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51.
This work deals with the prediction of the geographical origin of monovarietal virgin olive oil (cv. Koroneiki) samples from three regions of southern Greece, namely, Peloponnesus, Crete, and Zakynthos, and collected in five harvesting years (2001-2006). All samples were chemically analyzed by means of 1H and 31P NMR spectroscopy and characterized according to their content in fatty acids, phenolics, diacylglycerols, total free sterols, free acidity, and iodine number. Biostatistical analysis showed that the fruiting pattern of the olive tree complicates the geographical separation of oil samples and the selection of significant chemical compounds. In this way the inclusion of the harvesting year improved the classification of samples, but increased the dimensionality of the data. Discriminant analysis showed that the geographical prediction at the level of three regions is very high (87%) and becomes (74%) when we pass to the thinner level of six sites (Chania, Sitia, and Heraklion in Crete; Lakonia and Messinia in Peloponnesus; Zakynthos). The use of classification and binary trees made possible the construction of a geographical prediction algorithm for unknown samples in a self-improvement fashion, which can be readily extended to other varieties and areas.  相似文献   
52.
This report aims to describe the first case of muscular and collagenous choristoma in a dog. A 10-yr-old female mixed-breed dog presented with lateral recumbence, vocalization, positional vertical nystagmus, divergent strabismus, anisocoria, and status epilepticus. The clinical condition evolved to stupor and ultimately, death. Necropsy revealed a white mass causing an irregular increase in the volume of the cerebellar vermis. In histological analysis, a well circumscribed, unencapsulated mass was observed in the cerebellum, consisting of fibers of striated skeletal muscle and collagen fibers, mostly mineralized. Based on the histopathological and histochemical findings, a diagnosis of muscular and collagenous cerebellar choristoma was made.  相似文献   
53.
Based on recent mining rates and the exhaustion of global phosphorus(P)reserves,there is a need to mobilize P already stored in soils,and its recovery from secondary resources such as Ca-and Fe-phosphates is important.The Ca-phosphate hydroxyapatite forms a good fertilizer source,while vivianite is formed in waterlogged soils and sediments.During sludge treatment,the formation of vivianite has been identified,being mainly Fe-phosphate.Long-term P release from both hydroxyapatite and vivianite was studied using different inorganic(CaCl2 and CaSO4)and organic(citric and humic acid)reagents during batch experiments.Reagents CaCl2 and CaSO4 represent the soil solution,while citric and humic acids as organic constituents affect P availability in the rhizosphere and during the process of humification.Additionally,the flow-through reactor(FTR)technique with an infinite sink was used to study the long-term P release kinetics.The cumulative P release was higher by organic acids than by inorganic compounds.The cumulative P release rates were higher in the FTR with CaCl2 as compared to the batch technique.The infinite sink application caused a continuously high concentration gradient between the solid and liquid phases,leading to higher desorption rates as compared to the batch technique.The predominant amount of the total P released over time was available for a short term.While inorganic anion exchange occurred at easily available binding sites,organic acids affected the more heavily available binding sites,which could be embedded within the mineral structure.The results showed that organic compounds,especially citric acid,play a superior role as compared to the inorganic constituents of the soil solution during the recovery of already stored P from the tertiary phosphates vivianite and hydroxyapatite.  相似文献   
54.
Purpose

The effects of long-standing industrialization processes and poor environmental management practices have often left a harmful legacy for marine-coastal sites worldwide, causing a wide range of unforeseen impacts on the ecosystem and on human health. A critical revision of available data from three highly contaminated Italian sites (Augusta Bay, Sicily; Cagliari Gulf, Sardinia; Pozzuoli Bay, Campania) revealed the crucial role of biogeochemical/physical dynamics and potential widespread delivery of contaminants as key components for a wider comprehensive sediment management.

Materials and methods

Datasets of organic pollutants (ΣPAHs, ΣPCBs), heavy metals (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, V, and Zn), radionuclides, and grain size composition of marine sediments of all three sites were critically reviewed and seafloor bathymetric data were analyzed.

Results and discussion

A critical review of available physical and chemical information of sediments collected from the three marine sites provides a better understanding of the physical and biogeochemical dynamics of large-scale dispersion of contaminants in those areas, as well as new insights in terms of improved sediments management policies with actions of larger scale monitoring of the “buffer zone confining with the national relevance and highly contaminated site to trace inputs and accumulation effects of pollutants deriving from the point-source.

Conclusions

This study demonstrates how the presence of polluted sediments on the coastal areas can have, also after the closure of anthropogenic activities, a potential impact at a large scale. Then to better evaluate the effective impact, we suggest the adoption of a buffer zone contiguous to the national relevance sites (SIN) area. While SINs are optimized to define the state of the art of the near-source pollution, buffer zones may help to outline the rate of delivery of pollutants to the deep sea. Buffer zones must be designed by taking into account the local hydrodynamics, sedimentology, and geomorphology, and should be monitored, even if at a lower resolution, like SINs.

  相似文献   
55.
56.
The study investigated the effect of the following maize:legume (70:30) mixed crop silages: maize:cowpea, maize:velvet bean, and maize:lablab on milk production during the 2016 dry season. Using a 5?×?5 double Latin square design, five Holstein-Friesian crossbred cows in early lactation (30?±?15 days) and five Jersey crossbred cows in early lactation (25?±?10 days) were given the supplementary mixed crop silage diets at 0.5 kg/l of milk produced over 105 days. Commercial dairy meal and sole maize silage were used as positive and negative controls, respectively. Milk yield was significantly higher (P?< 0.05) in cows given the dairy meal compared to mixed crop silages; however, milk yield was also significantly higher (P?< 0.05) for cows given the three mixed crop silages compared to cows given sole maize silage. Cows given mixed crop silages produced milk of significantly higher protein content (P?< 0.05) than those given sole maize silage. There was no significant difference (P?> 0.05) in butterfat content of milk across all the dietary treatments. The dietary cost of producing 1 l of milk was highest at 0.31USD/l for cows given commercial dairy meal and lowest for cows given maize:velvet bean and maize:cowpea silage at 0.19USD/kg. The highest dietary gross margins of 68% were observed when cows were given maize:velvet mixed silage compared to commercial dairy meal (47%) and sole maize silage (57%). The 70:30 maize:legume mixed crop silages showed the capability to increase milk quantity and quality at very low production costs in smallholder dairy schemes.  相似文献   
57.
  1. Milanino is a heavy Italian chicken breed included in a conservation project of the University of Milan and is an important genetic resource for alternative production systems. This research was aimed to study the effect of the dietary protein concentration on growth, slaughter performance and meat composition in free-range reared Milanino chickens.

  2. A total of 120 Milanino chickens were fed on different protein concentrations (HP = 20% CP and LP = 16% CP), reared according to a free-range system and slaughtered at 150 and 180 d of age. Growth, slaughter performance and meat (breast and thigh) composition were recorded.

  3. The protein concentration of the diet did not affect the overall Milanino mean body weight recorded in the straight-run group in the whole rearing period. However, the growth rate within sex was significantly different between the dietary treatments: heavier females were found in the HP group from 125 d onwards, while no differences were recorded in male body weights. The protein concentration of the diet did not affect carcass weight data or meat composition.

  4. The present results suggest the use of a low-protein diet for rearing straight-run Milanino chickens for long rearing periods. However, in females, a high-protein diet is recommended from 125 d of age onwards.

  相似文献   
58.
The effect on several anti-nutritional factors in cowpeas (Vigna unguiculata L. Walp) was investigated following treatment at 100°C or 121°C with solutions (0.1% w/v) of kanwa rock salt or NaHCO3 in distilled water. The concentration of polyphenols, calculated as tannic acid, was reduced substantially up to 67% under the alkaline conditions employed, but the reduction appeared to be greater (69–79%) at higher temperature. The loss of phytic acid was greater (27–40%) when beans were cooked in NaHCO3 than in kanwa (11–29%). The concentration of reducing sugars was decreased in all treatment groups especially under alkaline conditions. There was no evidence for the formation of lysinoalanine in any of the samples.  相似文献   
59.
The effects of dietary alpha-tocopheryl acetate (alpha-TA) doses (75, 150, and 225 mg/kg) and the duration of this supplementation (0, 10, 21, 32, and 43 days prior to slaughter) on fatty acid composition, alpha-tocopherol content, and oxidative status were studied either in raw or in cooked dark chicken meat with its skin. With regard to fatty acid composition, raw meat was affected by both dietary factors. Various polyunsaturated fatty acids decreased as a result of higher alpha-TA doses, whereas these fatty acids increased with longer supplementation periods. Cooked meat showed similar trends for the duration of alpha-TA supplementation. On the other hand, alpha-tocopherol content in raw and cooked meat increased as a result of the dose and duration of alpha-TA supplementation. Formation of lipid hydroperoxides and thiobarbituric acid values of these meats were also influenced by these two dietary factors, and the dietary combination of 150 mg/kg of alpha-TA during the last 32 days was optimal in terms of supplementation costs and meat oxidative stability.  相似文献   
60.
Examination of the crocin bleaching assay performance and in-house validation were focused on probe and test compound characteristics, conditions for peroxyl radical generation, reaction monitoring, and expression of results. HPLC and spectrometric examination showed that any authentic commercial saffron (origin, grade) can be used for probe preparation given that (a) interferences, such as tocopherols, are removed, (b) working solution concentration is adequately adjusted, and (c) stock probe solution changes during storage are not neglected. As suggested by log P values, calculated for a great number of radical scavengers (AHs), any AH more polar than Trolox (common reference compound) can be tested in the aqueous environment of the assay. AH activities order obeyed principles of structure-activity relationships. The assay was robust toward preheating of the azo-initiator (2,2'-azobis(2-aminopropane) dihydrochloride). Reaction monitoring through periodic UV-vis spectra recording was very informative. An alternative expression of results as "percent inhibition of crocin bleaching value", % Inh = [(DeltaA(0) - DeltaA)/DeltaA(0))] x 100, is proposed for [AH]/[crocin] = 1, instead of the so far used k(rel) values. The above findings also lead to analysis cost and time reduction.  相似文献   
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