Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement

Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.

YOLO-RLC:An Advanced Target-Detection Algorithm for Surface Defects of Printed Circuit Boards Based on YOLOv5

Printed circuit boards(PCBs)provide stable connections between electronic components.However,defective printed circuit boards may cause the entire equipment system to malfunction,resulting in incalculable losses.Therefore,it is crucial to detect defective printed circuit boards during the generation process.Traditional detection methods have low accuracy in detecting subtle defects in complex background environments.In order to improve the detection accuracy of surface defects on industrial printed circuit boards,this paper proposes a residual large kernel network based on YOLOv5(You Only Look Once version 5)for PCBs surface defect detection,called YOLO-RLC(You Only Look Once-Residual Large Kernel).Build a deep large kernel backbone to expand the effective field of view,capture global informationmore efficiently,and use 1×1 convolutions to balance the depth of the model,improving feature extraction efficiency through reparameterization methods.The neck network introduces a bidirectional weighted feature fusion network,combined with a brand-new noise filter and feature enhancement extractor,to eliminate noise information generated by information fusion and recalibrate information from different channels to improve the quality of deep features.Simplify the aspect ratio of the bounding box to alleviate the issue of specificity values.After training and testing on the PCB defect dataset,our method achieved an average accuracy of 97.3%(mAP50)after multiple experiments,which is 4.1%higher than YOLOv5-S,with an average accuracy of 97.6%and an Frames Per Second of 76.7.The comparative analysis also proves the superior performance and feasibility of YOLO-RLC in PCB defect detection.

Impact of oxygen incorporation on interface optimization and defect suppression for efficiency enhancement in Cu_(2)ZnSn(S,Se)_(4)solar cells

Kesterite Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)solar cells suffer from severe carrier recombination,limiting the photovoltaic performance.Unfavorable energy band alignment at the p-n junction and defective front interface are two main causes.Herein,oxygen incorporation in CZTSSe via absorber air-annealing was developed as a strategy to optimize its surface photoelectric property and reduce the defects.With optimized oxygen incorporation conditions,the carrier separation and collection behavior at the front interface of the device is improved.In particular,it is found that oxygen incorporated absorber exhibits increased band bending,larger depletion region width,and suppressed absorber defects.These indicate the dynamic factors for carrier separation become stronger.Meanwhile,the increased potential difference between grain boundaries and intra grains combined with the decreased concentration of interface deep level defect in the absorber provide a better path for carrier transport.As a consequence,the champion efficiency of CZTSSe solar cells has been improved from 9.74%to 12.04%with significantly improved open-circuit voltage after optimized air-annealing condition.This work provides a new insight for interface engineering to improve the photoelectric conversion efficiency of CZTSSe devices.

Linear magnetoresistance and structural distortion in layered SrCu_(4-x)P_(2) single crystals

We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magnetoresistance without any sign of saturation with a magnetic field up to 30T. We also observe a phase transition with significant anomalies in resistivity and heat capacity at T_(p)~140 K. Thermal expansion measurement reveals a subtle lattice parameter variation near Tp, i.e.,?L_(c)/L_(c)~0.062%. The structural characterization confines that there is no structure transition below and above T_(p). All these results suggest that the nonmagnetic transition of SrCu_(4-x)P_(2) could be associated with structural distortion.

Causal relationship between circulating vitamin C and 25-hydroxyvitamin D concentrations and common mental disorders-a Mendelian randomization study

Mental disorders seriously affect people’s health and social stability.This Mendelian randomization(MR)study was designed to investigate the causal relationship between circulating vitamin C(VC)or 25-hydroxyvitamin D(25(OH)D)levels and mental disorders.The data used for the MR analysis were derived from the summary genome-wide association studies(GWAS)database for VC and 25(OH)D and from the Finn Gen consortium for fourteen mental disorders.Based on the inverse variance weighted(IVW)method,we found a potential causal association between circulating VC and anxiety disorders(IVW:OR=1.139,95%CI:1.023-1.269,P=0.018).However,no causal association was found between VC or 25(OH)D and other mental disorders(P>0.05).In the reverse MR analysis,individuals with Alzheimer’s disease was causally associated with higher concentrations of circulating VC(P=0.012),while individuals with anxiety disorders had a negative association between the concentrations of 25(OH)D(P=0.012).However,the current evidence does not support a causal relationship between VC or 25(OH)D and other mental disorders.In addition,there was no causal association between circulating VC and 25(OH)D(P>0.05).Future studies are needed to confirm these findings and to elucidate the mechanisms of potential causality.

An Experimental Analysis of Gas-Liquid Flow Breakdown in a T-Junction

When a gas-liquid two-phase flow(GLTPF)enters a parallel separator through a T-junction,it generally splits unevenly.This phenomenon can seriously affect the operation efficiency and safety of the equipment located downstream.In order to investigate these aspects and,more specifically,the so-called bias phenomenon(all gas and liquid flowing to one pipe,while the other pipe is a liquid column that fluctuates up and down),laboratory experiments were carried out by using a T-junction connected to two parallel vertical pipes.Moreover,a GLTPF prediction model based on the principle of minimum potential energy was introduced.The research results indicate that this model can accurately predict the GLTPF state in parallel risers.The boundary of the slug flow and the churn flow in the opposite pipe can be predicted.Overall,according to the results,the pressure drop curves of the two-phase flow in the parallel risers are basically the same when there is no bias phenomenon,but the pressure drop in the parallel riser displays a large deviation when there is a slug flow-churn flow.Only when the parallel riser is in a state of asymmetric flow and one of the risers produces churn flow,the two-phase flow is prone to produce the bias phenomenon.

Spatial Dynamics of Chickenpox Outbreaks in Rapidly Developing Regions:Implications for Global Public Health

Objective The occurrence of chickenpox in rapidly developing areas poses substantial seasonal risk to children.However,certain factors influencing local chickenpox outbreaks have not been studied.Here,we examined the relationship between spatial clustering,heterogeneity of chickenpox outbreaks,and socioeconomic factors in Southern China.Methods We assessed chickenpox outbreak data from Southern China between 2006 and 2021,comprising both relatively fast-growing parts and slower sub-regions,and provides a representative sample of many developing regions.We analyzed the spatial clustering attributes associated with chickenpox outbreaks using Moran’s I and local indicators of spatial association and quantified their socioeconomic determinants using Geodetector q statistics.Results There were significant spatial heterogeneity in the risk of chickenpox outbreaks,with strong correlations between chickenpox risk and various factors,particularly demographics and living environment.Furthermore,interactive effects among specific are factors,such as population density and per capita residential building area,percentage of households with toilets,percentage of rental housing,exhibited q statistics of 0.28,0.25,and 0.24,respectively.Conclusion This study provides valuable insights into the spatial dynamics of chickenpox outbreaks in rapidly developing regions,revealing the socioeconomic factors affecting disease transmission.These implications extend the formulation of effective public health strategies and interventions to prevent and control chickenpox outbreaks in similar global contexts.

Progress and Prospects of the Natural Restoration of Damaged Vegetation after the Earthquake

Vegetation plays an important role in soil and water conservation, water conservation and carbon sequestration of an ecosystem. The restoration of damaged vegetation is of great significance to the maintenance of species diversity and the restoration of the regional ecological environment. It is also one of the most effective measures to improve the fragile ecosystem. This paper summarizes the research results from decades of damaged vegetation recovery in the process of vegetation recovery, the main driving factor and the restoration mode.

针对鼠伤寒沙门氏菌致病性岛Ⅲ筛选中药活性成分作为鼠伤寒沙门氏菌潜在毒力抑制剂

目的:筛选中药活性成分作为鼠伤寒沙门氏菌致病性岛III(Salmonella pathogenicity island III,SPI-3)潜在毒力抑制剂。方法:通过分子对接技术明确中药成分与SPI-3中的MgtC蛋白的潜在结合关系。使用β-半乳糖苷酶测定法评估中药成分对mgtC转录的影响。最后,通过评估细菌生长曲线和关键代谢基因的转录水平研究药物对细菌生长的影响。结果:所有27个候选中药成分均显示出与MgtC结合的潜力。阿魏酸、对羟基肉桂酸、牛蒡子苷和掌叶防己碱使mgtC的转录活性降低了15%以上。这四个成分对mgtC转录的最低抑制浓度分别为:阿魏酸16μM;对羟基肉桂酸40μM;牛蒡子苷80μM;掌叶防己碱160μM。此外,我们证实这四种成分均未抑制细菌生长。结论:在本研究中,我们建立了一种基于β-半乳糖苷酶测定法的鼠伤寒沙门氏菌毒力抑制剂筛选方法。以SPI-3为靶标,筛选了27种中药成分,发现有4种对鼠伤寒沙门氏菌毒力具有潜在的强效抑制作用。这为未来从草药中开发新型抗生素提供了先导化合物。这种方法也可用于筛选其他致病菌的毒力抑制剂。

The relationships between maize(Zea mays L.)lodging resistance and yield formation depend on dry matter allocation to ear and stem

Lodging is a critical constraint to yield increase.There appear to be tradeoffs between yield formation and lodging resistance in maize.Hypothetically,it is feasible to reduce lodging risk as well as increase grain yield by optimizing dry-matter allocation to different organs under different environments.A three-year field experiment was conducted using four maize cultivars with differing lodging resistances and five growing environments in 2018–2020.Lodging-susceptible(LS)cultivars on average yielded more than lodging-resistant(LR)cultivars when lodging was not present.The yield components kernel number per ear(KN)and thousand-kernel weight(TKW)were both negatively correlated with lodging resistance traits(stalk bending strength,rind penetration strength,and dry matter weight per internode length).Before silking,the LR cultivar Lishou 1(LS1)transported more assimilates to the basal stem,resulting in a thicker basal stem,which reduced dry matter allocation to the ear and in turn KN.The lower KN of LS1 was also due partly to the lower plant height(PH),which increased lodging resistance but limited plant dry matter production.In contrast,the LS cultivars Xianyu 335(XY335)and Xundan 20(XD20)produced and allocated more photoassimilates to ears,but limited dry matter allocation to stems.After silking,LS cultivars showed higher TKW than LR cultivars as a function of high photoassimilate productivity and high assimilate allocation to the ear.The higher lodging resistance of LS1 was due mainly to the greater assimilate allocation to stem after silking and lower PH and ear height(EH).High-yielding and high-LR traits of Fumin(FM985)were related to optimized EH and stem anatomical structure,higher leaf productivity,low assimilate demand for kernel formation,and assimilate partitioning to ear.A high presilking temperature accelerated stem extension but reduced stem dry matter accumulation and basal stem strength.Post-silking temperature influences lodging resistance and yield more than other environmental factors.These results will be useful in understanding the tradeoffs between KN,KW,and LR in maize and environmental influences on these tradeoffs.

Effect of different process conditions on the physicochemical and antimicrobial properties of plasma-activated water

The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed that increasing the processing time and power,and decreasing generated water volume,could cause an increase in the redox potential,conductivity,and temperature of PAW,and a decrease in its pH.A slower dissipation of the reactive oxygen and nitrogen species in PAW was found on storage at 4℃in a sealed conical flask than on storage at room temperature.The inactivation ability of plasma-activated lactic acid(LA)to Listeria monocytogenes(L.monocytogenes)and Pseudomonas aeruginosa(P.aeruginosa)was higher than that of PAW or LA alone under the same experimental conditions.The results of this study may provide theoretical information for the application of PAW as a potential antimicrobial agent in the future.

Improvement of Binocular Reconstruction Algorithm for Measuring 3D Pavement Texture Using a Single Laser Line Scanning Constraint

The dense and accurate measurement of 3D texture is helpful in evaluating the pavement function.To form dense mandatory constraints and improve matching accuracy,the traditional binocular reconstruction technology was improved threefold.First,a single moving laser line was introduced to carry out global scanning constraints on the target,which would well overcome the difficulty of installing and recognizing excessive laser lines.Second,four kinds of improved algorithms,namely,disparity replacement,superposition synthesis,subregion segmentation,and subregion segmentation centroid enhancement,were established based on different constraint mechanism.Last,the improved binocular reconstruction test device was developed to realize the dual functions of 3D texture measurement and precision self-evaluation.Results show that compared with traditional algorithms,the introduction of a single laser line scanning constraint is helpful in improving the measurement’s accuracy.Among various improved algorithms,the improvement effect of the subregion segmentation centroid enhancement method is the best.It has a good effect on both overall measurement and single pointmeasurement,which can be considered to be used in pavement function evaluation.

子痫前期患者认知功能下降与血清β淀粉样蛋白1-42的相关性研究

目的:研究子痫前期(PE)患者、妊娠健康对照(PHC)和非妊娠健康对照(NPHC)认知功能状态以及血清β淀粉样蛋白1-42(Aβ1-42)水平,探讨Aβ1-42作为认知功能损害血清生物学标志物的可行性。方法:纳入65例PE患者,48例NPHC,30例PHC。使用标准化蒙特利尔量表(MoCA)评估受试者认知功能状态,使用酶联免疫吸附试验(ELISA)测定血清Aβ1-42蛋白水平。采用单因素方差分析法和秩和检验法比较三组受试者血清Aβ1-42蛋白水平。采用Spearman双变量相关分析法探究Aβ1-42蛋白与MoCA分值的相关性。通过受试者工作特征(ROC)曲线获取血清Aβ1-42蛋白浓度的曲线下面积(AUC)来预测受试者的认知水平,并与MoCA相比较。结果:PE患者MoCA得分较血压正常的健康孕妇低,差异具有统计学意义(P<0.05)。PE患者中血清Aβ1-42蛋白水平均高于NPHC和PHC(P<0.05)。在妊娠女性(PE组+PHC组)中,血清Aβ1-42水平与MoCA分值呈负线性相关(r=-0,218,P<0.05)。血清Aβ1-42蛋白具有预测妊娠期女性认知功能状态的能力(AUC=0.7807)。结论:PE患者在妊娠期间已出现认知功能下降,血清Aβ1-42蛋白水平可以无创评估PE患者认知功能,可作为评估PE患者认知功能损害的血清生物学标志物。

High-pressure new phases of V–N compounds

The high-pressure diagram of V–N compounds is enriched by proposed seven new stable high-pressure phases.The P-1-VN_4with the armchair N-rich structure may be quenched to ambient conditions.The formed N–N covalent bond plays an important role for the structural stability of N-chain.The charge transfer results in a V–N ionic bond interaction,which further improves the stability of N-chain structure.The P-1-VN_4,P4mnc-VN_8,and Immm-VN_(10)with the outstanding detonation properties have potential application in explosive field.

Magnetic and magnetotransport properties of layered TaCoTe_(2) single crystals

We present the synthesis of TaCoTe_(2) single crystals and a systematic investigation of the physical properties of bulk crystals and thin flakes.The crystal shows a semiconducting behavior with temperature decreasing from room temperature and turns to a metallic behavior below 38 K.When the magnetic field is applied,the temperature-dependent resistivity curves show an upturn below 10 K.Furthermore,we find that the TaCoTe_(2) single crystal can be easily exfoliated from the bulk crystal by the micromechanical exfoliation method.Our measurements suggest that the nanoflakes have properties similar to those of the bulk crystal when the thickness is lowered to 18 nm.

Cerium-promoted conversion of dinitrogen into high-energy-density material CeN_(6) under moderate pressure

Synthesis pressure and structural stability are two crucial factors for highly energetic materials,and recent investigations have indicated that cerium is an efficient catalyst for N2 reduction reactions.Here,we systematically explore Ce–N compounds through first-principles calculations,demonstrating that the cerium atom can weaken the strength of the N≡N bond and that a rich variety of cerium polynitrides can be formed under moderate pressure.Significantly,P1-CeN_(6) possesses the lowest synthesis pressure of 32 GPa among layered metal polynitrides owing to the strong ligand effect of cerium.The layered structure of P1-CeN_(6) proposed here consists of novel N_(14) ring.To clarify the formation mechanism of P1-CeN_(6),the reaction path Ce+3N2→trans-CeN_(6)→P1-CeN_(6) is proposed.In addition,P1-CeN_(6) possesses high hardness(20.73 GPa)and can be quenched to ambient conditions.Charge transfer between cerium atoms and N_(14) rings plays a crucial role in structural stability.Furthermore,the volumetric energy density(11.20 kJ/cm^(3))of P1-CeN_(6) is much larger than that of TNT(7.05 kJ/cm^(3)),and its detonation pressure(128.95 GPa)and detonation velocity(13.60 km/s)are respectively about seven times and twice those of TNT,and it is therefore a promising high-energy-density material.

非小细胞肺癌PD-1/PD-L1的表达与EGFR突变相关性研究

背景与目的肺癌的治疗模式以表皮生长因子受体酪氨酸激酶抑制剂(epidermal growth factor receptortyrosine kinase inhibitors, EGFR-TKIs)作为EGFR突变的非小细胞肺癌(non-small cell lung cancer, NSCLC)患者一线治疗;同时以程序性死亡受体1(programmed death receptor 1, PD-1)及其配体(programmed death receptor ligand 1,PD-L1)抑制剂为代表的免疫检查点抑制剂(immune checkpoint inhibitors,ICIs)的免疫治疗在肺癌治疗中疗效显著。本研究旨在探讨PD-1和PD-L1在NSCLC中的表达及其与临床病理特征、EGFR突变之间的关系。方法采用免疫组化方法检测127例NSCLC PD-1和PD-L1蛋白表达,同时用定量聚合酶链反应(quantitative polymerase chain reaction,qPCR)检测EGFR基因突变,分析其与临床病理特征之间的关系,研究PD-1、PD-L1表达之间以及其与EGFR突变的关系。结果 NSCLC肿瘤细胞及肿瘤浸润免疫细胞PD-1阳性表达53.5%(68/127),肿瘤细胞PD-L1表达57.5%(73/127),PD-1和PD-L1的表达在低分化癌、临床分期Ⅰ期+Ⅱ期明显高于高中分化癌、Ⅲ期+Ⅳ期(均P<0.05);EGFR突变率为46.5%(59/127),EGFR突变的患者中女性、无吸烟史、腺癌、高中分化组分别高于男性、吸烟史、鳞癌、低分化组患者(均P<0.05);NSCLC患者PD-L1与PD-1蛋白表达存在一致性(kappa=0.107,5, P=0.487),EGFR突变与PD-1、PD-L1表达存在负相关关系(Φ=-0.209,Φ=-0.221,均P<0.05);对NSCLC患者随访,在<65岁、腺癌、高中分化癌、PD-L1表达的患者中位总生存期分别高于≥65岁、鳞癌、低分化癌、PD-L1不表达患者(均P<0.05)。PD-L1低表达患者中位生存期明显高于高表达患者(P=0.04)。结论参照《非小细胞肺癌PD-L1免疫组织化学检测规范中国专家共识》检测非小细胞肺癌PD-L1表达,筛选出抗PD-1/PD-L1治疗的优势人群;同时检测出EGFR突变的患者,并且EGFR突变与PD-1、PD-L1表达存在负相关关系,依据PD-L1表达和EGFR突变状态,可能使NSCLC患者在的个体化治疗中获益,同时65岁以下、腺癌、高中分化、PD-L1低表达的患者有相对好的预后,为NSCLC预后评估提供参考。

单极脉冲法沉积聚3,4-乙烯二氧噻吩及其电容性能

聚3,4-乙烯二氧噻吩(PEDOT)因具有非常高的离子电导率而被广泛研究。文中以EDOT为单体,采用单极脉冲法在不锈钢片基底上制备了PEDOT膜电极。考察了不同脉冲参数对PEDOT膜超级电容的影响。通过扫描电子显微镜、傅里叶变换红外光谱表征PEDOT涂覆的不锈钢电极,确认了PEDOT由不规则的虚球体堆积成褶皱状结构,证实了Cl O4-成功掺杂于PEDOT膜中;通过循环伏安法、恒电流充电/放电和电化学阻抗谱得到:PEDOT电极展示出良好的比电容(128.64 F/g)、倍率性能和稳定性(循环2000次保留率达71.26%)。对于低成本、高性能的能量存储应用显示出相当大的潜力。

Microbial diversity in cold seep sediments from the northern South China Sea

South China Sea （SCS） is the largest Western Pacific marginal sea. However, microbial studies have never been performed in the cold seep sediments in the SCS. In 2004, ＂SONNE＂ 177 cruise found two cold seep areas with different water depth in the northern SCS. Haiyang 4 area, where the water depth is around 3000 m, has already been confirmed for active seeping on the seafloor, such as microbial mats, authigenic carbonate crusts and bivalves. We investigated microbial abundance and diver- sity in a 5.55-m sediment core collected from this cold seep area. An integrated approach was employed including geochemistry and 16S rRNA gene phylogenetic analyses. Here, we show that microbial abun- dance and diversity along with geochemistry profiles of the sediment core revealed a coupled reaction between sulphate reduction and methane oxidation. Acridine orange direct count results showed that microbial abundance ranges from 105 to 106 cells/g sediment （wet weight）. The depth-related variation of the abundance showed the same trend as the methane concentration profile. Phylogenetic analysis indicated the presence of sulphate-reducing bacteria and anaerobic methane-oxidizing archaea. The diver- sity was much higher at the surface, but decreased sharply with depth in response to changes in the geochemical conditions of the sediments, such as methane, sulphate concentration and total organic carbon. Marine Benthic Group B, Chloroflexi and JS1 were predominant phylotypes of the archaeal and bacterial libraries, respectively.

PKM2 promotes reductive glutamine metabolism

Objective:Pyruvate kinases M(PKM),including the PKM1 and PKM2 isoforms,are critical factors in glucose metabolism.PKM2promotes aerobic glycolysis,a phenomenon known as"the Warburg effect".The purpose of this study was to identify the roles of PKM2 in regulating cellular metabolism.Methods:The CRISPR/Cas9 system was used to generate the PKM-knockout cell model to evaluate the role of PKM in cellular metabolism.Lactate levels were measured by the Vitros LAC slide method on an autoanalyzer and glucose levels were measured by the autoanalyzer AU5800.The metabolism of ^(13)C_6-glucose or ^(13)C_5-glutamine was evaluated by liquid chromatography/mass spectrometry analyses.The effects of PKM on tumor growth were detected in vivo in a tumor-bearing mouse model.Results:We found that both PKM1 and PKM2 enabled aerobic glycolysis,but PKM2 converted glucose to lactate much more efficiently than PKM1.As a result,PKM2 reduced glucose levels reserved for intracellular utilization,particularly for the production of citrate,and thus increased theα-ketoglutarate/citrate ratio to promote the generation of glutamine-derived acetylcoenzyme A through the reductive pathway.Furthermore,reductive glutamine metabolism facilitated cell proliferation under hypoxia conditions,which supports in vivo tumor growth.In addition,PKM-deletion induced a reverse Warburg effect in tumorassociated stromal cells.Conclusions:PKM2 plays a critical role in promoting reductive glutamine metabolism and maintaining proton homeostasis.This study is helpful to increase the understanding of the physiological role of PKM2 in cancer cells.