Electrospun polylactic acid non-woven mats incorporating silver nanoparticles

This research is focused on the influence of silver nanoparticles (AgNPs) on the spinnability, morphology and wetting properties of electrospun polylactic acid (PLA) non-woven mats. PLA was electrospun from a chloroform solution (4.7 % g/g) and a filament and beads morphology was obtained, the filaments having an average diameter of 1.25 μm. Interestingly, water contact angle measurements showed a contact angle of θ = 81°, an improvement relative to as-cast film which exhibited a contact angle of θ = 54°. When AgNP, of ca. 12 nm size, were incorporated at 1 % g/g relative to PLA weight, to the 4.7 % PLA-chloroform solution, and electrospun, the filaments diameter was greatly reduced to an average of 0.65 μm, and the density of polymer beads was also reduced. It is believed that the electric conductivity of silver enhanced the spinnability of the polymer solution. Strikingly, water contact angle measurements showed that the PLA/AgNP mats exhibited an angle as high θ = 134°. Increasing the solution concentration to 6.7 % g/g still produced a beads-and-filament morphology, but with larger filament diameters, probably due to an increase in solution viscosity. When AgNP were added (again at 1 % g/g relative to PLA weight), the occurrence of beads diminished and the average filament diameter decreased confirming the enhancement in spinnability by the AgNPs. Moreover, contact angles remained above 110° suggesting that the overall morphology is key to PLA's mats hydrophobic behavior and not only filament diameter. Finally, the non-woven mats were rather amorphous, as revealed by differential scanning calorimetry and X-ray scattering, due presumably to the quenching process associated with the electrospinning process. © 2014 Springer-Verlag Berlin Heidelberg.Thanks are due to MICINN, Spain (grant FIS2010-18069) for generous financial support. Thanks are due to BIPEDD-2: S2010-BMD-2457 Comunidad de Madrid, Spain, for providing the facilities to carry out the X-ray diffraction experiments. TPeer Reviewe

Trypanosoma cruzi infection in the human population of the Bolivian Chaco: Four serosurveys over a 26-year period (1987-2013)

Introduction: Chagas disease (CD) remains a public health concern in several Latin American countries. At global level, Bolivia has the highest CD burden and the Chaco region, in the southeast of the country, is the most affected area. We report the results of four serosurveys for Trypanosoma cruzi antibodies, carried out approximately ten years apart from each other, during the lapse 1987-2013, in different localities of the Bolivian Chaco. Methodology: Four cross-sectional surveys were conducted in various localities, mostly rural, of the Bolivian Chaco, during the period 1987-2013. Results: Although a reliable analysis of CD epidemiological trend is challenging, a partial reduction of anti-T. cruzi seroprevalence over the past four decades in the Bolivian Chaco may be assumed. In particular, in 1987 the exposure to T. cruzi in rural setting was universal since the first years of life, while it resulted gradually lower and age-dependent thereafter. Moreover, T. cruzi seroprevalence among women of reproductive age (15-45 years) has been persistently high in rural areas. Conclusions: T. cruzi transmission is still active and CD remains a concern throughout the Bolivian Chaco. More efforts are needed in order to achieve a sustainable interruption of vector-borne CD transmission in this area

A focus on selected perspectives of the NUMEN project

The use of double charge exchange reactions is discussed in view of their application to extract information that may be helpful to determinate the nuclear matrix elements entering in the expression of neutrinoless double beta decay half-life. The strategy adopted in the experimental campaigns performed at INFN - Laboratori Nazionali del Sud and in the analysis methods within the NUMEN project is briefly described, emphasizing the advantages of the multi-channel approach to nuclear reaction data analysis. An overview on the research and development activities on the MAGNEX magnetic spectrometer is also given, with a focus on the chosen technological solutions for the focal plane detector which will guarantee the performances at high-rate conditions

Mortality after surgery in Europe: a 7 day cohort study

Background: Clinical outcomes after major surgery are poorly described at the national level. Evidence of heterogeneity between hospitals and health-care systems suggests potential to improve care for patients but this potential remains unconfirmed. The European Surgical Outcomes Study was an international study designed to assess outcomes after non-cardiac surgery in Europe.Methods: We did this 7 day cohort study between April 4 and April 11, 2011. We collected data describing consecutive patients aged 16 years and older undergoing inpatient non-cardiac surgery in 498 hospitals across 28 European nations. Patients were followed up for a maximum of 60 days. The primary endpoint was in-hospital mortality. Secondary outcome measures were duration of hospital stay and admission to critical care. We used χ² and Fisher’s exact tests to compare categorical variables and the t test or the Mann-Whitney U test to compare continuous variables. Significance was set at p<0·05. We constructed multilevel logistic regression models to adjust for the differences in mortality rates between countries.Findings: We included 46 539 patients, of whom 1855 (4%) died before hospital discharge. 3599 (8%) patients were admitted to critical care after surgery with a median length of stay of 1·2 days (IQR 0·9–3·6). 1358 (73%) patients who died were not admitted to critical care at any stage after surgery. Crude mortality rates varied widely between countries (from 1·2% [95% CI 0·0–3·0] for Iceland to 21·5% [16·9–26·2] for Latvia). After adjustment for confounding variables, important differences remained between countries when compared with the UK, the country with the largest dataset (OR range from 0·44 [95% CI 0·19 1·05; p=0·06] for Finland to 6·92 [2·37–20·27; p=0·0004] for Poland).Interpretation: The mortality rate for patients undergoing inpatient non-cardiac surgery was higher than anticipated. Variations in mortality between countries suggest the need for national and international strategies to improve care for this group of patients.Funding: European Society of Intensive Care Medicine, European Society of Anaesthesiology