1-MCP与MT联合处理对芒果保鲜效果的影响

为探究1-甲基环丙烯(1-MCP)与褪黑素(MT)联合处理对芒果保鲜效果的影响,该研究用0.1 mg/L 1-MCP和0.2 mmol/L MT联合处理芒果后,于25℃贮藏10 d,每2 d取样测定相关指标。结果显示:1-MCP和MT联合处理可以延缓芒果果皮叶绿素降解和类胡萝卜素含量升高,在贮藏第10天,处理组的果皮叶绿素为0.078 mg/g,是对照组的5.27倍;延缓了果肉L*值的下降和a*、b*值的升高,抑制原果胶降解和可溶性果胶含量的升高,贮藏第6天处理组的原果胶含量比对照高2.53倍,而可溶性果胶含量比对照低44.04%,同时在贮藏前期显著抑制了多聚半乳糖醛酸酶(PG)和纤维素酶(Cx)活性,降低了β-半乳糖苷酶(β-Gal)活性,并且维持了果肉更完整的细胞结构,但果肉类黄酮含量在贮藏中期显著低于对照。综上,1-MCP和MT联合处理保持了芒果良好的外观品质,延缓了细胞壁物质的降解,提高了货架期品质。

50mT静磁场试验装置的研制和性能验证

为了满足有源植入式医疗器械标准中静磁场试验要求,研制了一款静磁场抗扰度试验装置。在输入电流约4.75 A条件下,该装置的磁通密度可以达到50 mT,且试验均匀域的磁通密度均匀性偏差达到2.8%。在0.055~50mT范围内,磁通密度的线性度达到了0.6%。该装置还可以实现对电压、电流、时间、温度以及电磁场曝露等参数进行有效地监控。该研究为有源植入式医疗器械的静磁场抗扰度试验提供了理论和技术支撑。

产教融合背景下基于MTS理论的金融知识学习及教学模式研究

在产教融合背景下,金融类课程的教学模式正向问题导向型转变。金融知识学习及教学通过产学协同,并匹配不同学生的学习特征和所要传授的知识特征,实现人才培养质量的提升。产教融合的模式中,混合型师资队伍建设是核心环节,通过案例研究,基于多团队系统理论,探讨产教融合背景下如何构建由校内教师、行业专家和学生组成的多元化教学团队,并分析其运行机制和效果;同时,基于学习模型的教学支持与模式创新,结合学生学习特征,对主要教学方法进行体系化梳理,并优化教学方法,形成教学方案。

基于VTI介质海洋CSEM和MT数据联合反演的黄海海相残留盆地深部结构研究

黄海海相残留盆地因其地层结构和深部地质构造的复杂性,一直是我国海洋地球科学的一项研究重点,虽然针对该研究区已开展了一系列的地球物理调查,但由于高速碳酸盐岩层对地震波存在着一定的屏蔽作用,致使该海域深部地震资料品质受到较大影响.海洋电磁法不受高速屏蔽层影响,有利于获得高速屏蔽层内部及其下方的深部结构信息.海洋可控源电磁法(Controlled source electromagnetic method,CSEM)和海洋大地电磁测深(Magnetotelleric,MT)能够提供海底电性结构的互补信息,较于单一的电磁方法,二者联合可获得更为准确的海底电性分布.本文提出了基于乘积目标函数的层状垂直各向异性(Vertical anisotropic,VTI)介质海洋可控源电磁和大地电磁资料联合反演方法,该方法在迭代过程中根据数据的拟合情况自适应调整CSEM和MT数据的权重和正则化因子的权重,反演参数包括海底介质的横向电阻率、垂向电阻率和地层厚度.以南黄海地质地球物理资料为例,建立浅水环境地电模型,并结合浅水环境的高噪声背景特点进行合成数据模型测试及分析.将本文所提出算法应用于理论模型合成数据和南黄海实测资料反演,结果表明,较于单独的海洋CSEM和MT反演,联合反演方法能够较准确地重构海底地层的电性分布,提高对海底地层各向异性电阻率的分辨能力.

基于调车工况的MT-2缓冲器容量需求仿真分析

为了分析MT-2缓冲器在调车连挂作业时的容量需求问题,基于摩擦式缓冲器非线性力学特性及车辆调车冲击受力特点,建立了铁道货车纵向冲击动力学模型,对调车过程中不同车辆质量、不同速度、不同编组方式及不同车体刚度等工况下MT-2缓冲器容量需求进行了分析。研究结果表明:缓冲器做功与车辆质量和连挂速度的平方成正比,冲击车和被冲击车数量都大于2辆时冲击面缓冲器的容量需求将与车辆数量无关。对同时考虑质量、速度、编组方式、车体刚度的缓冲器容量需求值进行了函数拟合,完成了比例系数κ、μ和λ的求解;不同车辆数量之间冲击时,不同车钩号的缓冲器做功值大小不一,在冲击面车钩号的缓冲器做功值均为最大,沿着冲击面前、后的车钩号逐渐递减,调车冲击时计算容量需求值时应不考虑车体刚度,以重车冲击重车模式时冲击面的缓冲器容量需求为准。

基于MT-CNN的矿井带式输送机输煤量检测技术

为实现矿井带式输送机输煤量检测的信息化、智能化,提出基于MT-CNN的矿井带式输送机输煤量检测技术。为了全面提升输煤量检测技术,从而提高矿井效益,选取了多任务卷积神经网络(MT-CNN)对检测目标进行多核心识别检测,优化了图像直线信息和边缘信息的提取效率,构建了良好的网络层次结构,优化了信息连接通道,从而全面提高图像识别分析和数据检测处理的效果。通过MT-CNN技术对输煤量的轮廓形态和荷载状态进行分析运算,经过图像样本数据训练获取矿井带式输送机输煤量的相关数据。研究结果表明,该技术能够有效提高输煤量图像识别的真实性,而检测时间缩短49%,计算结果准确率提高到98%,有效提高了输煤量检测的效率和准确度,具有较好的应用性能和良好的使用效果。加强矿井带式输送机的输煤量检测,可以为后续研究提供依据,很大程度上推动了相关技术发展,实现矿井信息化、智能化、现代化发展。

5G集约化VoLTE短信网关MT成功率提升方案研究

导致集约化VoLTE短信网关上线后MT成功率较割接前下降的三种主要原因,包括VoLTE网关对短信中心长会话保持参数识别错误、多业务处理机之间缺乏有效的协同机制、对MT短信ENUMDNS查询量过大。实施针对性改进措施后,成功率得到了显著提升。

基于MT7620A的智慧监控网关设计

针对网络摄像机不具备远程监控能力的问题,基于MT7620A设计了一种支持远程监控的智慧网关。网关使用MT7620A作为主控芯片,搭载OpenWrt系统。通过创建ONVIF客户端与同一局域网中支持ONVIF协议的监控设备进行通信,实现设备发现、信息获取、云台控制和视频流读取等功能;网关与云平台通过MQTT协议实现信令交互,云平台可以向网关发送设备管理、云台控制和视频流读取等命令;网关通过数据处理模块对命令进行解析和协议转换,实现对设备的管理,以及对监控设备云台的控制和视频流读取。网关在使用FFMPEG接口获取视频流之后,通过Socket TCP与云平台建立连接并发送视频流,保证视频流远程传输的稳定可靠。网关配有4G通信模块,避免了接入互联网受到有线网络通信的限制,双重通信方式更加有效地保障了网络传输。测试结果表明,所设计的网关能够支持云平台实现对设备的远程监控和控制。

Splenectomy: Indications in the General Surgery Department of Ignace Deen Hospital

Introduction: Splenectomy is the surgical removal of the spleen. It can be performed during various pathologies, ranging from abdominal trauma to hemoglobinopathies. The progress made in the knowledge of the immune functions of the spleen and the fear of post-splenectomy infectious complications have favored the development of surgical or non-surgical splenic preservation techniques calling into question the dogma of splenectomy. The aim of this study was to determine the indications for splenectomy. Methodology: This was a retrospective, descriptive study lasting 5 years in the general surgery department of the Ignace Deen National Hospital. All files of splenectomized patients were included, our variables were clinical, therapeutic and progressive. Results: We collected 42 cases of splenectomies out of the 2478 surgical procedures performed, representing 1.7% of the department’s surgical activities. The average age was 44 years. The age group of 41 to 50 years was the most represented, i.e. 26% (n = 11) of cases. Sex ratio = 1. Abdominal pain was the reason for consultation in patients, i.e. 100% (n = 42) of cases. The antecedents were dominated by recurrent malaria with 52.3% (n = 22) of cases, then recurrent anemia in 21% (n = 9), and 16.7% (n = 7) had sickle cell disease. Splenomegaly was found in 31 patients, or 73.6%. Ultrasound was performed in all patients. The indications for splenectomy were: isolated splenomegaly with risk of rupture (38%, n = 16), hypersplenism (26%, n = 11) and trauma to the spleen (19.04%, n = 8). Total splenectomy was performed in all cases. The surgical consequences were favorable in 85.7%, (n = 36) with morbidity of 14% (n = 6) and mortality of 9.52% (n = 4). The average length of hospitalization was 10.4 days with extremes of 1 and 22 days. Conclusion: Splenectomy constitutes a relatively common surgical procedure in our context. The indications for splenectomy were isolated splenomegaly with risk of rupture, hypersplenism and trauma to the spleen and total splenectomy was the rule.

Predictors of portal vein thrombosis after splenectomy in patients with cirrhosis

BACKGROUND Portal vein thrombosis(PVT)is a commonthsn complication after splenectomy in patients with cirrhosis.However,the predictors of postoperative PVT are not known.AIM To investigate the predictors of PVT after splenectomy in patient with cirrhosis.METHODS A total of 45 patients with cirrhosis who underwent splenectomy were consecutively enrolled from January 2017 to December 2018.The incidence of PVT at 1 months,3 months,and 12 months after splenectomy in patients with cirrhosis was observed.The hematological indicators,biochemical and coagulation parameters,and imaging features were recorded at baseline and at each observation point.The univariable,multivariable,receiver operating characteristic curve and timedependent curve analyses were performed.RESULTS The cumulative incidence of PVT was 40.0%,46.6%,and 48.9%at 1 months,3 months,and 12 months after splenectomy.Multivariable analysis showed that portal vein diameter(PVD)≥14.5 mm and monthsdel end-stage liver disease(MELD)score>10 were independent predictors of PVT at 1 months,3 months,and 12 months after splenectomy(P<0.05).Time-dependent curve showed that the cumulative incidence of PVT was significantly different between patients with MELD score≤10 and>10(P<0.05).In addition,the cumulative incidence of PVT in the PVD≥14.5 mm group was significantly higher than that in the PVD<14.5 mm group(P<0.05).CONCLUSION Wider PVD and MELD score>10 were independent predictors of PVT at 1 months,3 months,and 12 months after splenectomy in patient with cirrhosis.

Robot-assisted partial splenectomy for benign splenic tumors:Four case reports

BACKGROUND Robotic-assisted partial splenectomy(RAPS)is a superior approach for treating splenic cysts and splenic hemangiomas,as it preserves the immune function of the spleen and reduces the risk of overwhelming post splenectomy infection.Curren-tly,there are no standardized guidelines for performing a partial splenectomy.CASE SUMMARY Four patients with splenic cysts or splenic hemangiomas were treated by RAPS.Critical aspects with RAPS include carefully dissecting the splenic pedicle,accurately identifying and ligating the supplying vessels of the targeted segment,and ensuring precise hemostasis during splenic parenchymal transection.Four successful RAPS cases are presented,where the tumors were removed by pret-reating the splenic artery,dissecting and ligating the corresponding segmental vessels of the splenic pedicle,transecting the ischemic segment of the spleen,and using electrocautery for optimal hemostasis.Four patients underwent successful surgeries with minimal bleeding during the procedure,and there were no signs of bleeding or recurrence postoperatively.CONCLUSION Four cases confirm the feasibility and superiority of RAPS for the treatment of benign splenic tumors.

CSAMT、MT等电磁法在矿山地质勘探中技术参数研究

目前,在矿山地质勘探中广泛采用CSAMT、MT等电磁法,但该类电磁法均存在电磁干扰影响因素,都存在其所对应地质条件的最佳工作技术参数,为了降低野外数据采集工作过程中电磁干扰并达到最佳工作目标任务要求,本文通过作者十几年来积累的关于CSAMT、MT在各种不同矿山地质条件下的工作经验及试验结论,总结得出该类电磁法在一定地质条件下的最佳工作技术参数,将为今后在不同矿山、不同地质条件下开展该相关方法提供参考示范。

抗肿瘤肽Mt5对人肝癌细胞增殖和凋亡的影响及机制

目的探讨抗肿瘤肽Mt5通过磷脂酰肌醇-3激酶(PI3K)/蛋白激酶B(AKT)信号通路对人肝癌细胞增殖与凋亡的影响。方法采用pymol构建Mt5的三维可视化结构示意图,Prot Param分析Mt5的正电荷和疏水性,NPS分析Mt5的α-螺旋所占比例;运用实时无标记细胞分析(RTCA)技术检测不同浓度Mt5(50 mg/L、100mg/L、200 mg/L、400 mg/L)作用后的HepG2细胞活力;通过实时荧光定量PCR法(qRT-PCR)法检测不同浓度Mt5(25 mg/L、50 mg/L、100 mg/L)作用后HepG2细胞中PI3K、AKT信使RNA(mRNA)表达;以Western blot法检测不同浓度Mt5(25 mg/L、50 mg/L、100 mg/L)作用后凋亡相关蛋白B细胞淋巴瘤-2蛋白(Bcl-2)、Bcl-2相关X蛋白(bax)和PI3K、AKT蛋白表达。结果生物学信息结果表明,Mt5的正电荷为+8,疏水性为0.588,α-螺旋度为84.62%;RTCA结果显示Mt5不同浓度处理组作用后,HepG2细胞指数随着Mt5浓度的增大和时间的延长逐渐降低至0以下;qPCR结果显示,Mt5组HepG2细胞中PI3K和AKT mRNA较阴性对照组表达降低(P<0.05),bax蛋白表达较阴性对照组升高(P<0.05),且呈浓度依赖性;Western blot结果显示,Mt5组HepG2细胞中Bcl-2、PI3K及AKT蛋白表达较阴性对照组降低(P<0.05),且呈浓度依赖性。结论Mt5可抑制人肝癌细胞增殖及诱导细胞凋亡,其机制可能与抑制PI3K/AKT信号通路有关。

ZNT1 Involves Cuproptosis through Regulating MTF1-conduced Expression of MT1X under Copper Overload

Industrial activities such as smelting emissions,mineral combustion and industrial wastewater discharge might lead to copper pollution in the environment.This kind of copper pollution has harmful effects on aquatic o rganisms,plants and animals through direct or indirect exposure.However,the current understanding of the toxicity of copper is rather limited.Copper overload can perturb intracellular homeostasis and induce oxidative stress and e ven cell death.Recently,cuproptosis has been identified as a copper-dependent form of cell death induced by o xidative stress in mitochondria.We uncover here that zinc transporter 1(ZNT1)is an important regulator involved in cuproptosis.Firstly,we established the copper overload-induced cell death model with the overexpression of copper importer SLC31A1 in HeLa cells.Using this model,we conducted unbiased genome-wide CRISPR-Cas9 screens in cells treated with copper.Our results revealed a significant enrichment of ZNT1 gene in both library A and library B plasmids.Knocking out of ZNT1 in HeLa cells notably prevented cuproptosis.Subsequent knockout of metal transcription factor 1(MTF1)in ZNT1-deficient cells nearly abolished their ability to resist copper-induced cell death.However,overexpression of metallothionein 1X(MT1X)in the double-knockout cells could p artially restored the resistance to cuproptosis by loss of MTF1.Mechanistically,knockout of ZNT1 could promote MT1X expression by activating MTF1.As a consequence,the interaction between MT1X and copper was e nhanced,reducing the flow of copper into mitochondria and eliminating mitochondria damage.Taken together,this study reveals the important role of ZNT1 in cuproptosis and shows MTF1-MT1X axis mediated resistance to c uproptosis.Moreover,our study will help to understand the regulatory mechanism of cellular and systemic copper homeostasis under copper overload,and present insights into novel treatments for damages caused by both genetic copper overload diseases and environmental copper contamination.

Will partial splenic embolization followed by splenectomy increase intraoperative bleeding?

BACKGROUND Partial splenic embolization(PSE)has been suggested as an alternative to splenectomy in the treatment of hypersplenism.However,some patients may experience recurrence of hypersplenism after PSE and require splenectomy.Currently,there is a lack of evidence-based medical support regarding whether preoperative PSE followed by splenectomy can reduce the incidence of complications.AIM To investigate the safety and therapeutic efficacy of preoperative PSE followed by splenectomy in patients with cirrhosis and hypersplenism.METHODS Between January 2010 and December 2021,321 consecutive patients with cirrhosis and hypersplenism underwent splenectomy at our department.Based on whether PSE was performed prior to splenectomy,the patients were divided into two groups:PSE group(n=40)and non-PSE group(n=281).Patient characteristics,postoperative complications,and follow-up data were compared between groups.Propensity score matching(PSM)was conducted,and univariable and multivariable analyses were used to establish a nomogram predictive model for intraoperative bleeding(IB).The receiver operating characteristic curve,Hosmer-Lemeshow goodness-of-fit test,and decision curve analysis(DCA)were employed to evaluate the differentiation,calibration,and clinical performance of the model.RESULTS After PSM,the non-PSE group showed significant reductions in hospital stay,intraoperative blood loss,and operation time(all P=0.00).Multivariate analysis revealed that spleen length,portal vein diameter,splenic vein diameter,and history of PSE were independent predictive factors for IB.A nomogram predictive model of IB was constructed,and DCA demonstrated the clinical utility of this model.Both groups exhibited similar results in terms of overall survival during the follow-up period.CONCLUSION Preoperative PSE followed by splenectomy may increase the incidence of IB and a nomogram-based prediction model can predict the occurrence of IB.

养殖水域Cu^(2+)胁迫对虹鳟MT2基因表达模式的影响

为了探究水体中铜离子胁迫对虹鳟(Oncorhynchus mykiss)MT2基因表达模式的影响,开发Metallothioneins作为检测水域生态中重金属铜污染的分子标志,该研究利用TA克隆法获得了虹鳟MT2基因的CDS序列,检测了MT2基因在虹鳟不同组织中的表达模式,以及Cu^(2+)胁迫(Cu^(2+)浓度75、150和300μg/L)后1、2、3和4 d和胁迫恢复1、2 d时间点的MT2基因表达动态。结果表明,虹鳟MT2基因CDS区长186 bp,编码62个氨基酸,具有典型的半胱氨酸(Cys)-X(1~3个)-半胱氨酸结构,属不稳定亲水性蛋白。虹鳟MT2基因序列与大西洋鲑的同源性最高且在肝脏中表达量最高,其次是脑和肠道。胁迫试验结果显示,MT2基因在肝脏和鳃中呈现先升高后降低的趋势,在头肾、脾脏和脑中呈现逐渐升高的趋势,且呈现一定的剂量依赖性,肠道MT2基因在胁迫2、3和4 d被显著抑制。胁迫恢复后,处理组肝脏、头肾、鳃、脑MT2基因表达量仍显著升高。综上,虹鳟MT2基因能在不同组织中被Cu^(2+)诱导表达,推测MT2基因在虹鳟抗重金属毒性中可能发挥着重要作用,且MT2基因表达量与铜离子的浓度相关,可以作为分子生物标志检测水域生态中的重金属铜污染。

Assessment of sediment connectivity using modelling and field-based approaches in the Slavíč River catchment(MoravskoslezskéBeskydy Mts,Czech Republic)

Mountain streams act as conveyors of sediments within the river continuum,where the physical transport of sediments between river reaches through the catchment or between individual parts(e.g.,between hillslopes and channels)of the catchment is assumed.This study focused on sediment connectivity analysis in the SlavíčRiver catchment in the MoravskoslezskéBeskydy Mts in the eastern part of the Czech Republic.The connectivity index and connectivity index target modelling were combined with an analysis of anthropogenic interventions.Additionally,field mapping,grain size of bed sediments and stream power analysis were used to obtain information about connectivity in the catchment.Based on the analysis and obtained results,terrain topography is the current main driving factor affecting the connectivity of sediment movement in the SlavíčRiver catchment.However,the modelling provided valuable information about high sediment connectivity despite different recent land use conditions(highly forested area of the catchment)than those in historical times from the 16th to 19th centuries when the SlavíčRiver catchment was highly deforested and sediment connectivity was probably higher.The analysis of anthropogenic interventions,field mapping,grain size of bed sediments and stream power analysis revealed more deceleration of sediment movement through the catchment,decreased sediment connectivity with bed erosion,and gradual river channel process transformation in some reaches.Field mapping has identified various natural formations and human-induced changes impacting the longitudinal and lateral connectivity in the SlavíčRiver.For instance,embankments along 48%of the river's length,both on the right and left banks,significantly hinder lateral sediment supply to the channel.Stream power index analysis indicates increased energy levels in the flowing water in the river's upper reaches(up to 404.8 W m^(-2)).This high energy is also observed in certain downstream sections(up to 337.6 W m^(-2)),where it is influenced by human activities.These conditions lead to intensified erosion processes,playing a crucial role in sediment connectivity.Similar observations were described in recent studies that pointed out the long-term human interventions on many streams draining European mountains,where a decrease in sediment connectivity in these streams is linked with sediment deficits and the transformation of processes forming channels.

MT-1207对小鼠血糖、血脂和动脉粥样硬化的作用

目的研究MT-1207对小鼠血糖、血脂和动脉粥样硬化的作用。方法载脂蛋白E(ApoE)基因敲除(ApoE^(-/-))小鼠分别给予普通饲料、氯沙坦含药饲料和MT-1207含药饲料,给药剂量为30 mg/kg,测定小鼠的体质量、血糖和血脂指标,并评价动脉粥样硬化的斑块面积。对8周龄的雄性C57小鼠给予高脂饲料,每天以30mg/kg的剂量灌胃MT-1207和氯沙坦,考察小鼠的体质量、血糖和血脂的水平,进一步评价MT-1207对血糖、血脂的作用。结果长期MT-1207饲料给药和氯沙坦饲料给药的ApoE^(-/-)小鼠体质量增长更快,但血糖和血脂的水平没有显著改善,动脉粥样硬化的斑块面积也无明显变化。MT-1207和氯沙坦对高脂饮食的C57小鼠血糖、血脂均无明显改善作用。结论MT-1207和氯沙坦对血糖、血脂以及动脉粥样硬化没有改善作用,不会加重动脉粥样硬化。

矿用卡车MT5500电动轮典型故障分析及检修工艺优化

介绍了MT5500矿用卡车电动轮装配工艺的改进和密封设计的优化,旨在解决牵引电机压盖螺栓断裂和漏油故障问题;通过调整装配工艺和改进密封设计,提高了电动轮的使用寿命,降低了配件更换频率和检修工时。应用表明:新工艺的应用不仅提高了卡车的出动率,还降低了维修的劳动强度。

Gene Xpert MTB/RIF技术在结核病诊断中的应用

目的探讨Gene Xpert MTB/RIF技术在结核分枝杆菌(MTB)快速检测中的应用价值。方法收集2020年1月至2022年10月在南昌市第九医院就诊的疑似结核病患者送检的314例痰样本,分别采用Gene XpertMTB/RIF技术、抗酸染色法以及液体培养法进行检测,比较3种检测方法MTB阳性检出率,并以液体培养法检测结果为“金标准”,评估Gene Xpert MTB/RIF技术对MTB的检测效能。结果314例样本经GeneXpertMTB/RIF技术、抗酸染色法和结核分枝杆菌液体培养法检测,其阳性率分别为36.94%、12.10%和36.31%,Gene Xpert MTB/RIF技术和液体培养法MTB的阳性检出率高于抗酸染色法,差异有统计学意义(P<0.05)。以液体培养法为“金标准”,GeneXpertMTB/RIF技术MTB的检测敏感度为95.61%,特异度为96.50%;抗酸染色法的检测敏感度为31.58%,特异度为99.00%;Gene Xpert MTB/RIF技术的敏感度高于抗酸染色法,差异有统计学意义(P<0.05)。经Kappa分析发现Gene Xpert MTB/RIF技术与液体培养法检测MTB的一致性好(Kappa=0.918),而抗酸染色法与液体培养法检测结果的一致性较差(Kappa=0.357)。相比抗酸染色法,Gene XpertMTB/RIF技术有更高的正确检出率,联合使用可有效降低MTB的漏检率。结论GeneXpertMTB/RIF技术在MTB检测中具有敏感度高、特异性好等特点,有较高的临床应用价值。