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永磁同步电动机电磁振动特性及抑制措施
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作者 李永枭 成豪杰 +2 位作者 唐旭 马兆兴 王瑞华 《科学技术与工程》 北大核心 2024年第17期7148-7158,共11页
电磁振动水平是永磁同步电动机的重要评价指标之一,为了有效抑制永磁同步电动机的电磁振动,首先建立了转子永磁体磁动势、定子绕组电流磁动势与定子齿槽相互作用产生的径向电磁力的解析分析模型。然后建立了电机的变参数矢量控制系统的... 电磁振动水平是永磁同步电动机的重要评价指标之一,为了有效抑制永磁同步电动机的电磁振动,首先建立了转子永磁体磁动势、定子绕组电流磁动势与定子齿槽相互作用产生的径向电磁力的解析分析模型。然后建立了电机的变参数矢量控制系统的场路耦合联合分析模型,以一台11 kW内置式永磁同步电动机为样机,利用机械阻抗法得到了电机主要低阶电磁力产生的电磁振动噪声频谱,确定了对电机电磁振动起主要作用的低阶电磁力的频率。最后利用遗传-蚁群算法,研究了通过优化电机的定子齿槽参数有效削弱具有上述频率的低阶电磁力,从而有效抑制电机的电磁振动。结果显示,利用所提方法确定的定子齿槽参数能有效抑制电机的电磁振动,并且对电机的运行性能产生的影响较小。 展开更多
关键词 永磁同步电动机 电磁振动 解析分析 遗传-蚁群算法 抑制措施
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一种苯酚降解菌Pseudoxanthomonas sp. BF-6的分离鉴定及其降解特性及途径研究 被引量:3
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作者 卫晓博 侯颖 +3 位作者 程豪杰 秦翠丽 牛明福 徐建强 《生物技术通报》 CAS CSCD 北大核心 2021年第10期72-80,共9页
苯酚是最常见的有机污染物,为了获得降解苯酚的细菌,并探究其降解苯酚的特性和途径,采用连续富集和稀释平板分离,从农药厂活性污泥中得到一株能以苯酚作为唯一碳源生长的菌株BF-6,通过16S rRNA序列分析和生理生化试验将该菌株鉴定为假... 苯酚是最常见的有机污染物,为了获得降解苯酚的细菌,并探究其降解苯酚的特性和途径,采用连续富集和稀释平板分离,从农药厂活性污泥中得到一株能以苯酚作为唯一碳源生长的菌株BF-6,通过16S rRNA序列分析和生理生化试验将该菌株鉴定为假黄单胞菌(Pseudoxanthomonas sp.)。单因素试验结果表明,菌株BF-6在温度为20-37℃和pH5.0-10.0范围内均可很好的降解苯酚;在此条件下,5%接种量的菌株BF-6在36 h内可将100 mg/L苯酚降解97.79%,96 h可将200 mg/L苯酚降解97.58%。经苯酚诱导后,菌株BF-6细胞粗酶液表现出苯酚羟化酶和邻苯二酚1,2-双加氧酶活性,表明菌株BF-6降解苯酚的途径为邻位途径。本研究为低浓度苯酚的微生物降解提供了新的菌种资源。 展开更多
关键词 苯酚 假黄单胞菌 分离鉴定 降解特性 降解途径
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基于CRISPR/Cas9系统构建FOXA2表达示踪体系
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作者 程浩杰 张振旺 +3 位作者 谭桂湘 刘昱翔 卜会铜 谭拥军 《生物技术通报》 CAS CSCD 北大核心 2018年第5期80-86,共7页
利用CRISPR/Cas9系统在基因FOXA2蛋白质编码区后插入绿色荧光蛋白核酸序列,实现对FOXA2基因开启和关闭的示踪。通过靶向序列选择、Cas9靶向质粒及Donor片段的克隆、细胞转染并进行流式细胞荧光分选、阳性细胞有限稀释、富集培养及单克... 利用CRISPR/Cas9系统在基因FOXA2蛋白质编码区后插入绿色荧光蛋白核酸序列,实现对FOXA2基因开启和关闭的示踪。通过靶向序列选择、Cas9靶向质粒及Donor片段的克隆、细胞转染并进行流式细胞荧光分选、阳性细胞有限稀释、富集培养及单克隆细胞的鉴定和转录翻译水平验证等5个方面,进行实验研究。在编辑的乳腺肿瘤细胞MCF-7中,绿色荧光蛋白有效表达;乳腺癌细胞内绿色荧光蛋白的表达水平同FOXA2蛋白的表达水平正相关,且经肿瘤细胞上皮间质转化进程诱导因子EGF的诱导,绿色荧光蛋白和FOXA2表达水平同步降低。方法学上CRISPR/Cas9靶向FOXA2并利用细胞内同源性定向修复插入绿色荧光蛋白序列成功;利用报告基因蛋白表达水平示踪目的基因的开启、关闭及表达量高低结果准确、方法简单,效果明显。 展开更多
关键词 CRISPR/Cas9 基因编辑 FOXA2 示踪 乳腺癌 MCF-7 上皮间质转化
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β-Glucan Improves Protective Qi Status in Adults with Protective Qi Deficiency——A Randomized,Placebo-Controlled,and Double-Blinded Trial 被引量:2
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作者 WU Jun-rong cheng hao-jie +9 位作者 SHI Jian-pin YIN Wei-dong WANG Jun OU Xuan-qiao CHEN Jin-li Ira Bernstein Mark Levy Rolando Maddela Robert Sinnott TIAN Jun-qiang 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2022年第5期394-402,共9页
Objective:To test the hypothesis thatβ-glucan enhances protective qi(PQi),an important Chinese medicine(CM)concept which stipulates that a protective force circulates throughout the body surface and works as the firs... Objective:To test the hypothesis thatβ-glucan enhances protective qi(PQi),an important Chinese medicine(CM)concept which stipulates that a protective force circulates throughout the body surface and works as the first line of defense against"external pernicious influences".Methods:A total of 138 participants with PQi deficiency(PQD)were randomized to receiveβ-glucan(200 mg daily)or placebo for 12 weeks.Participants’PQi status was assessed every 2 weeks via conventional diagnosis and a standardized protocol from which a PQD severity and risk score was derived.Indices of participants’immune and general health status were also monitored,including upper respiratory tract infection(URTI),saliva secretory Ig A(s Ig A),and self-reported measures of physical and mental health(PROMIS).Results:PQi status was not significantly different between theβ-glucan and placebo treatment groups at baseline but improved significantly in theβ-glucan(vs.placebo)group in a time-dependent manner.The intergroup differences[95%confidence interval(CI)]in severity score(scale:1-5),risk score(scale:0-1),and proportion of PQD participants(%)at finish line was 0.49(0.35-0.62),0.48(0.35-0.61),and 0.36(0.25-0.47),respectively.Additionally,β-glucan improved URTI symptom(scale:1-9)and PROMIS physical(scale:16.2-67.7)and mental(scale:21.2-67.6)scores by a magnitude(95%CI)of 1.0(0.21-1.86),5.7(2.33-9.07),and 3.0(-0.37-6.37),respectively,over placebo.Conclusions:β-Glucan ameliorates PQi in PQD individuals.By using stringent evidence-based methodologies,our study demonstrated that Western medicine-derived remedies,such asβ-glucan,can be employed to advance CM therapeutics.(Clinical Trial.Gov registry:NCT03782974) 展开更多
关键词 Β-GLUCAN Chinese medicine protective qi protective qi deficiency
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Proof-of-Concept and Feasibility Study to Evaluate the Effect of β-Glucan on Protective Qi Deficiency in Adults
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作者 Mark Levy WU Jun-rong +5 位作者 SHI Jian-pin cheng hao-jie QU Xuan-qiao Ira Bernstein Robert Sinnott TIAN Jun-qiang 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2021年第9期666-673,共8页
Objective:To preliminarily explore the potential effect ofβ-glucan on Chinese medicine(CM)concept protective qi deficiency(PQD),and the methodology for future definitive studies.Methods:To have a standardized assessm... Objective:To preliminarily explore the potential effect ofβ-glucan on Chinese medicine(CM)concept protective qi deficiency(PQD),and the methodology for future definitive studies.Methods:To have a standardized assessment of PQD,a list of 13 potentially PQD-relevant parameters were firstly created,each with defined quantitative or categorial scales.Using the data from 37 participants with(21 cases)or without(16 cases)PQD,multivariate logistic modeling was conducted to create a preliminary diagnostic PQD risk score.Subsequently,21 participants diagnosed with PQD were treated withβ-glucan in a dose of 200 mg/day for 8 weeks.Data were collected for trial acceptability measures(rate of recruitment,withdrawal,and compliance),and the participants were assessed for PQD status at baseline and every 2 weeks thereafter.Results:The preliminary logistic model consisted of 3 parameters(low voice and apathy,aversion to wind and cold,and Cun pulse).The resulting risk score demonstrated a degree of PQD-predicting accuracy that,as evaluated by statistical(discrimination and classification)methods,was higher than those obtained from any of the individual candidate parameters.The 21 PQD participants treated withβ-glucan demonstrated good receptibility and a time-dependent improvement in PQD status as evidenced by the decrease of PQD participant to 9.5%at the end of study.Conclusions:This study demonstrated the effect of proof-of-concept ofβ-glucan on improving PQD and the proof-of-concept of a multivariate-model-derived diagnostic PQD risk score.It also indicated feasibility for future definitive studies.Studies like this embody an innovative approach that uses therapies derived from the mainstream biomedicine to enrich therapeutics guided by CM principle.(Trial registration No.NCT03829228). 展开更多
关键词 Β-GLUCAN protective qi deficiency Chinese medicine diagnostic risk score
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