9,133 research outputs found
A Policy Advocacy Dissertation to Increase Transparency and Accountability through Social Return on Investment Analysis
The connection between the funding of public schools and student achievement is complex. Facing dwindling revenue streams, schools and the communities they serve must begin to assess how effectively and efficiently school systems are utilizing federal, state, and local taxpayer resources. As seen in the previous program evaluation and change leadership projects, the Social Return On Investment (SROI) methodology provides a framework that yields a statistically reliable vehicle for doing so that garners trust through transparency. Toward this end, this document advocates for school districts and their boards of education to incorporate the SROI analysis as an essential element of their ongoing district-wide evaluation process
Applying Social Return on Investment Analysis to a Large Central Florida County Public School District
All social organizations are faced with basic questions pertaining to the value they add to their community and how effectively and efficiently they do so. These questions are increasingly being directed to public schools and school districts as well relative to the various programming they offer and the results they achieve. By completing all aspects of a Social Return on Investment (SROI) analysis with fidelity, I have established a statistically reliable baseline SROI ratio based on a comparison of inputs (revenues) to outputs (outcomes). This baseline ratio serves as the foundation for subsequent change initiatives that will lead to district-wide improvement efforts and ultimately yield an enhanced SROI for the school district
Systemic Transformation for College and Career Readiness And Enhanced Social Return on Investment
The transition in motion in the nation and in Florida has the potential to have a short-term adverse impact on high school graduation rates. The transition to more rigorous Florida Standards and their accompanying assessments are expected to promote improved college and career readiness and graduation rates for students in the long term. The disruptive consequences of the transition presents a scenario of short term losses sparking a sense of urgency among educators, parents, students, and the community at-large. This sense of urgency serves as the catalyst for the transformational change initiatives outlined in this document. This Change Leadership Project builds upon the statistically reliable baseline Social Return on Investment (SROI) ratio derived from my previous work, “Applying Social Return on Investment to a Large Central Florida County Public School District” (Lewis, 2014). This establishes a foundation for the methodology incorporated into this inquiry into the application of the theory of change
State-space based mass event-history model I: many decision-making agents with one target
A dynamic decision-making system that includes a mass of indistinguishable
agents could manifest impressive heterogeneity. This kind of nonhomogeneity is
postulated to result from macroscopic behavioral tactics employed by almost all
involved agents. A State-Space Based (SSB) mass event-history model is
developed here to explore the potential existence of such macroscopic
behaviors. By imposing an unobserved internal state-space variable into the
system, each individual's event-history is made into a composition of a common
state duration and an individual specific time to action. With the common state
modeling of the macroscopic behavior, parametric statistical inferences are
derived under the current-status data structure and conditional independence
assumptions. Identifiability and computation related problems are also
addressed. From the dynamic perspectives of system-wise heterogeneity, this SSB
mass event-history model is shown to be very distinct from a random effect
model via the Principle Component Analysis (PCA) in a numerical experiment.
Real data showing the mass invasion by two species of parasitic nematode into
two species of host larvae are also analyzed. The analysis results not only are
found coherent in the context of the biology of the nematode as a parasite, but
also include new quantitative interpretations.Comment: Published in at http://dx.doi.org/10.1214/08-AOAS189 the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Presentation by the University of Nevada, Las Vegas: College of Fine Arts
Program listing performers and works performe
Can I have blood tests to check everything is alright?
Patients often request a general check-up with blood tests. In the UK these are often referred to as an MOT, in allusion to the annual motor vehicle check. Some patients may, however, have unrealistic expectations of medical tests1 and underestimate their potential harms. While agreeing to some blood tests can be an easy way out for a busy clinician, it can expose patients to the harms of over-testing and produce extra workload downstream. We provide a framework for navigating these requests constructively, some elements of which are feasible within a 10 minute consultation
Feeding Two Birds With One Scone? The Relationship Between Teaching and Research for Graduate Students Across the Disciplines
We surveyed over 300 graduate students at a Southeastern research university to increase our understanding of their perceptions of (a) the connection between teaching and research, (b) the means by which integration occurs, and (c) the extent to which teaching and research contribute to a shared skill set that is of value in both contexts. We also examined differences across disciplines in the perception of this teaching-research nexus. Overall, findings indicate that graduate students perceive important relationships between teaching and research, and they point toward opportunities for administrators to promote teaching and research integration
Hydrogen Bonding in Human P450-Substrate Interactions: A Major Contribution to Binding Affinity
The importance of hydrogen bonding, a relatively strong intermolecular force of attraction between molecules in biological systems, is discussed in the respect of P450 substrate affinity towards one or more of the human P450 enzymes that are generally associated with drug and other xenobiotic metabolism. It is shown that calculation of hydrogen bond distances and energies based on simple empirical relationships provide values that agree closely with experimental findings. It is thus possible to estimate the hydrogen bond contribution to P450 enzyme-substrate binding affinity based on modelled interactions and by use of these relatively simple formulae, particularly when employed in conjunction with substrate-lipophilicity relationships. KEYWORDS: hydrogen bonding, cytochrome P450, enzyme-substrate binding, interactions DOMAINS: molecular pharmacology, molecular modeling, physical and theoretical chemistry INTRODUCTION The cytochromes P450 (CYP) constitute a superfamily of heme-thiolate enzymes that have been reported in all biological kingdoms and in most species. Although over 2700 individual P450s have been sequenced, there are only about 10 unique high-resolution crystal structures currently available to investigate various aspects of P450 structure and function. However, it has been proved possible to derive homology models of many P450 enzymes from appropriate crystallographic templates and, for human P450s, the recently reported rabbit CYP2C5 structure appears to be of particular benefit. In many of the P450 structures investigated thus far, including both models and crystallographic coordinates, the ubiquitous importance of hydrogen bonding between enzyme and substrate has been emphasized. Consequently, it can be assumed that this is one of the major contributions to the overall binding energy between substrate and enzyme in P450-substrate interactions. Evidence for this comes from the location of potential hydrogen bond acceptors and donors in P450 crystal structures. For example, in the substrate-bound CYP101 structure, the substrate camphor is positioned directly above the heme moiety for 5-exo hydroxylation by apparently forming a hydrogen bond with the tyrosine-96 residue. There are Lewis: Hydrogen Bonding in P450 TheScientificWorldJOURNAL (2004) 4, 1074-1082 1075 also several hydrophobic residue contacts that cooperatively assist in the binding and orientation of the camphor substrate. In fact, a simple calculation based on compound lipophilicity and average hydrogen bond energy gives a good estimate of the camphor substrate binding energy of CYP101, which is in satisfactory agreement with the experimentally determined value[1]. Estimation of Hydrogen Bond Lengths and Energies However, it is apparent from a survey of the literature that hydrogen bond energies can vary quite significantly depending on the nature of the electronegative atoms involved in the hydrogen bond formation itself An empirical relationship between hydrogen bond energy, HB e , and the inverse of distance has been developed where r xy is the hydrogen bond distance between the two hetero atoms X and Y, which make up the hydrogen bond. Using this equation, it is possible to derive calculated values for hydrogen bond energies that agree closely with experimental data. Consequently, it is reasonable to make use of the empirical relationship described above for the calculation of any hydrogen bond energies likely to be encountered in P450-substrate interactions, such that a more precise estimate of the hydrogen bond contribution to the overall binding affinity can be achieved. However, the employment of an average value of -2 kcal/mol for a hydrogen bond does appear to give rise to satisfactory results in the analysis of such interaction energies Lewis: Hydrogen Bonding in P450 TheScientificWorldJOURNAL (2004) 4, 1074-1082 ? Refers to an estimated value for the hydrogen bond energy based on other reported data for hydrogen bond energies in the literature. 1076 van der Waals radii: Atom, Radius (Ǻ); O, 1.40; N, 1.50; S, 1.85; Cl, 1.80, F, 1.35. The agreement between experimental and calculated hydrogen bond distances is very good (R = 0.98) indicating that the sum of the heavy atom van der Waals radii is a satisfactory estimate of actual hydrogen bond distances observed in crystal structures, thus providing a method for calculating hydrogen bond distances in general. which simply involves division of the constant term by the dielectric constant of the medium, assumed to have a value of 4 at the center of globular proteins. This expression could then be used with some degree of confidence in the estimation of likely hydrogen bond energies encountered in P450-substrate binding interactions. Lewis: Hydrogen Bonding in P450 TheScientificWorldJOURNAL (2004) 4, 1074-1082 1077 FIGURE 1. Comparison between calculated and experimental hydrogen bond lengths using data presented in Hydrogen Bonding and P450-Substrate Binding Affinity Although hydrogen bonds play an important role in many aspects of biological activity at the molecular level, it is clear from extensive structural studies on cytochrome P450 that usually at least one hydrogen bond is formed between the substrate and enzyme active site, resulting in orientation of the former for metabolism at a known position (reviewed in Lewis[17
- …