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941.
Leggio A Belsito EL De Marco R Di Gioia ML Liguori A Siciliano C Spinella M 《Journal of food science》2012,77(4):S170-S175
This paper compares some important parameters and the free amino acid and biogenic amine contents of cured industrial and homemade meat products. To this aim, industrial and homemade "soppressata" and "salsiccia", typical dry fermented sausages produced in Southern Italy, were analyzed. The homemade sausages showed a higher level of free biogenic amines than that manufactured industrially, most likely because biogenic amine formation in industrial products is limited by the use of starter cultures. The industrial sausages are characterized by a higher total free amino acid content than the homemade products. Overall, free amino acid and biogenic amine contents demonstrated that appreciable differences exist between homemade and industrial sausages. 相似文献
942.
Carlo Galiotto Nicola Marchetti Neeli Prasad Ramjee Prasad 《Wireless Personal Communications》2012,64(1):169-183
Even though radio frequency identification (RFID) systems are spreading more and more as a medium for identification, location
and tracking purposes, some reliability issues of these systems still need to be solved. In fact, RFID readers and tags experience
collisions when sharing the wireless transmission channel over the same area. In this work, we propose a centralized scheduling-based
algorithm as possible candidate solution for the reader collision problem in passive RFID systems. This algorithm has been
designed taking into account the circuitry limitations of the tags, which do not allow the usage of frequency or code division
multiple access schemes in passive RFID systems. The solution herewith proposed, which is suitable for those scenarios involving
static or low mobility readers, aims at preventing reader collisions and provides at the same time low channel access delay
to the readers. The performance of this algorithm has been tested via computer simulations. The results show that the proposed
solution strongly reduces collision occurrences and, especially in static scenarios, provides low access delay to the readers
during the channel contention phase. 相似文献
943.
Carlo Ignazio Giovanni Tuberoso Mladen Boban Ersilia Bifulco Danijela Budimir Filippo Maria Pirisi 《Food chemistry》2013
The aim of this work was to use different assays to evaluate the antioxidant and vasodilatory properties of three typical food products from the Mediterranean area and to correlate these activities with their phenolic content. For this purpose, red wines Cannonau, liqueurs obtained by cold maceration of myrtle (Myrtus communis L.) berries and bitter honeys obtained from strawberry-tree flowers (Arbutus unedo L.) were analysed. The total phenolic (TP) content was measured spectrophotometrically with a modified Folin–Ciocalteau method and phenolic compounds were identified and dosed by HPLC-DAD and LC-MS/MS. Antioxidant activities were evaluated with DPPH, FRAP and ABTS assays and the in vitro vasodilatory effects were assessed using norepinephrine precontracted rat aortic rings. Cannonau wines and myrtle liqueurs showed high levels of TP (1978 ± 279 and 1741 ± 150 mg GAE/L, respectively), linearly correlated to the results of FRAP, ABTS, and DPPH assays. Their maximal vasodilatory activity was 61.7 ± 4.1% and 53.0 ± 3.0%, respectively. Although strawberry-tree honey contained relatively high levels of phenolic compounds (922 ± 38 mg GAE/kg), it did not induce vasodilation, even at the highest dose tested (0.206 g/L). These results indicate that foods with high levels of phenolic compounds should be studied using several different biological assays before being recommended to the general public as functional foods. 相似文献
944.
945.
Castigliego L Li XN Armani A Grifoni G Boselli C Rosati R Gianfaldoni D Guidi A 《The Journal of dairy research》2011,78(4):412-420
Recombinant bovine somatotropin (rbST) is used to increase milk yield in cows, but it has been forbidden in some countries and in the EU. However, rbST misuse represents a concern in both bovine and buffalo dairy production. A number of studies on rbST treatment have been performed on bovines, but there are few data on buffaloes. In this study, we treated eight lactating buffaloes with biweekly injections of a slow-release formulation of rbST, for five cycles of administration, and analysed total ST and insulin-like growth factor 1 (IGF-1) variations in serum and IGF-1 in milk. The aim was to assess their power as potential indicators of rbST-treatment. Blood was collected on days 2, 5, 9 and 14 of each cycle, and milk on days 2, 9 and 14 of cycles 2 and 5. Results showed an extraordinary increase in ST levels on day 2 in treated animals, followed by a rapid decrease over the following days, while a significant increase in IGF-1 was observed both in serum and in milk throughout most of each cycle. These results suggest that serum ST levels are a good indicator of treatment. However, the rapid decrease after the peak limits the useful period of sample collection. 相似文献
946.
Purbasha Nandi Shan Li Rod Carlo A. Columbres Feng Wang Dewight R. Williams Yu-Ping Poh Tsui-Fen Chou Po-Lin Chiu 《International journal of molecular sciences》2021,22(15)
IBMPFD/ALS is a genetic disorder caused by a single amino acid mutation on the p97 ATPase, promoting ATPase activity and cofactor dysregulation. The disease mechanism underlying p97 ATPase malfunction remains unclear. To understand how the mutation alters the ATPase regulation, we assembled a full-length p97R155H with its p47 cofactor and first visualized their structures using single-particle cryo-EM. More than one-third of the population was the dodecameric form. Nucleotide presence dissociates the dodecamer into two hexamers for its highly elevated function. The N-domains of the p97R155H mutant all show up configurations in ADP- or ATPγS-bound states. Our functional and structural analyses showed that the p47 binding is likely to impact the p97R155H ATPase activities via changing the conformations of arginine fingers. These functional and structural analyses underline the ATPase dysregulation with the miscommunication between the functional modules of the p97R155H. 相似文献
947.
Junctions based on mesoscopic Hg electrodes are used to characterize the electrical properties of the organic molecules organized in self-assembled monolayers (SAMs). The junctions M-SAM//SAM-Hg are formed by one electrode based on metals (M) such as Hg, Ag, Au, covered by a SAM, and by a second electrode always formed by a Hg drop carrying also a SAM. The electrodes, brought together by using a micromanipulator, sandwich SAMs of different nature at the contact area (approximately = 0.7 microm2). The high versatility of the system allows a series of both electrical and electrochemical junctions to be assembled and characterized: (i) The compliant nature of the Hg electrodes allows incorporation into the junction and measurement of the electrical behavior of a large number of molecular systems and correlation of their electronic structure to the electrical behavior; (ii) by functionalizing both electrodes with SAMs exposing different functional groups, X and Y, it is possible to compare the rate of electron transfer through different X...Y molecular interactions; (iii) when the junction incorporates one of the electrode formed by a semitransparent film of Au, it allows electrical measurements under irradiation of the sandwiched SAMs. In this case the junction behaves as a photoswitch; iv) incorporation of redox centres with low lying, easily reachable energy levels, provides electron stations as indicated by the hopping mechanism dominating the current flow; (v) electrochemical junctions incorporating redox centres by both covalent and electrostatic interactions permit control of the potential of the electrodes with respect to that of the redox state by means of an external reference electrode. Both these junctions show an electrical behavior similar to that of conventional diodes, even though the mechanism generating the current flow is different. These systems, demonstrating high mechanical stability and reproducibility, easy assembly, and a wide variety of produced results, are convenient test-beds for molecular electronics and represent a useful complement to physics-based experimental methods. 相似文献
948.
Carlo Cattani 《Telecommunication Systems》2010,43(3-4):207-217
The analysis of a periodic signal with localized random (or high frequency) noise is given by using harmonic wavelets. Since they are orthogonal to the Fourier basis, by defining a projection wavelet operator the signal is automatically decomposed into the localized pulse and the periodic function. An application to the analysis of a self-similar non-stationary noise is also given. 相似文献
949.
Mariana Navarro Benevides David Bruno de Sousa Teixeira Joyce Correna Carlo 《建筑学研究前沿(英文版)》2022,11(1):161-177
This study aimed to propose climatic zones in the Brazilian semiarid region using multivariate statistical techniques and to characterize these zones for energy efficiency applications in buildings. Principal component analysis (PCA) was used to select the variables with the greatest practical relevance. From this selection, hierarchical cluster analysis (HCA) was used to spatially define climatically homogeneous zones. For each defined zone, the most feasible constructive thermal conditioning strategies were defined, and the thermal indexes of heat and degree-hours of cooling and heating were calculated. As result, PCA reduced the dimensionality of the initial database from 104 to 48 variables, among which the climatic and bioclimatic variables related to temperature stood out. From the HCA, three climatic zones were defined for the Brazilian semiarid region. For all zones, there was a high demand for constructive conditioning strategies, which have to be adopted in more than half of the total annual hours. The proposed zoning is adapted to the climatic aspects of the Brazilian semiarid and has significant potential for applications in construction planning in this region. Moreover, the methodology presented can be applied for establishing climatic zones in other regions, which can contribute to increasing the energy efficiency of buildings. 相似文献
950.
R Aversano MR Ercolano I Caruso C Fasano D Rosellini D Carputo 《International journal of molecular sciences》2012,13(8):10316-10335
Polyploidy is a very common phenomenon in the plant kingdom, where even diploid species are often described as paleopolyploids. The polyploid condition may bring about several advantages compared to the diploid state. Polyploids often show phenotypes that are not present in their diploid progenitors or exceed the range of the contributing species. Some of these traits may play a role in heterosis or could favor adaptation to new ecological niches. Advances in genomics and sequencing technology may create unprecedented opportunities for discovering and monitoring the molecular effects of polyploidization. Through this review, we provide an overview of technologies and strategies that may allow an in-depth analysis of polyploid genomes. After introducing some basic aspects on the origin and genetics of polyploids, we highlight the main tools available for genome and gene expression analysis and summarize major findings. In the last part of this review, the implications of next generation sequencing are briefly discussed. The accumulation of knowledge on polyploid formation, maintenance, and divergence at whole-genome and subgenome levels will not only help plant biologists to understand how plants have evolved and diversified, but also assist plant breeders in designing new strategies for crop improvement. 相似文献