31 research outputs found
Enhancing volunteer engagement to achieve desirable outcomes: what can non-profit employers do?
Abstract Engagement is a positive psychological state that is linked with a range of beneficial individual and organizational outcomes. However, the factors associated with volunteer engagement have rarely been examined. Data from 1064 volunteers of a wildlife charity in the United Kingdom revealed that both task- and emotion-oriented
organizational support were positively related to volunteer engagement, and volunteer engagement was positively related to volunteer happiness and perceived social worth and negatively related to intent to leave the voluntary organization.
Consistent with theory, engagement acted as a mediator between these factors. The implications for future research and the relevance of the findings for voluntary organizations are discussed
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Myosin Vs organize actin cables in fission yeast.
Myosin V motors are believed to contribute to cell polarization by carrying cargoes along actin tracks. In Schizosaccharomyces pombe, Myosin Vs transport secretory vesicles along actin cables, which are dynamic actin bundles assembled by the formin For3 at cell poles. How these flexible structures are able to extend longitudinally in the cell through the dense cytoplasm is unknown. Here we show that in myosin V (myo52 myo51) null cells, actin cables are curled, bundled, and fail to extend into the cell interior. They also exhibit reduced retrograde flow, suggesting that formin-mediated actin assembly is impaired. Myo52 may contribute to actin cable organization by delivering actin regulators to cell poles, as myoV defects are partially suppressed by diverting cargoes toward cell tips onto microtubules with a kinesin 7-Myo52 tail chimera. In addition, Myo52 motor activity may pull on cables to provide the tension necessary for their extension and efficient assembly, as artificially tethering actin cables to the nuclear envelope via a Myo52 motor domain restores actin cable extension and retrograde flow in myoV mutants. Together these in vivo data reveal elements of a self-organizing system in which the motors shape their own tracks by transporting cargoes and exerting physical pulling forces
Identification of human glycosyltransferase genes expressed in erythroid cells predicts potential carbohydrate blood group loci
Glycans are biologically important structures synthesised by glycosyltransferase (GT) enzymes. Disruptive genetic null variants in GT genes can lead to serious illness but benign phenotypes are also seen, including antigenic differences on the red blood cell (RBC) surface, giving rise to blood groups. To characterise known and potential carbohydrate blood group antigens without a known underlying gene, we searched public databases for human GT loci and investigated their variation in the 1000 Genomes Project (1000 G). We found 244 GT genes, distributed over 44 families. All but four GT genes had missense variants or other variants predicted to alter the amino acid sequence, and 149 GT genes (61%) had variants expected to cause null alleles, often associated with antigen-negative blood group phenotypes. In RNA-Seq data generated from erythroid cells, 155 GT genes were expressed at a transcript level comparable to, or higher than, known carbohydrate blood group loci. Filtering for GT genes predicted to cause a benign phenotype, a set of 30 genes remained, 16 of which had variants in 1000 G expected to result in null alleles. Our results identify potential blood group loci and could serve as a basis for characterisation of the genetic background underlying carbohydrate RBC antigens