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The notch stress intensity factor (N-SIF) is widely used to characterize the notch stress concentration under different crack opening angles. At present, the evaluation formula of notch stress intensity factor is too complicated and inconvenient for engineering applications. Therefore, based on the isotropic V-notch plate, this paper introduces the concept of singular strength factor a s i , and further presents the notch stress field and the simple evaluation formula of N-SIF for double edge V-notched orthotropic thin plate. The formula is simple in form and clear in physical meaning. After numerical verification and verification with the evaluation results of traditional literature, the results show that the semi-analytical formula proposed in this paper has a wider application range and can be applied to different materials and loads simultaneously. [ABSTRACT FROM AUTHOR]

Background: Reproductive and menstrual factors have been evaluated as surrogates for long-term hormonal exposures in several prospective studies of colorectal cancer, yet findings have been conflicting.Methods: The relation of reproductive and menstrual factors (self-reported via a reproductive history questionnaire) with incident colorectal cancer was investigated among women enrolled in the Women's Health Initiative Observational Study (WHI-OS), a longitudinal cohort of 93 676 postmenopausal women (aged 50-79 years at enrolment) in which 1149 incident cases of colorectal cancer occurred over a median follow-up of 11.9 years. Multivariable Cox proportional hazards models that included established colorectal cancer risk factors were constructed to examine the association of colorectal cancer incidence with reproductive and menstrual factors.Results: Having had two children (vs nulliparous: hazard ratio (HR)=0.80, 95% confidence interval (CI): 0.64-0.99) was inversely associated with colorectal cancer risk. Compared with never users, ever use of oral contraceptives was associated with lower colorectal cancer risk (HR=0.74, 95% CI: 0.63-0.86); however, no relationship was observed for duration of oral contraceptives use (4 years vs 1 year: HR=0.94, 95% CI: 0.67-1.32). None of the remaining reproductive and menstrual factors was associated with colorectal cancer incidence.Conclusions: Parity and prior use of oral contraceptives were associated with lower colorectal cancer risk in this cohort of postmenopausal women. [ABSTRACT FROM AUTHOR]

To examine the association between actual and perceived overweight/obese status and excess gestational weight gain (GWG). As part of an infant feeding trial, multi-ethnic lower and moderate income women-completed a checklist of current health conditions, including “overweight/obesity,” “asthma,” and “hypertension” while pregnant. Odds of excessive GWG per the Institute of Medicine guidelines in ‘accurate’ versus ‘inaccurate’ reporters, by overweight status were analyzed with multivariate logistic regression for women with pre-or early pregnancy BMIs of ≥18.5. 775 women met study criteria. Just 21 % (n = 107) of overweight/obese women accurately identified their weight status, compared to >90 % accurate report of documented hypertension or asthma. Compared to normal-weight accurate reporters, the adjusted odds of excessive GWG in overweight/obese women was 2.3 (95 % CI 1.4, 3.7) in accurate reporters, and 2.5 (95 % CI 1.7, 3.4) in inaccurate reporters. Overweight/obesity is associated with excessive GWG, but this risk is not modified by inaccurate reporting/perception of weight-status. [ABSTRACT FROM AUTHOR]