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41.
Carla C. Eisemberg Mark Rose Benedict Yaru Arthur Georges 《Biological conservation》2011,144(9):2282-2288
Papua New Guinea has astonishing biological and cultural diversity which, coupled with a strong community reliance on the land and its biota for subsistence, add complexity to monitoring and conservation and in particular, the demonstration of declines in wildlife populations. Many species of concern are long-lived which provides additional challenges for conservation. We provide, for the first time, concrete evidence of a substantive decline in populations of the pig-nosed turtle (Carettochelys insculpta); an important source of protein for local communities. Our study combined matched village and market surveys separated by 30 years, trends in nesting female size, and assessment of levels and efficacy of harvest, each of which was an essential ingredient to making a definitive assessment of population trends. Opportunities for an effective response by local communities to these declines needs to consider both conservation and fisheries perspectives because local communities consider the turtle a food resource, whereas the broader global community views it as a high priority for conservation. Our study in the Kikori region is representative of harvest regimes in most rivers within the range of the species in Papua New Guinea, and provides lessons for conservation of many other wildlife species subject to harvest. 相似文献
42.
Raffaele Spinelli Natascia Magagnotti Carla Nati 《European Journal of Forest Research》2011,130(5):737-744
In Italy, poplar plantations represent an important source of wood products, and especially of high-quality veneer logs. These
plantations offer favourable conditions to the introduction of forest mechanisation, and especially easy access and industrial
management. However, owners fear that mechanised log-making may cause value losses, due to poor length measurement, log surface
damage and improper grading. This study compared the performance of manual and mechanised log-making on ten commercial operations,
in order to determine the occurrence and the severity of possible value losses due to product degrade. The study found that
length measurement errors are smaller for mechanised processing, while the frequency and severity of log surface damage are
the same for both treatments. In three cases out of five, mechanised log-making extracted the same value from the stems as
manual log-making: in the remaining two, differences were very small and went opposite directions. Significant differences
were found between operators, stressing the importance of operator skills and motivation. In fact, the log-making specifications
and the pricing structure applied to poplar processing are relatively simple and are unlikely to challenge the ability of
personnel and equipment. At present, most Italian poplar growers are unaware of the potential offered by modern technology,
whose intelligent use would boost value recovery and decrease harvesting cost. Significant benefits may derive from the introduction
of optimised bucking, which may help shifting to a more articulated and rewarding product strategy. 相似文献
43.
Cunha SC Aguero C Damico CB Corgozinho KB Souza HJ Pimenta AL Marassi CD 《Journal of Feline Medicine and Surgery》2011,13(3):205-207
CLINICAL SUMMARY: A 7-month-old female Persian cat presented with gastrointestinal (GI) necrosis and perforation caused by Rhizomucor species. Unfortunately, the cat died of bacterial peritonitis and sepsis before a definitive diagnosis, based on histopathology and fungal culture, was achieved. PRACTICAL RELEVANCE: This appears to be the first reported case of GI disease caused by Rhizomucor species in a cat. Mucorales infections typically cause acute and rapidly progressive disease. As illustrated by this case, clinicians should be alert to the potentially fatal consequences of an opportunistic Rhizomucor species infection in their feline patients. 相似文献
44.
Nuchi CD Hernandez P McClements DJ Decker EA 《Journal of agricultural and food chemistry》2002,50(19):5445-5449
Lipid hydroperoxides are important factors in lipid oxidation due to their ability to decompose into free radicals. In oil-in-water emulsions, the physical location of lipid hydroperoxides could impact their ability to interact with prooxidants such as iron. Interfacial tension measurements show that linoleic acid, methyl linoleate, and trilinolein hydroperoxides are more surface-active than their non-peroxidized counterparts. In oil-in-water emulsion containing surfactant (Brij 76) micelles in the continuous phase, linoleic acid, methyl linoleate, and trilinolein hydroperoxides were solubilized out of the lipid droplets into the aqueous phase. Brij 76 solubilization of the different hydroperoxides was in the order of linoleic acid > trilinolein > or = methyl linoleate. Brij 76 micelles inhibited lipid oxidation of corn oil-in-water emulsions with greater inhibition of oxidation occurring in emulsions containing linoleic acid hydroperoxides. Surfactant solubilization of lipid hydroperoxides could be responsible for the ability of surfactant micelles to inhibit lipid oxidation in oil-in-water emulsions. 相似文献
45.
Supercritical carbon dioxide extraction and characterization of Laurus nobilis essential oil 总被引:5,自引:0,他引:5
Caredda A Marongiu B Porcedda S Soro C 《Journal of agricultural and food chemistry》2002,50(6):1492-1496
Supercritical carbon dioxide extraction allowed essential oil of Laurus nobilis to be obtained. Extraction conditions were as follows: pressure, 90 bar; temperature, 50 degrees C; and carbon dioxide flow, Phi = 1.0 kg/h. Waxes were entrapped in the first separator set at 90 bar and -10 degrees C. The oil was recovered in the second separator working at 15 bar and 10 degrees C. The main components were 1,8-cineole (22.8%), linalool (12.5%), alpha-terpinyl acetate (11.4%), and methyleugenol (8.1%). Comparison with the hydrodistilled oil did not reveal any significant difference. Collection of samples at different extraction times during supercritical extraction allowed the change of the oil composition to be monitored. Lighter compounds such as hydrocarbon and oxygenated monoterpenes were extracted in shorter times than the heavier hydrocarbon and oxygenated sesquiterpenes. 相似文献
46.
Felicissimo MP Bittencourt C Houssiau L Pireaux JJ 《Journal of agricultural and food chemistry》2004,52(7):1810-1814
Three different experiments were performed in order to obtain the major carotenoid composition of the natural colorant annatto (E160b) through ToF-SIMS (time-of-flight secondary ion mass spectrometry) and XPS (X-ray photoelectron spectroscopy) analyses. In the first experiment, Bixa orellana seeds aril as well as its interior part were analyzed. The analysis of the seeds aril by ToF-SIMS gives the colorant fingerprint without any sample treatment, showing the presence of bixin and its characteristic fragments. The analysis performed in the interior part of the seeds indicates the presence of Fe. The second set of measurements was conducted on the seeds organic extract right after extraction revealing the same components observed by in situ measurement. A third set of measurements was performed aiming to determine the reason for the organic extract color shift observed after 3 months of exposure to ambient light at room temperature. In this case, it was possible to evidence the degradation of bixin by the loss of xylene molecules through ToF-SIMS and the probable carotenoid oxidation based on the C1s XPS spectrum of the degraded extract. 相似文献
47.
Bittencourt C Felicissimo MP Pireaux JJ Houssiau L 《Journal of agricultural and food chemistry》2005,53(16):6195-6200
Bixa orellana fruit extracts were studied by time-of-flight secondary ion mass spectrometry (ToF-SIMS). The intensity of the peak at m/z 396, assigned to the bixin molecular ion plus two hydrogen atoms (C25H(32)O(4+), decreased as the extract was heated and nearly disappeared with heating above 150 degrees C. Simultaneously, the formation of dimers at m/z 790, 804, and 818 was observed. The ToF-SIMS spectrum is characterized by a large amount of peaks generated by the principal ions and their multiple fragmentation patterns. To extract maximum information from the data set, multivariate statistical analysis was applied. Principal component analysis revealed important structural changes of the bixin molecule upon heating at different temperatures. This information can be used by the food industry as by controlling the temperature of the heating process the red/yellow balance of this colorant can be tuned. 相似文献
48.
Niza-Ribeiro J Pereira A Souza J Madeira H Barbosa A Afonso C 《Preventive veterinary medicine》2005,72(1-2):81-5; discussion 215-9
A study to evaluate BVDV-prevalence, recent -contact and -vaccine use in dairy herds in the "Entre Douro e Minho" (EDM) region in North Portugal was carried out in 124 dairy herds in 2003. Herds were visited to ascertain BVDV-vaccine use and to collect a bulk tank milk (BTM) sample and serum from 1268 cattle to analyse BVDV-antibodies using an NS2-3 ELISA. Fifty-three percent of farmers used inactivated BVDV-vaccines whilst the remaining farmers were not presently using BVDV-vaccines. BMT-antibody results included 35% positives, 25% negative and 39% inconclusive, and were similar in vaccinated and non-vaccinated herds (p>0.05) and allowed estimating a 10% BVDV herd-prevalence from prior knowledge of the relationship between BMT-antibody results and probability of PI cattle in the herd. Overall individual seroprevalence was 27% and was 23% in non-vaccinated and 36% in vaccinated cattle (p<0.05). Contact of the herd with BVDV was assessed according to seroprevalence in young and adult cattle in the herd and it was estimated that 35% of herds were infected or had recent contact with BVDV, 40% were not infected and did not have recent contact with BVDV and the BVDV-infection and -contact status of remaining herds was undetermined. The results from this study indicate BVDV is endemic and BVDV-vaccines are widespread in the dairy-cattle population in EDM region in Portugal. 相似文献
49.
The copulatory behavior and the parvocellular vasotocin (VT) system of the nucleus of the stria terminalis (BST) are sexually dimorphic in the Japanese quail. Embryonic administration of estradiol benzoate (EB) induces an organizational effect determining the disappearance of such a dimorphism (male shows behavior and cerebral phenotype of the female). The VT parvocellular system can therefore be considered an accurate marker of the sexual differentiation of brain circuits and a very sensitive indicator of the activity of estrogen-like substances on neural circuits. To test this hypothesis we administered diethylstilbestrol (DES), a powerful synthetic xenoestrogen, genistein (GEN), a phytoestrogen produced by soy, and bisphenol A (BPA). After 3 days of incubation, quail eggs were injected with vehicle, EB, DES, GEN or BPA. Administration of BPA caused an early blockage of development and no further analyses were done on the BPA groups. At puberty, the copulatory behavior of EB- or DES-treated male quail was totally abolished, whereas only the highest doses of GEN determined a significant decrease of the behavior. After the tests, the animals were sacrificed and perfused. The fractional area (FA) covered by VT immunoreactivity was analyzed in BST, medial preoptic nucleus, and lateral septum by computerized image analysis. The FA was significantly reduced after treatment with EB, DES and GEN at high doses. These results confirm that the sexually dimorphic VT system of the Japanese quail is a sensible indicator of the effects of xenoestrogens at the level of the central nervous system. 相似文献