46 research outputs found

    The Effect of Recurrent Floods on Genetic Composition of Marble Trout Populations

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    A changing global climate can threaten the diversity of species and ecosystems. We explore the consequences of catastrophic disturbances in determining the evolutionary and demographic histories of secluded marble trout populations in Slovenian streams subjected to weather extremes, in particular recurrent flash floods and debris flows causing massive mortalities. Using microsatellite data, a pattern of extreme genetic differentiation was found among populations (global FST of 0.716), which exceeds the highest values reported in freshwater fish. All locations showed low levels of genetic diversity as evidenced by low heterozygosities and a mean of only 2 alleles per locus, with few or no rare alleles. Many loci showed a discontinuous allele distribution, with missing alleles across the allele size range, suggestive of a population contraction. Accordingly, bottleneck episodes were inferred for all samples with a reduction in population size of 3–4 orders of magnitude. The reduced level of genetic diversity observed in all populations implies a strong impact of genetic drift, and suggests that along with limited gene flow, genetic differentiation might have been exacerbated by recurrent mortalities likely caused by flash flood and debris flows. Due to its low evolutionary potential the species might fail to cope with an intensification and altered frequency of flash flood events predicted to occur with climate change

    Variation revealed by SNP genotyping and morphology provides insight into the origin of the tomato

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    Tomato, Solanum lycopersicum, is divided into two widely distributed varieties: the cultivated S. lycopersicum var. lycopersicum, and the weedy S. lycopersicum var. cerasiforme. Solanum pimpinellifolium is the most closely related wild species of tomato. The roles of S. pimpinellifolium and S. l. cerasiforme during the domestication of tomato are still under debate. Some authors consider S. l. cerasiforme to be the ancestor, whereas others think that S. l. cerasiforme is an admixture of S. pimpinellifolium and the cultivated S. l. lycopersicum. It is also not clear whether the domestication occurred in the Andean region or in Mesoamerica. We characterized 272 accessions (63 S. pimpinellifolium, 106 S. l. cerasiforme, 95 S. l. lycopersicum and 8 derived from hybridization processes) were morphologically and genetically using the SolCap platform (7,414 SNPs). The two species were distinguished in a PCA analysis and displayed a rich geographic structure. Solanum lycopersicum var. cerasiforme and S. l. lycopersicum were also differentiated in the PCA and Structure analyses, which supports maintaining them as different varieties. Solanum pimpinellifolium and the Andean S. l. cerasiforme were more diverse than the non-Andean S. lycopersicum. Solanum lycopersicum var. cerasiforme was morphologically and molecularly intermediate between S. pimpinellifolium and tomato. Solanum lycopersicum var. cerasiforme, with the exception of several Ecuadorian and Mexican accessions, is composed of the products of admixture processes according to the Structure analysis. The non-admixtured S. l. cerasiforme might be similar to the ancestral cultivars from which the cultivated tomato originated, and presents remarkable morphological diversity, including fruits of up to 6 cm in diameter. The data obtained would fit a model in which a pre-domestication took place in the Andean region, with the domestication being completed in Mesoamerica. Subsequently, the Spaniards took plants from Mesoamerica to Spain and from there they were exported to the rest of the world.Blanca Postigo, JM.; Cañizares Sales, J.; Cordero Romay, L.; Pascual Bañuls, L.; Díez Niclós, MJTDJ.; Nuez Viñals, F. (2012). Variation revealed by SNP genotyping and morphology provides insight into the origin of the tomato. PLoS ONE. 7(10):1-17. doi:10.1371/journal.pone.0048198S11771

    Internet-based cognitive therapy for social anxiety disorder in Hong Kong: therapist training and dissemination case series

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    Background: Guided internet-based psychological interventions show substantial promise for expanding access to evidence-based mental health care. However, this can only be achieved if results of tightly controlled studies from the treatment developers can also be achieved in other independent settings. This dissemination depends critically on developing efficient and effective ways to train professionals to deliver these interventions. Unfortunately, descriptions of therapist training and its evaluation are often limited or absent within dissemination studies. Objective: This study aimed to describe and evaluate a program of therapist training to deliver internet-based Cognitive Therapy for social anxiety disorder (iCT-SAD). As this treatment was developed in the United Kingdom and this study was conducted in Hong Kong with local therapists, an additional objective was to examine the feasibility, acceptability, and initial efficacy of iCT-SAD in this cultural context, based on data from a pilot case series. Methods: Training in iCT-SAD was provided to 3 therapists and included practice of the face-to-face format of therapy under clinical supervision, training workshops, and treating 6 patients with the iCT-SAD program. Training progress was evaluated using standardized and self-report measures and by reviewing patient outcomes. In addition, feedback from patients and therapists was sought regarding the feasibility and acceptability of the program. Results: The training program was effective at increasing therapists’ iCT-SAD knowledge and skills, resulting in levels of competence expected of a specialist Cognitive Behavioral Therapy practitioner. The 6 patients treated by the trainees all completed their treatment and achieved a mean pre- to posttreatment change of 53.8 points (SD 39.5) on the primary patient outcome measure, the Liebowitz Social Anxiety Scale. The within-group effect size (Cohen d) was 2.06 (95% CI 0.66-3.46). There was evidence to suggest that the patients’ clinical outcomes were sustained at 3-month follow-up. These clinical results are comparable to those achieved by UK patients treated by the developers of the internet program. Patient and therapist feedback did not identify any major cultural barriers to implementing iCT-SAD in Hong Kong; some modest language suggestions were made to assist understanding. Conclusions: The therapist training implemented here facilitated the successful dissemination of an effective UK-developed internet intervention to Hong Kong. The treatment appeared feasible and acceptable in this setting and showed highly promising initial efficacy. A randomized controlled trial is now required to examine this more robustly. As therapist training is critical to the successful dissemination of internet interventions, further research to develop, describe, and evaluate therapist training procedures is recommended.</br

    Disturbances of Uric Acid Metabolism

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