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Early-life famine exposure, adulthood obesity patterns, and risk of low-energy fracture

《医学前沿(英文)》 doi: 10.1007/s11684-023-1023-9

摘要: Malnutrition in early life increases the risk of osteoporosis, but the association of early-life undernutrition combined with adulthood obesity patterns with low-energy fracture remains unknown. This study included 5323 community-dwelling subjects aged ≥40 years from China. Early-life famine exposure was identified based on the participants’ birth dates. General obesity was assessed using the body mass index (BMI), and abdominal obesity was evaluated with the waist-to-hip ratio (WHR). Low-energy fracture was defined as fracture occurring after the age of 40 typically caused by falls from standing height or lower. Compared to the nonexposed group, the group with fetal, childhood, and adolescence famine exposure was associated with an increased risk of fracture in women with odds ratios (ORs) and 95% confidence intervals (CIs) of 3.55 (1.57–8.05), 3.90 (1.57–9.71), and 3.53 (1.05–11.88), respectively, but not in men. Significant interactions were observed between fetal famine exposure and general obesity with fracture among women (P for interaction = 0.0008). Furthermore, compared with the groups with normal BMI and WHR, the group of women who underwent fetal famine exposure and had both general and abdominal obesity had the highest risk of fracture (OR, 95% CI: 3.32, 1.17–9.40). These results indicate that early-life famine exposure interacts with adulthood general obesity and significantly increases the risk of low-energy fracture later in life in women.

关键词: famine     obesity     body mass index     waist-to-hip ratio     low-energy fracture    

The correlated study of hyperuricemia and metabolic syndromes among males of Han ethnicity in the Xinjiang Uygur Autonomous Region, China

YAO Hua, SUN Yuping, LI Qing, YAO Wenhai, WANG Qiuyun, HU Jing, ABUDUREHEMAN Gulibaha, TUO Ling, JIANG Yan

《医学前沿(英文)》 2008年 第2卷 第1期   页码 108-112 doi: 10.1007/s11684-008-0020-3

摘要: This study investigates the relationship between hyperuricemia and metabolic syndrome (MS) among males of Han ethnicity in the Xinjiang Uygur Autonomous Region, China. The blood samples were collected from January to May, 2006 in Urumqi. It included 1496 subjects with ages between 20 to 70 years. All these subjects had physical examinations, blood pressure (BP) measurement and analysis for serum uric acid (SUA), fasting blood sugar (FBS), serum triglyceride (TG), serum total cholesterol (TC), serum high density lipoprotein (HDL-C) and serum low density lipoprotein (LDL-C) as well as biochemistry assay. The Data were analyzed using the Pearson Chi-Square Test, Independent-Samples -Test and the Mantel-Haenszel Test for linear trend, respectively. The results show that the prevalence of MS in the present study was 18%. Blood pressure, fasting blood sugar, body mass index (BMI), waist/hip ratio(WHR), TG, TC and LDL-C were significantly higher in the hyperuricemic group than in normal group and these parameters were strongly related to serum uric acid levels. The components of metabolic syndrome such as obesity, hyperglycemia, hypertension and dyslipidemia had a close correlation with SUA. The Odds ratios of these metabolic diseases in the hyperuricemic group were 3.097 times, 2.633 times, 2.226 times and 3.058 times of the normal SUA group, respectively. They all have a positive correlation with hyperuricemia. Hyperuricemia is closely linked to the various components of the metabolic syndrome. More emphasis should be put on the evolving control and prevalence of hyperuricemia and metabolic syndrome among males of Han ethnicity in Xinjiang.

关键词: control     prevalence     waist/hip     density lipoprotein     hypertension    

基于人体髋关节转动中心分析的髋关节外骨骼仿生设计 Article

Wei YANG,Can-jun YANG,Ting XU

《信息与电子工程前沿(英文)》 2016年 第17卷 第8期   页码 792-802 doi: 10.1631/FITEE.1500286

摘要: 为了改善外骨骼穿戴舒适性,本文提出了一种基于人机物理交互优化的外骨骼设计方法。该方法通过设计外骨骼髋关节,使其保证人体髋关节运动时外骨骼髋关节转动中心能跟随人体髋关节转动中心的运动轨迹。当人体髋关节运动时,通过实验测量和计算可以得到其转动中心轨迹。本文设计的外骨骼髋关节运动机构能在人体髋关节屈曲/伸展和外展/内收时,保证转动中心都能够包容人体髋关节转动中心运动范围。同时,所设计的外骨骼髋关节被应用到下肢步行康复训练外骨骼中。通过人机接触力实验可知,与传统设计外骨骼髋关节进行相比,本文设计的仿生髋关节外骨骼在髋关节屈曲/伸展和内收/外展时分别可以减小24.1%和76.0%的人机接触力。这一结果证明仿生设计髋关节外骨骼更具穿戴舒适性,更符合人机工程学的设计要求。最后,本文通过建立人机闭式链模型进一步分析了仿生设计对于人体髋关节内力的影响,并验证该设计能减少关节内力作用。

关键词: 髋关节外骨骼;髋关节中心;柔顺关节;人机交互力    

Push recovery for the standing under-actuated bipedal robot using the hip strategy

Chao LI,Rong XIONG,Qiu-guo ZHU,Jun WU,Ya-liang WANG,Yi-ming HUANG

《信息与电子工程前沿(英文)》 2015年 第16卷 第7期   页码 579-593 doi: 10.1631/FITEE.14a0230

摘要: This paper presents a control algorithm for push recovery, which particularly focuses on the hip strategy when an external disturbance is applied on the body of a standing under-actuated biped. By analyzing a simplified dynamic model of a bipedal robot in the stance phase, it is found that horizontal stability can be maintained with a suitably controlled torque applied at the hip. However, errors in the angle or angular velocity of body posture may appear, due to the dynamic coupling of the translational and rotational motions. To solve this problem, different hip strategies are discussed for two cases when (1) external disturbance is applied on the center of mass (CoM) and (2) external torque is acting around the CoM, and a universal hip strategy is derived for most disturbances. Moreover, three torque primitives for the hip, depending on the type of disturbance, are designed to achieve translational and rotational balance recovery simultaneously. Compared with closed-loop control, the advantage of the open-loop methods of torque primitives lies in rapid response and reasonable performance. Finally, simulation studies of the push recovery of a bipedal robot are presented to demonstrate the effectiveness of the proposed methods.

关键词: Push recovery     Balance control     Bipedal robot     Hip strategy    

3D打印髋关节假体为复杂髋臼骨缺损翻修全髋关节置换术提供精准重建、稳定固定和功能恢复 Article

郝永强, 王磊, 姜闻博, 武文, 艾松涛, 沈路, 赵双, 戴尅戎

《工程(英文)》 2020年 第6卷 第11期   页码 1285-1290 doi: 10.1016/j.eng.2020.04.013

摘要:

复杂而严重的髋臼骨缺损是人工髋关节置换术重建过程中最主要的挑战和难点。本研究旨在探讨3D打印技术在重建这种复杂髋臼骨缺损中的优势。我们回顾性分析了3例使用3D打印技术治疗的复杂髋臼骨缺损患者的预后,其中一例患者涉及双侧缺损重建。这些髋臼骨缺损的共同特点为常规方法难以重建。因此,在本研究中,我们首先结合了医学影像学分析、计算机软件模拟和重建(如MIMICS软件和西门子NX软件)及实际手术经验对缺损体积、假体重建稳定性和假体安装精度进行预测和评估,Harris髋关节评分被用来评估肢体功能。我们的结果表明3D打印假体可以精准重建骨缺损,并获得良好的假体稳定性,并且Harris髋关节评分显示3位患者肢体功能得到较好的恢复。总而言之,3D打印技术在人工髋关节翻修术中应对复杂且程度较为严重的骨缺损具有非常好的治疗效果,最终患者获得满意的预后。

关键词: 3D打印     髋关节翻修     复杂严重髋臼骨缺损     精准重建    

Value of waist circumference, body mass index and hyperinsulinaemia in identifying metabolic syndrome

TIAN Hui, FANG Fusheng, SHAO Yinghong, LI Chunlin, LI Jian, YAN Shuangtong, ZHONG Wenwen, LI Yanyan, SUN Jingfang, CAO Xiutang, PAN Changyu, LU Juming, DOU Jingtao, MA Fangling, ZHOU Xiaoman

《医学前沿(英文)》 2008年 第2卷 第4期   页码 400-405 doi: 10.1007/s11684-008-0077-z

摘要: To investigate the significance of waist circumference (WC), body mass index (BMI) and hyperinsulinaemia A (HIns) in evaluating metabolic syndrome (MS). Clinical data from middle-aged and senile individuals (middle-senile group) who received glucose tolerance test after diabetes mellitus screening and a group of subjects who received annual oral glucose tolerance test (OGTT) for diabetes mellitus screening (adult group) were collected. Data were collected by use of special messengers, input into a computer data base and analyzed using SAS 5.0 software by expert staff. Abnormal WC and BMI were determined according to International Diabetes Federation (IDF) and Chinese Diabetes Society (CDS) criteria. HIns was ascertained if fasting insulin (FIns) ≥ 15 mU/L, and/or 2-hour insulin after a glucose challenge was (2hPIns) ≥ 80 mU/L. Abnormalities in WC, BMI and HIns were all found to be risk factors for abnormal glucose metabolism, hypertension and dyslipidemia. In the middle-senile group, the abnormality rate of WC and HIns as well as the overall insulin level were significantly higher than those in the adult group. The abnormality rate of BMI was higher in the adult group, and HIns was mostly seen in impaired glucose test (IGT) and normal glucose test (NGT). The concordance rate of WC and BMI diagnostic criteria for evaluating obesity in the middle-senile and adult groups were 77.5% and 74.3%, respectively. When only the WC criterion was used for evaluating the existence of insulin resistance, there was a 28.2% missed diagnosis rate for MS patients. WC, BMI and HIns were all risk factors for abnormal glucose metabolism, hypertension and dyslipidemia. There was differing prevalence in the different populations. The combination of WC, BMI and HIns might be more helpful in identifying MS at early stage.

关键词: mU/L     prevalence     Abnormal     dyslipidemia     computer    

油压极值比与极值比效率

齐茂林

《中国工程科学》 2001年 第3卷 第4期   页码 73-75

摘要:

文章应用基础公式,推导液压系统油压极值比与极值比效率之间的关系式。该式说明,油压极值比越大,极值比效率就越低。提出了油压极值比是可以设计和选择的。

关键词: 油压极值比     极值比效率     液压系统    

Controlling interstory drift ratio profiles via topology optimization strategies

《结构与土木工程前沿(英文)》 2023年 第17卷 第2期   页码 165-178 doi: 10.1007/s11709-022-0892-3

摘要: An approach to control the profiles of interstory drift ratios along the height of building structures via topology optimization is proposed herein. The theoretical foundation of the proposed approach involves solving a min–max optimization problem to suppress the maximum interstory drift ratio among all stories. Two formulations are suggested: one inherits the bound formulation and the other utilizes a p-norm function to aggregate all individual interstory drift ratios. The proposed methodology can shape the interstory drift ratio profiles into inverted triangular or quadratic patterns because it realizes profile control using a group of shape weight coefficients. The proposed formulations are validated via a series of numerical examples. The disparity between the two formulations is clear. The optimization results show the optimal structural features for controlling the interstory drift ratios under different requirements.

关键词: interstory drift ratio     aggregation function     bound formulation     min–max problem     topology optimization    

Toward the development of process plans with reduced environmental impacts

Fu ZHAO, Vance R. MURRAY, Karthik RAMANI, John W. SUTHERLAND

《机械工程前沿(英文)》 2012年 第7卷 第3期   页码 231-246 doi: 10.1007/s11465-012-0334-3

摘要:

Manufacturing process planning serves as a pivotal link between design and manufacturing. Process planning decisions play a critical role in determining the cost and environmental impacts associated with manufacturing. Past efforts to address environmental issues during process planning are briefly reviewed and potential approaches that can achieve reduced environmental impacts are then discussed. A proposed method is presented for environmentally conscious process planning. The method begins with an existing process plan, and then identifies impactful process steps, and associated design features, in terms of manufacturing cost and environmental impact. Alternative processes that can achieve these features are then considered to generate alternative process plans. These alternatives are then evaluated in terms of economic and environmental performance. The results of these evaluations are then used to generate a set of process plans that are non-dominated with respect to manufacturing cost and environmental impact objectives to produce a Pareto frontier. The proposed method is demonstrated using the manufacturing of a prosthetic hip shell as a case study.

关键词: process planning     life cycle assessment (LCA)     sustainable manufacturing     prosthetic hip shell    

A methodology of implementing target mixing ratio for asphalt mixture

Yucheng HUANG, Lun JI, Rui WEN, Ming ZHANG

《结构与土木工程前沿(英文)》 2017年 第11卷 第3期   页码 308-314 doi: 10.1007/s11709-017-0405-y

摘要: In order to implement the objective mix design of hot mix asphalt adequately during the construction process, the significance of objective mixing ratio was elaborated, and the variability of materials and its control method were analyzed. An engineering example is used to illustrate the debugging process of asphalt mixture batching & mixing plant and the dynamic quality management methods. The results show that the set of methods can not only implement the objective mixing ratio of hot mix asphalt adequately, but also control production during the construction process effectively.

关键词: asphalt mixture     target mixing ratio     mix design implementation     batching & mixing plant debugging    

Hip-mounted electromagnetic generator to harvest energy from human motion

Dan DAI,Jing LIU

《能源前沿(英文)》 2014年 第8卷 第2期   页码 173-181 doi: 10.1007/s11708-014-0301-2

摘要: A type of electromagnetic hip-mounted generator (EHG) is proposed to harvest energy from human hip motion to generate electricity. Based on the law of electromagnetic induction, the EHG generator can convert the kinetic power of the thigh swing into electrical energy during walking or running. To demonstrate the feasibility of the present method, a prototype of the EHG has been designed and fabricated. A theoretical analysis has been conducted to interpret the working behavior of this prototype. In addition, the performance of the system has been experimentally tested through a rotary motor and human body motion. When driven by the rotary motor at a rotation speed of 100 r/min, the open-circuit voltage of this prototype is 2.5 V. Further, a maximum open-circuit voltage of approximately 1 V and a maximum output power of 284 μW could be produced respectively when walking with an EHG at a speed of 1.47 m/s. This handy renewable energy technology is promising as a pervasive electricity generation system for a group of wearable or implanted sensors, actuators and mobile electronics.

关键词: human power harvesting     pervasive energy     electricity generation     wearable energy     renewable and sustainable energy     mobile electronics    

Diagnostic evaluation of plasma aldosterone concentration to plasma renin activity ratio in primary aldosteronism

ZHANG Huilan, WANG Daowen

《医学前沿(英文)》 2008年 第2卷 第1期   页码 11-14 doi: 10.1007/s11684-008-0003-4

摘要: Using the plasma aldosterone concentration to plasma renin activity ratio (PAC/PRA ratio) as the screening test of choice for primary aldosteronism in hypertensive patients, we studied the clinical characteristics and the diagnostic value of PAC/PRA ratio in primary aldosteronism. The plasma aldosterone concentration (PAC) and plasma renin activity (PRA) levels were measured by radioimmunoassay in 902 hypertensive patients from out-patient clinics or hospitals. One hundred and twenty-six suspected primary aldosteronism patients whose PAC/PRA ratio was > 25 ng/dL/ng/mL/hr had a lamellar computed tomography (CT) scan in the adrenal gland and follow-up visits. The proportion of primary aldosteronism in hypertensive patients was 14% (126/902). There were 54 patients with unilateral or bilateral hyperplasia and 25 patients with adenoma according to the CT scan. 39% (49/126) of the patients with primary aldosteronism had hypokalemia. Twenty-five patients received surgical treatment. The efficacy and cure rates were 100% (25/25) and 48% (12/25), respectively. The effective rate of aldactone and the single-drug cure rate were 89% (48/54) and 24% (13/54), respectively. Primary aldosteronism affects over 10% of hypertensive patients in China. The PAC/PRA ratio can be considered as a routine screening test in hypertensives, especially resistant hypertensive patients and a high PAC/PRA ratio is an invaluable index in primary aldosteronism diagnosis.

Enhancing the efficiency of nitrogen removing bacterial population to a wide range of C:N ratio (1.5:

《环境科学与工程前沿(英文)》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1522-y

摘要:

• Simultaneous C & N removal in Methammox occurs at wide C:N ratio.

关键词: Methanogens     Biological Nitrogen Removal (BNR)     Simultaneous     Methammox     C:N ratio    

Experimental study of structural damage identification based on modal parameters and decay ratio of acceleration

Zhigen WU, Guohua LIU, Zihua ZHANG

《结构与土木工程前沿(英文)》 2011年 第5卷 第1期   页码 112-120 doi: 10.1007/s11709-010-0069-3

摘要: A novel damage assessment method based on the decay ratio of acceleration signals (DRAS) was proposed. Two experimental tests were used to show the efficiency. Three beams were gradually damaged, and then the changes of dynamic parameters were monitored from initial to failure state. In addition, a new method was compared with the linear modal-based damage assessment using wavelet transform (WT). The results clearly show that DRAS increases in linear elasticity state and microcrack propagation state, while DRAS decreases in macrocrack propagation state. Preliminary analysis was developed considering the beat phenomenon in the nonlinear state to explain the turn point of DRAS. With better sensibility of damage than modal parameters, probably DRAS is a promising damage indicator in damage assessment.

关键词: damage assessment     decay ratio of acceleration signals (DRAS)     wavelet transform (WT)     modal analysis     reinforced concrete beam     beat phenomenon    

The influence of the NCO/OH ratio and the 1,6-hexanediol/dimethylol propionic acid molar ratio on the

Jiao Feng, Qiuhao Lu, Weimin Tan, Kequan Chen, Pingkai Ouyang

《化学科学与工程前沿(英文)》 2019年 第13卷 第1期   页码 80-89 doi: 10.1007/s11705-018-1763-2

摘要:

1,5-Pentamethylene diisocyanate, a novel aliphatic diisocyanate formed from bio-based 1,5-pentamethylenediamine, has been used as a hard segmented material to synthesize polyurethane. In this study, several waterborne polyurethane (WPU) dispersions have been successfully prepared by a prepolymer process from 1,5-pentamethylene diisocyanate poly(polyether) with different NCO/OH ratios and 1,6-hexanediol (HDO)/dimethylol propionic acid (DMPA) molar ratios. The Fourier transform infrared (FTIR) spectra, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, and a mechanical tensile test were used to investigate the structures, thermal stability, phase separation, crystallinity, mechanical properties, and adhesive performance of the WPU dispersions. The FTIR results indicate that the degree of hydrogen bonding and the numbers of urea groups increase as the NCO/OH ratio and HDO/DMPA molar ratio increase. Furthermore, the phase separation increases and the thermal stability decreases as the NCO/OH ratio increases or the HDO/DMPA molar ratio decreases. Finally, WPU3.0-2.4 (NCO/OH=3, HDO/DMPA=2.4) exhibits a maximum tensile strength and shear strength, pointing to its possible use as an adhesive. These results could provide a very valuable reference for industrial applications of WPU.

关键词: 1     5-pentamethylene diisocyanate     polyurethane     water based    

标题 作者 时间 类型 操作

Early-life famine exposure, adulthood obesity patterns, and risk of low-energy fracture

期刊论文

The correlated study of hyperuricemia and metabolic syndromes among males of Han ethnicity in the Xinjiang Uygur Autonomous Region, China

YAO Hua, SUN Yuping, LI Qing, YAO Wenhai, WANG Qiuyun, HU Jing, ABUDUREHEMAN Gulibaha, TUO Ling, JIANG Yan

期刊论文

基于人体髋关节转动中心分析的髋关节外骨骼仿生设计

Wei YANG,Can-jun YANG,Ting XU

期刊论文

Push recovery for the standing under-actuated bipedal robot using the hip strategy

Chao LI,Rong XIONG,Qiu-guo ZHU,Jun WU,Ya-liang WANG,Yi-ming HUANG

期刊论文

3D打印髋关节假体为复杂髋臼骨缺损翻修全髋关节置换术提供精准重建、稳定固定和功能恢复

郝永强, 王磊, 姜闻博, 武文, 艾松涛, 沈路, 赵双, 戴尅戎

期刊论文

Value of waist circumference, body mass index and hyperinsulinaemia in identifying metabolic syndrome

TIAN Hui, FANG Fusheng, SHAO Yinghong, LI Chunlin, LI Jian, YAN Shuangtong, ZHONG Wenwen, LI Yanyan, SUN Jingfang, CAO Xiutang, PAN Changyu, LU Juming, DOU Jingtao, MA Fangling, ZHOU Xiaoman

期刊论文

油压极值比与极值比效率

齐茂林

期刊论文

Controlling interstory drift ratio profiles via topology optimization strategies

期刊论文

Toward the development of process plans with reduced environmental impacts

Fu ZHAO, Vance R. MURRAY, Karthik RAMANI, John W. SUTHERLAND

期刊论文

A methodology of implementing target mixing ratio for asphalt mixture

Yucheng HUANG, Lun JI, Rui WEN, Ming ZHANG

期刊论文

Hip-mounted electromagnetic generator to harvest energy from human motion

Dan DAI,Jing LIU

期刊论文

Diagnostic evaluation of plasma aldosterone concentration to plasma renin activity ratio in primary aldosteronism

ZHANG Huilan, WANG Daowen

期刊论文

Enhancing the efficiency of nitrogen removing bacterial population to a wide range of C:N ratio (1.5:

期刊论文

Experimental study of structural damage identification based on modal parameters and decay ratio of acceleration

Zhigen WU, Guohua LIU, Zihua ZHANG

期刊论文

The influence of the NCO/OH ratio and the 1,6-hexanediol/dimethylol propionic acid molar ratio on the

Jiao Feng, Qiuhao Lu, Weimin Tan, Kequan Chen, Pingkai Ouyang

期刊论文