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51.
Pietro Canepa Nazzareno Marignetti Umberto Rognoni Seba Calgari 《Water research》1988,22(12):1491-1494
The purpose of this work was to verify the combined application of membranes and adsorption processes to the treatment of vegetation waters coming from olive oil factories. The described pilot plant worked for about 6 months using polysulfone ultrafiltration membranes, absorbing polymers and polypiperazine amide reverse osmosis membranes. The process was optimized so that from wastewater entering with a COD content of about 90,000 ppm it was possible to obtain a COD reduction of about 99% with the recovery of polyphenols to use in alimentary industries and of a “concentrated paste” for oil extraction, phurphurale production or combustion. Also evaluated was the economical feasibility of industrial application calculating that the total cost of the treatment was close to 3 c per liter. 相似文献
52.
Molini U Traversa D Ceschia G Iorio R Boffo L Zentilin A Capelli G Giangaspero A 《Journal of food protection》2007,70(2):494-499
In order to evaluate the temporal occurrence of Cryptosporidium oocysts in Ruditapes philippinarum clams bred along the northeastern Italian Adriatic coast and molecularly characterize the isolates, 2,160 specimens (180 clams per month) were collected from three clam farms from January to December 2004. Two farms (sites A and B) were located in Venice (Chioggia, Veneto region) and one (site C) in the Marano Lagoons (Friuli Venezia Giulia region). Clams from 36 pools (i.e., one pool of 60 clams per month per site) were subjected to a high-sensitivity seminested PCR assay specific for a 360-bp diagnostic region internal to the Cryptosporidium spp. outer wall protein gene. Positive amplicons were sequenced and analyzed. Cryptosporidium DNA was found in clams from seven pools (sites A and B) during 1 month of sampling at site A and 6 months of sampling at site B, with Cryptosporidium hominis and Cryptosporidium parvum being detected. The expected infection rate of the clams was 0.36%. Site B showed a significantly higher expected infection rate (1.15%) than did the other sites (A = 0.14% and C = 0%). Given its high sensitivity and specificity, this seminested PCR assay can be considered a reliable tool for detecting and distinguishing species within the Cryptosporidium genus. The seasonal pattern of contamination and the related public health risks are of particular concern. 相似文献
53.
Tchernycheva M Cirlin GE Patriarche G Travers L Zwiller V Perinetti U Harmand JC 《Nano letters》2007,7(6):1500-1504
We report on the fabrication by Au-assisted molecular beam epitaxy of InP nanowires with embedded InAsP insertions. The growth temperature affects the nucleation on the nanowire lateral surface. It is therefore possible to grow the wires in two steps: to fabricate an axial heterostructure (at 420 degrees C), and then cover it by a shell (at 390 degrees C). The InAsP alloy composition could be varied between InAs0.35P0.65 and InAs0.5P0.5 by changing the As to P flux ratio. When a shell is present, the InAsP segments show strong room-temperature photoluminescence with a peak wavelength tunable from 1.2 to 1.55 mum by adjusting the As content. If the axial heterostructure has no shell, luminescence intensity is drastically reduced. Low-temperature microphotoluminescence performed on isolated single wires shows narrow peaks with a line width as small as 120 microeV. 相似文献
54.
Chiara Di Berardino Alessia Peserico Giulia Capacchietti Martina Crociati Maurizio Monaci Umberto Tosi Annunziata Mauro Valentina Russo Nicola Bernab Barbara Barboni 《International journal of molecular sciences》2021,22(22)
The use of assisted reproductive technologies (ART) still requires strategies through which to maximize individual fertility chances. In vitro folliculogenesis (ivF) may represent a valid option to convey the large source of immature oocytes in ART. Several efforts have been made to set up ivF cultural protocols in medium-sized mammals, starting with the identification of the most suitable gonadotropic stimulus. In this study, Equine Chorionic Gonadotropin (eCG) is proposed as an alternative to Follicle Stimulating Hormone (FSH) based on its long superovulation use, trans-species validation, long half-life, and low costs. The use of 3D ivF on single-ovine preantral (PA) follicles allowed us to compare the hormonal effects and to validate their influence under two different cultural conditions. The use of eCG helped to stimulate the in vitro growth of ovine PA follicles by maximizing its influence under FBS-free medium. Higher performance of follicular growth, antrum formation, steroidogenic activity and gap junction marker expression were recorded. In addition, eCG, promoted a positive effect on the germinal compartment, leading to a higher incidence of meiotic competent oocytes. These findings should help to widen the use of eCG to ivF as a valid and largely available hormonal support enabling a synchronized in vitro follicle and oocyte development. 相似文献
55.
Chiara Maddaloni Domenico Umberto De Rose Alessandra Santisi Ludovica Martini Stefano Caoci Iliana Bersani Maria Paola Ronchetti Cinzia Auriti 《International journal of molecular sciences》2021,22(22)
Sepsis causes high rates of morbidity and mortality in NICUs. The estimated incidence varies between 5 and 170 per 1000 births, depending on the social context. In very low birth-weight neonates, the level of mortality increases with the duration of hospitalization, reaching 36% among infants aged 8–14 days and 52% among infants aged 15–28 days. Early diagnosis is the only tool to improve the poor prognosis of neonatal sepsis. Blood culture, the gold standard for diagnosis, is time-consuming and poorly sensitive. C-reactive protein and procalcitonin, currently used as sepsis biomarkers, are influenced by several maternal and fetal pro-inflammatory conditions in the perinatal age. Presepsin is the N-terminal fragment of soluble CD14 subtype (sCD14-ST): it is released in the bloodstream by monocytes and macrophages, in response to bacterial invasion. Presepsin seems to be a new, promising biomarker for the early diagnosis of sepsis in neonates as it is not modified by perinatal confounding inflammatory factors. The aim of the present review is to collect current knowledge about the role of presepsin in critically ill neonates. 相似文献
56.
Rogerio Berardi Thomas T. Scherb 《国际造纸》2009,28(4):7-9
福伊特造纸的ATMOS技术是卫生纸生产技术的一大突破,它解决了同一台纸机生产不同等级卫生纸的问题,在市场上具有广阔的应用前景。 相似文献
57.
Guido Busca Umberto Costantino Tania Montanari Gianguido Ramis Carlo Resini Michele Sisani 《International Journal of Hydrogen Energy》2010
The urea hydrolysis method allowed to prepare well-crystallized Ni–Co–Zn–Al Layered Double Hydroxides to be used as precursors of mixed oxide catalysts for the Ethanol Steam Reforming (ESR) reaction. The calcination of the layered precursors gives rise to high surface area mixed oxides, being actually a mixture of a rock salt phase (NiO), a wurtzite phase (ZnO) and a spinel phase. 相似文献
58.
Giacomo Pepe Andrea Cevasco Laura Gaggero Riccardo Berardi 《Bulletin of Engineering Geology and the Environment》2017,76(2):629-644
Intact rock strength and stiffness properties are commonly used in rock mass mechanical characterization, and their evaluation is usually based on laboratory tests. Due to the variability that affects strength and stiffness parameters, the determination of the number of laboratory-tested specimens required to obtain a reliable reference value is very useful. However, many studies reported in apposite literature focused only on the variability of strength parameters. This study investigates the variability of some of the most important strength and stiffness properties (unconfined compressive strength, indirect tensile strength, tangent and secant Young’s moduli, Poisson’s ratio) by applying statistical methods (statistical decision theory and statistical inference theory). A data set of 451 laboratory tests was used, performed on three rock types. The statistical analyses were applied with the aim of assessing how closely intact rock laboratory data follow a normal distribution and determining the minimum number of specimens required to obtain a reliable average value of the parameters in relation to a targeted precision index for a confidence level of 95 %. The results indicate that the minimum number of samples needed varies depending on rock and test types. Among the stiffness properties, tangent Young’s modulus has a lower variability than both the secant modulus and the Poisson’s ratio, whereas in terms of strength parameters, unconfined compressive strength is subject to greater variability than indirect tensile strength. 相似文献
59.
Claudio Chiastra Stefano Morlacchi Diego Gallo Umberto Morbiducci Rubén Cárdenes Ignacio Larrabide Francesco Migliavacca 《Journal of the Royal Society Interface》2013,10(84)
One of the relevant phenomenon associated with in-stent restenosis in coronary arteries is an altered haemodynamics in the stented region. Computational fluid dynamics (CFD) offers the possibility to investigate the haemodynamics at a level of detail not always accessible within experimental techniques. CFD can quantify and correlate the local haemodynamics structures which might lead to in-stent restenosis. The aim of this work is to study the fluid dynamics of realistic stented coronary artery models which replicate the complete clinical procedure of stent implantation. Two cases of pathologic left anterior descending coronary arteries with their bifurcations are reconstructed from computed tomography angiography and conventional coronary angiography images. Results of wall shear stress and relative residence time show that the wall regions more prone to the risk of restenosis are located next to stent struts, to the bifurcations and to the stent overlapping zone for both investigated cases. Considering a bulk flow analysis, helical flow structures are generated by the curvature of the zone upstream from the stent and by the bifurcation regions. Helical recirculating microstructures are also visible downstream from the stent struts. This study demonstrates the feasibility to virtually investigate the haemodynamics of patient-specific coronary bifurcation geometries. 相似文献
60.
Characterization of Swiss vineyards using isotopic data in combination with trace elements and classical parameters 总被引:2,自引:0,他引:2
Gérard?GremaudEmail author Sylvie?Quaile Umberto?Piantini Elmar?Pfammatter Claude?Corvi 《European Food Research and Technology》2004,219(1):97-104
The objective of this work was to study methods to check the geographical origin of Swiss wines. Authentic grape samples from the vintages 2000 and 2001 were collected in representative locations, and the wines produced from these samples were subjected to isotopic (2H/1Hethanol; 18O/16Owine water), elemental (Mn, Al, B, Ba, Ca, Fe, Mg, Na, Rb, Sr, Zn) and FT-IR (ethanol, pH, total acidity, volatile acidity, malic acid, fructose, tartaric acid, lactic acid, succinate, citric acid, glycerol, 2,3-butandiol, dry matter and relative density (d20)) analyses. The results showed that the variables 18O/16Owine water, strontium, rubidium, and ethanol%, when considered in a monovariate approach, allowed the best discrimination of the geographical origins of Swiss wines. By using a combination of all variables (multivariate approach), Switzerland was divided in four main production zones with a separation power that has never before been achieved. These zones were defined as Tessin, Valais, Romandie and Alemanique. A fifth zone (Graubünden) could be evidenced in vintage 2001. 相似文献