in this paper, we consider an  i.e., multiple step-stress accelerated life testing (alt) experiment with unequal duration of time . it is assumed that the time to failure of a product follows rayleigh distribution with a log-linear relationship between stress and lifetime and also we assume a generalized khamis-higgins model for the effect of changing stress levels. taking into account that the...

In this paper, we consider an  i.e., multiple step-stress accelerated life testing (ALT) experiment with unequal duration of time . It is assumed that the time to failure of a product follows Rayleigh distribution with a log-linear relationship between stress and lifetime and also we assume a generalized Khamis-Higgins model for the effect of changing stress levels. Taking into account that the...

Hutchinson-Gilford progeria syndrome is an extremely rare condition with features of premature and accelerated aging. The pattern of inheritance is unclear, although autosomal dominant mutations have been proposed. The disease presentation is usually in infancy and early childhood with a characteristic phenotype of short stature, abnormal skin and nail, beaked nose, loss of subcutaneous f...

We report a case of a 23-year-old Japanese woman who had severe hyperparathyroidism associated with chronic renal failure before the start of dialysis treatment. Her chief complaints were swelling and pain in both shoulders. Laboratory examination revealed renal failure (BUN 134 mg/dl, serum Cr 7.3 mg/dl), severe normocytic normochromic anemia (hemoglobin 4.3 g/dl), hypercalcemia (11.8 mg/dl), ...

We recently developed a mouse model with a single functional allele of Serca2 (Serca2+/-) that shows impaired cardiac contractility and relaxation without overt heart disease. The goal of this study was to test the hypothesis that chronic reduction in sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA)2 levels in combination with an increased hemodynamic load will result in an accelerated pathwa...

The concept of accelerated testing by tracking degradation of samples over test time needs to be developed for reliability estimation. This paper aims at proposing practical approaches to conduct accelerated degradation testing on new and available used samples. For this purpose, product failure is related to a suitable physical property. Then, its failure time is defined as the expected time i...

Renal cell carcinoma (RCC) is often detected incidentally and early. Currently, open partial nephrectomy and laparoscopic total nephrectomy form competing technologies. The former is invasive, but nephron-sparing; the other is considered less invasive but with more loss of renal mass. Traditionally, emphasis has been placed on oncologic outcomes. However, a patient with an excellent oncologic o...

The Cox proportional hazards model has become the model of choice to use in analyzing the effects of covariates on survival data. However, this assumption has significant restrictions on the behavior of the conditional survival function. The accelerated failure time model, which models the survival time and covariates directly through regression, provides an alternative approach to interpret th...

In this article, we estimate accelerated time-to-failure and proportional-hazard functions with about 100,000 members of the Dorn sample, finding greater hazards associated with smoking and some dependence on occupational variables that measure risk and physical activity. We answer three questions: (1) How sensitive are the estimates to sample length, using monthly data for the periods 1954-196...