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In recent years, the use of organic materials to infer conductivity in biomedical devices has received increasing attention. Typical inorganic semiconductors and conductors are rigid and expensive, usually require multiple processing steps and are unsuitable for biomedical applications. Electrochemically or chemically doped conjugated polymers help to overcome these problems due to their stability, low cost, light weight and excellent electrical and optical properties. The conducting polymer poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) is the material of choice for biomedical applications as it is water soluble, however, there are growing concerns around its stabilizer, PSS, due to its release of acidic products upon degradation in-vivo. Here, we report the successful synthesis of PEDOT nanoparticles using hyaluronic acid (HA) as a stabilizer via an oxidative miniemulsion polymerisation technique. This improves the bioactivity and hydrophilicity of nanoparticles. The effect of varying amounts of HA and different molar ratios of EDOT:TOS has been studied and their role in the conductive and morphological properties of final nanoparticles has been fully elucidated. Furthermore, bioactivity and biocompatibility of the nanoparticles are demonstrated for customizable in vivo applications. Nanoparticles were found to have a conductivity up to 10 times greater than pristine PEDOT:PSS with increased addition of oxidant. The proposed easy-to-manufacture approach, along with the highlighted superior properties, expands the potential of conductive polymers in future customizable biological applications such as tissue scaffolds, nerve conduits and cardiac patches and represents a real breakthrough from the current state of the art.

Thin copper films with thickness ∼28 nm deposited on SiO2 substrate with the vacuum electron beam evaporation method and treated by UV-ozone are studied. It was found that a UV-ozone treatment of the copper film causes rapid formation of the thin ∼3-4 nm oxide film. XPS analysis showed that CuO oxide predominates in this film. The formed oxide film effectively protects the copper against the following oxidation. The presented method of UV-ozone treatment is a simpler and cheaper approach compared to many other ways to form protective coatings of copper to preserve its functional properties. This method can be useful in nanoelectronic, nanooptical, and biosensors applications.

Surgical outcomes may be associated with hospital volume and the influence of volume on minimally invasive liver surgery (MILS) is not known.Patients entered into the prospective registry of the Italian Group of MILS from 2014 to 2018 were considered. Only centres with an accrual period of at least 12 months and stable MILS activity during the enrolment period were included. Case volume was defined by the mean number of minimally invasive liver resections performed per month (MILS/month).A total of 2225 MILS operations were undertaken by 46 centres; nine centres performed more than two MILS/month (1376 patients) and 37 centres carried out two or fewer MILS/month (849 patients). The proportion of resections of anterolateral segments decreased with case volume, whereas that of major hepatectomies increased. Left lateral sectionectomies and resections of anterolateral segments had similar outcome in the two groups. Resections of posterosuperior segments and major hepatectomies had higher overall and severe morbidity rates in centres performing two or fewer MILS/month than in those undertaking a larger number (posterosuperior segments resections: overall morbidity 30·4 versus 18·7 per cent respectively, and severe morbidity 9·9 versus 4·0 per cent; left hepatectomy: 46 versus 22 per cent, and 19 versus 5 per cent; right hepatectomy: 42 versus 34 per cent, and 25 versus 15 per cent).A volume-outcome association existed for minimally invasive hepatectomy. Complex and major resections may be best managed in high-volume centres.Los resultados quirúrgicos pueden estar relacionados con el volumen de casos del hospital, pero no se conoce la influencia en la cirugía mínimamente invasiva del hígado (minimally‐invasive liver surgery, MILS). MÉTODOS: Se incluyeron los pacientes registrados en el registro prospectivo del grupo italiano de MILS desde 2014 a 2018. Solo se consideraron centros con extensión de ≥ 12 meses y actividad estable de MILS durante el periodo de reclutamiento. El volumen de casos se definió como el número de MILS efectuado por mes.Se llevaron a cabo un total de 2.225 MILS en 46 centros, 9 de ellos con 2 MILS/mes (n = 1.376 pacientes) y 37 centros con ≤ 2 MILS/mes (n = 849). La proporción de resecciones de segmentos anterolaterales disminuyó con el volumen de casos, mientras que la proporción de hepatectomías mayores aumentó. Los resultados para ambos grupos fueron similares en las seccionectomías lateral izquierda y en las resecciones del segmento anterolateral. Las resecciones del segmento posterosuperior y las hepatectomías mayores presentaron tasas más altas de morbilidad global y morbilidad grave en centros que realizaban ≤ 2 MILS/mes que en los que realizaban 2 MILS/mes (resecciones del segmento posterosuperior, morbilidad global 30,4 versus 18,7%, morbilidad grave 9,9 versus 4,0%; hepatectomía izquierda, 46,2 versus 22,0%, 19,2 versus 5,5%; hepatectomía derecha, 41,7 versus 33,8%, 25,0 versus 14.9%). CONCLUSIÓN: Se observó una asociación volumen‐resultado para la resección hepática mínimamente invasiva. Las resecciones complejas y mayores se pueden manejar mejor en centros de gran volumen.

Background Pancreas transplantation (PT) is the best option of care for patients with type I diabetes mellitus (T1DM). Methods From July 2005 to September 2014, we performed 27 PT from deceased donors (24 simultaneous pancreas-kidney transplantations [SPKT] and 3 pancreas transplantations alone) in a region with a high incidence of T1DM. Results Enteric drainage and systemic venous derivation were accomplished for all PT. Cold and warm ischemia times were 291 ± 70 minutes and 32 ± 9 minutes, respectively. The rate of early re-operations was 33%, mainly because of bleeding occurrence. Mean donor age was 31 ± 11 years; all patients had ABO compatibility and negative cross-match. With a mean follow-up time of 2.3 years, no death was registered. Graft survival of PT was 96.7%, with 1 graft loss in the SPKT group (3.7%) after acute rejection. Nine patients were submitted successfully to re-operation for no life-threatening complications within 30 post-operative days. No early or late episode of vascular thrombosis, pancreatitis, or pancreatic fistula was observed. All patients with a functioning graft had excellent metabolic control, with mean glycosylated hemoglobin level at last follow-up of 5.5% and median fasting glucose level of 95 ± 13 mg/dL, comparable to that in the non-diabetic population. Conclusions In our experience, PT is an excellent therapeutic solution for patients with T1DM. Despite fewer than 5 PT performed per year, graft and patient outcomes were similar to those in high-volume centers.

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. © 2013 Editrice Gastroenterologica Italiana S.r.l.

From the analysis of thermistor chain data recorded in a small clongatcd lake, compared with the results of numerical simulations, second vertical modes of the internal scichcs are shown to be active during more than twothirds of the whole stratifcd period, although no rcsonancc with the wind is observed. On the other hand, due to the wind pattern, transversal seiches (mainly the first vertical mode) are also usually excited and they somctimcs dominate. At the end of the stratified period, however, when the thermocline is very sharp, first vertical modeslongitudinal and transversal-are the only ones that are excited. Finally, due to the wind, a forced oscillation of the whole lake is excited. After Mortimer (1952), who brought up to date both the earlier descriptions of internal seiches in Loch Ness (Watson 1904) and their further interpretations (Schmidt 1908; Wedderburn 1907; Wedderburn and Young 1915), internal seiches have been recognized as an everyday feature of movement in stratified water systems subject to wind action (Marmorino and Mortimer 1978; Hutter 1993; Korgen 1995). Now, the relevance of the internal seiches is widely documented: the structure of the horizontal velocities in the water column may determine the regions where the shear is strong enough to create instabilities leading to turbulence that might facilitate the resuspension of bottom sediments (Wiegand and Chamberlain 1987); the periodic vertical displacements of the internal seiches can advect the suspended algal cells, forcing them to be exposed to variations in light intensity (Webster 1990; Gaedke and Schimmele 1990); and internal scichcs greatly support the flux path of the transference of energy from the wind to the hypolimnion (Imberger 1994).

Lake Onega is located in the southern part of Karelia, in the north-west of Russia. We report data taken by various limnigraphs and current meters and isolate, by spectral analysis, the most conspicuous barotropic periods of these signals. The analysis that follows is based on the linearized shallow-water equations, that are solved for the free oscillations and thus identify the eigenperiods and corresponding mode structures for this lake. Computational results are presented for a finite difference representation for these surface-seiche equations applied to the entire Lake Onega including its bays. The grid consists of quadratic elements of 1000 m side length corresponding to 9344 active cells. The emerging matrix eigenvalue problem exceeds the storage and compuational capacity of standard PCs or workstations and thus requires use of the approximate Lanczos procedure to isolate the first ten eigenperiods and corresponding mode structures of the barotropic seiches, lying between 12.1 and 2.2 h. Comparison of computational results and inferences from the water level and current-meter records, disclose satisfactory agreement between theory and observation.

Background & Aims: The appropriate allocation of grafts from HBcAb positive donors in liver transplantation is crucial, yet a consensus is still lacking. Methods: We evaluated this issue within Liver Match, a prospective observational Italian study. Data from 1437 consecutive, first transplants performed in 2007-2009 using grafts from deceased heart beating donors were analyzed (median follow-up: 1040 days). Of these, 219 (15.2%) were HBcAb positive. Sixty-six HBcAb positive grafts were allocated to HBsAg positive and 153 to HBsAg negative recipients. Results: 329 graft losses occurred (22.9%): 66 (30.1%) among 219 recipients of HBcAb positive grafts, and 263 (21.6%) among 1218 recipients of HBcAb negative grafts. Graft survival was lower in recipients of HBcAb positive compared to HBcAb negative donors, with unadjusted 3-year graft survival of 0.69 (s.e. 0.032) and 0.77 (0.013), respectively (log-rank, p = 0.0047). After stratifying for recipient HBsAg status, this difference was only observed among HBsAg negative recipients (log rank, p = 0.0007), 3-year graft survival being excellent (0.88, s.e. 0.020) among HBsAg positive recipients, regardless of the HBcAb donor status (log rank, p = 0.4478). Graft loss due to de novo HBV hepatitis occurred only in one patient. At Cox regression, hazard ratios for graft loss were: MELD (1.30 per 10 units, p = 0.0002), donor HBcAb positivity (1.56, p = 0.0015), recipient HBsAg positivity (0.43, p

A new one-dimensional numerical model that includes physical and biochemical processes has been developed. The biochemical processes, influenced by the lake dynamics, are required for forecasting water quality. The model is used to investigate the effects of different internal restoration measures, such as artificial mixing, input of oxygen and drainage of deep water. The model is applied to the Northern Basin of Lake Lugano, a Swiss-Italian border lake. The lake is highly eutrophic and chemically stratified throughout the year. The model was calibrated over one year and validated over a period of several years. The results agree well with the measured data. The coupled model reproduces the observed depth dependency of conductivity even during long simulation times. Due to the predominant mixing, decoupled physical models cannot maintain such gradients. The forecasting capabilities of the model are demonstrated for different case studies. The impact of restoration measures on water quality is rather small. Best results are achieved by reducing the external nutrient loading. Caution is recommended for internal measures as these have to be studied in greater detail.

The dynamic model Seemod developed at the EAWAG (Imboden and Gachter, 1978) and modified by Buhrer (Ambuhl and Buhrer, 1984), was adapted to the South Basin of the Lake of Lugano (Lago di Lugano). The model can predict the evolution of the state of the lake, described by the concentrations of dissolved phosphorus, dissolved oxygen particulate phosphorus and organic particulate carbon, in function of phosphorus load and taking into account physical and biochemical initial- and boundary conditions. The model parameters were chosen through measurements and calibrations by short runs. A 10-year-long simulation was done, starting from the data of 1980, and its results agree quite well with the measurements. Then some 15-year-long simulations were done, which corresponded to different scenarios related to a progressive linking up of sewage systems to water treatment plants. The model predicts that a satisfactory water quality level can only be reached by reducing the total phosphorus input to less than 25 t/a.

The hydrodynamic processes in the Lake of Lugano (Lago di Lugano) have been the object of three major measuring campaigns. The first during summer 1979 in the North Basin, the second in the autumn of 1984 in the South Basin and the last in 1989 again in the North Basin. It is expected that analysis of the collected data in conjunction with theoretical concepts will yield conclusive findings on the driving forces and hydrodynamics of the lake. Numerical models have been applied to the lake and the results have been compared to the measurements. Some models calculate the periods and distributions of amplitude, as well as surface velocities and internal seiches. Other models calculate wind-induced water circulation. Evidence is given to the peculiarities of the North Basin and the difficulties related with the depth-width ratio and with its deep chemical stratification.

By large scale circulation in lakes one means motions whose characteristic length scales extend over most parts or all of the water masses in a lake or the ocean. We present the governing equations and motivate, by means of a scale analysis, the various simplified versions of model equations that are in use in computational lake dynamics. This scale analysis not only permits rational deduction of the reduced equations, it equally provides a means of estimating their limitations. These are discussed as are the difficulties and the peculiarities inherent in the proposed equation sets. Special features of external and internal wave motions are studied. For barotropic oscillations of a lake system (Lake of Lugano) it is shown that substantial water masses are exchanged between the individual basins at the resonating periods. Baroclinic seiches of a three layer model in which each layer is effective within its own domain show (for the North basin of the Lake of Lugano) that mode structures may differ from layer to layer pointing at important modifications of classical interpretations of higher baroclinic wave dynamics. And in large lakes in the equatorial belt theβ-effect forces modifications of the classical understanding of seiche behavior. Long periodic oscillating features may be attributed to topographic Rossby waves or higher baroclinic internal gravity waves; the observational identification is, however, difficult because lack of spatial resolution of the data makes this identification non-unique. We, finally present results of a full nonlinear numerical baroclinic circulation model and demonstrate that it is able to reproduce the gross features of the immediate response to strong storms during a few days.

DURING ORTHOTOPIC human liver transplantation (OLT), postreperfusion tissue damage is associated with a significant increase in markers of cytolysis and cholestasis. In the early phases of reperfusion an increase in the steady-state levels of reactive oxygen species (ROS) was observed to correlate with the presence of cytolysis; nevertheless, the role of oxidative stress in causing and/or amplifying postreperfusion damage to human liver grafts has not as yet been conclusively defined. The topology and chronology of the damage in the transplanted liver may be described as an endothelial cell injury that appears in the late stage of cold ischemia, followed immediately after reperfusion by involvement of the whole liver vasculature with concomittant activation of Kupffer cells, which, together with endothelial cells, attract and trigger polymorphonuclear cells (PMNs), the major source of ROS. While oxidative stress occurring in the hepatic vasculature appears to be a primary cause of the reperfusion injury, the role of oxidative reactions in phagocyte recruitment and activation is not yet clear. Hence, patients scheduled for OLT in two different transplantation units were randomly divided into two groups: one group received an intravenous dose of an antioxidant supplement during surgery. During the first 2 hours of reperfusion, we monitored blood indices of oxidative stress and neutrophil activation. RECRUITMENT OF PATIENTS AND METHODS

The influence of steatosis and of other donor and recipient characteristics in affecting liver performance post-orthotopic liver transplantation (OLT) was evaluated in 311 consecutive liver transplantations made in 278 patients. Donor variables considered were age, sex, blood group, cause of death, intensive care unit (ICU) days, need for vasopressors, hepatic enzymes and bilirubin, total and warm ischemia time, and macro- and microvescicular steatosis. Recipient variables considered were age, sex, blood group, biliary output, and post-OLT peak levels of hepatic enzymes. Patient and graft survival were the main outcome indicators. In the multivariate analysis, macrovescicular steatosis involving 25% or more of the hepatocytes was the only variable independently associated with shorter patient survival (p0.05). Five (62.5%) of the eight livers with macrovescicular steatosis involving 25% or more of the hepatocytes incurred in a delayed non-function (DNF) and one (12.5%) in a primary non-function (PRNF). The incidence of DNF and PRNF in the group with macrovescicular steatosis involving less than 25% of the liver cells was 1.6% (p0.001) and 2.3%, respectively. Microvescicular steatosis of any degree was not associated with a worse prognosis. Macrovescicular steatosis involving 25% or more of the hepatocytes identifies marginal livers, the use of which significantly increases the risk of graft non-function post-OLT.

Transplenic decompression of esophageal varices by distal splenorenal shunt according to Warren (DSRS) aims to a selective detention of the esophago-gastric varices, also assuring an adequate portal perfusion and hypertensive state of the porto-mesenteric district. The DSRS though, should and must not be performed in emergency as a high mortality rate is registered in all cases of emergency porto-systemic derivations. A mortality risk is reported even during endoscopic sclerosis if performed in emergency compared to the elective procedure. The scope of our study was to test the validity of a new approach of the hemorrhagic cirrhotic patient: the end point was to stop the bleeding with Glypressin and deferred sclerotherapy, associating a selective shunt at 40-60 days. Out of 32 patients with esophago-gastric variceal bleeding, 8 were selected also for derivative surgery. Results show Glypressin as the first and best therapeutic approach. The drug in many cases stops bleeding or at least reduces the blood loss allowing an easier endoscopic sclerosis. Further sclerosis and/or surgical therapy may assure variceal eradication.

The three-dimensional, finite-difference model of R.L. Street (Stanford University) has been adapted at the simulation of wind-induced currents in the northern basin of the Lake of Lugano. The model makes use of complete Navier-Stokes equations and a dynamical algorithm to calculate the eddy viscosity. The model predictions are compared with data collected in the measure campaign of 1979.

A computational analysis of the periods and structure of surface seiches of the southern basin of Lake of Lugano and its experimental verification from three simultaneous water gauge recordings, mounted along the shores in Agno, Morcote and Riva S. Vitale, is given. The first five theoretical modes are calculated with a finite element code of the tidal equations; it yields the eigenperiods and co-range and co-tidal lines, which are graphically displayed and discussed in detail.

It has been found that increasing the gain band width of the voltage control circuit of a Van de Graaff accelerator greatly improves the obtainable energy resolution. The resulting resolution measured at 1 MeV proton energy is 60 eV fwhm. The circuitry and measuring techniques are described.

An absolute precision determination of the threshold energy for the T(p, n)3He reaction has been performed, using an improved type of target consisting of isotopically pure tritiated ice. The result ETh = 1019.00±0.10 keV is somewhat lower but more accurate than previous values. The Q value of the reaction thus obtained is Q = −763.77±0.08 keV. Published values of the maximum β-energy of tritium are reviewed. The neutron proton mass difference is given as 782.3±0.1 keV.

Several excited states of 28Si can be reached either by capture of protons by 27Al or by capture of α particles by 24Mg through resonant reactions whose total width is quite narrow. Thus it is possible to obtain very accurate values of the mass difference of 27Al24Mg or the Q value of the reaction 27 Al(p, α)Mg 24 by simply measuring the two resonance energies of the primary proton and α particle, respectively. It is found that there is a significant difference of about 7 keV between the values determined in this way and the Q value and mass differences listed in the tables of Everling et al. For the Q value this difference is more then 5 times the combined errors.

The following Q values have been measured absolutely: Q = 559 ± keV for 9 Be(p,d) 8 Be , Q = 92.6 ± 0.8 keV for 8 Be(α)α .

TISO 15 is an experimental, utility line interactive photovoltaic installation. It is intended for the collection of practical data related with the direct immission of photovoltaic electrical energy into a standard AC utility grid.

The desire to individualize instruction as class size increases is a growing problem to many teachers. An ever increasing challenge to teachers is varying classroom procedures and presentations, while keeping the daily routine interesting, exciting, and relevant to the individual student.