[show abstract] [hide abstract]
ABSTRACT: Turning gait is a basic motion for humanoid robots. This paper presents a method for humanoid turning, i.e. clock-turning. The objective of clock-turning is to change robot direction at a stationary spot. The clock-turning planning consists of four steps: ankle trajectory generation, hip trajectory generation, knee trajectory generation, and inverse kinematics calculation. Our proposed method is based on a typical humanoid structure with 12 DOFs (degrees of freedom). The final output of clock-turning planning is 12 reference trajectories, which are used to control a humanoid robot with 12 DOFs. ZMP (zero moment point) is used as stability criterion for the planning. Simulation experiments are conducted to verify the effectiveness of our proposed clock-turning method.Journal of Control Theory and Applications 04/2012; 5(1):23-27.
Article: [A cohort study on mortality and risk of death among population diagnosis as dementia, at base-line survey, in Beijing].[show abstract] [hide abstract]
ABSTRACT: To study the mortality and risk of death on dementia among ageing population. A random sample including 2788 elderly residents was studied. Dementia was diagnosed under the two-phase procedure in 1997. In phase 1, questionnaire was administered, including the Mini-Mental State Examination (MMSE) tested. In phase 2, all the elderly who showed low MMSE score and some with normal MMSE score, were examined by neurologists. The clinical diagnosis of dementia was set up by two neurologists according to the criteria of DSM-III-R and NINCDS-ADRDA. The same sample was followed up in 2000 and 2004 the same way and data on deaths and causes was gathered. The overall time for follow-up was 7.25 years. 171 cases with dementia were diagnosed from 2788 subjects in 1997, with a crude death rate (CDR) of dementia was 7.8 per 1000 person-years and age-standardized CDR as 5.5 per 1000 person-years. The death rate was increased exponentially with age. In the dementia group, the total number of deaths was 133, with the CDR as 236 per 1000 person-years and the age-standardized CDR as 206 per 1000 person-years, in the end of the survey. In the non-dementia group, the total number of deaths was 680, with CDR as 40 per 1000 person-years and the age-standardized CDR as 31 per 1000 person-years. The difference in the two groups was statistically significant. The hazard ratio (HR) of dementia death appeared to be the biggest in the 60 - 74 - year group than the other groups. Data was analyzed with the Cox proportional hazards model after making necessary adjustment on potential covariates with the HR of dementia as 2.181 (95%CI: 1.751 - 2.717). The HRs were 2.524 (95%CI: 1.964 - 3.243) in Alzheimer's disease and 1.859 (95%CI: 1.213 - 2.850) in vascular dementia. The CDR and HR of dementia were higher than the non-dementia group in the aging population, showing that dementia was one of the most important risk factors on death in the aging population.Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 10/2011; 32(10):973-7.
Article: [Regional disparity on life expectancy, active life expectancy in the elderly from Beijing].[show abstract] [hide abstract]
ABSTRACT: To explore the regional disparity in life expectancy (LE), active life expectancy (ALE), active life expectancy/life expectancy (ALE/LE) of the elderly in Beijing and to express the impact of hypertension upon those indices. The sample was derived from a "Beijing multidimensional longitudinal study on aging", including those from urban district (Xuanwu), rural district (Daxing and Huairou) by well-established statistical sampling techniques. Baseline survey comprised 1847 people aged 60 years or over, living in the communities in Beijing in 2004. The subjects under research were investigated with questionnaires at home by well-trained interviews and the contents would include: degree of education, occupation, medical history of hypertension together with repeated blood pressure measurements. Someone being "active" was defined as the ability in performing activities of daily life (ADL). IMaCH software for multi-state life table method was used to calculate the life expectancy (LE), active life expectancy (ALE) and active life expectancy/life expectancy (ALE/LE) in different district and the hypertensive exert influence on those indices. Data from the study showed that people inhabited in the rural district had lower LE, ALE and degree of education (illiteracy account for 66.2 percentage), but with more physical activities (account for 95.5 percentage) and higher ALE/LE than urban district people. Regional disparity in Females was obvious than in males while hypertension would exert more influence on LE of the urban women, which widened the gap in LE, ALE of males and ALE of females between the urban and rural areas. Regional disparity was found existing in LE, ALE, ALE/LE of the elderly from Beijing, particularly in females. Hypertension widened the gap and decreased the quality of life on senior citizens in the rural areas. This finding underlined the influence of habitation on the quality of life which manifested the importance of prevention regarding high blood pressure.Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 09/2011; 32(9):864-8.
Article: Development and Application of a Biorelevant Dissolution Method Using USP Apparatus 4 in Early Phase Formulation Development.Jiang B Fang, Vivian K Robertson, Archana Rawat, Tawnya Flick, Zhe J Tang, Nina S Cauchon, James S McElvain[show abstract] [hide abstract]
ABSTRACT: Dissolution testing is frequently used to determine the rate and extent at which a drug is released from a dosage form, and it plays many important roles throughout drug product development. However, the traditional dissolution approach often emphasizes its application in quality control testing and usually strives to obtain 100% drug release. As a result, dissolution methods are not necessarily biorelevant and meaningful application of traditional dissolution methods in the early phases of drug product development can be very limited. This article will describe the development of a biorelevant in vitro dissolution method using USP apparatus 4, biorelevant media, and real-time online UV analysis. Several case studies in the areas of formulation selection, lot-to-lot variability, and food effect will be presented to demonstrate the application of this method in early phase formulation development. This biorelevant dissolution method using USP apparatus 4 provides a valuable tool to predict certain aspects of the in vivo drug release. It can be used to facilitate the formulation development/selection for pharmacokinetic (PK) and clinical studies. It may also potentially be used to minimize the number of PK studies, and to aid in the design of more efficient PK and clinical studies.Molecular Pharmaceutics 09/2010; · 4.78 Impact Factor
Article: The relationship between apolipoprotein (apo) E polymorphism and lipid changes: An 8-year cohort study in Beijing elderly persons.[show abstract] [hide abstract]
ABSTRACT: This study aimed to investigate the influence of apoE genetic polymorphism on serum lipid changes in a community-based elderly population in China in an 8-year period, in which 746 individual, aged 65.29±6.85 years (mean±standard deviation (SD)) were enrolled and serum lipid parameters were checked at baseline. After 8 years, serum lipids as well as apoE genotypes were measured. The frequencies of apoE allele were 9.4%, 81.7%, and 8.9% for ɛ2, ɛ3 and ɛ4, respectively. After the population was divided into 3 groups by different apoE allele carriers, the apoE allele carriers for ɛ2, ɛ3 and ɛ4 were 121 (16.2%), 513 (68.8%) and 112 (15.0%), respectively. Levels of total cholesterol (TC) and low density lipoprotein (LDL) in ɛ2 carriers were lower comparing with that of ɛ3 allele carriers at baseline. 8 years later, TC and high density lipoprotein (HDL) elevated and LDL decreased with aging in this population (p<0.01). The changes of TC levels were smaller in ɛ2 allele carriers as compared to that of ɛ3 allele carriers. The difference was still statistically significant after controlling for age, sex, smoking status, drinking habit, body mass index (BMI) and baseline TC level. The same trend of changes was noted for LDL between ɛ2 and ɛ3 allele carriers. However, no significant differences were noted between ɛ4 and ɛ3 allele carriers on lipid changes. This community-based study shows that ɛ2 allele is helpful on lipid changes. The effect of ɛ4 allele on lipid change is not strong in this elderly population. Genetic and environmental factors maybe co-operate on lipid metabolism in elderly persons.Archives of gerontology and geriatrics 12/2011; 55(3):713-7. · 1.36 Impact Factor