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Background: Prone positioning (PP) is routinely used among patients with COVID-19 requiring mechanical ventilation (MV). However, its utility among spontaneously breathing patients is still debated. Methods: In an open-label randomised controlled trial, we enrolled patients hospitalised with mild COVID-19 pneumonia, whose PaO2/FiO2 ratio (P/F) was >200 mmHg and who did not require MV or Continuous Positive Airway Pressure (CPAP) at hospital admission. Patients were randomised 1:1 to PP on top of standard of care (intervention group) versus standard of care only (controls). The primary composite outcome included death, MV, CPAP and P/F <200 mmHg; secondary outcomes were oxygen weaning and hospital discharge. Results: Sixty-one subjects were enrolled, 29 adjudicated to PP and 32 to the control group. By day 28, 24/61 (39.3%) patients met the primary outcome: 16 because of P/F ratio <200 mmHg, 5 CPAP and 3 MV. Three patients died. Using an intention-to-treat approach, 15/29 patients in PP group versus 9/32 controls met the primary outcome, corresponding to a significantly higher risk of progression among those randomised to PP (HR 2.38 [95%CI 1.04-5.43]; p=0.040). Using an as-treated approach, which included in the intervention group only patients who maintained PP for ≥3 h·day-1, no significant differences were found between the two groups (HR 1.77; [95%CI 0.79-3.94]; p=0.165). Also, we did not find any statistically significant difference in terms of time to oxygen weaning or hospital discharge between study arms, in any of the analyses conducted. Conclusions: We observed no clinical benefit from PP among spontaneously breathing patients with COVID-19 pneumonia requiring conventional oxygen therapy.

Healthy aging is an ambitious aspiration for humans, but neurodegenerative disorders, such as Alzheimer's disease (AD), strongly affect quality of life. Using an integrated omics approach, we investigate alterations in the molecular composition of postmortem hippocampus samples of healthy persons and individuals with AD. Profound differences are apparent between control and AD male and female cohorts in terms of up- and downregulated metabolic pathways. A decrease in the insulin response is evident in AD when comparing the female with the male group. The serine metabolism (linked to the glycolytic pathway and generating the N-methyl-D-aspartate [NMDA] receptor coagonist D-serine) is also significantly modulated: the D-Ser/total serine ratio represents a way to counteract age-related cognitive decline in healthy men and during AD onset in women. These results show how AD changes and, in certain respects, almost reverses sex-specific proteomic and metabolomic profiles, highlighting how different pathophysiological mechanisms are active in men and women.

La diffusione del lavoro da remoto a seguito della pandemia da Coronavirus ha fatto emergere numerose criticità che hanno spinto le organizzazioni sindacali ad interrogarsi sull’inclusione di questa modalità organizzativa nel campo della contrattazione collettiva. L'articolo si propone di analizzare le pratiche quotidiane di contrattazione sindacale, indagando come le principali linee guida sul lavoro da remoto sono state concretamente implementate durante la pandemia. Sulla base di dati empirici raccolti in Veneto, e partendo dalla prospettiva di funzionari e rappresentanti sindacali, l'articolo fa luce sulle pratiche di contrattazione sindacale riguardanti: la possibilità di accedere al lavoro a distanza, il reddito, l'orario e i carichi di lavoro. I risultati mostrano come funzionari e delegati sindacali adattino le strategie delle loro organizzazioni agli specifici settori e luoghi di lavoro in cui sono inseriti, in base alle esigenze specifiche della forza lavoro che rappresentano e a come percepiscono il loro potere contrattuale. In conclusione, sosteniamo che le diverse variabili - livello geografico, settore, precedente esperienza di contrattazione, posizione ideologica dei sindacalisti, percezione del proprio potere contrattuale - si intersecano tra loro, producendo una geometria variabile di pratiche di contrattazione sul lavoro da remoto., The spreading of remote work in Italy following the Coronavirus pandemic has brought numerous challenges that have prompted trade unions to include this form of work as a matter of collective bargaining. The article aims to study unions’ everyday bargaining practices, by investigating how the main union guidelines on remote work have been implemented during the pandemic. Based on empirical data collected in Veneto, and starting from the perspective of union officials and representatives, the article sheds light on unions’ bargaining practices concerning access to remote work, remote workers’ income, working time, and workloads. The analysis permits us to stress that union practitioners adapt the strategies of their union organisations to the specific sectors and workplaces in which they are embedded, according to the specific needs of the workforce they represent and to how they perceive their own bargaining power. We argue that the different variables - geographical level, sector, previous bargaining experience, unionists' ideological position, perception of their own bargaining power - intersect with each other, producing a variable geometry of bargaining practices with regard to remote work.

Background: The infectious disease phenotype of acute stroke associated with COVID-19 has been poorly characterized. Objective: We investigated the neurovascular and infectious disease phenotype of stroke patients with and without COVID-19 infection, and their effect on in-hospital mortality. Methods: This is a retrospective cohort study of consecutive patients with acute stroke, admitted to any ward of a hub hospital for stroke in Lombardy, Italy, during the first wave of COVID-19. Demographic, neurovascular, infectious disease, and respiratory characteristics were collected. The effect of clinical variables on survival was evaluated using logistic regression models. Results: One hundred thirty-seven patients with acute stroke were recruited; 30 (21.9%) patients had COVID-19 and represented 2.5% of the 1218 COVID-19 patients hospitalized in the study period. Demographics, comorbidities, stroke type, stroke severity, and etiology did not differ between COVID + stroke patients and non-COVID stroke patients, except for an excess of multi-embolic ischemic stroke in the COVID + group. Most COVID + stroke patients had symptomatic infection (60%) and interstitial pneumonia (70%). COVID + stroke patients required more frequently respiratory support (77% versus 29%; p < 0.0001) and had higher in-hospital mortality (40% versus 12%; p = 0.0005) than non-COVID stroke patients. Mortality was independently associated with symptomatic interstitial pneumonia (aOR 6.7; 95% CI 2.0–22.5; p = 0.002) and, to a lesser extent, with NIHSS on admission (aOR 1.1; 95% CI 1.03–1.2; p = 0.007) and recanalization therapies (aOR 0.2; 95% CI 0.04–0.98; p = 0.046). Conclusion: Symptomatic interstitial pneumonia was the major driver of in-hospital mortality in COVID + stroke patients.

Vi è un’estesa sovrapposizione geografica tra malaria e infezione da HIV nell’Africa Sub-Sahariana e, in minor misura, nel Sud-Est Asiatico. In Europa e Nord America i casi di malaria nei pazienti HIV positivi sono limitati ai viaggiatori in aree malariche senza idonea profilassi. La co-infezione malaria-HIV (CMH) comporta un aumento della viremia e una riduzione del numero dei linfociti CD4+, l’incremento della parassitemia e della frequenza di gametocitemia persistente, più frequenti complicanze da malaria grave e mortalità più elevata. La CMH in gravidanza aumenta il rischio di complicanze perinatali (parto pre-termine, aumentata mortalità neonatale, anemia grave). Nella scelta del trattamento antimalarico è necessario tenere in considerazione le numerose interazioni farmacologiche con la terapia antiretrovirale. In generale gli inibitori delle proteasi e gli NNRTI sono i farmaci con il maggior numero di interazioni farmacologiche con le terapie di combinazione a base di derivati dell’artemisinina. L’allungamento del tratto QT è l’evento avverso più frequente e che richiede un monitoraggio ECG più attento nei pazienti in trattamento antiretrovirale. Il paziente con infezione da HIV necessita pertanto un attento monitoraggio degli effetti collaterali in corso di terapia e rivalutazione nelle settimane successive per assicurarsi l’efficacia del trattamento antimalarico., There is extensive geographical overlap between malaria and HIV infection in Sub-Saharan Africa and, to a lesser extent, Southeast Asia. In Europe and North America, malaria cases in HIV-positive patients are limited to travellers in malarial areas without appropriate prophylaxis. Malaria-HIV co-infection (MHC) results in increased viremia and reduced CD4+ counts, increased parasitaemia and frequency of persistent gametocytaemia, more frequent severe malaria complications and higher mortality. MHC in pregnancy increases the risk of perinatal complications (pre-term delivery, increased neonatal mortality, severe anaemia). Numerous drug interactions with antiretroviral therapy must be considered when choosing antimalarial treatment. In general, protease inhibitors and NNRTIs are the antiretrovirals with the highest number of drug interactions with artemisinin-based combination therapies. QT prolongation is the most frequent adverse event, requiring closer ECG monitoring in patients on antiretroviral therapy. MHC patients therefore need careful monitoring of side effects during therapy and closer follow-up to ensure successful antimalarial treatment.

Nontuberculous mycobacteria infection is one of the most serious and difficult-to-treat complications in AIDS patients. Difficult microbiological diagnosis together with variable compliance to treatment, pharmacological interactions and intestinal malabsorption are the most frequent problems that can cause treatment failure. We report a case of a young HIV-infected man, AIDS presenter with disseminated non-tuberculous mycobacteria infection and immune reconstitution inflammatory syndrome, who failed antimycobacterial and antiretroviral treatment because of intestinal malabsorption. Clinical improvement was seen after intravenous administration of antimycobacterial drugs and following an adjustment of antiretroviral treatment due to virological failure. Intestinal malabsorption must be accounted for in cases of oral treatment failure in mycobacterial infections.

Vi è un’estesa sovrapposizione geografica tra malaria e infezione da HIV nell’Africa Sub-Sahariana e, in minor misura, nel Sud-Est Asiatico. In Europa e Nord America i casi di malaria nei pazienti HIV positivi sono limitati ai viaggiatori in aree malariche senza idonea profilassi. La co-infezione malaria-HIV (CMH) comporta un aumento della viremia e una riduzione del numero dei linfociti CD4+, l’incremento della parassitemia e della frequenza di gametocitemia persistente, più frequenti complicanze da malaria grave e mortalità più elevata. La CMH in gravidanza aumenta il rischio di complicanze perinatali (parto pre-termine, aumentata mortalità neonatale, anemia grave). Nella scelta del trattamento antimalarico è necessario tenere in considerazione le numerose interazioni farmacologiche con la terapia antiretrovirale. In generale gli inibitori delle proteasi e gli NNRTI sono i farmaci con il maggior numero di interazioni farmacologiche con le terapie di combinazione a base di derivati dell’artemisinina. L’allungamento del tratto QT è l’evento avverso più frequente e che richiede un monitoraggio ECG più attento nei pazienti in trattamento antiretrovirale. Il paziente con infezione da HIV necessita pertanto un attento monitoraggio degli effetti collaterali in corso di terapia e rivalutazione nelle settimane successive per assicurarsi l’efficacia del trattamento antimalarico., There is extensive geographical overlap between malaria and HIV infection in Sub-Saharan Africa and, to a lesser extent, Southeast Asia. In Europe and North America, malaria cases in HIV-positive patients are limited to travellers in malarial areas without appropriate prophylaxis. Malaria-HIV co-infection (MHC) results in increased viremia and reduced CD4+ counts, increased parasitaemia and frequency of persistent gametocytaemia, more frequent severe malaria complications and higher mortality. MHC in pregnancy increases the risk of perinatal complications (pre-term delivery, increased neonatal mortality, severe anaemia). Numerous drug interactions with antiretroviral therapy must be considered when choosing antimalarial treatment. In general, protease inhibitors and NNRTIs are the antiretrovirals with the highest number of drug interactions with artemisinin-based combination therapies. QT prolongation is the most frequent adverse event, requiring closer ECG monitoring in patients on antiretroviral therapy. MHC patients therefore need careful monitoring of side effects during therapy and closer follow-up to ensure successful antimalarial treatment.

Nontuberculous mycobacteria infection is one of the most serious and difficult-to-treat complications in AIDS patients. Difficult microbiological diagnosis together with variable compliance to treatment, pharmacological interactions and intestinal malabsorption are the most frequent problems that can cause treatment failure. We report a case of a young HIV-infected man, AIDS presenter with disseminated non-tuberculous mycobacteria infection and immune reconstitution inflammatory syndrome, who failed antimycobacterial and antiretroviral treatment because of intestinal malabsorption. Clinical improvement was seen after intravenous administration of antimycobacterial drugs and following an adjustment of antiretroviral treatment due to virological failure. Intestinal malabsorption must be accounted for in cases of oral treatment failure in mycobacterial infections.

We examine the effects that the modelling of a Boxy/Peanut (B/P) bulge will have on the estimates of the stellar gravitational potential, forces, orbital structure and bar strength of barred galaxies. We present a method for obtaining the potential of disc galaxies from surface density images, assuming a vertical density distribution (height function), which is let to vary with position, thus enabling it to represent the geometry of a B/P. We construct a B/P height function after the results from a high-resolution, N-body+SPH simulation of an isolated galaxy and compare the resulting dynamical model to those obtained with the commonly used, position-independent "flat" height functions. We show that methods that do not allow for a B/P can induce errors in the forces in the bar region of up to 40% and demonstrate that this has a significant impact on the orbital structure of the model, which in turn determines its kinematics and morphology. Furthermore, we show that the bar strength is reduced in the presence of a B/P. We conclude that neglecting the vertical extent of a B/P can introduce considerable errors in the dynamical modelling. We also examine the errors introduced in the model due to uncertainties in the parameters of the B/P and show that even for generous but realistic values of the uncertainties, the error will be noticeably less than that of not modelling a B/P bulge at all., Comment: Accepted for publication in MNRAS

We examine the effects that the modelling of a Boxy/Peanut (B/P) bulge will have on the estimates of the stellar gravitational potential, forces, orbital structure and bar strength of barred galaxies. We present a method for obtaining the potential of disc galaxies from surface density images, assuming a vertical density distribution (height function), which is let to vary with position, thus enabling it to represent the geometry of a B/P. We construct a B/P height function after the results from a high-resolution, N-body+SPH simulation of an isolated galaxy and compare the resulting dynamical model to those obtained with the commonly used, position-independent "flat" height functions. We show that methods that do not allow for a B/P can induce errors in the forces in the bar region of up to 40% and demonstrate that this has a significant impact on the orbital structure of the model, which in turn determines its kinematics and morphology. Furthermore, we show that the bar strength is reduced in the presence of a B/P. We conclude that neglecting the vertical extent of a B/P can introduce considerable errors in the dynamical modelling. We also examine the errors introduced in the model due to uncertainties in the parameters of the B/P and show that even for generous but realistic values of the uncertainties, the error will be noticeably less than that of not modelling a B/P bulge at all., Comment: Accepted for publication in MNRAS

Several inflationary models predict the possibility that the primordial perturbations of the density field may contain a degree of non-Gaussianity which would influence the subsequent evolution of cosmic structures at large scales. In order to study their impact, we use a set of three cosmological DM-only simulations starting from initial conditions with different levels of non-Gaussianity: f_NL=0,+/-100. More specifically, we focus on the distribution of galaxy clusters at different redshifts and, using suitable scaling relations, we determine their X-ray and SZ signals. Our analysis allows us to estimate the differences in the logN-logS and logN-logY due to the different initial conditions and to predict the cluster counts at different redshifts expected for future surveys (eROSITA and SPT). We also use a second set of simulations assuming a different cosmological scenario to estimate how the dependence on f_NL is degenerate with respect to other parameters. Our results indicate that the effects introduced by a realistic amount of primordial non-Gaussianity are small when compared to the ones connected with current uncertainties in cosmological parameters, particularly with sigma_8. However, if future surveys will be associated with optical follow-up campaigns to determine the cluster redshift, an analysis of the samples at z>1 can provide significant constraints on f_NL. In particular we predict that the SPT cluster survey will be able to detect ~1000 clusters at z>1 for the Gaussian case, with a difference of 15-20 per cent associated to f_NL=+/-100., Comment: 11 pages, 8 figures, 2 tables. Submitted to MNRAS

The description of the abundance and clustering of halos for non-Gaussian initial conditions has recently received renewed interest, motivated by the forthcoming large galaxy and cluster surveys, which can potentially yield constraints of order unity on the non-Gaussianity parameter f_{NL}. We present tests on N-body simulations of analytical formulae describing the halo abundance and clustering for non-Gaussian initial conditions. We calibrate the analytic non-Gaussian mass function of Matarrese et al.(2000) and LoVerde et al.(2008) and the analytic description of clustering of halos for non-Gaussian initial conditions on N-body simulations. We find excellent agreement between the simulations and the analytic predictions if we make the corrections delta_c --> delta_c X sqrt{q} and delta_c --> \delta_c X q where q ~ 0.75, in the density threshold for gravitational collapse and in the non-Gaussian fractional correction to the halo bias, respectively. We discuss the implications of this correction on present and forecasted primordial non-Gaussianity constraints. We confirm that the non-Gaussian halo bias offers a robust and highly competitive test of primordial non-Gaussianity., Comment: 11 pages, 12 figures. Small changes to match the version submitted to the journal on Feb 24 2009

Several inflationary models predict the possibility that the primordial perturbations of the density field may contain a degree of non-Gaussianity which would influence the subsequent evolution of cosmic structures at large scales. In order to study their impact, we use a set of three cosmological DM-only simulations starting from initial conditions with different levels of non-Gaussianity: f_NL=0,+/-100. More specifically, we focus on the distribution of galaxy clusters at different redshifts and, using suitable scaling relations, we determine their X-ray and SZ signals. Our analysis allows us to estimate the differences in the logN-logS and logN-logY due to the different initial conditions and to predict the cluster counts at different redshifts expected for future surveys (eROSITA and SPT). We also use a second set of simulations assuming a different cosmological scenario to estimate how the dependence on f_NL is degenerate with respect to other parameters. Our results indicate that the effects introduced by a realistic amount of primordial non-Gaussianity are small when compared to the ones connected with current uncertainties in cosmological parameters, particularly with sigma_8. However, if future surveys will be associated with optical follow-up campaigns to determine the cluster redshift, an analysis of the samples at z>1 can provide significant constraints on f_NL. In particular we predict that the SPT cluster survey will be able to detect ~1000 clusters at z>1 for the Gaussian case, with a difference of 15-20 per cent associated to f_NL=+/-100., Comment: 11 pages, 8 figures, 2 tables. Submitted to MNRAS

The description of the abundance and clustering of halos for non-Gaussian initial conditions has recently received renewed interest, motivated by the forthcoming large galaxy and cluster surveys, which can potentially yield constraints of order unity on the non-Gaussianity parameter f_{NL}. We present tests on N-body simulations of analytical formulae describing the halo abundance and clustering for non-Gaussian initial conditions. We calibrate the analytic non-Gaussian mass function of Matarrese et al.(2000) and LoVerde et al.(2008) and the analytic description of clustering of halos for non-Gaussian initial conditions on N-body simulations. We find excellent agreement between the simulations and the analytic predictions if we make the corrections delta_c --> delta_c X sqrt{q} and delta_c --> \delta_c X q where q ~ 0.75, in the density threshold for gravitational collapse and in the non-Gaussian fractional correction to the halo bias, respectively. We discuss the implications of this correction on present and forecasted primordial non-Gaussianity constraints. We confirm that the non-Gaussian halo bias offers a robust and highly competitive test of primordial non-Gaussianity., Comment: 11 pages, 12 figures. Small changes to match the version submitted to the journal on Feb 24 2009

Free-stream Mach number 14 to 16 experiments in a high Reynolds number hotshot-type wind tunnel with a sharp 9-deg cone model under relatively cold-wall conditions are presented that reveal the expected strong influence of Mach number and a unit Reynolds number effect similar to that obtained in conventional wind tunnels. Comparison of cone and hollow cylinder (i.e., equivalent to a flat plate) transition Reynolds numbers from several wind tunnels and ranges fails to reveal a conclusive picture concerning the relationship of cone and flat-plate transition Reynolds numbers. The effectiveness of spherical roughness in promoting premature boundary-layer transition is shown to decrease exponentially with increasing Mach number. The results compare favorably with the hypersonic extension proposed by Potter and Whitfield for their original correlation. It is shown that care must be exercised in selecting the physical roughness size at hypersonic speeds because of possible flow field distortion., Prepared in cooperation with ARO, Inc., Tullahoma, TN.