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This study addresses the critical need for a constitutive model to analyze the cyclic plasticity of additively manufactured 316L stainless steel. The anisotropic behavior at both room temperature and 300 °C is investigated experimentally based on cyclic hysteresis loops performed in different orientations with respect to the build direction. A comprehensive constitutive model is proposed, that integrates the Armstrong-Frederick nonlinear kinematic hardening, Voce nonlinear isotropic hardening and Hill's anisotropic yield criterion within a 3D return mapping algorithm. The model was calibrated to specimens in the 0° and 90° orientations and validated with specimens in the 45° orientation. A single set of hardening parameters successfully represented the elastoplastic response for all orientations at room temperature. The algorithm effectively captured the full cyclic hysteresis loops, including historical effects observed in experimental tests. A consistent trend of reduced hardening was observed at elevated temperature, while the 45° specimen orientation consistently exhibited the highest degree of strain hardening. The applicability of the model was demonstrated by computing energy dissipation for stabilized hysteresis loops, which was combined with fatigue tests to propose an energy-based fatigue life prediction model., QC 20240514

The process of an unstable plastic flow associated with the strain rate sensitivity of mechanical properties was studied in porous 316L austenitic steel samples manufactured by laser powder bed fusion (L-PBF). Different micromechanisms of deformation and fracture of porous samples dependent on strain rate were found. It was found that despite the porosity, the specimens showed high strength, which increased with the loading rate. Porosity led to lower ductility of the studied specimens, in comparison with literature data for low porous 316L L-PBF samples and resulted in de-localization of plastic deformation. With an increase in strain rate, nucleation of new pores was less pronounced, so that at the highest strain rate of 8 × 10-3s-1, only pore coalescence was ob-served as the dominating microscopic mechanism of ductile fracture. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Background: Psychosocial stress and depression are established risk factors for cardiovascular disease and a relationship to periodontitis has been suggested. We studied symptoms of depression and their relation to myocardial infarction and periodontitis. Methods: In a Swedish case-control study, 805 patients, <75 years with a first myocardial infarction and 805 controls without myocardial infarction were matched for age, gender and geographic area. Mean age was 62±8 years and 81% were male. Standardised physical examination and dental panoramic X-ray for grading of periodontal status was performed. Medical history including risk factors related to cardiovascular disease and periodontitis was collected as was detailed information on perceived stress at home and work, and symptoms of depression (Montgomery Åsberg Depression Scale). A Montgomery Åsberg Depression Scale score ≥13 was considered clinically relevant. Results: A family history of cardiovascular disease, smoking and divorce was more frequent among patients than controls. Patients had more symptoms of depression than controls (14 vs 7%; p<0.001) but received less anti-depressive treatment (16 vs 42%; p<0.001). Symptoms of depression doubled the risk for myocardial infarction (Montgomery Åsberg Depression Scale: odds ratio 2.17 (95% confidence interval 1.41-3.34)). There was no difference in symptoms of depression between study participants with and without periodontitis. Conclusion: Patients with a first myocardial infarction were more frequently depressed than matched controls without myocardial infarction, but received less anti-depressive treatment. A relationship between depression and periodontitis could not be confirmed., QC 20170818

QCR 20190612

Background: High suicide intent, childhood trauma, and violent behavior are risk factors for suicide in suicide attempters. The aim of this study was to investigate whether the combined assessment of suicide intent and interpersonal violence would provide a better prediction of suicide risk than an assessment of only suicide intent or interpersonal violence. Methods: This is a cohort study involving 81 suicide attempters included in the study between 1993 and 1998. Patients were assessed with both the Suicide Intent Scale (SIS) and the Karolinska Interpersonal Violence Scale (KIVS). Through the unique personal identification number in Sweden, patients were linked to the Cause of Death Register maintained by the Swedish National Board of Health and Welfare. Suicides were ascertained from the death certificates. Results: Seven of 14 patients who had died before April 2013 had committed suicide. The positive predictive value for the Suicide Intent Scale alone was 16.7 %, with a specificity of 52 % and an area under the curve of 0.74. A combined assessment with the KIVS gave higher specificity (63 %) and a positive predictive value of 18.8 % with an AUC of 0.83. Combined use of SIS and KIVS expressed interpersonal violence as an adult subscale gave a sensitivity of 83.3 %, a specificity of 80.3 %, and a positive predictive value of 26 % with an AUC of 0.85. The correlation between KIVS and SIS scores was not significant. Conclusions: Using both the the SIS and the KIVS combined may be better for predicting completed suicide than using them separately. The nonsignificant correlation between the scales indicates that they measure different components of suicide risk.

BACKGROUND: Prolonged psychosocial stress is a condition assessed through self-reports. Here we aimed to identify biochemical markers for screening and early intervention in women. METHODS: Plasma concentrations of interleukin (IL) 1-alpha, IL1-beta, IL-2, IL-4, IL-6, IL-8, IL-10, interferon-gamma (INF-gamma), tumor necrosis factor-alpha (TNF-alpha), monocyte chemotactic protein-1 (MCP-1), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), thyroid stimulating hormone (TSH), total tri-iodothyronine (TT3), total thyroxine (TT4), prolactin, and testosterone were measured in: 195 women on long-term sick-leave for a stress-related affective disorder, 45 women at risk for professional burnout, and 84 healthy women. RESULTS: We found significantly increased levels of MCP-1, VEGF and EGF in women exposed to prolonged psychosocial stress. Statistical analysis indicates that they independently associate with a significant risk for being classified as ill. CONCLUSIONS: MCP-1, EGF, and VEGF are potential markers for screening and early intervention in women under prolonged psychosocial stress., QC 20120216

Context: Capsulotomy is sometimes used as a treatment of last resort in severe and treatment refractory cases of Obsessive-Compulsive Disorder (OCD). Objective: To evaluate the long-term efficacy and safety of capsulotomy in OCD. Design: Non-controlled long-term follow-up trial (mean 10.9 years after surgery). Setting: University hospital referral center. Patients: 25 consecutive OCD patients having undergone capsulotomy between the years 1988 and 2000. Intervention: Unilateral or bilateral capsulotomy. Lesions were created either by conventional heating or by gamma-radiation (radiosurgery). Main Outcome Measure: Yale-Brown Obsessive-Compulsive Rating Scale (Y-BOCS). Results: Mean Y-BOCS was 34 preoperatively and dropped to 18 at long-term follow-up (p<0.0001). Response (defined as ≥ 35 % reduction at long-term compared to baseline) was seen in 12 patients at long-term. Eight patients were in remission (Y-BOCS < 16) at long-term follow-up. Response rates did not differ between surgical method. A mean weight gain of 6 kg was reported in the first postoperative year. Ten patients were considered to sufferer from significant problems in the area of executive functioning, apathy or disinhibition. Six of these ten patients had either had high doses of radiation or multiple surgical procedures. Our MRI analysis of 11 patients suggests that the OCD symptom reduction may be increased by reducing the lateral extension of the lesions, and a reduction in the medial and posterior extension may limit the risk of side effects, that is, smaller lesions may produce better results. Conclusions: Capsulotomy is effective in reducing OCD symptoms. There is a substantial risk of side effects and the risk may vary between surgical methods. Our findings suggest that smaller lesions are safer and that high radiation doses and multiple procedures should be avoided., VR-Neuroscience