Use of ERTS-1 data to access and monitor change in the west side of the San Joaquin Valley and central coastal zone of California

There are no author-identified significant results in this report

A Compact Ring for Thom X-Ray Source

International audienceThe goal of X-ray sources based on Compton back scattering processes is to develop a compact device, which could produce an intense flux of monochromatic X-rays. Compton back-scattering resuls from collisions between laser pulses and relativistic electron bunches. Due to the relative low value of the Compton cross section, a high charge electron beam, a low emittance and a high focusing at the interaction point are required for the electron beam. In addition, the X-ray flux is related to the characteristics of the electron beam, which are themselves dynamically affected by the Compton interaction. One possible configuration is to inject frequently into a storage ring with a low emittance linear accelerator without waiting for the synchrotron equilibrium. As a consequence, the optics should be designed taking into account the characteristics of the electron beam from the linear accelerator. The accelerator ring design for a 50 MeV electron beam, aiming at producing a flux higher than 1013 ph/s, will be presented

Frequencies of polymorphisms associated with BSE resistance differ significantly between Bos taurus, Bos indicus, and composite cattle

<p>Abstract</p> <p>Background</p> <p>Transmissible spongiform encephalopathies (TSEs) are neurodegenerative diseases that affect several mammalian species. At least three factors related to the host prion protein are known to modulate susceptibility or resistance to a TSE: amino acid sequence, atypical number of octapeptide repeats, and expression level. These factors have been extensively studied in breeds of <it>Bos taurus </it>cattle in relation to classical bovine spongiform encephalopathy (BSE). However, little is currently known about these factors in <it>Bos indicus </it>purebred or <it>B. indicus </it>× <it>B. taurus </it>composite cattle. The goal of our study was to establish the frequency of markers associated with enhanced susceptibility or resistance to classical BSE in <it>B. indicus </it>purebred and composite cattle.</p> <p>Results</p> <p>No novel or TSE-associated <it>PRNP</it>-encoded amino acid polymorphisms were observed for <it>B. indicus </it>purebred and composite cattle, and all had the typical number of octapeptide repeats. However, differences were observed in the frequencies of the 23-bp and 12-bp insertion/deletion (indel) polymorphisms associated with two bovine <it>PRNP </it>transcription regulatory sites. Compared to <it>B. taurus</it>, <it>B. indicus </it>purebred and composite cattle had a significantly lower frequency of 23-bp insertion alleles and homozygous genotypes. Conversely, <it>B. indicus </it>purebred cattle had a significantly higher frequency of 12-bp insertion alleles and homozygous genotypes in relation to both <it>B. taurus </it>and composite cattle. The origin of these disparities can be attributed to a significantly different haplotype structure within each species.</p> <p>Conclusion</p> <p>The frequencies of the 23-bp and 12-bp indels were significantly different between <it>B. indicus </it>and <it>B. taurus </it>cattle. No other known or potential risk factors were detected for the <it>B. indicus </it>purebred and composite cattle. To date, no consensus exists regarding which bovine <it>PRNP </it>indel region is more influential with respect to classical BSE. Should one particular indel region and associated genotypes prove more influential with respect to the incidence of classical BSE, differences regarding overall susceptibility and resistance for <it>B. indicus </it>and <it>B. taurus </it>cattle may be elucidated.</p

Positive youth development in swimming: clarification and consensus of key psychosocial assets

The purpose of this study was to gain a more cohesive understanding of the assets considered necessary to develop in young swimmers to ensure both individual and sport specific development. This two stage study involved (a) a content analysis of key papers to develop a list of both psychosocial skills for performance enhancement and assets associated with positive youth development, and (b) in-depth interviews involving ten expert swim coaches, practitioners and youth sport scholars. Five higher order categories containing seventeen individual assets emerged. These results are discussed in relation to both existing models of positive youth development and implications for coaches, practitioners and parents when considering the psychosocial development of young British swimmers

Evaluation of PRNP Expression Based on Genotypes and Alleles of Two Indel Loci in the Medulla Oblongata of Japanese Black and Japanese Brown Cattle

BACKGROUND: Prion protein (PrP) level plays the central role in bovine spongiform encephalopathy (BSE) susceptibility. Increasing the level of PrP decreases incubation period for this disease. Therefore, studying the expression of the cellular PrP or at least the messenger RNA might be used in selection for preventing the propagation of BSE and other prion diseases. Two insertion/deletion (indel) variations have been tentatively associated with susceptibility/resistance of cattle to classical BSE. METHODOLOGY/PRINCIPAL FINDINGS: We studied the expression of each genotype at the two indel sites in Japanese Black (JB) and Japanese Brown (JBr) cattle breeds by a standard curve method of real-time PCR. Five diplotypes subdivided into two categories were selected from each breed. The two cattle breeds were considered differently. Expression of PRNP was significantly (p<0.0001) greater in the homozygous deletion genotype at the 23-bp locus in JB breed. Compared to the homozygous genotypes, the expression of PRNP was significantly greater in the heterozygous genotype at the 12-bp locus in JB (p<0.0001) and in JBr (p = 0.0394) breeds. In addition, there was a statistical significance in the PRNP levels between the insertion and the deletion alleles of the 23-bp locus in JB (p = 0.0003) as well as in JBr (p = 0.0032). There was no significance in relation to sex, age, geographical location or due to their interactions (p>0.05). CONCLUSION: Our results suggest that the del/del genotype or at least its del allele may modulate the expression of PRNP at the 23-bp locus in the medulla oblongata of these cattle breeds

Nucleotide and phylogenetic analyses of the Chlamydia trachomatis ompA gene indicates it is a hotspot for mutation

<p>Abstract</p> <p>Background</p> <p>Serovars of the human pathogen <it>Chlamydia trachomatis </it>occupy one of three specific tissue niches. Genomic analyses indicate that the serovars have a phylogeny congruent with their pathobiology and have an average substitution rate of less than one nucleotide per kilobase. In contrast, the gene that determines serovar specificity, <it>ompA</it>, has a phylogenetic association that is not congruent with tissue tropism and has a degree of nucleotide variability much higher than other genomic loci. The <it>ompA </it>gene encodes the major surface-exposed antigenic determinant, and the observed nucleotide diversity at the <it>ompA </it>locus is thought to be due to recombination and host immune selection pressure. The possible contribution of a localized increase in mutation rate, however, has not been investigated.</p> <p>Results</p> <p>Nucleotide diversity and phylogenetic relationships of the five constant and four variable domains of the <it>ompA </it>gene, as well as several loci surrounding <it>ompA</it>, were examined for each serovar. The loci flanking the <it>ompA </it>gene demonstrated that nucleotide diversity increased monotonically as <it>ompA </it>is approached and that their gene trees are not congruent with either <it>ompA </it>or tissue tropism. The variable domains of the <it>ompA </it>gene had a very high level of non-synonymous change, which is expected as these regions encode the surface-exposed epitopes and are under positive selection. However, the synonymous changes are clustered in the variable regions compared to the constant domains; if hitchhiking were to account for the increase in synonymous changes, these substitutions should be more evenly distributed across the gene. Recombination also cannot entirely account for this increase as the phylogenetic relationships of the constant and variable domains are congruent with each other.</p> <p>Conclusions</p> <p>The high number of synonymous substitutions observed within the variable domains of <it>ompA </it>appears to be due to an increased mutation rate within this region of the genome, whereas the increase in nucleotide substitution rate and the lack of phylogenetic congruence in the regions flanking <it>ompA </it>are characteristic motifs of gene conversion. Together, the increased mutation rate in the <it>ompA </it>gene, in conjunction with gene conversion and positive selection, results in a high degree of variability that promotes host immune evasion.</p

Adaptive capacity in social–ecological systems: a framework for addressing bark beetle disturbances in natural resource management

The ability of natural resource agencies to act before, during, and after outbreaks of conifer bark beetles (Coleoptera: Curculionidae) is important to ensure the continued provision of ecosystem services. Adaptive capacity refers to the capability of an agent or system to adapt to change, regardless of whether it is examined as an independent social or ecological entity, or as a coupled social–ecological system. Understanding the components of a disturbance and the associated effects to ecosystem services, social systems, and natural resource management increases the ability to adapt to change and ensure continued resilience. This paper presents a definition and conceptual framework of adaptive capacity relevant to bark beetle disturbances that was developed through an interdisciplinary workshop held in 2016. The intent is to assist natural resource managers and policy-makers in identifying important adaptation characteristics to effectively address bark beetle disturbances. The current state of knowledge regarding institutional, social, and environmental factors that influence adaptive capacity are identified. The mountain pine beetle (Dendroctonus ponderosae) in the western USA is used as a specific example to discuss several factors that influence adaptive capacity for increasing resilience. We hope that our proposed framework serves as a model for future collaborations among both social and physical scientists and land managers to better address landscape-level disturbances that are being exacerbated by climate change

Psychosocial risk factors for suicidality in children and adolescents

Suicidality in childhood and adolescence is of increasing concern. The aim of this paper was to review the published literature identifying key psychosocial risk factors for suicidality in the paediatric population. A systematic two-step search was carried out following the PRISMA statement guidelines, using the terms ‘suicidality, suicide, and self-harm’ combined with terms ‘infant, child, adolescent’ according to the US National Library of Medicine and the National Institutes of Health classification of ages. Forty-four studies were included in the qualitative synthesis. The review identified three main factors that appear to increase the risk of suicidality: psychological factors (depression, anxiety, previous suicide attempt, drug and alcohol use, and other comorbid psychiatric disorders); stressful life events (family problems and peer conflicts); and personality traits (such as neuroticism and impulsivity). The evidence highlights the complexity of suicidality and points towards an interaction of factors contributing to suicidal behaviour. More information is needed to understand the complex relationship between risk factors for suicidality. Prospective studies with adequate sample sizes are needed to investigate these multiple variables of risk concurrently and over time

Development and psychometric properties of the “Suicidality: Treatment Occurring in Paediatrics (STOP) Risk and Resilience Factors Scales” in adolescents

Suicidality in the child and adolescent population is a major public health concern. There is, however, a lack of developmentally sensitive valid and reliable instruments that can capture data on risk, and clinical and psychosocial mediators of suicidality in young people. In this study, we aimed to develop and assess the validity of instruments evaluating the psychosocial risk and protective factors for suicidal behaviours in the adolescent population. In Phase 1, based on a systematic literature review of suicidality, focus groups, and expert panel advice, the risk factors and protective factors (resilience factors) were identified and the adolescent, parent, and clinician versions of the STOP-Suicidality Risk Factors Scale (STOP-SRiFS) and the Resilience Factors Scale (STOP-SReFS) were developed. Phase 2 involved instrument validation and comprised of two samples (Sample 1 and 2). Sample 1 consisted of 87 adolescents, their parents/carers, and clinicians from the various participating centres, and Sample 2 consisted of three sub-samples: adolescents (n = 259) who completed STOP-SRiFS and/or the STOP-SReFS scales, parents (n = 213) who completed one or both of the scales, and the clinicians who completed the scales (n = 254). The STOP-SRiFS demonstrated a good construct validity—the Cronbach Alpha for the adolescent (α = 0.864), parent (α = 0.842), and clinician (α = 0.722) versions of the scale. Test–retest reliability, inter-rater reliability, and content validity were good for all three versions of the STOP-SRiFS. The sub-scales generated using Exploratory Factor Analysis (EFA) were the (1) anxiety and depression risk, (2) substance misuse risk, (3) interpersonal risk, (4) chronic risk, and (5) risk due to life events. For the STOP-SRiFS, statistically significant correlations were found between the Columbia-Suicide Severity Rating Scale (C-SSRS) total score and the adolescent, parent, and clinical versions of the STOP-SRiFS sub-scale scores. The STOP-SRiFS showed good psychometric properties. This study demonstrated a good construct validity for the STOP-SReFS—the Cronbach Alpha for the three versions were good (adolescent: α = 0.775; parent: α = 0.808; α = clinician: 0.808). EFA for the adolescent version of the STOP-SReFS, which consists of 9 resilience factors domains, generated two factors (1) interpersonal resilience and (2) cognitive resilience. The STOP-SReFS Cognitive Resilience sub-scale for the adolescent was negatively correlated (r = −&nbsp;0.275) with the C-SSRS total score, showing that there was lower suicidality in those with greater Cognitive Resilience. The STOP-SReFS Interpersonal resilience sub-scale correlations were all negative, but none of them were significantly different to the C-SSRS total scores for either the adolescent, parent, or clinician versions of the scales. This is not surprising, because the items in this sub-scale capture a much larger time-scale, compared to the C-SSRS rating period. The STOP-SReFS showed good psychometric properties. The STOP-SRiFS and STOP-SReFS are instruments that can be used in future studies about suicidality in children and adolescents