766 research outputs found
Hinge for Use in a Tension Stiffened and Tendon Actuated Manipulator
A tension stiffened and tendon actuated manipulator is provided performing robotic-like movements when acquiring a payload. The manipulator design can be adapted for use in-space, lunar or other planetary installations as it is readily configurable for acquiring and precisely manipulating a payload in both a zero-g environment and in an environment with a gravity field. The manipulator includes a plurality of link arms, a hinge connecting adjacent link arms together to allow the adjacent link arms to rotate relative to each other and a cable actuation and tensioning system provided between adjacent link arms. The cable actuation and tensioning system includes a spreader arm and a plurality of driven and non-driven elements attached to the link arms and the spreader arm. At least one cable is routed around the driven and non-driven elements for actuating the hinge
A powerful intervention: general practitioners' use of sickness certification in depression
<b>Background</b> Depression is frequently cited as the reason for sickness absence, and it is estimated that sickness certificates are issued in one third of consultations for depression. Previous research has considered GP views of sickness certification but not specifically in relation to depression. This study aimed to explore GPs views of sickness certification in relation to depression.<p></p>
<b>Methods</b> A purposive sample of GP practices across Scotland was selected to reflect variations in levels of incapacity claimants and antidepressant prescribing. Qualitative interviews were carried out between 2008 and 2009.<p></p>
<b>Results</b> A total of 30 GPs were interviewed. A number of common themes emerged including the perceived importance of GP advocacy on behalf of their patients, the tensions between stakeholders involved in the sickness certification system, the need to respond flexibly to patients who present with depression and the therapeutic nature of time away from work as well as the benefits of work. GPs reported that most patients with depression returned to work after a short period of absence and that it was often difficult to predict which patients would struggle to return to work.<p></p>
<b>Conclusions</b>
GPs reported that dealing with sickness certification and depression presents distinct challenges. Sickness certificates are often viewed as powerful interventions, the effectiveness of time away from work for those with depression should be subject to robust enquiry
Extragenic suppressor mutations in ΔripA disrupt stability and function of LpxA
Abstract
Background
Francisella tularensis is a Gram-negative bacterium that infects hundreds of species including humans, and has evolved to grow efficiently within a plethora of cell types. RipA is a conserved membrane protein of F. tularensis, which is required for growth inside host cells. As a means to determine RipA function we isolated and mapped independent extragenic suppressor mutants in ∆ripA that restored growth in host cells. Each suppressor mutation mapped to one of two essential genes, lpxA or glmU, which are involved in lipid A synthesis. We repaired the suppressor mutation in lpxA (S102, LpxA T36N) and the mutation in glmU (S103, GlmU E57D), and demonstrated that each mutation was responsible for the suppressor phenotype in their respective strains. We hypothesize that the mutation in S102 altered the stability of LpxA, which can provide a clue to RipA function. LpxA is an UDP-N-acetylglucosamine acyltransferase that catalyzes the transfer of an acyl chain from acyl carrier protein (ACP) to UDP-N-acetylglucosamine (UDP-GlcNAc) to begin lipid A synthesis.
Results
LpxA was more abundant in the presence of RipA. Induced expression of lpxA in the ΔripA strain stopped bacterial division. The LpxA T36N S102 protein was less stable and therefore less abundant than wild type LpxA protein.
Conclusion
These data suggest RipA functions to modulate lipid A synthesis in F. tularensis as a way to adapt to the host cell environment by interacting with LpxA.http://deepblue.lib.umich.edu/bitstream/2027.42/110509/1/12866_2014_Article_336.pd
Stigma and GPs’ perceptions of dementia
YesObjectives: General practitioners (GPs) are crucial to improving timely diagnosis, but little is reported about how they
perceive dementia, and whether their perceptions display any elements of stigma. The aim of this study was to explore how
GPs’ perceptions of dementia map onto current conceptualizations of stigma and whether GPs feel that stigma affects
timely diagnosis.
Methods: Twenty-three GPs from England were interviewed by telephone. Data were analyzed by means of content
analysis. This involved open coding followed by the application of a coding framework derived from the literature to
explore how and to what extent their perceptions relate to stigma as well as the unique nature of their perceptions.
Results: Three themes emerged from the analysis: (1) ‘making sense of dementia’, (2) ‘relating perceptions of dementia to
oneself’ and (3) ‘considering the consequences of dementia’. GPs’ perceptions of dementia mapped onto current
conceptualizations of stigma. Perceptions about dementia that were linked to their own existential anxiety and to a
perceived similarity between people with dementia and themselves were particularly salient. GPs perceived dementia as a
stigma which was gradually being overcome but that stigma still hindered timely diagnosis. They provided examples of
structural discrimination within the health service, including lack of time for patients and shortcomings in training that
were to the detriment of people with dementia.
Conclusion: Measures to involve GPs in tackling stigma should include training and opportunities to explore how they
perceive dementia, as well as support to address structural discrimination.The study was funded by Alzheimer Europe (Luxembourg) in the form of tuition fees for Dianne Gove for her PhD study
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
Am I just not good enough? The creation, development and questioning of a high performance coaching identity
While the career experiences and trajectories of various sports workers have received increased scholarly attention, those of professional coaches have, in comparison, received scant consideration. This paper focuses on the career experiences of Maeve (a pseudonym), a high performance coach, and the critical incidents related to the creation, development, and, ultimately, questioning of her professional identity. Data were collected through a series of narrative-biographical interviews and were subject to a process of iterative data analysis. The results indicated that her significant investment into her coaching self, combined with the vagaries and uncertain nature of work in high performance coaching, led her to experience a biographical disruption that interrupted the narrative coherence of her coaching life. The findings add further credence to recent critiques of only understanding and representing coaching careers in a linear and chronically staged fashion
Coordinated evolution of co-expressed gene clusters in the Drosophila transcriptome
Abstract Background Co-expression of genes that physically cluster together is a common characteristic of eukaryotic transcriptomes. This organization of transcriptomes suggests that coordinated evolution of gene expression for clustered genes may also be common. Clusters where expression evolution of each gene is not independent of their neighbors are important units for understanding transcriptome evolution. Results We used a common microarray platform to measure gene expression in seven closely related species in the Drosophila melanogaster subgroup, accounting for confounding effects of sequence divergence. To summarize the correlation structure among genes in a chromosomal region, we analyzed the fraction of variation along the first principal component of the correlation matrix. We analyzed the correlation for blocks of consecutive genes to assess patterns of correlation that may be manifest at different scales of coordinated expression. We find that expression of physically clustered genes does evolve in a coordinated manner in many locations throughout the genome. Our analysis shows that relatively few of these clusters are near heterochromatin regions and that these clusters tend to be over-dispersed relative to the rest of the genome. This suggests that these clusters are not the byproduct of local gene clustering. We also analyzed the pattern of co-expression among neighboring genes within a single Drosophila species: D. simulans. For the co-expression clusters identified within this species, we find an under-representation of genes displaying a signature of recurrent adaptive amino acid evolution consistent with previous findings. However, clusters displaying co-evolution of expression among species are enriched for adaptively evolving genes. This finding points to a tie between adaptive sequence evolution and evolution of the transcriptome. Conclusion Our results demonstrate that co-evolution of expression in gene clusters is relatively common among species in the D. melanogaster subgroup. We consider the possibility that local regulation of expression in gene clusters may drive the connection between adaptive sequence and coordinated gene expression evolution
Next-Generation Mapping of Complex Traits with Phenotype-Based Selection and Introgression
Finding the genes underlying complex traits is difficult. We show that new sequencing technology combined with traditional genetic techniques can efficiently identify genetic regions underlying a complex and quantitative behavioral trait. As a proof of concept we used phenotype-based introgression to backcross loci that control innate food preference in Drosophila simulans into the genomic background of D. sechellia, which expresses the opposite preference. We successfully mapped D. simulans introgression regions in a small mapping population (30 flies) with whole-genome resequencing using light coverage (∼1×). We found six loci contributing to D. simulans food preference, one of which overlaps a previously discovered allele. This approach is applicable to many systems, does not rely on laborious marker development or genotyping, does not require existing high quality reference genomes, and needs only small mapping populations. Because introgression is used, researchers can scale mapping population size, replication, and number of backcross generations to their needs. Finally, in contrast to more widely used mapping techniques like F2 bulk-segregant analysis, our method produces near-isogenic lines that can be kept and reused indefinitely
Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas
This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing
molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin
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