Evolution of prototyping in automotive engineering: a comprehensive study on the reliability of Additive Manufacturing for advanced powertrain components

Additive manufacturing (AM) could be used to reduce the production times of prototypes; however, further research is required to address metals structural parts. To obtain the correct properties, some relevant factors to be considered are the build volume, shape factor, and the need for specific heat treatments. This study aims to evaluate the reliability of AM prototypes applied at a new powertrain system developed to reduce vehicle emissions. Firstly, it was investigated the mechanical behavior, microstructure, and the effect of sample size and heat treatments on both specimens and prototypes made of AM 17-4PH steel. Finite Element Analysis (FEA) was performed to evaluate the structural resistance. Finally, the prototypes were produced, analyzed, and tested on a functional engine test bench to evaluate their reliability. The mechanical properties decreased with an increase in the sample volume. After heat treatment, the yield strength increased, due to the transformation of δ-ferrite in martensite and the reduction of retained austenite. The engine test bench was successfully completed. The conclusions set the basis for similar future applications of time-effective prototypes that can be dimensioned owing to appositely developed postprocesses that guarantee the required resistance

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Summary: Diabetic mastopathy (MD) was described for the first time in 1984 by Soler and Khardori, in insulin-dependent patients with type I diabetes, representing 1% of benign mastopathy. The clinical-imaging presentation raises carcinomas or benign lesions such as fibroadenomas as the main differential diagnoses, for which excisional biopsy is the treatment of choice. The communication of this case aims to highlight the importance of the differential diagnosis of this low incidence breast disease entity whose etiology is systemic. This is a 45-year-old patient, native from Córdoba capital, taxi driver, with a toxic history of smoking and alcoholism; Personal pathological history of type I diabetes treated with NPH insulin and good glycemic controls. She consulted due to the presentation of a right breast phlogotic erythematous tumor of 40 days of evolution. She had undergone antibiotic treatment for two weeks, without obtaining a response. A mammogram was performed in the right breast, finding a radiopaque area with diffuse lobulated edges that caused retraction of the nipple and frank skin thickening, with a proliferative appearance (BIRADS classification V). An incisional biopsy and drainage are performed, indicating hospitalization and combined antibiotic treatment (clindamycin + gentamicin). It evolves favorably and subsequently a pathological anatomy report is received. In the macroscopy, four irregularly shaped tissue fragments of approximately 2x1 cm are observed, which present a whitish color and firm consistency in the cut. Histopathology reports slices processed with standard techniques and stained with H-E exhibiting in the breast tissue dense stroma, prominent hyaline bundles of collagen, blood vessels with thickened hyaline walls, which produce lumen stenosis. There is an important mononuclear inflammatory infiltrate, neutrophil polymorphonuclear leukocytes and histiocytes, ducts with epithelial cells reactive to the inflammatory process, and areas of necrosis and skin with polymorphonuclear leukocytes in transepithelial migration. This findings described are linked to diabetic mastopathy / acute nonspecific mastitis. The clinical case, highlights the fact that when we are faced with a clinical-imaging lesion suggestive of malignancy, it is essential to always consider the clinical context, because despite its low prevalence, DM is an entity to consider, especially in patients with a history of type diabetes I.Resumen:  La mastopatía diabética (MD) fue descripta por primera vez en 1984 por Soler y Khardori, en pacientes insulinodependientes con diabetes tipo I, representando el 1% de la mastopatía benigna. La presentación clínico-imagenológica plantea como principales diagnósticos diferenciales a carcinomas o lesiones benignas tales como los fibroadenomas, por lo cual la biopsia escisional es el tratamiento de elección. La comunicación del presente caso pretende destacar la importancia del diagnóstico diferencial de esta entidad patológica mamaria de baja incidencia cuya etiología es sistémica. Se trata de una paciente de 45 años de edad, oriunda de Córdoba capital, taxista,  con antecedentes tóxicos de tabaquismo y etilismo; antecedentes personales patológicos diabetes tipo I tratada con insulina NPH y buenos controles glucémicos. Consulta por guardia central por presentar en mama derecha, tumoración eritematosa flogótica de 40 días de evolución. Había realizado tratamiento antibiótico con amoxicilina-ácido clavulánico durante dos semanas, sin obtener respuesta. Se realiza mamografía encontrándose en mama derecha, área radiopaca de bordes difusos lobulados que provoca retracción del pezón y franco engrosamiento cutáneo, de aspecto proliferativo (clasificación BIRADS V). Se realiza biopsia incisional, drenaje, indicandose internación y tratamiento antibiótico combinado (clindamicina+gentamicina). Evoluciona favorablemente y posteriormente se recibe informe de anatomía patológica. En la macroscopia se observan cuatro fragmentos de tejido de forma irregular de aproximadamente 2x1 cm, los cuales presentan al corte colorido blanquecino y consistencia firme. La histopatología informa cortes procesados con técnicas habituales y coloreados con H&E,  que exhiben en el tejido mamario estroma denso, haces hialinos prominentes de colágeno, vasos sanguíneos de paredes hialinas engrosadas, las cuales producen estenosis de la luz. Se observa importante infiltrado inflamatorio mononuclear, leucocitos polimorfonucleares neutrófilos e histiocitos, conductos con células epiteliales reactivas al proceso inflamatorio y áreas de necrosis. Piel con leucocitos polimorfonucleares en migración transepitelial. Los hallazgos descriptos son vinculables a Mastopatía diabética/mastitis aguda inespecífica. El caso clínico expuesto, destaca que ante una lesión clínico-imagenológica sugestiva de malignidad, resulta fundamental considerar siempre el contexto clínico ya que a pesar de su baja prevalencia, la MD es una entidad a considerar, sobre todo en pacientes con antecedentes de diabetes tipo I.

Hydrostatic equilibrium configurations of neutron stars in the f(R,L,T)f(R,\mathcal{L},T) gravity theory

In the present work, we obtain the hydrostatic equilibrium configurations of neutron stars in the recently proposed $f(R,\mathcal{L},T)$ theory of gravity, for which $R$ is the Ricci scalar, $\mathcal{L}$ is the matter lagrangian density, $T$ is the trace of the energy-momentum tensor and $f$ is a function of the argument. This theory emerges in the present literature as a generalized geometry-matter coupling theory of gravity. We derive the Tolman-Oppenheimer-Volkoff-like equation for a particular functional form of the $f(R,\mathcal{L},T)$ function. Our solutions are obtained from realistic equations of state describing matter inside neutron stars. We obtain stable solutions for neutron stars and we show that for some values of the free parameter of the theory it is possible to be in agreement with both NICER and LIGO/Virgo observational data

Relationship between herpes simplex virus-1-specific antibody titers and cortical brain damage in Alzheimer's disease and amnestic mild cognitive impairment

This work was supported by 2012–2014 Ricerca Corrente (Italian Ministry of Health).Alzheimer's disease (AD) is a multifactorial disease with a still barely understood etiology. Herpes simplex virus 1 (HSV-1) has long been suspected to play a role in the pathogenesis of AD because of its neurotropism, high rate of infection in the general population, and life-long persistence in neuronal cells, particularly in the same brain regions that are usually altered in AD. The goal of this study was to evaluate HSV-1-specific humoral immune responses in patients with a diagnosis of either AD or amnestic mild cognitive impairment (aMCI), and to verify the possible relation between HSV-1-specific antibody (Ab) titers and cortical damage; results were compared to those obtained in a group of healthy controls (HC). HSV-1 serum IgG titers were measured in 225 subjects (83 AD, 68 aMCI, and 74 HC). HSV-specific Ab avidity and cortical gray matter volumes analyzed by magnetic resonance imaging (MRI) were evaluated as well in a subgroup of these individuals (44 AD, 23 aMCI, and 26 HC). Results showed that, whereas HSV-1 seroprevalence and IgG avidity were comparable in the three groups, increased Ab titers (p < 0.001) were detected in AD and aMCI compared to HC. Positive significant correlations were detected in AD patients alone between HSV-1 IgG titers and cortical volumes in orbitofrontal (region of interest, ROI1 RSp0.56; p = 0.0001) and bilateral temporal cortices (ROI2 RSp0.57; p < 0.0001; ROI3 RSp0.48; p = 0.001); no correlations could be detected between IgG avidity and MRI parameters. Results herein suggest that a strong HSV-1-specific humoral response could be protective toward AD-associated cortical damage.Publisher PDFPeer reviewe

Immune regulation of neurodevelopment at the mother–foetus interface: the case of autism

Autism spectrum disorder (ASD) is a neurodevelopmental disorder defined by deficits in social communication and stereotypical behaviours. ASD’s aetiology remains mostly unclear, because of a complex interaction between genetic and environmental factors. Recently, a strong consensus has developed around ASD’s immune-mediated pathophysiology, which is the subject of this review. For many years, neuroimmunological studies tried to understand ASD as a prototypical antibody- or cell-mediated disease. Other findings indicated the importance of autoimmune mechanisms such as familial and individual autoimmunity, adaptive immune abnormalities and the influence of infections during gestation. However, recent studies have challenged the idea that autism may be a classical autoimmune disease. Modern neurodevelopmental immunology shows the double-edged nature of many immune effectors, which can be either beneficial or detrimental depending on tissue homeostasis, stressors, neurodevelopmental stage, inherited and de novo gene mutations and other variables. Nowadays, mother–child interactions in the prenatal environment appear to be crucial for the occurrence of ASD. Studies of animal maternal–foetal immune interaction are being fruitfully carried out using different combinations of type and timing of infection, of maternal immune response and foetal vulnerability and of resilience factors to hostile events. The derailed neuroimmune crosstalk through the placenta initiates and maintains a chronic foetal neuroglial activation, eventually causing the alteration of neurogenesis, migration, synapse formation and pruning. The importance of pregnancy can also allow early immune interventions, which can significantly reduce the increasing risk of ASD and its heavy social burden