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Dental biomechanics based on finite element (FE) analysis is attracting enormous interest in dentistry, biology, anthropology and palaeontology. Nonetheless, several shortcomings in FE modeling exist, mainly due to unrealistic loading conditions. In this contribution we used kinematics information recorded in a virtual environment derived from occlusal contact detection between high resolution models of an upper and lower human first molar pair (M1 and M1, respectively) to run a non-linear dynamic FE crash colliding test.MicroCT image data of a modern human skull were segmented to reconstruct digital models of the antagonistic right M1 and M1 and the dental supporting structures. We used the Occlusal Fingerprint Analyser software to reconstruct the individual occlusal pathway trajectory during the power stroke of the chewing cycle, which was applied in a FE simulation to guide the M1 3D-path for the crash colliding test.FE analysis results showed that the stress pattern changes considerably during the power stroke, demonstrating that knowledge about chewing kinematics in conjunction with a morphologically detailed FE model is crucial for understanding tooth form and function under physiological conditions.Results from such advanced dynamic approaches will be applicable to evaluate and avoid mechanical failure in prosthodontics/endodontic treatments, and to test material behavior for modern tooth restoration in dentistry. This approach will also allow us to improve our knowledge in chewing-related biomechanics for functional diagnosis and therapy, and it will help paleoanthropologists to illuminate dental adaptive processes and morphological modifications in human evolution.

Expanding anthropogenic activities, globally and in Egypt, have increased concentrations of heavy metals in surface and ground waters. Contamination of drinking water may threaten public health. In the present study, the concentrations of 10 heavy metals were analyzed from natural springs (6) and drilled wells (10) in the Nubian Sandstone Aquifer of the El-Farafra Oasis and the White Desert National Park, Egypt. The average concentrations of heavy metals were in most cases below critical values of the WHO drinking water standard, except for Fe and Mn (average values were 495 and 107 µg·L−1, respectively). There is a surface circulation that develops within limestone (Post-Nubian Aquifer System—PNAS) and feeds the springs, while the water present in the wells (at least for the deeper ones) comes from the ferruginous sandstone (Nubian Sandstone Aquifer System—NSAS). This double circulation could account for the differences in the EC and TDS values (typical of a circulation in limestone-type aquifers for springs) and the Fe and Mn enrichment coming from the ferruginous sandstone of the NSAS. The average chronic daily intake (CDI) values for heavy metals in the study area are listed in decreasing order in the following: Fe > Mn > Zn > Co > Ni > Cr > As > Pb > Co > Cd. The total hazard quotient (HQtotal = HQoral + HQdermal) and Hazard Index (HI) values calculated for different heavy metals were well below the acceptable limit, indicating no significant non-carcinogenic health risks to the residents of both areas via oral and dermal absorption of drinking water. Furthermore, the results obtained for the total risk to human health showed that oral ingestion is the major pathway. Carcinogenic risk analysis indicated that the Incremental Lifetime Cancer Risk (ILCR) values for Pb, Cd, Ni, and Cr were well below the acceptable limits.

Using combined individual patient data from prospective studies, we explored sex differences in depression and prognosis post-myocardial infarction (MI) and determined whether disease indices could account for found differences.Individual patient data analysis of 10,175 MI patients who completed diagnostic interviews or depression questionnaires from 16 prospective studies from the MINDMAPS study was conducted. Multilevel logistic and Cox regression models were used to determine sex differences in prevalence of depression and sex-specific effects of depression on subsequent outcomes.Combined interview and questionnaire data from observational studies showed that 36% (635/1760) of women and 29% (1575/5526) of men reported elevated levels of depression (age-adjusted odds ratio = 0.68, 95% confidence interval [CI] = 0.60-0.77). The risk for all-cause mortality associated with depression was higher in men (hazard ratio = 1.38, 95% CI = 1.30-1.47) than in women (hazard ratio = 1.22, 95% CI = 1.14-1.31; sex by depression interaction: p.001). Low left ventricular ejection fraction (LVEF) was associated with higher depression scores in men only (sex by LVEF interaction: B = 0.294, 95% CI = 0.090-0.498), which attenuated the sex difference in the association between depression and prognosis.The prevalence of depression post-MI was higher in women than in men, but the association between depression and cardiac prognosis was worse for men. LVEF was associated with depression in men only and accounted for the increased risk of all-cause mortality in depressed men versus women, suggesting that depression in men post-MI may, in part, reflect cardiovascular disease severity.