The role of thermal instabilities in star formation

Thermal and magnetic effects on uniform medium stability in study of thermal instability role in star formatio

Principles of Contract Law Applied to Entertainment and Sports Contracts: A Model for Balancing the Rights of the Industry with Protecting the Interests of Minors

This Article discusses the context of common law and statutory materials dealing with minors who participate in the entertainment and sports fields. The Article describes the changes undertaken as a result of several notorious cases involving prominent child actors, and how the California legislature dealt with issues ranging from set asides of income, approval of contracts by a competent court of jurisdiction, recognition of the legitimate interests of all parties to the contract, to principles under which a minor would be precluded from disaffirming a contract. The Article then applies and extends the principles developed in entertainment contracts to minors who participate in professional athletics and offers concrete suggestions for perfecting a balance in interests by focusing on assuring the minor with representation by “qualified counsel experienced with entertainment industry law and practices

Chandra Observation of an X-ray Flare at Saturn: Evidence for Direct Solar Control on Saturn's Disk X-ray Emissions

Saturn was observed by Chandra ACIS-S on 20 and 26-27 January 2004 for one full Saturn rotation (10.7 hr) at each epoch. We report here the first observation of an X-ray flare from Saturn's non-auroral (low-latitude) disk, which is seen in direct response to an M6-class flare emanating from a sunspot that was clearly visible from both Saturn and Earth. Saturn's disk X-ray emissions are found to be variable on time scales of hours to weeks to months, and correlated with solar F10.7 cm flux. Unlike Jupiter, X-rays from Saturn's polar (auroral) region have characteristics similar to those from its disk. This report, combined with earlier studies, establishes that disk X-ray emissions of the giant planets Saturn and Jupiter are directly regulated by processes happening on the Sun. We suggest that these emissions could be monitored to study X-ray flaring from solar active regions when they are on the far side and not visible to Near-Earth space weather satellites.Comment: Total 12 pages including 4 figure

Master Franchising as an Entry Strategy: Marketing and Legal Implications

In this paper the authors investigate the establishment of franchise agreements as a viable alternative to enter a foreign market. Specifically, the spotlight is on the strategy called master franchising. The authors first review the concept of franchising and identify master franchising as a strategic option. Next, they focus on the mechanics of structuring the required agreements. Last, the authors explore strategies, trends, and current opportunities and limitations of international franchising

TB153: A Long-Term Study of an Oak Pine Forest Ecosystem: Techniques Manual for the Holt Research Forest

The manual is a compilation of the study techniques used for the long-term forest ecosystem research project at the Holt Research Forest in Arrowsic, Maine, plus brief evaluations of each method\u27s advantages and drawbacks. It is based on 12 years of work by a team of three university professors, an associate scientist who has lived on the forest since 1983, a research assistant, several graduate students, and numerous undergraduate field assistants. We hope this manual will be useful to other researchers planning, or already involved in, other forest ecosystem studies.https://digitalcommons.library.umaine.edu/aes_techbulletin/1053/thumbnail.jp

Thermal Instability-Induced Interstellar Turbulence

We study the dynamics of phase transitions in the interstellar medium by means of three-dimensional hydrodynamic numerical simulations. We use a realistic cooling function and generic nonequilibrium initial conditions to follow the formation history of a multiphase medium in detail in the absence of gravity. We outline a number of qualitatively distinct stages of this process, including a linear isobaric evolution, transition to an isochoric regime, formation of filaments and voids (also known as "thermal" pancakes), the development and decay of supersonic turbulence, an approach to pressure equilibrium, and final relaxation of the multiphase medium. We find that 1%-2% of the initial thermal energy is converted into gas motions in one cooling time. The velocity field then randomizes into turbulence that decays on a dynamical timescale E_k ~ t^-n, 1 < n < 2. While not all initial conditions yield a stable two-phase medium, we examine such a case in detail. We find that the two phases are well mixed with the cold clouds possessing a fine-grained structure near our numerical resolution limit. The amount of gas in the intermediate unstable phase roughly tracks the rms turbulent Mach number, peaking at 25% when M_rms ~ 8, decreasing to 11% when M_rms ~ 0.4.Comment: To appear in the ApJ Letters, April 2002; 5 pages, 3 color figures, mpeg animations available at http://akpc.ucsd.edu/ThermalLetter/thermal.htm

Critical behavior of the three-dimensional XY universality class

We improve the theoretical estimates of the critical exponents for the three-dimensional XY universality class. We find alpha=-0.0146(8), gamma=1.3177(5), nu=0.67155(27), eta=0.0380(4), beta=0.3485(2), and delta=4.780(2). We observe a discrepancy with the most recent experimental estimate of alpha; this discrepancy calls for further theoretical and experimental investigations. Our results are obtained by combining Monte Carlo simulations based on finite-size scaling methods, and high-temperature expansions. Two improved models (with suppressed leading scaling corrections) are selected by Monte Carlo computation. The critical exponents are computed from high-temperature expansions specialized to these improved models. By the same technique we determine the coefficients of the small-magnetization expansion of the equation of state. This expansion is extended analytically by means of approximate parametric representations, obtaining the equation of state in the whole critical region. We also determine the specific-heat amplitude ratio.Comment: 61 pages, 3 figures, RevTe

Factors that impact on recruitment to randomised trials in health care: a qualitative evidence synthesis

BACKGROUND: Randomised trials (also referred to as 'randomised controlled trials' or 'trials') are the optimal way to minimise bias in evaluating the effects of competing treatments, therapies and innovations in health care. It is important to achieve the required sample size for a trial, otherwise trialists may not be able to draw conclusive results leading to research waste and raising ethical questions about trial participation. The reasons why potential participants may accept or decline participation are multifaceted. Yet, the evidence of effectiveness of interventions to improve recruitment to trials is not substantial and fails to recognise these individual decision-making processes. It is important to synthesise the experiences and perceptions of those invited to participate in randomised trials to better inform recruitment strategies. OBJECTIVES: To explore potential trial participants' views and experiences of the recruitment process for participation. The specific objectives are to describe potential participants' perceptions and experiences of accepting or declining to participate in trials, to explore barriers and facilitators to trial participation, and to explore to what extent barriers and facilitators identified are addressed by strategies to improve recruitment evaluated in previous reviews of the effects of interventions including a Cochrane Methodology Review. SEARCH METHODS: We searched the Cochrane Library, Medline, Embase, CINAHL, Epistemonikos, LILACS, PsycINFO, ORRCA, and grey literature sources. We ran the most recent set of searches for which the results were incorporated into the review in July 2017. SELECTION CRITERIA: We included qualitative and mixed-methods studies (with an identifiable qualitative component) that explored potential trial participants' experiences and perceptions of being invited to participate in a trial. We excluded studies that focused only on recruiters' perspectives, and trials solely involving children under 18 years, or adults who were assessed as having impaired mental capacity. DATA COLLECTION AND ANALYSIS: Five review authors independently assessed the titles, abstracts and full texts identified by the search. We used the CART (completeness, accuracy, relevance, timeliness) criteria to exclude studies that had limited focus on the phenomenon of interest. We used QSR NVivo to extract and manage the data. We assessed methodological limitations using the Critical Skills Appraisal Programme (CASP) tool. We used thematic synthesis to analyse and synthesise the evidence. This provided analytical themes and a conceptual model. We used the GRADE-CERQual (Confidence in the Evidence from Reviews of Qualitative research) approach to assess our confidence in each finding. Our findings were integrated with two previous intervention effectiveness reviews by juxtaposing the quantitative and qualitative findings in a matrix. MAIN RESULTS: We included 29 studies (published in 30 papers) in our synthesis. Twenty-two key findings were produced under three broad themes (with six subthemes) to capture the experience of being invited to participate in a trial and making the decision whether to participate. Most of these findings had moderate to high confidence. We identified factors from the trial itself that influenced participation. These included how trial information was communicated, and elements of the trial such as the time commitment that might be considered burdensome. The second theme related to personal factors such as how other people can influence the individual's decision; and how a personal understanding of potential harms and benefits could impact on the decision. Finally, the potential benefits of participation were found to be key to the decision to participate, namely personal benefits such as access to new treatments, but also the chance to make a difference and help others. The conceptual model we developed presents the decision-making process as a gauge and the factors that influence whether the person will, or will not, take part. AUTHORS' CONCLUSIONS: This qualitative evidence synthesis has provided comprehensive insight into the complexity of factors that influence a person's decision whether to participate in a trial. We developed key questions that trialists can ask when developing their recruitment strategy. In addition, our conceptual model emphasises the need for participant-centred approaches to recruitment. We demonstrated moderate to high level confidence in our findings, which in some way can be attributed to the large volume of highly relevant studies in this field. We recommend that these insights be used to direct or influence or underpin future recruitment strategies that are developed in a participant-driven way that ultimately improves trial conduct and reduces research waste