Cosmological Constraints on Unstable Particles: Numerical Bounds and Analytic Approximations

Many extensions of the Standard Model predict large numbers of additional unstable particles whose decays in the early universe are tightly constrained by observational data. For example, the decays of such particles can alter the ratios of light-element abundances, give rise to distortions in the cosmic microwave background, alter the ionization history of the universe, and contribute to the diffuse photon flux. Constraints on new physics from such considerations are typically derived for a single unstable particle species with a single well-defined mass and characteristic lifetime. In this paper, by contrast, we investigate the cosmological constraints on theories involving entire ensembles of decaying particles --- ensembles which span potentially broad ranges of masses and lifetimes. In addition to providing a detailed numerical analysis of these constraints, we also formulate a set of simple analytic approximations for these constraints which may be applied to generic ensembles of unstable particles which decay into electromagnetically-interacting final states. We then illustrate how these analytic approximations can be used to constrain a variety of toy scenarios for physics beyond the Standard Model. For ease of reference, we also compile our results in the form of a table which can be consulted independently of the rest of the paper. It is thus our hope that this work might serve as a useful reference for future model-builders concerned with cosmological constraints on decaying particles, regardless of the particular model under study.Comment: 41 pages, LaTeX, 12 figures, 4 table

The sound of silence: the absence of public service values in Canadian media discourse about the CBC

Public service broadcasting (PSB) across the world is in crisis. This article examines how, if at all, normative academic ideals of public service broadcasting inform discussion about the Canadian Broadcasting Corporation (CBC) in Canadian news media. The researchers undertook a quantitative (N = 467) and qualitative (n = 29) content analysis of five years of Canadian news media coverage about the CBC published between January 1, 2009, and April 30, 2014. Their systematic analysis of this research found little connection was made between the CBC and discussions of public service values. This study contends that the pre-eminence of neoliberal discourse represents a serious assault to broadcasters with a public service ethos

The Characterization Of Natural Ingredients As Pharmaceutical Excipients In Paracetamol Tablets

Excipients used in pharmaceuticals are inactive ingredients that play a big role in drug formulations, and drug delivery systems. Binders are a type of pharmaceutical excipient that is crucial to the stability, physical characteristics, and cohesiveness of the tablet. Fully synthetic binders, such as polyethylene glycol (PEG), are commonly used due to their great formulation traits; however, these materials may have a slow dissolution rate, reduced bioavailability, or the potential to cause allergic reactions. Due to these limitations, natural excipients would be a great alternative due to their biocompatibility and faster dissolution rate. The purpose of this research was to characterize natural ingredients including d-sorbitol, d-allulose, tamarind gum, xanthan gum, guar gum, and pectin as pharmaceutical excipients with active pharmaceutical ingredient (API) paracetamol (APAP, acetaminophen). One excipient is used per tablet formulation with APAP to determine the influence on tablet characteristics. Another purpose of the research is to develop a better method for the formulation of 325 mg tablets. APAP tablets are created through wet granulation within 3D-printed molds, before being left to dry in a desiccant cabinet. After drying the tablets are characterized through image analysis with image pro software, dissolution using the BIO-DIS reciprocating Cylinder Apparatus, disintegration using 100 Disintegration Apparatus, Fourier-transform infrared spectroscopy (FTIR) absorbance accomplished with the Cary 630 FTIR, thermal stability with the Mettler Toledo DSC 3 STARe System, and crystal structure analysis with the XRD-7000 X-Ray Diffractometer Maxima. It has been concluded that natural excipients are compatible with APAP within the tablet matrix. 3D molds were an effective medium to produce granules through wet granulation due to the method\u27s efficiency and yielding granules with consistent shapes. Sugar excipients were found to have a rapid disintegration time compared to polysaccharides and synthetic PEG. The dissolution test found that all the excipients except for xanthan gum had a faster rate of dissolution than PEG. Natural excipients also have little effect on APAP’s crystal structure and melting point temperature shown through XRD and DSC respectively. FTIR analysis has shown that natural excipients will have less of an impact on APAP’s structure than synthetic PEG

Assessing Essential Fish Habitat for Bluefish Pomatomus saltatrix (Linnaeus, 1766), in Virginia\u27s Portion of Chesapeake Bay and Near Shore Coastal Waters, 1988-1999

The Magnuson - Stevens Fishery Conservation and Management Act of 1996 strengthened the ability of the ational Marine Fisheries Service and other Fisheries Management Councils to protect and conserve habitats of marine, estuarine, and anadromous fin.fish mollusks, and crustaceans. The 1996 amendments to the act require the identification and description of essential habitat for the managed species, minimization of adverse effects on essential fish habitat (EFH) caused by fishing, and encouragement toward the conservation and enhancement of essential fish habitats. Essential fish habitat is broadly defined to include those waters and substrate necessary to fish for spawning breeding feeding, or growth to maturity (NMFS 2000). The ational Marine Fisheries Service identified bluefish (Pomatomus saltatrix) as a species for which EFH must be described. Bluefish are considered one of the most important recreational species along the Atlantic coast of the United States and have long captured the attention of saltwater anglers. Our objective is the dissemination of information about bluefish essential fish habitat in Virginia\u27s tidal waters based on long-term data collections

The estimation of a preference-based measure of health from the SF-36

This paper reports on the findings of a study to derive a preference-based measure of health from the SF-36 for use in economic evaluation. The SF-36 was revised into a six-dimensional health state classification called the SF-6D. A sample of 249 states defined by the SF-6D have been valued by a representative sample of 611 members of the UK general population, using standard gamble. Models are estimated for predicting health state valuations for all 18,000 states defined by the SF-6D. The econometric modelling had to cope with the hierarchical nature of the data and its skewed distribution. The recommended models have produced significant coefficients for levels of the SF-6D, which are robust across model specification. However, there are concerns with some inconsistent estimates and over prediction of the value of the poorest health states. These problems must be weighed against the rich descriptive ability of the SF-6D, and the potential application of these models to existing and future SF-36 data set

Group Supervision Attitudes: Supervisory Practices Fostering Resistance to Adoption of Evidence-Based Practices

The focus of this study was to qualitatively evaluate worker’s attitudes about clinical supervision. It is believed that poor attitudes toward clinical supervision can create barriers during supervision sessions. Fifty-one participants within a social services organization completed an open-ended questionnaire regarding their clinical supervision experiences. Results suggest four key areas which appear to be strong factors in workers’ experiences and attitudes regarding group supervision: a. facilitator’s skill level; b. creativity; c. utilization of technology; and d. applicability. For organizations interested in overcoming potential barriers to adopting best practices, effectively addressing workers’ negative attitudes toward group supervision would be a worthy endeavor

On the Origin of Conspiracy Theories

Conspiracy theories are rather a popular topic these days, and a lot has been written on things like the meaning of conspiracy theory, whether it's ever rational to believe conspiracy theories, and on the psychology and demographics of people who believe conspiracy theories. But very little has been said about why people might be led to posit conspiracy theories in the first place. This paper aims to fill this lacuna. In particular, I shall argue that, in open democratic societies, citizens justifiably presuppose that the epistemic authorities—journalists, academics, scientists, and so on—are engaged in a good faith pursuit of the truth. This presupposition generates certain normative expectations on the behaviors of the epistemic authorities—they ought to be open to new evidence, possess a healthy degree of skepticism, be willing to engage with opponents, and so on. So, when an epistemic authority is presented with some putatively anomalous data or an alternative hypothesis for some event or phenomena, people expect the epistemic authority to respond in a way that is consonant with these norms. In some instances, however, the epistemic authorities do not respond in this way and instead are dogmatic, dismissive, and engage in ad hominem. From the point of view of the citizen, there's a tension here between how the epistemic authorities ought to behave and how they have, in fact, behaved which is best resolved either by taking the epistemic authorities less seriously or by positing a conspiracy theory. Put another way, the failure of the epistemic authorities to adhere to the norms by which we take them to be governed when presented with apparent anomalies or alternative hypotheses is one reason for which one might initially posit a conspiracy theory