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61.
62.
This article will contextualize ethnographic and clinicalfeatures that distinguish one particular alternativehealing method (Self-Acceptance Training) frommainstreampsychotherapeutic procedures. Factors common to manypsychotherapies are listed and a series of contrasts andcomparisons made by examining definitions of: (1) presentingproblems, (2) inciting events, (3) phasic development, (4)taxonomic classifications, (5) therapeutic interventions,and (6) prognostic formulations. The alternative method oftreatment described in a companion publication(SAT) is used to makesome specific comparisons (Zatzick and Johnson 1997).Baschs (1980) concise recording of a dynamic therapy isborrowed for purposes of a comparative hypothetical treatmentof his patient through a Self-Acceptance Training session.Some directions for future work are suggested. 相似文献
63.
Measurements focused on seasonal contribution of rice productivity to methane emission were made in three experiments conducted in Texas flooded paddy soils during 1994 and 1995 growing seasons. A total of five rice cultivars representing two distinct groups in methane emission were involved. Over a 10-week period after permanent flooding, total seasonal methane emission was positively correlated with rice above-ground biomass ( r 2 = 0.845, n = 11). A very strong dependence of daily methane emission on above-ground vegetative biomass ( r 2 = 0.887, n = 93) and on root biomass ( r 2 = 0.816, n = 33) was also observed. Calculation from three developmental periods (vegetative, reproductive and ripening) of rice plant indicated that more than 75% of total seasonal methane was emitted during the last 5-week period in concert with reproductive and ripening stages, while rice biomass production during the same period amounted to ≈ 50% of the seasonal total. According to the correlation of cumulative methane emission with above-ground biomass increment between every two-week interval ( r 2 = 0.490, n = 93, P = 0.000), the carbon released as methane is approximately equivalent to 3% and 4.5% of photosynthetically fixed carbon in the biomass for low and high emission cultivars, respectively. A further investigation showed that these fractions are related to plant growth and development. The carbon ratio of methane emitted to net photosynthetic production during vegetative, reproductive, and ripening periods averaged 0.9%, 3.6% and 7.9%, respectively, for low emission cultivars, and 2.0%, 5.0% and 8.3%, respectively, for high emission cultivars. Moreover, the ratio was strongly dependent on plant biomass, resulting in r 2 values from 0.775 to 0.907. 相似文献
64.
MIGUEL VENCES STEFAN WANKE DAVID R. VIEITES WILLIAM R. BRANCH FRANK GLAW AXEL MEYER 《Biological journal of the Linnean Society. Linnean Society of London》2004,83(1):115-130
Several house gecko species of the genus Hemidactylus are almost cosmopolitan lizards, with distributions that have probably been shaped by natural transoceanic dispersal as well as by more recent human introductions. Here we revise the Hemidactylus populations of Madagascar and compare them genetically with populations from other sites in the Indian Ocean region. Morphological data strongly confirm the occurrence of three Hemidactylus species on Madagascar: Hemidactylus frenatus , distributed along the western coast of Madagascar; H. platycephalus , restricted to the north-west and the widespread H. mercatorius that occurs throughout the island, including coastal areas at sea level as well as big cities (Antananarivo, Fianarantsoa) at altitudes of 1200–1300 m above sea level. Analyses of partial sequences of the 16S rRNA gene in 46 Hemidactylus specimens from Madagascar, East Africa, South Asia, and the Comoro and Mascarene archipelagos demonstrated the presence of a fourth species, H. brooki, on the Mascarenes (Réunion, Rodrigues, and Mauritius) and Comoros (Moheli). The Malagasy populations of H. platycephalus were genetically uniform and differentiated from the African and Comoroan specimens studied. H. frenatus had a relatively low genetic differentiation over the whole region with no recognizable phylogeographical structure, indicating more recent colonizations or introductions. In contrast, H. mercatorius showed a strong phylogeographical structure of haplotypes, with two distinctly different lineages in Madagascar. Moreover, all Malagasy specimens differed strongly from the single African specimen included. This indicates that populations of H. mercatorius in Madagascar have a long history that predates human settlement. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 83 , 115–130. 相似文献
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66.
KATHLEEN M. O'CONNELL S. H. HUTNER HUGUETTE FROMENTIN OSCAR FRANK HERMAN BAKER 《The Journal of eukaryotic microbiology》1968,15(4):719-724
SYNOPSIS. Cryoprotectants were tested in both complex and semidefined media for the trypanosomatid Crithidia fasciculata. Near log-phase or end-of-log-phase cultures were frozen for 24–48 hr at ∼ -20 C, then warmed in air to room temperature. Immediate motility was correlated with viability. The best protectant of the 83 tested was glycerol at ∼ 10% (w/v). Survival without cryoprotectant was rare. Outstanding cryoprotectants (perhaps also useful solvents for drugs poorly soluble in water) were: ethylene glycol; 2,2'-dioxyethanol (diethylene glycol); 1,2,4-butanetriol; 1,4-cyclohexanediol; dimethylsulfoxide; propylene glycol; and N -acetylethanolamine. Several sugars were active, e.g., D-arabinose, sucrose, and sorbitol. Trypanosomes tolerated cryoprotectants much less; tolerance was better in growth media than in suspension media. Trypanosoma gambiense was grown in blood-enriched media + 2-2.5% glycerol, suspended in 20% (w/v) glycerol. then frozen; this permitted 3-week survival. T. conorhini survived 4 weeks after growth in media containing glycerol 2.5%+ ethylene glycol 4%+ rutin 1.0 mg per 100 ml. 相似文献
67.
Sky islands provide ideal opportunities for understanding how climatic changes associated with Pleistocene glacial cycles influenced species distributions, genetic diversification, and demography. The salamander Plethodon ouachitae is largely restricted to high‐elevation, mesic forest on six major mountains in the Ouachita Mountains. Because these mountains are separated by more xeric, low‐elevation valleys, the salamanders appear to be isolated on sky islands where gene flow among populations on different mountains may be restricted. We used DNA sequence data along with ecological niche modelling and coalescent simulations to test several hypotheses related to diversifications in sky island habitats. Our results revealed that P. ouachitae is composed of seven well‐supported lineages structured across six major mountains. The species originated during the Late Pliocene, and lineage diversification occurred during the Middle Pleistocene in a stepping stone fashion with a cyclical pattern of dispersal to a new mountain followed by isolation and divergence. Diversification occurred primarily on an east–west axis, which is likely related to the east–west orientation of the Ouachita Mountains and the more favourable cooler and wetter environmental conditions on north slopes compared to south‐facing slopes and valleys. All non‐genealogical coalescent methods failed to detect significant population expansion in any lineages. Bayesian skyline plots showed relatively stable population sizes over time, but indicated a slight to moderate amount of population growth in all lineages starting approximately 10 000–12 000 years ago. Our results provide new insight into sky island diversifications from a previously unstudied region, and further demonstrate that climatic changes during the Pleistocene had profound effects on lineage diversification and demography, especially in species from environmentally sensitive habitats in montane regions. 相似文献
68.
JEFF A. JOHNSON† RUTH E. TINGAY‡ MELANIE CULVER§ FRANK HAILER¶ MICHÈLE L. CLARKE†† DAVID P. MINDELL‡‡ 《Molecular ecology》2009,18(1):54-63
The critically endangered Madagascar fish-eagle ( Haliaeetus vociferoides ) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100–120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite loci were compared with its sister species, the African fish-eagle ( Haliaeetus vocifer ), and 16 of these loci were also characterized in the white-tailed eagle ( Haliaeetus albicilla ) and the bald eagle ( Haliaeetus leucocephalus ). Overall, extremely low genetic diversity was observed in the Madagascar fish-eagle compared to other surveyed Haliaeetus species. Determining whether this low diversity is the result of a recent bottleneck or a more historic event has important implications for their conservation. Using a Bayesian coalescent-based method, we show that Madagascar fish-eagles have maintained a small effective population size for hundreds to thousands of years and that its low level of neutral genetic diversity is not the result of a recent bottleneck. Therefore, efforts made to prevent Madagascar fish-eagle extinction should place high priority on maintenance of habitat requirements and reducing direct and indirect human persecution. Given the current rate of deforestation in Madagascar, we further recommend that the population be expanded to occupy a larger geographical distribution. This will help the population persist when exposed to stochastic factors (e.g. climate and disease) that may threaten a species consisting of only 200 adult individuals while inhabiting a rapidly changing landscape. 相似文献
69.
JOHN M. TIRPAK D. TODD JONES-FARRAND FRANK R. THOMPSON III DANIEL J. TWEDT CHARLES K. BAXTER JANE A. FITZGERALD WILLIAM B. UIHLEIN III 《The Journal of wildlife management》2009,73(8):1307-1315
ABSTRACT Emerging methods in habitat and wildlife population modeling promise new horizons in conservation but only if these methods provide robust population-habitat linkages. We used Breeding Bird Survey (BBS) data to verify and validate newly developed habitat suitability index (HSI) models for 40 priority landbird species in the Central Hardwoods and West Gulf Coastal Plain/Ouachitas Bird Conservation Regions. We considered a species’ HSI model verified if there was a significant rank correlation between mean predicted HSI score and mean observed BBS abundance across the 88 ecological subsections within these Bird Conservation Regions. When we included all subsections, correlations verified 37 models. Models for 3 species were unverified. Rank correlations for an additional 5 species were not significant when analyses included only subsections with BBS abundance >0. To validate models, we developed generalized linear models with mean observed BBS abundance as the response variable and mean HSI score and Bird Conservation Region as predictor variables. We considered verified models validated if the overall model was an improvement over an intercept-only null model and the coefficient on the HSI variable in the model was >0. Validation provided a more rigorous assessment of model performance than verification, and models for 12 species that we verified failed validation. Species whose models failed validation were either poorly sampled by BBS protocols or associated with woodland and shrubland habitats embedded within predominantly open landscapes. We validated models for 25 species. Habitat specialists and species reaching their highest densities in predominantly forested landscapes were more likely to have validated models. In their current form, validated models are useful for conservation planning of priority landbirds and offer both insight into limiting factors at ecoregional scales and a framework for monitoring priority landbird populations from readily available national data sets. 相似文献
70.
COLIN J. YATES JANE ELITH ANDREW M. LATIMER DAVID LE MAITRE GUY F. MIDGLEY FRANK M. SCHURR ADAM G. WEST 《Austral ecology》2010,35(4):374-391
Increasing evidence shows that anthropogenic climate change is affecting biodiversity. Reducing or stabilizing greenhouse gas emissions may slow global warming, but past emissions will continue to contribute to further unavoidable warming for more than a century. With obvious signs of difficulties in achieving effective mitigation worldwide in the short term at least, sound scientific predictions of future impacts on biodiversity will be required to guide conservation planning and adaptation. This is especially true in Mediterranean type ecosystems that are projected to be among the most significantly affected by anthropogenic climate change, and show the highest levels of confidence in rainfall projections. Multiple methods are available for projecting the consequences of climate change on the main unit of interest – the species – with each method having strengths and weaknesses. Species distribution models (SDMs) are increasingly applied for forecasting climate change impacts on species geographic ranges. Aggregation of models for different species allows inferences of impacts on biodiversity, though excluding the effects of species interactions. The modelling approach is based on several further assumptions and projections and should be treated cautiously. In the absence of comparable approaches that address large numbers of species, SDMs remain valuable in estimating the vulnerability of species. In this review we discuss the application of SDMs in predicting the impacts of climate change on biodiversity with special reference to the species‐rich South West Australian Floristic Region and South African Cape Floristic Region. We discuss the advantages and challenges in applying SDMs in biodiverse regions with high levels of endemicity, and how a similar biogeographical history in both regions may assist us in understanding their vulnerability to climate change. We suggest how the process of predicting the impacts of climate change on biodiversity with SDMs can be improved and emphasize the role of field monitoring and experiments in validating the predictions of SDMs. 相似文献