70 research outputs found

    Identifying a role for WASH in the endocytic pathway of Dictyostelium discoideum

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    Members of the WASP protein family are direct activators of the arp2/3 complex, thereby regulating the nucleation of branched actin assemblies within the cell. Each sub-class possesses a unique N-terminal domain architecture allowing a division of labour between its members, each coupling different signal transduction pathways to the nucleation of specific actin structures. WASH (WASP and SCAR homologue) is a newly identified member of the WASP protein family. Due to its disruption in DrosophilaDrosophila proving lethal (Linardopopoulou et al., 2007) little is know as to the functional role of WASH at the cellular level. Other than it is important in the development of multicellular organisms. Here we successfully disrupt WASH in the single celled amoebae DictyosteliumDictyostelium discoideumdiscoideum and discover a role for WASH in the endocytic pathway. WASH was shown to be essential for the trafficking of indigestible material through the endocytic pathway, with its disruption causing a complete bock in cellular defecation. This was shown to be due to a defect in lysosomal maturation into neutral post-lysosomes. Using fluorescently tagged fusion proteins we show that WASH recruitment coincides with removal of the Vacuolar H+ ATPase from lysosomal membranes, and suggests a possible role for WASH and actin in regulating the luminal pH of intracellular compartments

    The Decline and Absence of Young Adults at Grace Place Christian Church

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    The purpose of the study was to address the problem of low attendance and engagement among young adults at Grace Place Christian Church. This topic is given consideration based on the researcher’s observation of the absence of this demographic within the local ministry context. The literature review revealed this is a common problem throughout the Body of Christ. Grace Place Christian Church is a predominately African American within a military community. The unique characteristics of this ministry context warranted research specific to it. The researcher interviewed twenty unchurched young adults and ten pastors and collected over one hundred nine questionnaires related to the problem. A focus group developed a strategic intervention. The intervention was implemented within the local ministry context. The study revealed hindrances to young adult attendance and participation due to cynicism, a general mistrust of Christians whom they perceive as hypocritical, intolerant, dismissive of intellectual inquiry, and negligent of their perceived responsibility of activism supporting moral progress and social justice. The intervention devised and implemented within this ministry context yielded positive results over a ninety-day evaluation period. Further study is needed to determine if immediate results will hold, increase, or decrease over a more extended evaluation period. The perpetuation of Christianity and the message of Christ is inextricably tied to the church’s ability to transfer leadership from one generation to the next. Thus, the attendance and participation of young adults are critical to sustaining the church

    Initial investigation using statistical process control for quality control of accelerator beam steering

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    <p>Abstract</p> <p>Background</p> <p>This study seeks to increase clinical operational efficiency and accelerator beam consistency by retrospectively investigating the application of statistical process control (SPC) to linear accelerator beam steering parameters to determine the utility of such a methodology in detecting changes prior to equipment failure (interlocks actuated).</p> <p>Methods</p> <p>Steering coil currents (SCC) for the transverse and radial planes are set such that a reproducibly useful photon or electron beam is available. SCC are sampled and stored in the control console computer each day during the morning warm-up. The transverse and radial - positioning and angle SCC for photon beam energies were evaluated using average and range (Xbar-R) process control charts (PCC). The weekly average and range values (subgroup n = 5) for each steering coil were used to develop the PCC. SCC from September 2009 (annual calibration) until two weeks following a beam steering failure in June 2010 were evaluated. PCC limits were calculated using the first twenty subgroups. Appropriate action limits were developed using conventional SPC guidelines.</p> <p>Results</p> <p>PCC high-alarm action limit was set at 6 standard deviations from the mean. A value exceeding this limit would require beam scanning and evaluation by the physicist and engineer. Two low alarms were used to indicate negative trends. Alarms received following establishment of limits (week 20) are indicative of a non-random cause for deviation (Xbar chart) and/or an uncontrolled process (R chart). Transverse angle SCC for 6 MV and 15 MV indicated a high-alarm 90 and 108 days prior to equipment failure respectively. A downward trend in this parameter continued, with high-alarm, until failure. Transverse position and radial angle SCC for 6 and 15 MV indicated low-alarms starting as early as 124 and 116 days prior to failure, respectively.</p> <p>Conclusion</p> <p>Radiotherapy clinical efficiency and accelerator beam consistency may be improved by instituting SPC methods to monitor the beam steering process and detect abnormal changes prior to equipment failure.</p> <p><b>PACS numbers: </b>87.55n, 87.55qr, 87.56bd</p

    Stepwise Conformational Stabilization of a HIV-1 Clade C Consensus Envelope Trimer Immunogen Impacts the Profile of Vaccine-Induced Antibody Responses.

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    Stabilization of the HIV-1 Envelope glycoprotein trimer (Env) in its native pre-fusion closed conformation is regarded as one of several requirements for the induction of neutralizing antibody (nAb) responses, which, in turn, will most likely be a prerequisite for the development of an efficacious preventive vaccine. Here, we systematically analyzed how the stepwise stabilization of a clade C consensus (ConC) Env immunogen impacts biochemical and biophysical protein traits such as antigenicity, thermal stability, structural integrity, and particle size distribution. The increasing degree of conformational rigidification positively correlates with favorable protein characteristics, leading to optimized homogeneity of the protein preparations, increased thermal stability, and an overall favorable binding profile of structure-dependent broadly neutralizing antibodies (bnAbs) and non-neutralizing antibodies (non-nAbs). We confirmed that increasing the structural integrity and stability of the Env trimers positively correlates with the quality of induced antibody responses by the immunogens. These and other data contribute to the selection of ConCv5 KIKO as novel Env immunogens for use within the European Union's H2020 Research Consortium EHVA (European HIV Alliance) for further preclinical analysis and phase 1 clinical development

    Taking Ownership: Our Pledge to Educate All of Detroit's Children

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    Excellent Schools Detroit represents a broad and diverse cross section of Detroit's education, government, civic and community, parent, organized labor, and philanthropic leaders who are committed to ensuring that all Detroit children receive the great education they deserve. This citywide education plan reflects months of discussions and deliberations by coalition members, as well as a series of six community meetings in November and December, youth focus groups, small group discussions with multiple stakeholders, and other outreach efforts. We appreciate the thoughtful recommendations from the many Detroiters who are as passionate as we are about the need to prepare all students for college, careers, and life in the 21st century

    Tropism and neutralisation studies on bat influenza H17N10

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    The diversity of subtypes within Influenza A recently expanded with identification of H17N10 and H18N11 from bats. To study the tropism and zoonotic potential of these viruses, we successfully produced lentiviral pseudotypes bearing haemagglutinin H17 and neuraminidase N10. We investigated a range of cell lines from different species for their susceptibility to infection by these pseudotypes and show that a number of human haematopoietic cancer cell lines and the canine kidney MDCK II (but not MDCK I) cells are susceptible. Using microarrays and qRT-PCR we show that the dog leukocyte antigen DLA-DRA mRNA is over expressed in late passaged parental MDCK and commercial MDCK II cells, compared to early passaged parental MDCK and MDCK I cells, respectively. The human orthologue HLA-DRA encodes the alpha subunit of the MHC class II HLA-DR antigen-binding heterodimer. Small interfering RNA- or neutralizing antibody-targeting HLA-DRA, drastically reduced the susceptibility of Raji B cells to H17-PV. Conversely, over expression of HLA-DRA and its paralogue HLA-DRB1 on the surface of unsusceptible HEK293T/17 cells conferred susceptibility to H17-PV. The identification of HLA-DR as an H17N10 entry mediator will contribute to understanding the tropism of the virus and help to elucidate its zoonotic transmission. We also show that H17 pseudotypes can be efficiently neutralised by the broadly-neutralizing HA2 stalk monoclonal antibodies CR9114 and FI6. The lentiviral pseudotype system is a useful research tool, amenable for investigation of bat influenza tropism, restriction and pandemic preparedness, without safety issues of producing a replication-competent virus, to which the human population is naïve

    From days to decades: short- and long-term variation in environmental conditions affect offspring diet composition of a marine top predator

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    Long-term changes in climate are affecting the abundance, distribution and phenology of species across all trophic levels. Short-term climate variability is also having a profound impact on species and trophic interactions. Crucially, species will experience long- and short-term variation simultaneously, and both are predicted to change, yet studies tend to focus on only one of these temporal scales. Apex predators are sensitive to long-term climate-driven changes in prey populations and short-term effects of weather on prey availability, both of which could result in changes of diet. We investigated temporal trends and effects of long- and short-term environmental variability on chick diet composition in a North Sea population of European shags Phalacrocorax aristotelis between 1985 and 2014. The proportion of their principal prey, lesser sandeel Ammodytes marinus, declined from 0.99 (1985) to 0.51 (2014), and estimated sandeel size declined from 104.5 to 92.0 mm. Concurrently, diet diversification increased from 1.32 (1985) to 11.05 (2014) prey types yr-1, including members of the families Pholidae, Callionymidae and Gadidae. The relative proportion of adult to juvenile sandeel was greater following low sea surface temperatures (SSTs) in the previous year. In contrast, the proportion of Pholidae and prey richness were higher following high SST in the previous year. Within a season, the proportion of sandeel in the diet was lower on days with higher wind speeds. Crucially, our results showed that diet diversification was linked to trends in SST. Thus, predicted changes in climate means and variability may have important implications for diet composition of European shags in the future, with potential consequences for population dynamics

    Developing estimates for the valuation of air pollution removal in ecosystem accounts. Final report for Office of National Statistics

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    Brief summary: This report develops a natural capital account for air pollution removal by vegetation in the UK, over four time periods: 2007, 2011, 2015 and 203

    Seasonality of isoprene emissions and oxidation products above the remote Amazon

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    The Amazon rainforest is the largest source of isoprene emissions to the atmosphere globally. Under low nitric oxide (NO) conditions (i.e. at NO mixing ratios less than about 40 pptv), isoprene reacts rapidly with hydroxyl (OH) to form isoprene-derived peroxy radicals (ISOPOO), which subsequently react with the hydroperoxyl radical (HO2) to form isoprene epoxydiols (IEPOX). IEPOX compounds are efficient precursors to the formation of secondary organic aerosols (SOA). Natural isoprene emissions, therefore, have the potential to influence cloudiness, rainfall, radiation balance and climate. Here, we present the first seasonal analysis of isoprene emissions and concentrations above the Amazon based on eddy covariance flux measurements made at a remote forest location. We reveal the forest to maintain a constant emission potential of isoprene throughout the year (6.9 mg m-2 h-1). The emission potential of isoprene is calculated by normalising the measured fluxes to a set of standard conditions (303 K and 1500 mmol m-2 s-1). During the wet season a factor of two reduction in absolute emissions was observed but this is explained entirely on the basis of meteorology and leaf area index, not by a change in isoprene emissions potential. Using an innovative analysis of the isoprene fluxes, in combination with measurements of its oxidation products and detailed chemical box-modelling, we explore whether concentrations of IEPOX follow the same seasonal cycle as the isoprene precursor. Our analysis implies that during the dry season (Sep–Jan) air pollution from regional biomass burning provides a modest increase in NO concentrations (indirectly inferred from a combination of other anthropogenic tracer measurements and box-modelling) which creates a competing oxidation pathway for ISOPOO; rather than forming IEPOX, alternative products are formed with less propensity to produce aerosol. This competition decreases IEPOX formation rates by a factor of two in the dry season compared with a scenario with no anthropogenic NO pollution, and by 30% throughout the year. The abundance of biogenic SOA precursors in the Amazon appears not to be dictated by the seasonality of natural isoprene emissions as previously thought, but is instead driven by regional anthropogenic pollution which modifies the atmospheric chemistry of isoprene
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