Correlation between real geometry and tensile mechanical behaviour for Ti6Al4V electron beam melted thin specimens

The Electron Beam Melting (EBM) is an Additive Layer Manufacturing (ALM) technique used to directly manufacture 3D functional parts from metal powder, selectively melted, layer by layer, by an electron beam according to a geometry defined by a CAD model. The EBM technology allows benefitting from countless advantages: material waste reduction, easy manufacturing of complex shapes, lead time reduction, etc; on the other hand the EBM process is typically associated with lower resolutions and higher surface roughness (Ra = 25–30 μm) compared to similar laser based powder bed metal processes. Therefore the surface morphology may be a critical issue for the structural integrity of components made in EBM and used in-service in their “as built” condition, i.e. with the characteristic surface released by the process. This study evaluates surface morphology and tensile properties of Ti6Al4V specimens of varying nominal thickness (1–5.0 mm), made by using EBM process with a layer thickness of 50 μm. The aim is therefore to investigate how the surface morphology and the tensile properties are affected by the nominal thickness of the component

Bioaerosol emissions during organic waste treatment for biopolymer production: A case study

Environmentally sustainable methods of waste disposal are a strategic priority. For organic waste management and innovative biological treatments present advantageous opportunities, although organic waste treatment also includes environmental drawbacks, such as bioaerosol pro-duction. This study aims to evaluate bioaerosol spread during an innovative experimental treatment. The process consists of two anaerobic steps: acidogenesis, which includes polyhydroxyalkanoate accumulation, followed by methanogenesis. Bioaerosol, PM10, and endotoxin concentrations were measured at three sampling points during different campaigns to evaluate: (1) the background levels, (2) the contamination produced in the pre-treatment stage, and (3) the residual contamination of the outgoing digested sludge. Environmental PM10 seemed to be generally quite contained, while the endotoxin determination was close to 90 EU/m3. Significant microbial concentrations were detected during the loading of the organic fraction of municipal solid waste (fungi > 1300 CFU/m3, Bacillus genus (≈103 CFU/m3), higher Clostridium spp. and opportunistic human pathogens such as Pseudomonas aeruginosa and Klebsiella pneumoniae), suggesting a significant contamination level. Such results are useful for hazard identification in the risk assessment of innovative processes, as they reveal contaminants potentially harmful to both workers’ health and the environment

Precision medicine and public health: New challenges for effective and sustainable health

The development of high-throughput omics technologies represents an unmissable opportunity for evidence-based prevention of adverse effects on human health. However, the applicability and access to multi-omics tests are limited. In Italy, this is due to the rapid increase of knowledge and the high levels of skill and economic investment initially necessary. The fields of human genetics and public health have highlighted the relevance of an implementation strategy at a national level in Italy, including integration in sanitary regulations and governance instruments. In this review, the emerging field of public health genomics is discussed, including the polygenic scores approach, epigenetic modulation, nutrigenomics, and microbiomes implications. Moreover, the Italian state of implementation is presented. The omics sciences have important implications for the prevention of both communicable and noncommunicable diseases, especially because they can be used to assess the health status during the whole course of life. An effective population health gain is possible if omics tools are implemented for each person after a preliminary assessment of effectiveness in the medium to long term

Genomica in Sanità Pubblica. Evidenze scientifiche e prospettive di integrazione nella pratica della prevenzione

I miglioramenti registrati negli ultimi anni nella qualità del sequenziamento di nuova generazione, nella riduzione dei costi associati e in una complessiva evoluzione delle scienze omiche, hanno favorito lo sviluppo della medicina personalizzata o di precisione. Ad oggi, anche a livello di popolazione si possono ottenere dei benefici rilevanti attraverso tale approccio. La Sanità Pubblica di precisione consiste nel fornire il giusto intervento, alla popolazione che ne ha necessità, nel momento e con le modalità opportune. Significa, quindi, promuovere metodologie accurate per identificare e misurare le patologie ma anche le esposizioni, i comportamenti e la suscettibilità. La Sanità Pubblica di precisione è in evoluzione e non è legata semplicemente a geni, trattamenti e malattia ma alla precisa identificazione e risposta ai bisogni di salute. È necessario, quindi, discutere dell’inclusione delle scienze omiche in Sanità Pubblica. La medicina si è evoluta da un modello di diagnosi e trattamento basato essenzialmente sui sintomi ad uno sempre più dipendente dalla definizione bioinformatica di profili di rischio e/o patologici. Tali profili sono delineati mediante la produzione di informazioni attingendo a solide banche dati biologiche con il supporto dell’intelligenza artificiale. D’altra parte l’evoluzione nella pratica sanitaria è un processo complesso che include, tra l’altro, la sostenibilità dei costi sanitari, la valutazione dell’efficienza nella pratica clinica, l'integrazione dei nuovi progressi tecnologici e la rimodulazione dell'organizzazione dei servizi. Nel Gruppo di Lavoro Genomica in Sanità Pubblica della SItI, attivo dal 2012, sono coinvolti prevalentemente docenti universitari ma anche operatori del Ministero della Salute e dei Dipartimenti di Prevenzione. In questo special issue illustriamo alcuni argomenti di ricerca trattati. Non stupirà l’eterogeneità dei temi proposti vista la trasversalità delle scienze omiche in molteplici aspetti della salute umana. In particolare sono illustrati esempi che vanno dalla prevenzione di tumori ad alta incidenza, alla prevenzione di patologie infettive, sia per gli aspetti acuti che cronici, tenendo conto di caratteristiche genetiche ed epigenetiche della popolazione. Inoltre, illustriamo le prospettive di integrazione offerte allo studio del microbiota umano nella prevenzione. Procediamo con la discussione delle modalità di valutazione dei test genetici e genomici per la loro integrazione nell’offerta del Servizio Sanitario Nazionale. Infine, è illustrato il coinvolgimento della popolazione nell’impiego delle tecnologie omiche al fine di promuovere un cambiamento culturale nei confronti delle tecnologie disponibili e nella tutela della salute individuale e collettiva

Implications of early respiratory support strategies on disease progression in critical COVID-19: a matched subanalysis of the prospective RISC-19-ICU cohort.

Uncertainty about the optimal respiratory support strategies in critically ill COVID-19 patients is widespread. While the risks and benefits of noninvasive techniques versus early invasive mechanical ventilation (IMV) are intensely debated, actual evidence is lacking. We sought to assess the risks and benefits of different respiratory support strategies, employed in intensive care units during the first months of the COVID-19 pandemic on intubation and intensive care unit (ICU) mortality rates. Subanalysis of a prospective, multinational registry of critically ill COVID-19 patients. Patients were subclassified into standard oxygen therapy ≥10 L/min (SOT), high-flow oxygen therapy (HFNC), noninvasive positive-pressure ventilation (NIV), and early IMV, according to the respiratory support strategy employed at the day of admission to ICU. Propensity score matching was performed to ensure comparability between groups. Initially, 1421 patients were assessed for possible study inclusion. Of these, 351 patients (85 SOT, 87 HFNC, 87 NIV, and 92 IMV) remained eligible for full analysis after propensity score matching. 55% of patients initially receiving noninvasive respiratory support required IMV. The intubation rate was lower in patients initially ventilated with HFNC and NIV compared to those who received SOT (SOT: 64%, HFNC: 52%, NIV: 49%, p = 0.025). Compared to the other respiratory support strategies, NIV was associated with a higher overall ICU mortality (SOT: 18%, HFNC: 20%, NIV: 37%, IMV: 25%, p = 0.016). In this cohort of critically ill patients with COVID-19, a trial of HFNC appeared to be the most balanced initial respiratory support strategy, given the reduced intubation rate and comparable ICU mortality rate. Nonetheless, considering the uncertainty and stress associated with the COVID-19 pandemic, SOT and early IMV represented safe initial respiratory support strategies. The presented findings, in agreement with classic ARDS literature, suggest that NIV should be avoided whenever possible due to the elevated ICU mortality risk

Robust and persistent reactivation of SIV and HIV by N-803 and depletion of CD8+ cells

Human immunodeficiency virus (HIV) persists indefinitely in individuals with HIV who receive antiretroviral therapy (ART) owing to a reservoir of latently infected cells that contain replication-competent virus1–4. Here, to better understand the mechanisms responsible for latency persistence and reversal, we used the interleukin-15 superagonist N-803 in conjunction with the depletion of CD8+ lymphocytes in ART-treated macaques infected with simian immunodeficiency virus (SIV). Although N-803 alone did not reactivate virus production, its administration after the depletion of CD8+ lymphocytes in conjunction with ART treatment induced robust and persistent reactivation of the virus in vivo. We found viraemia of more than 60 copies per ml in all macaques (n = 14; 100%) and in 41 out of a total of 56 samples (73.2%) that were collected each week after N-803 administration. Notably, concordant results were obtained in ART-treated HIV-infected humanized mice. In addition, we observed that co-culture with CD8+ T cells blocked the in vitro latency-reversing effect of N-803 on primary human CD4+ T cells that were latently infected with HIV. These results advance our understanding of the mechanisms responsible for latency reversal and lentivirus reactivation during ART-suppressed infection

Correlation between real geometry and tensile mechanical behaviour for Ti6Al4V electron beam melted thin specimens

The Electron Beam Melting (EBM) is an Additive Layer Manufacturing (ALM) technique used to directly manufacture 3D functional parts from metal powder, selectively melted, layer by layer, by an electron beam according to a geometry defined by a CAD model. The EBM technology allows benefitting from countless advantages: material waste reduction, easy manufacturing of complex shapes, lead time reduction, etc; on the other hand the EBM process is typically associated with lower resolutions and higher surface roughness (Ra = 25–30 μm) compared to similar laser based powder bed metal processes. Therefore the surface morphology may be a critical issue for the structural integrity of components made in EBM and used in-service in their “as built” condition, i.e. with the characteristic surface released by the process. This study evaluates surface morphology and tensile properties of Ti6Al4V specimens of varying nominal thickness (1–5.0 mm), made by using EBM process with a layer thickness of 50 μm. The aim is therefore to investigate how the surface morphology and the tensile properties are affected by the nominal thickness of the component

Chemical surface finishing of electron beam melted Ti6Al4V using HF-HNO3 solutions

Electron Beam Melting is an Additive Manufacturing technology that allows the production of items using metal powder as raw material. The main advantage of Additive Manufacturing (AM) is realizing complex shape components; however one of the main defects is the poor quality of the surface. To this aim, different post processing treatments have been proposed such as machining, surface laser melting, sand blasting, etc. The main drawback of these technologies is the necessity to use tools that makes complex shape item difficult to handle. This inconvenient does not occur in chemical machining, since a chemical solution can operate in an undifferentiated way on the whole surface of a component. In this work some components in Ti6Al4V obtained through AM have been treated in acidic solutions containing HF and HNO3 with different HF/HNO3 molar ratio. All the solutions employed have proven to be effective in smoothing the metal surface, but the best results have been obtained with solutions with high content of HNO3. It should be noted that the process causes changes in the surface composition with respect to the received samples with an impoverishment of Al. This effect is partially mitigated by the passivating action of HNO3