益心泰颗粒对慢性心衰(心气虚兼血瘀水停证)大鼠AMPK、PGC-1α的影响

目的观察益心泰颗粒对慢性心力衰竭(CHF)(心气虚兼血瘀水停证)大鼠AMPK、PGC-1α的影响。方法采用丙硫氧嘧啶灌胃及阿霉素腹腔注射复制CHF(心气虚兼血瘀水停证)模型大鼠,将造模成功大鼠分为模型组与益心泰低、中、高剂量组和曲美他嗪组;另设正常对照组。灌胃4周后观察心肌组织病理结构,检测LVEF、血清NT-proBNP及心肌组织FFA、ATP/AMP、LAC、pAMPK、AMPK、PGC-1α水平。结果与模型组比较,益心泰颗粒低、中、高剂量组及曲美他嗪组LVEF、心肌组织ATP/AMP值、心肌组织p-AMPK、AMPK、PGC-1α相对灰度值均明显升高(P<0.05或P<0.01),血清NT-proBNP及心肌组织FFA、LAC明显降低(P<0.05或P<0.01)。结论益心泰颗粒能促进慢性心力衰竭(心气虚兼血瘀水停证)大鼠AMPK、PGC-1α表达,改善心肌能量代谢。

从失范到规范:网络直播打赏行为的法律性质认定——以我国近三年司法判例为样本

网络直播行业蓬勃发展,打赏模式不但满足了互动双方情感需要,亦切合主播和平台的实质利益。作为直播平台与主播的重要收入来源和盈利模式,直播打赏在创造巨大效益的同时相关纠纷亦与日俱增,司法实践中“同案不同判”现象频发。通过分析我国近三年的典型司法判例可以发现,法院在性质认定中的分歧在于,打赏关系是否存在对价及何种对价,充值打赏应否合并评价等问题,究其根源是因为法院对于直播打赏的法律关系认定上存在差异。基于此,通过剖析平台、主播及用户在打赏中的关系及定位,认定打赏本质上是基于用户和平台之间网络服务合同的消费行为,用户使用虚拟代币兑换并打赏主播,实际上是对虚拟货币的处分行为,不构建新的法律关系。

微生物菌剂与氮肥配施对紫花苜蓿生长及土壤性质的影响

为获得河西地区紫花苜蓿(Medicago sativa L.)人工草地上的最佳施肥组合。以‘惊盛’紫花苜蓿品种为试验材料,研究微生物菌剂与氮肥减量配施对紫花苜蓿植株生长、营养品质及土壤理化性质的影响,结果表明:与全量氮肥(CK)相比,微生物菌剂与氮肥减量处理的紫花苜蓿株高、干草产量无显著差异;与CK相比,C8,G8,C7和G7处理的紫花苜蓿粗蛋白、粗脂肪、中性和酸性洗涤纤维含量无显著差异,其中G7处理的紫花苜蓿粗蛋白含量最高;微生物菌剂与氮肥减量处理增加了土壤铵态氮含量(P<0.05),而土壤有机质、速效磷、含水率和pH值差异不显著;与CK相比,G7处理显著增加了土壤碱性磷酸酶活性(P<0.05)。通过对不同施肥处理的紫花苜蓿生长、营养和土壤指标的综合分析,综合表现最好的为G7(根瘤菌剂与氮肥减量30%),有利于减少河西地区氮肥用量,为河西地区紫花苜蓿的科学施肥提供依据。

转录因子Afndt6对黄曲霉毒力和侵染力的影响

为探究转录因子Afndt6对黄曲霉生长发育、毒素生物合成及侵染粮食籽粒能力的影响,通过同源重组构建Afndt6基因缺失的黄曲霉菌株,采用体视显微镜和切片观察手段研究Afndt6基因缺失对黄曲霉生长发育和孢子产生的影响,采用薄层色谱层析测定黄曲霉毒素生物合成量,以花生和玉米籽粒为基质评价基因缺失菌株的侵染力。结果表明:与对照菌株相比,ΔAfndt6菌株的生长速度、分生孢子的产量没有显著变化,但菌落分生孢子颜色变为白色;基因缺失菌株对细胞壁胁迫试剂刚果红和氧化胁迫压力不敏感,200μg/mL刚果红处理后对照菌株和ΔAfndt6菌株的生长抑制率分别为31.10%和25.81%,15 mmol/L H_(2)O_(2)处理后对照菌株和ΔAfndt6菌株的生长抑制率分别为47.94%和17.05%;ΔAfndt6菌株的黄曲霉毒素产量显著升高,对花生、玉米种子的侵染能力增强。Afndt6基因编码的转录因子能够影响黄曲霉生长发育,负调控黄曲霉毒素的生物合成,可为储粮过程中防控黄曲霉及黄曲霉毒素污染提供参考。

2023美国心脏协会癌症治疗相关高血压科学声明解读

2023年1月,美国心脏协会(AHA)发布癌症治疗相关高血压科学声明,对其发病机制和临床管理进行综述。现代抗癌治疗多以心血管毒性为代价,其中高血压是最常见的副作用之一,尤其是血管内皮生长因子抑制剂、酪氨酸激酶抑制剂和蛋白酶体抑制剂。癌症治疗相关高血压通常是剂量限制性,并且在中断或停止治疗后通常是可逆的。高血压的确切分子机制尚不清楚,近期研究表明,一氧化氮减少、内皮素-1增加、氧化应激、内皮功能障碍、交感神经外流增加和微血管稀疏具有重要作用。结合国际心脏肿瘤学会(IC-OS)的建议,该文对癌症治疗相关高血压的诊断及管理进行解读,目前尚无针对癌症治疗相关高血压患者的降压药物循证证据,故遵循普通人群高血压指南,并且需要多学科合作优化管理,以确保癌症治疗的最佳治疗效果,同时最大限度地减少心血管毒性。

基于CiteSpace量化分析的中国农户行为研究回溯与展望

农户行为是研究农业发展,制定农业政策的基本出发点。以CSSCI来源期刊上发表的农户行为相关文献作为样本,文章运用CiteSpace可视化文献分析软件,对国内农户行为研究的基本情况、研究热点和演进趋向进行了深入挖掘与梳理。结果表明,农户行为相关文献的数量整体呈上升趋势,并且具有明显的阶段特征;农户行为研究领域初步形成了核心作者群体、核心机构及核心刊物,但在研究规模、团队间合作、对问题的持续关注度等方面有待强化;对农户行为的研究可分为主流、潜力、新兴、边缘四大领域;当前对农户行为的影响因素、亲环境行为、金融行为、土地流转行为的研究成果最为丰富;在研究趋势上,对农户的环境规制行为、行为意愿的研究热度最高。后续研究应重点关注农户生产行为及其带来的农业发展方式的转变。

Active MoS_(2)-based electrode for green ammonia synthesis

Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology is to discover the catalysts with high selectivity and efficiency.In this work,the N_(2)-to-NH_(3)conversion on the functional MoS_(2)is fully investigated by density functional theory calculations since the layered MoS_(2)provides the ideal platform for the elaborating copies of the nitrogenase found in nature,wherein the functionalization is achieved via basal-adsorption,basal-substitution or edge-substitution of transition metal elements.Our results reveal that the edge-functionalization is a feasible strategy for the activity promotion;however,the basal-adsorption and basal-substitution separately suffer from the electrochemical instability and the NRR inefficiency.Specifically,MoS_(2)functionalized via edge W-substitution exhibits an exceptional activity.The energetically favored reaction pathway is through the distal pathway and a limiting potential is less than 0.20 V.Overall,this work escalates the rational design of the high-effective catalysts for nitrogen fixation and provides the explanation why the predicated catalyst have a good performance,paving the guidance for the experiments.

分布式光伏接入火电厂厂用系统的安全经济性分析

传统火电在当前能源结构转型的背景下将逐步转型为网源支撑和系统调节,与分布式光伏的厂用发电耦合是火电企业实现降本增效的一种有效尝试。但因厂用非统调电源的接入暂无相关规程指导,在系统安全稳定方面缺乏评估策略和实证参考。为此,以西北某火电厂的火电光伏互补供能系统为例,分析了其运行特点并给出了稳定性评价的技术框架,在不同机组、并网等级和最小光伏单元布置的实例中,讨论了静态潮流、暂态稳定和电能质量等应用评价问题,计算得到本例场站下火电机组厂用电减损效能实现了18%~42%的提升。该结论对火电厂应用“分布式光伏接入厂用系统”的发电技术模式有着典型的借鉴意义。

原发性膜性肾病预防性抗凝治疗研究进展

原发性膜性肾病血栓形成的风险较高,血栓形成通常发生在病程早期。血栓的形成与多种因素相关,目前普遍认为低蛋白血症为其独立风险因素,其他风险因素包括蛋白尿、M型磷脂酶A2受体抗体、D-二聚体等。虽然预防性抗凝被认为是原发性膜性肾病的一般支持治疗,但目前在时机选择、血清白蛋白阈值确定以及治疗方案制定等方面仍存在争议。该文对上述问题相关文献进行综述,以期为形成该类患者血栓防治标准提供参考,为临床实践提供参考。

胃癌并发静脉血栓栓塞症的抗凝研究进展

胃癌患者是发生静脉血栓栓塞(VTE)和出血的高危人群,并且发生VTE的患者常与不良结局有关,因此如何识别和管理胃癌患者的血栓风险成为临床上的难点。胃癌患者发生VTE的风险因素包括年龄、肥胖、外科手术、化学治疗等,识别高风险患者并积极采取预防策略十分必要。预防和治疗VTE的主要策略是使用抗凝药物。该文探讨胃癌患者预防与治疗VTE的指南和近期研究,以帮助临床医生为患者做出个体化决策,最大程度地改善患者的临床结局。

溶无机磷假单胞菌鉴定及对黑麦草生长的影响

【目的】研究假单胞菌属的溶解无机磷能力,以获得性状优良的菌株资源。【方法】将从植物根际分离的8株细菌接种于PKO培养基,采用钼锑钪比色法定量分析、分子生物学鉴定和半固体植物接种试验,探究了细菌溶无机磷能力和对黑麦草的促生作用,并对菌株进行初步鉴定。【结果】8株细菌在PKO液体培养基培养10 d后,溶解无机磷量在329.39~479.09μg/mL,其中菌株MPD4溶磷量最高;8株细菌均归属于假单胞菌属(Pseudomonas sp.)。【结论】与对照相比,8株细菌均可有效促进黑麦草的生长发育。

铁路隧道工程建造过程低碳评价系统研究

为提高铁路隧道建造过程低碳评价的效率,基于Matlab APP Designer交互式应用程序开发工具,采用MVC框架设计并研发了铁路隧道工程建造过程低碳评价系统。系统结构包括感知层、数据层、模型层、应用层和表现层,提供工程信息管理、评价指标筛选、指标权重计算、低碳综合评价等主题服务。以某铁路隧道工程为例对系统进行应用,结果表明:该隧道建造过程低碳等级为“较好”,与实际低碳施工管理情况相符合,基于系统提高了铁路隧道工程建造过程低碳评价效率。

基于BIM的装配式住宅建筑碳排放分析

以建筑全生命周期为出发点,研究了建筑节能水平和不同施工工艺对建筑碳排放量的影响。为探究分析建筑碳排放量以及相对于现浇混凝土结构建筑的单位面积减碳量,基于BIMBase平台,依据GB55015-2021《建筑节能与可再生能源利用通用规范》,选择上海市装配式住宅项目进行分析。结果如下:1)全生命周期年均碳排放指标达到35.73 kgCO_(2)e/m^(2),建材生产阶段碳排放占32.95%,建筑运行阶段碳排放占63.64%;空调系统年碳排放量指标达到9.21 kgCO_(2)/(m^(2)·a),其中制冷碳排放占比达到61.35%;建材回收可实现8.93%的减碳强度;2)建筑运行阶段碳排放强度较2016年执行的居建节能标准,降低10.17 kgCO_(2)e/m^(2),降低比例为46.03%;3)本项目采用预制率30%的PC结构,建造阶段碳排放较现浇混凝土结构降低比例为6.5%。

天门冬种子萌发响应干旱胁迫的生理机制研究

为解析干旱胁迫对天门冬种子萌发的影响,以天门冬种子为试验材料,观察了干旱胁迫下天门冬种子萌发的生理特性,用含不同PEG-6000浓度(0、3%、6%、9%、12%)的霍格兰德营养液处理天门冬种子,观察天门冬萌发种子的生理指标变化。结果表明,与对照相比,天门冬种子萌发率随PEG-6000浓度升高呈逐渐下降趋势,含水量随处理浓度升高呈下降趋势;MDA含量、电导率、过氧化氢、超氧阴离子和脯氨酸含量及超氧化物歧化酶活性随着处理浓度的增加呈升高趋势;在PEG-6000浓度低于9%时,天门冬萌发种子总可溶性糖含量和其他抗氧化酶活性均随处理浓度的增加而升高,在PEG-6000浓度高于9%时以上指标则下降。表明干旱胁迫能抑制天门冬种子的萌发,在较低程度的干旱胁迫时,种子细胞通过合成脯氨酸和可溶性糖调节渗透平衡,并通过抗氧化酶清除过多的活性氧,但是当细胞受到较高程度的干旱胁迫时大部分抗氧化酶活性受到抑制。

媒体融合发展论的三重维度刍议

媒体融合发展是一项系统工程。从政治逻辑来看,其既是发挥意识形态功能的战略部署,也是提升社会凝聚力的紧迫任务;从技术逻辑来看,传媒管理与新闻制作流程的体制机制改革刻不容缓,融合型新闻产品才能“飞入寻常百姓家”;从市场逻辑来看,融合发展以市场为资源配置手段,以市场检验媒体融合发展成效。

Research advances in enhanced coal seam gas extraction by controllable shock wave fracturing

With the continuous increase of mining in depth,the gas extraction faces the challenges of low permeability,great ground stress,high temperature and large gas pressure in coal seam.The controllable shock wave(CSW),as a new method for enhancing permeability of coal seam to improve gas extraction,features in the advantages of high efficiency,eco-friendly,and low cost.In order to better utilize the CSW into gas extraction in coal mine,the mechanism and feasibility of CSW enhanced extraction need to be studied.In this paper,the basic principles,the experimental tests,the mathematical models,and the on-site tests of CSW fracturing coal seams are reviewed,thereby its future research directions are provided.Based on the different media between electrodes,the CSW can be divided into three categories:hydraulic effect,wire explosion and excitation of energetic materials by detonating wire.During the process of propagation and attenuation of the high-energy shock wave in coal,the shock wave and bubble pulsation work together to produce an enhanced permeability effect on the coal seam.The stronger the strength of the CSW is,the more cracks created in the coal is,and the greater the length,width and area of the cracks being.The repeated shock on the coal seam is conducive to the formation of complex network fracture system as well as the reduction of coal seam strength,but excessive shock frequency will also damage the coal structure,resulting in the limited effect of the enhanced gas extraction.Under the influence of ground stress,the crack propagation in coal seam will be restrained.The difference of horizontal principal stress has a significant impact on the shape,propagation direction and connectivity of the CSW induced cracks.The permeability enhancement effect of CSW is affected by the breakage degree of coal seam.The shock wave is absorbed by the broken coal,which may hinder the propagation of CSW,resulting in a poor effect of permeability enhancement.When arranging two adjacent boreholes for CSW permeability enhancement test,the spacing of boreholes should not be too close,which may lead to negative pressure mutual pulling in the early stage of drainage.At present,the accurate method for effectively predicting the CSW permeability enhanced range should be further investigated.

Extended finite element-based cohesive zone method for modeling simultaneous hydraulic fracture height growth in layered reservoirs

In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hydraulic fractures in layered porous reservoirs with modulus contrast.The coupled hydromechanical model is first verified against an analytical solution and a laboratory experiment.Then,the fracture geometry(e.g.height,aperture,and area)and fluid pressure evolutions of multiple hydraulic fractures placed in a porous reservoir interbedded with alternating stiff and soft layers are investigated using the model.The stress and pore pressure distributions within the layered reservoir during fluid injection are also presented.The simulation results reveal that stress umbrellas are easily to form among multiple hydraulic fractures’tips when propagating in soft layers,which impedes the simultaneous height growth.It is also observed that the impediment effect of soft layer is much more significant in the fractures suppressed by the preferential growth of adjoining fractures.After that,the combined effect of in situ stress ratio and fracturing spacing on the multi-fracture height growth is presented,and the results elucidate the influence of in situ stress ratio on the height growth behavior depending on the fracture spacing.Finally,it is found that the inclusion of soft layers changes the aperture distribution of outmost and interior hydraulic fractures.The results obtained from this study may provide some insights on the understanding of hydraulic fracture height containment observed in filed.

Coseismic Coulomb stress changes induced by a 2020-2021 M_(W)>7.0 Alaska earthquake sequence in and around the Shumagin gap and its influence on the Alaska-Aleutian subduction interface

Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6 Sand Point strike-slip earthquake on October 19,2020,and the M_(W)8.2 Chignik thrust earthquake on July 29,2021.The spatial and temporal proximity of these three earthquakes prompts us to probe stress-triggering effects among them.Here we examine the coseismic Coulomb stress change imparted by the three earthquakes and their influence on the subduction interface.Our results show that:(1)The Simeonof earthquake has strong loading effects on the subsequent Sand Point and Chignik earthquakes,with the Coulomb stress changes of 3.95 bars and 2.89 bars,respectively.The Coulomb stress change caused by the Sand Point earthquake at the hypocenter of the Chignik earthquake is merely around 0.01 bars,suggesting the negligible triggering effect on the latter earthquake;(2)The triggering effects of the Simeonof,Sand Point,and Chignik earthquakes on aftershocks within three months are not well pronounced because of the triggering rates of 38%,14%,and 43%respectively.Other factors may have played an important role in promoting the occurrence of these aftershocks,such as the roughness of the subduction interface,the complicated velocity structure of the lithosphere,and the heterogeneous prestress therein;(3)The three earthquakes caused remarkable coseismic Coulomb stress changes at the subduction interface nearby these mainshocks,with an average Coulomb stress change of 3.2 bars in the shallow region directly inwards the trench.

Westerlies Affecting the Seasonal Variation of Water Vapor Transport over the Tibetan Plateau Induced by Tropical Cyclones in the Bay of Bengal

This study investigates the activity of tropical cyclones(TCs)in the Bay of Bengal(BOB)from 1979 to 2018 to discover the mechanism affecting the contribution rate to the meridional moisture budget anomaly(MMBA)over the southern boundary of the Tibetan Plateau(SBTP).May and October–December are the bimodal phases of BOB TC frequency,which decreases month by month from October to December and is relatively low in May.However,the contribution rate to the MMBA is the highest in May.The seasonal variation in the meridional position of the westerlies is the key factor affecting the contribution rate.The relatively southern(northern)position of the westerlies in November and December(May)results in a lower(higher)contribution rate to the MMBA.This mechanism is confirmed by the momentum equation.When water vapor enters the westerlies near the trough line,the resultant meridional acceleration is directed north.It follows that the farther north the trough is,and the farther north the water vapor can be transported.When water vapor enters the westerlies from the area near the ridge line,for Type-T(Type-R)TCs,water vapor enters the westerlies downstream of the trough(ridge).Consequently,the direction of the resultant meridional acceleration is directed south and the resultant zonal acceleration is directed east(west),which is not conducive to the northward transport of water vapor.This is especially the case if the trough or ridge is relatively south,as the water vapor may not cross the SBTP.

考虑需求响应的交直流混合配电网分布式光伏承载能力鲁棒评估方法

鲁棒优化通常采用多面体模型来描述分布式光伏出力的不确定性,却忽略了分布式光伏出力的时空相关性,为此,该文建立了分布式光伏的时空相关性多面体模型,提出了考虑需求侧响应的交直流混合配电网分布式光伏承载能力鲁棒评估方法。首先,建立分布式光伏出力不确定性的时空相关性多面体模型和电价激励型需求侧响应模型,以最大化分布式光伏并网容量为目标,考虑交直流混合配电网中多种运行约束和调节策略,建立交直流混合配电网分布式光伏承载能力两阶段鲁棒评估模型,并采用列与约束生成算法进行迭代求解。在70节点系统上验证了算法的有效性,仿真结果表明:不同的管理策略有助于提升交直流混合配电网的分布式光伏承载能力。