Electronic structure and phase transition engineering in NbS2: Crucial role of van der Waals interactions

Based on first-principles simulations,we revisit the crystal structures,electronic structures,and structural stability of the layered transition metal dichalcogenides(TMDCs)NbS2,and shed more light on the crucial roles of the van der Waals(vdW)interactions.Theoretically calculated results imply that the vdW corrections are important to reproduce the layered crystal structure,which is significant to correctly describe the electronic structure of NbS2.More interestingly,under hydrostatic pressure or tensile strain in ab plane,an isostructural phase transition from two-dimensional layered structure to three-dimensional bulk in the I4/mmm phase has been uncovered.The abnormal structural transition is closely related to the electronic structure instability and interlayer bonding effects.The interlayer Nb-S distances collapse and the interlayer vdW interactions disappear,concomitant with new covalent bond emerging and increasing coordination number.Present work highlights the significance of the vdW interactions,and provides new insights on the unconventional structural transitions in NbS2,which will attract wide audience working in the hectic field of TMDCs.

MAX-DOAS and in-situ measurements of aerosols and trace gases over Dongying,China:Insight into ozone formation sensitivity based on secondary HCHO

This study presents a comprehensive overview of the atmospheric pollutants including Sulfur dioxide(SO_(2)),Nitrogen dioxide(NO_(2)),Formaldehyde(HCHO),Particulate Matter PM;PM_(10):diameter≤10μm,and PM_(2.5):diameter≤2.5μm,and Ozone(O_(3)),over Dongying(Shandong Province)from March-April 2018 and September-October 2019 by employing ground-based Multiple Axis Differential Optical Absorption Spectroscopy(MAX-DOAS)observations along with the in-situ measurements attained by the national air quality monitoring platform.The concentrations of SO_(2)and NO_(2)were under the acceptable level,while both PM_(2.5),and PM_(10)were higher than the safe levels as prescribed by national and international air quality standards.The results depict that 21%of the total observation days were found to be complex polluted days(PM_(2.5)>35μg/m^(3) and O_(3)>160μg/m^(3)).The secondary HCHO was used for accurate analysis of O_(3)sensitivity.A difference of 11.40%and 10%during March-April 2018 and September-October 2019 respectively in O_(3)sensitivity was found between HCHO_(total)/NO_(2)and HCHO_(sec)/NO_(2).The results indicate that primary HCHO have significant contribution in HCHO.O_(3)formation predominantly remained to be in VOC-limited and transitional regime during March-April 2018 and September-October 2019 in Dongying.These results imply that concurrent control of both NO_(x) and VOCs would benefit in ozone reductions.Additionally,the criteria pollutants(PM,SO_(2),and NO_(2))depicted strong correlations with each other except for O_(3)for which weak correlation coefficient was obtained with all the species.This study will prove to be baseline for designing of air pollution control strategies.

Dichloromethane-Induced Poisoning from Acrylic Paint Cleaner-Shenzhen City,Guangdong Province,China,2023

Summary What is already known about this topic?Dichloromethane(DCM)is a colorless and transparent organic solvent that commonly causes poisoning during occupational contact.What is added by this report?Unknown to teachers and students,they were utilizing an acrylic paint cleaner that contained DCM.At the time of the poisoning incident,the art room was occupied beyond its capacity with inadequate local ventilation.The primary cause of the incident was determined to be the students’inhalation of DCM during the cleaning process.What are the implications for public health practice?The unclear composition of environmental cleaning products available for purchase online presents a major obstacle for consumers trying to assess their toxicity.It is imperative that robust regulatory measures and proactive public education campaigns are implemented to mitigate instances of poisoning.

Potentiating CD8^(+) T cell antitumor activity by inhibiting PCSK9 to promote LDLR-mediated TCR recycling and signaling

Metabolic regulation has been proven to play a critical role in T cell antitumor immunity.However,cholesterol metabolism as a key component of this regulation remains largely unexplored.Herein,we found that the low-density lipoprotein receptor(LDLR),which has been previously identified as a transporter for cholesterol,plays a pivotal role in regulating CD8+T cell antitumor activity.Besides the involvement of cholesterol uptake which is mediated by LDLR in T cell priming and clonal expansion,we also found a non-canonical function of LDLR in CD8+T cells:LDLR interacts with the T-cell receptor(TCR)complex and regulates TCR recycling and signaling,thus facilitating the effector function of cytotoxic T-lymphocytes(CTLs).Furthermore,we found that the tumor microenvironment(TME)downregulates CD8+T cell LDLR level and TCR signaling via tumor cell-derived proprotein convertase subtilisin/kexin type 9(PCSK9)which binds to LDLR and prevents the recycling of LDLR and TCR to the plasma membrane thus inhibits the effector function of CTLs.Moreover,genetic deletion or pharmacological inhibition of PCSK9 in tumor cells can enhance the antitumor activity of CD8+T cells by alleviating the suppressive effect on CD8+T cells and consequently inhibit tumor progression.While previously established as a hypercholesterolemia target,this study highlights PCSK9/LDLR as a potential target for cancer immunotherapy as well.

入侵植物与重金属胁迫的相互作用研究进展

全球变化改变了植物群落的分布格局,包括入侵植物,而人为污染可能降低本地植物对入侵植物的抗性。因此,本文总结了近几十年本地植物、入侵植物和植物-土壤生态系统中重金属生物地球化学行为的研究,以加深我们对入侵植物与环境胁迫因子相互作用的认识。我们的研究结合已有文献报道表明:(i)入侵物种对环境胁迫的影响具有异质性,(ii)影响的大小是多变的,(iii)即使在同一影响类型内,影响类型也具有多向性。然而,入侵植物暴露在重金属环境中表现出更强的自我保护机制,对重金属的生物可利用性和毒性有正向或负向的影响。另一方面,由于入侵植物普遍具有较高的耐受性,加之本地植物暴露于有毒重金属污染时具有“逃逸行为”,重金属胁迫环境更有利于植物的成功入侵。但是,对于入侵植物的重金属等元素组成是否与污染地区的本地植物不同,目前尚无共识。因此,在全球范围内对外来入侵植物与本土植物的植物体内、凋落物和土壤污染物含量进行定量比较是今后研究的一个重要方向。

Sulfur mediated heavy metal biogeochemical cycles in coastal wetlands:From sediments,rhizosphere to vegetation

The interactions and mechanisms between sulfur and heavy metals are a growing focus of biogeochemical studies in coastal wetlands.These issues underline the fate of heavy metals bound in sediments or released into the system through sediments.Despite the fact that numerous published studies have suggested sulfur has a significant impact on the bioavailability of heavy metals accumulated in coastal wetlands,to date,no review article has systematically summarized those studies,particularly from the perspective of the three major components of wetland ecosystems(sediments,rhizosphere,and vegetation).The present review summarizes the studies published in the past four decades and highlights the major achievements in this field.Research and studies available thus far indicate that under anaerobic conditions,most of the potentially bioavailable heavy metals in coastal wetland sediments are fixed as precipitates,such as metal sulfides.However,fluctuations in physicochemical conditions may affect sulfur cycling,and hence,directly or indirectly lead to the conversion and migration of heavy metals.In the rhizosphere,root activities and microbes together affect the speciation and transformation of sulfur which in turn mediate the migration of heavy metals.As for plant tissues,tolerance to heavy metals is enhanced by sulfur-containing compounds via promoting a series of chelation and detoxification processes.Finally,to further understand the interactions between sulfur and heavy metals in coastal wetlands,some major future research directions are proposed.

Correction to:Potentiating CD8^(+)T cell antitumor activity by inhibiting PCSK9 to promote LDLR-mediated TCR recycling and signaling

Figure 1.LDLR deficiency hinders the antitumor activity of CD8^(+)T cells.(A)Transcriptional level of genes involved in cholesterol transport in naïve CD8^(+)T cells,CTLs and CD8^(+)TILs(isolated at Day3 or Day7 post CTLs adoptive transfer),(n=4).(B)LDLR expression level on CTLs and CD8^(+)TILs(isolated at Day3 post CTLs adoptive transfer),(n=4).