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Several recent studies have shown that amphibian populations may exhibit high genetic subdivision in areas with recent fragmentation and urban development. Less is known about the potential for genetic differentiation in continuous habitats. We studied genetic differentiation of red-backed salamanders (Plethodon cinereus) across a 2-km transect through continuous forest in Virginia, USA. Mark-recapture studies suggest very little dispersal for this species, whereas homing experiments and post-Pleistocene range expansion both suggest greater dispersal abilities. We used six microsatellite loci to examine genetic population structure and differentiation between eight subpopulations of red-backed salamanders at distances from 200 m to 2 km. We also used several methods to extrapolate dispersal frequencies and test for sex-biased dispersal. We found small, but detectable differentiation among populations, even at distances as small as 200 m. Differentiation was closely correlated with distance and both Mantel tests and assignment tests were consistent with an isolation-by-distance model for the population. Extrapolations of intergenerational variance in spatial position (σ2<15 m2) and pair-wise dispersal frequencies (4Nm<25 for plots separated by 300 m) both suggest limited gene flow. Additionally, tests for sex-biased dispersal imply that dispersal frequency is similarly low for both sexes. We suggest that these low levels of gene flow and the infrequent dispersal observed in mark-recapture studies may be reconciled with homing ability and range expansion if dispersing animals rarely succeed in breeding in saturated habitats, if dispersal is flexible depending on the availability of habitat, or if dispersal frequency varies across the geographic range of red-backed salamanders.Heredity (2007) 98, 53–60. doi:10.1038/sj.hdy.6800905; published online 27 September 2006 [ABSTRACT FROM AUTHOR]

Autoimmune bullous diseases are a heterogenous group of diseases characterized by cutaneous and mucosal vesicles and bullae. Diagnosis is based on a combination of clinical, histopathological, and immunofluorescence findings. Current treatment, including vigilant wound care, significantly reduces disease morbidity and mortality. [ABSTRACT FROM AUTHOR]

This descriptive study examines the self-reported behaviors of 285 male and female adolescent children (ages 12-17) of narcotic addicts participating in methadone maintenance programs. These children responded to an extensive 2.5-hour interview questionnaire focusing on current and past activities, including criminal activities prior to age 12. The findings revealed that early deviance, assessed by self-report measures of both severity and variety, is related to current adolescent drug and alcohol use, association with deviant peers, a negative view of home atmosphere, and psychological symptomatology. These results are contrasted with the retrospective reports of adolescent behavior obtained from adult male narcotic addicts in a prior study of vulnerability to addiction. The comparability of study results is discussed in the context of developmental risk factors, prevention and treatment strategies, and other considerations specifically related to the development of children of narcotic addicts. [ABSTRACT FROM AUTHOR]

This survey study of male and female narcotic addicts participating in methadone maintenance programs examined self-reported retrospective data on parental behavior experienced by addicts during their adolescent years. These findings were contrasted with the addicts' self-report of their current parenting practices with their own adolescent children. Results showed addicts as perceiving their mothers as significantly more functional in their parenting practices than their fathers on indices of parental involvement, attachment, and responsibility. Significant parenting differences between addicts and their parents were reported for the three indices mentioned, as well as for parent discipline and punitive actions, with the addicts rating their current parenting practices as more effective than those of their parents. Reported parenting practices were further analyzed in the context of how the ratings of parental functioning were related to problems of drug and alcohol abuse exhibited in the home. Findings are discussed in terms of the implications for prevention and treatment approaches for addicts and their children. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the extrapyramidal symptoms of patients with tardive dyskinesia in Maryland. It aims to determine the relationship of tardive dyskinesia symptoms to the cessation of neuroleptic medication, increase in dosage levels and use of antiparkinson agents. A sample of chronic hospital in-patients at Spring Grove State Hospital in Maryland served as subjects of the study. The patients' medical-psychiatric records were reviewed and conventional neurological examinations and analysis of clinical laboratory records were conducted. Results indicate that symptom severity is lower during neuroleptic treatment. Antiparkinson drugs failed to reduce symptom manifestation and no relationship between symptom severity and dosage was found.

We report an x-ray diffraction study of a HgTe-CdTe superlattice (SL)/HgCdTe heterostructure grown by molecular beam epitaxy (MBE). The diffraction results are used to place an upper bound on the misfit accommodation at the lattice-mismatched SL/HgCdTe interface. The misfit accommodation at the heterointerface is at least an order of magnitude less than that predicted by equilibrium misfit theory. It appears that the low substrate temperature used in MBE HgCdTe growth imposes a kinetic barrier to misfit accommodation. [ABSTRACT FROM AUTHOR]