Temporary streams in temperate zones: recognizing, monitoring and restoring transitional aquatic-terrestrial ecosystems

Temporary streams are defined by periodic flow cessation, and may experience partial or complete loss of surface water. The ecology and hydrology of these transitional aquatic-terrestrial ecosystems have received unprecedented attention in recent years. Research has focussed on the arid, semi-arid, and Mediterranean regions in which temporary systems are the dominant stream type, and those in cooler, wetter temperate regions with an oceanic climate influence are also receiving increasing attention. These oceanic systems take diverse forms, including meandering alluvial plain rivers, ‘winterbourne’ chalk streams, and peatland gullies. Temporary streams provide ecosystem services and support a diverse biota that includes rare and endemic specialists. We examine this biota and illustrate that temporary stream diversity can be higher than in comparable perennial systems, in particular when differences among sites and times are considered; these diversity patterns can be related to transitions between lotic, lentic, and terrestrial instream conditions. Human impacts on temperate-zone temporary streams are ubiquitous, and result from water-resource and land-use-related stressors, which interact in a changing climate to alter natural flow regimes. These impacts may remain uncharacterized due to inadequate protection of small temporary streams by current legislation, and hydrological and biological monitoring programs therefore require expansion to better represent temporary systems. Novel, temporary-stream-specific biomonitors and multi-metric indices require development, to integrate characterization of ecological quality during lotic, lentic, and terrestrial phases. In addition, projects to restore flow regimes, habitats, and communities may be required to improve the ecological quality of temporary stream

Adolescents with sexually inappropriate behaviours : background, characteristics and approaches to intervention

The incidence of sexually inappropriate behaviour in adolescents is increasing. Understanding of the nature, incidence and characteristics of the perpetrators of such behaviours is growing; however a validated and conclusive aetiology of sexually inappropriate behaviour in adolescents remains elusive. A specialist project for adolescents with sexually inappropriate behaviours was accessed as a component of a national evaluation project, from where the research developed. It was the first aim of the research to explore the characteristics of a British sample of adolescents with sexually inappropriate behaviours attending a specialised intervention project. A retrospective analysis of case file records of young people was undertaken. A number of characteristics common to previous research were found as were a number contrary. A number of differences were observed between young people convicted and those alleged to have committed sexually inappropriate acts. Intervention for adolescent offenders has seen considerable growth. However, offending continues and adolescents continue to re-offend despite receiving intervention. As a consequence, the second and third aims of the research were to psychometrically assess a sample of adolescents with sexually inappropriate behaviours. The validity of a proposed model of sexually inappropriate behaviour was tested and the efficacy of a specialist intervention project was assessed. Sexually inappropriate young people, non-sexual offenders and non-offenders were comparatively assessed. A small number of statistically significant xi differences were found between the groups. However there were no statistically significant differences found in the majority of assessed areas. The adolescents who participated in the research were a heterogeneous group with differing characteristics and needs. No support was found for the tested model of sexually inappropriate behaviours in adolescents. Comparative analyses of the score results compared at two points in time showed no significant differences in scores after intervention by the specialist intervention project. Research has also acknowledged the need to look beyond the content of offending intervention to how it is delivered. Psychological therapy research has recognised the role and importance of the working alliance between a professional and patient and the concept has began to be explored within research and intervention with adult sexual offenders. The role of the working alliance within youth offending research has received limited research attention. Therefore it was the last aim of the research to explore the concept of a working alliance in youth offending intervention and its impact on successful outcomes. Interviews were conducted with youth offending professionals and young offenders and grounded theory analyses were completed to produce a model of interpretations of the role of the working alliance. The findings suggest that a working alliance exerts some influence on the success of youth offending interventions

Behavioural features of cerebral visual impairment are common in children with down syndrome

It is widely recognised that children with Down syndrome have a broad range and a high prevalence of visual deficits and it has been suggested that those with Down syndrome are more likely to exhibit visual perception deficits indicative of cerebral visual impairment. This exploratory study aims to determine the prevalence of behavioural features suggestive of cerebral visual impairment (CVI) occurring with Down syndrome and whether the visual problems can be ascribed to optometric factors. A cohort of 226 families of children with Down syndrome (trisomy 21), aged 4–17, were invited to participate in a validated question inventory, to recognise visual perception issues. The clinical records of the participants were then reviewed retrospectively. A five-question screening instrument was used to indicate suspected CVI. The majority of the 81 families who responded to the questionnaire reported some level of visual perceptual difficulty in their child. Among this cohort, the prevalence of suspected CVI as indicated by the screening questionnaire was 38%. Only ametropia was found to have a significant association with suspected CVI, although this increased the correct prediction of suspected CVI outcome by only a small amount. Results suggest that children with Down syndrome are more likely to experience problems consistent with cerebral visual impairment, and that these may originate from a similar brain dysfunction to that which contributes to high levels of ametropia and failure to emmetropise. It is important that behavioural features of CVI are recognised in children with Down syndrome, further investigations initiated and appropriate management applied.V. Vinuela-Navarro and R. England were funded by Action Medical Research for Children GN2338.Peer ReviewedPostprint (author's final draft

Evolutionary causes and consequences of diversified CRISPR immune profiles in natural populations

Abstract Host-pathogen co-evolution is a significant force which shapes the ecology and evolution of all types of organisms, and such interactions are driven by resistance and immunity mechanisms of the host. Diversity of resistance and immunity can affect the co-evolutionary trajectory of both host and pathogen. The microbial CRISPR (clustered regularly interspaced short palindromic repeats)-Cas (CRISPR-associated) system is one host immunity mechanism which offers a tractable model for examining the dynamics of diversity in an immune system. In the present article, we review CRISPR variation observed in a variety of natural populations, examine the forces which can push CRISPRs towards high or low diversity, and investigate the consequences of various levels of diversity on microbial populations

Ultrasonography of the prostate gland and testes in dogs

Ultrasonographic imaging is an important diagnostic tool because it allows assessment of the shape, size, position, margination and internal architecture of organs, as well as facilitating the study of vascular supply and vascularisation. Recently, there has been considerable development of B-mode, Doppler and contrast-enhanced ultrasonography for examination of the reproductive tract of dogs, both for studying normal physiology and in the clinical setting. This article describes the practical examination of the canine prostate gland and testes using a variety of ultrasound techniques, and details the normal appearance and blood flow of these organs as well as changes that may be observed with common reproductive disorders

Prevalence of ultrasound-determined cystic endometrial hyperplasia and the relationship with age in dogs

To investigate the potential relationship between age and diagnosis of cystic endometrial hyperplasia (CEH) in the bitches, 348 ultrasound examinations from 240 bitches (Labradors, Golden Retrievers, German Shepherds, Flat Coated Retrievers, or crosses of those breeds aged between 1.6 and 7.2 years at examination) were examined. A subpopulation of 32 bitches that had completed their breeding careers at 6 years or more of age was also identified. Of all, 18.3% of the bitches were diagnosed with CEH; these cases were newly diagnosed when bitches were between 2.5 years and 7.3 years of age. The proportion of ultrasound examinations in which CEH was identified increased from 6.8% of examinations on 2-year-old breeding bitches to 60.0% of examinations on 6-year-old bitches. Logistic regression identified a positive correlation between mean age at the examination and presence of CEH (χ2 = 30.74, degrees of freedom = 1, P < 0.001). For 32 bitches that had completed their breeding career, the prevalence of CEH was 56.3%, age at the diagnosis ranged from 3.8 to 7.3 years, and the proportion of bitches affected with CEH increased from 6.3% at 3 years of age to 56.3% at 7 years of age. These data support the contention that the prevalence of CEH increases with age