Three Concurrent Phases of Massive-Star Evolution in a Pulsar-Wind Nebula

The nebular material associated the the SNR G54.1+0.3 (hereafter G54) contains the the first reported instance of triggered star formation in the immediate vicinity of a Pulsar and its Wind Nebula (PWN). With 2MASS and Spitzer colors and followup near-IR spectroscopy, we have discovered the presence of a hot, massive and most likely evolved Be-type star among the cluster of stars hosted by the pulsar. This star has probably triggered cloud collapse and formation of at least 11 YSOs, which ring the nebula. In this unique cluster are now identified three concurrent stages of stellar evolution, from massive star birth, post-Main-Sequence transition, and stellar death

Antioxidants Boost Male Fertility: The Role of Reactive Oxygen Species (ROS) in Modulating Fertility and Sperm Viability in Drosophila melanogaster

Reactive oxygen species (ROS) in large amounts have been shown to cause peroxidative damage to tissues. ROS production is heightened in stressful environments, such as after exposure to toxins. Antioxidants have been previously found to reduce lifespan-related, peroxidative damage, inflicted by reactive oxygen species in the common fruit fly (D. melanogaster). Our study analyzes the effects of antioxidants in reducing the damaging effects of reactive oxygen species to rescue pre and post-copulatory reproductive efforts in Drosophila melanogaster. We hypothesized that if male fruit flies were fed antioxidant-enriched diets prior to a reactive oxygen species assault, then the antioxidants would quench the reactive oxygen species. This would then reduce the lipid peroxidation damage to male sperm, resulting in increased pre-copula and post-copula reproductive efforts. Two groups of fruit fly food were each infused with antioxidants, lipoic acid (2.15mM) or melatonin (0.43mM) in 75%ethanol. 75% ethanol solution was used as a control. Males from all treatments were then fed an herbicide, paraquat, to shock their immune systems and increase ROS production. All males were then mated to virgin females and copula behavior, sperm viability and male fertility were assessed. Our results showed significant differences between treatments in sperm viability and number of offspring sired. However, there were no significant differences in mating probability or copula duration (both related to pre-copula sexual selection). These results draw light on the important interplay of ROS and antioxidants in the maintenance of reproductive health especially during stress

Cross-school ‘close-to-practice’ action research, system leadership and local civic-partnership re-engineering an inner-city learning community

This article presents two sequential case reports of how sixty schools in the London borough of Camden used action research in three phases of development of their local school system reform from a traditional Council-led, top down model of centrally based professional development and monitoring of schools, to one that is schools-led and ‘bottom-up’ in nature, but still in close partnership with its local council and community. The article uses a sociocultural lens through which to view this journey of self-reform tracking change through three evolutions of the sociocultural model as professional learning becomes situated in classrooms and between schools in Camden, as motivations to develop and change become increasingly intrinsic and less driven by fear of failure or the consequences of failure. Of critical importance is the feedback-rich context created by adoption of enquiry and coaching-based learning models at classroom, organisational and system levels. This both fuels and is fuelled by the strategic collaboration of headteachers and by system leadership also provided by middle leaders, whose increased cross-school agency builds improvement capacity and collaborative capital. But the article does not report on the action research alone. Unlike many accounts of action research for change, this account provides a narrative backdrop in which to locate both scientific and system developments. This is provided through three short vignettes which place the changes reported in a societal, political and community context without whose energetic actors (in the form of local political and community leaders and school governors) the local ‘civic governance’ so strongly behind these reforms, would not have existed.London Schools Excellence Fund (Greater London Authority

Ultrafast protein response in the Pfr state of Cph1 phytochrome

Photoisomerization is a fundamental process in several classes of photoreceptors. Phytochromes sense red and far-red light in their Pr and Pfr states, respectively. Upon light absorption, these states react via individual photoreactions to the other state. Cph1 phytochrome shows a photoisomerization of its phycocyanobilin (PCB) chromophore in the Pfr state with a time constant of 0.7 ps. The dynamics of the PCB chromophore has been described, but whether or not the apoprotein exhibits an ultrafast response too, is not known. Here, we compare the photoreaction of 13C/15N labeled apoprotein with unlabeled apoprotein to unravel ultrafast apoprotein dynamics in Cph1. In the spectral range from 1750 to 1620 cm−1 we assigned several signals due to ultrafast apoprotein dynamics. A bleaching signal at 1724 cm−1 is tentatively assigned to deprotonation of a carboxylic acid, probably Asp207, and signals around 1670 cm−1 are assigned to amide I vibrations of the capping helix close to the chromophore. These signals remain after photoisomerization. The apoprotein dynamics appear upon photoexcitation or concomitant with chromophore isomerization. Thus, apoprotein dynamics occur prior to and after photoisomerization on an ultrafast time-scale. We discuss the origin of the ultrafast apoprotein response with the ‘Coulomb hammer’ mechanism, i.e. an impulsive change of electric field and Coulombic force around the chromophore upon excitation

Development of Asymmetic Deacylative Allylation

Herein we present the development of asymmetric deacylative allylation of ketone enolates. The reaction directly couples readily available ketone pronucleophiles with allylic alcohols using facile retro-Claisen cleavage to form reactive intermediates in situ. The simplicity and robustness of the reaction conditions is demonstrated by the preparation of > 6 grams of an allylated tetralone from commercially available materials. Furthermore, use of non-racemic PHOX ligands allows intermolecular formation of quaternary stereocenters directly from allylic alcohols

Photocatalytic Aminodecarboxylation of Carboxylic Acids

Aminodecarboxylation of unactivated alkyl carboxylic acids has been accomplished utilizing an organic photocatalyst. This operationally simple reaction utilizes readily available carboxylic acids to chemoselectively generate reactive alkyl intermediates that are not accessible via conventional two-electron pathways. The organic radical intermediates are efficiently trapped with electrophilic diazo compounds to provide aminated alkanes.Division of Chemistry. Grant Number: 146517

Vaccination of patients with cutaneous melanoma with telomerase-specific peptides

Purpose: A phase I study was conducted to investigate the safety, tolerability, and immunological responses to vaccination with a combination of telomerase-derived peptides GV1001 (hTERT: 611-626) and p540 (hTERT: 540-548) using granulocyte-macrophage colony-stimulating factor (GM-CSF) or tuberculin as adjuvant in patients with cutaneous melanoma. Experimental design: Ten patients with melanoma stages UICC IIb-IV were vaccinated 8times intradermally with either 60 or 300nmole of GV1001 and p540 peptide using GM-CSF as adjuvant. A second group of patients received only 300nmole GV1001 in combination with tuberculin PPD23 injections. HLA typing was not used as an inclusion criterion. Peptide-specific immune responses were measured by delayed-type hypersensitivity (DTH) reactions, in vitro T cell proliferation assays, and cytotoxicity (51-Chromium release) assays for a selected number of clones subsequently generated. Results: Vaccination was well tolerated in all patients. Peptide-specific immune response measured by DTH reactions and in vitro response could be induced in a dose-dependent fashion in 7 of 10 patients. Cloned T cells from the vaccinated patients showed proliferative responses against both vaccine peptides GV1001 and p540. Furthermore, T cell clones were able to specifically lyse p540-pulsed T2 target cells and various pulsed and unpulsed tumor cell lines. Conclusion: These results demonstrate that immunity to hTERT can be generated safely and effectively in patients with advanced melanoma and therefore encourage further trial

Rice Galaxy: An open resource for plant science

Background: Rice molecular genetics, breeding, genetic diversity, and allied research (such as rice-pathogen interaction) have adopted sequencing technologies and high-density genotyping platforms for genome variation analysis and gene discovery. Germplasm collections representing rice diversity, improved varieties, and elite breeding materials are accessible through rice gene banks for use in research and breeding, with many having genome sequences and high-density genotype data available. Combining phenotypic and genotypic information on these accessions enables genome-wide association analysis, which is driving quantitative trait loci discovery and molecular marker development. Comparative sequence analyses across quantitative trait loci regions facilitate the discovery of novel alleles. Analyses involving DNA sequences and large genotyping matrices for thousands of samples, however, pose a challenge to non−computer savvy rice researchers. Findings: The Rice Galaxy resource has shared datasets that include high-density genotypes from the 3,000 Rice Genomes project and sequences with corresponding annotations from 9 published rice genomes. The Rice Galaxy web server and deployment installer includes tools for designing single-nucleotide polymorphism assays, analyzing genome-wide association studies, population diversity, rice−bacterial pathogen diagnostics, and a suite of published genomic prediction methods. A prototype Rice Galaxy compliant to Open Access, Open Data, and Findable, Accessible, Interoperable, and Reproducible principles is also presented. Conclusions: Rice Galaxy is a freely available resource that empowers the plant research community to perform state-of-the-art analyses and utilize publicly available big datasets for both fundamental and applied science