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61.
Southeast Asia is one of the richest reservoirs of biodiversity on earth and home to one of the highest concentrations of endemic species. Many protected areas (PA) have been established across the region, but to date no systematic evaluation of their efficacy has been published because no comprehensive dataset was available which could be fed into an analysis of conservation gaps. We collected the geographic range for 1086 mammal species of Southeast Asia and we built species-specific habitat suitability models for 901 of them. We performed two gap analyses (one based on a combination of distribution models and distribution ranges and one based on distribution ranges only) for each mammalian species, to evaluate the effectiveness of the existing network of PA and to identify priority regions and priority species for expanding and consolidating the network. Our results indicate that 7.5-8.2% of species are not covered by any PA, and 51.6-59.1% are covered only partially. These species are distributed throughout the entire study area and their conservation requires the creation of new PA that can help fill this existing conservation gap. This would be particularly important for species which are endemic of small islands, where species survival is often threatened by the presence of introduced species and habitat conversion. Yet PAs cannot be considered as the ending point of a conservation strategy, because overall, 34% of the species we analyzed (many of which already covered by existing PAs) were at risk of extinction when considering the IUCN red-list criteria. PAs should therefore be considered in a broader framework of all local ecological and socio-economic trends, including the growing human population, growing economy and infrastructure development. 相似文献
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63.
C. Douart L. Briand E. Betti D. Bencharif D. Tainturier 《Anatomia, histologia, embryologia》2015,44(1):22-36
In mammals, the liver undergoes a series of spectacular anatomical changes during development, particularly in domestic ruminants. In all domestic mammals, the liver retracts cranially until it reaches its definitive diaphragmatic position; however, in the sheep, it also withdraws from the entire left side of the diaphragm and seems to rotate through 180°. An anatomical study reveals that the hepatic conformation evolves very little during this topographical change. The latter occurs in two phases: an initial phase of marked regression of the left lobe, which starts from the beginning of the foetal period (44th day of gestation), followed by marked regression of the entire liver, which starts between the 90th and 117th days and ends between the 2nd and 3rd month of life. The path of hepatic regression is dictated by the particular layout of the liver's attachments in the sheep. The left triangular ligament, which holds the L lobe to the left in other species, is almost completely absent in the sheep, whilst the right lobe is fixed to the top of the diaphragm. As the liver regresses, the right lobe therefore draws the left lobe with it to the right‐hand side. A statistical study shows constant regression of the hepatic surface area during the topographical evolution of the liver, with a particularly marked and sudden reduction between the end of the 4th month and the middle of the 5th month of gestation. It also shows that the regression of the left lobe is consistently greater than that of the right lobe and that the topographical regression of the liver cannot be predicted by measuring the weight of the liver, which behaves independently to the surface area of the liver. 相似文献
64.
Trichinella zimbabwensis in wild reptiles of Zimbabwe and Mozambique and farmed reptiles of Ethiopia
Pozio E Foggin CM Gelanew T Marucci G Hailu A Rossi P Morales MA 《Veterinary parasitology》2007,143(3-4):305-310
In 1995, a new species of Trichinella (Trichinella zimbabwensis) was discovered in farmed Nile crocodiles (Crocodylus niloticus) in Zimbabwe, where the mode of transmission was the consumption of the meat of slaughtered crocodiles, used as feed. To determine whether T. zimbabwensis affects poikilotherm vertebrates in the wild, monitor lizards (Varanus niloticus) and Nile crocodiles were collected in Zimbabwe and Mozambique. In 5 (17.6%) of the 28 monitor lizards from Zimbabwe, T. zimbabwensis larvae were identified. For the wild Nile crocodiles from Mozambique, species-level identification was not possible, yet immunohistochemical analysis revealed that 8 (20%) of the 40 animals harboured non-encapsulated Trichinella sp. larvae, which probably belonged to T. zimbabwensis. This is the first report of T. zimbabwensis in wild reptiles, and the findings are consistent with reports that vertebrates with scavenger and cannibalistic behaviour are the most important hosts of Trichinella spp. The wide distribution of monitor lizards and crocodiles in Africa and the development of national crocodile breeding programs in many African countries should be taken into consideration when evaluating the risk of transmission of this parasite to mammals, including humans. 相似文献
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Domenico Lafiandra Francesco Sestili Renato D'Ovidio Michela Janni Ermelinda Botticella Gianluca Ferrazzano Marco Silvestri Roberto Ranieri Enzo DeAmbrogio 《Cereal Chemistry》2010,87(1):28-34
Manipulation of starch composition in cereals and particularly in wheat is receiving increasing attention due to recognition of its important role in food and nonfood applications. The amylose/ amylopectin ratio influences the physicochemical properties of starches and nutritional value of derived end products. Identification of the key enzymes involved in the starch biosynthetic pathway has opened new avenues for altering the amylose and amylopectin content in durum and bread wheat. The granule bound starch synthases (GBSSI), or waxy proteins, are the enzymes responsible for amylose synthesis in storage tissues; amylopectin is produced by the concerted action of different enzymes, including starch synthases (SS), branching (SBE), and debranching enzymes (DBE). By altering the level of key enzymes involved in the regulation of starch synthesis, it is possible to generate novel starches with unique functional properties. In this respect, both low and high amylose starches are particularly interesting because they are associated with industrial and processing properties as well as with human health and nutrition. So far, major attention has addressed the manipulation of starch composition in bread wheat, whereas durum wheat has been investigated to a much lesser extent. Approaches currently available to alter amylose/amylopectin ratio and tailor starch composition in durum wheat are presented. 相似文献
67.
Pozio E Mesina P Sechi F Pira M Liciardi M Cossu P Marucci G Garippa G Firinu A 《Veterinary parasitology》2006,140(1-2):177-180
Trichinella sp. infection has been documented in both humans and animals in most Mediterranean countries, yet in the past 60 years no infections have been reported on the Mediterranean islands. We describe the first outbreak of Trichinella sp. infection to have been reported on the island of Sardinia. The outbreak occurred in two villages in 2005 and involved 11 persons who had eaten raw sausages made from the same free-ranging sow. All 11 persons developed signs and symptoms of trichinellosis and seroconverted within 48 days of consuming the infected meat. The etiological agent was Trichinella britovi. Sardinia, like all Mediterranean islands, had been considered to be Trichinella-free. The present report, together with a recent report of T. britovi infection in animals on the nearby island of Corsica (France), raises questions as to the validity of the concept of Trichinella-free areas or regions. 相似文献
68.
Bordoni R Germini A Mezzelani A Marchelli R De Bellis G 《Journal of agricultural and food chemistry》2005,53(4):912-918
We recently developed a multiplex polymerase chain reaction (PCR) system for the simultaneous detection of four transgenic maize (MON810, Bt176, Bt11, and GA21), one transgenic soybean (Roundup Ready), and two control genes (lectin and zein). Because PCR can lead to ambiguous interpretations due to low specificity, we have developed the ligation detection reaction (LDR) combined with a universal array as a molecular tool to confirm results of PCR analysis. Here, we describe the PCR-LDR-universal array procedure and demonstrate its specificity in revealing the presence of transgenic DNA in experimental samples, raw materials, and commercial foodstuffs. 相似文献
69.
Background
Daylight saving time is widely adopted. Little is known about its influence on the daily rest-activity cycles. We decided to explore the effects of transition into daylight saving time on the circadian rhythm of activity. 相似文献70.
Sea bream (Sparus aurata) production plays a significant part in Italian aquaculture, contributing to almost 18% of national pisciculture sales revenue. In recent years, Italian firms faced higher competition from countries with lower production costs. This prompted responses toward both cost reduction and product differentiation. The objective of this study was to investigate the preferences of Italian consumers for sea bream from fish farms, with a focus on aspects of product differentiation as gleaned from the analysis of the market situation: price, product origin, type and place of fish farming, and, in particular, type of feed. Data were collected with a consumers’ survey using personal interviews conducted on a questionnaire that included a choice experiment. Consumer preferences were analyzed with choice models based on stated preference data. The models made it possible to evaluate the potential of products with different combinations of attributes for which there is currently no market information available. In particular, the country of origin emerged as an important element of consumer choice, and to a lesser degree, organic certification and fish farming in marine cages also play a relevant role and may command a price premium. 相似文献