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51.
52.
The aim of the present work was to study distribution and reciprocal relationships of fat depots in heavy pigs of several genetic types. On 161 barrows and gilts belonging to four genetic types (Large White and relative crosses with Italian Landrace, Belgian Landrace and Duroc), slaughtered from 125 to 180 kg l.w., thickness, colour (C.I.E, L*, a*, b*) and weight of backfat and of kidney fat were determined. Subcutaneous and intermuscular fat of ham were weighed. On biceps femoris, semimembranosus and semitendinosus muscles ether extract content was determined. Allometric analysis showed that body growth did not particularly increase the intramuscular fat content of the ham. Principal component analysis indicated that PC1 (0.43% of variation) represented the overall fatness, associated all the depots in a similar manner, and was linked to body weight and sex. PC2 (0.22% of variation), linked to genotypes and body weight, expressed the opposition between intramuscular fat deposition and subcutaneous and internal fat accumulation. Using measurements easily recorded on the side (backfat thickness and colour, percent kidney fat), only the estimate of subcutaneous fat, among ham depots, showed good accuracy (R(2)=0.65).  相似文献   
53.
A full-scale unreinforced masonry (URM) wall with an opening was tested under in-plane lateral loading. The wall was first subjected to monotonically increasing displacements until a moderate damage level was reached. The damaged specimen was then cyclically tested up to almost the same maximum drift attained during the monotonic test to investigate the effects of previous damage on its nonlinear response. Finally, the masonry wall was repaired with inorganic matrix-grid (IMG) composites and subjected to a cyclic displacement-controlled test up to a near-collapse state. Most of the observed damage developed in the spandrel panel affecting both lateral resistance and strength degradation. Rocking of piers governed lateral stiffness and hysteretic response, which was characterized by low residual displacements and recentering behavior. The comparison between the experimental force-displacement curves demonstrated that the IMG strengthening system was able to provide energy dissipation capacity to the spandrel panel, restoring load-bearing capacity of the as-built wall, and delaying strength degradation that was indeed observed at larger displacements. Bilinear idealizations of force-displacement curves allowed the identification of displacement ductility, global overstrength, and strength reduction factor of the tested wall systems.  相似文献   
54.
Past experimental tests on a full-scale masonry wall with an opening evidenced the key role of the spandrel panel in the in-plane nonlinear response of the system. Recent seismic codes do not provide specific criteria to assess and to strengthen existing masonry spandrel panels with inorganic matrix-grid (IMG) composites. Numerical finite-element (FE) analyses are used to deepen the knowledge about the nonlinear response of masonry walls and the role of the IMG strengthening system. The comparison of experimental and numerical results contributes to the development of a simplified analytical model to assess the influence of the external reinforcement system on the in-plane seismic response of masonry wall systems. Some hints about the strengthening design that could change the failure mode from brittle shear to ductile flexure are given. Finally, a further enhancement of the IMG strengthening system is proposed to avoid the undesirable splitting phenomena attributable to compression forces and to exploit the full compressive strength of masonry against bending moments.  相似文献   
55.
Helicobacter pylori (Hp) is an organism commonly present worldwide in the human population, sometimes causing serious illnesses such as duodenal and gastric ulcers, adenocarcinoma of the stomach, and low-grade B-cell mucosa-associated lymphoid tissue lymphoma of the stomach. This article describes a multiplex-touchdown PCR method for the identification and genotyping (vacA-s1/m1, sl/m2, and s2/m2-and cagA genes) of Hp directly from sheep milk artificially contaminated with Hp strains from human gastric biopsies and with Hp ATCC 43504. The strains from humans carried sl/m2 cagA+ and s2/m2 cagA allelic combinations, while the ATCC strains carried an sl/ml cagA+ allelic combination. The technique showed a sensitivity of 15 CFU/ml for species identification and of 1,500 CFU/ml for the detection of genes encoding for VacA and CagA. It has proven to be specific and rapid, and the authors suggest that it be used as a rapid screening method to ensure that sheep milk is uncontaminated with this organism.  相似文献   
56.
57.
We report the detection of Listeria spp. and Listeria monocytogenes in 34 dairy plants. In total, 547 of food, product contact surface and floor drain samples were collected along the product lines. Nineteen cheese factories (55.8%) were contaminated by Listeria spp. Of these 20.6% were L. monocytogenes positive. Listeria spp. was found in 6.8% of food samples, 11.3% of product contact surfaces and 40.6% of floor drains. L. monocytogenes was found in 2.4% of food samples, 4.9% of product contact surfaces and 18.8% of floor drains. Twentyfive L. monocytogenes isolates were serotyped using commercial specific antisera and genotyped using Amplified Fragment Length Polymorphism (AFLP) analysis. AFLP genotyping discriminated the four species of Listeria isolated and different genotypes for each species, moreover it could identify persistent genotypes in some dairy facilities. Listeria spp. and L. monocytogenes are widely spread in the dairy sector and probably contaminate foods during the production process. Facility-based monitoring can identify possible routes of transmission and thus allow establishment of more effective strategies to prevent food contamination.  相似文献   
58.
Existing algorithms for wideband direction finding are mainly based on local approximations of the Gaussian log-likelihood around the true directions of arrival (DOAs), assuming negligible array calibration errors. Suboptimal and costly algorithms, such as classical or sequential beamforming, are required to initialize a local search that eventually furnishes DOA estimates. This multistage process may be nonrobust in the presence of even small errors in prior guesses about angles and number of sources generated by inherent limitations of the preprocessing and may lead to catastrophic errors in practical applications. A new approach to wideband direction finding is introduced and described. The proposed strategy combines a robust near-optimal data-adaptive statistic, called the weighted average of signal subspaces (WAVES), with an enhanced design of focusing matrices to ensure a statistically robust preprocessing of wideband data. The overall sensitivity of WAVES to various error sources, such as imperfect array focusing, is also reduced with respect to traditional CSSM algorithms, as demonstrated by extensive Monte Carlo simulations  相似文献   
59.
The enteric nervous system plays a role on the stimulation of secretory cells of intestinal epithelia. We have demonstrated that ablation of ENS stimulates epithelial cell proliferation. As goblet cells are important constituents of the epithelial sheet, it is mandatory to investigate separately this cell type. The myenteric plexus of the ileum of rats in postnatal development was partially removed by the serosal application of benzalkonium chloride (BAC). Three groups of animals were used: those where BAC application was at 13 days and sacrifice was at 15 (13/28-day-old) or 23 days after treatment (13/36-day-old), and those where BAC was applied at 21 days and rats were killed 15 days after treatment (21/36-day-old) . The number of goblet cells in the ileum was estimated in sections stained by periodic acid-Schiff (PAS) histochemistry. In the 13/28 and 21/36 groups, the number of goblet cells was significantly higher after BAC treatment. These results suggest that the myenteric denervation may have an acute effect on the number of goblet cell in suckling and weanling rats, probably through submucous plexus.  相似文献   
60.
This paper aims to define the stability over the time of chemical elemental patterns in some citrus varieties of PGI (Protected Geographical Indication) and not PGI Interdonato and Lunario cultivars coming from Italy and Turkey and to set up a range of markers useful to trace their geographical origin. During the 2015–2017 growing seasons, all fruits were collected and subjected to Inductively Coupled Mass spectrometry (ICP-MS) analysis, in order to determine the multielemental chemical profiles. The chemical variability was calculated for each element by Multi-way analysis of variance. The results highlighted how the measured Cr, Ni, Al, K, Fe and Zn levels mainly depend on the soil composition and the fingerprint allow to trace the geographical origins. Moreover, the stepwise linear discriminant analysis (SLDA) has allowed to correctly classify the 100% of lemon pulps provenances, based on Ni, Al, K, Ca and Na contents. Finally, our study demonstrates the role played by harvest years, variety and soils composition whose interaction contributed to define the chemical fingerprints.  相似文献   
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