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71.
Angelucci G Meloni M Merella P Sardu F Madeddu S Marrosu R Petza F Salati F 《Journal of food protection》2011,74(10):1769-1775
A study was carried out on the presence of Anisakis and Hysterothylacium larvae in fish and cephalopods caught in Sardinian waters. A total of 369 specimens of 24 different species of teleosts and 5 species of cephalopods were collected from different fishing areas of Sardinia. Larvae were detected and isolated by both visual inspection and enzymatic digestion. These methods allowed Anisakis type I and type II third-stage larvae and Hysterothylacium third- and fourth-stage larvae to be detected. The prevalence, mean intensity, and mean abundance were calculated. The results obtained showed the highest prevalence of Anisakidae in Zeus faber (100%) and of Anisakis in Micromesistius poutassou (87.5%). The highest prevalence of Anisakis type I larvae was in M. poutassou (81.2%), and that of Anisakis type II larvae was in Todarodes sagittatus (20%). The highest values for prevalence, mean intensity, and mean abundance for Hysterothylacium were found in Z. faber. These prevalences and the mean intensity and abundance were higher than those reported by different authors in other Mediterranean areas. This may be because the enzymatic digestive method used in this research resulted in higher recovery levels. The data suggest that Sardinia may be a high-risk area for zoonotic diseases and that measures such as information campaigns, aimed at both sanitary service personnel and consumers, should be employed to limit the spread of such zoonosis. 相似文献
72.
M Uhl KH Allmann C Ihling MP Hauer W Conca M Langer 《Canadian Metallurgical Quarterly》1998,27(12):677-682
In this study the small-intestine phenotype in rat colonic tumors was investigated in terms of sucrase and intestinal-type alkaline phosphatase (I-ALP) activity. F344 rats were given intraperitoneal injections of methylazoxymethanol acetate at a dose level of 25 mg/kg body weight once a week for 8 weeks and were killed 40 weeks after the first injection. Sucrase and I-ALP activities in proximal and distal colon adenocarcinomas were significantly higher than those in the normal colon epithelium. In the jejunum, by contrast, normal tissue had significantly higher levels than tumors. Immunohistochemical staining of I-ALP was also strong in striated cell borders of colon adenocarcinoma cells. These data suggest that, whereas absorptive cells of the small intestine lose their own traits with tumor development, colonocytes acquire phenotypic features of the small intestine. Intestinal enzymes associated with the striated-cell border, such as sucrase and I-ALP, may be useful markers for malignant phenotypic expression in colonocytes. 相似文献
73.
O. Catalano G. Agnetta B. Biondo F. Celi R. Di Raffaele S. Giarrusso J. Linsley G. La Rosa A. Lo Bue A. Mangano F. Russo 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2002,480(2-3):547-554
The balloon-borne experiment, named BAckground BYpass (BABY) belongs to a wider program that has as its final goal the detection and study of high-energy cosmic rays from space (satellite, Space Station). An information of fundamental importance for this class of projects concerns the nighttime background light. The instrument designed to detect fluorescence photons is basically composed of two collimated photomultipliers: a single photon-counting PMT and a charge integration PMT. We briefly report the details of the design, operation and performance of the detector, which was designed and completely built at the IFCAI–CNR Institute in Palermo. Preliminary analysis and results of the nocturnal background in the range of 300–400 nm are presented for the whole duration of the flight during the 1998 Mediterranean balloon flight campaign. A substantial part of the flight was at night over the sea. 相似文献
74.
Gianluca Bianchini Marcello Crucianelli Claudia Crestini Raffaele Saladino 《Topics in Catalysis》2006,40(1-4):221-227
Polymer-supported methyltrioxorhenium (MTO) compounds are shown to act as efficient and selective catalysts for the oxy-functionalization
of C–H bonds in representative hydrocarbon derivatives (leading to the corresponding alcohols or ketones), using H2O2 as oxidant. The different supports used for the heterogenation of MTO, such as poly(4-vinylpyridine), poly(4-vinylpyridine)-N-oxide and polystyrene resins, all showed different catalytic behaviour in terms of substrate conversion and product yield,
depending on the experimental conditions used. It is noteworthy that the novel heterogeneous catalysts were found to be stable,
it being possible to effect their recover and recycle at least five times without appreciable loss of activity. 相似文献
75.
Patruno F Aliverti A Dellacà RL Burns D Pedotti A 《IEEE transactions on bio-medical engineering》2005,52(1):88-96
Scanhead tracking by opto-electronic (OE) systems allows high accuracy in three-dimensional (3-D) freehand ultrasound imaging. In this paper, a new set of methods is proposed and compared with the standard approach [Gram-Schmidt method (GS)]. Three redundancy-based algorithms are introduced to compensate for possible loss of markers during data acquisition: regression plane (RP), multiple Gram-Schmidt (MGS), and center of mass least square (CMLS). When combined with the ultrasound instrument, the root-mean-squared (RMS) uncertainty in locating target points, over a working volume of 420 mm x 490 mm x 100 mm, improved by 7% and 24% using MGS and CMLS method respectively, compared to GS. A lower improvement was obtained with RP methods (5%), using the best marker configuration. In conclusion, CMLS method provides a robust and accurate procedure for 3-D freehand ultrasound scanhead tracking, able to manage possible loss of markers, with interesting perspectives for image fusion and body referenced 3-D ultrasound. 相似文献
76.
Understanding foods as soft materials 总被引:5,自引:0,他引:5
Foods make up some of the most complex examples of soft condensed matter (SCM) with which we interact daily. Their complexity arises from several factors: the intricacy of components, the different aggregation states in which foods are encountered, and the multitude of relevant characteristic time and length scales. Because foodstuffs are governed by the rules of SCM physics but with all the complications related to real systems, the experimental and theoretical approaches of SCM physics have deepened our comprehension of their nature and behaviour, but many questions remain. In this review we discuss the current understanding of food science, by considering established SCM methods as well as emerging techniques and theoretical approaches. With their complexity, heterogeneity and multitude of states, foods provide SCM physics with a challenge of remarkable importance. 相似文献
77.
The recent resurgence of growth studies has clearly established that technological progress and knowledge accumulation are
among the most important factors in determining the performance of regional and national economic systems. In this paper we
propose new evidence on knowledge flows across European regions based on patenting at the European Patent Office. We examine
in- and out-flows of patent citations as a proxy of knowledge connections, while looking also at their dynamics through time.
The econometric analysis is based on a model where the exchange of knowledge across regions is mainly affected by geographical
distance together with a set of spatial variables. The main result is that knowledge flows decrease as the geographical distance
between the origin and the destination region increase. Furthermore, knowledge flows tend to be higher among contiguous regions
and areas within the same country. These results prove to be robust with respect to the inclusion of other characteristics
of the origin and destination regions (production structure, economic conditions and technological efforts) as well as different
estimation methods. 相似文献
78.
This paper proposes a new and low complexity technique for the simultaneous achievement of open and closed loop diagonal dominance for uncertain plants. The method is based on the introduction of a static high gain inner feedback which modifies the plant to attain a diagonal dominant open loop compensated plant. The sufficient, easy to use, conditions derived for the open loop diagonal dominance also assure the simultaneous achievement of closed loop diagonal dominance under soft assumptions on the diagonal elements of the decoupled controller robustly stabilizing the plant. These assumptions agree with the usual closed‐loop performance specifications, so that closed‐loop diagonal dominance is achieved without any extra complication on the controller design procedure. The main merits of the present method are: applicability to uncertain plants, ease of implementation and low computational cost. Three examples taken from the relevant literature, are given to show the effectiveness of the proposed approach. 相似文献
79.
Alessandro Pagano Irene Pluchinotta Raffaele Giordano Anna Bruna Petrangeli Umberto Fratino Michele Vurro 《Water Resources Management》2018,32(6):2131-2145
The availability and the quality of drinking water are key requirements for the well-being and the safety of a community, both in ordinary conditions and in case of disasters. Providing safe drinking water in emergency contributes to limit the intensity and the duration of crises, and is thus one of the main concerns for decision-makers, who operate under significant uncertainty. The present work proposes a Decision Support System for the emergency management of drinking water supply systems, integrating: i) a vulnerability assessment model based on Bayesian Belief Networks with the related uncertainty assessment model; ii) a model for impact, and related uncertainty assessment, based on Bayesian Belief Networks. The results of these models are jointly analyzed, providing decision-makers with a ranking of the priority of intervention. A GIS interface (G-Net) is developed to manage both input spatial information and results. The methodology is implemented in L’Aquila case study, discussing the potentialities associated to the use of the tool dealing with information and data uncertainty. 相似文献
80.
Mohammad Peydayesh Meret Kim Suter Sreenath Bolisetty Samy Boulos Stephan Handschin Laura Nyström Raffaele Mezzenga 《Advanced materials (Deerfield Beach, Fla.)》2020,32(12):1907932
Water contamination by organic pollutants is ubiquitous and hence a global concern due to detrimental effects on the environment and human health. Here, it is demonstrated that amyloid fibrils aerogels are ideal adsorbers for removing organic pollutants from water. To this end, amyloid fibrils prepared from β‑lactoglobulin, the major constituent of milk whey protein, are used as building blocks for the fabrication of the aerogels. The adsorption of Bentazone, Bisphenol A, and Ibuprofen, as model pollutants, is evaluated under quasi-static conditions, without use of energy or pressure. Through adsorption by amyloid fibrils aerogel, excellent removal efficiencies of 92%, 78%, and 98% are demonstrated for Bentazone, Bisphenol A, and Ibuprofen, respectively. Furthermore, the maximum adsorption capacity of amyloid fibrils aerogel for Bentazone, Bisphenol A, and Ibuprofen is 54.2, 50.6, and 69.6 mg g−1, respectively. To shed light on the adsorption equilibrium process, adsorption isotherms, binding constants, saturation limits, and the effect of pH are evaluated. Finally, the regeneration of the aerogel over three consecutive cycles is studied, exhibiting high reusability with no significant changes in its removal performance. These results point at amyloid fibrils aerogels as a sustainable, efficient, and inexpensive technology for alleviating the ubiquitous water contamination by organic pollutants. 相似文献