Showing papers by "Michigan State University published in 2000"

Meta-analysis of observational studies in epidemiology - A proposal for reporting

Abstract: ObjectiveBecause of the pressure for timely, informed decisions in public health and clinical practice and the explosion of information in the scientific literature, research results must be synthesized. Meta-analyses are increasingly used to address this problem, and they often evaluate observational studies. A workshop was held in Atlanta, Ga, in April 1997, to examine the reporting of meta-analyses of observational studies and to make recommendations to aid authors, reviewers, editors, and readers.ParticipantsTwenty-seven participants were selected by a steering committee, based on expertise in clinical practice, trials, statistics, epidemiology, social sciences, and biomedical editing. Deliberations of the workshop were open to other interested scientists. Funding for this activity was provided by the Centers for Disease Control and Prevention.EvidenceWe conducted a systematic review of the published literature on the conduct and reporting of meta-analyses in observational studies using MEDLINE, Educational Research Information Center (ERIC), PsycLIT, and the Current Index to Statistics. We also examined reference lists of the 32 studies retrieved and contacted experts in the field. Participants were assigned to small-group discussions on the subjects of bias, searching and abstracting, heterogeneity, study categorization, and statistical methods.Consensus ProcessFrom the material presented at the workshop, the authors developed a checklist summarizing recommendations for reporting meta-analyses of observational studies. The checklist and supporting evidence were circulated to all conference attendees and additional experts. All suggestions for revisions were addressed.ConclusionsThe proposed checklist contains specifications for reporting of meta-analyses of observational studies in epidemiology, including background, search strategy, methods, results, discussion, and conclusion. Use of the checklist should improve the usefulness of meta-analyses for authors, reviewers, editors, readers, and decision makers. An evaluation plan is suggested and research areas are explored.

Statistical pattern recognition: a review

Abstract: The primary goal of pattern recognition is supervised or unsupervised classification. Among the various frameworks in which pattern recognition has been traditionally formulated, the statistical approach has been most intensively studied and used in practice. More recently, neural network techniques and methods imported from statistical learning theory have been receiving increasing attention. The design of a recognition system requires careful attention to the following issues: definition of pattern classes, sensing environment, pattern representation, feature extraction and selection, cluster analysis, classifier design and learning, selection of training and test samples, and performance evaluation. In spite of almost 50 years of research and development in this field, the general problem of recognizing complex patterns with arbitrary orientation, location, and scale remains unsolved. New and emerging applications, such as data mining, web searching, retrieval of multimedia data, face recognition, and cursive handwriting recognition, require robust and efficient pattern recognition techniques. The objective of this review paper is to summarize and compare some of the well-known methods used in various stages of a pattern recognition system and identify research topics and applications which are at the forefront of this exciting and challenging field.

New Trends in Measuring Environmental Attitudes: Measuring Endorsement of the New Ecological Paradigm: A Revised NEP Scale

Abstract: Dunlap and Van Liere's New Environmental Paradigm (NEP) Scale, published in 1978, has become a widely used measure of proenvironmental orientation. This article develops a revised NEP Scale designed to improve upon the original one in several respects: (1) It taps a wider range of facets of an ecological worldview, (2) It offers a balanced set of pro- and anti-NEP items, and (3) It avoids outmoded terminology. The new scale, termed the New Ecological Paradigm Scale, consists of 15 items. Results of a 1990 Washington State survey suggest that the items can be treated as an internally consistent summated ratingscale and also indicate a modest growth in pro-NEP responses among Washington residents over the 14 years since the original study.

What Do New Views of Knowledge and Thinking Have to Say About Research on Teacher Learning

Abstract: The education and research communities are abuzz with new (or at least re-discovered) ideas about the nature of cognition and learning. Terms like \"situated cognition,\" \"distributed cognition,\" and \"communities of practice\" fill the air. Recent dialogue in Educational Researcher (Anderson, Reder, & Simon, 1996,1997; Greeno, 1997) typifies this discussion. Some have argued that the shifts in world view that these discussions represent are even more fundamental than the now-historical shift from behaviorist to cognitive views of learning (Shuell, 1986). These new ideas about the nature of knowledge, thinking, and learning—which are becoming known as the \"situative perspective\" (Greeno, 1997; Greeno, Collins, & Resnick, 1996)—are interacting with, and sometimes fueling, current reform movements in education. Most discussions of these ideas and their implications for educational practice have been cast primarily in terms of students. Scholars and policymakers have considered, for example, how to help students develop deep understandings of subject matter, situate students' learning in meaningful contexts, and create learning communities in which teachers and students engage in rich discourse about important ideas (e.g., National Council of Teachers of Mathematics, 1989; National Education Goals Panel, 1991; National Research Council, 1993).

Unusually High Thermal Conductivity of Carbon Nanotubes

Abstract: Recently discovered carbon nanotubes have exhibited many unique material properties including very high thermal conductivity. Strong sp 2 bonding configurations in carbon network and nearly perfect self-supporting atomic structure in nanotubes give unusually high phonon-dominated thermal conductivity along the tube axis, possibly even surpassing that of other carbon-based materials such as diamond and graphite (in plane). In this chapter, we explore theoretical and experimental investigations for the thermal-transport properties of these materials.

Cyclooxygenases: Structural, cellular, and molecular biology

Abstract: ▪ Abstract The prostaglandin endoperoxide H synthases-1 and 2 (PGHS-1 and PGHS-2; also cyclooxygenases-1 and 2, COX-1 and COX-2) catalyze the committed step in prostaglandin synthesis. PGHS-1 and 2 are of particular interest because they are the major targets of nonsteroidal anti-inflammatory drugs (NSAIDs) including aspirin, ibuprofen, and the new COX-2 inhibitors. Inhibition of the PGHSs with NSAIDs acutely reduces inflammation, pain, and fever, and long-term use of these drugs reduces fatal thrombotic events, as well as the development of colon cancer and Alzheimer's disease. In this review, we examine how the structures of these enzymes relate mechanistically to cyclooxygenase and peroxidase catalysis, and how differences in the structure of PGHS-2 confer on this isozyme differential sensitivity to COX-2 inhibitors. We further examine the evidence for independent signaling by PGHS-1 and PGHS-2, and the complex mechanisms for regulation of PGHS-2 gene expression.

Habitat Management to Conserve Natural Enemies of Arthropod Pests in Agriculture

Abstract: ▪ Abstract Many agroecosystems are unfavorable environments for natural enemies due to high levels of disturbance. Habitat management, a form of conservation biological control, is an ecologically based approach aimed at favoring natural enemies and enhancing biological control in agricultural systems. The goal of habitat management is to create a suitable ecological infrastructure within the agricultural landscape to provide resources such as food for adult natural enemies, alternative prey or hosts, and shelter from adverse conditions. These resources must be integrated into the landscape in a way that is spatially and temporally favorable to natural enemies and practical for producers to implement. The rapidly expanding literature on habitat management is reviewed with attention to practices for favoring predators and parasitoids, implementation of habitat management, and the contributions of modeling and ecological theory to this developing area of conservation biological control. The potential to int...

A Meta-Analysis of Fear Appeals: Implications for Effective Public Health Campaigns

Abstract: The fear appeal literature is examined in a comprehensive synthesis using meta-analytical techniques. The meta-analysis suggests that strong fear appeals produce high levels of perceived severity and susceptibility, and are more persuasive than low or weak fear appeals. The results also indicate that fear appeals motivate adaptive danger control actions such as message acceptance and maladaptive fear control actions such as defensive avoidance or reactance. It appears that strong fear appeals and high-efficacy messages produce the greatest behavior change, whereas strong fear appeals with low-efficacy messages produce the greatest levels of defensive responses. Future directions and practical implications are provided.

A Comparison of Etanercept and Methotrexate in Patients with Early Rheumatoid Arthritis

Abstract: Background Etanercept, which blocks the action of tumor necrosis factor, reduces disease activity in patients with long-standing rheumatoid arthritis. Its efficacy in reducing disease activity and preventing joint damage in patients with active early rheumatoid arthritis is unknown. Methods We treated 632 patients with early rheumatoid arthritis with either twice-weekly subcutaneous etanercept (10 or 25 mg) or weekly oral methotrexate (mean, 19 mg per week) for 12 months. Clinical response was defined as the percent improvement in disease activity according to the criteria of the American College of Rheumatology. Bone erosion and joint-space narrowing were measured radiographically and scored with use of the Sharp scale. On this scale, an increase of 1 point represents one new erosion or minimal narrowing. Results As compared with patients who received methotrexate, patients who received the 25-mg dose of etanercept had a more rapid rate of improvement, with significantly more patients having 20 percent, ...

On inhibition/disinhibition in developmental psychopathology: Views from cognitive and personality psychology and a working inhibition taxonomy.

Abstract: Disinhibition is a common focus in psychopathology research. However, use of inhibition models often is piecemeal, lacking an overarching taxonomy of inhibitory processes. The author organizes key concepts and models pertaining to different kinds of inhibitory control from the cognitive and temperament/personality literatures. Within the rubrics of executive inhibitory processes, motivational inhibitory processes, and automatic attentional inhibition processes, 8 kinds of inhibition are distinguished. Three basic temperament traits may address key executive and motivational inhibitory processes. Future developmental psychopathology research should be based on a systematic conceptual taxonomy of the kinds of inhibitory function relevant to a given disorder. Such an approach can clarify which inhibition distinctions are correct and which inhibition deficits go with which disorders.

Ethylene: a gaseous signal molecule in plants.

Abstract: ▪ Abstract Ethylene regulates a multitude of plant processes, ranging from seed germination to organ senescence. Of particular economic importance is the role of ethylene as an inducer of fruit rip...

Greenhouse gases in intensive agriculture: contributions of individual gases to the radiative forcing of the atmosphere.

Abstract: Agriculture plays a major role in the global fluxes of the greenhouse gases carbon dioxide, nitrous oxide, and methane. From 1991 to 1999, we measured gas fluxes and other sources of global warming potential (GWP) in cropped and nearby unmanaged ecosystems. Net GWP (grams of carbon dioxide equivalents per square meter per year) ranged from 110 in our conventional tillage systems to -211 in early successional communities. None of the annual cropping systems provided net mitigation, although soil carbon accumulation in no-till systems came closest to mitigating all other sources of GWP. In all but one ecosystem, nitrous oxide production was the single greatest source of GWP. In the late successional system, GWP was neutral because of significant methane oxidation. These results suggest additional opportunities for lessening the GWP of agronomic systems.

From Micro to Meso: Critical Steps in Conceptualizing and Conducting Multilevel Research

Abstract: Although interest in multilevel organizational theory, research, and methods has been on the rise in recent years, vigorous debates in the literature regarding appropriate ways to conceptualize and...

Global QCD analysis of parton structure of the nucleon: CTEQ5 parton distributions

Abstract: An up-to-date global QCD analysis of high energy lepton-hadron and hadron-hadron interactions is performed to better determine the gluon and quark parton distributions in the nucleon. Improved experimental data on inclusive jet production, in conjunction with precise deep inelastic scattering data, place good constraints on the gluon over a wide range of x; while new data on asymmetries in Drell-Yan processes contribute to better determine the d/u ratio. Comparisons with results of other recent global analyses are made, and the differences are described. Open issues and the general problem of determining the uncertainties of parton distributions are discussed.

Filterbank-based fingerprint matching

Abstract: Biometrics-based verification, especially fingerprint-based identification, is receiving a lot of attention. There are two major shortcomings of the traditional approaches to fingerprint representation. For a considerable fraction of population, the representations based on explicit detection of complete ridge structures in the fingerprint are difficult to extract automatically. The widely used minutiae-based representation does not utilize a significant component of the rich discriminatory information available in the fingerprints. Local ridge structures cannot be completely characterized by minutiae. Further, minutiae-based matching has difficulty in quickly matching two fingerprint images containing a different number of unregistered minutiae points. The proposed filter-based algorithm uses a bank of Gabor filters to capture both local and global details in a fingerprint as a compact fixed length FingerCode. The fingerprint matching is based on the Euclidean distance between the two corresponding FingerCodes and hence is extremely fast. We are able to achieve a verification accuracy which is only marginally inferior to the best results of minutiae-based algorithms published in the open literature. Our system performs better than a state-of-the-art minutiae-based system when the performance requirement of the application system does not demand a very low false acceptance rate. Finally, we show that the matching performance can be improved by combining the decisions of the matchers based on complementary (minutiae-based and filter-based) fingerprint information.

Overexpression of the Arabidopsis CBF3 transcriptional activator mimics multiple biochemical changes associated with cold acclimation

Abstract: We further investigated the role of the Arabidopsis CBF regulatory genes in cold acclimation, the process whereby certain plants increase in freezing tolerance upon exposure to low temperature. The CBF genes, which are rapidly induced in response to low temperature, encode transcriptional activators that control the expression of genes containing the C-repeat/dehydration responsive element DNA regulatory element in their promoters. Constitutive expression of either CBF1 or CBF3 (also known as DREB1b and DREB1a, respectively) in transgenic Arabidopsis plants has been shown to induce the expression of target COR (cold-regulated) genes and to enhance freezing tolerance in nonacclimated plants. Here we demonstrate that overexpression of CBF3 in Arabidopsis also increases the freezing tolerance of cold-acclimated plants. Moreover, we show that it results in multiple biochemical changes associated with cold acclimation: CBF3-expressing plants had elevated levels of proline (Pro) and total soluble sugars, including sucrose, raffinose, glucose, and fructose. Plants overexpressing CBF3 also had elevated P5CS transcript levels suggesting that the increase in Pro levels resulted, at least in part, from increased expression of the key Pro biosynthetic enzyme Delta(1)-pyrroline-5-carboxylate synthase. These results lead us to propose that CBF3 integrates the activation of multiple components of the cold acclimation response.

rRNA operon copy number reflects ecological strategies of bacteria.

Abstract: Although natural selection appears to favor the elimination of gene redundancy in prokaryotes, multiple copies of each rRNA-encoding gene are common on bacterial chromosomes. Despite this conspicuous deviation from single-copy genes, no phenotype has been consistently associated with rRNA gene copy number. We found that the number of rRNA genes correlates with the rate at which phylogenetically diverse bacteria respond to resource availability. Soil bacteria that formed colonies rapidly upon exposure to a nutritionally complex medium contained an average of 5.5 copies of the small subunit rRNA gene, whereas bacteria that responded slowly contained an average of 1.4 copies. In soil microcosms pulsed with the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), indigenous populations of 2,4-D-degrading bacteria with multiple rRNA genes (x = 5.4) became dominant, whereas populations with fewer rRNA genes (x = 2.7) were favored in unamended controls. These findings demonstrate phenotypic effects associated with rRNA gene copy number that are indicative of ecological strategies influencing the structure of natural microbial communities.

Ecotoxicological Risk Assessment for Roundup ® Herbicide

Abstract: Glyphosate-based weed control products are among the most widely used broad-spectrum herbicides in the world. The herbicidal properties of glyphosate were discovered in 1970, and commercial formulations for nonselective weed control were first introduced in 1974 (Franz et al. 1997). Formulations of glyphosate, including Roundup® Herbicide (RU)1 (Monsanto Company, St. Louis, MO), have been extensively investigated for their potential to produce adverse effects in nontarget organisms. Governmental regulatory agencies, international organizations, and others have reviewed and assessed the available scientific data for glyphosate formulations and independently judged their safety. Conclusions from three major organizations are publicly available and indicate RU can be used with minimal risk to the environment (Agriculture Canada 1991; USEPA 1993a; WHO 1994). Several review publications are available on the fate and effects of RU or glyphosate in the environment (Carlisle and Trevors 1988;Smith and Oehme 1992 ; Malik et al. 1989;Rueppel et al. 1977; Sullivan and Sullivan 1997;Forestry Canada, 1989). In addition, several books have been published about the environmental and human health considerations of glyphosate and its formulations (Grossbard and Atkinson 1985; Franz et al. 1997). In addition, RU and other glyphosate formulations have been selected for use in a number of weed control programs for state and local jurisdictions in the United States. Many of these uses require that ecological risk assessments be conducted in the form of Environmental Impact Statements or Environmental Assessments. These documents are comprehensive and specific to local use situations. Documents are available for risk assessments in Texas, Washington, Oregon, Pennsylvania, New York, Virginia, and other states (USDA 1989;USDA 1992;USDA 1996;USDA 1997;USDI 1989; Washington State DOT 1993).

Dimensionality reduction using genetic algorithms

Abstract: Pattern recognition generally requires that objects be described in terms of a set of measurable features. The selection and quality of the features representing each pattern affect the success of subsequent classification. Feature extraction is the process of deriving new features from original features to reduce the cost of feature measurement, increase classifier efficiency, and allow higher accuracy. Many feature extraction techniques involve linear transformations of the original pattern vectors to new vectors of lower dimensionality. While this is useful for data visualization and classification efficiency, it does not necessarily reduce the number of features to be measured since each new feature may be a linear combination of all of the features in the original pattern vector. Here, we present a new approach to feature extraction in which feature selection and extraction and classifier training are performed simultaneously using a genetic algorithm. The genetic algorithm optimizes a feature weight vector used to scale the individual features in the original pattern vectors. A masking vector is also employed for simultaneous selection of a feature subset. We employ this technique in combination with the k nearest neighbor classification rule, and compare the results with classical feature selection and extraction techniques, including sequential floating forward feature selection, and linear discriminant analysis. We also present results for the identification of favorable water-binding sites on protein surfaces.

Biometric identification

Abstract: W A LT ER S IP SE R For this reason, more and more organizations are looking to automated identity authentication systems to improve customer satisfaction and operating efficiency as well as to save critical resources (see Figure 1). Furthermore, as people become more connected electronically, the ability to achieve a highly accurate automatic personal identification system is substantially more critical [5]. Personal identification is the process of associating a particular individual with an identity. Identification can be in the form of verification (also known as authentication), which entails authenticating a claimed identity (“Am I who I claim I am?”), or recognition (also known as identification), which entails determining the identity of a given person from a database of persons known to the system (“Who am I?”). Knowledge-based and token-based automatic personal identification approaches have been the two traditional techniques widely used [8]. Token-based approaches use something you have to make a personal identification, such as a passport, driver’s license, ID card, credit card, or keys. Knowledge-based approaches use something you know to make a personal identification, such as a password or a personal identification number (PIN). Since these traditional approaches are not based on any inherent attributes of an individual to make a personal identification, they suffer from the

CsBi4Te6: A High-Performance Thermoelectric Material for Low-Temperature Applications

Abstract: Thermoelectric (Peltier) heat pumps are capable of refrigerating solid or fluid objects, and unlike conventional vapor compressor systems, they can be miniaturized without loss of efficiency. More efficient thermoelectric materials need to be identified, especially for low-temperature applications in electronics and devices. The material CsBi(4)Te(6) has been synthesized and its properties have been studied. When doped appropriately, it exhibits a high thermoelectric figure of merit below room temperature (ZT(max) approximately 0.8 at 225 kelvin). At cryogenic temperatures, the thermoelectric properties of CsBi(4)Te(6) appear to match or exceed those of Bi(2-x)Sb(x)Te(3-y)Se(y) alloys.

Big houses, big cars, superfleas and the costs of reproduction

Abstract: The assumption of costs of reproduction were a logical necessity for much of the early development of life history theory. An unfortunate property of 'logical necessities' is that it is easy to also assume that they must be true. What if this does not turn out to be the case? The existence and universality of costs of reproduction were initially challenged with empirical data of questionable value, but later with increasingly strong theoretical and empirical results. Here, we discuss Ken Spitze's 'superfleas', which represent what we consider to be the strongest empirical challenge to the universality of costs, then offer a possible explanation for their existence.

Team Structure and Performance: Assessing the Mediating Role of Intrateam Process and the Moderating Role of Task Type

Abstract: The authors used data from 45 production teams (626 individuals) and their supervisors to test hypotheses related to team structure. For teams engaged primarily in conceptual tasks, interdependence...

Annual fluxes of carbon from deforestation and regrowth in the Brazilian Amazon

Abstract: The distribution of sources and sinks of carbon among the world's ecosystems is uncertain Some analyses show northern mid-latitude lands to be a large sink, whereas the tropics are a net source; other analyses show the tropics to be nearly neutral, whereas northern mid-latitudes are a small sink Here we show that the annual flux of carbon from deforestation and abandonment of agricultural lands in the Brazilian Amazon was a source of about 02 Pg Cyr(-1) over the period 1989-1998 (1 Pg is 10(15) g) This estimate is based on annual rates of deforestation and spatially detailed estimates of deforestation, regrowing forests and biomass Logging may add another 5-10% to this estimate, and fires may double the magnitude of the source in years following a drought The annual source of carbon from land-use change and fire approximately offsets the sink calculated for natural ecosystems in the region Thus this large area of tropical forest is nearly balanced with respect to carbon, but has an interannual variability of +/- 02 PgC yr(-1)

Kinematics of Metal-poor Stars in the Galaxy. III. Formation of the Stellar Halo and Thick Disk as Revealed from a Large Sample of Nonkinematically Selected Stars

Abstract: We present a detailed analysis of the space motions of 1203 solar-neighborhood stars with metal abundances [Fe/H] ≤ -0.6, on the basis of a catalog, of metal-poor stars selected without kinematic bias recently revised and supplemented by Beers et al. This sample, having available proper motions, radial velocities, and distance estimates for stars with a wide range of metal abundances, is by far the largest such catalog to be assembled to date. We show that the stars in our sample with [Fe/H] ≤-2.2, which likely represent a pure halo component, are characterized by a radially elongated velocity ellipsoid (σU, σV, σW) = (141 ± 11, 106 ± 9, 94 ± 8) km s-1 and small prograde rotation V = 30 to 50 km s-1, consistent with previous analysis of this sample by Beers and Sommer-Larsen based on radial velocity information alone. In contrast to the previous analysis, we find a decrease in V with increasing distance from the Galactic plane for stars that are likely to be members of the halo population (ΔV/Δ|Z| = -52 ± 6 km s-1 kpc-1), which may represent the signature of a dissipatively formed flattened inner halo. Unlike essentially all previous kinematically selected catalogs, the metal-poor stars in our sample exhibit a diverse distribution of orbital eccentricities, e, with no apparent correlation between [Fe/H] and e. This demonstrates, clearly and convincingly, that the evidence offered in 1962 by Eggen, Lynden-Bell, & Sandage for a rapid collapse of the Galaxy, an apparent correlation between the orbital eccentricity of halo stars with metallicity, is basically the result of their proper-motion selection bias. However, even in our nonkinematically selected sample, we have identified a small concentration of high-e stars at [Fe/H] ~ -1.7, which may originate, in part, from infalling gas during the early formation of the Galaxy. We find no evidence for an additional thick disk component for stellar abundances [Fe/H] ≤ -2.2. The kinematics of the intermediate-abundance stars close to the Galactic plane are, in part, affected by the presence of a rapidly rotating thick disk component with V 200 km s-1 (with a vertical velocity gradient on the order of ΔV/Δ|Z| = -30 ± 3 km s-1 kpc-1) and velocity ellipsoid (σU, σV, σW) = (46 ± 4, 50 ± 4, 35 ± 3) km s-1. The fraction of low-metallicity stars in the solar neighborhood that are members of the thick disk population is estimated as ~10% for -2.2 < [Fe/H] ≤ -1.7 and ~30% for -1.7 < [Fe/H] ≤ -1. We obtain an estimate of the radial scale length of the metal-weak thick disk of 4.5 ± 0.6 kpc. We also analyze the global kinematics of the stars constituting the halo component of the Galaxy. The outer part of the halo, which we take to be represented by local stars on orbits reaching more than 5 kpc from the Galactic plane, exhibits no systematic rotation. In particular, we show that previous suggestions of the presence of a counter-rotating high halo are not supported by our analysis. The density distribution of the outer halo is nearly spherical and exhibits a power-law profile that is accurately described as ρ ∝ R-3.55±0.13. The inner part of the halo is characterized by a prograde rotation and a highly flattened density distribution. We find no distinct boundary between the inner and outer halo. We confirm the clumping in angular-momentum phase space of a small number of local metal-poor stars noted in 1999 by Helmi et al. We also identify an additional elongated feature in angular-momentum phase space extending from the clump to regions with high azimuthal rotation. The number of members in the detected clump is not significantly increased from that reported by Helmi et al., even though the total number of the sample stars we consider is almost triple that of the previous investigation. We conclude that the fraction of halo stars that may have arisen from the precursor object of this clump may be smaller than 10% of the present Galactic halo, as previously suggested. The implications of our results for the formation of the Galaxy are discussed, in particular in the context of the currently favored cold dark matter theory of hierarchical galaxy formation.

3.6 Minutes per Day: The Scarcity of Informational Texts in First Grade.

Abstract: Although scholars have called for greater attention to informational texts in the early grades for some time, there have been few data available about the degree to which informational texts are actually included in early grade classrooms, and in what ways. This study provides basic, descriptive information about informational text experiences offered to children in 20 first-grade classrooms selected from very low- and very high-SES school districts. Each classroom was visited for four full days over the course of a school year. On each visit, data were collected about the types of texts on classroom walls and other surfaces, in the classroom library, and in classroom written language activities. Results show a scarcity of informational texts in these classroom print environments and activities—there were relatively few informational texts included in classroom libraries, little informational text on classroom walls and other surfaces, and a mean of only 3.6 minutes per day spent with informational texts during classroom written language activities. This scarcity was particularly acute for children in the low-SES school districts, where informational texts comprised a much smaller proportion of already-smaller classroom libraries, where informational texts were even less likely to be found on classroom walls and other surfaces, and where the mean time per day spent with informational texts was 1.9 minutes, with half the low-SES classrooms spending no time at all with informational texts during any of the four days each was observed. Strategies for increasing attention to informational texts in the early grades are presented. [Note: This article is reprinted in Promisng Practices for Urban Reading Instruction, www.reading.orgpublicationsbbvbooksbk518.] Si bien, desde hace algun tiempo, los investigadores han mostrado la necesidad de prestar mayor atencion a los textos informativos en los grados iniciales, se dispone de pocos datos acerca del grado en el que efectivamente se incorporan textos informativos en las aulas de grados iniciales y de la forma en que son utilizados. Este estudio proporciona informacion basica, descriptiva acerca de experiencias con textos informativos llevadas a cabo con ninos de 20 aulas de primer grado seleccionadas de distritos escolares de nivel socioeconomico (NSE) muy bajo y muy alto. Se visito cada aula durante cuatro dias completos en el curso del ano escolar. En cada visita se recogieron datos sobre los tipos de textos que aparecian en las paredes del aula y otras superficies, en la biblioteca del aula y en las actividades de lenguaje escrito. Los resultados muestran una escasez de textos informativos en las escrituras del medio y en las actividades; habia pocos textos informativos en las bibliotecas de las aulas, pocos textos informativos en las paredes del aula y otras superficies y una media de solo 3.6 minutos por dia dedicados a textos informativos durante las actividades con el lenguaje escrito. Esta escasez fue particularmente aguda en el caso de los distritos escolares de bajo NSE, en los cuales los textos informativos constituian una pequena proporcion en las ya pequenas bibliotecas de las aulas. Asimismo, era poco probable encontrar textos informativos en las paredes de las aulas y otras superficies, el tiempo promedio por dia dedicado a textos informativos fue de 1.9 minutos y en la mitad de las aulas de bajo NSE no se trabajo en ningun momento con textos informativos durante los cuatro dias de observacion. Se presentan estrategias para desarrollar la atencion hacia los textos informativos en los grados iniciales. Obgleich die Wissenschaftler seit einiger Zeit fordern, den informativen Texten grosere Beachtung in Anfangsklassen zu widmen, sind nur wenige Daten uber das Ausmas verfugbar, in welchem informative Texte tatsachlich in Anfangsklassen integriert werden und auf welche Weise dies geschieht. Diese Studie liefert grundlich dargelegte Erkenntnisse uber die Verwertung informativer Texterfahrungen, die Kinder der ersten Klasse in 20 ausgesuchten Klassenraumen von sehr niedrigen bis zu sehr hohen sozial-okonomischen {SES=SocioEconomic Status} Schulbezirken machten. Jeder Klassenraum wurde fur einen vollen Tag an insgesamt vier Tagen im Verlauf eines Schuljahres besucht. Bei jedem Besuch wurden Daten uber die Art der Texte an Klassenraumwanden und anderen Aushangflachen, in der Klassenraumbucherei und bei schriftlichen Klassenraumaktivitaten gesammelt. Die Resultate zeigen einen Mangel an informativen Texten in dieser fur Gedrucktes und ahnlicher Aktivitaten vorgesehenen Klassenraumumgebung-es fanden sich relativ wenige informative Texte einschlieslich der Klassenraumbucherei, wenig informativer Text an Klassenraumwanden und anderen Flachen, und wahrend der Sprachaktivitaten im Durchschnitt nur 3.6 mit informativen Texten verbrachte Minuten pro Tag. Diese Einschrankung war besonders bei Kindern im unteren SES-Schulbezirk akut, wo informative Texte einen noch weit geringeren Anteil bilden, bei ohnehin kleineren Klassenraumbibliotheken, wobei solche informativen Texte weit weniger an Klassenraumwanden oder anderen Flachen zu finden waren und wo im Tagesdurchschnitt 1.9 Minuten mit informativen Texten verbracht wurden, wobei die Halfte der niedrigen SES-Klassenraume uberhaupt keine Zeit an nicht einem einzigen der vier observierten Tage mit informativen Texten verbrachten. Strategien fur eine gesteigerte Bedeutung hin zu informativen Texten in den Anfangsklassen werden dargelegt. Bien que les chercheurs aient propose depuis un certain temps quelon fasse d'avantage attention aux textes informatifs pendant les premieres annees d'ecole, on dispose de peu de donnees relatives a la place qui est faite aujourd'hui aux textes informatifs dans les premieres classes et a la facon dont on les utilise cette recherche allorte une information descriptive de base sur l'experience des textes informatifs qui est offerte a des enfants de 20 classes de 1a annee issues de circonscriptions tres favorisees et tres defavorisees. On a visite chaque classe pendant une journee entiere a quatre reprises au cours d'une annee scolaire. A chaque visite, on a recueilli des donnees relatives aux types de texte se trouvant sur les murs de la classe ou d'autres supports, a la bibliotheque de la classe, et dans les activites de langue ecrite de la classe. Les resultats montrent la rarete des textes informatifs dans l'environnement ecrit de ces classes et dans leurs activitesily a il y a relativement peu de textes informatifs sur les murs de la classe ou les autres supports, et une moyenne de 3.6 minutes par jour ou des textes informatifs sont utilises au cours d'activites d'ecrit. Cette rarete est particulierement criarde pour les enfants des circonscriptions de milieu defavorise, ou les textes informatifs sont en pourcentage encore beaucoup plus petit dans bibliotheques deja plus petites, ou la probabilite de trouver des textes informatifs sur les murs de la classes ou sur d'autres supports est encore plus petite, et ou le temps moyen consacre chaque jour a des textes informatifs tombe a 1.9 minutes, tandis que la moitie de ces classes de milieu defavorise n'utilisent pas du tout de textes informatifs pendant les quatre jours ou elles ont ete observees. Nous presentons des strategies afin que l'on accorde plus d'attention aux textes informatifs.

The Relationship between Residents’ Attitudes toward Tourism and Tourism Development Options

Abstract: Many rural communities view tourism as an economic development strategy. This study explores the relationship between resident attitudes toward tourism and support for specific tourism development options. In addition, attitudes and support for development in seven diverse communities are compared. Results indicate that communities differ with respect to residents’ support for specific tourism development options and attitudes toward tourism. In general, residents perceive tourism positively and support most specific types of development. There is a relationship between attitudes and support for development, although the nature of the relationship is different for each community.