The G Dwarf Problem Exists in Other Galaxies

Stellar population models with abundance distributions determined from the analytic Simple model of chemical evolution fail to match observations of the nuclei of bulge-dominated galaxies in three respects. First, the spectral energy distribution in the mid-ultraviolet range 2000 < lam < 2400 exceeds observation by ~ 0.6 mag. Most of that excess is due to metal-poor main sequence stars. Second, the models do not reproduce metal-sensitive optical absorption features that arise mainly from red giant stars. Third, the strength of a Ca II index sensitive to hot stars does not jibe with the predicted number of A-type horizontal branch stars. The number of metal poor stars in galaxies is at least a factor of two less than predicted by the Simple model, exactly similar to the ``G Dwarf problem'' in the solar cylinder. Observations at larger radii in local group galaxies indicate that the paucity of metal poor stars applies globally, rather than only in the nuclei. Because of the dominance of metal rich stars, primordial galaxies will have a plentiful dust supply early in their star formation history, and thus will probably have weak Lyman-alpha emission, as is apparently observed. We confirm that early-type galaxies cannot have been formed exclusively from mergers of small all-stellar subsystems, a result already established by dynamical simulations. The constraint of peaked abundance distributions will limit future chemical evolution models. It will also make age estimates for the stellar populations in early type galaxies and bulges more secure.Comment: 14 pages, LaTeX includes 3 postscript figures. Uses AAS LaTeX v 4.0 and times.sty. Accepted for publication in the Astronomical Journal. Postscript available at http://shemesh.gsfc.nasa.gov/~dorman/Ben.htm

Making meat collectivities : entanglements of geneticisation, integration and contestation in livestock breeding

To explore some of the contours of this meat ‘supply chain integration’ - ‘the phrase of the moment’ according to Farmers Weekly - this chapter draws on research conducted as part of a project exploring the effects of the emergence of particular types of genetic knowledge-practice in beef cattle and sheep breeding in the UK and their entanglement with ‘traditional’ ways of knowing and valuing livestock. The research is interested in the production and circulation of genetic knowledge-practices in agriculture, in examining how such knowledge-practices become established and gain legitimacy, how they become tangled up with visual and other traditional knowledge-practices, and in the effects of genetic knowledge-practices on how cattle and sheep are bred and managed and on human-nonhuman animal relationships in livestock farming. The research has increasingly led us to explore the process of ‘geneticisation’ beyond the farm gate, to look at how the establishment of particular genetic truths or ways of rendering ‘life itself’ (Franklin, 2000) are entangled with processes of restructuring and differentiation within UK food systems

Strategies for Systemic Change:Youth Community Organizing to Disruptthe School-to-Prison Nexus

The school disciplinary landscape across the United States changed significantly through the enactment of policies that criminalize students’ behaviors during the 1990s and 2000s. Schools began to involve the police and criminal legal system in school disciplinary issues that used to be handled by school administrators. This shift led youth of Color1 to increasingly come into contact with the juvenile legal system through school suspensions, expulsions, and referrals to alternative schools—what we characterize as the school-toprison nexus. Conceptualizing the school-to-prison pipeline as a nexus, or interlocking system of power over youth, allows us to understand how the criminalization of youth is a systemic problem that demands structural change and interventions across multiple levels of analysis and settings, including local schools, school districts, police departments, and state policies. Although important research has documented the ways that Black and Latino youth are referred to the juvenile legal system through punitive school policies, there has been less attention to the actions youth are taking to critique and dismantle these policies. Youth community organizing (YCO) against the school-to-prison nexus represents an arena of youth activism that deserves further attention and analysis. In this chapter, we define YCO as groups that create spaces for young people to think critically about their everyday social conditions, identify root causes of social problems, and build political power and voice to create policy solutions and change in their communities (Ginwright, Noguera, & Cammarota, 2006; Kirshner, 2015; Watts, Griffith, & Abdul- Adil, 1999)

Measuring player perceptions of advertising in online games

An experiment with 100 participants aged 18-24 was conducted to measure the effects of advertising in an online role-playing computer game on perceived interactivity and other aspects of gameplay experience. Results from a post-test questionnaire revealed insight into players\u27 attitudes toward advertising in video game environments, and reflected varying levels of advertising awareness and recall, message recognition, and factors in purchasing habits. Results suggested that while advertising in online games can sometimes trigger high advertising awareness rates, it can also reduce a game\u27s perceived sense of realism and genuinely annoy players if not appropriately coordinated with the game environment. Whereas previous research has suggested that players usually accept in-game advertising when placed relevantly, this study shows the opposite can occur when advertisers make little or no effort to contextualize their ads within the game world. Results revealed negative attitudes toward in-game advertising from participants who played a version of the game featuring ads, yet females and non-gamers were more accepting of in-game advertising and more often perceived it as interactive than did males and avid gamers. Practical implications and suggestions for further research are discussed

A fast algorithm for calculation of Thêo1

Thêo1 is a frequency stability statistic that is similar to the Allan variance but can provide stability estimates at longer averaging factors and with higher confidence. However, the calculation of Thêo1 is significantly slower than that of the Allan variance, particularly for large data sets, due to a worse computational complexity. A faster algorithm for calculating the "all- τ " version of Thêo1 is developed by identifying certain repeated sums and removing them with a recurrence relation. The new algorithm has a reduced computational complexity, which is equal to that of the Allan variance. Computation time is reduced by orders of magnitude for many data sets. The new, faster algorithm does introduce an error due to accumulated floating-point errors in very large data sets. The error can be compensated for by increasing the numerical precision used at critical steps. The new algorithm can also be used to increase the speed of ThêoBr and ThêoH that are more sophisticated statistics derived from Thêo1

POLYAMINE MODULATION IN ALCOHOLISM: EXAMINATION USING A NOVEL SCREENING PROCEDURE DESIGNED TO PREDICT ANTI-RELAPSE AND NEUROPROTECTIVE EFFICACY

Alcohol dependence is a major public health concern. Despite the FDA’s approval of multiple anti-relapse drugs, relapse rates remain unacceptably high. Furthermore, cognitive deficits among chronic drinkers are evident and are suggested to contribute to relapse risk. Current evidence suggests that several critical features of alcoholism and alcohol-associated neurodegeneration are mechanistically linked to glutamatergic actions; specifically, they appear positively affected by glutamatergic inhibition, particularly inhibition via polyamine modulation of a subpopulation of n-methyl-d-aspartate receptors. The current project was designed to evaluate the performance of two putative polyamine modulators (JR-220 and CP-101,606) in a variety of screens designed to identify the potential to reduce withdrawal severity, neurotoxicity and relapse risk. Screens included a complex organotypic screen designed to assess neuroprotective potential (Experiment 1), a simple behavioral screen designed to assess withdrawal severity (Experiment 2) as well as several more complex behavioral screens designed to examine cue-conditioning during withdrawal (Experiment 3), relapse behavior (Experiment 4), stress-associated consumption (Experiment 5) and binge-like consumption (Experiment 6). An additional open field experiment (Experiment 7) was conducted in order to address interpretational issues concerning activity in Experiments 2-6. Finally, as a first step in moving beyond simple screening, we expanded our binge screen to adhere more closely to an established, validated model of binge consumption (Experiment 8). While some interpretational issues were noted, taken together, the results from these experiments provide strong evidence for both drugs as potential pharmacotherapies for alcoholism and further implicate polyamines and NR2B subunits as critical mechanisms in ETOH consumption and withdrawal

Examining the role of structural dynamics in the assembly and function of the multidrug efflux pump AcrAB-TolC

Membrane efflux pumps are a leading cause of increasing multidrug resistant bacterial infections, which pose a significant threat to global human health. Understanding the mechanisms that underpin their function is critical for the development of inhibitors targeting these systems, with the aim being to ‘revive’ the activities of pre-existing antibiotics known to suffer bacterial resistance. AcrAB-TolC is a membrane spanning, tripartite multidrug efflux pump native to Escherichia coli and prototypical of homologous systems across other ESKAPE bacteria. The work in this thesis investigates the role of structural dynamics in the function, assembly, and inhibition of AcrAB-TolC, with a focus on the membrane fusion protein (MFP) AcrA, to reveal critical information on how these efflux systems work, which could be essential for developing novel methods of inhibition to combat multidrug resistance. Throughout this work, structural mass spectrometry (MS) techniques such as hydrogen deuterium exchange mass spectrometry (HDX-MS) and native MS were used alongside a range of complementary biophysical/biochemical techniques to investigate AcrAB-TolC.This work reveals that AcrA lipidation promotes the propensity of AcrA to form oligomers, whereas a non-lipidated, water soluble AcrA construct (AcrAS) is still monomeric. Moreover, HDX-MS showed AcrAS exhibits increased backbone structural dynamics at pH 6.0 compared to pH 7.4, yet this was largely tempered by the presence of magnesium. In the periplasm, the pH can often be ∼1.7 pH units lower than in the cytosol, and there is a significantly higher concentration of magnesium ions (7.56 times). This suggests a regulatory role of magnesium to help AcrA function within the periplasmic environment. To expand the investigations on AcrAS further, a soluble pseudo-dimer construct (AcrASD) was used to infer biological information on the AcrA functional dimer. It was found the pseudo-dimer has unique structural dynamics compared to AcrA, with extensive protection in the α-helices and in regions of the αβ-barrel and MP domains. Furthermore, whilst AcrAS and AcrASD appeared to bind peptidoglycan similarly, AcrASD had a higher propensity to form higher order complexes with AcrB. This suggests dimerization may help prime the AcrA protomers for interactions with its binding partners.Traditionally, efflux pumps inhibitors (EPIs) have been targeted against AcrB, but none have made it past clinical trials, often due to toxicity issues. This has led to a switch in focus for the next generation of EPIs, with AcrA becoming a promising target. In this work, HDX-MS and native MS were used in combination with molecular dynamics (MD) simulations, to investigate the effect of a recently identified EPI, NSC 60339, on the structural dynamics of AcrAS. The data showed NSC 60339 likely binds to AcrA in a cleft bridging the lipoyl and αβ-barrel domains, stabilising these areas as well as the MP domain which usually exhibits intrinsic disorder; NSC 60339 inhibition of AcrASD presented the same. This work proposes the first mechanism of action regarding an AcrA inhibitor and reveals a promising new way to target the AcrAB-TolC complex.Due to the hydrophobic nature of membrane proteins, a suitable membrane mimetic is required for in vitro investigations. As the AcrAB-TolC multidrug efflux pump spans the entire Gram-negative cell envelope and are therefore membrane proteins, studying them in lipid environments rather than detergents is essential as they provide a more representative environment. In this work, HDX-MS was used to show MBX-3756 stabilises the hydrophobic trap of AcrB in membrane scaffold protein (MSP) nanodiscs. Furthermore, a novel SMALP-liposome-SMALP assay was utilised to show that previously designed AcrB antimicrobial peptides did not make the AcrB trimer, purified in styrene maleic acid lipid particles (SMALPs), dissociate into monomers. Lastly, assembly of the AcrAB-TolC complex was probed using two different pull-down assays and native polyacrylamide gel electrophoresis (PAGE), however the heterogeneity and hydrophobicity of SMALPs complicated these investigations, combined with the slow energetics of this assembly in vitro.<br/

Closing the California Clean Energy Divide: Reducing Electric Bills in Affordable Multifamily Rental Housing with Solar+storage

This economic analysis indicates that pairing solar PV with battery storage systems can deliver significant electricity bill savings for California affordable housing residents and property owners.Battery storage is emerging as an effective new strategy for reducing electricity costs for affordable multifamily rental housing in California. Battery storage systems not only provide economic returns today, they can also preserve the value of solar in an evolving policy and regulatory environment. Because batteries empower owners of solar photovoltaic (PV) systems to take control of the energy they produce and when they consume it, storage can deliver deeper cost reductions that can be shared among affordable housing owners, developers, and tenants.California has installed numerous integrated solar and battery storage projects; however, few have served lowincome tenants or owners of affordable rental housing. This disparity is due to many factors, including a lack of information about the economics of these systems in multifamily housing. To provide that needed information, Clean Energy Group, California Housing Partnership, and Center for Sustainable Energy, with analytical support from Geli, are embarking on a series of reports on solar and storage in California affordable multifamily rental housing.This first report examines the utility bill impacts of adding battery storage to stand-alone solar in affordable rental housing facilities in California's three investor-owned utility service territories, each with different rate structures. It is the first such report ever completed on these technologies in this sector in California.The report reaches several key conclusions:Under current utility rate tariffs, the combination of solar and storage technologies could virtually eliminate electric bills for many owners of affordable housing properties. Unlike stand-alone solar, which reduces energy consumption expenses but does little to offset demand related charges, a properly sized solar and battery storage system can eliminate nearly all electricity expenses, resulting in an annual electric utility bill of less than a few hundred dollars in some cases.It makes good economic sense today for solar and battery storage to be installed in affordable multifamily rental housing in California. The addition of battery storage to solar improves the economics of each property analyzed across all utility territories, reducing project payback by over three years in some cases.The addition of storage technologies has the potential to nearly double stand-alone solar electricity bill savings at about a third of the cost of solar. For example, the addition of a $112,100 battery storage system to a$385,000 solar installation increased savings from $15,000 per year to$27,900, an 85 percent increase in savings for only a 29 percent increase in cost

Acute rotator cuff tendinopathy: does ice, low load isometric exercise, or a combination of the two produce an analgaesic effect?

This document is the Accepted Manuscript version of the following article: Parle PJ, Riddiford-Harland DL, Howitt CD, et al. 'Acute rotator cuff tendinopathy: does ice, low load isometric exercise, or a combination of the two produce an analgaesic effect?.' Br J Sports Med 2017;51:208-209, doi: http://dx.doi.org/10.1136/bjsports-2016-096107.Rotator cuff tendinopathies are the most commonly diagnosed musculoskeletal shoulder conditions and are associated with pain, weakness and loss of function.1 Tendon swelling may be associated with tendinopathy and may result from acute overload.2–3 An increase in tendon cells (tenocytes) and upregulation of large molecular weight proteoglycans, such as aggrecan, may increase tendon water content.2 There is uncertainty as to whether the swelling is related to the pain or is instead an observed but unrelated phenomenon. Weakness detected clinically may be due to pain inhibition.4–5 Early treatment of acute rotator cuff tendinopathy involves patient education and relative rest, and may include non-steroidal anti-inflammatory drugs (NSAIDs) to reduce pain, swelling and inflammation. Subacromial corticosteroid injections are also used to achieve the same purpose. These techniques show low to moderate evidence of reducing short-term pain but they do not improve function.6 The medications have side effects such as gastrointestinal tract complaints,7 and corticosteroids may damage tendon tissue.8 Identifying alternative ways to control pain and inflammation may be warranted. Two clinical procedures to manage RC tendinopathy include ice wraps and isometric exercise, however, there are no empirical data supporting their use. This pilot study, conducted at the Illawarra Sports Medicine Clinic, NSW, Australia, was designed to test (1) the short term analgaesic effect of these interventions and (2) the feasibility of a larger clinical trial for adults diagnosed with acute rotator cuff tendinopathy (<12 weeks).Peer reviewe