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Dyslipidemia in Adults with Type 2 Diabetes in a Rural Community in Ganadougou, Mali: A Cross-Sectional Study
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作者 Abdoulaye Diawara Djibril Mamadou Coulibaly +22 位作者 Drissa Kone Mama A. Traore Drissa Konaté Dicko S. Bazi Oumar Kassogue Djeneba Sylla Fatoumata Gniné Fofana Oudou Diabaté Mariam Traore Ibrahim Antoine Nieantao Kaly Keїta Mamadou Diarra Olivia Smith Jian Li Cheickna Cisse Talib Yusuf Abbas Crystal Zheng Segun Fatumo Kassim Traore Mamadou Wele Mahamadou Diakité Seydou O. Doumbia Jeffrey G. Shaffer 《Journal of Diabetes Mellitus》 CAS 2024年第2期133-152,共20页
Dyslipidemia is a disorder where abnormally lipid concentrations circulate in the bloodstream. The disorder is common in type 2 diabetics (T2D) and is linked with T2D comorbidities, particularly cardiovascular disease... Dyslipidemia is a disorder where abnormally lipid concentrations circulate in the bloodstream. The disorder is common in type 2 diabetics (T2D) and is linked with T2D comorbidities, particularly cardiovascular disease. Dyslipidemia in T2D is typically characterized by elevated plasma triglyceride and low high-density lipoprotein cholesterol (HDL-C) levels. There is a significant gap in the literature regarding dyslipidemia in rural parts of Africa, where lipid profiles may not be captured through routine surveillance. This study aimed to characterize the prevalence and demo-graphic profile of dyslipidemia in T2D in the rural community of Ganadougou, Mali. We performed a cross-sectional study of 104 subjects with T2D in Ganadougou between November 2021 and March 2022. Demographic and lipid profiles were collected through cross-sectional surveys and serological analyses. The overall prevalence of dyslipidemia in T2D patients was 87.5% (91/104), which did not differ by sex (P = .368). High low-density lipoprotein cholesterol (LDL-C) was the most common lipid abnormality (78.9%, [82/104]). Dyslipidemia was associated with age and hypertension status (P = .013 and.036, respectively). High total and high LDL-C parameters were significantly associated with hypertension (P = .029 and .006, respectively). In low-resource settings such as rural Mali, there is a critical need to improve infrastructure for routine dyslipidemia screening to guide its prevention and intervention approaches. The high rates of dyslipidemia observed in Gandadougou, consistent with concomitant increases in cardiovascular diseases in Africa suggest that lipid profile assessments should be incorporated into routine medical care for T2D patients in African rural settings. 展开更多
关键词 CHOLESTEROL cross-Sectional Study DYSLIPIDEMIA LIPIDS MALI type 2 Diabetes
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Principle and Experimental Verification of Caudal-fin-type Piezoelectric-stack Pump with Variable-cross-section Oscillating Vibrator 被引量:12
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作者 HU Xiaoqi ZHANG Jianhui +3 位作者 HUANG Yi XIA Qixiao HUANG Weiqing ZHAO Chunsheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第1期128-136,共9页
In the traditional flow-resistance-differential (FRD) type valve-less piezoelectric pump, the generated outflow and pressure are discontinuous because of the inherent periodicity and fluctuation of the pump. To overco... In the traditional flow-resistance-differential (FRD) type valve-less piezoelectric pump, the generated outflow and pressure are discontinuous because of the inherent periodicity and fluctuation of the pump. To overcome these drawbacks, utilizing the bending vibration of piezoelectric bimorph to drive fluid was conducted. However, our investigation on the current status of this piezoelectric bimorph pump shows that larger driving force and vibration amplitude are required for fluid pumping; the pumping can be realized through the centrifugal force; and the mechanism of fluid pumping is no longer further studied. Based on these cases, the paper designed a piezoelectric-stack pump with variable-cross-section oscillating (VCSO) vibrator by imitating the swing of the caudal-fin of tuna, and the pump is neither the rotating type nor the volumetric type according to the taxonomy. The interaction between the oscillating vibrator and the fluid parcel is firstly analyzed from the viewpoint of momentum conservation, and the analytical expression of pump flow rate is obtained. Then the modal and harmonic response analyses on the vibrator immerged in water are carried out. From the analyses the first two orders resonance frequencies are 832 Hz and 1 939 Hz, respectively, and the peak value of the tip amplitude is 0.6 mm. Laser Doppler vibrometer is used to measure both the frequency and vibration amplitude, and the determined first two orders resonance frequencies are 617 Hz and 1 356 Hz, respectively. The measured tip amplitude reaches to the peak value of 0.3 mm. At last, experimental measurement for the flow rates with different driving frequencies is conducted. The results show that the flow rate can reach 560 mL/min at 1 370 Hz when the pump runs under the backpressure of 30 mm water column. And the flow rate is as much as 560% of that of experiment results carried out by researchers from Brazil. The proposed pump innovates in both theory and taxonomy; in addition, the pump overcomes the drawbacks such as large flow fluctuation and low flow rate in the traditional FRD type pumps, which will help to broaden the application of the valve-less piezoelectric pump. 展开更多
关键词 caudal-fin-type variable-cross-section piezoelectric-stack valve-less pump
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Microwave Irradiated Palladium-Catalyzed Cascade Type Cross Coupling of Phenols and Halides for the Synthesis of Polyphenolic Ethers 被引量:1
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作者 Mohammad Al-Masum Houra A. Alalwan 《International Journal of Organic Chemistry》 2020年第4期135-143,共9页
A mild, cascade type methodology was developed for the synthesis of polyphenolic ethers by the palladium-catalyzed cross coupling of phenols and halo compounds under microwave heating. In most cases, reactions run in ... A mild, cascade type methodology was developed for the synthesis of polyphenolic ethers by the palladium-catalyzed cross coupling of phenols and halo compounds under microwave heating. In most cases, reactions run in neat conditions and in some cases, IPA/water mixture, and 1,4-dioxane were employed as solvents to furnish the products. By applying this new method, we were able to synthesize and purify a good number of polyether compounds with complete spectral data. 展开更多
关键词 Polyphenolic Ether cross-Coupling Cascade type Reaction Microwave Heating
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Growth Performance of Different Cross Combinations of Quality Lean Type Pig
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作者 SHEN Xue-lin DUAN Yong-bang 《Animal Husbandry and Feed Science》 CAS 2013年第5期224-226,共3页
Ten healthy weaning piglets of Landrace x Yorkshire (LY) in good body condition with body weight of (24 ± 1.27) kg were selected, and ten weaning piglets of Berkshire × LY (BLY) and Duroc × LY (... Ten healthy weaning piglets of Landrace x Yorkshire (LY) in good body condition with body weight of (24 ± 1.27) kg were selected, and ten weaning piglets of Berkshire × LY (BLY) and Duroc × LY (DLY) with similar situation were also selected respectively to study the growth performance of different cross combinations. Three groups of experimental pigs were bred with conventional diet. The results showed that the average dry matter intakes of combinations of BLY and DLY were slightly decreased by 4.97% and 5.47% compared with the combination of LY, while average daily gain was significantly increased by 3.13% and 1.14%, and feed-weight ratio was decreased by 7.94% and 6.35%, respectively; economic benefit per pig was increased by 0.61 and 0.41 yuan, respectively. The combinations of BLY and DLY have better growth performance, which can be promoted in the production. 展开更多
关键词 Lean type pig cross combinations Growth performance
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苯硼酸参与的Suzuki-Type反应研究进展 被引量:2
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作者 辛炳炜 《榆林学院学报》 2007年第6期49-53,共5页
芳香酮化合物广泛存在于天然产物及药物中间体中,是许多有机化合物的重要结构单元。目前合成芳香酮化合物的方法有多种,其中利用苯硼酸与羧酸衍生物进行Suzuki-Type偶联反应是制备芳香酮化合物的主要手段之一。近年来该类反应受到广泛... 芳香酮化合物广泛存在于天然产物及药物中间体中,是许多有机化合物的重要结构单元。目前合成芳香酮化合物的方法有多种,其中利用苯硼酸与羧酸衍生物进行Suzuki-Type偶联反应是制备芳香酮化合物的主要手段之一。近年来该类反应受到广泛关注并取得了一定进展。就近几年Suzuki-Type反应的研究进展情况进行了综述。 展开更多
关键词 Suzuki—type反应 苯硼酸 酸酐 酰氯 Pd(Ⅱ)络合物
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L-R Crossed积的Maschke定理(英文)
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作者 周小燕 李强 《南京大学学报(数学半年刊)》 CAS 2011年第2期139-148,共10页
本文给出了L-R crossed积的Maschke定理,推广了Blattner和Montgomery给出的crossed积的Maschke定理.
关键词 HOPF代数 L-R crossed积 crossed积 MASCHKE定理
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身体活动水平对2型糖尿病患者颈动脉内膜中层厚度增厚的影响研究
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作者 孙珍珍 崔茜 +4 位作者 楼青青 陈晓栋 方丹 姚平 袁晓丹 《中国全科医学》 CAS 北大核心 2025年第6期697-704,共8页
背景心血管疾病是2型糖尿病(T2DM)患者的主要死亡原因,颈动脉内膜中层厚度(CIMT)增厚可预测心血管疾病的发生。中高水平的身体活动(PA)可改善患者的血糖水平并降低心血管疾病的发生率和死亡风险。探讨这一可改变的生活方式与CIMT的关系... 背景心血管疾病是2型糖尿病(T2DM)患者的主要死亡原因,颈动脉内膜中层厚度(CIMT)增厚可预测心血管疾病的发生。中高水平的身体活动(PA)可改善患者的血糖水平并降低心血管疾病的发生率和死亡风险。探讨这一可改变的生活方式与CIMT的关系可能是预防心血管疾病的有效策略。目的分析不同PA水平与T2DM患者CIMT增厚的关系,为患者推荐个性化活动方案提供科学依据。方法本研究为横断面研究,选取2019年1月—2022年2月于江苏省两家三级甲等医院内分泌门诊就诊的3099例T2DM患者为研究对象,采用国际身体活动量表(IPAQ)短问卷评估患者的PA水平,将患者分为轻度及以下PA组、中度PA组和高强度PA组。通过二元Logistic回归分析探讨PA与CIMT增厚的关系,并按照不同肥胖程度和血压、血脂及糖化达标状况进行分层分析。将PA水平作为连续变量绘制限制性立方样条评价PA与CIMT增厚的剂量反应关系。结果与轻度及以下PA患者(n=981)相比,中度(n=1389)和高强度(n=729)PA患者的年龄较小,糖化血红蛋白(HbA_(1c))和低密度脂蛋白胆固醇(LDL-C)水平较高(P<0.05)。二元Logistic回归分析结果显示,中度PA与发生CIMT增厚的风险呈负关联(OR=0.775,95%CI=0.629~0.956,P<0.05),这种关联独立于社会人口学、生活方式及血脂等生化指标。进一步绘制限制性立方样条结果显示,PA与CIMT增厚的风险之间存在非线性关系(P_(非线性)=0.014)。分层分析结果显示,在体质量正常(n=996)和超重(n=1395)的患者中未发现PA与CIMT的关系(P>0.05);而在肥胖患者(n=708)中仅中度PA与CIMT增厚相关(OR=0.614,95%CI=0.382~0.987,P<0.05);血压、血脂及糖化3项指标均不达标(n=324)和仅1项指标达标(n=1416)的患者,中度PA与发生CIMT增厚呈负相关(P<0.05)。结论PA水平与CIMT增厚存在剂量反应关系,中度PA与CIMT增厚呈负相关,尤其是在肥胖、血压、血脂及糖化控制较差的人群中,而高强度PA对CIMT的影响不显著。 展开更多
关键词 糖尿病 2型 身体活动 颈动脉内膜中膜厚度 横断面研究 江苏省
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Reducing unnecessary crossmatching for hip fracture patients by accounting for preoperative hemoglobin concentration
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作者 Raj M Amin Varun Puvanesarajah +4 位作者 Yash P Chaudhry Matthew J Best Sandesh S Rao Steven M Frank Erik A Hasenboehler 《World Journal of Orthopedics》 2021年第5期292-300,共9页
BACKGROUND Maximum surgical blood order schedules were designed to eliminate unnecessary preoperative crossmatching prior to surgery in order to conserve blood bank resources.Most protocols recommend type and cross of... BACKGROUND Maximum surgical blood order schedules were designed to eliminate unnecessary preoperative crossmatching prior to surgery in order to conserve blood bank resources.Most protocols recommend type and cross of 2 red blood cell(RBC)units for patients undergoing surgery for treatment of hip fracture.Preoperative hemoglobin has been identified as the strongest predictor of inpatient transfusion,but current maximum surgical blood order schedules do not consider preoperative hemoglobin values to determine the number of RBC units to prepare prior to surgery.AIM To determine the preoperative hemoglobin level resulting in the optimal 2:1 crossmatch-to-transfusion(C:T)ratio in hip fracture surgery patients.METHODS In 2015 a patient blood management(PBM)program was implemented at our institution mandating a single unit-per-occurrence transfusion policy and a restrictive transfusion threshold of<7 g/dL hemoglobin in asymptomatic patients and<8 g/dL in those with refractory symptomatic anemia or history of coronary artery disease.We identified all hip fracture patients between 2013 and 2017 and compared the preoperative hemoglobin which would predict a 2:1 C:T ratio in the pre PBM and post PBM cohorts.Prediction profiling and sensitivity analysis were performed with statistical significance set at P<0.05.RESULTS Four hundred and ninety-eight patients who underwent hip fracture surgery between 2013 and 2017 were identified,291 in the post PBM cohort.Transfusion requirements in the post PBM cohort were lower(51%vs 33%,P<0.0001)than in the pre PBM cohort.The mean RBC units transfused per patient was 1.15 in the pre PBM cohort,compared to 0.66 in the post PBM cohort(P<0.001).The 2:1 C:T ratio(inpatient transfusion probability of 50%)was predicted by a preoperative hemoglobin of 12.3 g/dL[area under the curve(AUC)0.78(95%confidence interval(CI),0.72-0.83),Sensitivity 0.66]in the pre PBM cohort and 10.7 g/dL[AUC 0.78(95%CI,0.73-0.83),Sensitivity 0.88]in the post PBM cohort.A 50%probability of requiring>1 RBC unit was predicted by 11.2g/dL[AUC 0.80(95%CI,0.74-0.85),Sensitivity 0.87]in the pre PBM cohort and 8.7g/dL[AUC 0.78(95%CI,0.73-0.83),Sensitivity 0.84]in the post-PBM cohort.CONCLUSION The hip fracture maximum surgical blood order schedule should consider preoperative hemoglobin in determining the number of units to type and cross prior to surgery. 展开更多
关键词 Hip fracture TRANSFUSION Blood conservation HEMOGLOBIN type and cross Maximum surgical blood order schedule
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Study on the Construction of Ecological Drainage Pipe with Critter Crossing Function
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作者 Zhenggen FAN Jiasen PAN +1 位作者 Dengwei DING Jiang YU 《Asian Agricultural Research》 2019年第12期39-41,共3页
Critter passage can to a large extent ensure the safety of living things crossing the road and reduce the traffic mortality of living things arising from crossing the road. Outdoor drainage pipes can eliminate accumul... Critter passage can to a large extent ensure the safety of living things crossing the road and reduce the traffic mortality of living things arising from crossing the road. Outdoor drainage pipes can eliminate accumulated surface water,alleviate the drainage pressure of urban roads,and reduce the phenomenon of urban stagnant water. At present,there are many studies on the construction methods of drainage pipes,and there are also many studies on critter passage,but there is little research on the organic combination of critter passage and drainage pipes. Taking the drainage pipe as the research object,in accordance with the basic requirements of critter passage,this paper studies the construction methods of ecological drainage pipe with critter passage function,in order to solve the problem of single function of drainage pipe at present. It can provide a reference for related research in the future. 展开更多
关键词 Critter crossING ECOLOGICAL type Drainage PIPE CONSTRUCTION
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Pd-Catalyzed Unprecedented Cross-Coupling of Mixed Phenols and Halides for the Synthesis of Aromatic Ethers
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作者 Mohammad Al-Masum Reem M. Albeshy Houra A. Alalwan 《International Journal of Organic Chemistry》 CAS 2022年第2期75-91,共17页
Phenolic compounds present in medicinal and edible plants such as flavonoids, chalcones, coumarins, quinones, and phenolic acids. The antioxidant potential of phenolic compounds shows potent activities for cancer prev... Phenolic compounds present in medicinal and edible plants such as flavonoids, chalcones, coumarins, quinones, and phenolic acids. The antioxidant potential of phenolic compounds shows potent activities for cancer prevention and its treatment. From a green chemistry point of view, cascade (tandem) reactions are ideal techniques in organic synthesis for building complex structures. Cascade techniques are sometimes observed in coupling reactions under mild conditions with a tolerance of multifunctional groups. It will be interesting to find a cascade type reaction to synthesize polyphenolic ethers. This research project achieves a new cross-coupling method for establishing polyphenolic ethers from mixed phenols and halides in the presence of palladium catalyst in moderate to good yields. 展开更多
关键词 Microwave Ethers from Mixed Phenols cross-COUPLING Cascade type Reac-tion
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基于应变增敏的双层十字型FBG触觉感知单元
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作者 孙世政 何江 +2 位作者 秦鸿宇 徐向阳 陈仁祥 《光学精密工程》 EI CAS CSCD 北大核心 2024年第17期2718-2731,共14页
触觉感知是仿生智能感知的重要内容,为了提高光纤布拉格光栅(Fiber Bragg Grating, FBG)触觉感知灵敏度,结合机器手指尖触觉感知需求,提出了一种应变增敏的FBG触觉感知单元。基于应变增敏机理和触觉感知机理分析,设计了一种基于应变增... 触觉感知是仿生智能感知的重要内容,为了提高光纤布拉格光栅(Fiber Bragg Grating, FBG)触觉感知灵敏度,结合机器手指尖触觉感知需求,提出了一种应变增敏的FBG触觉感知单元。基于应变增敏机理和触觉感知机理分析,设计了一种基于应变增敏的双层十字型FBG触觉感知单元,采用刚性球型多点增压结构进行应变增敏。利用仿真分析方法优化了FBG空间分布,并对感知单元进行了静力学和热力学仿真。最后搭建了触觉感知实验平台,结合机器手完成了温度-力触觉协同感知实验。仿真和实验结果表明,FBG1和FBG2的力触觉感知灵敏度分别为18.069 nm/MPa和1.065 nm/MPa,温度感知灵敏度为11.256 pm/℃和11.153 pm/℃。该触觉感知单元有效提高了触觉感知灵敏度,具有良好的线性度和重复性。 展开更多
关键词 光纤传感 光纤布拉格光栅 应变增敏 双层十字型 触觉感知单元
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基于类型矩阵转移的汉越事件因果关系识别
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作者 高盛祥 熊琨 +2 位作者 余正涛 张磊 黄于欣 《重庆邮电大学学报(自然科学版)》 CSCD 北大核心 2024年第1期118-127,共10页
针对汉越跨语言新闻事件因果关系识别中,汉越跨语言的文本语义空间难以统一、新闻之间的因果关联特征捕获困难的问题,提出了基于类型矩阵转移的汉越跨语言新闻事件因果关系识别方法。通过跨语言预训练统一汉越跨语言的文本语义空间,使... 针对汉越跨语言新闻事件因果关系识别中,汉越跨语言的文本语义空间难以统一、新闻之间的因果关联特征捕获困难的问题,提出了基于类型矩阵转移的汉越跨语言新闻事件因果关系识别方法。通过跨语言预训练统一汉越跨语言的文本语义空间,使用树形长短期记忆循环神经网络提取汉越文本中的句法结构化特征,融入汉越句法特征并结合基于事件类型转移的注意力机制,对汉越事件句对的因果关系进行识别。实验结果表明,该方法在汉越跨语言新闻事件因果关系的识别上较基线模型准确率有所提升。 展开更多
关键词 汉越跨语言 事件类型 语言对抗 句法信息 因果关系
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Evaluation of TlOH Effect for Pd<sup>0</sup>-Mediated Cross-Coupling of Methyl Iodide and Excess Boronic Acid Ester toward Fabrication of [<sup>11</sup>C]CH<sub>3</sub>-Incorporated PET Tracer
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作者 Hiroko Koyama Hisashi Doi Masaaki Suzuki 《International Journal of Organic Chemistry》 2013年第3期220-223,共4页
The use of thallium(I) hydroxide (TlOH) as a base is known to extremely accelerate the Suzuki-Miyaura cross-coupling reaction using organoboronic acid or organoboronic acid ester as a substrate. Here, we investigated ... The use of thallium(I) hydroxide (TlOH) as a base is known to extremely accelerate the Suzuki-Miyaura cross-coupling reaction using organoboronic acid or organoboronic acid ester as a substrate. Here, we investigated the effects of TlOH by comparing with other conventional bases such as KOH, K2CO3, and CsF for Pd0-mediated rapid cross-coupling reactions between CH3I and organoborane reagents, such as phenyl-, (Z)-4-benzyloxy-2-butenyl-, and benzylboronic acid pinacol esters under the conditions CH3I/borane/Pd0/base (1:40:1:3) in THF/H2O or DMF/H2O for 5 min with an aim to fabricate a PET tracer efficiently. Consequently, however, the use of TlOH was much less efficient than the other bases for the acceleration of cross-coupling reactions. Thus, it was reconfirmed that the milder and non-toxic conditions using K2CO3 or CsF so far developed by our group were most appropriate for the rapid C-methylations. 展开更多
关键词 Synthesis of Short-Lived POSITRON Emission Tomography Probes Suzuki-Miyaura-type RAPID cross-COUPLING RAPID C-Methylation TlOH
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胀锁型锚索双向加固窄煤柱试验研究与工程应用
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作者 王军 吕顺章 +3 位作者 杨光 王波 谷长宛 王港 《矿业科学学报》 CSCD 北大核心 2024年第2期258-269,共12页
针对沿空掘巷窄煤柱非对称变形问题,提出了对穿锚索双向加固窄煤柱技术,设计了伸长型和胀锁型两种对穿锚索结构及工艺,开展了对穿锚索拉拔试验,试验表明两种锚索结构均满足抗拉要求,从锚索破坏形态、施工便捷性和材料经济性等方面对比分... 针对沿空掘巷窄煤柱非对称变形问题,提出了对穿锚索双向加固窄煤柱技术,设计了伸长型和胀锁型两种对穿锚索结构及工艺,开展了对穿锚索拉拔试验,试验表明两种锚索结构均满足抗拉要求,从锚索破坏形态、施工便捷性和材料经济性等方面对比分析,确定胀锁型对穿锚索为窄煤柱双向加固的首选。进一步通过相似模型试验与数值模拟研究了不同加固方式下煤柱承载变形规律和对穿锚索受力特征。结果表明:双排紧密型对穿锚索加固试件较未加固试件峰值荷载提高了96.04%,且随着锚索排数及数量的增加,窄煤柱双向加固稳定性越来越高,胀锁型对穿锚索提高了煤柱破坏前的能量储存量和临界破坏点。最后,在济宁三号煤矿123_(下)04工作面运输巷开展胀锁式对穿锚索加固窄煤柱工程试验,监测显示对穿锚索锚固力超过220 kN,锚索加固区煤柱帮鼓量降低70%,窄煤柱整体稳定性好,窄煤柱双向加固技术可行,为沿空掘巷工程提供了新技术途径。 展开更多
关键词 沿空掘巷 双向加固 窄煤柱 胀锁型对穿锚索 拉拔试验 承压性能
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深化沈阳现代化都市圈一体化发展的挑战与对策
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作者 邹丽 吴琼 孙楚寒 《中国商论》 2024年第15期155-158,共4页
现代化都市圈一体化发展是城市和国家经济发展到一定阶段的必经之路,本文采用定量和定性分析相结合的方法,深入分析沈阳现代化都市圈一体化发展过程中面临着产业发展阶段存在差异、产业结构趋同、深层次产业分工协作较弱等问题,并根据... 现代化都市圈一体化发展是城市和国家经济发展到一定阶段的必经之路,本文采用定量和定性分析相结合的方法,深入分析沈阳现代化都市圈一体化发展过程中面临着产业发展阶段存在差异、产业结构趋同、深层次产业分工协作较弱等问题,并根据沈阳都市圈7市1区的实际状况,提出构建“1+ 2+ 6”式对策机制,围绕政务一体化、交通一体化和现代化、基础设施一体化、数字资源一体化、产业一体化和互补共生化、公共服务一体化和便利化等方面建立城市跨界发展与互通模式,重塑以沈阳为中心的辽宁经济发展格局,加快辽宁和东北经济发展。 展开更多
关键词 都市圈 一体化发展 “1+2+6”式 城市跨界与互通 高质量发展
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Moderating Effect of Job Type on Job Characteristic Worker Outcome Relationships
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作者 Justina M. Oliveira Charles Scherbaum 《Psychology Research》 2017年第3期164-185,共22页
关键词 调节作用 类型 特性 特征模型 工作满意度 测试工作 JCM 设计
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多连杆式下斜刃横切剪剪切力数值分析
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作者 李东方 周明安 +1 位作者 黄增阳 杨康成 《机械设计与制造》 北大核心 2024年第6期81-85,共5页
针对多连杆式下斜刃横切剪剪切力求解问题,采用有限单元法建立了数值求解模型。用装配后的实物进行了剪切实验,将数值解和实验解、文献解进行对比,三者结果之间比较吻合,验证了数值求解模型合理性。对不同带材厚度h、剪刃侧向间隙Δ、... 针对多连杆式下斜刃横切剪剪切力求解问题,采用有限单元法建立了数值求解模型。用装配后的实物进行了剪切实验,将数值解和实验解、文献解进行对比,三者结果之间比较吻合,验证了数值求解模型合理性。对不同带材厚度h、剪刃侧向间隙Δ、下剪刃斜度tanα、剪切液压缸伸出速度v及上下剪刃磨损量ω下的横切剪剪切力分布规律进行了归纳。分析结果表明,下剪刃磨损对剪切力的分布影响大于上剪刃的磨损,剪切厚度为6mm的带材的最佳剪刃侧向间隙Δ可取为(0.4±0.1)mm、下剪刃斜度tanα可取为1/25、剪切液压缸伸出速度可取为(300±50)mm/s。提出了横切剪在设计、选型、电气调试以及实际使用过程中的一些建议。 展开更多
关键词 下切式斜刃横切剪 剪刃磨损 剪刃侧向间隙 剪切力 数值模拟
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3种构造形式调谐质量阻尼器性能
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作者 吴思远 廖旭钊 +4 位作者 荣坤杰 王俊杰 孔伟明 傅知春 鲁正 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第9期1401-1408,共8页
提出了3种平面内自由运动的调谐质量阻尼器(TMD)构造形式,即十字形(CTMD)、X形(XTMD)和旋风形(TTMD),通过有限元模型对比分析了3种TMD刚度变化、模态和简谐激励振动响应。根据分析结果可知,当TMD激励方向与弹簧垂直时,弹簧出力表现出非... 提出了3种平面内自由运动的调谐质量阻尼器(TMD)构造形式,即十字形(CTMD)、X形(XTMD)和旋风形(TTMD),通过有限元模型对比分析了3种TMD刚度变化、模态和简谐激励振动响应。根据分析结果可知,当TMD激励方向与弹簧垂直时,弹簧出力表现出非线性行为;相比于其他构造形式,TTMD减振效果更为稳定,效率更高。当质量比大于3%时,TTMD抑振效果更为显著。 展开更多
关键词 调谐质量阻尼器 十字形调谐质量阻尼器 X形调谐质量阻尼器 旋风形调谐质量阻尼器 力学行为 动力特性
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基于香菇交配型位点保守区重测序设计引物鉴定单核菌丝交配型的研究
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作者 简文成 邢鑫 +3 位作者 王琪 全建钰 王立安 葛荣朝 《华北农学报》 CSCD 北大核心 2024年第4期87-93,共7页
香菇单核菌丝的杂交受到A和B等2种交配型因子的影响。基于全基因组测序可以对香菇单核菌丝进行交配型鉴定,但存在技术复杂和成本较高的局限。为实现对香菇单核菌丝未知交配型基因的快捷鉴定,以香菇H31和BJ4菌株为材料,采用对交配型位点... 香菇单核菌丝的杂交受到A和B等2种交配型因子的影响。基于全基因组测序可以对香菇单核菌丝进行交配型鉴定,但存在技术复杂和成本较高的局限。为实现对香菇单核菌丝未知交配型基因的快捷鉴定,以香菇H31和BJ4菌株为材料,采用对交配型位点区域的特异性扩增和重测序的方法,确定了可用于未知交配型基因鉴定的PCR扩增引物。利用菌丝杂交结果确定能够杂交的2种单核菌丝,将其交配型分别记为A1B1和A2B2。根据NCBI获得的A和B交配型位点基因序列的比对分析,在其保守区设计引物,对A1B1和A2B2单核菌丝进行PCR扩增。通过对扩增产物的重测序信息进行比对,获得A1和A2、B1和B2不同交配型基因序列中的非保守区,然后在此区域设计4种交配型基因特异性扩增引物,实现对H31和BJ4香菇单核菌丝交配型基因的鉴定。根据分子水平的交配型鉴定结果,对H31和BJ4香菇单核菌丝分别进行杂交验证。结果表明,交配型基因的分子鉴定结果与单核菌丝杂交结果一致。以香菇为试验材料确立的交配型基因鉴定方法不再依赖于全基因组测序,该方法同样适用于其他食用菌交配型基因的鉴定,因此,研究结果对食用菌的遗传育种具有广泛的应用价值。 展开更多
关键词 香菇 杂交育种 交配型鉴定 单核菌丝 引物设计
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两种Rh血型系统抗体导致交叉配血不合原因分析与实验室处理策略
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作者 崔颖 张瑜 +5 位作者 杨世明 许亚莉 齐霞 邢艳 安宁 王宝燕 《细胞与分子免疫学杂志》 CAS CSCD 北大核心 2024年第7期623-628,共6页
目的分析RhDC、RhEc抗原阴性患者血清中存在IgG型抗DC及抗Ec联合抗体的血型血清学特点及临床意义。方法回顾性分析12例血清中存在两种Rh系统不规则抗体的病例的临床资料及实验室检查结果,包括年龄、性别、输血史/妊娠史及血型血清学检... 目的分析RhDC、RhEc抗原阴性患者血清中存在IgG型抗DC及抗Ec联合抗体的血型血清学特点及临床意义。方法回顾性分析12例血清中存在两种Rh系统不规则抗体的病例的临床资料及实验室检查结果,包括年龄、性别、输血史/妊娠史及血型血清学检测结果(ABO、RhD血型鉴定及Rh分型结果、不规则抗体筛选、抗体特异性鉴定、吸收放散试验、抗体效价测定、交叉配血试验)。结果12例患者中,年龄(51.4±16.9)岁。9例有输血史,8例有妊娠史,5例既有输血史又有妊娠史。在血型血清学检测中抗体筛选阳性、交叉配血不合。抗体特异性鉴定及吸收放散试验结果显示,3例患者血清中同时存在IgG型抗D、抗C抗体,抗D效价16~32、抗C效价8~16;9例患者血清中同时存在IgG型抗E、抗c抗体,抗E、抗c效价均为8~16;抗D、抗C联合抗体的患者选择ABO同型RhD阴性,其他Rh抗原为ccee的悬浮红细胞,抗E、抗c联合抗体的患者选择ABO同型RhD阳性,其他Rh抗原为CCee的悬浮红细胞,交叉配血试验结果显示,在盐水、聚凝胺、抗人球蛋白介质中均无凝集、无溶血。结论输血和(或)妊娠免疫是产生两种Rh系统不规则抗体、导致抗体筛选阳性及交叉配血不合的主要原因,ABO同型基础上常规进行Rh配合性输注,对于临床输血的安全性和预防新生儿溶血病的发生具有重要的价值和意义。 展开更多
关键词 RH血型 交叉配血不合 Rh同型输注
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