Finite element simulation of semi-finishing turning of Electron Beam Melted Ti6Al4V under dry and cryogenic cooling

open6noIn the last few years, important step forwards have been made on Finite Element Simulation of machining operations. Wrought Ti6Al4V alloy has been deeply investigated both numerically and experimentally due to its wide application in the industry. Recently, Additive Manufacturing technologies as the Electron Beam Melting and the Direct Melting Laser Sintering are more and more employed in the production of biomedical and aeronautical components made of Ti6Al4V alloy. Fine acicular microstructures are generated by the application of additive manufacturing technologies, affecting the mechanical properties and the machinability. By the consequence, this peculiarity has to be considered in modelling the material behaviour. In this work, a numerical analysis of cylindrical external turning on Electron Beam Melted (EBM) Ti6Al4V alloy is presented. A Johnson-Cook constitutive equation was implemented as a flow stress model and adapted with respect to the wrought Ti6Al4V alloy. The model was calibrated and validated through the cutting forces and temperatures measurements acquired under dry and cryogenic lubricating conditions.openBordin, A; Imbrogno, S.; Rotella, G.; Bruschi, S.; Ghiotti, A.; Umbrello, D.Bordin, Alberto; Imbrogno, S.; Rotella, G.; Bruschi, Stefania; Ghiotti, Andrea; Umbrello, D

Exposição à violência entre jovens da cidade de São Paulo em privação de liberdade

OBJECTIVE: This study aimed to determine the extent of exposure to community violence among delinquent Brazilian youth in the 12-month period prior to their incarceration and to identify factors associated with this exposure. METHOD: With an oversampling of girls, a cross-section of youth under 18 years of age from juvenile detention units in the city of São Paulo, Brazil completed a structured interview. Key items related to exposure to violence (witnessed and experienced) were drawn from the Social and Health Assessment questionnaire to cover the 12-month period prior to incarceration. RESULTS: Participants (n = 325, 89% boys) reported high rates of exposure to violence with largely similar levels for boys and girls. Being threatened with physical harm, being beaten or mugged and/ or shot at were the most common forms of violence experienced. After controlling for demographic and family variables, the fact of having peers involved in risk behavior, easy access to guns and previous involvement with the justice system were associated with witnessed violence; whereas having slept on the street was the only variable associated with experienced violence. CONCLUSION: This group of youth was exposed to high levels of violence and other adverse experiences. Future research should examine the effectiveness of strategies aimed at reducing the exposure to violence of high-risk youth.OBJETIVO: Esse estudo procurou determinar a extensão da exposição à violência na comunidade entre jovens brasileiros delinquentes nos 12 meses que antecederam sua privação de liberdade e identificar fatores associados a essa exposição. MÉTODO: Um corte transversal de menores de 18 anos internados em unidades da Fundação Casa/ex-FEBEM na cidade de São Paulo, Brasil (com meninas superamostradas) participou de entrevista estruturada. Itens-chave sobre exposição à violência (testemunhada e vivenciada) foram retirados do questionário Social and Health Assessment para cobrir o período de 12 meses anterior à internação. RESULTADOS: Os participantes (n = 325, 89% meninos) referiram altas taxas de exposição à violência, taxas estas muito similares entre meninos e meninas. Ter sofrido ameaças de lesão física, ter sido espancado ou assaltado e/ou baleado foram as formas mais comuns de violência vivenciada. Após controlar por fatores sociodemográficos e familiares, o relacionamento com jovens envolvidos em comportamentos de risco, o fácil acesso a armas de fogo e a passagem prévia pela Justiça estiveram associados à violência testemunhada, enquanto ter dormido na rua foi o único fator associado à violência vivenciada. CONCLUSÃO: Esse grupo de jovens foi exposto a altos níveis de violência e a outras experiências adversas. Pesquisas futuras devem examinar a efetividade de estratégias que visem reduzir a exposição à violência entre jovens de alto risco.University of Calgary Faculty of Medicine Department of Community Health SciencesUniversity of Calgary Faculty of Medicine Departments of Community Health Sciences, Psychiatry and PediatricsUniversidade Federal de São Paulo (UNIFESP) Departamento de PsiquiatriaUNIFESP, Depto. de PsiquiatriaSciEL

TrajPy: empowering feature engineering for trajectory analysis across domains

Trajectories, sequentially measured quantities that form a path, are an important presence in many different fields, from hadronic beams in physics to electrocardiograms in medicine. Trajectory anal-ysis requires the quantification and classification of curves either using statistical descriptors or physics-based features. To date, there is no extensive and user-friendly package for trajectory anal-ysis available, despite its importance and potential application across domains. We developed a free open-source python package named TrajPy as a complementary tool to empower trajectory analysis. The package showcases a friendly graphic user interface and provides a set of physical descriptors that help characterizing these intricate structures. In combina-tion with image analysis, it was already successfully applied to the study of mitochondrial motility in neuroblastoma cell lines and to the analysis of in silico models for cell migration. The TrajPy package was developed in Python 3 and released under the GNU GPL-3 license. Easy installation is available through PyPi and the development source code can be found in the repository https://github.com/ocbe-uio/TrajPy/. The package release is automatically archived under the DOI 10.5281/zenodo.3656044.Comment: 4 pages, 1 figur

Does traumatic occlusal forces lead to peri-implant bone loss? a systematic review

Observational studies have indicated that crestal bone level changes at implants are typically associated with clinical signs of inflammation, but still mechanical overload has been described as possible factor leading to hard-tissue deficiencies at implant sites without mucosal inflammation. The aim of this paper was systematically review the literature regarding the possible effect of traumatic occlusal forces on the peri-implant bone levels. Literature search was conducted using PubMed, Scielo and Lilacs, including the following terms: oral OR dental AND implant$AND (load OR overload OR excessive load OR force$ OR bruxism) AND (bone loss OR bone resorption OR implant failure$). Databases were searched for the past 10 years of publications, including: clinical human studies, either randomized or not, cohort studies, case control studies, case series and animal research. Exclusion criteria were review articles, guidelines and in vitro and in silico (finite element analysis) research, as well as retrospective studies. The PICO questions formulated was: "does traumatic occlusal forces lead to peri-implant bone loss?" The database searches as well as additional hand searching, resulted in 807 potentially relevant titles. After inclusion/exclusion criteria assessment 2 clinical and 4 animal studies were considered relevant to the topic. The included animal studies did not reveal an association between overload and peri-implant bone loss when lower overloads were applied, whereas in the presence of excessive overload it seemed to generate peri-implant bone loss, even in the absence of inflammation. The effect of traumatic occlusal forces in peri-implant bone loss is poorly reported and provides little evidence to support a cause-and-effect relationship in humans, considering the strength of a clinically relevant traumatic occlusal force33

Interactional positioning and narrative self-construction in the first session of psychodynamic-interpersonal psychotherapy

The purpose of this study is to identify possible session one indicators of end of treatment psychotherapy outcome using the framework of three types of interactional positioning; client’s self-positioning, client’s positioning between narrated self and different partners, and the positioning between client and therapist. Three successful cases of 8-session psychodynamic-interpersonal (PI) therapy were selected on the basis of client Beck Depression Inventory scores. One unsuccessful case was also selected against which identified patterns could be tested. The successful clients were more descriptive about their problems and demonstrated active rapport-building, while the therapist used positionings expressed by the client in order to explore the positionings developed between them during therapy. The unsuccessful case was characterized by lack of positive self-comment, minimization of agentic self-capacity, and empathy-disrupting narrative confusions. We conclude that the theory of interactional positioning has been useful in identifying patterns worth exploring as early indicators of success in PI therapy

Human neutrophil alloantigens systems

Neutrophil alloantigens are involved in a variety of clinical conditions including immune neutropenias, transfusion-related acute lung injury (TRALI), refractoriness to granulocyte transfusions and febrile transfusion reactions. In the last decade, considerable progress has been made in the characterization of the implicated antigens. Currently, seven antigens are assigned to five human neutrophil antigen (HNA) systems. The HNA-1a, HNA-1b and HNA-1c antigens have been identified as polymorphic forms of the neutrophil Fcγ receptor IIIb (CD16b), encoded by three alleles. Recently, the primary structure of the HNA-2a antigen was elucidated and the HNA-2a-bearing glycoprotein was identified as a member of the Ly-6/uPAR superfamily, which has been clustered as CD177. The HNA-3a antigen is located on a 70-95 kDa glycoprotein; however, its molecular basis is still unknown. Finally, the HNA-4a and HNA-5a antigens were found to be caused by single nucleotide mutations in the αM (CD11b) and αL (CD11a) subunits of the leucocyte adhesion molecules (β2 integrins). Molecular and biochemical characterization of neutrophil antigenshave expanded our diagnostic tools by the introduction of genotyping techniques and immunoassays for antibody identification. Further studies in the field of neutrophil immunology will facilitate the prevention and management of transfusion reactions and immune diseases caused by neutrophil antibodies.Os aloantígenos de neutrófilos estão associados a várias condições clínicas como neutropenias imunes, insuficiência pulmonar relacionada à transfusão (TRALI), refratariedade à transfusão de granulócitos, e reações transfusionais febris. Na última década, foi observado considerável progresso na caracterização dos aloantígenos envolvidos nestas condições clínicas. Atualmente sete antígenos estão incluídos em cinco sistemas de antígenos de neutrófilo humano (HNA). Os antígenos HNA-1a, HNA-1b e HNA-1c foram identificados como formas polimórficas do receptor Fcγ RIIIb (CD16b), codificados por três alelos. Recentemente, a estrutura primária do antígeno HNA-2a foi elucidada e a glicoproteína carreadora do antígeno foi identificada como um membro da superfamília Ly-6/uPARe designada como CD177. O antígeno HNA-3a está localizadoem uma glicoproteína de 70-90 kDa, entretanto sua base molecular ainda é desconhecida. Finalmente, os antígenos HNA-4ae HNA-5a são resultantes de mutações de um único nucleotídeo nas subunidades αM (CD11b) and αL (CD11a) das moléculas de adesão de leucócitos (β2 integrinas). A caracterização molecular e bioquímica dos antígenos neutrofílicos permitiu a expansão das ferramentas diagnósticas pela introdução de técnicas de genotipagem e imunoensaios para a identificação de anticorpos. Novos estudos envolvendo a imunologia de granulócitos serão de grande valor para a prevenção e tratamento de reações transfusionais e doenças imunes causadas por aloanticorpos de neutrófilos.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo (UNIFESP)UNIFESPSciEL

Crossed Andreev reflection and elastic co-tunneling in a three-site Kitaev chain nanowire device

The formation of a topological superconducting phase in a quantum-dot-based Kitaev chain requires nearest neighbor crossed Andreev reflection and elastic co-tunneling. Here we report on a hybrid InSb nanowire in a three-site Kitaev chain geometry - the smallest system with well-defined bulk and edge - where two superconductor-semiconductor hybrids separate three quantum dots. We demonstrate pairwise crossed Andreev reflection and elastic co-tunneling between both pairs of neighboring dots and show sequential tunneling processes involving all three quantum dots. These results are the next step towards the realization of topological superconductivity in long Kitaev chain devices with many coupled quantum dots

Structure and dynamics of nanoconfined water and aqueous solutions

This review is devoted to discussing recent progress on the structure, thermodynamic, reactivity, and dynamics of water and aqueous systems confined within different types of nanopores, synthetic and biological. Currently, this is a branch of water science that has attracted enormous attention of researchers from different fields interested to extend the understanding of the anomalous properties of bulk water to the nanoscopic domain. From a fundamental perspective, the interactions of water and solutes with a confining surface dramatically modify the liquid's structure and, consequently, both its thermodynamical and dynamical behaviors, breaking the validity of the classical thermodynamic and phenomenological description of the transport properties of aqueous systems. Additionally, man-made nanopores and porous materials have emerged as promising solutions to challenging problems such as water purification, biosensing, nanofluidic logic and gating, and energy storage and conversion, while aquaporin, ion channels, and nuclear pore complex nanopores regulate many biological functions such as the conduction of water, the generation of action potentials, and the storage of genetic material. In this work, the more recent experimental and molecular simulations advances in this exciting and rapidly evolving field will be reported and critically discussed

Features of the Parameters of 24-Hours pH-Impedance and High-Resolution Esophageal Manometry in Patients with Barrett's Esophagus on Proton Pump Inhibitors

Аim: to identify predictors of insufficient effectiveness of proton pump inhibitors based on the evaluation of the results of 24-hour pH-impedance and high-resolution esophageal manometry in patients with Barrett's esophagus.Materials and methods. 52 patients with histologically confirmed Barrett's esophagus who are on therapy with proton pump inhibitors were examined. All patients underwent daily pH-impedance and high-resolution esophageal manometry.Results. According to daily pH-impedance, group 1 consisted of 37 patients who responded satisfactorily to antisecretory therapy, group 2 of 15 patients who demonstrated insufficient response to acid-suppressive therapy, 11 of whom had no clinical manifestations. The total number of reflux averaged 55 in group 1 and 106 in group 2. The average number of acid reflux in group 1 was 5.68, in group 2 — 48.5. The average number of non-acid reflux prevailed in patients of group 2 and averaged 58, in group 1 the indicator averaged 47. Evaluation of the results of high-resolution esophageal manometry showed that violations of the structure and function of the esophago-gastric junction were detected in 21 patients out of 52. Disorders of the motility of the thoracic esophagus were detected in 31 patients out of 52. When comparing the frequency of motor disorders from the thoracic esophagus in groups 1 and 2, no significant differences were obtained. However, significantly more frequent registration of violations of the structure and/or function of the esophago-gastric junction was found in the group with unsatisfactory effectiveness of proton pump inhibitors.Conclusion. In a number of patients with Barrett's esophagus, there is an insufficient effect of acid-suppressive therapy and at the same time an asymptomatic course of the disease, which may increase the risk of its progression. Predictors of insufficiently successful treatment of patients with Barrett's esophagus may be both insufficient pharmacological effect of proton pump inhibitors themselves, and motility disorders that cause the presence of non-acid reflux, decreased esophageal clearance, which in turn may cause the patient's symptoms to persist and adversely affect the condition of the esophageal mucosa

Inositol administration reduces oxidative stress in erythrocytes of patients with polycistic ovary syndrome.

OBJECTIVE: Possibly due to a deficiency of insulin mediators, polycystic ovary syndrome (PCOS) is often associated with insulin resistance (IR) and hyperinsulinemia, likely responsible for an elevated production of reactive oxygen species. We investigated oxidative-related alterations in erythrocytes and anti-inflammatory effects of inositol in women with PCOS before and after treatment with myo-inositol (MYO). METHODS: Twenty-six normal-weight PCOS patients were investigated before and after MYO administration (1200 mg/day for 12 weeks; n=18) or placebo (n=8) by evaluating serum testosterone, serum androstenedione, fasting serum insulin, fasting serum glucose, insulin area under the curve (AUC), and glucose AUC after oral glucose tolerance test and homeostasis model of assessment-IR. In erythrocytes, band 3 tyrosine phosphorylation (Tyr-P) level, glutathione (GSH) content, and glutathionylated proteins (GSSP) were also assessed. RESULTS: Data show that PCOS patients' erythrocytes underwent oxidative stress as indicated by band 3 Tyr-P values, reduced cytosolic GSH content, and increased membrane protein glutathionylation. MYO treatment significantly improved metabolic and biochemical parameters. Significant reductions were found in IR and serum values of androstenedione and testosterone. A significant association between band 3 Tyr-P levels and insulin AUC was found at baseline but disappeared after MYO treatment, while a correlation between band 3 Tyr-P and testosterone levels was detected both before and after MYO treatment. CONCLUSIONS: PCOS patients suffer from a systemic inflammatory status that induces erythrocyte membrane alterations. Treatment with MYO is effective in reducing hormonal, metabolic, and oxidative abnormalities in PCOS patients by improving IR