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41.
Reintroductions are a common strategy to restore ecosystem integrity, especially when top predators are involved. Reintroductions are often time consuming, expensive, and controversial, and thus understanding what aspects are important for a successful program is needed. Focusing on the example of the reintroduction of Canada lynx (Lynx canadensis) to Colorado, we investigated how different release protocols (RP) affected mortality within the first year post-release. We found that average monthly mortality in the study area during the first year decreased with time in captivity from 0.205 (95% CI = 0.069, 0.475) for lynx having spent up to 7 days in captivity to 0.028 (95% CI = 0.012, 0.064) for lynx spending >45 days in captivity before release. Our results also suggest that keeping lynx in captivity beyond 5–6 weeks accrued little benefit in terms of monthly survival. We found that, on a monthly average basis, lynx were as likely to move out (P = 0.196, SE = 0.032) as well as back onto (P = 0.143, SE = 0.034) the reintroduction area during the first year after release. Mortality was 1.6 times greater outside of the study area, suggesting that permanent emigration and differential mortality rates on and off reintroduction areas should be factored into sample size calculations for an effective reintroduction effort. A post-release monitoring plan is critical to providing information to assess aspects of RP and to improve survival of individuals. Future lynx and other carnivore reintroductions may use our results to help design reintroduction programs including both the release and post-release monitoring protocols. © 2011 The Wildlife Society.  相似文献   
42.
Reintroductions have increasingly become effective at restoring populations of imperiled native wildlife. How animals are reintroduced into unfamiliar environments may have pronounced impacts on behavior, survival, and reproduction. We evaluated the influence of four release methods on survival rates of translocated swift foxes at Bad River Ranches (BRR) in western South Dakota: (1) hard‐release, (2) short‐soft‐release, (3) long‐soft‐release, and (4) captive born. A total of 179 foxes captured in Wyoming during 2002–2007 and in Colorado during 2006–2007 were released into BRR and the surrounding area. In addition, 43 pups born to foxes in the long‐soft‐release category were also released. All release methods incorporated a 14‐ to 21‐day quarantine period. Hard‐release foxes were released directly from a transport kennel, whereas short‐soft‐release foxes were released from soft‐release pens by opening the door and allowing the foxes to leave voluntarily. Long‐soft‐release foxes were held for more than 250 days on‐site in soft‐release pens through the winter and released in the following year in early summer. During 2002–2007, survival of reintroduced foxes differed significantly (p < 0.05) by age (adult vs. juvenile), release year, and release method. The short‐soft‐release method had the highest 60‐day post‐release survival probability compared with the other release methods. We did not detect any differences in mortality hazards between wild‐born and short‐soft‐release foxes. Reintroduction programs based on short‐soft‐releases are useful for restoring or augmenting populations to advance the conservation of the swift fox.  相似文献   
43.
Thomas PS  Babu GS  Anusha RL  Shetty S 《Gerodontology》2012,29(2):e1241-e1243
Malignant melanoma is the least common but most deadly of all primary skin cancers. Oral malignant melanoma is a rare aggressive neoplasm usually seen in middle aged persons. This malignancy is more frequently seen on the hard palate and gingiva. Oral melanomas are associated with very poor prognosis because of the tendency to metastasise or invade tissues locally more readily than other malignant tumours of the oral cavity especially in the case of a geriatric patient. The surgical approach, combined with the chemotherapy, is the first choice treatment. This report highlights a case report of 71-year-old female patient diagnosed and treated surgically for an oral malignant melanoma of the pedunculated variety affecting the hard palate and gingiva with review of literature.  相似文献   
44.
To evaluate the osteogenic potential of novel implant materials, it is important to examine their effect on osteoblastic differentiation. Characterizing the tissue response at the bone-biomaterial interface in vivo at a molecular level would contribute significantly to enhancing our understanding of tissue integration of endosseous implant materials. We describe here a new technique that overcomes difficulties commonly associated with performing immunohistochemistry on undecalcified sawed sections of bone. Sheep mandible specimens were fixed in an ethanol based fixative to maintain adequate antigenicity of the tissue. As a result, it was possible to omit antigen retrieval at high temperature for recovery of antigenicity, and detachment of sections from the slides was avoided. Following dehydration and infiltration, the specimens were embedded in a resin composed of polymethylmethacrylate and polybutylmethacrylate. Polymerization was achieved by adding benzoylperoxide and N,N-dimethyl-toluidine. This resin was selected because it maintained the antigenicity of the tissue, provided adequate properties for cutting 50 µm thick sections, and it facilitated deacrylizing the sawed sections. Acid-resistant acrylic slides were glued to the blocks using an epoxy resin based two-component adhesive to avoid detachment of the slides during the deacrylation procedure. Samples were stained for alkaline phosphatase, type I collagen, osteonectin, osteopontin, osteocalcin and bone sialoprotein. The EnVision + ™ dextran polymer conjugate two-step visualization system was applied for immunohistochemical detection of these bone matrix proteins. This procedure yielded positive staining for the osteogenic markers in cells and matrix components. The protocol described here facilitates the use of immunohistochemistry on resin embedded sawed sections of bone and provides a convenient and reliable method that can be used routinely for immunohistochemical analysis of hard tissue specimens containing implant materials.  相似文献   
45.
Here we have studied how the length of the pyrene-labeled acyl chain (n) of a phosphatidylcholine, sphingomyelin, or galactosylceramide affects the partitioning of these lipids between 1), gel and fluid domains coexisting in bovine brain sphingomyelin (BB-SM) or BB-SM/spin-labeled phosphatidylcholine (PC) bilayers or 2), between liquid-disordered and liquid-ordered domains in BB-SM/spin-labeled PC/cholesterol bilayers. The partitioning behavior was deduced either from modeling of pyrene excimer/monomer ratio versus temperature plots, or from quenching of the pyrene monomer fluorescence by spin-labeled PC. New methods were developed to model excimer formation and pyrene lipid quenching in segregated bilayers. The main result is that partition to either gel or liquid-ordered domains increased significantly with increasing length of the labeled acyl chain, probably because the pyrene moiety attached to a long chain perturbs these ordered domains less. Differences in partitioning were also observed between phosphatidylcholine, sphingomyelin, and galactosylceramide, thus indicating that the lipid backbone and headgroup-specific properties are not severely masked by the pyrene moiety. We conclude that pyrene-labeled lipids could be valuable tools when monitoring domain formation in model and biological membranes as well as when assessing the role of membrane domains in lipid trafficking and sorting.  相似文献   
46.
Many prediction guidelines exist in facial approximation for determining the soft-tissue features of the face, and the reliability of each is generally unknown. This study examines four published and commonly used soft-tissue prediction guidelines for estimating nose projection, two of which also estimate the position of the pronasale. The methods tested are those described by: 1) Gerasimov ([1971] The Face Finder; London: Hutchinson & Co.), using the distal third of the nasal bones and the nasal spine; 2) Krogman ([1962] The Human Skeleton in Forensic Medicine; Springfield: Charles C. Thomas), using the average soft-tissue depth at midphiltrum, plus three times the length of the nasal spine (and a variation of this technique: plus three times the distance of the tip of the nasal spine from the nasal aperture); 3) Prokopec and Ubelaker ([2002] Forensic Sci Commun 4:1-4), using the reflected profile line of the nasal aperture; and 4) George ([1987] J Forensic Sci 32:1305-1330), using a variation of the Goode method. Four identical hard-tissue tracings were made of 59 adult lateral head cephlograms (29 males, mean age 24, SD 10 years; 30 females, mean age 23, SD 5 years) on separate sheets of tracing paper. One soft-tissue tracing was also made for each radiograph. All tracings were marked with three identical reference points. Soft-tissue tracings were isolated from one of us (C.N.S.), who attempted under blind conditions to predict pronasale position and nose projection on the hard-tissue tracings, using the soft-tissue prediction guides above. Actual soft-tissue tracings were then compared to each of the predicted tracings, and differences in projection/pronasale position were measured. Results indicate that for nose projection, methods 3 and 4 performed well, while methods 1 and 2 performed poorly. Features which are most related to nose projection/pronasale are described in this paper, as are regression equations generated from these variables that predict pronasale/nose projection better than the traditional methods mentioned above. The results of this study are significant because they: 1) indicate that the popular facial approximation methods used to build the nose are inaccurate and produce incorrect nose anatomy; and 2) indicate that the new pronasale prediction methods developed here appear to have less error than traditional methods.  相似文献   
47.
The conformational flexibility and the dynamics of -D-Manp-(12)--D-Glcp-OMe have been investigated by Metropolis Monte Carlo (MMC) and Langevin dynamics (LD) simulations. The two simulation techniques employ different force fields, namely the HSEA force field and a CHARMm-based force field. The former shows less conformational flexibility than the latter, in which a multiple energy minima conformational space is sampled. Long-range heteronuclear nuclear magnetic resonance (NMR) coupling constants have been measured by selective excitations of the carbons at the glycosidic linkage. Calculated 3JC, H values from MMC and LD simulations show excellent agreement to those from NMR experiments. The X-ray crystal structure has a conformation within a region of the conformational space populated in both force fields.  相似文献   
48.
Bick. A. 2001. The morphology and ecology of Dipolydora armata (Polychaeta, Spionidae) from the western Mediterranean Sea. — Acta Zoologica (Stockholm) 82 : 177–187
The cosmopolitan spionid Dipolydora armata is a dominant species of epifauna on Thais haemastoma shells in the western Mediterranean Sea. Some characters, particularly number, thickness and arrangement of notopodial spines, were extremely variable among specimens. Three morphological forms were distinguished based on the general appearance of the bundles of spines; one form possesses at least one bundle of stout spines, whereas bundles of medium spines or thinner acicular spines characterise the other forms. Differences in prostomial shape, as well as in the extension and form of the caruncle, were artefacts (preservation or angle of observation). The present study supports D. rogeri as a junior synonym of D. armata. D. armata was regularly found on shells inhabited by hermit crabs ( Calcinus tubularis , Clibanarius erythropus ) and on damaged, empty shells. Abundance, dominance, size frequency, occurrence of larvae and occurrence of regenerated specimens varied, possibly as a result of fouling strategy and recurrent settlements.  相似文献   
49.
Developments of intertidal hard-substrate communities in the Oosterschelde estuary were examined in perpendicular transects between high-water line and low-water line in the period 1982–1992. Prior to the beginning of the Oosterschelde estuary works a typology of communities was established and an overall survey of the estuary was carried out. The communities contain flora (algae) as well as fauna. Due to asphalting of dikes in 1986, much of the surface of several communities has been destroyed. The originally well developed communities with large species-richness have not returned. The small reduction in tidal amplitude due to the construction of the storm-surge barrier had a minor effect on the zonation of communities. In the upper part of the intertidal zone the boundaries of the communities moved 0.5–1.0 m downward in the transects along the dike-slopes. At an average inclination of 18° this means a vertical shift of about 15–30 cm. This reflects the reduction of the tidal amplitude: the high-water line shifted ca 22 cm downward. In a number of places sedimentation has caused a reduction in the number of smaller seaweed species in the lower eulittoral zone. At monitoring locations presence of the original communities is rather unchanged. Rare species like Pelvetia canaliculata, Actinia equina and Gelidium pusillum have been able to maintain quite successfully.  相似文献   
50.
The hard and soft acids and bases (HSAB) principle, which states that hard acids bind preferentially to hard bases and soft acids to soft bases, may serve to assess specific chemico-biological interactions. As living systems are composed mainly of "hard" elements, molecular events taking place within the cell are dominated by "hard-hard interactions". On this premise, it becomes likely that extraneous "soft" agents are particularly injurious to life. In the HSAB context a selected number of variegated phenomena are briefly discussed qualitatively; these include biocidal actions, heavy metal poisoning, chemical carcinogenesis, some enzymic reactions, and nucleic acid complexations. Although the HSAB principle cannot be used as a tool for mechanistic explanations of biochemical processes, it may provide clues to likely target molecules and the loci of action.  相似文献   
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