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Air pollution in cities, intensified by vehicular traffic emissions and reduced ventilation, poses a significant health risk. Obstacles, like solid or vegetation barriers, are being considered as strategies to reduce pollution exposure for pedestrians and nearby residents in street canyons. This study utilises wind tunnel experiments, to simulate a typical urban canyon with street intersections on both sides, in a 1:200 scale and an H / W = 0.5 , positioned perpendicular to the free stream wind flow. A passive scalar representing a vehicular pollutant is released along the length of the street canyon. Concentration measurements inside the canyon are performed to determine the effect of parked cars, boundary walls, hedges and trees on pollutant concentration exposure for pedestrians on the sidewalk. Results show that one circulating vortex is generated within the canyon, driving the pollutant to accumulate along the leeward (upwind) wall. Tightly parked cars, boundary walls and hedges, placed along the sidewalk near the leeward wall, can reduce pedestrian pollutant exposure by 15 %, 23 % and 11 % respectively along this sidewalk. Attributes such as obstacle height, surface roughness and porosity play a key role in their performance. However, trees, when placed in the same area, increase pedestrian pollutant exposure by 51 % and 17 % under dense and sparse tree arrangements, respectively. While a broader analysis that considers the variability of vegetation attributes (e.g., porosity, stand density) is desirable, this study remains crucial for validating numerical simulations and suggesting optimal urban measures to reduce pollution exposure for citizens. • Obstacles such as cars, hedges, and boundary walls improve air quality along sidewalks. • Spaced trees alter pollutant dispersion patterns, creating pollution hotspots. • Height and porosity of obstacles influence their pollution mitigation ability. • Findings potentially aids optimising obstacle choice to mitigate pollution hotspots. • Data aids validation of air quality numerical simulations at the pedestrian level. [ABSTRACT FROM AUTHOR]

Aim of this multicenter study was to evaluate the impact of reoperative cardiac surgery for type A acute aortic dissection (TAAAD) on early and long-term outcomes. Patients with history of previous cardiac surgery were included in group R while those undergoing first operation where included in group F. Kaplan-Meier analysis was used to evaluate long-term survival in the 2 groups. A total of 1472 patients were included in the analysis. Of these, 85 (5.8%) and 1387 (94.2%) were included in group R and F, respectively. Thirty-day mortality was 24% (20 patients) and 18% (249 patients) in groups R and F, respectively(P = 0.8). Kaplan-Meier survival at 10 and at 20-year was 51.5% and 30.2% in group R and 48% and 32% in group F (P = 0.368). Patients with a history of previous cardiac operations who develop TAAAD can undergo surgery with similar early and long-term outcomes compared to those at their first operation. [ABSTRACT FROM AUTHOR]

The systematic integration of landscape dimension into general and sector-focused planning policies is one of the European Landscape Convention crucial points. This aspect is still poorly implemented in Italy, where landscape is often conceived as a field of action separate from the territorial context. The article presents the outcomes of a multidisciplinary research aimed at integrating landscape dimension into sector-focused policies, namely retail policies, in the Autonomous Province of Trento (Trentino-Alto Adige Region, Italy). The local government recently reformed its territorial retail development policies so as to comply with European reform regulations and with national decrees regulating the programming of services. It implemented the sector’s liberalization, but it did not give up the territorial planning and the conservation of the landscape values. In this context, a research was developed to evaluate retail development scenarios, and, more specifically, the opportunity to plan a Gross Leasable Area of territorial relevance. Two methods were used: an indicator matrix to assess landscape quality and a mathematical model to assess population mobility preferences among retail structures. This integrated evaluation approach allowed to highlight both the “rights of the landscape” and those of potential buyers. The outcomes of the research have been recently adopted by the APT regulatory framework on retail planning. The evaluation process actually acted as a process of collective learning, supporting political decision-making. [ABSTRACT FROM AUTHOR]

Abstract Background to determine reliability and reproducibility of measurements of aortic annulus in 3D models printed from cardiovascular computed tomography (CCT) images. Methods Retrospective study on the records of 20 patients who underwent aortic valve replacement (AVR) with pre-surgery annulus assessment by CCT and intra-operative sizing by Hegar dilators (IOS). 3D models were fabricated by fused deposition modelling of thermoplastic polyurethane filaments. For each patient, two 3D models were independently segmented, modelled and printed by two blinded " manufacturers ": a radiologist and a radiology technician. Two blinded cardiac surgeons performed the annulus diameter measurements by Hegar dilators on the two sets of models. Matched data from different measurements were analyzed with Wilcoxon test, Bland-Altmann plot and within-subject ANOVA. Results No significant differences were found among the measurements made by each cardiac surgeon on the same 3D model (p = 0.48) or on the 3D models printed by different manufacturers (p = 0.25); also, no intraobserver variability (p = 0.46). The annulus diameter measured on 3D models showed good agreement with the reference CCT measurement (p = 0.68) and IOH sizing (p = 0.11). Time and cost per model were: model creation ∼10–15 min; printing time ∼60 min; post-processing ∼5min; material cost ∼1€. Conclusion 3D printing of aortic annulus can offer reliable, not expensive patient-specific information to be used in the pre-operative planning of AVR or transcatheter aortic valve implantation (TAVI). [ABSTRACT FROM AUTHOR]

Arterial hypertension represents a common complication of immunosuppressive therapy after liver transplantation (LT). The aim of the study is to evaluate the prevalence and risk factors associated with hypertension after LT. From a cohort of 323 cirrhotic patients who underwent LT from 2008 to 2012, 270 patients were retrospectively evaluated, whereas 53 (16.4%) patients deceased. Hypertension was defined as blood pressure ≥140/90 mm Hg in at least two visits and/or the need for antihypertensive therapy. The prevalence of hypertension was 15% before LT and significantly increased up to 53% after LT ( P < .001). Mean follow-up was 43 ± 19 months. In normotensive (NT) subjects at baseline, 35.9% developed sustained hypertension after LT, whereas 15.2% developed transient hypertension within the first month after LT, and then returned NT. The development of sustained hypertension after LT was related to the mammalian target of rapamycin inhibitor treatment (odds ratio [OR], 4.02; 95% confidence interval [CI], 1.26–13.48; P = .02), alcoholic cirrhosis before LT (OR, 3.38; 95% CI, 1.44–8.09; P = .005), and new-onset hepatic steatosis after LT (OR, 2.13; 95% CI, 1.10–4.11; P = .02). Tacrolimus, the etiology and severity of liver disease, and other immunosuppressive regimens were not related to the development of hypertension after LT. In our cohort, the prevalence of arterial hypertension has increased up to 53% after LT, and metabolic comorbidities and immunosuppressive treatment with mammalian target of rapamycin inhibitors are the risk factors for the development of hypertension after LT. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate the impact of SUVmax fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) measured in the primary tumor, pelvic and para-aortic node with disease-free survival (DFS) and overall survival (OS) in patients with locally advanced cervical cancer. Methods and Materials: A total of 92 patients with histological diagnosis of locally advanced cervical cancer are treated with radiochemotherapy plus brachytherapy boost from January 2008 to April 2014 in our Institution. A pretreatment FDG-PET/CT for staging and radiotherapy planning was performed, and the value of SUVmax measured in primary tumor and positive nodes was related to DFS and OS. Results: Univariate analysis showed that DFS is related to FDG-PET/CT positive para-aortic nodes (P = 0.01), International Federation of Gynecology and Obstetrics (FIGO) stage of disease (P = 0.01), and primary tumor SUVmax (P = 0.02), and OS is related to positive paraaortic nodes (P = 0.01) and primary tumor SUVmax (P = 0.02). In multivariate analysis, DFS is modified by FDG-PET/CT positive para-aortic lymph nodes, stage and high T SUVmax (P = 0.02; P = 0.003; P = 0.04), but the only worse prognostic factor of OS is the high SUVmax in the primary tumor (P = 0.01). Conclusions: We found that T SUVmax, stage, and para-aortic lymph node status assessed by FDG-PET were independent prognostic factors of DFS, whereas only T SUVmax correlated with OS. [ABSTRACT FROM AUTHOR]

We study the dynamics of a naturally ventilated room in which a point source provides a steady source of buoyancy and which is affected by an opposing unsteady wind. The wind is modelled as a stochastic forcing, which aims at simulating realistic velocity fluctuations as observed in the lower atmosphere. Our main finding is the occurrence of a "noise-induced transition", namely a structural change of the mean behaviour of the system: the warm–cold air interface does not fluctuate around the elevation exhibited when wind is constant, but oscillations occur around a new (significantly lower) interface elevation. We provide the physical explanation for such a counter-intuitive behaviour and show its dependence on (i) wind characteristics (intensity and timescale of fluctuations) and (ii) relative strength of wind over thermal loads. A realistic example case shows that the behaviour highlighted here has potentially major implications in the design and management of naturally ventilated buildings. • Topic: natural ventilation of rooms (point buoyancy source) forced by stochastic wind. • We compare the system response to stochastic and constant winds (same mean velocity). • Mean configurations attained under constant and fluctuating wind are very different. • Wind fluctuations induce a worsening of the ventilation performance of the room. [ABSTRACT FROM AUTHOR]

Nitrogen dioxide (NO 2) is an important air pollutant due to its adverse effects on human health. Yet, current evidence on the association between NO 2 and the risk of breast cancer lacks consistency. In this study, we investigated the association between long-term exposure to NO 2 and breast cancer risk in the French E3N cohort study. Association of breast cancer risk with NO 2 exposure was assessed in a nested case-control study within the French E3N cohort including 5222 breast cancer cases identified over the 1990–2011 follow-up period and 5222 matched controls. Annual mean concentrations of NO 2 at participants' residential addresses for each year from recruitment 1990 through 2011, were estimated using a land use regression (LUR) model. Multivariable conditional logistic regression models were used to compute odds ratios (ORs) and their 95% confidence intervals (CIs). Additional analyses were performed using NO 2 concentrations estimated by CHIMERE, a chemistry transport model. Overall, the mean NO 2 exposure was associated with an increased risk of breast cancer. In all women, for each interquartile range (IQR) increase in NO 2 levels (LUR: 17.8 μg/m3), the OR of the model adjusted for confounders was 1.09 (95% CI: 1.01–1.18). The corresponding OR in the fully adjusted model (additionally adjusted for established breast cancer risk factors) was 1.07 (95% CI: 0.98–1.15). By menopausal status, results for postmenopausal women were comparable to those for all women, while no association was observed among premenopausal women. By hormone receptor status, the OR of estrogen receptor positive breast cancer = 1.07 (95% CI: 0.97–1.19) in the fully adjusted model. Additional analyses using the CHIMERE model showed slight differences in ORs estimates. The results of this study indicate an increased risk of breast cancer associated with long-term exposure to NO 2 air pollution. Observing comparable effects of NO 2 exposure estimated by two different models, reinforces these findings. [Display omitted] • NO 2 levels were estimated over a 22 years period, by two exposure assessment models. • Breast cancer risk was increased in association with exposure to NO 2 air pollution. • By menopausal status, the associations appear to be limited to postmenopausal women. • NO 2 air pollution was positively associated with risk of ER + breast cancer. • Consistent associations were observed for the two exposure assessment methods. [ABSTRACT FROM AUTHOR]

Background: Head-to-head comparisons of devices for transcatheter aortic valve implantation (TAVI) are mostly limited to 2-arm studies so far. The aim of this study was to compare simultaneously outcomes of the most used, second- and third-generation transcatheter aortic valves in a real-world population. Methods: A total of 2728 patients undergoing TAVI with different second- and third-generation devices, and enrolled in the multicenter, prospective OBSERVANT II study (Observational Study of Effectiveness of TAVI With New Generation Devices for Severe Aortic Stenosis Treatment) from December 2016 to September 2018 were compared according to the transcatheter aortic valve received. Outcomes were adjudicated through a linkage with administrative databases, and adjusted using inverse propensity of treatment weighting. The primary end point was the composite of all-cause death, stroke and rehospitalization for heart failure at 1-year. Rates were reported consecutively for Evolut R, Evolut PRO, SAPIEN 3, ACURATE neo, and Portico groups. Results: The primary end point did not differ among groups (23.9% versus 24.7% versus 21.5% versus 23.7% versus 27.4%, respectively, P =0.56). Permanent pacemaker implantation was significantly lower for patients receiving SAPIEN 3 (19.9% versus 19.3% versus 12.5% versus 14.7% versus 22.1%, respectively, P <0.01) at 1 year. The SAPIEN 3 had lower rates of paravalvular regurgitation (moderate-to-severe grade 10.1% versus 5.0% versus 2.1% versus 13.1% versus 10.8%, respectively, P <0.01) but higher transprosthetic gradients (median mean gradients 7.0 versus 6.0 versus 10.0 versus 7.0 versus 8.0 mm Hg, respectively, P <0.01) after TAVI. Conclusions: Data from real-world practice showed low and comparable rates of complications after TAVI considering all the available devices. Patients receiving SAPIEN 3 valve had lower rates of paravalvular regurgitation and permanent pacemaker implantation, but higher transprosthetic gradients. [ABSTRACT FROM AUTHOR]

Liver transplantation is the successful treatment of end-stage liver disease; however, the ischaemia-reperfusion injury still jeopardizes early and long-term post-transplant outcomes. In fact, ischaemia-reperfusion is associated with increased morbidity and graft dysfunction, especially when suboptimal donors are utilized. Strategies to reduce the severity of ischaemia-reperfusion can be applied at different steps of the transplantation process: organ procurement, preservation phase or before revascularization. During the donor procedure, preconditioning consists of pre-treating the graft prior to a sustained ischaemia either by a transient period of ischaemia-reperfusion or administration of anti-ischaemic medication, although a multi-pharmacological approach seems more promising. Different preservation solutions were developed to maintain graft viability during static cold storage, achieving substantial results in terms of liver function and survival in good quality organs but not in suboptimal ones. Indeed, preservation solutions do not prevent dysfunction of poor quality organs and are burdened with inadequate preservation of the biliary epithelium. Advantages derived from either hypo- or normothermic machine perfusion are currently investigated in experimental and clinical settings, suggesting a reconditioning effect possibly improving hepatocyte and biliary preservation and resuscitating graft function prior to transplantation. In this review, we highlight acquired knowledge and recent advances in liver graft preconditioning, preservation and reconditioning. [ABSTRACT FROM AUTHOR]

Background Albeit accepted in the trauma setting, use of peri-hepatic gauze packing has been rarely reported during liver transplantation. Aims To assess the results of packing in liver transplantation. Methods We reviewed clinical characteristics, intraoperative events and postoperative outcome of consecutive adult liver transplantation recipients between 2003 and 2013. Patients treated with packing were compared to no-packing patients and to matched controls selected using a propensity score. Results Of 1396 recipients, 107 were treated with packing for peri-hepatic bleeding (76.6%), allograft damage (12.1%) or partial outflow obstruction (11.2%). Urgent reoperation for ongoing haemorrhage was required in 6 (5.6%). Correction of haemodynamic and coagulation parameters was constantly achieved. Overall, patient (90% vs. 98%, p < 0.001) and graft (83.2% vs. 94.7%, p < 0.001) 3-month survival was significantly reduced in packing patients. However, after matching, no significant difference was observed in patient (89.3% vs. 95.2%, p = 0.12) and graft (83.5% vs. 92.2%, p = 0.06) 3-month survival. Patient survival was associated with recipient age (HR 2.59; p = 0.04) and donor age × recipient MELD (HR 2.04; p = 0.02), but not with packing (HR 1.81; p = 0.29). Conclusions In our experience, packing was a valuable adjunct to conventional means of haemostasis during liver transplantation and, after accounting for confounding covariates, was not associated with inferior outcomes. [ABSTRACT FROM AUTHOR]

Breathability in dense building arrays with packing densities similar to those of typical European cities is investigated using laboratory measurements and numerical simulations. We focus on arrays made up by regularly spaced square buildings forming a network of streets with right-angle intersections. It is shown that breathability can be evaluated using building ventilation concepts (mean flow rate and age of air) and from vertical mean and turbulent fluxes quantifiable through a bulk exchange velocity. Mean age of air reveals that varying wind angles result in different ventilation, which we explain through mean flow streamlines and exchange velocity. For low wind angles (wind direction almost parallel to the axes of half of the streets of the network), vertical transfer and mean transversal transfers are at minimum and removal of pollutants is associated with mean longitudinal fluxes. Larger wind angles result in better ventilation due to an increase of transversal fluxes and vertical exchange. The latter, for which a formulation is derived, shows a non-negligible contribution of the mean flow which increases with increasing wind angle. Ventilation conditions can be further altered by small differences in the array geometry. These observations are useful for the development of simple urban dispersion models. [ABSTRACT FROM AUTHOR]

Background The effect of gender on patients with aortic stenosis undergoing transcatheter aortic valve implantation (TAVI) remains to be defined. Methods MEDLINE, Cochrane Library, and Scopus databases were searched for articles describing sex differences in baseline characteristics, procedures, and outcomes. All-cause death at follow-up of at least 1 year was the primary end point, and the independent effect of female gender was evaluated with pooled analysis using a random-effect model and with meta-regression. Results Six studies with 6,645 patients were included, half of them being women presenting with lower European System for Cardiac Operative Risk Evaluation (EuroSCORE) compared with men. At 30 days, more frequent major vascular complications and major and life-threatening bleeding occurred in women, with lower rates of moderate to severe aortic regurgitation, whereas 30-day mortality was similar. After a median follow-up of 365 days (range, 365 to 730 days) all-cause mortality was 24.0% in women and 34.0% in men. A pooled analysis of the multivariable approach found female gender was significantly related to a lower risk of death (odds ratio, 0.82; 95% CI, confidence interval, 0.73 to 0.93; I 2 = 0%). A meta-regression analysis showed age, ejection fraction, previous cardiovascular accident, renal insufficiency, and access site did not influence these data. Conclusions Female patients undergoing TAVI present with a lower burden of comorbidities. The counterbalance between higher rates of vascular complications but lower of valve regurgitation may explain the reduced risk for women after TAVI, independently from baseline features and access site. [ABSTRACT FROM AUTHOR]

Background Occult hepatitis B virus infection is defined as detectable HBV-DNA in liver of HBsAg-negative individuals, with or without detectable serum HBV-DNA. In deceased liver donors, results of tissue analysis cannot be obtained prior to allocation for liver transplantation. Aims we investigated prevalence and predictability of occult hepatitis B using blood markers of viral exposure/infection in deceased liver donors. Methods In 50 consecutive HBsAg-negative/anti-HBc-positive and 20 age-matched HBsAg-negative/anti-HBc-negative donors, a nested-PCR assay was employed in liver biopsies for diagnosis of occult hepatitis B according to Taormina criteria. All donors were characterized for plasma HBV-DNA and serum anti-HBs/anti-HBe. Results In liver tissue, occult hepatitis B was present in 30/50 anti-HBc-positive (60%) and in 0/20 anti-HBc-negative donors ( p < 0.0001). All anti-HBc-positive donors with detectable HBV-DNA in plasma ( n = 5) or anti-HBs > 1,000 mIU/mL ( n = 5) eventually showed occult infection, i.e, 10/30 occult hepatitis B-positive donors which could have been identified prior to transplantation. In the remaining 40 anti-HBc-positive donors, probability of occult infection was 62% for anti-HBe-positive and/or anti-HBs ≥ 58 mIU/mL; 29% for anti-HBe-negative and anti-HBs < 58 mIU/mL. Conclusions In deceased donors, combining anti-HBc with other blood markers of hepatitis B exposure/infection allows to predict occult hepatitis B with certainty and speed in one third of cases. These findings might help refine the allocation of livers from anti-HBc-positive donors. [ABSTRACT FROM AUTHOR]

INTRODUCTION Left-sided portal hypertension is a rare clinical condition most often associated with a pancreatic disease. In case of hemorrhage from gastric fundus varices, splenectomy is indicated. Commonly, the operation is carried out by laparotomy, as portal hypertension is considered a relative contraindication to laparoscopic splenectomy (LS). Although some studies have reported the feasibility of the laparoscopic approach in the setting of cirrhosis-related portal hypertension, experience concerning LS in left-sided portal hypertension is lacking. PRESENTATION OF CASE A 39-year-old man was admitted to the Emergency Department for haemorrhagic shock due to acute hemorrhage from gastric fundus varices. Diagnostic work up revealed a chronic pancreatitis-related splenic vein thrombosis causing left-sided portal hypertension with gastric fundus varices and splenic cavernoma. Following splenic artery embolization (SAE), the case was successfully managed by LS. DISCUSSION The advantages of laparoscopic over open splenectomy include lower complication rate, quicker recovery and shorter hospital stay. Splenic artery embolization prior to LS has been used to reduce intraoperative blood losses and conversion rate, especially in complex cases of splenomegaly or cirrhosis-related portal hypertension. We report a case of complicated left-sided portal hypertension managed by LS following SAE. In spite of the presence of large varices at the splenic hilum, the operation was performed by laparoscopy without any major intraoperative complication, thanks to the reduced venous pressure achieved by SAE. CONCLUSION Splenic artery embolization may be a valuable adjunct in case of left-sided portal hypertension requiring splenectomy, allowing a safe dissection of the splenic vessels even by laparoscopy. [ABSTRACT FROM AUTHOR]

Objectives Patient selection is crucial to achieve good outcomes and to avoid futile procedures in patients undergoing transcatheter aortic valve replacement. The aim of this multicenter retrospective study was to identify independent predictors of 1-year mortality in patients surviving after transapical transcatheter aortic valve replacement. Methods We analyzed data from the Italian registry of transapical transcatheter aortic valve replacement that includes patients undergoing operation in 21 centers from 2007 to 2012. Futility was defined as mortality within 1 year after transapical transcatheter aortic valve replacement in patients surviving at 30 days. Thirty-day survivors were divided in 2 groups: futility (group F) and nonfutility (group NF). Cox proportional hazard regression analysis was performed to identify independent predictors of futility. Results We analyzed data from 645 patients with survival of 30 days or more after transapical transcatheter aortic valve replacement. Groups F and NF included 60 patients (10.8%) and 585 patients (89.2%), respectively. Patients in group F were more likely to have insulin-dependent diabetes (15% vs 7.2%, P = .03), creatinine 2.0 mg/dL or greater or dialysis (18.3% vs 8.2%, P = .01), logistic European System for Cardiac Operative Risk Evaluation greater than 20% (66.7% vs 50.3%, P = .02), preoperative rhythm disorders (40% vs 25.3%, P = .03), critical preoperative state (8.3% vs 1.8%, P = .002), and left ventricular ejection fraction less than 30% (15% vs 2.9%, P < .001). The multivariate analysis identified the following as independent predictors of futility: insulin-dependent diabetes (odds ratio, 3.1; P = .003), creatinine 2.0 mg/dL or greater or dialysis (odds ratio, 2.52; P = .012), preoperative rhythm disorders (odds ratio, 1.88; P = .04), and left ventricular ejection fraction less than 30% (odds ratio, 4.34; P = .001). Conclusions According to our data, among patients undergoing transapical transcatheter aortic valve replacement, those with insulin-dependent diabetes, advanced chronic kidney disease, rhythm disorders, and low left ventricular ejection fraction have a higher risk to undergo futile procedures. [ABSTRACT FROM AUTHOR]

This study presents the performances of an inverse modelling approach aiming to identify position and emission rate of a localised pollutant source placed within a city district. To that purpose we combine wind tunnel experiments and an urban dispersion model. Experiments are performed in an idealised urban canopy, made up of regularly spaced blocks, and provide the pollutant concentration field downwind from the source within the canopy. The urban dispersion model, named SIRANE, is an operational model that simulates the main mechanisms governing the pollutant transfer within a network of streets. [ABSTRACT FROM AUTHOR]

We test the reliability of an inverse model to estimate the amount of mass released instantaneously by a source of pollutant in a turbulent boundary layer. To that purpose we use wind tunnel experiments simulating the dispersion of puffs due to the impulsive release of pollutant. For each of these emissions we recorded time dependent signals at fixed receptors. These single signals have been used as input data for an inverse dispersion model in order to evaluate its error in estimating the real emission of pollutant. The inversion has been also performed using the ensemble average of the 100 signals as input data. The comparison of both approaches allows us to discuss the reliability of an atmospheric dispersion inverse model in real situations. [ABSTRACT FROM AUTHOR]

Abstract: Background: To generate a robust predictive model of Early (3 months) Graft Loss after liver transplantation, we used a Bayesian approach to combine evidence from a prospective European cohort (Liver-Match) and the United Network for Organ Sharing registry. Methods: Liver-Match included 1480 consecutive primary liver transplants performed from 2007 to 2009 and the United Network for Organ Sharing a time-matched series of 9740 transplants. There were 173 and 706 Early Graft Loss, respectively. Multivariate analysis identified as significant predictors of Early Graft Loss: donor age, donation after cardiac death, cold ischaemia time, donor body mass index and height, recipient creatinine, bilirubin, disease aetiology, prior upper abdominal surgery and portal thrombosis. Results: A Bayesian Cox model was fitted to Liver-Match data using the United Network for Organ Sharing findings as prior information, allowing to generate an Early Graft Loss-Donor Risk Index and an Early Graft Loss-Recipient Risk Index. A Donor-Recipient Allocation Model, obtained by adding Early Graft Loss-Donor Risk Index to Early Graft Loss-Recipient Risk Index, was then validated in a distinct United Network for Organ Sharing (year 2010) cohort including 2964 transplants. Donor-Recipient Allocation Model updating using the independent Turin Transplant Centre dataset, allowed to predict Early Graft Loss with good accuracy (c-statistic: 0.76). Conclusion: Donor-Recipient Allocation Model allows a reliable donor and recipient-based Early Graft Loss prediction. The Bayesian approach permits to adapt the original Donor-Recipient Allocation Model by incorporating evidence from other cohorts, resulting in significantly improved predictive capability. [Copyright &y& Elsevier]

We use a Lagrangian stochastic micromixing model to predict the concentration fluctuations of a continuous release in a neutral boundary layer. We present the computational algorithm that implements the interaction by exchange with the conditional mean model and we compare the numerical solutions with the experimental values in order to evaluate the reliability of the model. The influence of the source size on the concentration probability density function in the near and far-field is discussed and some shortcomings of the model are pointed out. [ABSTRACT FROM AUTHOR]

Air pollution in cities, especially in existing urban canyons, poses a global significant long-term health risk to the urban population, and urban planners are faced with the challenge of increasing the transport of pollutants out of cities. In recent years, many research and review articles have explored passive methods of altering the urban canyon geometry using 'obstacles' that alter the dispersion of air flow in these canyons, thereby enhancing pollutant dispersion. These obstacles have been categorised (in previous review articles) into porous and non-porous barriers. Porous barriers include vegetated shrubs and trees, while non-porous barriers include parked cars, low boundary walls, roadside barriers, wind catchers and solar chimneys. This paper expands on previous reviews to highlight newer studies, their findings, and challenges in implementing these measures for existing urban canyons. In addition, it attempts to bring us one step closer to developing urban design guidelines that improve air quality in the urban environment. • Vast literature was obtained for porous obstacles, but fewer studies were done for non-porous obstacles. • Porous obstacles could enhance both dispersion and deposition effects if implemented well. • Non-porous obstacles can benefit from shape, configuration, and positioning to reduce pollutant exposure. • Concluding table sets a subjective starting point for urban planners to better relate obstacles with urban areas. [ABSTRACT FROM AUTHOR]

Objective: Although surgical aortic valve replacement (SAVR) is the treatment of choice for patients with aortic valve stenosis, transcatheter aortic valve replacement (TAVR) and sutureless aortic valve replacement (SU-AVR) have shown good results. The aim of our multicenter, propensity-matched study was to compare the clinical and hemodynamic outcomes of surgical SAVR, transapical TAVR (TA-TAVR), and SU-AVR. Methods: We analyzed data from 566 TA-TAVR, 349 SAVR, and 38 SU-AVR patients treated from January 2009 to March 2012. We used a propensity-matching strategy to compare on-pump (SAVR, SU-AVR) and off-pump (TA-TAVR) surgical techniques. The outcomes were analyzed using multivariate weighted logistic regression or multinomial logistic analysis. Results: In the matched cohorts, the 30-day overall mortality was significantly lower after SAVR than TA-TAVR (7% vs 1.8%, P = .026), with no differences in mortality between SU-AVR and TA-TAVR. Multivariate analysis showed SU-AVR to have a protective effect, although not statistically significant, against aortic regurgitation, pacemaker implantation, and renal replacement therapy compared with TA-TAVR. Compared with TA-TAVR, SAVR demonstrated significant protection against aortic regurgitation (odds ratio, 0.04; P < .001) and a trend toward protection against death, pacemaker implantation, and myocardial infarction. The mean transaortic gradient was 10.3 ± 4.4 mm Hg, 11 ± 3.4 mm Hg, and 16.5 ± 5.8 mm Hg in the TA-TAVR, SU-AVR, and SAVR patients, respectively. Conclusions: SAVR was associated with lower 30-day mortality than TA-TAVR. SAVR was also associated with a lower risk of postoperative aortic regurgitation compared with TA-TAVR. We did not find other significant differences in outcomes among matched patients treated with SAVR, SU-AVR, and TA-TAVR. [Copyright &y& Elsevier]

Rationale and Objectives: Ultrasonography (US) is becoming popular for the assessment of adiposity, but no one has studied this tool in the light of its potential limitations. Our purpose was to investigate the impact of technical conditions on the evaluation of abdominal fat by US. Materials and Methods: Forty-five healthy males and 45 healthy females were consecutively enrolled in the study, randomly assigned to three groups equally distributed by sex, and examined accordingly to three technical points: fasting state (before and after meal [A]), breathing (expiration and inspiration [B]), and US equipment from different generations: 2003 and 1998 (C). Two blinded radiologists performed US in the these opposite conditions, acquiring five parameters representative of subcutaneous and visceral adiposity in two times. Student's t-test and Lin's correlation coefficient were used for statistical analysis to assess differences in the measures as well as in inter- and intra-observer agreements. Results: The maximum and the only statistically significant changes were observed for intra-abdominal fat thickness regarding fasting state and breathing (Δ% = 24.1 ± 21.3 and Δ% = 9.2 ± 20.4, respectively; P < .0001). Reproducibility and repeatability, especially for visceral fat, were proved more stable in the following conditions: fasting state, expiration, and newer machine (2003). Conclusion: This article provides essential information and “range of confidence” for variations that can be expected from using different conditions in the measurement of abdominal adiposity by US to be carefully addressed as well as considered by US users and by researchers involving this technique in the field of body composition. [Copyright &y& Elsevier]

Abstract: INTRODUCTION: Chronic biliary obstruction consequence of a bile duct injury may require liver transplantation (LT) in case of secondary biliary cirrhosis, intractable pruritus or reiterate episodes of cholangitis. “Mass-forming” sclerosing cholangitis leading to secondary portal vein thrombosis and pre-sinusoidal portal hypertension has not been reported so far. PRESENTATION OF CASE: We present the case of a patient who underwent laparoscopic cholecystectomy for Mirizzi syndrome. The persistent bile duct obstruction due to a residual gallstone fragment was treated by a prolonged biliary stenting. Following repeated bouts of cholangitis, a fibrous centrohepatic scar developed, conglobating and obstructing the main branches of the portal vein and of the biliary tree. The patient developed secondary portal vein thrombosis and portal hypertension. After an extensive diagnostic work-up, including surgical exploration to rule out malignancy, the case was successfully managed by liver transplantation. DISCUSSION: Mass-forming sclerosis of the bile duct and biliary bifurcation may develop as a consequence of chronic biliary obstruction and prolonged stenting. Secondary portal vein thrombosis and pre-sinusoidal portal hypertension represents an unusual complication, mimicking Klatskin tumor. CONCLUSION: A timely and proper management of post-cholecystectomy complications is of mainstay importance. Early referral to a specialized hepato-biliary center is strongly advised. [Copyright &y& Elsevier]

Background: Transcatheter aortic valve implantation (TAVI) has been proposed as a therapeutic option for high-risk or inoperable patients with severe symptomatic aortic valve stenosis. The aim of this multicenter study was to assess early and medium term outcomes of transapical aortic valve implantation (TA-TAVI). Methods: From April 2008 through June 2012, a total of 774 patients were enrolled in the Italian Registry of Trans-Apical Aortic Valve Implantation (I-TA). Twenty-one centers were included in the I-TA registry. Outcomes were also analyzed according to the impact of the learning curve (first 50% cases versus second 50% cases of each center) and of the procedural volume (high-volume versus low-volume centers). Results: Mean age was 81.0 ± 6.7 years, mean logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) I, EuroSCORE II, and The Society of Thoracic Surgeons risk score were 25.6% ± 16.3%, 9.4% ± 11.0%, and 10.6% ± 8.5%, respectively. Median follow-up was 12 months (range, 1 to 44). Thirty-day mortality was 9.9% (77 patients). Overall 1-, 2-, and 3-year survival was 81.7% ± 1.5%, 76.1% ± 1.9%, and 67.6% ± 3.2%, respectively. Thirty-day mortality of the first 50% patients of each center was higher when compared with the second half (p = 0.04) but 3-year survival was not different (p = 0.64). Conversely, 30-day mortality at low-volume centers versus high-volume centers was similar (p = 0.22). At discharge, peak and mean transprosthetic gradients were 21.0 ± 10.3 mm Hg and 10.2 ± 4.1 mm Hg, respectively. These values remained stable 12 and 24 months after surgery. Conclusions: Transapical TAVI provides good results in terms of early and midterm clinical and hemodynamic outcomes. Thus it appears to be a safe and effective alternative treatment for patients who are inoperable or have high surgical risk. [Copyright &y& Elsevier]

This paper reviews recent findings in the field of flow and pollutant dispersion modelling around buildings and within complex urban geometries. Complexity is not only associated to the packing density of buildings, but originates also from building-height variability, buoyancy effects close to the building walls, traffic-produced turbulence and from the presence of vegetation. Recent results are discussed in light of progress made in operational urban dispersion models as a way forward for the application of those models in real scenarios. [ABSTRACT FROM AUTHOR]