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Pre/Post Assessments Analysis in Training Electro-Technical Seafarers Experts
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作者 E. A. Karagianni E. P. Apostolopoulou +4 位作者 I. M. Prousalidis I. K. Gyparis A. D. Tsigopoulos C. N. Vazouras Ai. E. Tsiakla 《Journal of Shipping and Ocean Engineering》 2019年第1期14-29,共16页
In maritime industry, personnel’s training is considered by shipping companies as a top priority matter on the list of factors affecting competitiveness in operating vessels. This paper presents the importance and th... In maritime industry, personnel’s training is considered by shipping companies as a top priority matter on the list of factors affecting competitiveness in operating vessels. This paper presents the importance and the effects of training Electro-Technical Experts in the context of latest developments, particularly the advent of the “Electric Ship” and the “Communicative Ship” analyzing the feedback received from several relevant two-days seminars for “Ship Electrical and Electronic Systems for Electro-Technical Officers”, in North East European countries. The pre-test and post-test self assessment method that has been used for more efficient interaction between trainers and trainees is analyzed using t-statistics. The attendees have had diverse basic backgrounds, yet company experts Fleet Engineers on merchant or war ships. The training’s effectiveness and gain is discussed in this paper and further proposals for the Electrical and Electronic training are presented through the valuable feedback for improvement. 展开更多
关键词 Electro-technical officers maritime education and TRAINING pre/post testing SELF-ASSESSMENT standards of TRAINING certification and watch keeping t-test TRAINING experts
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Adsorption of 17β-estradiol from aqueous solution by raw and direct/pre/post-KOH treated lotus seedpod biochar 被引量:7
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作者 Ni Liu Yunguo Liu +7 位作者 Guangming Zeng Jilai Gong Xiaofei Tan Jun Wen Shaobo Liu Luhua Jiang Meifang Li Zhihong Yin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第1期10-23,共14页
Five biochars derived from lotus seedpod(LSP)were applied to examine and compare the adsorption capacity of 17β-estradiol(E2)from aqueous solution.The effect of KOH activation and the order of activation steps on mat... Five biochars derived from lotus seedpod(LSP)were applied to examine and compare the adsorption capacity of 17β-estradiol(E2)from aqueous solution.The effect of KOH activation and the order of activation steps on material properties were discussed.The effect of contact time,initial concentration,p H,ionic strength and humic acid on E2 adsorption were investigated in a batch adsorption process.Experimental results demonstrated that the pseudo second-order model fitted the experimental data best and that adsorption equilibrium was reached within 20 hr.The efficiency of E2 removal increased with increasing E2 concentration and decreased with the increase of ionic strength.E2 adsorption on LSP-derived biochar(BCs)was influenced little by humic acid,and slightly affected by the solution p H when its value ranged from 4.0 to 9.0,but considerably affected at p H 10.0.Low environmental temperature is favorable for E2 adsorption.Chemisorption,π–πinteractions,monolayer adsorption and electrostatic interaction are the possible adsorption mechanisms.Comparative studies indicated that KOH activation and the order of activation steps had significant impacts on the material.Post-treated biochar exhibited better adsorption capacity for E2 than direct treated,pretreated,and raw LSP biochar.Pyrolyzed biochar at higher temperature improved E2 removal.The excellent performance of BCs in removing E2 suggested that BCs have potential in E2 treatment and that the biochar directly treated by KOH would be a good choice for the treatment of E2 in aqueous solution,with its advantages of good efficiency and simple technology. 展开更多
关键词 17Β-ESTRADIOL Lotus seedpod derived biochar Activation order pre-or post-treatment ADSORPTION
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一种应用于MRC pre/post-rake的抗抽头串扰算法
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作者 张航 吕明 《电子科技》 2007年第5期33-37,共5页
新兴的Pre/post-rake技术和传统rake接收机技术相比,在提高了输出信噪比的同时,也引入了更强的抽头串扰,并且该串扰在普遍的情况下将严重制约pre/post-rake的性能。为了有效地消除抽头串扰对接收性能的影响,文中提出了应用于pre/post... 新兴的Pre/post-rake技术和传统rake接收机技术相比,在提高了输出信噪比的同时,也引入了更强的抽头串扰,并且该串扰在普遍的情况下将严重制约pre/post-rake的性能。为了有效地消除抽头串扰对接收性能的影响,文中提出了应用于pre/post-rake技术的抗抽头串扰算法,将该算法和MRC pre/post-rake技术相结合,通过理论计算和通过MATLAB仿真。在不影响其它性能的同时,使MRC pre/post-rake获得了更好的抗抽头串扰能力,从而提高了pre/post-rake的接收性能。 展开更多
关键词 抽头串扰 抗抽头串扰算法 MRC pre/post—rake 相关矩阵
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Comparison of pre-treatment and post-treatment use of selenium in retinal ischemia reperfusion injury 被引量:4
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作者 Alper Yazici Hasan Aksit +6 位作者 Esin Sogutlu Sari Arzu Yay Haydar Ali Erken Dilek Aksit Harun Cakmak Kamil Seyrek Sitki Samet Ermis 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第2期263-268,共6页
AIM: To investigate the effects of selenium in rat retinal ischemia reperfusion(IR) model and compare pretreatment and post-treatment use.METHODS: Selenium pre-treatment group(n =8) was treated with intraperitoneal(i.... AIM: To investigate the effects of selenium in rat retinal ischemia reperfusion(IR) model and compare pretreatment and post-treatment use.METHODS: Selenium pre-treatment group(n =8) was treated with intraperitoneal(i.p.) selenium 0.5 mg/kg for7 d and terminated 24 h after the IR injury. Selenium posttreatment group( n = 8) was treated with i. p. selenium0.5 mg/kg for 7d after the IR injury with termination at the end of the 7d period. Sham group(n =8) received i.p.saline injections identical to the selenium volume for 7d with termination 24 h after the IR injury. Control group(n =8) received no intervention. Main outcome measures were retina superoxide dismutase(SOD), glutathione(GSH),total antioxidant status(TAS), malondialdehyde(MDA),DNA fragmentation levels, and immunohistological apoptosis evaluation.RESULTS: Compared to the Sham group, selenium pre-treatment had a statistical difference in all parameters except SOD. Post-treatment selenium also resulted in statistical differences in all parameters except the MDA levels. When comparing selenium groups, the pre-treatment selenium group had a statistically higher success in reduction of markers of cell damage such as MDA and DNA fragmentation. In contrast, the post-selenium treatment group had resulted in statisticallyhigher levels of GSH. Histologically both selenium groups succeeded to limit retinal thickening and apoptosis. Pre-treatment use was statistically more successful in decreasing apoptosis in ganglion cell layer compared to post-treatment use.CONCLUSION: Selenium was successful in retinal protection in IR injuries. Pre-treatment efficacy was superior in terms of prevention of tissue damage and apoptosis. 展开更多
关键词 RETINA SELENIUM ISCHEMIA-REPERFUSION APOPTOSIS pre-treatment post-TREATMENT oxidative stress
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Control of Glyphosate-Resistant Giant Ragweed (<i>Ambrosia trifida</i>L.) with 2,4-D Followed by Pre-Emergence or Post-Emergence Herbicides in Glyphosate-Resistant Soybean (<i>Glycine max</i>L.) 被引量:1
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作者 Amit J. Jhala Lowell D. Sandell Greg R. Kruger 《American Journal of Plant Sciences》 2014年第15期2289-2297,共9页
Control of glyphosate-resistant giant ragweed is a challenge, particularly for soybean growers, because of limited effective post-emergence (POST) herbicide options. Many soybean growers in no-till production systems ... Control of glyphosate-resistant giant ragweed is a challenge, particularly for soybean growers, because of limited effective post-emergence (POST) herbicide options. Many soybean growers in no-till production systems use 2,4-D in burndown application for control of broadleaf weeds, including giant ragweed. Field experiments were conducted at David City, NE, in 2012 and 2013 to evaluate 2,4-D followed by PRE or POST herbicide programs for control of glyphosate-resistant giant ragweed in glyphosate-resistant soybean. Results suggested that burndown application of 2,4-D or saflufenacil plus imazethapyr resulted in 89 to 99% control of giant ragweed at 21 days after treatment. Burndown-only treatments of S-metolachlor plus metribuzin or sulfentrazone plus cloransulam resulted in poor control (≤65%) of giant ragweed and reduced soybean yield (≤ 577 kg&middotha-1). Burndown application of 2,4-D followed by saflufenacil plus imazethapyr, S-metolachlor plus metribuzin, or sulfentrazone plus cloransulam applied pre-emergence (PRE) or cloransulam, chlorimuron, fomesafen, imazethapyr, or lactofen in tank-mixtures with acetochlor applied POST resulted in 87% to 99% giant ragweed control, reduced density to ≤7 plants m-2, and resulted in soybean yield from 2519 to 3823 kg&middotha-1. There was no difference among and between 2,4-D followed by PRE or POST herbicides for giant ragweed control, density, or soybean yield, indicating all the two pass herbicide programs were effective. It is concluded that glyphosate-resistant giant ragweed can be effectively controlled in soybean by including 2,4-D in burndown program followed by PRE or POST herbicides tested in this study. 展开更多
关键词 Corn Burndown GIANT RAGWEED Biomass post-EMERGENCE pre-Emergence Resistance Management
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Weed Control with Halosulfuron Applied Preplant Incorporated, Preemergence or Postemergence in White Bean 被引量:4
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作者 Nader Soltani Robert E. Nurse +1 位作者 Christy Shropshire Peter H. Sikkema 《Agricultural Sciences》 2014年第10期875-881,共7页
Four field trials were conducted over a three-year period (2011-2013) at various locations in Ontario to evaluate the level of weed control provided by halosulfuron applied PPI,PREor POST at 17.5, 35 and 70 g&midd... Four field trials were conducted over a three-year period (2011-2013) at various locations in Ontario to evaluate the level of weed control provided by halosulfuron applied PPI,PREor POST at 17.5, 35 and 70 g&middotai&middotha-1 in white bean. Halosulfuron applied PPI or PRE at 17.5, 35 and 35 g&middotai&middotha-1 caused 2% or less visible injury 1 and 4 WAA in white bean. However, halosulfuron applied POST at 17.5, 35 and 70 g&middotai&middotha-1 caused 2% - 8% and 1% - 3% white bean injury at 1 and 4 WAA, respectively. There was no decrease in white bean seed yield relative to the weed free check due to weed interference with halosulfuron applied PPI or PRE at doses evaluated, except when applied PRE at 17.5 g&middotai&middotha-1 which resulted in a decrease in seed yield of 25%. Weed interference caused a decrease in white bean yield of 47%, 42% and 44%, when halosulfuron was applied POST at 17.5, 35 and 70 g&middotai&middotha-1, respectively. Halosulfuron applied PPI, PRE and POST controlled AMARE 92% - 100%, 85% - 99% and 47% - 75%;CHEAL 95% - 100%, 83% - 99% and 36% - 51%;and SINAR 97% - 100%, 99% - 100% and 100%, respectively. Halosulfuron applied PPI and PRE reduced AMARE density 93% - 97% and 75% - 95%;CHEAL density 89% - 98% and 81% - 93%;and SINAR density 99% - 100% and 99% - 100%, respectively. Halosulfuron applied PPI and PRE reduced dry weight of AMARE 96% - 98% and 86% - 96%;CHEAL 96% - 98% and 87% - 93%;and SINAR 100% and 100%, respectively. Halosulfuron applied POST at rates evaluated reduced SINAR density and dry weight 100% but caused no significant reduction in AMARE and CHEAL density or dry weight compared to the weedy check. Based on these results, halosulfuron applied PPI orPREat 35 g&middotai&middotha-1 can be used safely for the control of selected broadleaf weeds in white bean production. 展开更多
关键词 Efficacy Dry BEAN PHASEOLUS VULGARIS preEMERGENCE (pre) preplant-Incorporated (PPI) postEMERGENCE (post) Sensitivity Tolerance
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Pre-and post-selected measurements with coupling-strength-dependent modulation
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作者 Zhaoxue Li Jiangdong Qiu +5 位作者 Linguo Xie Lan Luo Xiong Liu Zhiyou Zhang Changliang Ren JingLei Du 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第3期135-140,共6页
Pre-and post-selected(PPS) measurement, especially the weak PPS measurement, has been proved to be a useful tool for measuring extremely tiny physical parameters. However, it is difficult to retain both the attainable... Pre-and post-selected(PPS) measurement, especially the weak PPS measurement, has been proved to be a useful tool for measuring extremely tiny physical parameters. However, it is difficult to retain both the attainable highest measurement sensitivity and precision with the increase of the parameter to be measured. Here, a modulated PPS measurement scheme based on coupling-strength-dependent modulation is presented with the highest sensitivity and precision retained for an arbitrary coupling strength. This idea is demonstrated by comparing the modulated PPS measurement scheme with the standard PPS measurement scheme in the case of unbalanced input meter. By using the Fisher information metric, we derive the optimal pre-and post-selected states, as well as the optimal coupling-strength-dependent modulation without any restriction on the coupling strength. We also give the specific strategy of performing the modulated PPS measurement scheme, which may promote practical application of this scheme in precision metrology. 展开更多
关键词 modulated pre-and post-selected MEASUREMENTS FISHER information metric unbalanced input METER
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What Is the Difference between Post- and Pre-Dilution in On-Line Haemodiafiltration in the Removing of Median-Molecular-Weight Toxins?
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作者 Konstantinos S. Mavromatidis Irini M. Kalogiannidou Ploumis S. Passadakis 《Journal of Biosciences and Medicines》 CAS 2023年第3期105-119,共15页
Introduction: β<sub>2</sub>-microglobulin and prolactin are medium-molecular-weight toxins. We believe that the rate of removal of these molecules, using filters with two different surfaces, in post- and ... Introduction: β<sub>2</sub>-microglobulin and prolactin are medium-molecular-weight toxins. We believe that the rate of removal of these molecules, using filters with two different surfaces, in post- and pre-dilution haemodiafiltration, will be of interest to the literature. Methods: We studied, in 12 haemodialyzed patients, the removal of those, with filter with surface of 2.5 m<sup>2</sup> (Group A) or 2.1 m<sup>2</sup> (Group B) with post-dilution haemodiafiltration, and with a filter with surface 2.5 m<sup>2</sup> with pre-dilution (Group C). Results: Satisfactory removal of β<sub>2</sub>-microglobulin (best with post-dilution) was found, and a good rate of removal of prolactin without the filter surface played a role in both cases. Conclusion: The elimination of β<sub>2</sub>-microglobulin in post-dilution is not affected by the filter surface area. Pre-dilution achieves removal of β<sub>2</sub>-microglobulin, less than that of post-dilution. Prolactin was removed satisfactorily regardless of the filter surface in post-dilution, and its removal appears to be less than that of β<sub>2</sub>-microglobulin. 展开更多
关键词 HAEMODIAFILTRATION pre-Dilution post-Dilution β2-Microglobulin Prolactin
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Effects of Fillerwire Composition along with Different Pre- and Post-Heat Treatment on Mechanical Properties of AISI 4130 Welded by the GTAW Process
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作者 Ali Emamian Ardalan Emamian Amir Hossein Kowkabi 《Materials Sciences and Applications》 2010年第3期135-140,共6页
This research intends to find out the optimal mechanical properties of AISI 4130 steel welded by the GTAW process. Six test plates were joined by two types of filler wire with similar chemical composition to the base ... This research intends to find out the optimal mechanical properties of AISI 4130 steel welded by the GTAW process. Six test plates were joined by two types of filler wire with similar chemical composition to the base metal, and with lower carbon content and slightly higher alloy elements content compared to the first one. Test plates then exerted three different pre-heat and post-heat treatments on both groups. The three types of heat treatments were alternatively without pre-heat and post-heat, with pre-heat only, and finally with pre-heat and post-heat. Tensile, side bends and impact tests (for weld zone and HAZ) have been conducted. Results show that using low-carbon filler wire along with pre- and post-heat resulted in outstanding mechanical properties. 展开更多
关键词 HAZ (Heat Affected Zone) Filler Wire pre- and post-heat Treatments GTAW PROCESS
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天津市部分新诊断HIV阳性男男性行为者PrEP和nPEP知晓及使用情况分析 被引量:1
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作者 费丽萍 赵鹤鹤 +6 位作者 王实 郭燕 龚卉 于茂河 杨杰 汤后林 吕繁 《中国艾滋病性病》 北大核心 2025年第3期283-287,共5页
目的了解新诊断HIV阳性MSM对PrEP和nPEP的知晓和使用情况。方法以2023年12月至2024年8月天津市部分新诊断HIV阳性MSM为研究对象,通过问卷调查收集研究对象的基本人口学信息、性行为特征及PrEP、nPEP的知晓和使用情况。使用Logistic回归... 目的了解新诊断HIV阳性MSM对PrEP和nPEP的知晓和使用情况。方法以2023年12月至2024年8月天津市部分新诊断HIV阳性MSM为研究对象,通过问卷调查收集研究对象的基本人口学信息、性行为特征及PrEP、nPEP的知晓和使用情况。使用Logistic回归分析新诊断HIV阳性MSM中PrEP和nPEP知晓的影响因素。结果共计纳入研究对象251人,其中83人(33.1%)知晓PrEP,111人(55.8%)知晓nPEP。12人(4.8%)曾使用过PrEP,9人(3.6%)曾使用过nPEP。多因素Logistic回归分析显示,大专及以上文化程度者(PrEP:aOR=3.31,95%CI:1.66~6.83;nPEP:aOR=2.33,95%CI:1.28~4.28)、性伴数≥2(PrEP:aOR=2.29,95%CI:1.14~4.69;nPEP:aOR=2.02,95%CI:1.12~3.68)、既往有HIV检测史(PrEP:aOR=12.26,95%CI:5.62~30.00;nPEP:aOR=3.99,95%CI:2.21~7.36)是PrEP和nPEP知晓的促进因素。此外,同性性向(aOR=2.52,95%CI:1.08~6.31)也是nPEP知晓的促进因素。结论天津市部分新诊断HIV阳性MSM的PrEP和nPEP的知晓和使用情况均较低。可以通过网络平台、社会组织及同伴教育者在动员MSM进行HIV检测的同时普及PrEP和nPEP知识。 展开更多
关键词 艾滋病病毒感染者 暴露前预防 非职业暴露后预防 知晓 男男性行为者
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Correlation Study of Neurotransmitter and Immune Levels in Pre-Hospital Emergency Nurses with Post-Traumatic Stress Disorder
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作者 Yanling Zhou Min Guo +1 位作者 Xiangling Jiang Long Li 《Journal of Behavioral and Brain Science》 2024年第1期12-22,共11页
Objective: To investigate the occurrence of PTSD in pre-hospital emergency nurses and its related factors, and to compare the differences of neurotransmitter and immune-related factors between pre-hospital emergency n... Objective: To investigate the occurrence of PTSD in pre-hospital emergency nurses and its related factors, and to compare the differences of neurotransmitter and immune-related factors between pre-hospital emergency nurses who experienced traumatic events and those who did not develop PTSD and healthy people. How: Post-traumatic Stress Disorder Self-Rating Scale (PCL-C) tests were performed on pre-hospital emergency nurses in PTSD group, non-PTSD group and healthy control group, and the plasma monoamine neurotransmitters and serum cytokines were determined by double-antibody sandwich ABC-ELISA assay using enzyme-linked adsorption kit provided by Shanghai Xitang Biotechnology Co., Ltd. Results: 1) There were statistically significant differences in PCL-C scores between PTSD group, non-PTSD group and healthy group (p α between PTSD group, non-PTSD group and healthy group (p Conclusion: Pre-hospital emergency nurses should have early psychological intervention and guidance to reduce the occurrence of PTSD in emergency and emergency nurses. 展开更多
关键词 pre-Hospital First Aid NURSE post-Traumatic Stress Disorder NEUROIMMUNOLOGY
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基于护理助手App的BOPPPS教学模式在新入职护士规范化培训中的应用
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作者 王瑞方 郭珂清 +5 位作者 杜章楠 冯珊珊 孙艳丽 郭军芳 魏华 丁敬艳 《河南医学研究》 2026年第1期183-188,共6页
目的探讨基于护理助手App的导学互动的加式教育(BOPPPS)教学模式在新入职护士规范化培训中的应用效果。方法前瞻性以濮阳市安阳地区医院2023年9月新入职规范化培训护士86名为研究对象,采用抓取随机球法分为对照组和试验组,各43名。对照... 目的探讨基于护理助手App的导学互动的加式教育(BOPPPS)教学模式在新入职护士规范化培训中的应用效果。方法前瞻性以濮阳市安阳地区医院2023年9月新入职规范化培训护士86名为研究对象,采用抓取随机球法分为对照组和试验组,各43名。对照组采用传统教学模式,试验组采用基于护理助手App的BOPPPS教学模式。比较两组新入职护士规培出科考试成绩、护士临床实践能力评价量表、护理人员自主学习能力评价量表、临床护理带教老师行为评价量表、教学效果满意度量表评分。结果试验组新入职护士的基础知识、案例分析及总成绩分别为(50.46±4.35)分、(33.10±3.68)分、(84.32±8.26)分,高于对照组的(47.30±5.12)分、(29.54±3.05)分、(77.18±6.44)分,差异有统计学意义(P<0.05);试验组新入职护士的临床实践能力中核心制度、岗位职责、工作能力、疾病护理、技术操作、常用化验检查结果解读、常用药物相关知识、护理文书、应急能力评分分别为(7.68±1.26)分、(8.12±0.92)分、(8.30±0.86)分、(8.03±0.94)分、(7.89±1.36)分、(8.21±0.87)分、(7.65±1.14)分、(7.42±1.35)分、(7.58±1.29)分,高于对照组的(6.95±1.35)分、(7.02±1.35)分、(6.58±1.33)分、(6.45±1.29)分、(6.54±1.02)分、(7.38±1.12)分、(6.98±1.02)分、(6.59±1.10)分、(6.87±1.13)分,差异有统计学意义(P<0.05),劳动纪律评分为(6.34±1.36)分与(6.02±1.52)分比较,差异无统计学意义(P>0.05);试验组新入职护士的自主学习能力中自我动机信念、自我监控与调节、任务分析、自我评价及总分分别为(58.45±4.36)分、(38.98±5.02)分、(22.36±3.75)分、(15.24±2.20)分、(133.87±12.58)分,高于对照组的(50.62±5.48)分、(34.25±4.76)分、(16.84±3.02)分、(12.45±2.14)分、(113.50±10.46)分,差异有统计学意义(P<0.05);试验组临床护理带教老师行为中教学技巧、与学生的关系、知识与技能、个性及总分分别为(103.64±5.29)分、(52.87±4.55)分、(43.15±3.18)分、(48.62±4.24)分、(247.18±21.60)分,高于对照组的(90.48±6.45)分、(45.52±4.86)分、(38.74±3.20)分、(44.59±5.84)分、(215.72±20.53)分,差异有统计学意义(P<0.05);试验组新入职护士的教育效果满意度(97.67%)高于对照组(81.40%),差异有统计学意义(P<0.05)。结论基于护理助手App的BOPPPS教学模式有利于提升临床带教老师行为能力,提高新入职护士的综合素质及教学满意度。 展开更多
关键词 导学互动的加式教育 手机 教学 护士 规范化培训
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病毒膜融合蛋白构象转变机制与稳定策略
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作者 解宸一 董翔歌 +5 位作者 战久宇 朱洪伟 于馨 刘洋 于佳玉 张兴晓 《生物化学与生物物理进展》 北大核心 2026年第1期5-18,共14页
病毒膜融合蛋白通过从预融合构象转变成融合后构象,介导病毒与宿主细胞膜融合,并进一步使病毒的核酸转移到细胞内部。其预融合构象是疫苗设计和抗病毒药物开发的理想靶标构象。研究这类蛋白质的构象转变机制及如何稳定其预融合构象,一... 病毒膜融合蛋白通过从预融合构象转变成融合后构象,介导病毒与宿主细胞膜融合,并进一步使病毒的核酸转移到细胞内部。其预融合构象是疫苗设计和抗病毒药物开发的理想靶标构象。研究这类蛋白质的构象转变机制及如何稳定其预融合构象,一直是具有挑战性的课题。本文总结了三类膜融合蛋白在结构和功能上的差异:Ⅰ类蛋白质以α螺旋为主,形成三聚体,依赖受体结合或低pH触发融合肽释放;Ⅱ类蛋白质(如登革病毒E蛋白)以β折叠为主,二聚体向三聚体重排,融合环由低pH激活;Ⅲ类蛋白质(如单纯疱疹病毒糖蛋白B)融合α螺旋和β折叠,机制涉及内部融合环插入和膜重塑。并通过深入理解病毒的膜融合机制,介绍了几种目前能够有效地稳定病毒膜融合蛋白预融合构象的方法,包括二硫键连接稳定结构域间相互作用、疏水空腔填充增强疏水核心稳定性、脯氨酸限制铰链区域的结构转变、多聚体结构域稳定三聚体构象。本文所总结讨论的稳定化策略已经在多种病毒膜融合蛋白的研究中得到验证,并进一步应用于疫苗抗原设计。另外,本文介绍时间分辨冷冻电镜等新型技术在捕捉构象中间态和解析动态转变过程中的应用潜力。本文为开发稳定的病毒膜融合蛋白提供了理论参考,为理解病毒膜融合机制和下一代疫苗和抗病毒药物的开发提供了重要基础。 展开更多
关键词 病毒膜融合蛋白 膜融合机制 预融合构象 融合后构象 构象稳定性
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幻听访谈指引单联合应对卡在精神分裂症伴幻听症状病人中的应用
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作者 王秀霞 巢丽红 《全科护理》 2026年第1期19-23,共5页
目的:观察幻听访谈指引单联合应对卡在精神分裂症伴幻听症状病人中的应用效果。方法:选取江苏省某三级甲等精神专科医院精神科2023年10月—2024年10月诊断为精神分裂症且伴有幻听症状的94例病人作为研究对象,按照入院时间顺序分为对照... 目的:观察幻听访谈指引单联合应对卡在精神分裂症伴幻听症状病人中的应用效果。方法:选取江苏省某三级甲等精神专科医院精神科2023年10月—2024年10月诊断为精神分裂症且伴有幻听症状的94例病人作为研究对象,按照入院时间顺序分为对照组和观察组,将2023年10月—2024年3月收治的46例病人作为对照组,将2024年4月—10月收治的48例病人作为观察组。对照组给予常规护理,观察组在常规护理的基础上采用幻听访谈指引单联合应对卡进行护理干预,观察两组病人住院期间因幻听导致的保护性约束发生率、病人对护理满意度以及幻听风险得分。结果:观察组病人住院期间因幻听导致的保护性约束发生率为18.75%,低于对照组的36.96%(P<0.05);观察组约束病人约束时长为(9.8±3.9)h,明显短于对照组的(19.6±4.2)h(P<0.05);观察组病人对护士专业知识能力和健康宣教能力满意度均高于对照组(P<0.05);观察组病人出院时幻听风险得分为(16.13±3.14)分,明显低于对照组的(18.26±3.26)分(P<0.05)。结论:幻听访谈指引单联合应对卡应用于精神分裂症伴幻听症状病人中,可提高病人的护理满意度,降低保护性约束发生率和幻听风险,同时缩短约束时长。 展开更多
关键词 精神分裂症 幻听症状 幻听访谈指引单 应对卡 约束率 幻听应对 满意度 前-后对照研究
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微波非热效应——半个世纪的科学探索
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作者 黄卡玛 陈文琦 《电子科技大学学报》 北大核心 2026年第1期27-39,共13页
系统梳理了微波非热效应领域五十年的探索历程,从概念定义、实验证据、理论争议到未来方向展开全面的综述。回顾实验层面(活化能/指前因子测定、等温对照、原位测温)与理论层面(相干电振荡、自由基对/三重态机制、膜噪声限制等)的主要... 系统梳理了微波非热效应领域五十年的探索历程,从概念定义、实验证据、理论争议到未来方向展开全面的综述。回顾实验层面(活化能/指前因子测定、等温对照、原位测温)与理论层面(相干电振荡、自由基对/三重态机制、膜噪声限制等)的主要成果与分歧,重点提出并扩展了“后极化效应”理论假说——通过分子动力学模拟和量子力学计算证实弱微波场能改变极性分子碰撞模式与能量分布。同时,还指出该领域面临的争议,如理论普适性不足、热效应难以完全排除等挑战。认为争议的症结在于:尚无单一理论能覆盖所有现象、量子力学与热力学的基本约束不可违背、实验上难以完全排除热路径。一旦非热效应被明确证实,它将对多个领域产生深远影响。 展开更多
关键词 微波非热效应 活化能 指前因子 相干电振荡 自由基对 三重态 膜噪声限制 后极化效应
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前/后稀释血液透析滤过与中截留膜透析尿毒症毒素清除的比较
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作者 徐卓佳 程丹 王栋栋 《中国血液净化》 2026年第1期11-15,共5页
目的比较前/后稀释血液透析滤过(Pre-/Post-hemodiafiltration,Pre-/Post-HDF)与中截留膜透析(medium cut-off hemodialysis,MCO-HD)对小分子、中分子和较大中分子毒素的清除情况。方法选取2024年3月—10月在民航总医院血液透析中心维... 目的比较前/后稀释血液透析滤过(Pre-/Post-hemodiafiltration,Pre-/Post-HDF)与中截留膜透析(medium cut-off hemodialysis,MCO-HD)对小分子、中分子和较大中分子毒素的清除情况。方法选取2024年3月—10月在民航总医院血液透析中心维持性血液透析的患者为研究对象,给予Pre-HDF、Post-HDF及MCO-HD治疗。比较3种治疗方式血清尿素下降率(urea reduction rate,URR)、β_(2)-微球蛋白(β_(2)-mocroglobuine,β_(2)-MG)、α1-微球蛋白(α1-mocroglobuine,α1-MG)下降率,比较透析废液中β_(2)-MG、α1-MG和白蛋白(album,ALB)的总清除量。结果共纳入22例患者,3种治疗方式URR比较:MCO-HD组高于Pre-HDF组(q=13.151,P<0.001)和Post-HDF组(q=19.063,P<0.001)。Post-HDF组β_(2)-MG下降率高于MCO-HD组(q=4.753,P=0.005)和Pre-HDF组(q=11.022,P<0.001)。MCO-HD组α1-MG下降率高于Pre-HDF组(q=11.647,P<0.001)和Post-HDF组(q=7.642,P<0.001)。透析废液中β_(2)-MG的总去除量比较:Pre-HDF组低于Post-HDF组(q=5.691,P=0.002)和MCO-HD组(q=7.058,P<0.001),Post-HDF组和MCO-HD组间比较无统计学差异(q=3.252,P=0.083)。透析废液中α1-MG的总去除量比较:MCO-HD组高于Pre-HDF组(q=22.218,P<0.001)和Post-HDF组(q=12.286,P<0.001)。透析废液中ALB的总去除量比较:MCO-HD组高于Pre-HDF组(q=10.831,P<0.001)和Post-HDF组(q=5.345,P=0.004)。结论MCO-HD与Pre-/Post-HDF相比,在去除较大中分子物质方面更有优势,但与Pre-/Post-HDF相比,MCO-HD模式下的ALB损失更明显。 展开更多
关键词 前稀释-血液透析滤过 后稀释-血液透析滤过 中截留透析
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重庆市男男性行为者HIV PrEP和nPEP用药使用意愿及相关因素 被引量:1
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作者 江梓梏 李龙 +2 位作者 欧阳琳 吴国辉 谭天宇 《中国艾滋病性病》 CSCD 北大核心 2024年第12期1278-1282,共5页
目的 分析重庆市MSM对HIV PrEP和nPEP的使用意愿及相关因素,为制定针对该人群的HIV PrEP和nPEP服务策略提供科学依据。方法 通过“滚雪球”的方法,在重庆市疾病预防控制中心艾滋病自愿咨询门诊招募MSM,通过面对面匿名问卷调查,收集其一... 目的 分析重庆市MSM对HIV PrEP和nPEP的使用意愿及相关因素,为制定针对该人群的HIV PrEP和nPEP服务策略提供科学依据。方法 通过“滚雪球”的方法,在重庆市疾病预防控制中心艾滋病自愿咨询门诊招募MSM,通过面对面匿名问卷调查,收集其一般人口学特征、行为学信息及对PrEP和nPEP使用意愿等相关信息。采用χ^(2)检验和多因素Logistic回归分析对PrEP和nPEP的使用意愿及其相关因素。结果 共调查449名MSM,年龄在18~77岁,平均年龄为(33.5±10.7)岁。57.2%(257人)愿意使用PrEP,66.4%(298人)愿意使用nPEP。多因素Logistic回归分析结果显示,愿意使用nPEP(OR=31.860,95%CI:17.427~58.248)的MSM其PrEP使用意愿相对更高;文化程度是大专以上(OR=1.783,95%CI:1.121~2.836)、性角色是被插入方(OR=2.245,95%CI:1.276~3.952)的MSM其nPEP使用意愿相对更高。结论 重庆市MSM PrEP和nPEP的使用意愿较低,需要根据MSM不同教育程度、性角色针对性开展PrEP和nPEP宣传教育,增强个人风险意识,同时注意PrEP和nPEP联合宣教,提高其使用意愿。 展开更多
关键词 男男性行为者 暴露前预防 非职业暴露后预防 使用意愿
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面向OVT五维解释的三维地震正演模拟应用
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作者 廉西猛 娄凤芹 雷蕾 《物探化探计算技术》 2026年第1期136-144,共9页
地震正演技术在地震解释研究中具有重要的应用价值,在反射特征分析、裂缝预测、储层预测等方面发挥了重要作用。随着勘探技术的进步和勘探目标的日益复杂,在地震解释中使用的地震正演技术逐渐由褶积类向射线类和波动方程类过渡,并且在... 地震正演技术在地震解释研究中具有重要的应用价值,在反射特征分析、裂缝预测、储层预测等方面发挥了重要作用。随着勘探技术的进步和勘探目标的日益复杂,在地震解释中使用的地震正演技术逐渐由褶积类向射线类和波动方程类过渡,并且在应用分析中三维比二维更具优势。但受限于巨大的计算量和较长的模拟周期,三维地震正演模拟技术在解释中的研究成果相对较少。笔者研究讨论了三维波动方程地震正演技术及其并行化方法,提升了应用效率。针对地震正演技术在地震解释研究中的应用方法,笔者提出了面向OVT(偏移距向量片,Offset Vector Tile)五维解释的三维地震正演应用流程,支撑基于全方位和分方位叠加数据的复杂构造响应特征分析工作,本方法可为三维波动方程地震正演技术在地震解释中的应用提供借鉴和指导。 展开更多
关键词 三维正演模拟 地震解释研究 叠后纵横向分析 叠前分方位分析 OVT五维解释
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Case Report: Unusual Complication Post Otoplasty
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作者 Fatima Al Subhi 《Modern Plastic Surgery》 2018年第1期1-7,共7页
Otoplasty is very commonly used for the surgical correction of prominent ears. This procedure generally does not involve major complications. Pain and itching, hematoma and bleeding and infection are the most common c... Otoplasty is very commonly used for the surgical correction of prominent ears. This procedure generally does not involve major complications. Pain and itching, hematoma and bleeding and infection are the most common complications generally observed in post otoplasty patients. We present a case of a 13 years old boy who showed abnormal swelling from the pre- to the post-auricular area throughout the temporal region one day after the surgery. This case is distinct as the swelling was without the involvement of active bleeding but hematoma like complication at the site of surgery. The investigations were undertaken and the probable cause for these unusual observations were most likely related to lymphatic malformation. 展开更多
关键词 OTOPLASTY UNUSUAL COMPLICATION Swelling pre-post AURICULAR Area No Hematoma Lymphatic MALFORMATION
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Differential Expression of miRNAs in Sorghum bicolor under Drought and Salt Stress
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作者 Rania S. El Sanousi Nada B. Hamza +3 位作者 Awadalla A. Abdelmula Ismail A. Mohammed Seif M. Gasim Neeti Sanan-Mishra 《American Journal of Plant Sciences》 2016年第6期870-878,共9页
The regulatory mechanisms of drought and salt-associated miRNAs have not been fully understood in Sorghum bicolor. In this study, we investigated the effect of salinity stress (200 and 300 mM NaCl) and drought stress ... The regulatory mechanisms of drought and salt-associated miRNAs have not been fully understood in Sorghum bicolor. In this study, we investigated the effect of salinity stress (200 and 300 mM NaCl) and drought stress at pre- and post-flowering stages on the expression pattern of small regulatory RNAs in six Sorghum genotypes using semi-quantitative reverse transcriptase PCR (RT-qPCR). The results indicated that both drought and salt stresses altered the expression pattern of miRNAs in a dose-dependent manner. However, each miRNA responded to drought and salt stress in a different pattern among the six sorghum genotypes. miR156, miR167, miR168 and miR399 give different expressions levels compared to other studied miRNAs which may attribute to the adaption of sorghum to drought and salt stress and are good candidates for improving sorghum by transgenic technology. 展开更多
关键词 miRNA UP-REGULATION DOWN-REGULATION pre-FLOWERING post-FLOWERING
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