An inverse analysis for determination of space-dependent heat flux in heat conduction problems in the presence of variable thermal conductivity

Translator disclaimer Full Article Figures & data References Citations Metrics Reprints & Permissions Get accessAbstractThis article presents an inverse problem of determination of a space-dependent heat flux in steady-state heat conduction problems. The thermal conductivity of a heat conducting body depends on the temperature distribution over the body. In this study, the simulated measured temperature distribution on part of the boundary is related to the variable heat flux imposed on a different part of the boundary through incorporating the variable thermal conductivity components into the sensitivity coefficients. To do so, a body-fitted grid generation technique is used to mesh the two-dimensional irregular body and solve the direct heat conduction problem. An efficient, accurate, robust, and easy to implement method is presented to compute the sensitivity coefficients through derived expressions. Novelty of the study is twofold: (1) Boundary-fitted grid-based sensitivity analysis in which all sensitivities can be obtained in only one direct solution (at each iteration), irrespective of the number of unknown parameters, and (2) the way the measured temperatures on part of boundary are related to a variable heat flux applied on another part of boundary through components of a variable thermal conductivity. The conjugate gradient method along with the discrepancy principle is used in the inverse analysis to minimize the objective function and achieve the desired solution

Health‐Related Quality of Life in Kidney Donors From the Last Five Decades: Results From the RELIVE Study

Live donation benefits recipients, but the long‐term consequences for donors remain uncertain. Renal and Lung Living Donors Evaluation Study surveyed kidney donors (N = 2455; 61% women; mean age 58, aged 24–94; mean time from donation 17 years, range 5–48 years) using the Short Form‐36 Health Survey (SF‐36). The 95% confidence intervals for White and African‐American donors included or exceeded SF‐36 norms. Over 80% of donors reported average or above average health for their age and sex (p 1 SD below norm). Obesity, history of psychiatric difficulties and non‐White race were risk factors for impaired physical health; history of psychiatric difficulties was a risk factor for impaired mental health. Education, older donation age and a first‐degree relation to the recipient were protective factors. One percent reported that donation affected their health very negatively. Enhanced predonation evaluation and counseling may be warranted, along with ongoing monitoring for overweight donors. Questionnaires completed by 2544 living donors 5 to 48 years postnephrectomy show that 80% have average or better health‐related quality of life for their age and sex based on SF‐36 norms and that obesity, history of psychiatric difficulties and nonwhite race are risk factors for poor health‐related quality of life outcomes, whereas being older, having more education and/or being a first‐degree relation to the recipient predict better outcomes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/100300/1/ajt12434.pd

Emotional Well‐Being of Living Kidney Donors: Findings From the RELIVE Study

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109345/1/ajt12906.pd

Glycolate Oxidase Isozymes Are Coordinately Controlled by GLO1 and GLO4 in Rice

Glycolate oxidase (GLO) is a key enzyme in photorespiratory metabolism. Four putative GLO genes were identified in the rice genome, but how each gene member contributes to GLO activities, particularly to its isozyme profile, is not well understood. In this study, we analyzed how each gene plays a role in isozyme formation and enzymatic activities in both yeast cells and rice tissues. Five GLO isozymes were detected in rice leaves. GLO1 and GLO4 are predominately expressed in rice leaves, while GLO3 and GLO5 are mainly expressed in the root. Enzymatic assays showed that all yeast-expressed GLO members except GLO5 have enzymatic activities. Further analyses suggested that GLO1, GLO3 and GLO4 interacted with each other, but no interactions were observed for GLO5. GLO1/GLO4 co-expressed in yeast exhibited the same isozyme pattern as that from rice leaves. When either GLO1 or GLO4 was silenced, expressions of both genes were simultaneously suppressed and most of the GLO activities were lost, and consistent with this observation, little GLO isozyme protein was detected in the silenced plants. In contrast, no observable effect was detected when GLO3 was suppressed. Comparative analyses between the GLO isoforms expressed in yeast and the isozymes from rice leaves indicated that two of the five isozymes are homo-oligomers composed of either GLO1 or GLO4, and the other three are hetero-oligomers composed of both GLO1 and GLO4. Our current data suggest that GLO isozymes are coordinately controlled by GLO1 and GLO4 in rice, and the existence of GLO isozymes and GLO molecular and compositional complexities implicate potential novel roles for GLO in plants

Age-Related Impairment of Ultrasonic Vocalization in Tau.P301L Mice: Possible Implication for Progressive Language Disorders

Tauopathies, including Alzheimer's Disease, are the most frequent neurodegenerative diseases in elderly people and cause various cognitive, behavioural and motor defects, but also progressive language disorders. For communication and social interactions, mice produce ultrasonic vocalization (USV) via expiratory airflow through the larynx. We examined USV of Tau.P301L mice, a mouse model for tauopathy expressing human mutant tau protein and developing cognitive, motor and upper airway defects.At age 4-5 months, Tau.P301L mice had normal USV, normal expiratory airflow and no brainstem tauopathy. At age 8-10 months, Tau.P301L mice presented impaired USV, reduced expiratory airflow and severe tauopathy in the periaqueductal gray, Kolliker-Fuse and retroambiguus nuclei. Tauopathy in these nuclei that control upper airway function and vocalization correlates well with the USV impairment of old Tau.P301L mice.In a mouse model for tauopathy, we report for the first time an age-related impairment of USV that correlates with tauopathy in midbrain and brainstem areas controlling vocalization. The vocalization disorder of old Tau.P301L mice could be, at least in part, reminiscent of language disorders of elderly suffering tauopathy