Optimization of the wavesax device: numerical modelling and ocean wave basin tests

The Wavesax device has been conceived to be installed in ports and harbours, in the Mediterranean sea. Therefore, two aspects are quite important: flexibility of the device to fit in different structural configurations and replication in a large number of units. Preliminary numerical modelling of the fixed component of the device has been performed using Computational Fluid Dynamics analysis (RANS-CFD model) and considering four regular wave conditions typical of the Mediterranean sea. Main issues to be considered in the first stage scale modelling analysis are the effective functionality of the device conception (scale 1:20), the optimization of the design and position of the device in terms of generated velocity gradients in the working section where the turbine blades are installed. The main parameters to be investigated, both with numerical modelling and ocean wave basin tests, are the pressure field in different sections of the device, water levels for different wave conditions and device sinking. Following the scale model test, the numerical model was calibrated and validated. The paper presents the results of the numerical simulations related to different configurations of the device, under typical Mediterranean wave climates

Characterization of soot produced by the mini inverted soot generator with an atmospheric simulation chamber

The performance of a mini inverted soot generator (MISG) has been investigated at ChAMBRe (Chamber for Aerosol Modelling and Bio-aerosol Research) by studying the properties of soot particles generated by ethylene and propane combustion. This work deepens and expands the existing characterization of the MISG, which also exploits an atmospheric simulation chamber (ASC). Different from previous works, MISG performance has been also tested at different fuel flows and higher global equivalence ratios. MISG exhausts were investigated after their injection inside the atmospheric simulation chamber, which is another novelty of this work. Starting from an extensive classification of combustion conditions and resulting flame shapes, the MISG exhaust was characterized in terms of concentration of emitted particles and gases, particle size distribution, and optical properties. Soot particles were also collected on quartz fibre filters and then analysed by optical and thermal\u2013optical techniques to measure the spectral dependence of the absorption coefficient babs and their composition in terms of elemental carbon and organic carbon (EC and OC). Significant differences could be observed when the MISG was fuelled with ethylene and propane in terms of particle size. In particular, the production of super-micrometric aggregates was observed for ethylene combustion. With equal combustion conditions, ethylene produced a higher number concentration of particles and smaller mode diameters. Soot particles produced by propane combustion resulted in higher EC : TC (total carbon) ratios and they were more light absorbing than particles generated by ethylene combustion. Values of the mass absorption cross section (MAC) and of the \uc5ngstr\uf6m absorption exponent (AAE) turned out to be compatible with the literature, even if there were some specific differences. The comprehensive characterization of the MISG soot particles is an important piece of information to design and perform experiments in atmospheric simulation chambers. Particles with well-known properties can be used, for example, to investigate the possible interactions between soot and other atmospheric pollutants, the effects of meteorological variables on soot properties, and the oxidative and toxicological potential of soot particles

Continuous monitoring of cerebral oxygen saturation in elderly patients undergoing major abdominal surgery minimizes brain exposure to potential hypoxia

to develop cerebral desaturation because of the reduced physiologic reserve that accompanies aging. To evaluate whether monitoring cerebral oxygen saturation (rSO2) minimizes intraoperative cerebral desaturation, we prospectively monitored rSO2 in 122 elderly patients undergoing major abdominal surgery with general anesthesia. Patients were randomly allocated to an intervention group (the monitor was visible and rSO2 was maintained at 75% of preinduction values; n 56) or a control group (the monitor was blinded and anesthesia was managed routinely; n 66). Cerebral desaturation (rSO2 reduction 75% of baseline) was observed in 11 patients of the treatment group (20%) and 15 patients of the control group (23%) (P 0.82). Mean (95% confidence intervals) values of mean rSO2 were higher (66% [64%–68%]) and the area under the curve below 75% of baseline (AUCrSO2275% of baseline) was lower (0.4 min% [0.1– 0.8 min%]) in patients of the treatment group than in patients of the control group (61% [59%–63%] and 80 min% [2–144 min%], respectively; P 0.002 and P 0.017). When considering only patients developing intraoperative cerebral desaturation, a lower Mini Mental State Elimination (MMSE) score was observed at the seventh postoperative day in the control group (26 [25–30]) than in the treatment group (28 [26 –30]) (P 0.02), with a significant correlation between the AUCrSO2 75% of baseline and postoperative decrease in MMSE score from preoperative values (r20.25, P0.01). Patients of the control group with intraoperative cerebral desaturation also experienced a longer time to postanesthesia care unit (PACU) discharge (47 min [13–56 min]) and longer hospital stay (24 days [7–53] days) compared with patients of the treatment group (25 min [15–35 min] and 10 days [7–23 days], respectively; P 0.01 and P 0.007). Using rSO2 monitoring to manage anesthesia in elderly patients undergoing major abdominal surgery reduces the potential exposure of the brain to hypoxia; this might be associated with decreased effects on cognitive function and shorter PACU and hospital stay

Role of protein kinase R in the killing of Leishmania major by macrophages in response to neutrophil elastase and TLR4 via TNF and IFN

In cutaneous leishmaniasis, Leishmania amazonensis activates macrophage double-stranded, RNA-activated protein kinase R (PKR) to promote parasite growth. In our study, Leishmania major grew normally in RAW cells, RAW-expressing dominant-negative PKR (PKR-DN) cells, and macrophages of PKR-knockout mice, revealing that PKR is dispensable for L. major growth in macrophages. PKR activation in infected macrophages with poly I:C resulted in parasite death. Fifty percent of L. major-knockout lines for the ecotin-like serine peptidase inhibitor (ISP2; Δisp2/isp3), an inhibitor of neutrophil elastase (NE), died in RAW cells or macrophages from 129Sv mice, as a result of PKR activation. Inhibition of PKR or NE or neutralization of Toll-like receptor 4 or 2(TLR4 or TLR2) prevented the death of Δisp2/isp3. Δisp2/isp3 grew normally in RAW-PKR-DN cells or macrophages from 129Sv pkr−/−, tlr2−/−, trif−/−, and myd88−/− mice, associating NE activity, PKR, and TLR responses with parasite death. Δisp2/isp3 increased the expression of mRNA for TNF-α by 2-fold and of interferon β (IFNβ) in a PKR-dependent manner. Antibodies to TNF-α reversed the 95% killing by Δisp2/isp3, whereas they grew normally in macrophages from IFN receptor–knockout mice. We propose that ISP2 prevents the activation of PKR via an NE-TLR4-TLR2 axis to control innate responses that contribute to the killing of L. major.—Faria, M. S., Calegari-Silva, T. C., de Carvalho Vivarini, A., Mottram, J. C., Lopes, U. G., Lima, A. P. C. A. Role of protein kinase R in the killing of Leishmania major by macrophages in response to neutrophil elastase and TLR4 via TNFα and IFNβ

Differences in visceral fat and fat bacterial colonization between ulcerative colitis and Crohn's disease. An in vivo and in vitro study

Crohn's disease (CD) is notably characterized by the expansion of visceral fat with small adipocytes expressing a high proportion of anti-inflammatory genes. Conversely, visceral fat depots in ulcerative colitis (UC) patients have never been characterized. Our study aims were a) to compare adipocyte morphology and gene expression profile and bacterial translocation in omental (OM) and mesenteric (MES) adipose tissue of patients with UC and CD, and b) to investigate the effect of bacterial infection on adipocyte proliferation in vitro. Specimens of OM and MES were collected from 11 UC and 11 CD patients, processed and examined by light microscopy. Gene expression profiles were evaluated in adipocytes isolated from visceral adipose tissue using microarray and RTqPCR validations. Bacteria within adipose tissue were immuno-detected by confocal scanning laser microscopy. Adipocytes were incubated with Enterococcus faecalis and cells counted after 24 h. Morphology and molecular profile of OM and MES revealed that UC adipose tissue is less inflamed than CD adipose tissue. Genes linked to inflammation, bacterial response, chemotaxis and angiogenesis were down-regulated in adipocytes from UC compared to CD, whereas genes related to metallothioneins, apoptosis pathways and growth factor binding were up-regulated. A dense perinuclear positivity for Enterococcus faecalis was detected in visceral adipocytes from CD, whereas positivity was weak in UC. In vitro bacterial infection was associated with a five-fold increase in the proliferation rate of OM preadipocytes. Compared to UC, visceral adipose tissue from CD is more inflamed and more colonized by intestinal bacteria, which increase adipocyte proliferation. The influence of bacteria stored within adipocytes on the clinical course of IBD warrants further investigation

How many deficits in the same dyslexic brains? A behavioural and fMRI assessment of comorbidity in adult dyslexics

Dyslexia can have different manifestations: this has motivated different theories on its nature, on its underlying brain bases and enduring controversies on how to best treat it. The relative weight of the different manifestations has never been evaluated using both behavioural and fMRI measures, a challenge taken here to assess the major systems called into play in dyslexia by different theories. We found that adult well-compensated dyslexics were systematically impaired only in reading and in visuo-phonological tasks, while deficits for other systems (e.g., motor/cerebellar, visual magnocellular/motion perception) were only very occasional. In line with these findings, fMRI showed a reliable hypoactivation only for the task of reading, in the left occipito-temporal cortex (l-OTC). The l-OTC, normally a crossroad between the reading system and other systems, did not show the same level of intersection in dyslexics; yet, it was not totally silent because it responded, in segregated parts, during auditory phonological and visual motion perception tasks. This minimal behavioural and functional anatomical comorbidity demonstrates that a specific deficit of reading is the best description for developmental dyslexia, at least for adult well-compensated cases, with clear implications for rehabilitation strategies. The reduced intersection of multiple systems in the l-OTC suggests that dyslexics suffer from a coarser connectivity, leading to disconnection between the multiple domains that normally interact during reading

Impact of COVID-19 on the oncological outcomes of colorectal cancer surgery in northern Italy in 2019 and 2020: multicentre comparative cohort study

BACKGROUND: This study compared patients undergoing colorectal cancer surgery in 20 hospitals of northern Italy in 2019 versus 2020, in order to evaluate whether COVID-19-related delays of colorectal cancer screening resulted in more advanced cancers at diagnosis and worse clinical outcomes. METHOD: This was a retrospective multicentre cohort analysis of patients undergoing colorectal cancer surgery in March to December 2019 versus March to December 2020. Independent predictors of disease stage (oncological stage, associated symptoms, clinical T4 stage, metastasis) and outcome (surgical complications, palliative surgery, 30-day death) were evaluated using logistic regression. RESULTS: The sample consisted of 1755 patients operated in 2019, and 1481 in 2020 (both mean age 69.6 years). The proportion of cancers with symptoms, clinical T4 stage, liver and lung metastases in 2019 and 2020 were respectively: 80.8 versus 84.5 per cent; 6.2 versus 8.7 per cent; 10.2 versus 10.3 per cent; and 3.0 versus 4.4 per cent. The proportions of surgical complications, palliative surgery and death in 2019 and 2020 were, respectively: 34.4 versus 31.9 per cent; 5.0 versus 7.5 per cent; and 1.7 versus 2.4 per cent. Cancers in 2020 (versus 2019) were more likely to be symptomatic (odds ratio 1.36 (95 per cent c.i. 1.09 to 1.69)), clinical T4 stage (odds ratio 1.38 (95 per cent c.i. 1.03 to 1.85)) and have multiple liver metastases (odds ratio 2.21 (95 per cent c.i. 1.24 to 3.94)), but were not more likely to be associated with surgical complications (odds ratio 0.79 (95 per cent c.i. 0.68 to 0.93)). CONCLUSION: Colorectal cancer patients who had surgery between March and December 2020 had an increased risk of advanced disease in terms of associated symptoms, cancer location, clinical T4 stage and number of liver metastases

Solid state and solution fine tuning of the linear and nonlinear optical properties of (2-pyrene-1-yl-vinyl)pyridine by protonation–deprotonation reactions

The unexpected and acido-triggered reversible luminescence and nonlinear optical properties of (2-pyrene-1-yl-vinyl)pyridine, a simple and highly transparent chromophore, are studied both in solution and in the solid state. Remarkably, for the first time the acidomodulation of the NLO response of a poled thin film is reported

ChAMBRe: studi su bio-aerosol in camera di simulazione atmosferica

Nella Sezione di Genova dell\u2019Istituto Nazionale di Fisica Nucleare \ue8 stata recentemente installata, in collaborazione con il Laboratorio di Fisica Ambientale del Dipartimento di Fisica dell\u2019Universit\ue0 di Genova, ChAMBRe (Chamber for Aerosol Modelling and Bio-aerosol Research), la prima Camera di simulazione atmosferica specificatamente concepita per studiare la componente biologica dell\u2019aerosol atmosferico. Presso la camera di simulazione atmosferica CESAM (Cr\ue9teil, Francia) sono sati effettuati alcuni esperimenti pilota recentemente pubblicati [1], che sono stati lo spunto per la costruzione di una struttura dedicata allo studio del comportamento dei pi\uf9 comuni agenti patogeni presenti in atmosfera sotto forma di bioaerosol e in particolare dei meccanismi che controllano le interazioni tra questi e le altre componenti dell\u2019aerosol e pi\uf9 in generale dell\u2019atmosfera. L\u2019attivit\ue0 di ricerca a ChAMBRe si concentrer\ue0 sull\u2019indagine del comportamento del bio-aerosol in differenti condizioni atmosferiche e in presenza di tipici inquinanti antropici (come il monossido di carbonio, gli ossidi di azoto, etc.) che possono influenzare la vitalit\ue0, la morfologia e la dispersione dei batteri in atmosfera. Come primo passo \ue8 necessario innanzitutto mettere a punto un protocollo che garantisca la riproducibilit\ue0 degli esperimenti in una struttura complessa come ChAMBRe. Ci si \ue8 quindi concentrati su aspetti cruciali quali: crescita in vitro e successiva iniezione in camera di una data concentrazione di batteri, seguita da una fase di estrazione, campionamento e misura della vita media all\u2019interno della camera. Gli esperimenti sono volti anche ad identificare eventuali condizioni di stress ambientali e meccaniche per i microrganismi e la loro risposta come singoli individui e come colonie. Sono stati eseguiti esperimenti su due tipologie di ceppi batterici frequentemente utilizzati come organismi modello: il Bacillus subtilis e l\u2019Escherichia coli, appartenenti rispettivamente al gruppo dei Gram-positivi e dei Gram-negativi. I risultati e il protocollo sperimentale messo a punto verranno presentati a PM2018