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利用PEG实验确定女性巨泌乳素cut-off值及比较分析
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作者 宋胜男 陈陆 +3 位作者 刘雨珩 陈怡菲 翟燕红 曹正 《标记免疫分析与临床》 2025年第6期1233-1236,1289,共5页
目的利用聚乙二醇(PEG)沉淀实验,确定本实验室所应用的中国亚辉龙公司的iFlash-3000型化学发光免疫分析仪及相关配套试剂检测巨泌乳素的cut-off值。方法在2024年8月至2024年9月检测的泌乳素1619例标本中,收集泌乳素升高标本206例,进行PE... 目的利用聚乙二醇(PEG)沉淀实验,确定本实验室所应用的中国亚辉龙公司的iFlash-3000型化学发光免疫分析仪及相关配套试剂检测巨泌乳素的cut-off值。方法在2024年8月至2024年9月检测的泌乳素1619例标本中,收集泌乳素升高标本206例,进行PEG确认实验后进行分析,利用ROC曲线计算出cut-off值。结果本实验室巨泌乳素阳性率为12.73%。根据数据分析,PEG结果可分为3组,其中149例(72.33%)为单体泌乳素组,22例(10.68%)为混合泌乳素组,35例(16.99%)为巨泌乳素组。非单泌乳素组与单泌乳素组Youden指数下,当cut-off值为1086.95mIU/L时,灵敏度为77.1%,特异性为64.9%;非巨泌乳素组与巨泌乳素组Youden指数下,当cut-off值为1154.59mIU/L时,灵敏度为68.4%,特异性为70.5%。结论iFlash-3000型化学发光免疫分析仪及配套试剂检测泌乳素与PEG实验结果呈正相关;利用实验室cut-off值与临床信息相互认知才是判断巨泌乳素血症的有效方式。 展开更多
关键词 泌乳素检测 iFlash-3000 PEG实验 CUT-off
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用于lift-off工艺的电子束蒸发设备设计及工艺研究
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作者 胡凡 张双景 +3 位作者 杨露 王建青 王栋 于超文 《中国集成电路》 2025年第7期78-82,共5页
本研究基于剥离(lift-off)工艺,采用电子束蒸发设备设计原理,搭建了一台蒸发距离为1500 mm的M67130-1/UM型高精度多层金属蒸镀设备,并开展了相关工艺基础研究。研究结果表明,Al、Ge、NiGr金属薄膜厚度分布规律呈现沿伞架中心向伞架边缘... 本研究基于剥离(lift-off)工艺,采用电子束蒸发设备设计原理,搭建了一台蒸发距离为1500 mm的M67130-1/UM型高精度多层金属蒸镀设备,并开展了相关工艺基础研究。研究结果表明,Al、Ge、NiGr金属薄膜厚度分布规律呈现沿伞架中心向伞架边缘逐渐变薄的规律,而Ni薄膜基片呈现中间厚两边薄的特征;蒸发功率与蒸发材料及蒸发状态相关,其中Ge的蒸发功率最大,Ni的最低;合理设计修正板可显著改善膜层均匀性,经优化后制备的Al、Ge、NiGr、Ni金属薄膜片间均匀性分别由9.61%、12.48%、7.52%和12.22%提高至1.49%、2.71%、1.15%和1.62%,均控制在3%以内。 展开更多
关键词 电子束蒸发 LIFT-off 修正板 均匀性
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金属阳离子对OFF分子筛晶体形貌及其甲醇制烯烃性能的影响
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作者 马多征 刘闯 王振东 《化学反应工程与工艺》 2025年第3期361-369,共9页
分子筛的晶体尺寸和形貌会对催化反应结果产生较大影响。本研究以氢氧化六甲双铵为有机模板剂,通过在初始凝胶中加入金属阳离子的策略调节OFF分子筛形貌,成功合成了c-OFF(六棱柱)、Mg-OFF(纺锤体)、Li-OFF(针棒状)、Rb-OFF(板状)、Cs-O... 分子筛的晶体尺寸和形貌会对催化反应结果产生较大影响。本研究以氢氧化六甲双铵为有机模板剂,通过在初始凝胶中加入金属阳离子的策略调节OFF分子筛形貌,成功合成了c-OFF(六棱柱)、Mg-OFF(纺锤体)、Li-OFF(针棒状)、Rb-OFF(板状)、Cs-OFF(墩状)、Zr-OFF(椭球体)分子筛,并采用X射线衍射(XRD)、扫描电子显微镜(SEM)、N_(2)吸附-脱附和氨气程序升温脱附(NH3-TPD)等表征手段考察了不同金属阳离子对产物的影响。与传统六棱柱c-OFF分子筛(1.0μm×5.0μm)相比,金属阳离子的加入可显著降低晶粒尺寸。以甲醇制烯烃(MTO)为探针反应,对合成的不同形貌OFF分子筛催化性能进行评价,结果表明具有较小长径比的Cs-OFF和Zr-OFF分子筛寿命相对较长,而具有较高长径比的Li-OFF和Rb-OFF分子筛寿命短且副产物C_(5)^(+)增多。 展开更多
关键词 off分子筛 金属阳离子 形貌调控 甲醇制烯烃
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基于lift-off工艺的RF MEMS开关触点平坦化方法
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作者 杨彪 诸葛明华 +1 位作者 吴国才 容炎森 《微纳电子技术》 2025年第2期116-121,共6页
采用表面微加工工艺制备射频微机电系统(RF MEMS)开关,开关触点的平坦化是一项关键工艺,直接影响RF MEMS开关的机械和电学性能。设计静电驱动接触式的RF MEMS开关结构,然后通过在触点上进行套刻制备光刻胶岛、蒸镀制备铝牺牲层,利用lift... 采用表面微加工工艺制备射频微机电系统(RF MEMS)开关,开关触点的平坦化是一项关键工艺,直接影响RF MEMS开关的机械和电学性能。设计静电驱动接触式的RF MEMS开关结构,然后通过在触点上进行套刻制备光刻胶岛、蒸镀制备铝牺牲层,利用lift-off工艺解决触点与牺牲层平坦化的问题。再采用电镀工艺制备金悬臂梁,使用氢氧化钠溶液腐蚀铝释放获得RF MEMS开关。通过原子力显微镜(AFM)、聚焦离子束显微镜(FIB)等仪器对样品进行形貌测量,数据显示开关触点与铝牺牲层的高度差约为27.36 nm,悬臂梁与下方平面的左右空隙差约为22 nm,结果表明通过该方法能够实现开关触点与牺牲层的高度平坦化。 展开更多
关键词 射频微机电系统(RF MEMS)开关 开关触点 牺牲层 平坦化 lift-off工艺
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分离膜的Trade-off效应及其突破研究进展 被引量:1
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作者 杨誉名 贾子钰 杨春维 《应用化工》 CAS CSCD 北大核心 2024年第6期1466-1468,共3页
综述通过文献调研,对膜材料在水通量与污染物截留效率之间存在的此消彼长的Trade-off效应进行分析,并对近几年国内外突破分离膜Trade-off效应的方法进行了总结。结果表明,膜表面接枝两性离子技术、非溶剂诱导相分离技术、结构改性技术... 综述通过文献调研,对膜材料在水通量与污染物截留效率之间存在的此消彼长的Trade-off效应进行分析,并对近几年国内外突破分离膜Trade-off效应的方法进行了总结。结果表明,膜表面接枝两性离子技术、非溶剂诱导相分离技术、结构改性技术、物理共混技术、表面涂覆技术等可以突破该技术瓶颈。而物理共混技术表现出非常优异的效果,且该技术方法相对简便,无需更新设备,易于实施,制备出的膜材料具有良好的机械性能和产水能力。综述为高效分离膜的开发提供了新的技术思路,为膜技术的应用和推广提供有益的技术借鉴。 展开更多
关键词 Trade-off规律 膜材料 表面接枝法 表面涂覆法 掺杂法
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基于drop-off ddPCR方法检测急性髓系白血病C-KIT基因N822位点突变及其临床应用
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作者 李婷 金晔 +7 位作者 袁倩 姚冬明 向鹤麟 肖高飞 于迪 冷加燕 林江 钱军 《江苏大学学报(医学版)》 CAS 2024年第2期151-155,160,共6页
目的:建立急性髓系白血病(acute myeloid leukemia, AML)患者C-KIT基因N822位点突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)定量检测方法,并评价其临床应用价值。方法:针对C-KIT基因第17外显子设计一对引物及探针,优化drop... 目的:建立急性髓系白血病(acute myeloid leukemia, AML)患者C-KIT基因N822位点突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)定量检测方法,并评价其临床应用价值。方法:针对C-KIT基因第17外显子设计一对引物及探针,优化drop-off ddPCR反应条件及体系,评价该方法的特异性、灵敏度、重复性,使用所建立的方法对140例已行Sanger测序的AML初诊患者骨髓标本进行检测,并用二代测序(next generation sequencing, NGS)验证结果;用drop-off ddPCR对3例阳性患者化疗后C-KIT突变频率进行动态监测。结果:drop-off ddPCR检测C-KIT基因N822位点突变的最适退火温度为54℃,空白检测限为1.62拷贝数/μL,最低检测下限为10.12拷贝数/μL,线性良好。140例AML初诊患者样本中Sanger测序检出2例阳性(1.4%),而ddPCR共检出突变7例(5.0%),突变频率为0.29%~7.41%;进一步应用常规NGS方法对ddPCR阳性样本进行验证,共检出阳性3例(2.1%),等位基因频率为1.26%~8.00%。动态监测3例阳性患者C-KIT突变频率,结果显示治疗达完全缓解时C-KIT突变频率明显下降甚至降低至0。结论:本研究建立了检测C-KIT基因N822位点突变的drop-off ddPCR技术,具有良好的方法学检测性能,其灵敏度高于Sanger测序和NGS,有望用于阳性患者缓解后的可检测残留疾病监测及治疗指导。 展开更多
关键词 drop-off微滴式数字PCR C-KIT基因 基因突变 微小残留病 急性髓系白血病 预后
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人工法off-line HDF对血液透析充分性和高同型半胱氨酸血症的影响
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作者 吴飞飞 罗来敏 +2 位作者 范燕娜 张桂玲 龚燕燕 《实用临床医学(江西)》 CAS 2024年第4期19-22,27,共5页
目的探究人工法off-line HDF对维持性血液透析(MHD)患者透析充分性、高同型半胱氨酸血症(HHcy)的影响。方法随机选取2021至2023年于南昌大学第一附属高新医院血液透析中心稳定透析6个月以上的MHD患者30例,进行单中心自身对照研究,时长6... 目的探究人工法off-line HDF对维持性血液透析(MHD)患者透析充分性、高同型半胱氨酸血症(HHcy)的影响。方法随机选取2021至2023年于南昌大学第一附属高新医院血液透析中心稳定透析6个月以上的MHD患者30例,进行单中心自身对照研究,时长6个月。前3个月维持每周2次高通量血液透析(HFHD)联合1次on-line HDF,后3个月维持每周2次人工法off-line HDF联合1次on-line HDF。于研究第3个月、第6个月时用全自动生化分析仪检测透析前后血尿素氮(BUN)、血肌酐(SCr)、β2-微球蛋白(β2MG)、同型半胱氨酸(Hcy)、白蛋白(Alb)、C反应蛋白(CRP)、血红蛋白(Hb)、甲状旁腺素(iPTH)、磷(P)、钾(K)水平;计算血清尿素清除指数(Kt/V)、尿素下降率(URR)和β2MG清除率。结果人工法off-line HDF模式透析的Kt/V、URR及β2MG清除率均较显著高于HFHD模式透析(P<0.05);人工法off-lineHDF模式透析Kt/V、URR及β2MG清除率达到透析充分的百分率分别为83.33%、83.33%和93.33%,均显著高于HFHD模式透析(P<0.05)。与HFHD模式透析时相比,人工法off-lineHDF模式透析结束后,患者透析前Hcy水平降低,Alb水平升高(P<0.05)。结论人工法off-line HDF模式透析可显著增加Kt/V、URR和β2MG清除率,提高MHD患者的透析充分性达标率,且对HHcy具有改善作用。 展开更多
关键词 人工法off-line HDF 血液透析 透析充分性 高同型半胱氨酸血症 血液透析滤过
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基于ease-off的弧齿锥齿轮齿面高阶接触分析方法
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作者 陈鹏 王三民 李飞 《航空动力学报》 EI CAS CSCD 北大核心 2024年第6期238-247,共10页
为应对弧齿锥齿轮二阶接触分析方法的不足与其高阶接触理论实现的复杂问题,基于ease-off拓扑曲面方程与弧齿锥齿轮齿面方程的结合以及传动误差与接触迹线和ease-off之间的解析关系,提出以传动比高阶导数和接触迹线短程曲率为高阶接触参... 为应对弧齿锥齿轮二阶接触分析方法的不足与其高阶接触理论实现的复杂问题,基于ease-off拓扑曲面方程与弧齿锥齿轮齿面方程的结合以及传动误差与接触迹线和ease-off之间的解析关系,提出以传动比高阶导数和接触迹线短程曲率为高阶接触参数的离散齿面的高阶接触分析方法,并建立基于有限差分的简便计算方法。结果表明,高阶齿面的传动比高阶导数波动值分别为0.0031、0.0019与0.001,数值反映齿面形貌的全局特性;接触线短程曲率波动值分别为0.0000769、0.000586和0.000127,说明沿接触迹线的齿面接触过程的复杂性。结果不仅验证了离散齿面高阶接触分析方法的正确性与有效性,而且说明该方法降低了高阶接触参数的计算难度,为齿面全局设计提供了可能。 展开更多
关键词 弧齿锥齿轮 ease-off 高阶接触分析 有限差分法 全局接触问题
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Validation of the TOPAS Monte-Carlo Code of the Off-Field Dose of a 6 MV Synergy Linac
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作者 Kodjo Joel Fabrice N’Guessan Ibrahima Sakho Bogbé D. L. H. Gogon 《Journal of Biosciences and Medicines》 2024年第7期38-54,共17页
The risk of radiation-induced second cancer and the late tissue loss due to Off-field doses in radiotherapy remain a serious concern. Monte Carlo (MC) simulation is currently one of the most accurate methods for calcu... The risk of radiation-induced second cancer and the late tissue loss due to Off-field doses in radiotherapy remain a serious concern. Monte Carlo (MC) simulation is currently one of the most accurate methods for calculating these doses. MC simulation model based on the Particle Simulation Tool (TOPAS) has been developed to simulate the off-field dose of an Elekta Synergy linear accelerator (Linac) emitting 6 MV photons. Measurements were taken in a water phantom using an ionization chamber to validate this model. The Percentage Depth Dose (PDD) at the depth of 0.0, 5.0, 10.0 and 15.0 cm from the beam axis for a 10 × 10 cm2 field size was measured and simulated. Off-field dose profiles at the depth of 1.5 (dmax), 5.0 and 10.0 cm for field sizes of 5 × 5, 10 × 10, 15 × 15, and 20 × 20 cm2 respectively were measured and simulated. Comparison of measured and simulated off-field dose values showed a good agreement. The average gamma passing rate of the PDDs and profiles curves for off-field doses were 87.5% and 98.11% respectively. The local dose difference based on the PDD curve between the measured and simulated was less than 6.0 % for all locations. For all field size considered in this study, the average difference between profile curves for off-field dose measured and simulated was 9.1%. PDDs and Profiles curves for off-field dose simulation uncertainties were less than 2.0% and 1.0% respectively. TOPAS-MC simulation model developed is a good representation of our 6 MV Linac Elekta Synergy for assessing off-field dose, which would be the primary cause of some secondary cancers. 展开更多
关键词 Radiotherapy off-Field Dose Secondary Cancer TOPAS-MC Simulation DOSIMETRY
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Basic Research on the Burden of Dropping off and Picking up Children: Differences by Employment Type and Gender in the Tokyo Metropolitan Area
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作者 Jun Morio Koshi Isono +1 位作者 Masahiko Kikuchi Tetsuo Morita 《Journal of Transportation Technologies》 2024年第3期445-461,共17页
There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences i... There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences in child drop-off and pick-up by employment type and gender, utilizing the “Metropolitan Area Person Trip Survey,” which is a statistical data set. The study targeted households in which both spouses were between 30 and 49 years old, had children under the age of 6, and included the following three groups. 1) Dual-income Group 1 (both spouses employed/on contract/temporary);2) Dual-income Group 2 (husband employed/on contract/temporary, wife part-time);3) Full-time housewife group (husband employed, wife unemployed). The analysis revealed that a) wives are almost always responsible for dropping off and picking up their children;b) husbands drop off and pick up their children less frequently in dual-income households;and c) households with children raising within 10 to 30 km of Tokyo Station have longer commuting times and need to reduce the burden of dropping off and picking up their children. 展开更多
关键词 Drop-off and Pick-Up Employment Type GENDER Dual-Income Households Tokyo Metropolitan Area
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Preoperative Serum Albumin Levels and Postoperative Acute Kidney Injury in Off-Pump Coronary Artery Bypass Surgery: A Single-Center Study in Bangladesh
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作者 Ahmad Pear Salahuddin Md. Abir Tazim Chowdhury +6 位作者 Munama Magdum Dewan Iftakher Reza Chowdhury Nittya Nanda Pal Md. Nahedul Morshed Md. Zafar-Al-Nimari Latifa Nasrin Farooque Ahmed 《World Journal of Cardiovascular Surgery》 2024年第8期131-144,共14页
Background: Serum albumin, a vital plasma protein, helps maintain intravascular colloidal osmotic pressure, cardiac output, and renal function. Low preoperative serum albumin is linked to poor outcomes, including acut... Background: Serum albumin, a vital plasma protein, helps maintain intravascular colloidal osmotic pressure, cardiac output, and renal function. Low preoperative serum albumin is linked to poor outcomes, including acute kidney injury (AKI), after off-pump coronary artery bypass (OPCAB) surgery. This study aimed to assess the relationship between preoperative serum albumin levels and early postoperative renal injury. Methods: This prospective comparative cross-sectional study was conducted from August 2019 to February 2021 at the National Heart Foundation Hospital & Research Institute, Bangladesh. It included 160 adult patients with normal preoperative renal function undergoing OPCAB. Patients were divided into two groups: Group A (serum albumin ≥ 4.0 gm/dl) and Group B (serum albumin Results: Preoperative serum albumin was significantly different between groups (Group A: 4.21 ± 0.05 gm/dl, Group B: 3.69 ± 0.04 gm/dl, p = 0.028). Group B had a higher incidence of hypertension (71.25% vs. 51.25%, p st and 3rd postoperative days were higher in Group B (p th day. Postoperative AKI occurred in 18.75% of Group A and 36.25% of Group B. Multivariate regression indicated that low preoperative serum albumin is an independent risk factor for postoperative AKI (p = 0.012, OR = 1.815, CI: 0.675 - 1.162). Conclusion: Preoperative serum albumin level is a valuable predictor of postoperative renal function. Ensuring high normal serum albumin levels before surgery can help minimize the risk of postoperative AKI. 展开更多
关键词 Serum Albumin Acute Kidney Injury (AKI) off-Pump Coronary Artery Bypass Surgery BANGLADESH
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Off-Pump Coronary Artery Bypass Grafting in Patients with Left Ventricular Dysfunction: Short-Term Results from a Single Center in Bangladesh
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作者 Muhit Abdullah Md. Abir Tazim Chowdhury +9 位作者 Satyajit Sharma Rehana Akther Munama Magdum Munjerin Refat Synthee Md. Zafar-Al-Nimari Saikat Das Gupta Saleh Ahmed Samir Kumar Biswas M. Quamrul Islam Talukder Farooque Ahmed 《World Journal of Cardiovascular Surgery》 2024年第9期145-156,共12页
Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-... Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-term outcomes and functional improvements in LVD patients post-OPCAB. Methods: The study included 200 coronary artery disease patients who underwent isolated off-pump coronary artery bypass grafting (OPCAB) at the National Heart Foundation Hospital and Research Institute between January 2019 and June 2020. Patients were categorized into Group 1, with a left ventricular ejection fraction (LVEF) of 30% - 39%, and Group 2, with an LVEF of 40% or higher. Echocardiographic assessments of left ventricular dimensions and ejection fraction were performed preoperatively, at discharge, and one month postoperatively. Results: In Group 1, preoperative left ventricular internal dimensions during diastole (LVIDd) and systole (LVIDs) were 53.48 ± 4.40 mm and 44.23 ± 3.93 mm, respectively, with a left ventricular ejection fraction (LVEF) of 35.28% ± 2.26%. At discharge, these values improved to 51.58 ± 4.04 mm (LVIDd), 41.23 ± 5.30 mm (LVIDs), and 39.25% ± 3.75% (LVEF). One month postoperatively, further improvements were observed: 46.29 ± 3.76 mm (LVIDd), 37.45 ± 3.68 mm (LVIDs), and 43.22% ± 4.67% (LVEF). Group 2 showed similar positive outcomes, with preoperative values of 47.09 ± 5.06 mm (LVIDd), 35.11 ± 5.25 mm (LVIDs), and 50.13% ± 7.25% (LVEF), improving to 42.37 ± 4.18 mm (LVIDd), 31.05 ± 4.19 mm (LVIDs), and 55.33% ± 7.05% (LVEF) at one month postoperatively. Both groups demonstrated significant improvements in left ventricular function and NYHA class, with most patients moving from class III/IV to I/II. Complications were minimal, and no mortality was observed. Conclusion: OPCAB is safe and effective for patients with LVEF 30% - 39% and LVEF ≥ 40%, providing significant short-term functional improvements without increased risk. 展开更多
关键词 off-Pump Coronary Artery Bypass Grafting Left Ventricular Dysfunction (LVD) Short-Term Outcomes
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Trade-Offs and Synergie Effects of Regulating Ecosystem Services along an Climatic Gradient in Slovakia
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作者 Jarmila Makovníková Stanislav Kološta Boris Pálka 《Journal of Geoscience and Environment Protection》 2024年第6期135-150,共16页
This study aims to assess the synergies and trade-offs of regulating ecosystem services. Ecosystem services are non-linearly interconnected and changes in one service can positively or negatively affect another. We ev... This study aims to assess the synergies and trade-offs of regulating ecosystem services. Ecosystem services are non-linearly interconnected and changes in one service can positively or negatively affect another. We evaluated ecosystem services based on biophysical indicators using an expert scoring system that determines the corresponding soil functions and is part of the existing databases available in Slovakia. This methodological combination enabled us to provide unique mapping and assessment of ecosystem services within Slovakia. Correlation analysis between individual regulating ecosystem services and climate regions, slope, texture, and altitude confirm the statistically significant influence of climate and slope in all agricultural land, arable land, and grassland ecosystems. Statistically significant synergistic effects were established between the regulation of the water regime and the regulation of soil erosion within each climate region, apart from the very warm climate region. Only in a very warm climate region was potential of regulating ecosystem services mutually beneficial for soil erosion control and soil cleaning potential (immobilization of inorganic pollutants). 展开更多
关键词 Agroecosystem Services Climatic Zone MAPPING Trade-offs SYNERGIES
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Efficient Vision Transformers for Autonomous Off-Road Perception Systems
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作者 Max H. Faykus III Adam Pickeral +2 位作者 Ethan Marquez Melissa C. Smith Jon C. Calhoun 《Journal of Computer and Communications》 2024年第9期188-207,共20页
The development of autonomous vehicles has become one of the greatest research endeavors in recent years. These vehicles rely on many complex systems working in tandem to make decisions. For practical use and safety r... The development of autonomous vehicles has become one of the greatest research endeavors in recent years. These vehicles rely on many complex systems working in tandem to make decisions. For practical use and safety reasons, these systems must not only be accurate, but also quickly detect changes in the surrounding environment. In autonomous vehicle research, the environment perception system is one of the key components of development. Environment perception systems allow the vehicle to understand its surroundings. This is done by using cameras, light detection and ranging (LiDAR), with other sensor systems and modalities. Deep learning computer vision algorithms have been shown to be the strongest tool for translating camera data into accurate and safe traversability decisions regarding the environment surrounding a vehicle. In order for a vehicle to safely traverse an area in real time, these computer vision algorithms must be accurate and have low latency. While much research has studied autonomous driving for traversing well-structured urban environments, limited research exists evaluating perception system improvements in off-road settings. This research aims to investigate the adaptability of several existing deep-learning architectures for semantic segmentation in off-road environments. Previous studies of two Convolutional Neural Network (CNN) architectures are included for comparison with new evaluation of Vision Transformer (ViT) architectures for semantic segmentation. Our results demonstrate viability of ViT architectures for off-road perception systems, having a strong segmentation accuracy, lower inference speed and memory footprint compared to previous results with CNN architectures. 展开更多
关键词 Semantic Segmentation off-Road Vision TRANSFORMERS CNNS Autonomous Driving
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Effect of Spray Rails on Takeoff Performance of Amphibian Aircraft
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作者 Soham S. Bahulekar Alberto W. Mello 《World Journal of Engineering and Technology》 2024年第1期117-140,共24页
Amphibian aircraft have seen a rise in popularity in the recreational and utility sectors due to their ability to take off and land on both land and water, thus serving a myriad of purposes, such as aerobatics, survei... Amphibian aircraft have seen a rise in popularity in the recreational and utility sectors due to their ability to take off and land on both land and water, thus serving a myriad of purposes, such as aerobatics, surveillance, and firefighting. Such seaplanes must be aerodynamically and hydrodynamically efficient, particularly during the takeoff phase. Naval architects have long employed innovative techniques to optimize the performance of marine vessels, including incorporating spray rails on hulls. This research paper is dedicated to a comprehensive investigation into the potential utilization of spray rails to enhance the takeoff performance of amphibian aircraft. Several spray rail configurations obtained from naval research were simulated on a bare Seamax M22 amphibian hull to observe an approximate 10% - 25% decrease in water resistance at high speeds alongside a 3% reduction in the takeoff time. This study serves as a motivation to improve the design of the reference airplane hull and a platform for detailed investigations in the future to improve modern amphibian design. 展开更多
关键词 Seaplane Spray Rails Hull Optimization Take-off Performance
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1例新的Penta D基因座off-ladder等位基因测序分析
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作者 刘双爱 张晓燕 +3 位作者 娄季武 赵颖 曹泰华 严提珍 《中国优生与遗传杂志》 2024年第3期545-549,共5页
目的鉴定1例新的PentaD基因座短串联重复序列(STR)分型标准外(OL)等位基因的序列构成。方法用AGCU Expressmarker 22荧光检测试剂盒和华夏TM白金PCR扩增试剂盒对一对父女进行STR分型。用Chelex-100法提取DNA,进行PentaD基因座的PCR扩增... 目的鉴定1例新的PentaD基因座短串联重复序列(STR)分型标准外(OL)等位基因的序列构成。方法用AGCU Expressmarker 22荧光检测试剂盒和华夏TM白金PCR扩增试剂盒对一对父女进行STR分型。用Chelex-100法提取DNA,进行PentaD基因座的PCR扩增,纯化回收PCR扩增片段后进行测序。结果AGCU Expressmarker 22荧光检测试剂盒检出Penta D基因座为单峰,相邻的D10S1248基因座检出三等位基因;华夏^(TM)白金PCR扩增试剂盒检出PentaD和D10S1248基因座为双等位基因,PentaD基因座检出OL等位基因;测序结果显示该OL等位基因核心序列为[AAAGA]_(20)AAAA,是一个新的微变异等位基因。根据法医学STR基因座命名规范,将该等位基因命名为20.4。结论对于STR分型中出现的微变异等位基因或OL等位基因可进行测序鉴定,对于OL等位基因的精确分型将丰富STRBase数据库,对提高基因座个体识别和亲权鉴定能力具有重要意义。 展开更多
关键词 短串联重复序列 分型标准外等位基因 Penta D DNA测序
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基于MODIS数据的Landsat-7 SLC-off影像修复方法研究 被引量:18
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作者 朱长明 沈占锋 +3 位作者 骆剑承 杨辽 胡晓东 沈金祥 《测绘学报》 EI CSCD 北大核心 2010年第3期251-256,共6页
研究如何修复由于扫描行校正器SLC故障而造成的数据坏行,成为国际遥感研究的热点。文章在总结现有的修复方法基础上提出用相同时相的MODIS09数据修复SLC-off数据的方法。该方法采用时空自适应反射率融合模型(STARFM)算法实现MODIS09数据... 研究如何修复由于扫描行校正器SLC故障而造成的数据坏行,成为国际遥感研究的热点。文章在总结现有的修复方法基础上提出用相同时相的MODIS09数据修复SLC-off数据的方法。该方法采用时空自适应反射率融合模型(STARFM)算法实现MODIS09数据和TM/ETM+数据的融合,获得与SLC-off数据相同时相和空间分辨率的融合数据,然后采用局部线性直方图匹配完成对SLC-off数据填充。实验证明该方法修复效果明显好于传统方法,解决了传统修复方法中存在的一些问题,一定程度上提高了ETM+SLC-off数据的利用率。 展开更多
关键词 SLC-off 缝隙数据 修复 MODIS ETM+
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带通配符和One-Off条件的序列模式挖掘 被引量:23
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作者 吴信东 谢飞 +2 位作者 黄咏明 胡学钢 高隽 《软件学报》 EI CSCD 北大核心 2013年第8期1804-1815,共12页
很多应用领域产生大量的序列数据.如何从这些序列数据中挖掘具有重要价值的模式,已成为序列模式挖掘研究的主要任务.研究这样一个问题:给定序列S、支持度阈值和间隔约束,从序列S中挖掘所有出现次数不小于给定支持度阈值的频繁序列模式,... 很多应用领域产生大量的序列数据.如何从这些序列数据中挖掘具有重要价值的模式,已成为序列模式挖掘研究的主要任务.研究这样一个问题:给定序列S、支持度阈值和间隔约束,从序列S中挖掘所有出现次数不小于给定支持度阈值的频繁序列模式,并且要求模式中任意两个相邻元素在序列中的出现位置满足用户定义的间隔约束.设计了一种有效的带有通配符的模式挖掘算法One-Off Mining,模式在序列中的出现满足One-Off条件,即模式的任意两次出现都不共享序列中同一位置的字符.在生物DNA序列上的实验结果表明,One-Off Mining比相关的序列模式挖掘算法具有更好的时间性能和完备性. 展开更多
关键词 数据挖掘 序列模式挖掘 频繁模式 通配符 One-off条件
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弹药的热烤(Cook-off)实验 被引量:19
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作者 张蕊 冯长根 陈朗 《火工品》 CAS CSCD 北大核心 2002年第4期37-39,共3页
热烤试验(Cook-off test)是评估武器弹药热安全性的一个重要的实验。本文介绍了Cook-off的定义和Cook-off实验的发展过程、实验方法,对国内外Cook-off实验研究现状和发展方向进行了分析和展望。。
关键词 Cook-off 含能材料 热安全性 武器弹药 热烤试验
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RDX炸药热烤(Cook-off)实验及数值模拟 被引量:21
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作者 冯长根 张蕊 陈朗 《含能材料》 EI CAS CSCD 2004年第4期193-198,共6页
对一种改性的RDX炸药进行了热烤实验。应用热传导理论对实验中炸药的热作用过程进行了分析,并通过软件PHOENICS3.3对RDX在热烤过程中的热响应情况进行了模拟。结果表明,在环境温度较低时,RDX受热发生分解,所放出的热量可以及时地散失到... 对一种改性的RDX炸药进行了热烤实验。应用热传导理论对实验中炸药的热作用过程进行了分析,并通过软件PHOENICS3.3对RDX在热烤过程中的热响应情况进行了模拟。结果表明,在环境温度较低时,RDX受热发生分解,所放出的热量可以及时地散失到环境中,从而不发生爆炸。环境温度较高时,药柱的边沿受热形成局部高温,导致热点火,使药剂发生爆炸。 展开更多
关键词 爆炸力学 热点火 数值模拟 Cook—off实验 RDX炸药
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