cssi/SciSciGPT-SciSciNet huggingface dataset:
The Causal Effects of Rule of Law and Property Rights on Fiscal Capacity

Governments of rich nations tend to have high fiscal capacity while being credibly limited in their use of revenues (Johnson and Koyama 2017). This poses a puzzle. A government powerful enough to effectively enforce property rights under the rule of law is also powerful enough to prey upon the its citizens (Weingast 1995, 1993). Scholars have suggested that a credible commitment to non-predatory governance is prior to achieving high fiscal capacity (e.g., North and Weingast 1989). This is because citizens’ willingness to supply resources is a function of how they expect fiscal capacity to be used. (E.g., if they expect predatory governance, they will make fiscal capacity costly to obtain.) We analyze a panel of countries during the 1970-2015 period. We identify large, sustained jumps in how countries score on a measure of legal system and property rights quality. Using various matching methodologies (Rosenbaum and Rubin 1983), we attempt to identify post-treatment effects on measures of fiscal capacity.
Organophotoredox/palladium dual catalytic decarboxylative Csp3-Csp3 coupling of carboxylic acids and π-electrophiles.

A dual catalytic decarboxylative allylation and benzylation method for the construction of new C(sp3)–C(sp3) bonds between readily available carboxylic acids and functionally diverse carbonate electrophiles has been developed. The new process is mild, operationally simple, and has greatly improved upon the efficiency and generality of previous methodology. In addition, new insights into the reaction mechanism have been realized and provide further understanding of the harnessed reactivity.
On the possible coexistence of two different regimes of metal particle combustion

Abstract The coexistence of two regimes of aluminum (Al) particle combustion is discussed. A slower regime occurs at a low energy accommodation coefficient (EAC) and is usually observed in Al combustion experiments. A faster regime at high EAC is also possible. The combustion enhancement observed for pre-treated Al particles can be interpreted as a switch from the slower combustion regime to the faster regime. The value of EAC is controlled by the thermionic emission of electrons. A relationship between Al particle pre-treatment and the work function, which governs the thermionic emission, and, therefore, the EAC, is a subject of further studies.
Phenoscreening: a developmental approach to research domain criteria-motivated sampling.

Background To advance early identification efforts, we must detect and characterize neurodevelopmental sequelae of risk among population-based samples early in development. However, variability across the typical-to-atypical continuum and heterogeneity within and across early emerging psychiatric/neurodevelopmental disorders represent fundamental challenges to overcome. Identifying multidimensionally determined profiles of risk, agnostic to DSM categories, via data-driven computational approaches represents an avenue to improve early identification of risk. Methods Factor mixture modeling (FMM) was used to identify subgroups and characterize phenotypic risk profiles, derived from multiple parent-report measures of typical and atypical behaviors common to autism spectrum disorder, in a community-based sample of 17- to 25-month-old toddlers (n = 1,570). To examine the utility of risk profile classification, a subsample of toddlers (n = 107) was assessed on a distal, independent outcome examining internalizing, externalizing, and dysregulation at approximately 30 months. Results FMM results identified five asymmetrically sized subgroups. The putative high- and moderate-risk groups comprised 6% of the sample. Follow-up analyses corroborated the utility of the risk profile classification; the high-, moderate-, and low-risk groups were differentially stratified (i.e., HR > moderate-risk > LR) on outcome measures and comparison of high- and low-risk groups revealed large effect sizes for internalizing (d = 0.83), externalizing (d = 1.39), and dysregulation (d = 1.19). Conclusions This data-driven approach yielded five subgroups of toddlers, the utility of which was corroborated by later outcomes. Data-driven approaches, leveraging multiple developmentally appropriate dimensional RDoC constructs, hold promise for future efforts aimed toward early identification of at-risk-phenotypes for a variety of early emerging neurodevelopmental disorders.
Invariant homology on standard model manifolds

Torus-fibered Calabi-Yau threefolds Z, with base d9 and fundamental group π1(Z) = 2 × 2 , are reviewed. It is shown that Z = X/(2 × 2), where X = B × 1B ' are elliptically fibered Calabi-Yau threefolds that admit a freely acting 2 × 2 automorphism group. B and B ' are rational elliptic surfaces, each with a 2 × 2 group of automorphisms. It is shown that the 2 × 2 invariant classes of curves of each surface have four generators which produce, via the fiber product, seven 2 × 2 invariant generators in H 4(X,). All invariant homology classes are computed explicitly. These descend to produce a rank seven homology group H 4(Z,) on Z. The existence of these homology classes on Z is essential to the construction of anomaly free, three family standard-like models with suppressed nucleon decay in both weakly and strongly coupled heterotic superstring theory.
Who Belongs among the “We?”: Hospitality, the Gospel, and the Systemic Sin of Christian Higher Education against LGBTQ+ Students:

The invitation of Jesus to come and belong with him and with all those who follow him is at the very heart of the gospel. However, not all who accept this invitation feel welcome and experience bel...
Evolutionary relationships among shell proteins of carboxysomes and metabolosomes

Bacterial microcompartments (BMCs) are self-assembling prokaryotic organelles which encapsulate enzymes within a polyhedral protein shell. The shells are comprised of only two structural modules, distinct domains that form pentagonal and hexagonal building blocks, which occupy the vertices and facets, respectively. As all BMC loci encode at least one hexamer-forming and one pentamer-forming protein, the evolutionary history of BMCs can be interrogated from the perspective of their shells. Here, we discuss how structures of intact shells and detailed phylogenies of their building blocks from a recent phylogenomic survey distinguish families of these domains and reveal clade-specific structural features. These features suggest distinct functional roles that recur across diverse BMCs. For example, it is clear that carboxysomes independently arose twice from metabolosomes, yet the principles of shell assembly are remarkably conserved.
The Paradox of Prejudicially Applying Valid Academic Standards: A Historical Case Study in the Ethics of Academic Administration

Among the 60 or so Catholic colleges and universities operating in the United States in the late nineteenth-century, the 24 founded by the Jesuits had the highest academic standards. But the educational merit of the Jesuit B.A. was challenged in the 1890s when Harvard Law School (HLS) declared that only “respectable” bachelor’s degrees of certain colleges would qualify an applicant for admission. None of these were Catholic institutions, whose graduates where therefore excluded from the leading law school in the country. The Harvard president and deans maintained that the identification of “respectable” degrees was based solely upon neutral standards of academic quality. But Catholic educators protested vigorously, and a decade-long debate ensued between Harvard administrators and the Catholics as to whether and how Jesuit education was academically deficient. The decisions of Harvard’s academic administrators had an invidious discriminatory effect and did originate in cultural prejudice against Catholicism. However, the Harvard administrators believed – sincerely and justifiably – that they were making neutral academic judgments. This historical case study examines how the complexity of academic administration fostered and disguised this paradox.
Cost-effectiveness analysis of mechanical thrombectomy in acute ischemic stroke.

Object Mechanical thrombectomy is increasingly being used for the treatment of large-vessel ischemic stroke in patients who arrive outside of the 3-hour tissue plasminogen activator time window. In this study, the authors evaluated the cost and effectiveness of mechanical thrombectomy compared with standard medical therapy in patients who are ineligible to receive tissue plasminogen activator. Methods Clinical outcomes of an open-label study of mechanical thrombectomy were compared with a hypothetical control group with a lower recanalization rate (18 vs 60%) and a lower rate of symptomatic intracranial hemorrhage (0.6 vs 7.8%) than the active treatment group. A Markov cost-effectiveness model was built to compare the health benefits and costs associated with mechanical thrombectomy compared with standard medical therapy. All probabilities, quality-of-life factors, and costs were estimated from the published literature. Univariate sensitivity analyses were performed to assess how variations in model param...
Issues and Approaches for Developing Learner-Centered Technology

Abstract As computing technology has evolved, there has been significant research and a range of approaches exploring the use of computers for learning. Traditionally, the prevalent approach when developing software has been a user-centered approach that focuses on software usability to help experts in some practice effectively engage in their work. However, in recent years, researchers have come to understand that a different approach—a learner-centered approach—is needed to design tools that help novices in some practice do and learn the work involved in that practice. Rather than solely focusing on the conceptual gulfs that lie between tool users and their tools, learner-centered tools primarily focus on addressing the conceptual gulf between a learner's novice expertise in some practice and the expertise of an expert in that practice. In this chapter, we discuss some major approaches that have been considered for learner-centered technologies by describing software based on behaviorist, information processing, and social constructivist approaches. Expanding on the latter two approaches, we will focus on two types of learner-centered software. We will look at intelligent tutoring systems and how they oversee a learner's work to provide assistance when learners encounter problems as they are working on certain tasks. We will also look at scaffolded software that incorporates specific functionalities and user interface features to support learners as they use the tool to engage in new activity. For each type of software, we will discuss the issues, approaches, and tradeoffs involved in designing, implementing, and evaluating the software given its learner-centered focus. Finally, we will consider emerging wireless, handheld technologies, to discuss the new kinds of functionalities offered by these technologies, their possible impact on learning, and the challenges that developers face in creating educationally effective software given the constraints of these technologies.
A Model and Sample Case for Teaching the Business Value of Information Technology

This paper proposes an Information Technology Business Value (ITBV) model for teaching discovery of value as applied to common information technology-enabled organizational processes. The model is comprised of 1) a two-dimensional application matrix, which focuses on what business value is and where it can be applied in the organization; and 2) a set of action “triggers” that focus on the “how to” of discovering value opportunities. The horizontal axis of the matrix (the what) identifies five value parameters: quality, cost, speed, innovation and relationship. The vertical matrix identifies five functional areas where IT-enabled value propositions can be applied. The action triggers, based on principles of process re-engineering, activate the process to guide students through the discovery of meaningful value opportunities. A recommended process for using the model suggests initial discussions about business value, value added functions in the organization, and the enabling role of IT via process re-engineering. The application of the model follows this and includes case analysis and documentation. A suggested schema for documenting uncovered opportunities includes identification of proposed activities (action items), a description of the value added and where it will be applied, and the appropriate technology for each action. A sample case, with sample completed action items, is included. As a basic learning tool, the model is not intended as a structure for the thorough, complex analysis of opportunities, although it can appropriately be used as the initial step in that process. Rather, its contribution is in illuminating and strengthening the fundamental connectivity between IT and business value contribution in a simple active-learning approach that is accessible to those learning about the value and organizational impact of information technology.
Breaking the Curse of Cardinality on Bitmap Indexes

Bitmap indexes are known to be efficient for ad-hoc range queries that are common in data warehousing and scientific applications. However, they suffer from the curse of cardinality, that is, their efficiency deteriorates as attribute cardinalities increase. A number of strategies have been proposed, but none of them addresses the problem adequately. In this paper, we propose a novel binned bitmap index that greatly reduces the cost to answer queries, and therefore breaks the curse of cardinality. The key idea is to augment the binned index with an Order-preserving Bin-based Clustering (OrBiC) structure. This data structure significantly reduces the I/O operations needed to resolve records that can not be resolved with the bitmaps. To further improve the proposed index structure, we also present a strategy to create single-valued bins for frequent values. This strategy reduces index sizes and improves query processing speed. Overall, the binned indexes with OrBiC great improves the query processing speed, and are 3 --- 25 times faster than the best available indexes for high-cardinality data.
Designing performance into i960 superscalar microprocessors

The author outlines two major development efforts designed to maintain the price performance advantage of the Intel i960 family of 32-b embedded processors. These are trace-driven simulation and profile-driven compilers. The trace-driven simulation environment is used to evaluate micro-architectural trade-offs in microprocessor design. This simulation methodology allows the simulation of real applications under a wide variety of process and system configurations. Two-pass profile driven compiler technology allows a compiler to optimize a program based on the execution of that program. >
The development of hospital financial accounting in the USA

This paper examines the history of financial accounting in American hospitals from the turn of the twentieth century to the present. It argues that, prior to the 1970s, the financial accounting practices of hospitals differed significantly from their counterparts in the business world as health-service organisations, institutions and legislation rather than accounting bodies and standards were the principal influence on their development. The paper moreover argues that the increasing influence of the Financial Accounting Standards Board on financial accounting in American hospitals has resulted in a growing convergence between accounting practices in hospitals and the wider economy since the early 1970s.
The proteins CMT3, UHRF1 and ESP1 repress select transposable elements in the model plant Arabidopsis thaliana

Transposable elements (TEs) are mobile fragments of DNA that occupy large portions of eukaryotic genomes and can harmfully mutate the genome when they are active. To suppress TE activity, eukaryotic cells repress TE transcription using multiple elaborate mechanisms that are not well understood. The Autumn 2013 Molecular Genetics 5601 Laboratory course aimed to discover specific proteins in the plant Arabidopsis thaliana which act to maintain the epigenetic silencing of multiple TEs. In half of a semester we successfully genotyped 17 homozygous mutants, measured the expression of seven different TEs by qRT-PCR in these confirmed mutant lines, and additionally investigated the DNA methylation levels of specific mutant-TE combinations by McrBC-PCR. From our analysis we identified three proteins that function to suppress TE transcription. We unexpectedly found that the putative mRNA-binding protein ESP1 functions to maintain the silencing of particular select types of TEs, and the DNA methylation mutants cmt3 and uhrf1 have only minor reactivation of specific TEs, not a genome-wide global TE activation as previously suggested. Our data demonstrates that an undergraduate laboratory course can successfully identify new proteins involved in the repression of TEs while learning the fundamentals of molecular genetics and experimental biological research.
Response competition in monkeys' solution of PAN ambiguous-cue problems

Abstract Four monkeys were tested on a 2-choice object discrimination task involving 3 stimuli: P, positive and consistently rewarded; N, negative and consistently nonrewarded; and A, ambiguously rewarded depending upon whether paired with P on PA trials or N on NA trials. A preestablished prompt indicated the rewarded object (P on PA, A on NA trials) on initial training trials during which the ratio of PA to NA trials was 4/4, 4/8, or 4/12. All training trials were followed by 16 nonprompted test trials (8 PA and 8 NA). Performance on PA test trials decreased monotonically as a function of the preceding decreasing PA/NA ratios supporting the hypothesis of competition among independently acquired approach tendencies to P and A objects. This competition occurred even on training trials of 4/12 problems during which performance on PA trials was at chance despite the presence of the prompt. Corroborating and extending those of previous research, these results offer substantial additional support for the interfering-cue hypothesis.
Renal reabsorption of bicarbonate in puppies: effect of extracellular volume contraction on the renal threshold for bicarbonate.

Extract: It has been recognized for many years that infants have lower concentrations of bicarbonate in plasma than older children and adults, due neither to a limited renal capacity to excrete hydrogen ion nor to a reduced capacity for reabsorption of bicarbonate, but to a low renal threshold for bicarbonate. The purpose of the present investigation was to determine whether the neonate and young of another species also could be shown to have a “physiologic acidosis” and, if so, to use this model for exploration of factors that might influence the threshold for bicarbonate. Mean pH of blood and concentration of bicarbonate in plasma in 11 young suckling puppies were 7.24 ± 0.018 and 18.2 ± 0.55 mmoles/liter, respectively, levels considerably lower than those found in adult dogs. In all but one animal pH of urine was below 6.0. Inasmuch as puppies thus appear to be in a state of “physiologic acidosis” and to have no limitation in acidification of the urine, we feel that this animal provides a suitable model for further examination of the characteristics of renal reabsorption and excretion of bicarbonate during immaturity. Titrations of bicarbonate performed in the usual manner demonstrated a threshold of 17–20 mmoles/liter, with a mean of 18.3. In the absence of significant volume expansion, maximal rates of reabsorption of bicarbonate were not observed despite filtered loads that were double those at threshold. Fractional excretion of sodium during control periods in animals which were not dehydrated averaged 2.9 ± 1.8% compared with 0.16 ± 0.08% in animals which were slightly dehydrated by their previous treatment with ammonium chloride. In this group, by replacement of gastric fluid (primarily sodium and potassium chloride) with a solution of sodium and potassium bicarbonate, renal handling of bicarbonate at varying filtered loads could be studied in the absence of volume expansion and with the continued stimulus for reabsorption of sodium. Under these circumstances, the renal threshold for bicarbonate was found to be markedly increased (25.2 ± 1.12). Saline was administered to two animals after the threshold had been passed. At any given level of filtered load the rate of excretion of bicarbonate in urine after administration of saline greatly exceeded the rate of excretion during gastric suction. The data in the present study thus indicate that the decreased threshold for bicarbonate in the young animal is not due to a limitation in intrinsic capacity for reabsorption of bicarbonate, inasmuch as capacity could be increased markedly under the stimulus
Memory T lymphocytes

Immunological memory protects organisms from recurrent challenge by pathogens. The persistence of a heightened reactive state initiated by antigenic challenge is mediated by long-lived memory lymphocytes. The survival of memory T cells is thought to require stimulation through the T cell receptor (TCR), sometimes by persistent antigen. However, memory T cells can survive in the absence of antigen, in which case TCR stimulation provided by cell surface self-peptide/major histocompatibility complex (MHC) molecules and cytokines are required to sustain memory T cells. Recent work using mouse models has provided insights into the origin of memory T cells. Understanding the mechanisms that underlie the differentiation and persistence of memory T cells may improve the effectiveness of vaccines through the induction of T cell memory.
Environmental Gradients Affect Rainbow Trout Populations among Lakes and Reservoirs in Wyoming

Abstract We defined relations of environmental variables and fish community features to statistics of samples of rainbow trout Oncorhynchus mykiss from lakes and reservoirs in Wyoming. The mean length of rainbow trout in gill-net samples was most strongly related to physical features, including elevation, measures of water chemistry, and lake morphology. Indices of abundance and biomass of rainbow trout were related to the proportion of other fish species in gill-net samples, as well as elevation, water chemistry, and lake morphology. Environmental gradients associated with changes in elevation appeared to have substantial influence on the population structure and abundance of rainbow trout in lakes and reservoirs in Wyoming.
Landmine discrimination via Bayesian adaptive multimodal processing: results for handheld and vehicular sensors

The recent development of high quality sensors paired with development of advanced statistical signal processing algorithms has shown that there are sensors that can not only discriminate targets from clutter, but can also identify subsurface or obscured targets. In a previous theoretical and simulation study, we utilized this identification capability in addition to contextual information in a multi-modal adaptive algorithm where the identification capabilities of multiple sensors are utilized to modify the prior probability density functions associated with statistical models being utilized by other sensors. We assumed that the statistics describing the features associated with each sensor modality follow a Gaussian mixture density, where in many cases the individual Gaussian distributions that make up the mixture result from different target types or target classes. We utilized identification information from one sensor to modify the weights associated with the probability density functions being utilized by algorithms associated with other sensor modalities. In our simulations, this approach is shown to be improve sensor performance by reducing the overall false alarm rate. In this talk, we transition the approach from a simulation study to consider real field data collected by both handheld and vehicular based systems. We show that by appropriate modification of our statistical models to accurately match field data, improved performance can be obtained over traditional sensor fusion algorithms.
Novel onboard sensor systems for making angular measurements on spinning projectiles

Novel sensor have been developed at the Army Research Laboratory (ARL) to provide continuous accurate angular measurements for spinning projectiles in free flight. These systems, which directly measure angular orientations, are distinct from angular rate sensor methodologies that require integration of these rates to estimate angular orientations. Also, many traditional rate sensors are expensive, voluminous and not well-suited to the high-g launch and high spin environment of many projectile-borne munitions. Recent advances in commercially-available magnetic sensors have yielded devices small enough, rugged enough, and/or sensitive enough to be used in body-fixed sensor constellations to make high-speed, high-resolution measurements of attitude and roll rate relative to earth's magnetic field. The addition of a complimentary sensor system measuring orientation relative to another distinct earth-fixed field of known orientation provides the information required to mathematically determine the absolute angular orientation of a spinning body within any desired navigation system, e.g., north, east, and vertical. Such a dual-field measurement system has been implemented utilizing a unique constellation of magnetoresistive sensors and ARL Solar Likeness Indicating Transducers (SLIT) to determine angular orientation with respect to the magnetic and solar fields respectively. The mathematical foundations of this dual-field sensor system will be summarized and flight experiments of the prototype systems will be discussed.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Respiratory gas exchange by the avian embryo

Abstract The mechanism of gas exchange by an avian embryo is discussed in terms of the embryo's changing metabolic rate, a constant egg shell gas permeability and the changing gas tensions inside the shell. Since gas transport across the shell is by diffusion, equations are developed which predict the gas composition in the air cell of the egg as well as the rate of exchange of O2 CO2 and water vapor. PO2 and PCO2 values were obtained from the air cells of chick embryos of various ages, and when these results are considered together with metabolic rate and measured egg shell permeability data they are found to be consistent with the hypothesis that gas exchange by the avian embryo is limited by diffusion through its porous shell. The implications of this are discussed in terms of water vapor loss from the egg during incubation, development of the embryo's blood buffer system and the importance of the permeability of the egg shell to embryo survival.
Superadiabatic Combustion in Conducting Tubes and Heat Exchangers of Finite Length

Classic theories of combustion rely upon the principle that the maximum temperature attainable in a reaction is predicted by the adiabatic equilibrium temperature. In certain burner configurations, however, the maximum temperature may locally exceed this value by a significant amount due to heat recirculation, which has led to the concept of superadiabatic combustion. A striking aspect of this type of combustion is a broadening of the limits of flammability due to the accelerating effect of temperature increases on chemical reaction rates. In this paper, a simple analytical model is developed to study the superadiabatic performance of a combustor consisting of two parallel channels of finite length that are divided by a conducting wall. Assuming equal flow rates in the individual channels, the co-flow configuration is equivalent to combustion in conducting tubes, whereas the counterflow configuration is conceptually similar to a Swiss-roll burner. In both cases, the characteristics of superadiabatic combustion of a fuel-rich premixed fuel/air mixture are studied in terms of wall conductivity, heat transfer, and geometry of the combustor.
Rapid aqueous sample extraction of VOCs: effect of physical parameters.

Abstract Rapid aqueous sample extraction (RASE) devices were constructed and characterized using m-xylene as a test analyte. Extraction of m-xylene from aqueous samples was studied under many different conditions, independently varying extractor volume, extraction gas flow rate, temperature, pressure, sample volume, and sample concentration. Gas samples were analyzed as controls to determine the non-extraction (transport) component of the analyte pulse width. The extraction of analyte from water to the gas phase took proportionately longer (compared to transport) for RASE apparatus that had a volume greater than 10 ml. An order of magnitude change in RASE volume resulted in larger than an order of magnitude change in extraction time and total analyte pulse width. The flow rate of the extraction gas had a much larger effect on a RASE apparatus with a volume greater than 10 ml. For these large extractors, both extraction time and total analyte pulse width decreased by a factor of 4 for a flow increase from 40 to 120 ml min−1. There was little change at higher flow rates, or for extractors with smaller volumes. Temperatures below 40 °C resulted in large increases in the pulse duration due to broadening during transport. The temperature effect on extraction time was only a factor of 2 over a range from 25 to 85 °C. Pressure also had only a relatively small effect, increasing extraction time and total pulse width by a factor of 2 over a range from 12 to 34 PSI. There was no observed change in either extraction time or total pulse width when the sample volume injected varied from 10 to 1000 μl, or over a concentration range from 170 to 17 000 μg l−1. RASE apparatus were capable of complete extraction of analyte from water in less than 5 s under optimized conditions.
Subcellular distribution of oxidative enzymes in human, inflamed and dilantin hyperplastic gingiva

Abstract The subcellular distribution of cytochrome oxidase (mitochondrial), NADH cytochrome c reductase (nuclei, mitochondrial, microsomal, soluble) and NADPH cytochrome c reductase (microsomal, soluble) marker activities were analysed biochemically in human inflamed and dilantin hyperplastic gingiva. Protein and enzyme distribution patterns were found to be similar in the inflamed and dilantin hyperplastic gingival subcellular fractions. Cytochrome oxidase was found primarily within the mitochondrial fraction, and NADPH cytochrome c reductase was found chiefly within the soluble fraction. NADH cytochrome c reductase distributed in each subcellular fraction, and was found within the nuclear, mitochondrial, microsomal and soluble fractions. Significantly greater activity (cytochrome oxidase, NADH cytochrome c reductase and NADPH cytochrome c reductase) was noted in mildly inflamed dilantin hyperplastic tissue than was observed in mildly to moderately inflamed gingiva. NADH cytochrome c reductase (mitochondrial) was significantly greater than cytochrome oxidase in both tissue fractions, and was rotenone, amytal and antimycin a , insensitive which suggests that the activity may be primarily associated with the outer mitochondrial membrane. The increased specific activities of the enzyme markers in dilantin gingiva may reflect metabolic activity associated with cell mitosis, proliferation, protein (collagen) synthesis and drug detoxification.
High school students' attitudes about firearms policies.

Abstract Purpose To examine high school students' attitudes about firearm policies and to compare their attitudes with those of adults. Methods The Hamilton Youth and Guns Poll is the first national survey of high school students about their attitudes concerning firearm policies. Questions were asked of 1005 sophomores, juniors, and seniors about their actual (i.e., direct) exposure (e.g., presence of a gun in the home) and about their social (i.e., indirect) exposure (e.g., whether the student could get a gun) to firearms and related violence. Population weights were applied, and multivariate logistic regression was used to examine the relationship between demographic and exposure variables and opinions about firearm policies. Results Most high school students supported more restrictive firearm policies. Opinions varied little by demographic variables with the exception of gender. Females were significantly more supportive of most firearm policies. Actual exposure was a more consistent predictor than social exposure. Students living in a home with a gun, particularly a handgun, were less likely to support most restrictive gun policies. Conclusions Most high school students in the United States favor stringent policies governing firearms. Adolescents' attitudes about firearm policies parallel those of adults.
A facile synthesis of vinyl and allylic 2,2,2-trifluoroethyl phosphonates

Condensation of several representative aldehydes with the anion derived from tetrakis(2,2,2-trifluoroethyl) methylenediphosphonate, a new Wadsworth-Emmons reagent, afforded (Z)-vinyl phosphonates in good yields. The latter, when treated with a catalytic amount of potassium tert-butoxide in DMSO isomerized to the corresponding (E)-allylic phosphonates, which produce E,Z-dienes when reacted with a second aldehyde.
Nanofaceted C/Re(1121): fabrication, structure, and template for synthesizing nanostructured model Pt electrocatalyst for hydrogen evolution reaction.

We report the first observation of carbon-induced nanofaceting of a Re single crystal and its application in synthesizing a nanostructured model Pt electrocatalyst investigated using multiple surface science techniques, including low-energy electron diffraction, Auger electron spectroscopy, X-ray photoelectron spectroscopy, low-energy ion scattering, and scanning tunneling microscopy, combined with electrochemical reaction measurements. Upon annealing in acetylene at 700 K followed by annealing in vacuum at 1100 K, an initially planar Re(1121) surface becomes completely faceted and covered with three-sided nanopyramids exposing (0111), (1011), and (1120) faces. Using the faceted C/Re(1121) surface as a template, we have successfully fabricated a nanostructured Pt monolayer (ML) electrocatalyst. The Pt ML supported on the C/Re nanotemplate exhibits higher activity for the hydrogen evolution reaction than Pt(111). This is the first application of faceted metal surfaces as templates for synthesis of nan...
Applying Technology to Inquiry-Based Learning in Early Childhood Education

Children naturally explore and learn about their environments through inquiry, and computer technologies offer an accessible vehicle for extending the domain and range of this inquiry. Over the past decade, a growing number of interactive games and educational software packages have been implemented in early childhood education and addressed a variety of subjects, including mathematics, science, reading, language, and social studies. However, most software packages have yet to integrate technology into inquiry-based learning for early childhood contexts. Based on existing theoretical frameworks, we suggest that instructional technologies should be used in early childhood inquiry education to (a) enrich and provide structure for problem contexts, (b) facilitate resource utilization, and (c) support cognitive and metacognitive processes. Examples of existing and hypothetical early childhood applications are provided as we elaborate on each role. Challenges and future research directions are also identified and discussed.
Multistage design procedures for identifying two-factor interactions, when higher effects are negligible

Abstract Consider a 2m factorial experiment. Let L(ν×1) be the vector of factorial effects which are nonnegligible. Let μ denote the general mean. It will always be assumed that μ∈L, even though in some situations μ may be zero. All factorial effects which are not in L are thus assumed zero. We do not know what parameters are elements of L, and furthermore, we do not know the value of the various elements of L. The problem of model identification is to determine the elements of L, and also estimate the same. In this paper we shall investigate this problem in a certain limited context. We shall assume that all elements of L are included in the vector of parameters L ∗ (ν ∗ ×1) , except possibly for a set of p parameters. In this paper we shall take L ∗ to consist of the set of main effects, and the general mean μ. We assume p to be small and L to contain possibly a set of p 2-factor interactions. Three-factor and higher interactions are assumed negligible. We start with a saturated resolution III design of the 2m−q type, where m=2k−1. For a given value of (m−q) we shall also consider values of m smaller than the maximum. The purpose of the experiment is to estimate μ and the main effects, and furthermore identify all the p two-factor interactions which are nonnegligible, and also estimate the same. For this purpose, we consider using a multistage design, i.e., a design which allows the experiment to be done in several parts or stages. In the first stage, the resolution three design plus possibly a few extra treatments may be used. After looking at the resulting data, a further set of treatments is selected and observed. This may resolve the problem. If the problem is still not resolved we continue the same way, that is, we take a few more treatments and see if we can resolve the problem. The attempt is to have a design in which the average sample number is as small as possible. Examples are given for k=3,4.
A new approach to analyticity of Dirichlet{Neumann operators

This paper outlines the theoretical background of a new approach towards an accurate and well-conditioned perturbative calculation of Dirichlet{Neumann operators (DNOs) on domains that are perturbations of simple geometries. Previous work on the analyticity of DNOs has produced formulae that, as we have found, are very ill-conditioned. We show how a simple change of variables can lead to recursions that satisfy analyticity estimates without relying on subtle cancellation properties at the heart of previous formulae.
Permeability of the peritrophic membrane of the Douglas fir tussock moth (Orgyia pseudotsugata)

Abstract 1. 1. The peritrophic membrane of the Douglas fir tussock moth, Orygia pseudotsugata, is permeable to molecules and particulates up to the size of ⩾300 2. 2. Microorganisms the size of Bacillus thuringiensis and its spores cannot penetrate the intact peritrophic membrane. The pores exist which would allow penetration of such entities as non-occluded virus, enveloped nucleocapids of such microorganisms as Orygia pseudotsugata nuclear polyhedrosis virus, and small bacteria. 3. 3. The dissociated entomocidal parasporal crystal of B. thuringiensis and the protease ficin were also tested for possible effects on the peritrophic membrane permeability. Although ficin increases permeability, the presence of 1 and 10 mg/ml crystal protein did not effect permeability of the membrane.
A kinship-based modification of the armitage trend test to address hidden population structure and small differential genotyping errors.

Background/Aims We propose a modification of the well-known Armitage trend test to address the problems associated with hidden population structure and hidden relatedness in genome-wide case-control association studies. Methods The new test adopts beneficial traits from three existing testing strategies: the principal components, mixed model, and genomic control while avoiding some of their disadvantageous characteristics, such as the tendency of the principal components method to over-correct in certain situations or the failure of the genomic control approach to reorder the adjusted tests based on their degree of alignment with the underlying hidden structure. The new procedure is based on Gauss-Markov estimators derived from a straightforward linear model with an imposed variance structure proportional to an empirical relatedness matrix. Lastly, conceptual and analytical similarities to and distinctions from other approaches are emphasized throughout. Results Our simulations show that the power performance of the proposed test is quite promising compared to the considered competing strategies. The power gains are especially large when small differential differences between cases and controls are present; a likely scenario when public controls are used in multiple studies. Conclusion The proposed modified approach attains high power more consistently than that of the existing commonly implemented tests. Its performance improvement is most apparent when small but detectable systematic differences between cases and controls exist.
Effects of chronic gamma radiation on the composition of the herb community of an oak-pine forest*

A complete inventory of the herb populations of the inner 50 m of the Brookhaven irradiated forest was made in 1968 and 1973. The data are compared with those of earlier inventories, giving information on changes through a ten-year period in a community exposed to chronic radiation stress. Per cent cover of Carex pensyluanica, which dominates the zone 20–40 m from the source (125-25 R/day in 1973), increased rapidly at first and then more slowly through 1968, then declined somewhat by 1973. There was no shift in its distribution over ten years. Sharp increase in Rubus spp. cover in this zone contributed to the most recent Carex decline. A greater than eight-fold rise in total density of species other than Carex occurred since 1968, mostly due to a large increase in density of important species, while only those of infrequent occurrence declined or disappeared by 1973. Rate of change in herb populations was slowed by high exposures close to the source and by competition with Carex and Rubus in the sedge zone. The distribution of Rumex acetosella changed in a manner suggesting possible genetic alteration of radiosensitivity. There was a net increase of four species between 1968 and 1973. Species diversity increased with distance from the source, increased with time from 1968 to 1973 in the outer 40–50 m zone, and changed relatively slowly with time in the inner zones of higher exposure rates. The reasons for the comparatively slow rates of successional change are discussed. We predict that with future reduction in radiation stress due to source decay and with continuing expansion of Rubus spp. clones, Carex dominance will continue to decline as species diversity and herb population densities increase slowly.
Measurement and Prediction of Vapor−Liquid Equilibrium of Aqueous 1-Ethyl-3-methylimidazolium-Based Ionic Liquid Systems

Isothermal vapor−liquid equilibria were determined for two binary ionic liquid + water systems, from 323.3 to 368.2 K, and water mole fractions greater than 0.5. The ionic liquids used were 1-ethyl-3-methylimidazolium trifluoromethanesulfonate and 1-ethyl-3-methylimidazolium trifluoroacetate. In addition, predictive thermodynamic modeling of the vapor−liquid equilibrium was performed by correlating the nonrandom two-liquid,(39) universal quasi-chemical,(40) and electrolyte-NRTL(41) models to previously measured excess enthalpy and infinite dilution activity coefficient data from the literature. For each of the systems studied at least two of the models provided adequate predictions of vapor pressure and water activity coefficients. The good predictions of vapor−liquid equilibria by these common activity coefficient models lead us to favor excess enthalpy and infinite dilution activity coefficient data over vapor−liquid equilibria data, since predictions of excess enthalpies from vapor−liquid equilibria ar...
Plant SMU-1 and SMU-2 Homologues Regulate Pre-mRNA Splicing and Multiple Aspects of Development

In eukaryotes, alternative splicing of pre-mRNAs contributes significantly to the proper expression of the genome. However, the functions of many auxiliary spliceosomal proteins are still unknown. Here, we functionally characterized plant homologues of nematode suppressors of mec-8 and unc-52 (smu). We compared transcript profiles of maize (Zea mays) smu2 endosperm with those of wild-type plants and identified pre-mRNA splicing events that depend on the maize SMU2 protein. Consistent with a conserved role of plant SMU-2 homologues, Arabidopsis (Arabidopsis thaliana) smu2 mutants also show altered splicing of similar target pre-mRNAs. The Atsmu2 mutants occasionally show developmental phenotypes, including abnormal cotyledon numbers and higher seed weights. We identified AtSMU1 as one of the SMU2-interacting proteins, and Atsmu1 mutations cause similar developmental phenotypes with higher penetrance than Atsmu2. The AtSMU2 and AtSMU1 proteins are localized to the nucleus and highly prevalent in actively dividing tissues. Taken together, our data indicated that the plant SMU-1 and SMU-2 homologues appear to be involved in splicing of specific pre-mRNAs that affect multiple aspects of development.
Effective Range Analysis of s -Wave K − p Reactions

An effective range analysis of $s$-wave ${K}^{\ensuremath{-}}p$ reaction data is carried out. Two specific problems are investigated. First, a survey is made of solutions which, in addition to fitting the above threshold data, yield a $\ensuremath{\pi}\ensuremath{\Lambda}$ resonance having the characteristics of the ${{Y}_{1}}^{*}$. The only acceptable solutions found were for even $K\ensuremath{\Sigma}N$ parity and did not lead to a ${{Y}_{0}}^{*}$ resonance. Other features of these solutions are discussed, as well as the validity and applicability of the effective range approximation to describe the energy dependence of the $\overline{K}N$ data. Second, using the (nonperturbative) uncoupled phase procedure developed in the preceding paper, we investigate effective range solutions for the above threshold ${K}^{\ensuremath{-}}p$ data which, in the absence of influence of the $\overline{K}N$ channel, would have the pion-hyperon scattering amplitudes predicted by global symmetry of the pion-baryon interaction. The concept of global symmetry is found to be compatible with the present ${K}^{\ensuremath{-}}p$ data. The actual $\ensuremath{\pi}Y$ phases, however, are quite different from the global symmetry uncoupled phases in states coupled to the $\overline{K}N$ $s$ wave, and there are solutions in which the ${{Y}_{0}}^{*}$ arises as a quasi-bound state resonance. Going beyond the physical predictions of these surveys, we conclude that there are at present almost enough $\overline{K}N$ data above threshold to justify a search for effective range solutions (then predicting whether either ${{Y}_{1}}^{*}$ or ${{Y}_{0}}^{*}$ is in the same partial wave as a $\overline{K}N$ $s$ state). Moreover, it is clear that such solutions will be quite different from the results of a constant scattering-length analysis of low-energy data.
EFFECT OF MATERNAL WEIGHT ON POSTTERM DELIVERY

Examine the effect of prepregnancy weight and maternal gestational weight gain on postterm delivery rates. This was a retrospective cohort study of term, singleton births (N=375 003). We performed multivariable analyses of the association between postterm pregnancy and both prepregnancy body mass index (BMI) and maternal weight gain. Prolonged or postterm delivery (41 or 42 weeks) was increasingly common with increasing prepregnancy weight (P<0.001) and increasing maternal weight gain (P<0.001). Underweight women were 10% less likely to deliver postterm than normal weight women who gain within the recommendations (adjusted odds ratio 0.90 (95% confidence interval 0.83, 0.97)). Overweight women who gain within or above recommendations were also at increased risk of a 41-week delivery. Finally, obese women were at increased risk of a 41-week delivery with increasing risk with increasing weight (below, within and above recommendations adjusted odds ratios 1.19, 1.21, and 1.27, respectively). Elevated prepregnancy weight and maternal weight gain both increase the risk of a postterm delivery. Although most women do not receive preconceptional care, restricting weight gain to the within the recommended range can reduce the risk of postterm pregnancy in normal, overweight and obese women.