Granular behaviour under bi-directional shear with constant vertical stress and constant volume

This paper aims to investigate the role of bi-directional shear in the mechanical behaviour of granular materials and macro-micro relations by conducting experiments and discrete element method(DEM)modelling.The bi-directional shear consists of a static shear consolidation and subsequent shear under constant vertical stress and constant volume conditions.A side wall node loading method is used to exert bi-directional shear of various angles.The results show that bi-directional shear can significantly influence the mechanical behaviour of granular materials.However,the relationship between bidirectional shear and mechanical responses relies on loading conditions,i.e.constant vertical stress or constant volume conditions.The stress states induced by static shear consolidation are affected by loading angles,which are enlarged by subsequent shear,consistent with the relationship between bidirectional shear and principal stresses.It provides evidence for the dissipation of stresses accompanying static liquefaction of granular materials.The presence of bi-directional principal stress rotation(PSR)is demonstrated,which evidences why the bi-directional shear of loading angles with components in two directions results in faster dissipations of stresses with static liquefaction.Contant volume shearing leads to cross-anisotropic stress and fabric at micro-contacts,but constant vertical stress shearing leads to complete anisotropic stress and fabric at micro-contacts.It explains the differentiating relationship between stress-strain responses and fabric anisotropy under these two conditions.Micromechanical signatures such as the slip state of micro-contacts and coordination number are also examined,providing further insights into understanding granular behaviour under bi-directional shear.

基于地形特征的无人机遥感梯田影像边缘提取方法

梯田具有蓄水固沙的作用,是旱作农业区重点建设的高产稳产农田设施,为粮食增产、农民增收提供了有力保障。因仅基于影像数据采用边缘提取方法进行梯田区域分割效果不理想,及时准确地掌握梯田信息较为困难。无人机遥感技术的不断发展为高精度梯田地形信息的获取提供了新方法。本研究以甘肃省榆中县为例,首先从数字高程模型DEM数据中提取坡度,将正射影像与坡度数据融合,并通过基于Canny算子的粗边缘提取方法和基于多尺度分割的精细边缘提取方法,对比分析坡度对无人机遥感梯田影像边缘提取的影响。试验结果表明,正射影像和坡度融合的提取效果均优于单一的正射影像数据提取效果,粗边缘提取方法中正射影像和坡度融合的数据源精度平均提高了23.97%,精细边缘提取方法中正射影像和坡度融合的数据源精度平均提高了17.84%。研究表明,在无人机遥感梯田影像边缘提取中加入一定的地形特征,可以取得更好的边缘提取效果。

Fucoidan antagonizes diet-induced obesity and inflammation in mice

Obesity is an escalating global pandemic posing a serious threat to human health.The intervention therapy using weight-reducing drugs,accompanied by lifestyle modification,is a strategy for the treatment of obesity.In the present study,we explored the role of fucoidan,a seaweed compound,on high-fat diet(HFD)-induced obesity in mice.We found that fucoidan treatment significantly reduced the body fat and caused redistribution of visceral and subcutaneous fat in HFD-fed mice.Meanwhile,fucoidan treatment inhibited adipocyte hypertrophy and inflammation in adipose tissue.Collectively,these results suggest that fucoidan may be a promising treatment for obesity and obesity-induced complications.

Seismogenic tectonics of the Qian-Gorlos earthquake in Jilin Province,China

The Qian-Gorlos earthquake, which occurred in the Songliao basin in Jilin Province in 1119 AD, was the largest earthquake to occur in NE China before the 1975 Haicheng earthquake. Based on historical records and surface geological investigations, it has been suggested previously that the earthquake epicenter was in the Longkeng area. However, other workers have considered the epicenter to be in the Halamaodu area based on the landslides and faults found in this region. No seismogenic structure has yet been found in either of these two regions.We tried to detect active faults in the urban areas of Songyuan City, where the historical earthquake was probably located. One of the aims of this work was to clarify the seismogenic structure so that the seismic risk in the city could be more accurately evaluated. The area was investigated and analyzed using information from remote sensing and topographic surveys, seismic data from petroleum exploration, shallow seismic profiles, exploratory geological trenches on fault outcrops, and borehole data. The geophysical data did not reveal any evidence of faults cutting through Cretaceous or later strata under the Longkeng scarp, which has been suggested to be structural evidence of the Qian-Gorlos earthquake. The continuous fault surfaces on the back edge of terraces in theHalamaodu area stretch for [3.5 km and were probably formed by tectonic activity. However, results from shallow seismic profiles showed that the faults did not extend downward, with the corresponding deep structure being identified as a gentle kink band. A new reverse fault was found to the west of the two suggested epicenters, which presented as a curvilinear fault extending to the west, and was formed by two groups of NE- and NW-trending faults intersecting the Gudian fault. Three-dimensional seismic and shallow seismic data from petroleum exploration revealed its distinct spatial distribution and showed that the fault may cut through Late Quaternary strata. Exploration boreholes and later geomorphological studies provided further proof of this. Based on these results and analysis,the Gudian fault was confirmed as having been an active fault since the Late Quaternary, with the possibility of earthquakes of magnitude [7 in the future. The QianGorlos earthquake was most probably the result of breakage on one or two sections of this 66-km-long fault.

基于铜死亡相关基因构建肺腺癌预后模型和药物敏感性分析

背景与目的肺癌是全球最常见的恶性肿瘤之一,目前肺癌筛查和治疗策略不断完善,但其5年生存率仍然很低,严重危害人类的健康。因此探索新的生物标志物,提供个体化治疗并改善患者预后至关重要。铜死亡是一种新发现的细胞死亡类型,是由于细胞内过量铜离子积累,最终导致细胞死亡,已有研究提示其与肺腺癌(lung adenocarcinoma,LUAD)的发生发展密切相关。本研究基于肿瘤基因组图谱(The Cancer Genome Atlas,TCGA)数据库,探究铜死亡相关基因(cuproptosis related gene,CRGs)与LUAD预后之间的关联,建立预后风险模型并分析CRGs与LUAD免疫细胞浸润之间的相互作用,为肺腺癌患者的治疗及预后提供参考。方法从TCGA数据库中下载LUAD组织和癌旁或正常肺组织的RNA-seq数据,从基因型-组织表达资料库(Genotype-tissue Expression,GTEx)下载正常肺组织的RNA-seq数据,并从基因表达综合数据库(Gene Expression Omnibus,GEO)下载462例肺腺癌数据作为验证,采用单因素Cox和Lasso-Cox回归分析构建评估预后的风险评分模型,用受试者工作特征(receiver operating characteristic,ROC)曲线及校准曲线评价模型的预测能力。并进一步对高、低风险组进行免疫相关和药物敏感性分析。结果共得到1656个CRGs,其中有1356个存在差异表达的CRGs,基于单因素Cox和Lasso-Cox回归分析筛选出13个CRGs构建预后风险模型,ROC曲线1、3、5年的曲线下面积(area under the curve,AUC)分别为0.749、0.740、0.689。进一步研究高、低风险组之间免疫相关功能和免疫检查点差异分析。高风险组对萨沃替尼、帕博西尼、阿糖胞苷等药物敏感性更高,更容易从免疫治疗中获益。结论基于13个CRGs构建的风险模型具有较好的预后价值,可以辅助LUAD患者进行个体化治疗,为LUAD的治疗及预后研究提供了重要理论依据。

Effects of Rainfall Change on Agricultural Non-point Source Pollution in Liangping County

[Objective] The study aimed to discuss the impact of rainfall change on agricultural non-point source pollution in Uangping County. E Method ] Based on daily precipitation data of Liangping from 1955 to 2011, changes of precipitation and frequency of heavy rain in Uangping during a year were analyzed firstly, and then the risk of surface runoff caused by rainfall to agricultural non-point source pollution was studied, finally chan- ging trends of annual average precipitation and frequency during 1955 -2011 were discussed using Mann-Kendal method. [ Result] Total precipitati- on of heavy rain in Liangping mainly concentrated from late May to early September, especially in eady and middle July as well as early September. Meanwhile, fertilizer and pesticide were applied to main crops in Liangping in the periods above, so agricultural non-point source pollution became more serious. In recent 57 years, annual average precipitation and frequency of heavy rain in Liangping showed an increasing trend respectively, and surface runoff rose with the increase of the precipitation, thereby probably enlarging agricultural pollution area. [ Conclusion] The research could provide a theoretical basis and technical support for the control of agricultural non-point source pollution.

Winter Wheat Drought Monitoring and Comprehensive Risk Assessment： Case Study of Xingtai Administrative District in North China

Drought monitoring is the base for drought coping and adaptation. Xingtai is located in North China＇s key winter wheat production areas where drought is severe and frequent. The rainfall during winter wheat growing season is just about 1/3 of total demand. Xingtai has typical mountainous, hilly and plain agricultural zones, compound rain-fed and irrigated farming patterns. The winter wheat irrigation has heavily depended on overdraw of groundwater in recent decades. In the study, the MODIS （Moderate-Resolution Imaging Spectroradiometer） images taken at the key winter wheat growing season （Mar. to May） in normal rainfall year （2006） were selected, extracted NDVI （Normalized Difference Vegetation Index） and LST （Land Surface Temperature） data, calculated TVDI （Temperature and Vegetation Drought Index）, classified and mapped winter wheat drought intensity. Further, based on TVDI, a CDRA （Comprehensive Drought Risk Assessment） model for winter wheat drought disaster risk assessment was constructed and zoning was made. Verified by winter wheat yield, the risk zoning by CDRA is consistent with actual crop failure space. This method can be used in drought risk management.

Evaluation of the Agricultural Non-point Source Pollution in Chongqing Based on PSR Model

Through a series of exploration based on PSR framework model,for the purpose of building a suitable Chongqing agricultural nonpoint source pollution evaluation index system model framework,combined with the presence of Chongqing specific agro-environmental issues,we build a agricultural non-point source pollution assessment index system,and then study the agricultural system pressure,agro-environmental status and human response in total 3 major categories,develope an agricultural non-point source pollution evaluation index consisting of 3 criteria indicators and 19 indicators. As can be seen from the analysis,pressures and responses tend to increase and decrease linearly,state and complex have large fluctuations,and their fluctuations are similar mainly due to the elimination of pressures and impact,increasing the impact for agricultural non-point source pollution.

A multi-center study on genetic variations in the fusion protein of respiratory syncytial virus from children with Acute Lower Respiratory Tract Infections in China during 2017-2021

Respiratory syncytial virus(RSV)is a significant cause of acute lower respiratory tract infection(ALRTI)in children underfive years of age.Between 2017 and 2021,396 complete sequences of the RSV F gene were obtained from 500 RSV-positive throat swabs collected from ten hospitals across nine provinces in China.In addition,151 sequences from China were sourced from GenBank and GISAID,making a total of 549 RSV F gene sequences subjected to analysis.Phylogenetic and genetic diversity analyses revealed that the RSV F genes circulating in China from 2017 to 2021 have remained relatively conserved,although some amino acids(AAs)have undergone changes.AA mutations with frequencies10%were identified at six sites and the p27 region:V384I(site I),N276S(site II),R213S(siteØ),and K124N(p27)for RSV A;F45L(site I),M152I/L172Q/S173 L/I185V/K191R(site V),and R202Q/I206M/Q209R(siteØ)for RSV B.Comparing mutational frequencies in RSV-F before and after 2020 revealed minor changes for RSV A,while the K191R,I206M,and Q209R frequencies increased by over 10%in RSV B.Notably,the nirsevimab-resistant mutation,S211N in RSV B,increased in frequency from 0%to 1.15%.Both representative strains aligned with the predicted RSV-F structures of their respective prototypes exhibited similar conformations,with low root-mean-square deviation values.These results could provide foundational data from China for the development of RSV mAbs and vaccines.

Macrophage scavenger receptor A1 promotes skeletal muscle regeneration after hindlimb ischemia

The macrophage-mediated inflammatory response is crucial for the recovery of skeletal muscle following ischemia.Therefore,macrophage-based therapeutic targets need to be explored for ischemic disease.In the current study,we found that the mRNA levels of scavenger receptor A1(Sr-a1)were elevated in patients with critical limb ischemia,based on an analysis of the Gene Expression Omnibus data.We then investigated the role and underlying mechanisms of macrophage SR-A1 in a mouse hindlimb ischemia(HLI)model.Compared with the Sr-a1^(fl/fl)mice,the Lyz^(Cre+)/Sr-a1^(flox/flox)(Sr-a1~(ΔMΦ))mice showed significantly reduced laser Doppler blood flow in the ischemic limb on day seven after HLI.Consistently,histological analysis revealed that the ischemic limb of the Sr-a1~(ΔMΦ)mice exhibited more severe and prolonged necrotic morphology,inflammation,fibrosis,decreased vessel density,and delayed regeneration than that of the control Sr-a1~(fl/fl)mice.Furthermore,restoring wild-type myeloid cells to the Sr-a1 knockout mice effectively improved the Doppler perfusion in the ischemic limb and mitigated skeletal muscle damage seven days after HLI.Consistent with these in vivo findings,co-cultivating macrophages with the mouse myoblast cell line C2C12 revealed that the Sr-a1^(-/-)bone marrow macrophages significantly inhibited myoblast differentiation in vitro.Mechanistically,SR-A1 enhanced the skeletal muscle regeneration in response to HLI by inhibiting oncostatin M production via suppression of the NF-κB signaling activation.These findings indicate that SR-A1 may be a promising candidate protein to improve tissue repair and regeneration in peripheral ischemic arterial disease.

儿童先天性脊柱畸形患者围手术期加速康复管理方案的效果评价

目的探讨加速康复外科(ERAS)在儿童先天性脊柱畸形患者围手术期的治疗效果,总结临床经验。方法将2020年5月至2021年1月北京儿童医院收治的59例儿童先天性脊柱畸形患者纳入研究,所有患者均接受脊柱后路截骨矫形植骨融合内固定术。其中男22例,女37例,年龄(7.4±4.1)岁。根据管理模式将患者分为ERAS组(29例)和对照组(30例)。ERAS组患者围手术期采用加速康复管理模式,主要包括:高蛋白饮食、缩短禁食水时间、优化麻醉方案、多模式镇痛等。对照组患者采用传统围手术期管理模式。对比两组患者手术、饮食、疼痛评分、化验检查等指标。结果所有患者均顺利完成手术。术后3 d内ERAS组患者体温及疼痛评分均低于对照组(P<0.05)。ERAS组患者术后排气、排便时间为(1.0±0.8)d和(2.5±0.9)d,均明显早于对照组的(3.4±0.8)d和(4.0±1.1)d,差异均有统计学意义(均P<0.05)。术后第3天ERAS组患者C-反应蛋白为38(8,46)mg/L,明显低于对照组的47(22,93)mg/L,差异有统计学意义(P=0.023)。术后第3天血红蛋白水平ERAS组为(110.7±9.6)g/L,明显高于对照组的(104.5±11.4)g/L,差异有统计学意义(P=0.029)。术后ERAS组和对照组分别有8例(27.6%)和9例(30.0%)患者出现并发症(P=1.000),两组均以轻度腹痛、腹胀最为常见,多数未予特殊处理。结论ERAS是儿童先天性脊柱畸形患者围手术期安全有效的管理模式,与传统模式相比可显著提高治疗效率,值得临床推广应用。

The Hybrid Bidirectional DC/DC Converter:Mutual Control and Stability Analysis

A hybrid bidirectional DC/DC converter(BDC)is proposed as the fundamental DC/DC module in solid-state transformers,which combines a bidirectional LLC converter and a dual-active-bridge(DAB)converter.Integrated with a mutual control scheme,both parts of this hybrid BDC can be unified into an interdependent community.In this hybrid BDC,the LLC converter supports the output voltage and improves stability by working at the resonant frequency mode and the DAB converter enhances the BDC power capability by controlling the LLC output current constant.The BDC can achieve the full-load-range soft switching of all active switches by designing the auxiliary inductor of LLC and the minimum output current of DAB.By comparing to the single DAB,the proposed BDC has the higher phase and gain margin which means the BDC improved the relative stability based on Nyquist criterion.To solve the bidirectional power control problem,a dead-band voltage control logic is adopted which can determine the BDC’s power direction based on the output voltage change.A 200 V experimental system has verified the aforementioned features and functions of the BDC.

Mechanically and operationally stable flexible inverted perovskite solar cells with 20.32%efficiency by a simple oligomer cross-linking method

Due to their great potential in wearable and portable electronics,flexible perovskite solar cells(FPSCs)have been extensively studied.The major challenges in the practical applications of FPSCs are efficiency,operational stability,and mechanical stability.Herein,we developed a facile approach by incorporating a cross-linking oligomer of trimethylolpropane ethoxylate triacrylate(TET)into perovskite films to simultaneously enhance the power conversion efficiency(PCE)and stability of FPSCs.A PCE of 20.32%was achieved,which are among the best results for the inverted FPSCs.Both mechanical and environmental stabilities were improved for the TET-incorporated FPSCs.In particular,the PCE retained approximately87%of its initial value after 20,000 bending cycles at a radius of 4 mm.The inverted FPSCs retained 85%of the initial PCE after 500 h storage at 85°C and 90%after 900 h continuous one-sun illumination.A joint experiment–theory analysis ascribed the underlying mechanism to the reduced defect densities,improved crystallinity,and stability of the perovskite absorbers on flexible substrates caused by TET incorporation.

Invasive sphenoid sinus aspergillosis mimicking sellar tumor: a report of 4 cases and systematic literature review

Background:Invasive sphenoid sinus aspergillosis is a rare but life-threatening condition usually found in immunocompromised patients.When involving cavernous sinus and surrounding structures,patients are frequently misdiagnosed with a neoplasm or sellar abscess.Timely diagnosis and intervention are crucial to patients’outcomes.The objective of this study is to review cases of invasive sphenoid sinus aspergillosis to describe disease manifestations,imaging features,treatment,and outcome.Case presentation:We describe four patients with invasive sphenoid sinus aspergillosis misdiagnosed as sellar tumors preoperatively.The mass was completely removed in three patients and partially removed in one patient microscopically.Pathological examinations confirmed Aspergillus in all cases.All four patients received anti-fungal agents postoperatively.There was no recurrence at the time of each patient’s follow-up date.One patient with complete resection was lost to follow-up while the other three patients’neurologic function improved.Additionally,we performed a systematic review regarding invasive sphenoid sinus aspergillosis of existing English literature.Conclusion:With regard to clinical symptoms,headache,vision impairment,and ophthalmoplegia were observed in over half of the patients in the literature.A sellar mass with bone destruction on CT and involvement of cavernous sinus is highly suggestive of invasive fungal sphenoid sinusitis.Immediate surgical removal of the lesion is recommended for invasive sphenoid sinus aspergillosis to preserve nerve function and increase the likelihood of survival.

镍铬混合型氧化矿硫酸铵焙烧物料的溶出及溶出动力学

镍是国防、航空航天、能源、交通运输、石油化工等领域不可缺少的资源,也是我国最重要的战略有色金属之一。随着镍需求增加,硫化镍矿资源迅速减少,趋于枯竭。氧化镍矿资源丰富、开采成本低,其作为镍冶炼资源的开发利用日趋受到关注。为了更好地利用含铬氧化镍矿,有必要开展镍铬混合型氧化矿中有价组元提取分离的研究。本工作考察了溶出液固比、溶出温度、溶出时间、搅拌速率对镍、铁、镁溶出率的影响,确定了合适的水溶出工艺条件。考察了硫酸铵焙烧镍铬混合型氧化矿的焙烧物料中镍、铁、镁溶出过程的动力学。采用硫酸铵焙烧镍铬混合型氧化矿,在铵矿配比1.7:1、焙烧温度748 K、焙烧时间2 h条件下得到焙烧物料,以焙烧物料为研究对象,考察了各因素对焙烧物料中镍、铁、镁溶出效率的影响。适宜的溶出条件为:溶出温度353 K、溶出时间60 min、液固质量比5:1、搅拌速率500 r/min。在此条件下,镍、铁、镁的溶出率分别为94.3%,88.7%和84.9%。焙烧物料中镍、铁、镁的溶出均可分为0~15 min和15~40 min两个阶段,均受无固体产物层生成的外扩散控制。

The Palestine-Israel Issue in the Post-Covid-19 Era—From the Perspective of Neocolonialism

Strictly speaking,the economic relationship between Israel and Palestine cannot be simply defined as neocolonial occupation,but are closely related to neo-colonialism,in terms of control,dependence,resistance,exploitation,monopoly and interference.Therefore,neo-colonialism can be used as a perspective to analyse the economic relations between Palestine and Israel.Although the two sides have always been in a relatively hostile relationship,due to years of stalemate and Israeli economic control,the two sides have formed an interdependent economic relationship,where Israel has a relatively dominant position in the relations,thanks to its long-term occupation and control over the land,while the Palestinian economy will continue to remain highly dependent on Israel,despite its official efforts to achieve economic disengagement.In this case,Israel is reluctant to sever the relationship,and Palestine is unable to decouple from the Israeli economy.The outbreak of the Covid-19 pandemic has made the prospects for Palestinian-Israeli peace talks even bleaker.As the peace process continues to stall,a settlement to resolve the dispute between Israel and the Palestinians remains highly unlikely.

MLKL-mediated endothelial necroptosis drives vascular damage and mortality in systemic inflammatory response syndrome

The hypersecretion of cytokines triggers life-threatening systemic inflammatory response syndrome(SIRS),leading to multiple organ dysfunction syndrome(MODS)and mortality.Although both coagulopathy and necroptosis have been identified as important factors in the pathogenesis of SIRS,the specific cell types that undergo necroptosis and the interrelationships between coagulopathy and necroptosis remain unclear.In this study,we utilized visualization analysis via intravital microscopy to demonstrate that both anticoagulant heparin and nonanticoagulant heparin(NAH)pretreatment protect mice against TNF-α-induced mortality in SIRS.Moreover,the deletion of Mlkl or Ripk3 resulted in decreased coagulation and reduced mortality in TNF-α-induced SIRS.These findings suggest that necroptosis plays a key role upstream of coagulation in SIRS-related mortality.Furthermore,using a genetic lineage tracing mouse model(Tie2-Cre;Rosa26-tdT),we tracked endothelial cells(ECs)and verified that EC necroptosis is responsible for the vascular damage observed in TNF-α-treated mice.Importantly,Mlkl deletion in vascular ECs in mice had a similar protective effect against lethal SIRS by blocking EC necroptosis to protect the integrity of the endothelium.Collectively,our findings demonstrated that RIPK3–MLKL-dependent necroptosis disrupted vascular integrity,resulting in coagulopathy and multiorgan failure,eventually leading to mortality in SIRS patients.These results highlight the importance of targeting vascular EC necroptosis for the development of effective treatments for SIRS patients.