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51.
Local community participation and ex situ conservation has the potential to assist the recovery of the endangered Egyptian tortoise, Testudo kleinmanni. We initiated an in situ community‐based conservation and research program from a captive population of T. kleinmanni. We used a captive population of the Egyptian tortoise to train a member of the local community as a research technician and used his indigenous tracking skills and knowledge of the area to collect activity and dietary data on 28 captive tortoises. We overcame problems with illiteracy by creating a data sheet based on symbols and numbers. This data sheet allowed us to use the indigenous knowledge of various people from the community, and employ them in the future. Our local community approach to data collection, in conjunction with a craft program, made the conservation of the Egyptian tortoise more rewarding to the local community by providing a more sustainable form of income than collecting animals for the pet trade. Our multidimensional approach (local community participation as research technicians, craft program, and trust building) for gaining local support eventually led to the rediscovery of wild Egyptian tortoises in North Sinai, which was significant, as this species was presumed extinct in Egypt. We have now shifted our focus to in situ conservation, using the research and local capacity building template developed from this captive population study. Our template can be used by zoos and conservation organizations with small budgets and collections of native species in natural habitats to create similar captive research programs that can be applied to in situ conservation. Zoo Biol 26:397–406, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
52.
Since the first North Sea Conference (1984, Bremen), all countries bordering the North Sea made commitments to reduce discharge of hazardous substances into the North Sea. From Belgium and The Netherlands, large reductions (upto 90) in heavy metal emissions from land-based sources have been reported between 1985 and 2000. Recently, some studies in the Western Scheldt estuary (WS) have shown that total metal concentration in the water, sediments and suspended particles have decreased compared to levels in the 70s. However, data on aquatic organisms is still very limited and it is therefore difficult to confirm whether the reductions in pollution input and generally improving water quality in the WS have a corresponding impact on the levels of heavy metals in aquatic organisms. The current study measured metal concentrations in the soft tissues of mussels, Mytilus edulis (known to be good indicators of environmental metal pollution) during the period 1996–2002. Spatial (salinity and pollution gradients), temporal and seasonal variations were also studied. Results showed a down-stream decreasing trend for the metals studied (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) during all sampling campaigns. There was also a significant seasonal effect on tissue metal concentrations, with a peak observed around spring in both WS and the nearby less polluted Eastern Scheldt (ES). On temporal trends, a clear drop of metals in mussels was observed in the early 80s coinciding with the start of the efforts to reduce chemical pollution input into the North Sea. Since those early reductions, metal concentrations in mussels generally remained unchanged upto mid 90s. However, in recent times metal concentration in mussels have increased significantly, for example Cd in 2002 was almost 10 times the values in 1983 and similar to levels seen during the peak in the 70s. Other metals also increased in the 90s also reaching levels seen in the 70s. As there is no indication of recent increase in metal input into the estuary, we suggest that increased metal concentrations observed in mussels in recent years especially in the upper estuary are most likely a result of changes in physical and chemical speciation and metal bioavailability. Such changes may be caused by changes in some water quality parameters in the estuary (i.e. increased dissolved oxygen, concentration of organic matter), resulting in conditions that favour releases of sediment-bound metals into the water column. The relationship between metal content and season showed very similar annual profiles in the polluted WS and less polluted ES. Thus, seasonal variations in metal concentrations appear to be largely controlled by biological processes, while total body burdens are dependent on environmental levels and bioavailability. 相似文献
53.
《Revista espa?ola de geriatría y gerontología》2016,51(3):159-163
The prevalence of neuropathic pain is difficult to estimate as most studies evaluating chronic pain do not differentiate neuropathic from nociceptive pain. There are only a few studies of neuropathic pain in the elderly, specifically in the oncology population. This article is a non-systematic review of the relevant evidence on the prevalence and aetiopathogenesis of neuropathic cancer pain in the elderly. 相似文献
54.
55.
Nicholas Shea 《Biology & philosophy》2007,22(3):313-331
There is ongoing controversy as to whether the genome is a representing system (Sterelny K., Smith K.C. and Dickson M. 1996.
Biol. Philos. 11: 377–403; Griffiths P.E. 2001. Philos. Sci. 68: 394–412). Although it is widely recognised that DNA carries
information, both correlating with and coding for various outcomes, neither of these implies that the genome has semantic
properties like correctness or satisfaction conditions (Godfrey-Smith P. 2002. In: Wolenski J. and Kajania-Placek K. (eds),
In the Scope of Logic, Methodology, and the Philosophy of Sciences, Vol. II. Kluwer, Dordrecht, pp. 387–400). Here a modified
version of teleosemantics is applied to the genome to show that it does indeed have semantic properties – there is representation
in the genome. The account differs in three respects from previous attempts to apply teleosemantics to genes. It emphasises
the role of the consumer of representations (in addition to their mode of production). It rejects the standard assumption
that genetic representation can be used to explain the course of an organism’s development. And it identifies the explanatory
role played by representational properties of the genome. A striking consequence of this account is that other inheritance
systems could also be representational. Thus, a version of the parity thesis is accepted (Griffiths P.E. 2001. Philos. Sci.
68: 394–412). However, the criteria for being an inheritance system are demanding, so semantic properties are not ubiquitous. 相似文献
56.
In the framework of the palaeogeographical reconstruction of the Western Taurus during Jurassic, the study of northern and eastern boundary of the Taurids started. Detailed facies analysis evidenced the position of the Barla Dag ramp between two elevated areas: the southern rimmed shelf extension of the platform system and the northern neritic-beach-land plain. In the basal biostratigraphical and ecological characteristics of the Balcikhisar volcano-sedimentary sequence, correlated with the Fele outcrop, one genus and three new species of foraminifers have been found: Sievoides kocyigiti n. gen., n. sp. and Mesoendothyra altineriana n. sp. from neritic environment, and Kurnubia feleensis n. sp. from rimmed shelf lagoon. Both carbonate sedimentary deposits are intercalated with spilitic-basalt pillow lava flows. The age of the new three species is Kimmeridgian, controlled by some foraminifer golden hooks. 相似文献
57.
58.
M.A. Mena M.J. Casarejos J.A. Rodríguez-Navarro I. Rodal J.G. de Yebenes 《FEBS letters》2009,583(1):168-174
Parkin mutations produce Parkinson’s disease (PD) in humans and nigrostriatal dopamine lesions related to increased free radicals in mice. We examined the effects of NP7, a synthetic, marine derived, free radical scavenger which enters the brain, on H2O2 toxicity in cultured neurons and glia from wild-type (WT) and parkin null mice (PK-KO).NP7, 5-10 μM, prevented the H2O2 induced apoptosis and necrosis of midbrain neuronal and glial cultures from WT and PK-KO mice. NP7 suppressed microglial activation and the H2O2 induced drop-out of dopamine neurons. Furthermore, NP7 prevented the increased phosphorylation of ERK and AKT induced by H2O2. NP7 may be a promising neuroprotector against oxidative stress in PD. 相似文献
59.
We isolated eight polymorphic microsatellites from the neotropical tree Luehea seemannii for gene flow and genetic structure studies. We used a streptavidin subtractive enrichment technique to develop a library of CA/GT repeats. Eight loci were screened for diversity from 96 individuals from Barro Colorado Island (BCI) and neighbouring Gigante peninsula in Panama. Luehea seemannii shows moderate levels of genetic diversity within these two populations. Allelic richness ranged from four to nine alleles and averaged 6.44 alleles per locus. Average expected heterozygosity was 0.65 on BCI and 0.60 on Gigante. Results are compared to microsatellite data from another wind‐dispersed gap colonizing species common in Panama. 相似文献
60.
The hypoglycemic agent, 2-tetradecylglycidic acid (TDGA), administered in vivo lowered the concentration of plasma glucose and ketone bodies but raised the concentration of liver and plasma triglycerides in 10-day-old suckling rats. Phospholipid and cholesterol content of the plasma and liver were unaffected by drug treatment. TDGA inhibited the in vivo oxidation of [1-14C]palmitate but not that of [1-14C]decanoate. In suckling rat liver perfusion, TDGA totally inhibited ketone body formation from palmitate and depressed ketone body production from decanoate by 20%. Liver ATP and ADP content in the presence of TDGA decreased although this was probably a reflection of the increased triglyceride content of the liver since the was the same as control livers. The results are discussed in relation to the diet and to the inhibition of carnitine acyl transferase in suckling rats. 相似文献