“四层次、三联动”化学通识课程体系的探索与实践

高等教育兼备广度和深度,化学作为一门中心学科,支撑着其它学科的发展,化学通识课程旨在培养大学生具有清晰的化学逻辑思考力和判断力。浙江大学化学系以推进“新工科、新医科、新农科”的建设为目标,面向全校近50个专业开设了8门通识课程,通过构建大学化学-普通化学(甲)/普通化学(H)-普通化学(乙)-工程化学四层次的课程体系、教师-教学科-学工三联动的全过程管理和全面的助教制度,形成了适合综合性大学以学生成长为中心的化学通识课程新体系,提升了“新工科、新医科、新农科”人才的化学素养和综合分析问题、解决问题的能力。

Two/Quasi-two-dimensional perovskite-based heterostructures:construction,properties and applications

Two-dimensional(2D)/quasi-2D organic-inorganic halide perovskites are regarded as naturally formed multiple quantum wells with inorganic layers isolated by long organic chains,which exhibit layered structure,large exciton binding energy,strong nonlinear optical effect,tunable bandgap via changing the layer number or chemical composition,improved environmental stability,and excellent optoelectronic properties.The extensive choice of long organic chains endows 2D/quasi-2D perovskites with tunable electron-phonon coupling strength,chirality,or ferroelectricity properties.In particular,the layered nature of 2D/quasi-2D perovskites allows us to exfoliate them to thin plates to integrate with other materials to form heterostructures,the fundamental structural units for optoelectronic devices,which would greatly extend the functionalities in view of the diversity of 2D/quasi-2D perovskites.In this paper,the recent achievements of 2D/quasi-2D perovskite-based heterostructures are reviewed.First,the structure and physical properties of 2D/quasi-2D perovskites are introduced.We then discuss the construction and characterizations of 2D/quasi-2D perovskite-based heterostructures and highlight the prominent optical properties of the constructed heterostructures.Further,the potential applications of 2D/quasi-2D perovskite-based heterostructures in photovoltaic devices,light emitting devices,photodetectors/phototransistors,and valleytronic devices are demonstrated.Finally,we summarize the current challenges and propose further research directions in the field of 2D/quasi-2D perovskite-based heterostructures.

Overexpression of Sirt6 ameliorates sleep deprivation induced-cognitive impairment by modulating glutamatergic neuron function

Sleep benefits the restoration of energy metabolism and thereby suppo rts neuronal plasticity and cognitive behaviors.Sirt6 is a NAD+-dependent protein deacetylase that has been recognized as an essential regulator of energy metabolism because it modulates various transcriptional regulators and metabolic enzymes.The aim of this study was to investigate the influence of Sirt6 on cerebral function after chronic sleep deprivation(CSD).We assigned C57BL/6J mice to control or two CSD groups and subjected them to AAV2/9-CMV-EGFP or AAV2/9-CMV-Sirt6-EGFP infection in the prelimbic cortex(PrL).We then assessed cerebral functional connectivity(FC) using resting-state functional MRI,neuron/astrocyte metabolism using a metabolic kinetics analysis;dendritic spine densities using sparse-labeling;and miniature excitato ry postsynaptic currents(mEPSCs) and action potential(AP) firing rates using whole-cell patchclamp recordings.In addition,we evaluated cognition via a comprehensive set of behavioral tests.Compared with controls,Sirt6 was significantly decreased(P<0.05) in the PrL after CSD,accompanied by cognitive deficits and decreased FC between the PrL and accumbens nucleus,piriform cortex,motor co rtex,somatosensory co rtex,olfactory tubercle,insular cortex,and cerebellum.Sirt6 ove rexpression reve rsed CSD-induced cognitive impairment and reduced FC.Our analysis of metabolic kinetics using [1-13C] glucose and [2-13C] acetate showed that CSD reduced neuronal Glu4and GABA2synthesis,which could be fully restored via forced Sirt6 expression.Furthermore,Sirt6 ove rexpression reversed CSD-induced decreases in AP firing rates as well as the frequency and amplitude of mEPSCs in PrL pyramidal neurons.These data indicate that Sirt6 can improve cognitive impairment after CSD by regulating the PrL-associated FC network,neuronal glucose metabolism,and glutamatergic neurotransmission.Thus,Sirt6 activation may have potential as a novel strategy for treating sleep disorder-related diseases.

See the color,see the seed:GmW1 as a visual reporter for transgene and genome editing in soybean

A fast and efficient recognition method of transgenic lines will greatly improve detection efficiency and reduce cost.In this study,we successfully identified the transgenic soybean plants by the color.We isolated a GmW1 gene encoding a flavonoid 3'5'-hydroxylase from a soybean cultivar ZH42(purple flower).We found that purple flowers occurred in the overexpression lines in the Jack and Williams 82 backgrounds(white flower).All plants with purple flowers were positive,and this trait seems stably inherited in the offspring.We have also obtained the editing plants,which were classified into three types according to the different flower colors appeared.We analyzed the phenotype and the homozygous types of the T_1mutants.We also found that a correspondence between flower color and stem color.This study provides a visible color reporter on soybean transformation.It can be quickly and early to identify the transgenic soybean plants by stem color of seedlings,which substantially reduces the amount of labor and cost.

Fairness-Aware Harvested Energy Efficiency Algorithm for IRS-Aided Intelligent Sensor Networks with SWIPT

In this paper,a novel fairness-aware harvested energy efficiency-based green transmission scheme for wireless information and power transfer(SWIPT)aided sensor networks is developed for active beamforming of multiantenna transmitter and passive beamforming at intelligent reflecting surfaces(IRS).By optimizing the active beamformer assignment at the transmitter in conjunction with the passive beamformer assignment at the IRS,we aimtomaximize the minimumharvested energy efficiency among all the energy receivers(ER)where information receivers(IR)are bound to the signal-interference-noise-ratio(SINR)and the maximum transmitted power of the transmitter.To handle the non-convex problem,both semi-definite relaxation(SDR)and block coordinate descent technologies are exploited.Then,the original problem is transformed into two convex sub-problems which can be solved via semidefinite programming.Numerical simulation results demonstrate that the IRS and energy beamformer settings in this paper provide greater system gain than the traditional experimental setting,thereby improving the fairness-aware harvested energy efficiency of the ER.

Precise Synthesis of Acrylate Copolymer via RAFT Polymerization and Its Application

A series of different sequence structure containing stearyl acrylate (SA) and hydroxyethyl acrylate (HEA) copolymer were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. The crystallization property of PHEA-b-PSA, PHEA-b-PSA-b-PHEA, PSA-b-PHEA-b-PSA, PHEA-co-PSA, and PHEA-grad-b-PSA were characterized by Differential Scanning Calorimetry (DSC). The condensed structure of different sequence copolymers were investigated using small-angle X-ray scattering (SAXS). A series of copolymers with different sequence structure were coated on the surface of polyester fabric, which can be found that PHEA-b-PSA-b-PHEA block copolymer has good water repellency.

Distinct synergetic effects in the ozone enhanced photocatalytic degradation of phenol and oxalic acid with Fe^(3+)/TiO_2 catalyst

In this work. phenol and oxalic acid （OA） degradation in an ozone and photocatalysis integrated process was intensively conducted with Fe3 ＋/TiO2 catalyst. The ferrioxalate complex formed between Fe3＋ and oxalate accelerated the removal of OA in the ozonation, photolysis and photocatalytic ozonation process, for its high reactivity with ozone and UV. Phenol was degraded in ozonation and photolysis with limited TOC removal rates, but much higher TOC removal was achieved in photocatalytic ozonation due to the generation of-OH. The sequence of UV light and ozone in the sequential process also influences the TOC removal, and ozone is very powerful to oxidize intermediates catechol and hydroquinone to maleic acid. Fenton or photo-Fenton reactions only played a small part in Fe3＋/TiO2 catalyzed processes, because Fe＋ was greatly reduced but not regenerated in many cases. The synergetic effect was found to be highly related with the property of the target pollutants. Fe3 ＋/TiO2 catalyzed system showed the highest ability to destroy organics, but the TiO2 catalyzed system showed little higher synergy.

Effects of free-air CO_2 enrichment on adventitious root development of rice under low and normal soil nitrogen levels

Free air CO2 enrichment(FACE) and nitrogen(N) have marked effects on rice root growth,and numerical simulation can explain these effects. To further define the effects of FACE on root growth of rice, an experiment was performed, using the hybrid indica cultivar Xianyou63. The effects of increasing atmospheric CO2 concentration [CO2], 200 μmol mol-1higher than ambient, on the growth of rice adventitious roots were evaluated, with two levels of N: low(LN, 125 kg ha-1) and normal(NN, 250 kg ha-1). The results showed a significant increase in both adventitious root number(ARN) and adventitious root length(ARL) under FACE treatment. The application of nitrogen also increased ARN and ARL, but these increases were smaller than that under FACE treatment. On the basis of the FACE experiment, numerical models for rice adventitious root number and length were constructed with time as the driving factor. The models illustrated the dynamic development of rice adventitious root number and length after transplanting, regulated either by atmospheric [CO2] or by N application.The simulation result was supported by statistical tests comparing experimental data from different years, and the model yields realistic predictions of root growth. These results suggest that the models have strong predictive potential under conditions of atmospheric [CO2] rises in the future.

Macro-and Micro-physical Characteristics of Different Parts of Mixed Convective-stratiform Clouds and Differences in Their Responses to Seeding

This study investigates the cloud macro-and micro-physical characteristics in the convective and stratiform regions and their different responses to the seeding for mixed convective-stratiform clouds that occurred in Shandong province on 21 May 2018,based on the observations from the aircraft,the Suomi National Polar-Orbiting Partnership(NPP)satellite,and the high-resolution Himawari-8(H8)satellite.The aircraft observations show that convection was deeper and radar echoes were significantly enhanced with higher tops in response to seeding in the convective region.This is linked with the conversion of supercooled liquid droplets to ice crystals with released latent heat,resulting in strengthened updrafts,enhanced radar echoes,higher cloud tops,and more and larger precipitation particles.In contrast,in the stratiform cloud region,after the Silver Iodide(AgI)seeding,the radar echoes become significantly weaker at heights close to the seeding layer,with the echo tops lowered by 1.4–1.7 km.In addition,a hollow structure appears at the height of 6.2–7.8 km with a depth of about 1.6 km and a diameter of about 5.5 km,and features such as icing seeding tracks appear.These suggest that the transformation between droplets and ice particles was accelerated by the seeding in the stratiform part.The NPP and H8 satellites also show that convective activity was stronger in the convective region after seeding;while in the stratiform region,a cloud seeding track with a width of 1–3 km appears 10 km downstream of the seeding layer 15 minutes after the AgI seeding,which moves along the wind direction as width increases.

Coastal Environmental Changes and Management in China in the Context of Global Changes and Human Activities

Coastal zone is the complex area with intense sea-land interaction. There are various types, complex environments and developed economy in coastal area of China. Under the influence of global change and human activities, the ecosystem of coastal zone is vulnerable and has sensitive response to environment changes. The environmental problems of sea-level rising have attached close attention by countries all over the world. As far as regions concerned, relative sea-level rising is more important than theoretical sea-level rising. The relative sea-level rising has resulted in series of environment disasters in coastal area of China, such as coastal erosion, seawater invasion, and floods in coastal lowlands, etc. The flux of sediments transported by rivers into sea is the main material source of marine pollution. The human activities are controlling factors of variations in river sediment loads. Under the influence of high strength development in the upstream region, the results are that the reduction of seagoing sediments in main rivers of China, and damage of coastal material balance. Land-based pollution is the main source of marine pollution. With rapid economic development in China s eastern coastal, pollutants flux into sea increase gradually. The results are that the environmental quality and seawater quality of marine have being deteriorated and pollution is serious increasingly. To meet the land demand of industrialization and urbanization, the sea reclamation has become an effective means to alleviate the contradiction between human and land in coastal area of China. This leads to large-scale reduction of coastal wetland area, and the heavy losses of ecological service value of coastal wetland. To face the environmental changes in coastal area of China and solve the contradiction among population, resources, environment, development, it is required to set up the system concept of man-land-sea relationship, so as to achieve sustainable development. The feasible measures include improving coastal management system, strengthening integrated basin management, attaching importance to construction of the coastal environment engineering, and raising the environmental monitoring and early warning level.

创业退出:研究述评与未来展望

健康的创业生态不仅需要鼓励创业进入,更需要畅通退出渠道。创业退出是创业者离开自己创建的企业,从企业所有权或决策权中逐渐脱离的过程。作为创业过程的重要环节,创业退出不仅在个体层面上决定了创业者的试错成本,在组织层面上影响企业的稳定与发展,也对创业资源在不同行业、地区的流动和配置存在重要影响。然而,既有研究针对创业退出的关注尚不充分,存在以下研究缝隙:概念界定模糊、研究问题零散、本土研究的理论价值不足等。通过对相关文献的系统回顾,本文厘清了创业退出的定义及内涵,并从前因、策略和影响等方面构建了创业退出研究的理论框架。最后,基于当前的研究现状与局限,本文从研究主题拓展、本土理论构建、跨学科方法应用三个方面提出了未来研究方向。

肿瘤模型研究进展及应用

肿瘤模型研究是肿瘤领域的热点。肿瘤模型为肿瘤机制研究及临床转化应用提供了基础保障。肿瘤细胞系和异种移植物是目前常用的研究模型,但因细胞系缺乏原始肿瘤的异质性,异种移植物培养周期长、成瘤率低,应用存在一定局限性。肿瘤3D培养模型包括肿瘤悬浮球和肿瘤类器官模型,模拟了原始肿瘤的生长环境,且很好地模拟了细胞间及细胞-基质间的相互作用。肿瘤类器官作为新兴的肿瘤研究平台,具有易于构建、成瘤率高,并能长期传代和冷冻保存等优点,在很大程度上维持原始肿瘤的结构、遗传特性和肿瘤内异质性,在肿瘤研究中具有巨大潜力。

Changes in Sedimentation Rate of Tidal Flat and Environmental Significance at Qidong Foreland of the Yangtze Estuary

The sedimentation rate is an important environmental parameter to understand the evolution of coastal geomorphology. The tidal flat around Qidong foreland is located in the junction between Yangtze Estuary and Jiangsu coast,where the land-ocean interactions are strong and highly sensitive to environmental changes. The QDZ-1 core sediments collected at Qidong foreland was analyzed for137 Cs dating and grain size.The results showed that silt is the main sedimentary type with a trend of gradually fining from the bottom to the top,conforming to the sedimentation characteristic of the silt muddy tidal flat. The sedimentation rate could be divided into three distinct stages: 1963 to 1986 was 2. 61 cm/yr,1963 to 2011 was 1. 82 cm/yr,and 1986 to 2011 was 1. 10 cm/yr. Based on these,further explanation was made for the significance of environmental changes. According to the estimation of sedimentation rate,the impact of extreme environmental change was reflected by the sudden increase in sand proportion at the depth of 172. 5 cm. Since the introduction of Spartina alterniflora in the 1970 s,it has played an important role in tidal flat development. The tidal flat has a high sedimentary rate during this time. With continuous accretion of the tidal flat,low tidal flat turns to high tidal flat,the sedimentation rate gradually declines,and tidal flat sedimentation appears.

Estimation of Remote Sensing and Analysis of Temporal and Spatial Distribution of Grassland LAI

To estimate the leaf area index(LAI)in large areas,this paper analyzes the relationships between normalized difference vegetation index(NDVI)and the grassland LAI based on MODIS data in the southern grassy mountains and slopes of China.By using nonlinear fitting equation we constructed the basic estimation model of grassland LAI with NDVI as the independent variable and introduced precipitation and temperature as regulatory factors.The model was validated with observed data in different years and the results showed that there was a good correlation between the simulated and observed LAI value with a statistically significant level of R2.RMSE was 0.302 and RRMSE was 0.154.It was also found that the spatial distribution of grassland LAI in south China showed a remarkable zonal characterization,and temporal distribution showed a single peak curve.These results provided a theoretical basis for the effective management of southern grassland resources and the carbon sink estimation of the nationwide grasslands.

Surface engineering of carbon dots for highly sensitive α-glucosidase assay and inhibition evaluation

Monitoringα-glucosidase(α-Glu)activity is of great significance for the early diagnosis of typeⅡdiabetes.Here the blue fluorescent carbon dots(CDs)were integrated with two different recognizing molecules,β-cyclodextrin and phenylboronic acid,for assembling a multifunctional CDs(mCDs)nanoplatform for sensitively analyzingα-Glu and its inhibitors.The hydrolyzed product of 4-nitrophenyl-α-D-glucopyranoside(α-Glu substrate),p-nitrophenol,could efficiently quench the fluorescence of mCDs due to its cooperative molecular recognition withβ-cyclodextrin and phenylboronic acid.The mCDs could be utilized for the detection ofα-Glu activity with the limit of detection of 0.030 U/L.Moreover,the presentα-Glu detection platform revealed a high selectivity,and other natural enzymes showed scarcely any effect on the present mCDs system.The proposed method could be facilely used to screenα-Glu inhibitors with satisfying performance.The rational mCDs is expected to supplement more comprehensive biosensing platforms for highly sensitive and specific recognition of disease-relevant biomarkers with clinical importance.

Topology-based multi-jammer localization in wireless networks

Jamming attacks and unintentional radio interference are some of the most urgent threats harming the dependability of wireless communication and endangering the successful deployment of pervasive applications built on top of wireless networks.Unlike the traditional approaches focusing on developing jamming defense techniques without considering the location of jammers,we take a different viewpoint that the jammers'position should be identified and exploited for building a wide range of defense strategies to alleviate jamming.In this paper,we address the problem of localizing multiple jamming attackers coexisting in wireless networks by leveraging the network topology changes caused by jamming.We systematically analyze the jamming effects and develop a framework that can partition network topology into clusters and can successfully estimate the positions of multiple jammers even when their jamming areas are overlapping.Our experiments on a multi-hop network setup using MicaZ sensor nodes validate the feasibility of real-time collection of network topology changes under jamming and our extensive simulation results demonstrate that our approach is highly effective in localizing multiple attackers with or without the prior knowledge of the order that the jammers are turned on.

Dronedarone inhibits the proliferation of esophageal squamous cell carcinoma through the CDK4/CDK6-RB1 axis in vitro and in vivo

Treatment options for patients with esophageal squamous cell carcinoma(ESCC)often result in poor prognosis and declining health-related quality of life.Screening FDA-approved drugs for cancer chemoprevention is a promising and cost-efficient strategy.Here,we found that dronedarone,an antiarrhythmic drug,could inhibit the proliferation of ESCC cells.Moreover,we conducted phosphorylomics analysis to investigate the mechanism of dronedarone-treated ESCC cells.Through computational docking models and pull-down assays,we demonstrated that dronedarone could directly bind to CDK4 and CDK6 kinases.We also proved that dronedarone effectively inhibited ESCC proliferation by targeting CDK4/CDK6 and blocking the G0/G1 phase through RB1 phosphorylation inhibition by in vitro kinase assays and cell cycle assays.Subsequently,we found that knocking out CDK4 and CDK6 decreased the susceptibility of ESCC cells to dronedarone.Furthermore,dronedarone suppressed the growth of ESCC in patient-derived tumor xenograft models in vivo.Thus,our study demonstrated that dronedarone could be repurposed as a CDK4/6 inhibitor for ESCC chemoprevention.

The molecular and cellular choreography of early mammalian lung development

Mammalian lung development starts from a specific cluster of endodermal cells situated within the ventral foregut region.With the orchestrating of delicate choreography of transcription factors,signaling pathways,and cell–cell communications,the endodermal diverticulum extends into the surrounding mesenchyme,and builds the cellular and structural basis of the complex respiratory system.This review provides a comprehensive overview of the current molecular insights of mammalian lung development,with a particular focus on the early stage of lung cell fate differentiation and spatial patterning.Furthermore,we explore the implications of several congenital respiratory diseases and the relevance to early organogenesis.Finally,we summarize the unprecedented knowledge concerning lung cell compositions,regulatory networks as well as the promising prospect for gaining an unbiased understanding of lung development and lung malformations through stateof-the-art single-cell omics.

床旁超声评价淡水淹溺性心脏停搏复苏后肺损伤一例

患者,青年男性,25岁,因4h前溺水于2021年8月19日下午到解放军总医院第三医学中心急诊科就诊。患者当日上午在深约6m的淡水游泳池(池水温度27~30℃)初学游泳2h后溺水,沉入池底约3min后被人救起,即刻患者面色青紫、呼之无应答,无呼吸及心跳搏动,立即给予心肺复苏,约持续40s后心肺复苏成功。

Cross-sectional rainfall observation on the central-western Tibetan Plateau in the warm season:System design and preliminary results

The central and western Tibetan Plateau(CWTP)is characterized by harsh environment and strong interactions among the spheres of earth as well as significant changes in climate and water cycles over the past four decades.The lack of precipitation observations is a bottleneck for the study of land surface processes in this region.Over the past six years,we have designed and established two observation transects across the south-north and the west-east in this region to obtain hourly rainfall data during the warm season(May-September).The south-north transect extends from Yadong Valley on the southern slope of the Himalayas to Shuanghu County in the hinterland of the plateau,with a total of 31stations;the west-east transect extends from Shiquanhe in the west to Naqu in the central TP,with a total of 22 stations.The observation dataset has been applied to clarify the spatiotemporal characteristics of precipitation in the CWTP,to evaluate the quality of typical gridded precipitation products,to support the development of regional climate models,and to reveal the processes of summertime lake-air interactions.The observation dataset has been released in the National Tibetan Plateau Data Center.