电-磁-机耦合视域下考虑气隙影响的变压器铁心振动特性精细化模拟方法

目前,对于铁心振动计算通常采用有限元仿真来实现,但该方法计算时间长且效率低,为解决此问题,该文提出了基于机-电类比的铁心多场耦合特性精细化建模与计算方法。根据铁心步进搭接区域的结构特点,对搭接区域铁心进行磁路建模,建立考虑气隙影响的铁心等效磁路模型。根据机-电类比方法和振动理论,建立可描述变压器铁心振动的集总式和分布式等效振动回路模型,基于搭接区域磁场分布特性建立二端口级联形式的等效振动回路模型,实现了铁心振动特性的快速精准计算。搭建了叠片铁心测试平台并进行实验,通过将测量结果与计算结果对比,发现励磁电流、铁心磁通密度、位移和加速度等具有较好的一致性,验证了所提方法的有效性和准确性。

冷凉区黑土有机质和玉米产量双提升技术探索及经济效益分析

为明确有机肥还田+保护性耕作措施下黑龙江省西部土壤有机质和作物产量的双提升技术效果,2021年10月,在黑龙江省西部齐齐哈尔市梅里斯区开展试验,以玉米为供试作物,设置5个处理:有机肥+深松40 cm(YS40)、秸秆留茬+深松40 cm(WS40)、有机肥+旋耕20 cm(YS20)、秸秆留茬+旋耕20 cm(WS20)、有机肥表施+免耕(YB);一个对照:秸秆留茬+免耕(CK)。结果表明:施入有机肥的处理能够提升深土层土壤肥力,在20~40 cm土层中YS20处理与CK处理相比有机质和全氮依次提升11.56 g·kg^(-1)和0.57 g·kg^(-1);40~60 cm土层中YS40处理与CK处理相比有机质和全氮依次提升2.83 g·kg^(-1)和0.28 g·kg^(-1)。土壤结构方面,在0~20 cm土层中YB处理的容重较CK降低17.5%、含水量提升35.5%,40~60 cm土层中YS40处理的容重较CK处理降低5.3%、含水量提升38.4%。有机肥与保护性耕作处理提高了玉米不同生育时期叶面积指数、叶绿素含量和干物质积累量,进而提高了玉米产量,第二年的YS40、YS20、YB处理较CK处理分别增产14.5%、18.5%、11.4%。收益分析表明,与CK处理相比,2021年YB处理和2022年YS20处理收益增加最多,分别增加5770元·hm^(-2)和5223元·hm^(-2)。综上所述,黑龙江省西部薄层黑土实施有机肥还田+保护性耕作是提升土壤有机质、有机碳储量、全氮、全氮储量、玉米产量和经济效益的有效措施。

197例胃结石内镜下治疗与保守治疗的比较分析

目的比较胃结石患者的不同治疗方法,为临床治疗提供数据支持。方法2013年7月至2024年1月就诊宁夏医科大学总医院、宁夏医科大学总医院心脑血管病医院经胃镜检查确诊为胃结石患者197例。统计患者的一般资料等数据,依据真实世界研究方法,按照患者自主选择的治疗方法进行分组;将研究对象分为4组,分别为药物保守治疗组、内镜下自制圈套器治疗组、一次性圈套器治疗组、碎石器治疗组。采用单因素方差分析对数据进行统计学分析。结果胃结石多发生于男性,年龄(55.45±14.21)岁,85.3%的患者有进食柿子病史,86.3%的患者合并溃疡,其中65.9%位于胃角。自制圈套器组治疗费用花费最低,碎石器组治疗费用最高;内镜下的三种治疗方式中临床症状缓解时间无差别,自制圈套器组的患者满意度最高,但药物保守治疗组临床症状缓解时间最长且患者满意度最低。颜色为黑绿色的胃结石其内镜治疗次数和内镜下治疗时间明显高于颜色为杂色和金黄色的胃结石。结论胃结石患者需综合考虑患者结石大小、颜色及患者本人的意愿,充分告知患者病情及不同治疗的优势。对于较大结石(约5 cm以上的胃结石)患者,选择内镜下自制圈套器治疗作为首选的治疗方法。

新疆荒漠绿洲区大麦田阔叶杂草化学防除药效评价

【目的】筛选对大麦田阔叶杂草具有较好防效的除草剂,为荒漠绿洲生态区安全高效应用除草剂提供依据。【方法】采用随机区组的方法,调查各药剂处理小区的杂草株数和地上部分鲜质量,评价供试药剂对大麦田阔叶杂草的防除效果及安全性。【结果】药后50 d,20%双氟·氟氯酯WG 19.50 g/hm^(2)、10%双唑草酮OD 37.50 g/hm^(2)、200 g/L氯氟吡氧乙酸EC 210.00 g/hm^(2)、22%氟吡·双唑酮OD 165.00 g/hm^(2)、50%2甲·氯·双氟SC 450.00 g/hm^(2)、87.5%2,4-滴异辛酯EC 577.50 g/hm^(2)、25%辛酰溴苯腈EC 562.50 g/hm^(2)和75%苯磺隆WG 22.50 g/hm^(2)对阔叶杂草灰绿藜和卷茎蓼的株防效和鲜质量防效较好,防效分别为90.87%~96.02%和94.15%~98.08%,各处理株防效和鲜质量防效之间均无显著性差异。【结论】20%双氟·氟氯酯WG、10%双唑草酮OD、200 g/L氯氟吡氧乙酸EC、22%氟吡·双唑酮OD、50%2甲·氯·双氟SC、87.5%2,4-滴异辛酯EC、25%辛酰溴苯腈EC和75%苯磺隆WG可防除大麦田灰绿藜、卷茎蓼等阔叶杂草,且对大麦生长安全,可在大田合理轮换使用。

不同档位脊神经后支低温等离子消融术治疗慢性关节突关节源性腰痛

目的:探讨不同档位的低温等离子消融术(low-temperature plasma radiofrequency ablation,LTPRA)治疗慢性关节突关节源性腰痛的临床疗效及安全性,为临床提供理论依据。方法:纳入2021年2月至2022年2月在中日友好医院疼痛科接受LTPRA治疗的92例慢性关节突关节源性腰痛住院病人,根据LTPRA治疗的档位分为1档组(平均功率13 W,术区温度40℃左右,51例)与3档组(平均功率49 W,术区温度60℃左右,41例)。分别对两组术前、术后第2周、1、3、6、12个月的疼痛数字分级评分法(numerical rating scale,NRS)评分、Oswestry功能障碍指数(Oswestry disability index,ODI)、非甾体抗炎药(nonsteroidal antiinflammatory drugs,NSAIDs)和/或阿片类药物的使用情况、手术相关并发症进行随访评估以及统计学分析。结果:与术前相比,术后2周、1、3、6、12个月两组NRS评分和ODI评分均明显下降;药物使用率显著下降。组间比较发现,术后1个月至12个月3档组NRS评分均低于1档组,术后2周以及术后6个月至术后12个月,3档组ODI评分均低于1档组,差异有统计学意义。3档组中更多比例病人出现术后短期轻度并发症,但差异无统计学意义。结论:针对慢性关节突关节源性腰痛,1档、3档治疗均有效,3档的治疗效果更优、持续时间更长,术后短期可能出现轻度的并发症,但术后并发症与1档相比无明显差异。

基于中红外波段的烷烃浓度遥测光学系统

为了实现对烷烃气体浓度的大范围灵活检测,提出一种基于卡塞格林系统的中红外遥测遥感的方法。对该光学系统的发射模块、接收模块和探测模块进行整体设计研究,基于卡塞格林系统结合3464 nm的中红外光源完成对烷烃浓度遥测遥感光学系统的设计。该光学系统需要实现对25~100 m大范围内目标的测量,设计了25 cm口径的光学遥测系统。针对卡塞格林系统存在光信号丢失的问题,采用透射式非球面准直结构,可以实现对不同距离目标的调焦;针对口径过大引起的视差问题,采用发射接收同轴的方式来消除较大的视差。实验结果表明,本系统能够对25~100 m的目标进行测量。主镜和次镜镀有中红外增强金膜,使系统的稳定性得到了显著提升。经过测试,系统的总体发射效率为86%,接收效率为75.8%。烷烃遥测遥感系统能够在大范围远距离上遥测气体浓度,使用方便、测量迅速,测量人员面对的风险低,能够保证整体光学系统的稳定性及作业检测的安全性。

近端胃切除术后胃食管反流病的研究进展

胃食管反流病(GERD)是一种常见的消化系统疾病,其病因复杂且反复发作,给临床医师带来了很大的困扰。近端胃切除术作为一种治疗胃癌等疾病的手术方法,破坏了贲门及周边的生理结构,可能导致术后残胃反酸、反流现象的发生,从而引发GERD。这种情况严重影响了患者的生活质量。本文主要对近端胃切除术后GERD的发病机制、治疗方法以及抗反流术式的进展进行了总结,旨在为近端胃切除术后GERD治疗方案的选择提供参考依据。

腰椎融合术后迟发性硬膜外血肿1例

患者,女,72岁,腰痛20余年,近2个月腰痛加剧伴左臀部、大腿后外侧及小腿外侧疼痛、麻木,于2023年10月9日以L_(4~5)椎间盘突出症收入院。有高血压、脂肪肝病史20余年。于2023年10月12日在全身麻醉下行L_(4~5)全椎板切除椎管减压+椎间盘切除椎间植骨融合内固定术。

低温胁迫后紫花苜蓿叶片光合作用的恢复特性研究

为探究低温解除后苜蓿光合作用恢复过程中的限制位点,以‘新牧4号’和‘甘农5号’2个品种紫花苜蓿为材料,测定其低温胁迫及恢复过程中苜蓿叶片光合活性的变化。结果表明,低温胁迫下2个苜蓿品种叶片叶绿素含量、净光合速率以及光系统Ⅱ(photosystemⅡ,PSⅡ)活性显著下降,非光化学淬灭系数(nonphotochemical quenching factor,NPQ)显著上升,但对光系统Ⅰ(photosystemⅠ,PSⅠ)的活性无显著影响;其中,‘甘农5号’叶绿素对低温更敏感,含量下降较多。室温恢复72 h后,2个品种苜蓿叶片PSⅡ的活性及净光合速率都有上升但均未恢复至处理前水平;NPQ缓慢下降至处理前水平,‘甘农5号’NPQ较‘新牧4号’更高,表明在恢复过程中仍有过剩光能需通过NPQ消耗。苜蓿叶片的电子传递链在低温下受抑制显著,恢复72 h后PSⅡ受体侧活性基本恢复至处理前,而PSⅡ供体侧活性显著下降。2个品种苜蓿单位反应中心捕获的用于电子传递的能量(energy captured by unit reaction center for electron transfer,ETO/RC)和单位反应中心捕获的用于还原QA的能量(energy captured by the unit reaction center for reducing QA,TRO/RC)在低温处理72 h后显著下降,解除低温后恢复至处理前水平,且2个品种无显著差异;2个苜蓿品种单位反应中心耗散掉的能量(energy dissipated by the unit reaction center,DIO/RC)未恢复至处理前水平,且‘甘农5号’在恢复72 h后DIO/RC显著升高。综上,低温胁迫显著伤害紫花苜蓿叶片光合机构,降低了光合速率,光合速率未恢复到处理前与PSⅡ的活性显著相关,限制光合作用恢复的位点在其供体侧,非光化学淬灭是恢复24 h过剩光能的主要分配途径。

机械活化协同固相法制备羧甲基多孔淀粉及其在粉末酱油中的应用

为获得一种绿色高效的羧甲基多孔淀粉制备工艺,本研究以酶解制得的多孔木薯淀粉为原料,氯乙酸钠为醚化剂,氢氧化钠为催化剂,采用机械活化协同固相醚化法制备羧甲基多孔淀粉,通过单因素实验探究各因素对羧甲基多孔淀粉取代度(Degree of substitution,DS)的影响,并探讨羧甲基多孔淀粉在酱油中的应用。结果表明,机械活化协同固相法制备羧甲基多孔淀粉的最佳工艺条件为:多孔淀粉与氯乙酸钠的物质的量之比为1:1,氢氧化钠质量分数为18.8%,球磨时间1.5 h,反应温度50℃,此条件下制备得到的羧甲基多孔淀粉取代度最高为0.2532。通过红外光谱仪(Infrared spectrometer,FTIR)、X-射线粉末衍射仪(X-ray powder diffractometer,XRD)和扫描电镜(Scanning electron microscope,SEM)等表征,进一步证实多孔淀粉发生了羧甲基化反应。随着羧甲基多孔淀粉DS的增大其冷水溶解度、吸水率和柠檬黄吸附量增大;当DS为0.2532时,羧甲基多孔淀粉的冷水溶解度达到64.94%,吸水率达到180.73%,柠檬黄吸附量达到2.5086 mg·g^(-1)。羧甲基多孔淀粉所制备的粉末酱油相比于木薯淀粉和多孔淀粉所制备的粉末酱油溶解性更好,吸潮性更低,氨基酸态氮含量更高,与原酱油最接近。因此,机械活化协同固相醚化法可有效制备羧甲基多孔淀粉,该法操作简单,绿色环保,取代高,为多孔淀粉的开发利用提供了科学依据。

Identification of cell surface markers for acute myeloid leukemia prognosis based on multi-model analysis

Given the extremely high inter-patient heterogeneity of acute myeloid leukemia(AML),the identification of biomarkers for prognostic assessment and therapeutic guidance is critical.Cell surface markers(CSMs)have been shown to play an important role in AML leukemogenesis and progression.In the current study,we evaluated the prognostic potential of all human CSMs in 130 AML patients from The Cancer Genome Atlas(TCGA)based on differential gene expression analysis and univariable Cox proportional hazards regression analysis.By using multi-model analysis,including Adaptive LASSO regression,LASSO regression,and Elastic Net,we constructed a 9-CSMs prognostic model for risk stratification of the AML patients.The predictive value of the 9-CSMs risk score was further validated at the transcriptome and proteome levels.Multivariable Cox regression analysis showed that the risk score was an independent prognostic factor for the AML patients.The AML patients with high 9-CSMs risk scores had a shorter overall and event-free survival time than those with low scores.Notably,single-cell RNA-sequencing analysis indicated that patients with high 9-CSMs risk scores exhibited chemotherapy resistance.Furthermore,PI3K inhibitors were identified as potential treatments for these high-risk patients.In conclusion,we constructed a 9-CSMs prognostic model that served as an independent prognostic factor for the survival of AML patients and held the potential for guiding drug therapy.

响应面法维生素E/淀粉酯微胶囊制备工艺的优化及表征

以机械活化共反应剂法制备的乙酸辛酸淀粉酯(OAS)为壁材、维生素E为芯材,通过响应面优化实验确定微胶囊制备最佳工艺条件;利用FT-IR、SEM及粒度分布仪等对制备的微胶囊进行分析。结果表明,响应面优化实验的最佳条件为:进口温度为185℃、固形物质量分数为8.9%、芯壁比为1∶3.75,在此条件下所制备的微胶囊的包埋率为88.61%。FT-IR分析结果表明,维生素E成功实现包埋。SEM分析结果表明,维生素E/乙酸辛酸淀粉酯微胶囊表面光滑呈球形,存在一定的孔洞。粒径分析结果表明,微胶囊粒径较OAS有所增大,这与SEM表征结果相一致。

痛风与高尿酸血症患者膳食方式新理念

痛风和高尿酸血症患病率逐年升高,疾病负担随之加重。对患者或高危人群的膳食进行合理干预有利于降低患病率,并提高患者慢病自我管理的质量。本文通过对痛风和高尿酸血症患者膳食方式的研究进展进行分析,推荐遵循目前较为公认的健康饮食模式来进行长期的膳食管理,而并非单一的区别“好”或“坏”的食物,或过度的低嘌呤饮食方式,以期更好地指导痛风和高尿酸血症患者的自我管理。

ICU患者并发导管相关血流感染预测模型的构建与验证

目的探讨重症监护病房(ICU)患者并发导管相关血流感染(CRBSI)的危险因素,并构建其预测模型。方法选取2021年2月至2023年2月广东省第二人民医院收治的402例ICU住院患者,其中2021年2月至2022年9月的280例患者作为训练集构建预测模型,2022年10月至2023年2月的122例患者作为验证集进行外部验证。单因素和多因素logistic回归分析患者发生CRBSI的危险因素,构建基于危险因素的联合预测模型并绘制列线图,验证其准确性。结果训练集280例患者中有15例发生CRBSI(5.4%),验证集122例患者中有8例发生CRBSI(6.6%),2组CRBSI发生率差异无统计学意义(χ^(2)=0.227,P=0.634)。训练集中多因素分析显示,导管留置时间、导管滑动/滑出、白细胞、白蛋白是ICU患者发生CRBSI的独立危险因素(P<0.05)。列线图模型验证结果显示,训练集与验证集的C-index分别为0.904和0.877,曲线下面积分别为0.845和0.822。决策曲线分析显示,列线图在训练集和验证集有较好的临床获益性。结论基于CRBSI危险因素构建的列线图可预测ICU患者发生CRBSI风险,能帮助医护人员及时采取有效的干预措施。

地黄饮子治疗痴呆效果研究的Meta分析

目的:系统评价地黄饮子加减及联合常规西药治疗痴呆的有效性。方法:计算机检索中国知网、中国生物医学文献数据库、万方数据库、维普数据库、PubMed、Web of science、Embase数据库中地黄饮子加减及联合常规西药治疗痴呆的随机对照试验,检索时间为各数据库建库至2023年9月。筛选符合纳入标准的文献进行质量评价,提取相应资料,采用RevMan5.3软件进行Meta分析。结果:共纳入文献21篇,1647例患者。Meta分析结果显示,治疗组的临床疗效高于对照组[OR=4.22,95%CI(3.22,5.52),P<0.00001],治疗组改善痴呆的MMSE评分高于对照组[MD=3.88,95%CI(1.98,5.77),P<0.0001],治疗组改善痴呆的HDS评分高于对照组[MD=3.86,95%CI(1.85,5.88),P<0.01],治疗组改善痴呆的ADL评分低于对照组[MD=-2.79,95%CI(-4.56,-1.02),P<0.01]。治疗组痴呆的不良反应发生率未明显低于对照组[OR=0.50,95%CI(0.25,0.99),P=0.05>0.01]。结论:地黄饮子加减及联合常规西药治疗痴呆的总有效率高于单纯常规西药治疗,且可改善简易精神状态检查量表(mini-mental state examination,MMSE)、长谷川痴呆量表(hastgawa dementia scale,HDS)和日常生活能力量表(activity of daily living scale,ADL)评分。本研究存在一定的局限性,仍需多中心、大样本、高质量的研究补充论证。

艺术体操专项灵敏素质训练方法探究

艺术体操是一项身体动作和器械动作紧密结合的运动项目,运动员在高质量地完成成套动作的整个过程中,对身体和器械运动的方位、角度有着严格的要求。在进行不同项目训练时,对灵敏素质要求不同,从而导致训练方法不同。以高校艺术体操专项组训练为研究对象,对运动灵敏素质训练主要体现和训练方法进行探讨分析,在了解现有训练方法的基础上为艺术体操训练提供更有效的灵敏素质训练方法。调动训练者训练的积极性和主动性,从而使艺术体操灵敏训练趋于多样性与科学化。

Mapping the metabolic responses to oxaliplatin-based chemotherapy with in vivo spatiotemporal metabolomics

Adjuvant chemotherapy improves the survival outlook for patients undergoing operations for lung metastases caused by colorectal cancer (CRC). However, a multidisciplinary approach that evaluates several factors related to patient and tumor characteristics is necessary for managing chemotherapy treatment in metastatic CRC patients with lung disease, as such factors dictate the timing and drug regimen, which may affect treatment response and prognosis. In this study, we explore the potential of spatial metabolomics for evaluating metabolic phenotypes and therapy outcomes during the local delivery of the anticancer drug, oxaliplatin, to the lung. 12 male Yorkshire pigs underwent a 3 h left lung in vivo lung perfusion (IVLP) with various doses of oxaliplatin (7.5, 10, 20, 40, and 80 mg/L), which were administered to the perfusion circuit reservoir as a bolus. Biocompatible solid-phase microextraction (SPME) microprobes were combined with global metabolite profiling to obtain spatiotemporal information about the activity of the drug, determine toxic doses that exceed therapeutic efficacy, and conduct a mechanistic exploration of associated lung injury. Mild and subclinical lung injury was observed at 40 mg/L of oxaliplatin, and significant compromise of the hemodynamic lung function was found at 80 mg/L. This result was associated with massive alterations in metabolic patterns of lung tissue and perfusate, resulting in a total of 139 discriminant compounds. Uncontrolled inflammatory response, abnormalities in energy metabolism, and mitochondrial dysfunction next to accelerated kynurenine and aldosterone production were recognized as distinct features of dysregulated metabolipidome. Spatial pharmacometabolomics may be a promising tool for identifying pathological responses to chemotherapy.

Printability disparities in heterogeneous material combinations via laser directed energy deposition:a comparative study

Additive manufacturing provides achievability for the fabrication of bimetallic and multi-material structures;however,the material compatibility and bondability directly affect the parts’formability and final quality.It is essential to understand the underlying printability of different material combinations based on an adapted process.Here,the printability disparities of two common and attractive material combinations(nickel-and iron-based alloys)are evaluated at the macro and micro levels via laser directed energy deposition(DED).The deposition processes were captured using in situ high-speed imaging,and the dissimilarities in melt pool features and track morphology were quantitatively investigated within specific process windows.Moreover,the microstructure diversity of the tracks and blocks processed with varied material pairs was comparatively elaborated and,complemented with the informative multi-physics modeling,the presented non-uniformity in mechanical properties(microhardness)among the heterogeneous material pairs was rationalized.The differences in melt flow induced by the unlike thermophysical properties of the material pairs and the resulting element intermixing and localized re-alloying during solidification dominate the presented dissimilarity in printability among the material combinations.This work provides an in-depth understanding of the phenomenological differences in the deposition of dissimilar materials and aims to guide more reliable DED forming of bimetallic parts.

Physical mechanism of oxygen diffusion in the formation of Ga_(2)O_(3) Ohmic contacts

The formation of low-resistance Ohmic contacts in Ga_(2)O_(3) is crucial for high-performance electronic devices. Conventionally, a titanium/gold(Ti/Au) electrode is rapidly annealed to achieve Ohmic contacts, resulting in mutual diffusion of atoms at the interface. However, the specific role of diffusing elements in Ohmic contact formation remains unclear.In this work, we investigate the contribution of oxygen atom diffusion to the formation of Ohmic contacts in Ga_(2)O_(3). We prepare a Ti/Au electrode on a single crystal substrate and conduct a series of electrical and structural characterizations.Using density functional theory, we construct a model of the interface and calculate the charge density, partial density of states, planar electrostatic potential energy, and I–V characteristics. Our results demonstrate that the oxygen atom diffusion effectively reduces the interface barrier, leading to low-resistance Ohmic contacts in Ga_(2)O_(3). These findings provide valuable insights into the underlying mechanisms of Ohmic contact formation and highlight the importance of considering the oxygen atom diffusion in the design of Ga_(2)O_(3)-based electronic devices.

Light-modulated graphene-based φ_(0) Josephson junction and -φ_(0) to φ_(0) transition

We investigate the chiral edge states-induced Josephson current–phase relation in a graphene-based Josephson junction modulated by the off-resonant circularly polarized light and the staggered sublattice potential.By solving the Bogoliubov–de Gennes equation,a φ_(0) Josephson junction is induced in the coaction of the off-resonant circularly polarized light and the staggered sublattice potential,which arises from the fact that the center of-mass wave vector of Cooper pair becomes finite and the opposite center of-mass wave vector to compensate is lacking in the nonsuperconducting region.Interestingly,when the direction of polarization of light is changed,-φ_(0) to φ_(0) transition generates,which generalizes the concept of traditional 0–πtransition.Our findings provide a purely optical way to manipulate a phase-controllable Josephson device and guidelines for future experiments to confirm the presence of graphene-based φ_(0)Josephson junction.