Journal of Geriatric Psychiatry and Neurology, 2008
The purpose of this study was to examine the association between dependence in activities of dail... more The purpose of this study was to examine the association between dependence in activities of daily living (ADL) and instrumental ADL (IADL) and major depression among 415 community-dwelling primary care patients age 65+ with heart failure and significant ADL or IADL dependence. Main findings include (1) a progressive increase in depression prevalence from 0% for no IADL dependence to about 40% for 6 IADL dependencies (P < .001), (2) a steady rise in depression prevalence to 40% for 6 ADL dependencies following a "floor effect" at about 10% for 0 to 2 ADL dependencies (P < .001), and (3) the association in a logistic regression model of major depression with number of IADL dependencies (P = .016) but not with number of ADL dependencies (P = .602). Our principal conclusion is that the progressively greater likelihood of major depression as the number of IADL dependencies increases has important clinical, personal, social, and public health relevance.
OBJECTIVES: To determine the performance of the Patient Health Questionnaire 2 (PHQ-2) against th... more OBJECTIVES: To determine the performance of the Patient Health Questionnaire 2 (PHQ-2) against the criterion standard for diagnosing major depression, the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), and to examine its performance across age, sex, and racial/ethnic groups.DESIGN: Cross-sectional observational study.SETTING: The National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) (2001/02), a nationally representative survey of the noninstitutionalized U.S. household population.PARTICIPANTS: The 8,205 adults aged 65 and older who participated in NESARC.MEASUREMENTS: The PHQ-2's criterion validity (sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) against the DSM-IV) and construct validity (Spearman correlations between the PHQ-2 and the six scales of the Medical Outcomes Study 12-item Short Form Questionnaire (SF-12)) were calculated.RESULTS: The PHQ-2's criterion validity for major depression was good (sensitivity=100%, specificity=77%, AUC=0.88). Its sensitivity was 100% for each subgroup. Specificity increased with age, was higher for men than for women, and differed across racial and ethnic groups. For the total sample and each sex, all six SF-12 scales were significantly lower in people who tested positive using the PHQ-2. For each age and racial or ethnic group, most of the six scales differed significantly between those who tested positive and tested negative.CONCLUSION: The PHQ-2 is a valid screening tool for major depression in older people but should be followed by a more-comprehensive diagnostic process. Although its specificity differs by age, sex, and racial and ethnic groups, these differences appear to be of little clinical significance.
This paper presents the mode I stress intensity factors for functionally graded solid cylinders w... more This paper presents the mode I stress intensity factors for functionally graded solid cylinders with an embedded penny-shaped crack or an external circumferential crack. The solid cylinders are assumed under remote uniform tension. The multiple isoparametric finite element method is used. Various types of functionally graded materials and different gradient compositions for each type are investigated. The results show that
... Rev. B 66, 233402 (2002). ES Snow, PM Campbell, and JP Novak, “Single-wall carbon nanotube at... more ... Rev. B 66, 233402 (2002). ES Snow, PM Campbell, and JP Novak, “Single-wall carbon nanotube atomic force microscope probes,” Appl. Phys. Lett. 80, 2002 (2002). CY Li and TW Chou, Int. ... L. Meirovich, Elements of Vibration Analysis, 2nd ed. (McGraw-Hill, New York, 1986). ...
... Nat-suki et al.17 treated CNTs as multilayer thin shells, and ana-lyzed transverse wave propa... more ... Nat-suki et al.17 treated CNTs as multilayer thin shells, and ana-lyzed transverse wave propagation in SWCNTs and double-walled CNTs, as well as nanotubes embedded in an elastic matrix. ... Res. 32, 347 2002. 10 KM Liew, CH Wong, XQ He, MJ Tan, and SA Meguid, Phys. ...
We extend the molecular structural mechanics approach to the study of the specific heat of carbon... more We extend the molecular structural mechanics approach to the study of the specific heat of carbon nanotubes. The vibrational modes of the nanotube are quantized according to the theory of quantum mechanics. The partition function is directly expressed by the vibrational frequencies of carbon atoms. The specific heat of finite-length individual single-walled carbon nanotubes is calculated and the temperature dependence
This paper reports a multiscale modeling of the compressive behavior of carbon nanotube/polymer c... more This paper reports a multiscale modeling of the compressive behavior of carbon nanotube/polymer composites. The nanotube is modeled at the atomistic scale, and the matrix deformation is analyzed by the continuum finite element method. The nanotube and ...
Journal of Geriatric Psychiatry and Neurology, 2008
The purpose of this study was to examine the association between dependence in activities of dail... more The purpose of this study was to examine the association between dependence in activities of daily living (ADL) and instrumental ADL (IADL) and major depression among 415 community-dwelling primary care patients age 65+ with heart failure and significant ADL or IADL dependence. Main findings include (1) a progressive increase in depression prevalence from 0% for no IADL dependence to about 40% for 6 IADL dependencies (P < .001), (2) a steady rise in depression prevalence to 40% for 6 ADL dependencies following a "floor effect" at about 10% for 0 to 2 ADL dependencies (P < .001), and (3) the association in a logistic regression model of major depression with number of IADL dependencies (P = .016) but not with number of ADL dependencies (P = .602). Our principal conclusion is that the progressively greater likelihood of major depression as the number of IADL dependencies increases has important clinical, personal, social, and public health relevance.
OBJECTIVES: To determine the performance of the Patient Health Questionnaire 2 (PHQ-2) against th... more OBJECTIVES: To determine the performance of the Patient Health Questionnaire 2 (PHQ-2) against the criterion standard for diagnosing major depression, the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), and to examine its performance across age, sex, and racial/ethnic groups.DESIGN: Cross-sectional observational study.SETTING: The National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) (2001/02), a nationally representative survey of the noninstitutionalized U.S. household population.PARTICIPANTS: The 8,205 adults aged 65 and older who participated in NESARC.MEASUREMENTS: The PHQ-2's criterion validity (sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) against the DSM-IV) and construct validity (Spearman correlations between the PHQ-2 and the six scales of the Medical Outcomes Study 12-item Short Form Questionnaire (SF-12)) were calculated.RESULTS: The PHQ-2's criterion validity for major depression was good (sensitivity=100%, specificity=77%, AUC=0.88). Its sensitivity was 100% for each subgroup. Specificity increased with age, was higher for men than for women, and differed across racial and ethnic groups. For the total sample and each sex, all six SF-12 scales were significantly lower in people who tested positive using the PHQ-2. For each age and racial or ethnic group, most of the six scales differed significantly between those who tested positive and tested negative.CONCLUSION: The PHQ-2 is a valid screening tool for major depression in older people but should be followed by a more-comprehensive diagnostic process. Although its specificity differs by age, sex, and racial and ethnic groups, these differences appear to be of little clinical significance.
This paper presents the mode I stress intensity factors for functionally graded solid cylinders w... more This paper presents the mode I stress intensity factors for functionally graded solid cylinders with an embedded penny-shaped crack or an external circumferential crack. The solid cylinders are assumed under remote uniform tension. The multiple isoparametric finite element method is used. Various types of functionally graded materials and different gradient compositions for each type are investigated. The results show that
... Rev. B 66, 233402 (2002). ES Snow, PM Campbell, and JP Novak, “Single-wall carbon nanotube at... more ... Rev. B 66, 233402 (2002). ES Snow, PM Campbell, and JP Novak, “Single-wall carbon nanotube atomic force microscope probes,” Appl. Phys. Lett. 80, 2002 (2002). CY Li and TW Chou, Int. ... L. Meirovich, Elements of Vibration Analysis, 2nd ed. (McGraw-Hill, New York, 1986). ...
... Nat-suki et al.17 treated CNTs as multilayer thin shells, and ana-lyzed transverse wave propa... more ... Nat-suki et al.17 treated CNTs as multilayer thin shells, and ana-lyzed transverse wave propagation in SWCNTs and double-walled CNTs, as well as nanotubes embedded in an elastic matrix. ... Res. 32, 347 2002. 10 KM Liew, CH Wong, XQ He, MJ Tan, and SA Meguid, Phys. ...
We extend the molecular structural mechanics approach to the study of the specific heat of carbon... more We extend the molecular structural mechanics approach to the study of the specific heat of carbon nanotubes. The vibrational modes of the nanotube are quantized according to the theory of quantum mechanics. The partition function is directly expressed by the vibrational frequencies of carbon atoms. The specific heat of finite-length individual single-walled carbon nanotubes is calculated and the temperature dependence
This paper reports a multiscale modeling of the compressive behavior of carbon nanotube/polymer c... more This paper reports a multiscale modeling of the compressive behavior of carbon nanotube/polymer composites. The nanotube is modeled at the atomistic scale, and the matrix deformation is analyzed by the continuum finite element method. The nanotube and ...
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