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Background The presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in human semen and its role in virus contagion and semen quality after recovery from coronavirus disease 2019 (COVID-19) is still unclear. Recent reports evidence that, after SARS-CoV-2 infection, male reproductive function and semen quality may be damaged. Aim To evaluate the semen parameters and inflammation of sexually active men following recovery from SARS-CoV-2 infection at 1 month and 3 months follow-up after the second negative nasopharyngeal swab. Materials and methods A prospective cross-sectional study on sexually active men recovered from SARS-CoV-2 infection was performed. For previously hospitalized COVID-19 patients, data on serum inflammatory markers were retrospectively collected. One month after the second SARS-CoV-2 negative nasopharyngeal swab and 3 months later, four biological fluid samples, namely saliva, pre-ejaculation urine, semen, and post-ejaculation urine, were collected. The occurrence of SARS-CoV-2 RNA in the specimen was evaluated in all the biological fluids collected by RT-PCR. Female partners were retested if any specimen was found to be SARS-CoV-2 positive. Semen parameters were evaluated according to the World Health Organization manual edition V. Furthermore, semen inflammation was assessed by quantification of semen leukocytes and interleukin-8 (IL-8) levels and evaluation of a panel of sperm cytokine levels by a two-step ELISA method. Results A total of 43 men were enrolled in the study. Three patients (7%) tested positive for at least one sample (one saliva; one pre-ejaculation urine; one semen and one post-ejaculation urine), so the next day new nasopharyngeal swabs were collected. The results from these 3 patients and their partners were all negative for SARS-CoV-2. At 1-month follow-up, 25% of the men with recent SARS-Cov-2 infections and proven healing were oligo-cryptoazoospermic, despite the absence of virus RNA in semen. Of the 11 men with semen impairment, 8 were azoospermic and 3 were oligospermic. Serum inflammatory markers (procalcitonin and C-reactive protein) were analyzed in previously hospitalized patients both at admission and at peak of infection. Levels at admission were statistically significantly higher in patients resulting in crypto-azoospermic with respect to those resulting in normozoospermic (p = 0.05; p = 0.03 and p = 0.02, respectively) after healing. Oligo-crypto-azoospermia was significantly related to COVID-19 severity (P A total of 33 patients (76.7%) showed pathological levels of IL-8 in semen. Interleukin-1β and tumor necrosis factor-α levels were significantly negatively related to sperm total number and concentration, whereas interleukin-4 was correlated with sperm motility. At 3-months follow-up, 8/10 men with semen impairment showed an overall increase of semen parameters compared to levels assessed after 1 month. Of the 4 crypto-/azoo-spermic men 1 month after healing, 2 resulted oligozoospermic, 1 normozoospermic and only 1 remained azoospermic. Two of the 3 oligozoospermic men turned normozoozpermic. Semen cytokine levels remained elevated after 3 months, except for IL-6. Discussion and conclusion SARS-CoV-2 can be detected in saliva, urine, and semen in a small percentage of men who recovered from COVID-19. 25% of men who recovered from COVID-19 demonstrated oligo-crypto-azoospermia. Negative correlations between interleukin-1β and tumor necrosis factor-α and sperm number and the overall high levels of semen cytokines indicate a potential detrimental role of SARS-CoV-2 driven inflammation on spermatogenesis. An overall tendency to an improvement of semen parameters was found although a genital tract inflammatory condition appears to persist at least 3 months after COVID-19 recovery. Despite the low number of enrolled patients may limit the statistical power of study and the fact that the previous semen quality of these men was unknown, our results indicate that male of reproductive age recovering from COVID-19 deserve accurate follow-up for their fertility status.

Two different full-field techniques are here used to investigate the heat sources and dissipation sources that compare onto the surface of a composite laminate under fatigue load. The material here studied is a glass fibre reinforced epoxy laminate employed in the field of wind turbine. During fatigue tests, 8-bit (256 grey levels) images and thermal images were acquired and elaborated to relate the hysteresis area and the heat sources, finding the energy of damage in three points of specimens. The data shows a clear intensification of dissipative phenomena just in that region where final failure is then registered.

In this paper an associative-parametric approach is proposed in order to model the mesh of an aeronautical concept starting from a set of high-level structural primitives. This approach allows the designer to carry out the geometric modelling and the automatic mesh generation within one software environment in a fast and interactive way. The structural optimisation process is then simplified, with a relevant man-hours saving. A lower number of data transfers between different software is, moreover, involved with less problems related to the data corruption. To assure orders of continuity higher than C0 between adjacent instances, a suitable mathematical description of the structural primitives has been proposed. This description assures the maintenance of the required continuity constraints when the mesh is modified. Appropriate schemes of dependences are identified to guarantee the automatic propagation of the modifications complying with the continuity constraints.

DIC (Digital Image Correlation) based methodology gives full field measure of the displacement using a well defined algorithm for matching the images of loaded and load free component, so that displacement in a plane can be evaluated for a certain number of grid reference points on the analysed surface. In this work, the authors present an application of DIC technique to analyse fatigue damage phenomena in two notched GFRC laminates under tensile load. Damage analysis based on optical DIC technique has been performed to detect the damaged areas on the specimen surface. The damage evolution and failure mechanism has been followed monitoring two parameters: the local hysteresis area of stress-strain cycles, the local stiffness variation.

This work presents a non-linear continuum damage mechanics model based on general thermodynamic framework developed by Lemaitre and Chaboche. The proposed model has been formulated to take into account the material damage evolution at different load levels and it allows the effect of the loading sequence to be included; by means of a recurrence formula derived for multilevel loading, complex load sequences can be considered. The fatigue test data for a hardened and tempered steel have been used to verify the model proposed in this paper and the results show a good agreement to predict fatigue life under complex load sequences.

In this article, a methodology to analyze the shear behavior of aluminum foam with closed cells is proposed. A biaxial load device was expressly designed and the elaboration with digital image correlation technique of the data acquired during the test with a charge coupled device (CCD) camera allowed determining the displacement and strain fields. This procedure made it possible to evaluate the procedure as suitable or not for conducting a shear characterization for metallic foam. The τ-γ curves obtained showed an initial elastic outline followed by the yield plateau, a peak load, and a rapid load drop.

In this work, a scheme of representation for aircraft structural concepts is identified. Based on this scheme, a parametric-associative geometrical modelling of the aeronautic structure, consisting in a quad-mapped mesh, is proposed. The mesh generation is based on a hierarchical scheme ensuring the one-to-one correspondence between mesh elements belonging to adjacent primitives. The automatic propagation of modifications is efficiently implemented according to well-defined schemes of dependence thanks to which the modifications involve only the concerned instances. This scheme is implemented in an original software, called MeshFEM and developed using C++, Matlab and the VTK library for 3D graphic visualisation.

During the high cycle fatigue of aluminium alloys, an energy dissipation occurs. This dissipation is hard to be estimated because of the high diffusivity of such alloys and the importance of the thermoelasticity effects in comparison with others standard metallic materials (e.g., steels). Nevertheless the study of the energy balance gives valuable information about the nature of deformation mechanisms facilitating the construction of constitutive models associated with the microplasticity and damage of the aluminium alloy. In this work, the different energies involved in the energy balance were deduced from two complementary imaging techniques. The dissipation and thermoelastic sources were derived from an infrared thermography system, while the deformation energy was estimated from a digital image correlation system. Three tests with various loading blocks were carried out and a comparison between deformation and dissipation energies was systematically performed. (C) 2009 Elsevier Ltd. All rights reserved.

A study of damage characterization of a GFRC laminate is presented here. Forty fatigue tests were executed and S – N curves traced. Two parameters were chosen to monitor damage evolution during each test: stiffness and dissipated energy per cycle. Moreover, the presence of three zones in graphs of processed data can be observed and it is evident that the most important structural transformations take place only in the very final part of life. Adopting a continuum mechanics approach, the degradation through the whole life in composite is evaluated and it is shown that the two parameters are strictly related to damage state of composite material. A method for predicting the remaining life in a GFRC is here proposed.

Over the 1st postoperative yr, distal splenorenal shunt (DSRS) in cirrhotic patients is followed by a reduction in portal perfusion resulting from a spontaneous opening of portal-systemic collaterals. This can influence plasma levels of insulin and glucagon. Fasting plasma glucose, insulin, C-peptide, and glucagon and their 5-h responses to a protein meal (which directly stimulates the hormone secretions) were measured before and 3 and 12 mo after DSRS in 10 cirrhotic patients. Hormone effectiveness and pancreatic alpha- and beta-cell sensitivities to ammonia (NH3), amino acids, and glucose were also calculated. Liver function and portal vein diameter were assessed before each study. Seven cirrhotic patients treated with injection sclerotherapy of esophageal varices served as a control group. Liver function did not deteriorate in either patient group. An increase in fasting glucagon (from 181 +/- 22 to 242 +/- 22 and 255 +/- 22 pg/ml, p = 0.02) and NH3 (from 57 +/- 8 to 84 +/- 11 and 97 +/- 14 micrograms/dl, p = 0.04) and a decrease in glucagon effectiveness (from 0.56 +/- 0.06 to 0.39 +/- 0.05 and 0.035 +/- 0.03, p = 0.047) and portal vein diameter (from 16.0 +/- 1.1 to 11.3 +/- 0.8 and 9.4 +/- 0.6 mm, p0.001) was found only in DSRS patients. The elevation in glucagon was correlated with that of NH3 at 3 mo (r = 0.83, p = 0.003) and with the reduction of portal vein diameter at 1 yr (r = -0.81, p = 0.005). In cirrhosis, DSRS does not influence insulin secretion or its plasma level and effectiveness.(ABSTRACT TRUNCATED AT 250 WORDS)

In this paper the possibility to employ the Digital Image Correlation (DIC) technique for the mechanical behaviour analysis of metallic foam was investigated. Image Correlation allowed to measure displacement and strain fields on closed and open cells aluminium foam specimens under two different loading conditions (compression and shear) and to characterise, with opportune calculation, information on the mechanical behaviour of foams. The adopted technique is suitable to conduct a deep analysis and also to appreciate the local heterogeneities that appear in a specimen during test. The parameters obtained with DIC analysis are confirmed by the global data obtained by testing machine proving the adopted methodology represents a valid tool for the study of these new materials.

Renal function, plasma renin activity, plasma aldosterone concentration and urine excretion of free norepinephrine were evaluated in 13 cirrhotics without previous or ongoing ascites and in 13 healthy subjects, after 6 days of controlled electrolyte intake (40 mmol of Na and 70 mmol of K per day) and during 24 h of recumbency. Plasma concentrations of the atrial natriuretic peptide (ANP) were also measured in 8 patients and 8 controls. Despite a low-normal filtered load of sodium (14.6 +/- 1.2 vs. 17.1 +/- 1.2 mmol/min), cirrhotic patients showed supernormal natriuresis (141.5 +/- 14.1 vs. 78.8 +/- 8.6 mmol/day; p0.001). Whereas the fractional excretion of sodium in these patients was twice that of controls (0.70 +/- 0.05 vs. 0.36 +/- 0.04%; p0.001), potassium excretion (42.5 +/- 2.7 vs. 43.1 +/- 2.7 mmol/day) and urine volume (1270 +/- 98 vs. 1452 +/- 148 ml/day) did not differ. In cirrhotics, plasma renin activity was reduced (0.50 +/- 0.12 vs. 1.39 +/- 0.33 ng/ml/h; p0.02), and plasma aldosterone concentration tended to be lower (66 +/- 10 vs. 86 +/- 9 pg/ml; p = 0.09), while urine norepinephrine excretion did not significantly differ from controls (961 +/- 120 vs. 782 +/- 43 ng/h). ANP was higher in patients than in controls (92 +/- 17 vs. 48 +/- 9 pg/ml; p0.05). Natriuresis was directly correlated with ANP (r = 0.69, p0.005) and ANP/plasma aldosterone ratio (r = 0.63; p0.01) in patients and healthy subjects taken together.(ABSTRACT TRUNCATED AT 250 WORDS)

An impaired autonomic nervous system activity has been described in liver cirrhosis (1,2). Namely, an enhanced sympatho-adrenergic activity has been found in patients with ascites, who also showed an impaired cardiovascular responsiveness to such an adrenergic hypertone (2). Moreover, in these patients the cardiovascular response to the administration of exogenous norepinephrine (1), as well as maneuvers stimulating the adrenergic activity (3), was impaired. Recently, abnormalities of vagal activity have also been described and related to the alcoholic etiology of liver disease (4). It has been suggested that vagal neuropathy may result in an inappropriate, non osmotic secretion of antidiuretic hormone, promoting the appearance of hyponatremia (4), an abnormality which is frequently detectable in advanced liver failure.

The efficacy of CDP-choline (1000 mg/die) administered for two 21-day treatment cycles, with a one-week wash-out period between them, was evaluated in out and in-patients suffering from mild to moderate brain aging. The study was performed on 237 fully evaluable patients with the use of the reduced geriatric scale of Plutchik and al., for clinical evaluation of the symptomatology. The clinical data obtained demonstrate that treatment with CDP-choline is able to determine an improvement of symptomatology since the 1st cycle of therapy (p less than 0.001), and a further improvement in the 2nd cycle (p less than 0.001). Particularly, the therapeutic effect of the 1st cycle is persistent in the intermediate wash-out period (suspension of treatment) with a further decrease, of symptomatology regarding some items of Plutchik's scale (p less than 0.01). Finally, treatment with CDP-choline 1000 mg/die for two 21-day cycles in 237 patients suffering from brain aging determined a statistically significant improvement of the cognitive and behavioural parameters taken into consideration: independence/autonomous life; human relations/social life; interest and attentive capacity; individual behaviour. Therefore citicoline is confirmed as a valid therapeutic remedy for the clinical, functional and social recovery of these patients.

A CDM (continuum damage mechanics) model for damage evaluation is here considered and applied to the study of two different typologies of notched and cylindrical specimens. The model presents some parameter and authors determined them in a previous work testing cylindrical and smooth specimens. Firstly fatigue characterization was conducted and the SN curves found. In order to evaluate the capability of CDM model to predict the sequence effect and to simulate a more realistic loading condition, tests with various loading blocks were carried on and in particular high-low, low-high and random blocks were applied to the three specimens considered. Model previsions showed good agreement with results for each geometry considered.

Several studies on Digital Image Correlation technique allowed this methodology to be recognised in the last decade as a welloptimised tool for mechanical experimental measures, but much work is to be done to apply DIC based analyses on advanced applications, such as fatigue damage studies and composite materials failure investigations. DIC based methodology gives direct measure of the displacement field using a well defined formulation of matching the images of loaded and load free component, so that displacement vectors can be evaluated for a certain number of grid reference points on the analysed surface. In this work, the authors present the latest research with this method, and analyse fatigue damage phenomena in GFRC laminates under tensile fatigue load employing notched and notch-free specimens. Damage analysis based on optical DIC technique has been performed to detect the damaged areas on the specimen surface and to follow failure mechanisms during lifetime; the damage evolution in composites was performed monitoring two parameters: the local hysteresis area of stress strain cycles, the local stiffness variation. These parameters are evaluated on a grid by means of DIC strain measurements during the entire fatigue life showing encouraging results.

Films of a dialkoxy poly( p -phenylenevinylene) (PPV) derivative bearing a bridged chain dialkoxy substituent on the aromatic rings (Bridged Dialkoxy PPV: BDA-PPV) were prepared via solvent casting and Langmuir–Blodgett (LB) techniques for applications in gas sensing devices. A description of the LB deposition of the sensing layers starting from an equimolar mixture of the polymer and arachidic acid is reported. Silicon substrates equipped with gold interdigitated electrodes have been used for both deposition procedures. In particular, the samples deposited by solvent casting evidence variation of the electrical conductivity when exposed to NO 2 oxidising agent at a working temperature of about 75 °C. They also exhibit selectivity towards NO 2 with respect to other different gases like carbon monoxide, nitrogen monoxide, ammonia and sulphur dioxide. On the contrary, LB multilayers, containing arachidic acid, have not shown any sensitivity towards all analysed gases.

OBJECTIVES: To compare simple enucleation (SE) and standard partial nephrectomy (SPN) in terms of surgical results in a multicenter dataset (RECORd Project). MATERIALS AND METHODS: patients treated with nephron sparing surgery (NSS) for clinical T1 renal tumors between January 2009 and January 2011 were evaluated. Overall, 198 patients who underwent SE were retrospectively matched to 198 patients who underwent SPN. The SPN and SE groups were compared regarding intraoperative, early post-operative and pathologic outcome variables. Multivariable analysis was applied to analyze predictors of positive surgical margin (PSM) status. RESULTS: SE was associated with similar WIT (18 vs 17.8 min), lower intraoperative blood loss (177 vs 221 cc, p = 0.02) and shorter operative time (121 vs 147 min; p < 0.0001). Surgical approach (laparoscopic vs. open), tumor size and type of indication (elective/relative vs absolute) were associated with WIT >20 min. The incidence of PSM was significantly lower in patients treated with SE (1.4% vs 6.9%; p = 0.02). At multivariable analysis, PSM was related to the surgical technique, with a 4.7-fold increased risk of PSM for SPN compared to SE. The incidence of overall, medical and surgical complications was similar between SE and SPN. CONCLUSIONS: Type of NSS technique (SE vs SPN) adopted has a negligible impact on WIT and postoperative morbidity but SE seems protective against PSM occurrence