质结构,并通过紫外光电子能谱和X射线光电子能谱进行了验证.基于Ⅰ型SnSe_(2)/ZnS异质结构的光电化学探测器在紫外可见范围内具有良好的光响应、高稳定性和高灵敏度.SnSe_(2)/ZnS的光响应可达172.60μA W^(-1),分别是单一ZnS和SnSe_(2)样品的7.4和2.0倍.并且,SnSe_(2)/ZnS异质结构具有较高的光电催化分解水活性,在2 h内总产氢量可达81.25μmol cm-2.SnSe_(2)/ZnS异质结优异的光电探测和水分解性能主要源于其更高的光利用率和高效电荷传输的协同作用.本工作为通过构建Ⅰ型异质结构来提高光电响应并设计高性能光电探测器和水分解等光电器件提供了一种新方法.

Surveillance of emerging infectious diseases for biosecurity

Emerging infectious diseases, such as COVID-19, continue to pose significant threats to human beings and their surroundings. In addition, biological warfare, bioterrorism, biological accidents, and harmful consequences arising from dual-use biotechnology also pose a challenge for global biosecurity. Improving the early surveillance capabilities is necessary for building a common biosecurity shield for the global community of health for all. Furthermore, surveillance could provide early warning and situational awareness of biosecurity risks. However, current surveillance systems face enormous challenges, including technical shortages, fragmented management, and limited international cooperation. Detecting emerging biological risks caused by unknown or novel pathogens is of particular concern. Surveillance systems must be enhanced to effectively mitigate biosecurity risks. Thus, a global strategy of meaningful cooperation based on efficient integration of surveillance at all levels, including interdisciplinary integration of techniques and interdepartmental integration for effective management, is urgently needed. In this paper, we review the biosecurity risks by analyzing potential factors at all levels globally. In addition to describing biosecurity risks and their impact on global security, we also focus on analyzing the challenges to traditional surveillance and propose suggestions on how to integrate current technologies and resources to conduct effective global surveillance.

Hybrid coordinated strategy of downlink coordinated multi-point transmission

Coordinated multi-point(CoMP) transmission is put forward in the long term evolution-advanced(LTE-A) system to improve both average and cell-edge throughput. CoMP-joint processing(JP) scheme can get a larger cell-edge throughput and a lower bit error rate(BER) than the CoMP-coordinated beamforming(CB) scheme, but it also has higher complexity due to data sharing. A hybrid coordinated strategy with parameter α, which indicates the proportion of users employing the CoMP-JP scheme,is proposed to apply the CoMP-JP scheme to improve the poorer communication quality of cell edge and employ the CoMP-CB scheme for other users to enhance average throughput and spectral efficiency. This paradigm selects users defined by the certain threshold of signal to interference plus noise power ratio(SINR)corresponding to the parameter α to the CoMP-JP scheme. This paper compares the BER performance between the block diagonalization(BD) based precoding and the linear precoders by maximizing signal to leakage and noise ratio(SLNR), and also indicates that the SLNR based precoding algorithm gets lower BER than the BD based precoding algorithm with certain signal-to-noise ratios(SNRs). Finally, this paper discusses that the system performance is partially affected by the percentage of CoMP-JP users and concludes that 50% of users sorted to communicate under the CoMP-JP scheme will reach the best system performance.

The transcription factor KLF14 regulates macrophage glycolysis and immune function by inhibiting HK2 in sepsis

Sepsis is a heterogeneous syndrome induced by a dysregulated host response to infection.Glycolysis plays a role in maintaining the immune function of macrophages,which is crucial for severely septic patients.However,how the pathways that link glycolysis and macrophages are regulated is still largely unknown.Here,we provide evidence to support the function of KLF14,a novel Krüppel-like transcription factor,in the regulation of glycolysis and the immune function of macrophages during sepsis.KLF14 deletion led to significantly increased mortality in lethal models of murine endotoxemia and sepsis.Mechanistically,KLF14 decreased glycolysis and the secretion of inflammatory cytokines by macrophages by inhibiting the transcription of HK2.In addition,we confirmed that the expression of KLF14 was upregulated in septic patients.Furthermore,pharmacological activation of KLF14 conferred protection against sepsis in mice.These findings uncover a key role of KLF14 in modulating the inflammatory signaling pathway and shed light on the development of KLF14-targeted therapeutics for sepsis.

构建Ⅰ型SnS_(2)/Bi_(2)Se_(3)和Ⅱ型SnS_(2)/Bi_(2)Te_(3)范德瓦尔斯异质结构提升其光电性能

基于新型先进材料的异质结构为提高光电器件的光电性能奠定了基石.能带排列是理解异质结构中载流子输运机理和界面动力学的关键.本文利用物理气相沉积法和化学气相沉积法制备了SnS_(2)/Bi_(2)X_(3)(X=Se,Te)范德华异质结构.通过高分辨率X射线光电子能谱测量的能带排列证实了Ⅰ型SnS_(2)/Bi_(2)Te_(3)和Ⅱ型SnS_(2)/Bi_(2)Te_(3)异质结构的成功制备.基于SnS_(2)/Bi_(2)X_(3)异质结构的光电化学型光电探测器的光电响应得到了极大的提高.Ⅰ型SnS_(2)/Bi_(2)Te_(3)和Ⅱ型SnS_(2)/Bi_(2)Te_(3)异质结构的光电流密度均比SnS_(2)、Bi_(2)Te_(3)和Bi_(2)Te_(3)的光电流密度高一个数量级以上.SnS_(2)/Bi_(2)X_(3)异质结构光电性能的显著提高主要是由于:(i)异质结构中光激发电子和空穴的有效分离;(ii)SnS_(2)/Bi_(2)X_(3)异质结构与电解质界面具有更高的电荷转移效率和载流子密度;(iii)异质结构的构建拓宽了光的吸收范围.此外,直立的SnS_(2)还可以有效地捕获光子以提高其光电性能.Ⅰ型SnS_(2)/Bi_(2)Te_(3)异质结构的光电性能优于Ⅱ型SnS_(2)/Bi_(2)Te_(3)异质结构,这主要源于异质结构/电解质界面上更高效的电荷传输能力.实验研究结果表明,Ⅰ型和Ⅱ型异质结构的构建为开发高性能光电探测器及其他光电器件提供了新思路.

Inclusion Complex of Podophyllotoxin with y-Cyclodextrin Preparation, Characterization, Anticancer Activity, Water-Solubility and Toxicity

An inclusion complex of podophyllotoxin （PPT） with 7-cyclodextrin （7-CD） was prepared. The behavior, char- acterization, and water solubility of the inclusion complex were carefully investigated via fluorescence spectroscopy, thermogravimetry, differential scanning calorimetry, X-ray diffraction analysis, and 1H and 2D nuclear magnetic resonance spectroscopy. Furthermore, antitumor activity to human cancer lines and toxicity in mice were studied. Results showed that the inclusion complex formed in a 1 ： 1 ratio with a considerable apparent stability constant Ks （4245.5 Lomol-l）. Water solubility was considerably improved. In addition, the anticancer activity of the inclusion complex was better than that of cis-platinum （DDP, positive control）. Most importantly, the toxicity of podophyl- lotoxin inclusion complex reduced and became more safety to mice which will be great valuable to research its ap- plications as a kind of antitumor drug to human in the further.

Facile route to achieve MoSe2-Ni3Se2 on nickel foam as efficient dual functional electrocatalysts for overall water splitting

Since the catalytic activity of present nickel-based synthetic selenide is still to be improved, MoSe2-Ni3Se2 was synthesized on nickel foam (NF) (MoSe2-Ni3Se2/NF) by introducing a molybdenum source. After the molybdenum source was introduced, the surface of the catalyst changed from a single-phase structure to a multiphase structure. The catalyst surface with enriched active sites and the synergistic effect of MoSe2 and Ni3Se2 together enhance the hydrogen evolution reactions (HER), the oxygen evolution reactions (OER), and electrocatalytic total water splitting activity of the catalyst. The overpotential of the MoSe2-Ni3Se2/NF electrocatalyst is only 259 mV and 395 mV at a current density of 100 mA/cm2 for HER and OER, respectively. MoSe2-Ni3Se2/NF with a two-electrode system attains a current density of 10 mA/cm2 at 1.60 V. In addition, the overpotential of HER and OER of MoSe2-Ni3Se2/NF within 80000 s and the decomposition voltage of electrocatalytic total water decomposition hardly changed, showing an extremely strong stability. The improvement of MoSe2-Ni3Se2/NF catalytic activity is attributed to the establishment of the multi-phase structure and the optimized inoculation of the multi-component and multi-interface.

Correction to: The transcription factor KLF14 regulates macrophage glycolysis and immune function by inhibiting HK2 in sepsis

Correction to:Cellular&Molecular Immunology https://doi.org/10.1038/s41423-021-00806-5,published online 4 January 2022 In the version of this article initially published,two unintended errors were made during manuscript editing.The corresponding author’s name was misspelled and therefore incorrectly listed as Jingbao Li with the email address lijingbaoshanghai@163.com.

Shanghai Autism Early Development:An Integrative Chinese ASD Cohort

Why Was the Cohort Set Up?Autism spectrum disorder(ASD)is a child neurodevelopmental disorder,the onset of which is generally within 3 years of age,and often leads to lifelong impaired social and cognitive functions,which impose significant mental pressure and economic burdens on the family and society.

Experimental and computational models for tissue-engineered heart valves:a narrative review

Valvular heart disease is currently a common problem which causes high morbidity and mortality worldwide.Prosthetic valve replacements are widely needed to correct narrowing or backflow through the valvular orifice.Compared to mechanical valves and biological valves,tissue-engineered heart valves can be an ideal substitute because they have a low risk of thromboembolism and calcification,and the potential for remodelling,regeneration,and growth.In order to test the performance of these heart valves,various animal models and other models are needed to optimise the structure and function of tissue-engineered heart valves,which may provide a potential mechanism responsible for substantial enhancement in tissue-engineered heart valves.Choosing the appropriate model for evaluating the performance of the tissue-engineered valve is important,as different models have their own advantages and disadvantages.In this review,we summarise the current state-of-the-art animal models,bioreactors,and computational simulation models with the aim of creating more strategies for better development of tissue-engineered heart valves.This review provides an overview of major factors that influence the selection and design of a model for tissue-engineered heart valve.Continued efforts in improving and testing models for valve regeneration remain crucial in basic science and translational researches.Future research should focus on finding the right animal model and developing better in vitro testing systems for tissue-engineered heart valve.