bluuebunny/crossref_metadata_2025 huggingface dataset:
The Intense Lee-Wave Rotor Event of Sierra Rotors IOP 8
Authors: Grubišić Vanda , Billings Brian J.
Published: December 2007

A large-amplitude lee-wave rotor event observationally documented during Sierra Rotors Project Intensive Observing Period (IOP) 8 on 24–26 March 2004 in the lee of the southern Sierra Nevada is examined. Mountain waves and rotors occurred over Owens Valley in a pre-cold-frontal environment. In this study, the evolution and structure of the observed and numerically simulated mountain waves and rotors during the event on 25 March, in which the horizontal circulation associated with the rotor was observed as an opposing, easterly flow by the mesonetwork of surface stations in Owens Valley, are analyzed.

The high-resolution numerical simulations of this case, performed with the Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS) run with multiple nested-grid domains, the finest grid having 333-m horizontal spacing, reproduced many of the observed features of this event. These include small-amplitude waves above the Sierra ridge decoupled from thermally forced flow within the valley, and a large-amplitude mountain wave, turbulent rotor, and strong westerlies on the Sierra Nevada lee slopes during the period of the observed surface easterly flow. The sequence of the observed and simulated events shows a pronounced diurnal variation with the maximum wave and rotor activity occurring in the early evening hours during both days of IOP 8.

The lee-wave response, and thus indirectly the appearance of lee-wave rotor during the core IOP 8 period, is found to be strongly controlled by temporal changes in the upstream ambient wind and stability profiles. The downstream mountain range exerts strong control over the lee-wave horizontal wavelength during the strongest part of this event, thus exhibiting the control over the cross-valley position of the rotor and the degree of strong downslope wind penetration into the valley.
Predictability and Error Growth Dynamics in Cloud-Resolving Models
Authors: Hohenegger Cathy , Schär Christoph
Published: December 2007

While the benefits of ensemble techniques over deterministic numerical weather predictions (NWP) are now widely recognized, the prospects of ensemble prediction systems (EPS) at high computational resolution are still largely unclear. Difficulties arise due to the poor knowledge of the mechanisms promoting rapid perturbation growth and propagation, as well as the role of nonlinearities. In this study, the dynamics associated with the growth and propagation of initial uncertainties is investigated by means of real-case high-resolution (cloud resolving) NWP integrations. The considered case is taken from the Mesoscale Alpine Programme intensive observing period 3 (MAP IOP3) and involves convection of intermediate intensity. To assess the underlying mechanisms and the degree of linearity upon the predictability of the flow, vastly different initial perturbation methodologies are compared, while all simulations use identical lateral boundary conditions to mimic a perfectly predictable synoptic-scale flow.

Comparison of the perturbation methodologies indicates that the ensuing patterns of ensemble spread converge within 11 h, irrespective of the initial perturbations employed. All methodologies pinpoint the same meso-beta-scale regions of the flow as suffering from predictability limitations. This result reveals the important role of nonlinearities. Analysis also shows that hot spots of error growth can quickly (1–2 h after initialization) develop far away from the initial perturbations. This rapid radiation of the initial uncertainties throughout the computational domain is due to both sound and gravity waves, followed by the triggering and/or growth of perturbations over regions of convective instability. The growth of the uncertainties is then limited by saturation effects, which in turn are controlled by the larger-scale atmospheric environment.

From a practical point of view, it is suggested that the combined effects of rapid propagation, sizeable amplification, and inherent nonlinearities may pose severe difficulties for the design of EPS or data assimilation techniques related to high-resolution quantitative precipitation forecasting.
Evaluating Clouds in Long-Term Cloud-Resolving Model Simulations with Observational Data
Authors: Zeng Xiping , Tao Wei-Kuo , Zhang Minghua , Peters-Lidard Christa , Lang Stephen , Simpson Joanne , Kumar Sujay , Xie Shaocheng , Eastman Joseph L. , Shie Chung-Lin , Geiger James V.
Published: December 2007

Two 20-day, continental midlatitude cases are simulated with a three-dimensional (3D) cloud-resolving model (CRM) and are compared to Atmospheric Radiation Measurement Program (ARM) data. Surface fluxes from ARM ground stations and a land data assimilation system are used to drive the CRM. This modeling evaluation shows that the model simulates precipitation well but overpredicts clouds, especially in the upper troposphere. The evaluation also shows that the ARM surface fluxes can have noticeable errors in summertime.

Theoretical analysis reveals that buoyancy damping is sensitive to spatial smoothers in two-dimensional (2D) CRMs, but not in 3D ones. With this theoretical analysis and the ARM cloud observations as background, 2D and 3D simulations are compared, showing that the 2D CRM has not only rapid fluctuations in surface precipitation but also spurious dehumidification (or a decrease in cloud amount). The present study suggests that the rapid precipitation fluctuation and spurious dehumidification be attributed to the sensitivity of buoyancy damping to dimensionality.
MODIS Observations of Ship Tracks in Summertime Stratus off the West Coast of the United States
Authors: Segrin Matthew S. , Coakley James A. , Tahnk William R.
Published: December 2007

Three years of 1-km Moderate Resolution Imaging Spectroradiometer (MODIS) observations for morning (Terra) and afternoon (Aqua) summertime marine stratus off the west coast of the United States were analyzed to determine the response of the clouds to aerosols in the plumes of underlying ships. The polluted clouds were identified in pixels with elevated 2.1-μm reflectivities and 3.7-μm radiances when compared with nearby pixels that contained unpolluted clouds. An automated routine was developed to identify which of the pixels contained clouds polluted by underlying ships and then to select unpolluted control pixels on both sides of the ship track as near as was feasible to the polluted clouds, often with a separation of as little as 1 pixel. While no requirements were placed on the cloud cover fraction within the selected pixels, to facilitate comparisons with an earlier study based on 1-km Advanced Very High Resolution Radiometer (AVHRR) imagery, the results presented here are restricted to 20-pixel segments along the ship tracks in which all of the pixels identified as polluted and all of the pixels selected as controls on both sides of the tracks were found to be overcast. The pollution caused about a 20% reduction in droplet radius in both the MODIS and the AVHRR observations. In the MODIS observations, the increase in optical depth was about 15% and statistically significant at a confidence level greater than 99.5%. These changes were much larger than the 2% and statistically negligible increases found for the AVHRR observations. Like the AVHRR observations, the MODIS observations indicated that the majority of clouds (60%) lost liquid water when polluted, but consistent with the different outcomes for the optical depths, the losses for the MODIS observations were about half the nearly 20% loss found in the AVHRR observations. Cloud altitudes were unaffected by the pollution for both the MODIS and the AVHRR observations. For both morning and afternoon clouds, those with the largest increases in albedo in response to the pollution also showed the largest increases in cloud liquid water amount. The changes in droplet radii and liquid water amounts retrieved using the MODIS observations suggested that droplet growth was suppressed in the polluted clouds and that the rate of growth from cloud base to cloud top was also reduced when compared with nearby unpolluted clouds.
On the Definition of Precipitation Efficiency
Authors: Sui Chung-Hsiung , Li Xiaofan , Yang Ming-Jen
Published: December 2007

A modified definition of precipitation efficiency (PE) is proposed based on either cloud microphysics precipitation efficiency (CMPE) or water cycling processes including water vapor and hydrometeor species [large-scale precipitation efficiency (LSPE)]. These PEs are examined based on a two-dimensional cloud-resolving simulation. The model is integrated for 21 days with the imposed large-scale vertical velocity, zonal wind, and horizontal advections obtained from the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE). It is found that the properly defined PEs include all moisture and hydrometeor sources associated with surface rainfall processes so that they range from 0% to 100%. Furthermore, the modified LSPE and CMPE are highly correlated. Their linear correlation coefficient and root-mean-squared difference are insensitive to the spatial scales of averaged data and are moderately sensitive to the time period of averaged data.
Rotor and Subrotor Dynamics in the Lee of Three-Dimensional Terrain
Authors: Doyle James D. , Durran Dale R.
Published: December 2007

The internal structure and dynamics of rotors that form in the lee of topographic ridges are explored using a series of high-resolution eddy-resolving numerical simulations. Surface friction generates a sheet of horizontal vorticity along the lee slope that is lifted aloft by the mountain lee wave at the boundary layer separation point. Parallel-shear instability breaks this vortex sheet into small intense vortices or subrotors.

The strength and evolution of the subrotors and the internal structure of the main large-scale rotor are substantially different in 2D and 3D simulations. In 2D, the subrotors are less intense and are ultimately entrained into the larger-scale rotor circulation, where they dissipate and contribute their vorticity toward the maintenance of the main rotor. In 3D, even for flow over a uniform infinitely long barrier, the subrotors are more intense, and primarily are simply swept downstream past the main rotor along the interface between that rotor and the surrounding lee wave. The average vorticity within the interior of the main rotor is much weaker and the flow is more chaotic.

When an isolated peak is added to a 3D ridge, systematic along-ridge velocity perturbations create regions of preferential vortex stretching at the leading edge of the rotor. Subrotors passing through such regions are intensified by stretching and may develop values of the ridge-parallel vorticity component well in excess of those in the parent, shear-generated vortex sheet. Because of their intensity, such subrotor circulations likely pose the greatest hazard to aviation.
Characterization of Tornado Spectral Signatures Using Higher-Order Spectra
Authors: Yu Tian-You , Wang Yadong , Shapiro Alan , Yeary Mark B. , Zrnić Dusan S. , Doviak Richard J.
Published: December 2007

Distinct tornado spectral signatures (TSSs), which are similar to white noise spectra or have bimodal features, have been observed in both simulations and real data from Doppler radars. The shape of the tornado spectrum depends on several parameters such as the range of the tornado, wind field within the storm, and the reflectivity structure. In this work, one of the higher-order spectra (HOS), termed bispectrum, is implemented to characterize TSS, in which the Doppler spectrum is considered a 1D pattern. Bispectrum has been successfully applied to pattern recognition in other fields owing to the fact that bispectrum can retain the shape information of the signal. Another parameter, termed spectral flatness, is proposed to quantify the spectrum variations. It is shown in simulation that both parameters can characterize TSS and provide information in addition to the three spectral moments. The performance of the two parameters and the spectrum width for characterizing TSS are statistically analyzed and compared for various conditions. The potential of the three parameters for improving tornado detection is further demonstrated by tornadic time series data collected by a research Weather Surveillance Radar-1988 Doppler, KOUN, operated by the National Severe Storms Laboratory.
Application of the Kano–Hamilton Multiangle Inversion Method in Clear Atmospheres
Authors: Adam Mariana , Kovalev Vladimir A. , Wold Cyle , Newton Jenny , Pahlow Markus , Hao Wei M. , Parlange Marc B.
Published: December 2007

An improved measurement methodology and a data-processing technique for multiangle data obtained with an elastic scanning lidar in clear atmospheres are introduced. Azimuthal and slope scans are combined to reduce the atmospheric heterogeneity. Vertical profiles of optical depth and intercept (proportional to the logarithm of the backscatter coefficient) are determined. The purpose of this approach is to identify and remove data points that distort the regression analysis results in order to improve the accuracy of the retrieved optical depth and of the intercept. In addition, the influence of systematic distortions has been investigated. Furthermore, profiles of the optical depth, intercept, and the range-squared-corrected signals have been used to determine the lidar overlap function as a function of range. Simulation and experimental results of this data-processing technique are presented.
Rectification of the Bias in the Wavelet Power Spectrum
Authors: Liu Yonggang , San Liang X. , Weisberg Robert H.
Published: December 2007

This paper addresses a bias problem in the estimate of wavelet power spectra for atmospheric and oceanic datasets. For a time series comprised of sine waves with the same amplitude at different frequencies the conventionally adopted wavelet method does not produce a spectrum with identical peaks, in contrast to a Fourier analysis. The wavelet power spectrum in this definition, that is, the transform coefficient squared (to within a constant factor), is equivalent to the integration of energy (in physical space) over the influence period (time scale) the series spans. Thus, a physically consistent definition of energy for the wavelet power spectrum should be the transform coefficient squared divided by the scale it associates. Such adjusted wavelet power spectrum results in a substantial improvement in the spectral estimate, allowing for a comparison of the spectral peaks across scales. The improvement is validated with an artificial time series and a real coastal sea level record. Also examined is the previous example of the wavelet analysis of the Niño-3 SST data.
Comparing Adjoint- and Ensemble-Sensitivity Analysis with Applications to Observation Targeting
Authors: Ancell Brian , Hakim Gregory J.
Published: December 2007

The sensitivity of numerical weather forecasts to small changes in initial conditions is estimated using ensemble samples of analysis and forecast errors. Ensemble sensitivity is defined here by linear regression of analysis errors onto a given forecast metric. It is shown that ensemble sensitivity is proportional to the projection of the analysis-error covariance onto the adjoint-sensitivity field. Furthermore, the ensemble-sensitivity approach proposed here involves a small calculation that is easy to implement. Ensemble- and adjoint-based sensitivity fields are compared for a representative wintertime flow pattern near the west coast of North America for a 90-member ensemble of independent initial conditions derived from an ensemble Kalman filter. The forecast metric is taken for simplicity to be the 24-h forecast of sea level pressure at a single point in western Washington State. Results show that adjoint and ensemble sensitivities are very different in terms of location, scale, and magnitude. Adjoint-sensitivity fields reveal mesoscale lower-tropospheric structures that tilt strongly upshear, whereas ensemble-sensitivity fields emphasize synoptic-scale features that tilt modestly throughout the troposphere and are associated with significant weather features at the initial time. Optimal locations for targeting can easily be determined from ensemble sensitivity, and results indicate that the primary targeting locations are located away from regions of greatest adjoint and ensemble sensitivity. It is shown that this method of targeting is similar to previous ensemble-based methods that estimate forecast-error variance reduction, but easily allows for the application of statistical confidence measures to deal with sampling error.
Lake-to-Lake Cloud Bands: Frequencies and Locations
Authors: Rodriguez Yarice , Kristovich David A. R. , Hjelmfelt Mark R.
Published: December 2007

Premodification of the atmosphere by upwind lakes is known to influence lake-effect snowstorm intensity and locations over downwind lakes. This study highlights perhaps the most visible manifestation of the link between convection over two or more of the Great Lakes lake-to-lake (L2L) cloud bands. Emphasis is placed on L2L cloud bands observed in high-resolution satellite imagery on 2 December 2003. These L2L cloud bands developed over Lake Superior and were modified as they passed over Lakes Michigan and Erie and intervening land areas. This event is put into a longer-term context through documentation of the frequency with which lake-effect and, particularly, L2L cloud bands occurred over a 5-yr time period over different areas of the Great Lakes region.
Elucidating Model Inadequacies in a Cloud Parameterization by Use of an Ensemble-Based Calibration Framework
Authors: Golaz Jean-Christophe , Larson Vincent E. , Hansen James A. , Schanen David P. , Griffin Brian M.
Published: December 2007

Every cloud parameterization contains structural model errors. The source of these errors is difficult to pinpoint because cloud parameterizations contain nonlinearities and feedbacks. To elucidate these model inadequacies, this paper uses a general-purpose ensemble parameter estimation technique. In principle, the technique is applicable to any parameterization that contains a number of adjustable coefficients. It optimizes or calibrates parameter values by attempting to match predicted fields to reference datasets. Rather than striving to find the single best set of parameter values, the output is instead an ensemble of parameter sets. This ensemble provides a wealth of information. In particular, it can help uncover model deficiencies and structural errors that might not otherwise be easily revealed. The calibration technique is applied to an existing single-column model (SCM) that parameterizes boundary layer clouds. The SCM is a higher-order turbulence closure model. It is closed using a multivariate probability density function (PDF) that represents subgrid-scale variability. Reference datasets are provided by large-eddy simulations (LES) of a variety of cloudy boundary layers. The calibration technique locates some model errors in the SCM. As a result, empirical modifications are suggested. These modifications are evaluated with independent datasets and found to lead to an overall improvement in the SCM’s performance.
Step-Mountain Technique Applied to an Atmospheric C-Grid Model, or How to Improve Precipitation near Mountains
Authors: Russell Gary L.
Published: December 2007

Starting with Arakawa and Lamb’s second-order C-grid scheme, this paper describes the modifications made to the dynamics to create a C-grid atmospheric model with a variable number of cells for each vertical column. Where mountains exist, grid cells are discarded at the bottom of the column so that the mass per square meter of retained cells is more nearly equal to that of horizontally adjacent cells. This leads to the following chain of causes and effects: decreased mass variations reduce the numerically induced alternating patterns in the horizontal velocity components, which reduce erroneous vertical mass fluxes, which reduce erroneous precipitation. In addition, horizontal flows above mountains are smoother, the Ferrel cell is stronger, and the polar cell is better organized. The C-grid performs geostrophic adjustment best among the gridpoint schemes, being the most sensitive to condensation-released heating perturbations. It also overreacts more egregiously to numerical errors, particularly with respect to the vertical mass flux, and consequently is often not used. Mesinger et al. applied the step-mountain (eta coordinate) technique to an E-grid scheme with excellent results. Its application to the C-grid reduces numerical errors in the vertical mass flux resulting in improvements in precipitation and other quantities.
An Upwind-Biased Conservative Advection Scheme for Spherical Hexagonal–Pentagonal Grids
Authors: Miura Hiroaki
Published: December 2007

A discrete form of the flux-divergence operator is developed to compute advection of tracers on spherical hexagonal–pentagonal grids. An upwind-biased advection scheme based on a piecewise linear approximation for one-dimensional regular grids is extended simply for spherical hexagonal–pentagonal grids. The distribution of a tracer over the upwind side of a cell face is linearly approximated using a nodal value and a gradient at a computational node on the upwind side. A piecewise linear approximation is relaxed to a local linear approximation, and the relaxation precludes the complicated conditional branching present in remapping schemes. Results from a cosine bell advection test show that the new scheme compares favorably with other upwind-biased schemes for spherical hexagonal–pentagonal grids.
Climatology of Warm Boundary Layer Clouds at the ARM SGP Site and Their Comparison to Models
Authors: Sengupta Manajit , Clothiaux Eugene E. , Ackerman Thomas P.
Published: December 2007

A 4-yr climatology (1997–2000) of warm boundary layer cloud properties is developed for the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) Program Southern Great Plains (SGP) site. Parameters in the climatology include cloud liquid water path, cloud-base height, and surface solar flux. These parameters are retrieved from measurements produced by a dual-channel microwave radiometer, a millimeter-wave cloud radar, a micropulse lidar, a Belfort ceilometer, shortwave radiometers, and atmospheric temperature profiles amalgamated from multiple sources, including radiosondes. While no significant interannual differences are observed in the datasets, there are diurnal variations with nighttime liquid water paths consistently higher than daytime values. The summer months of June, July, and August have the lowest liquid water paths and the highest cloud-base heights. Model outputs of cloud liquid water paths from the European Centre for Medium-Range Weather Forecasts (ECMWF) model and the Eta Model for 104 model output location time series (MOLTS) stations in the environs of the SGP central facility are compared to observations. The ECMWF and MOLTS median liquid water paths are greater than 3 times the observed values. The MOLTS data show lower liquid water paths in summer, which is consistent with observations, while the ECMWF data exhibit the opposite tendency. A parameterization of normalized cloud forcing that requires only cloud liquid water path and solar zenith angle is developed from the observations. The parameterization, which has a correlation coefficient of 0.81 with the observations, provides estimates of surface solar flux that are comparable to values obtained from explicit radiative transfer calculations based on plane-parallel theory. This parameterization is used to estimate the impact on the surface solar flux of differences in the liquid water paths between models and observations. Overall, there is a low bias of 50% in modeled normalized cloud forcing resulting from the excess liquid water paths in the two models. Splitting the liquid water path into two components, cloud thickness and liquid water content, shows that the higher liquid water paths in the model outputs are primarily a result of higher liquid water contents, although cloud thickness may a play a role, especially for the ECMWF model results.
Variations in the Teleconnection of ENSO and Summer Rainfall in Northern China: A Role of the Indian Summer Monsoon*
Authors: Feng Song , Hu Qi
Published: December 2007

Observational studies have created a dilemma on how El Niño–Southern Oscillation (ENSO) may have affected interannual variations of summer rainfall in northern China; some suggested a consistent effect while others showed a complete lack of effect. This dilemma is resolved in this study, which shows that ENSO has affected the summer rainfall in northern China and the effect has varied at multidecadal scales. The question of how the ENSO teleconnection with northern China rainfall variation was established is addressed, and an answer pointing to the Indian summer monsoon as a “facilitator” connecting ENSO and northern China rainfall variation is examined. The Indian monsoon circulation interacted with the regional circulations in northern China in some epochs and such interaction was interrupted in other epochs. When the interaction was active, the Indian monsoon variations originating from ENSO, during El Niño or La Niña, was extended to affect the rainfall variation in northern China, creating a teleconnection of ENSO with northern China rainfall. When the interaction weakened or was inactive, the ENSO effect languished. Additional analyses were done to address the related question of why the interactions have alternated. The alternation was suggested to result from variations of the large-scale circulation in the Eurasian continent. The circulation anomalies showed lowering (rising) 500-hPa geopotential height centered at Mongolia and western China in some epochs, enhancing cyclonic (anticyclonic) rotation in mid- and low-level winds and creating (disrupting) a moisture convoy from the Indian monsoon region to northern China and synergetic convergence/divergence anomalies in the monsoon region and in northern China. Results of this study contribute to the understanding of interannual and multidecadal variations of the summer rainfall in the semiarid region of northern China.
There's No Place Like Home
Authors: Sabia Joseph J.
Published: December 2007

Elderly housing surveys consistently report that older Americans prefer to remain living in their homes for as long as they are physically able. This study uses hazard models to estimate the effects of family composition changes, health conditions, housing characteristics, and local policies and amenities on aging-in-place decisions by older homeowners in the 1972-1992 Panel Study of Income Dynamics. The empirical results show that increases in property taxes and utility costs, changes in family composition, and diminished physical well-being are negatively associated with aging in place. Increased home equity, greater financial resources, and stronger ties to the community are positively associated with aging in place. Taken together, these findings suggest that policies designed to reduce the user costs of homeownership or to enhance the functionality of elderly homeowners may facilitate aging in place.
Cross-National Variations in the Correlation Between Frequency of Prayer and Health Among Older Europeans
Authors: Hank Karsten , Schaan Barbara
Published: December 2007

This research investigated the relationship between individuals' present frequency of prayer and various dimensions of older adults' physical and mental health in nine European countries. Using data from the 2004 Survey of Health, Ageing and Retirement in Europe, the authors estimated pooled and regional multivariate logistic regression models for four dependent variables: self-perceived general health, general physical health, functional limitations, and mental health. The results showed that the frequency of prayer in the population aged 50 years and older was negatively correlated with all four health outcomes in the analysis. Moreover, only minor cross-national variations were detected in the prayer-health nexus within continental Europe. Although the cross-sectional nature of the data prohibits any statements about causal relationships underlying the observed correlations, the evidence presented here suggests that religion should be considered a potentially relevant factor in future studies of older Europeans' health.
Value Solidity in Government and Business
Authors: van der Wal Zeger , Huberts Leo
Published: December 2007

This article reports on a survey study of 382 managers from a variety of public and private sector organizations, on the values that guide sectoral decision making. Just as some important classical differences emerge, a number of similarities between the public and private sector appear to result in a set of common core organizational values. Furthermore, the data support neither increasing adoption of business values in public sector organizations nor flirtation with public values by business sector managers. This contradicts expectations in the literature on new public management and corporate social responsibility, suggesting public—private value intermixing. Value solidity seems the dominant feature in both sectors. Additional analysis shows that “publicness,” the extent to which an organization belongs to the public or the private sector— rather than age, gender, years of service or a past in the other sector—strongly determines value preferences.
Effects of Aggression Replacement Training in Young Offender Institutions
Authors: Holmqvist Rolf , Hill Teci , Lang Annicka
Published: December 2007

This article reports a study where aggression replacement training (ART), combined with token economy, was compared with relationally oriented treatment at four residential treatment units in a nonrandomized design. In all, 57 adolescents in the ages between 16 and 19 participated. Outcome was measured as weighted indices of sentences and police suspicion reports. The results show no differences between the treatment models. In a separate analysis, the hypotheses were tested that those adolescents would relapse less frequently who admitted their crimes at intake or who could talk about guilt for their criminal acts. These hypotheses were refuted as main effects, but an interaction effect was found that suggests that adolescents with less consciousness of guilt got better results at the ART institutions. Case descriptions suggest that a more individualized approach to treatment, where ART is used for those adolescents who are motivated for it, would give better results.
Does the Transtheoretical Model (TTM) Explain Exercise Behavior in a Community-Based Sample of Older Women?
Authors: Findorff Mary J. , Hatch Stock Holly , Gross Cynthia R. , Wyman Jean F.
Published: December 2007

Objective: To determine whether patterns of exercise adoption by older women would conform to the Transtheoretical Model (TTM) of behavior change. Methods: Participants were randomized into an exercise group (walk 30 minutes per day, 5 days per week, plus balance exercises twice per week) or attention control (health education on topics other than exercise). The intervention was conducted over 28 weeks with 1-year follow-up. Results: Participants included 272 sedentary women aged 70 and above. Exercise adoption was higher in the intervention group (83% vs. 17% among controls). After 1 year, 60% of the intervention group was in action or maintenance, compared to 16% of the control group. Self-efficacy following the intervention predicted long-term exercise adherence. Discussion: Few studies have addressed longitudinal analysis of the TTM for exercise adoption. Most constructs from the TTM were useful in explaining exercise adoption in older sedentary women.
The Relationship Between Self-Efficacy and Cumulative Health Risk Associated With Health Behavior Patterns in Female Caregivers of Elderly Relatives With Alzheimer's Dementia
Authors: Rabinowitz Yaron G. , Mausbach Brent T. , Thompson Larry W. , Gallagher-Thompson Dolores
Published: December 2007

Objective: To promote caregiver well-being and to help caregivers persevere in their invaluable roles, personal resources that predict increased self-care and reduced health risk behaviors need to be identified. Method: This study examined relationships between self-efficacy beliefs in three distinct domains of caregiving and cumulative health risk associated with health behavior patterns. Results: Higher levels of self-efficacy for Obtaining Respite and self-efficacy for Controlling Upsetting Thoughts were found to be related to reduced health risk. Discussion: These findings suggest that caregivers who believe that they can remove themselves from the stresses of caregiving and who can manage the distorted cognitions often associated with caregiving may experience tangible benefits in health behaviors and, ultimately, improved physical health.
The Caregiver Stress Process and Health Outcomes
Authors: Son Juheui , Erno Amy , Shea Dennis G. , Femia Elia E. , Zarit Steven H. , Parris Stephens Mary Ann
Published: December 2007

Objective: The authors examine the impact of two caregiving stressors, care receivers' behavior problems (an objective stressor) and caregivers' feelings of overload (a subjective stressor), on three dimensions of caregiver health. Method: The participants were 234 primary caregivers of elderly relatives with dementia living in the community who completed a comprehensive interview about their current care situation, including stressors and health. Results: Higher levels of both objective and subjective stressors were associated with all three dimensions of caregiver health: poorer self-reported health, more negative health behaviors, and greater use of health care services. The association between objective stressors and health was mediated by caregivers' feelings of overload. Conclusions: These findings demonstrate caregivers' vulnerability to the effects of stressors across three dimensions of health and also underscore the importance of subjective appraisals of stress.
Western Worms! Explication of Aspects of Health Care Behavior Among Chamorro With HIV/AIDS
Authors: Kalwinsky Robert K.
Published: December 2007

By means of critical ethnography with a focus on historical dimensions, this article delineates the ways Chamorro with HIV/AIDS negotiate interaction with Western health staff. This effort targets a largely unstudied and disenfranchised population of a U.S. territory (Guam) through qualitative methods. Results indicate that (a) foundational historical patterns inform covert behaviors, that is, the longstanding colonization of Chamorro culture has implications for communication, and (b) the residual influence of the investigation of lytico-bodig affects conceptualization and discussion of disease. At the same time, historically grounded forms such as the use of healers offer clients culturally sanctioned means of resistance to hegemonic medical structures. Findings have implications for nursing practice in the clinical setting.
Psychosocial Mediators of a Walking Intervention Among African American Women
Authors: Dunn Mary Z.
Published: December 2007

Many Americans are sedentary and would reduce their disease risk if they increased their levels of physical activity to 30 minutes of moderate activity most days of the week. This descriptive exploratory study addresses how to maximize adherence to a physical activity prescription. A sample of 14 older African American women enrolled in a walking intervention study participated in three focus-group discussions of barriers to and facilitators of walking. Focus groups were audiotaped, transcribed, and examined by three nurse researchers using analytic induction, content analysis, and grounded theory techniques. Women who participated in the focus-group discussions identified lack of family support, perceived or real family obligations, personal health status, and neighborhood safety as factors influencing adherence to physical activity. A necessary component of successful walking maintenance was the confidence and support of the woman's family. The most compelling reason for continued walking in this group was to help others.
Health Disparities and Health-Seeking Behavior Among Latino Men
Authors: MacNaughton Neil S.
Published: December 2007

Many studies examining Latino health-seeking behavior have focused on comparing Latinos with other ethnic groups, primarily with Whites and African Americans. However, without the benefit of intragroup or intracultural comparisons, such studies fail to identify the subtle variation in health-seeking strategies and the range of needs within the Latino ethnic group, and thus are compromised in their capacity to guide and improve practice and policy. This article reviews the literature regarding health-seeking behavior and Latino men. Important factors identified include gender, occupation, and responsiveness of the health care system along with characteristics of the individual.
Muslim Women's Experiences With Health Care Providers in a Rural Area of the United States
Authors: Simpson Jennifer L. , Carter Kimberly
Published: December 2007

This study used phenomenology to explore the experience of Muslim women through descriptions of their encounters with health care providers in a rural area. Participants (N = 7 ) were eligible for inclusion if the foreign-born woman had lived in the area for at least 2 years, had interaction with a health care provider within the last 6 months, and was able to articulate her experience either in English or through a interpreter. Data were recorded, transcribed, coded, and analyzed for the emergence of reoccurring themes, employing decision trails. Constant comparative analysis was used to promote the integrity of the data. Three themes were identified: (1) perceived power of the provider, (2) religiously defined gender relations, and (3) being a stranger in the U.S. healthcare system. Education of the Muslim patient and the provider is needed to increase health care satisfaction and use by rural Muslim women.
Career Construction and Subjective Well-Being
Authors: Hartung Paul J. , Taber Brian J.
Published: December 2007

Experienced happiness and reported life contentment represent cardinal elements of subjective well-being (SWB). Achieving happiness and contentment with work and other domains, such as love, play, and community, constitute fundamental life goals. Career construction offers a developmental theory of vocational behavior and a career assessment and counseling model counselors can use to promote client SWB. As an intervention model, career construction assists individuals with using work to foster self-completion and derive meaning, satisfaction, and happiness as they design their lives. Career construction counseling promotes SWB because its aims are consistent with increasing both immediate life satisfaction and overall life contentment. The present analysis describes the basic principles and practice of career construction and explains the career style interview as an assessment and counseling method useful for assisting individuals to identify and pursue self-selected goals and projects, endeavors that contribute to SWB.
Following Passionate Interests to Well-Being
Authors: Dik Bryan J. , Hansen Jo-Ida C.
Published: December 2007

This article describes the relationship between interests and well-being by conceptualizing interest as both an emotional state and a stable disposition. First, interest is explored as a distinct emotion or affective state, itself a form of well-being that also leads to other forms of well-being by facilitating the development of diverse life experiences and competencies. Next, the theoretical linkage between affective interest and stable, enduring interests (or what interest inventories measure) is summarized. Finally, evidence suggesting that interests predict well-being in the domains of work and leisure is reviewed. Part of living the good life, the authors conclude, means living the interested life.
Does Happiness Promote Career Success?
Authors: Boehm Julia K. , Lyubomirsky Sonja
Published: December 2007

Past research has demonstrated a relationship between happiness and workplace success. For example, compared with their less happy peers, happy people earn more money, display superior performance, and perform more helpful acts. Researchers have often assumed that an employee is happy and satisfied because he or she is successful. In this article, the authors review evidence in support of an alternative hypothesis—namely, that happiness is a source of why particular employees are more successful than others. To this end, the authors consider evidence from three types of studies—cross-sectional, longitudinal, and experimental—that relate happiness to various work outcomes. Taken together, the evidence suggests that happiness is not only correlated with workplace success but that happiness often precedes measures of success and that induction of positive affect leads to improved workplace outcomes.
Promoting Subjective Well-Being at Work
Authors: Russell Joyce E. A.
Published: December 2007

Research has clearly shown the relationship between subjective well-being and work performance, even though there is debate over the causality of that relationship (i.e., does subjective well-being cause higher work performance or does greater work performance lead to subjective well-being?). Regardless, researchers and practitioners would agree that having employees who are productive and have high subjective well-being is valuable. The purpose of this article is to review research in this area and to discuss strategies for promoting well-being at the workplace.
Using a Theory of Vocational Personalities and Work Environments to Explore Subjective Well-Being
Authors: Don Gottfredson Gary , Duffy Ryan D.
Published: December 2007

Most people have positive views of their general happiness or subjective well-being (SWB). Furthermore, SWB tends to be stable and rebound to prior levels following events or circumstances that might be expected to change its level. The authors speculate about ways a theory of person–environment transactions—Holland's theory of vocational personalities and work environments—may help individuals understand some of the observed features of SWB. Testable hypotheses are offered as suggestions for advancing research on both the theory and SWB.
Indexes of Validity and Reliability for Cross-Societal Measures
Authors: Denton Trevor
Published: December 2007

Extracting measures from classical ethnographies has always necessitated proxy indicators in cross-societal research. Methods are given for calculating indexes of validity and reliability for both a low inference measure x and high inference proxy measure y of the same conceptual variable Z. Where two different ethnographic descriptions A and B exist for each society in a sample, low inference measures x A and x B are used to assess validity and reliability from the classical “true score” measurement model x = τ + ε X, τ is the true score, ε X is error, ξ[E X] = 0. Tests establish whether the model fits data. Reliability is defined to be (1 — Var[E X]/Var[X]). Validity is Var[T]/Var[X]. The validity and reliability of high inference measure y are increased by fitting a curve x = f(y) + ε f(y), ξ[E f(y)] = 0, to data. Standard cross-cultural sample examples are given. Solutions for cross-societal research may be considered for cross-cultural research.
Diverse roles of actin in C. elegansearly embryogenesis
Authors: Velarde Nathalie , Gunsalus Kristin C , Piano Fabio
Published: December 2007

Background

The actin cytoskeleton plays critical roles in early development in Caenorhabditis elegans. To further understand the complex roles of actin in early embryogenesis we use RNAi and in vivo imaging of filamentous actin (F-actin) dynamics.

Results

Using RNAi, we found processes that are differentially sensitive to levels of actin during early embryogenesis. Mild actin depletion shows defects in cortical ruffling, pseudocleavage, and establishment of polarity, while more severe depletion shows defects in polar body extrusion, cytokinesis, chromosome segregation, and eventually, egg production. These defects indicate that actin is required for proper oocyte development, fertilization, and a wide range of important events during early embryogenesis, including proper chromosome segregation. In vivo visualization of the cortical actin cytoskeleton shows dynamics that parallel but are distinct from the previously described myosin dynamics. Two distinct types of actin organization are observed at the cortex. During asymmetric polarization to the anterior, or the establishment phase (Phase I), actin forms a meshwork of microfilaments and focal accumulations throughout the cortex, while during the anterior maintenance phase (Phase II) it undergoes a morphological transition to asymmetrically localized puncta. The proper asymmetric redistribution is dependent on the PAR proteins, while both asymmetric redistribution and morphological transitions are dependent upon PFN-1 and NMY-2. Just before cytokinesis, actin disappears from most of the cortex and is only found around the presumptive cytokinetic furrow. Finally, we describe dynamic actin-enriched comets in the early embryo.

Conclusion

During early C. elegans embryogenesis actin plays more roles and its organization is more dynamic than previously described. Morphological transitions of F-actin, from meshwork to puncta, as well as asymmetric redistribution, are regulated by the PAR proteins. Results from this study indicate new insights into the cellular and developmental roles of the actin cytoskeleton.
Morbidity at elementary school entry differs by sex and level of residence urbanization: a comparative cross-sectional study
Authors: Yang Rea-Jeng , Sheu Jiunn-Jye , Chen Huey-Shys , Lin Kuan-Chia , Huang Hsiu-Li
Published: December 2007

Background

Health is vital to a child's learning in school and success in life. Therefore, early physical examination, and follow-up if necessary, would bring parents' attention to their child's health and would likely improve outcomes. The purposes of this study are twofold: to assess the health status of first-graders and to examine the health status differences between sexes, levels of residence urbanization, and quantity of available medical resources.

Methods

This is a comparative descriptive study. Data from the 2002 Student Entry Physical Examination (SEPE) and Student Medical History Inventory (SMHI) were obtained from 203 public and private elementary schools in northern Taiwan where a population of 53,053 students was included. Frequencies, independent sample t test, one-way ANOVA along with Scheff's post hoc test, and Pearson's correlation were conducted using SPSS.

Results

This study showed that 13.7% of students had at least one diagnosed disease from the SMHI reported by parents. Moreover, the SEPE indicated that 79.5% students had at least one health concern. Dental caries, myopia, and obesity were the most prevalent health problems among the first-graders (69.6%, 27.1%, and 9.5%, respectively). Research results show that there were significant differences in the prevalence of dental caries, myopia, and obesity between different sexes and among levels of urbanization. However, the quantity of available medical resources made no significant difference.

Conclusion

Elementary school entry physical examination is an important way to detect students' health problems. It is suggested that school health interventions consider students' health profiles along with their sex and level of urbanization in planning. More research is needed to find the risk factors of the health problems. Additionally, the creation of a school health committee is suggested to implement and evaluate the entry health examination program.