bluuebunny/crossref_metadata_2025 huggingface dataset:
Data Quality Assessment and the Long-Term Trend of Ground Solar Radiation in China
Authors: Shi Guang-Yu , Hayasaka Tadahiro , Ohmura Atsumu , Chen Zhi-Hua , Wang Biao , Zhao Jian-Qi , Che Hui-Zheng , Xu Li
Published: May 2008

Solar radiation is one of the most important factors affecting climate and the environment. Routine measurements of irradiance are valuable for climate change research because of long time series and areal coverage. In this study, a set of quality assessment (QA) algorithms is used to test the quality of daily solar global, direct, and diffuse radiation measurements taken at 122 observatories in China during 1957–2000. The QA algorithms include a physical threshold test (QA1), a global radiation sunshine duration test (QA2), and a standard deviation test applied to time series of annually averaged solar global radiation (QA3). The results show that the percentages of global, direct, and diffuse solar radiation data that fail to pass QA1 are 3.07%, 0.01%, and 2.52%, respectively; the percentages of global solar radiation data that fail to pass the QA2 and QA3 are 0.77% and 0.49%, respectively. The method implemented by the Global Energy Balance Archive is also applied to check the data quality of solar radiation in China. Of the 84 stations with a time series longer that 20 yr, suspect data at 35 of the sites were found. Based on data that passed the QA tests, trends in ground solar radiation and the effect of the data quality assessment on the trends are analyzed. There is a decrease in ground solar global and direct radiation in China over the years under study. Although the quality assessment process has significant effects on the data from individual stations and/or time periods, it does not affect the long-term trends in the data.
An Urban Parameterization for a Global Climate Model. Part I: Formulation and Evaluation for Two Cities
Authors: Oleson K. W. , Bonan G. B. , Feddema J. , Vertenstein M. , Grimmond C. S. B.
Published: May 2008

Urbanization, the expansion of built-up areas, is an important yet less-studied aspect of land use/land cover change in climate science. To date, most global climate models used to evaluate effects of land use/land cover change on climate do not include an urban parameterization. Here, the authors describe the formulation and evaluation of a parameterization of urban areas that is incorporated into the Community Land Model, the land surface component of the Community Climate System Model. The model is designed to be simple enough to be compatible with structural and computational constraints of a land surface model coupled to a global climate model yet complex enough to explore physically based processes known to be important in determining urban climatology. The city representation is based upon the “urban canyon” concept, which consists of roofs, sunlit and shaded walls, and canyon floor. The canyon floor is divided into pervious (e.g., residential lawns, parks) and impervious (e.g., roads, parking lots, sidewalks) fractions. Trapping of longwave radiation by canyon surfaces and solar radiation absorption and reflection is determined by accounting for multiple reflections. Separate energy balances and surface temperatures are determined for each canyon facet. A one-dimensional heat conduction equation is solved numerically for a 10-layer column to determine conduction fluxes into and out of canyon surfaces. Model performance is evaluated against measured fluxes and temperatures from two urban sites. Results indicate the model does a reasonable job of simulating the energy balance of cities.
Inverse Parameter Estimation of the Turbulent Surface Layer from Single-Level Data and Surface Temperature
Authors: Martano P.
Published: May 2008

A simple inverse parameter estimation method is used in a practical diagnostic approach to obtain the surface roughness lengths and surface resistance parameters from a chi-square cost function containing measurements of wind speed and air surface temperature differences in the atmospheric surface layer. The estimated parameters allow the calculation of the turbulent fluxes of momentum and heat and the surface-layer profiles of wind speed temperature and humidity from single-level data of wind speed and variance, air temperature and humidity, surface temperature, and total heat flux (sum of sensible and latent fluxes, estimated as net radiation minus soil heat flux). The procedure, which is potentially applicable when fast response data are not available without the necessity of external parameters (with the exception of the displacement height), is tested over a field dataset in southern Italy.
Observational and Numerical Evidence of Depressed Convective Boundary Layer Heights near a Mountain Base
Authors: De Wekker Stephan F. J.
Published: May 2008

Recent field and numerical studies show evidence of the existence of a convective boundary layer height depression near a mountain base. This depression can have implications for air pollutant transport and concentrations in complex terrain. To investigate the mechanisms underlying this phenomenon, idealized simulations with a mesoscale numerical model are performed and combined with available observations. The idealized simulations with a single mountain ridge of various dimensions suggest that the depression evolves in time, is most pronounced in the late afternoon, and becomes larger as slope steepness increases. Observations and modeling results show that the atmosphere is heated more intensely near the mountain base than far away from the mountain base, not only inside the boundary layer but also above. The enhanced heating aloft affects boundary layer growth near the mountain base and is associated with the boundary layer height depression. An analysis of the different terms in the temperature tendency equation indicates that vertical and horizontal advection of warm air, associated with the thermally driven circulation along the mountain slope, play a role in this enhanced heating aloft.
The Operational Mesogamma-Scale Analysis and Forecast System of the U.S. Army Test and Evaluation Command. Part II: Interrange Comparison of the Accuracy of Model Analyses and Forecasts
Authors: Liu Yubao , Warner Thomas T. , Astling Elford G. , Bowers James F. , Davis Christopher A. , Halvorson Scott F. , Rife Daran L. , Sheu Rong-Shyang , Swerdlin Scott P. , Xu Mei
Published: May 2008

This study builds upon previous efforts to document the performance of the U.S. Army Test and Evaluation Command’s Four-Dimensional Weather Modeling System using conventional metrics. Winds, temperature, and specific humidity were verified for almost 15 000 forecasts at five U.S. Army test ranges using near-surface mesonet data. The primary objective was to use conventional metrics to characterize the degree to which forecast accuracy varies from range to range, within the diurnal cycle, with elapsed forecast time, and among the seasons. It was found that there are large interrange differences in forecast error, with larger errors typically associated with the ranges located near complex orography. Similarly, significant variations in accuracy were noted for different times in the diurnal cycle, but the diurnal dependency varied greatly among the ranges. Factor of 2 differences in accuracy were also found across the seasons.
The Operational Mesogamma-Scale Analysis and Forecast System of the U.S. Army Test and Evaluation Command. Part III: Forecasting with Secondary-Applications Models
Authors: Sharman Robert D. , Liu Yubao , Sheu Rong-Shyang , Warner Thomas T. , Rife Daran L. , Bowers James F. , Clough Charles A. , Ellison Edward E.
Published: May 2008

Output from the Army Test and Evaluation Command’s Four-Dimensional Weather System’s mesoscale model is used to drive secondary-applications models to produce forecasts of quantities of importance for daily decision making at U.S. Army test ranges. Examples of three specific applications—a sound propagation model, a missile trajectory model, and a transport and diffusion model—are given, along with accuracy assessments using cases in which observational data are available for verification. Ensembles of application model forecasts are used to derive probabilities of exceedance of quantities that can be used to help range test directors to make test go–no-go decisions. The ensembles can be based on multiple meteorological forecast runs or on spatial ensembles derived from different soundings extracted from a single meteorological forecast. In most cases, the accuracies of the secondary-application forecasts are sufficient to meet operational needs at the test ranges.
Dynamic LES Modeling of a Diurnal Cycle
Authors: Basu Sukanta , Vinuesa Jean-François , Swift Andrew
Published: May 2008

The diurnally varying atmospheric boundary layer observed during the Wangara (Australia) case study is simulated using the recently proposed locally averaged scale-dependent dynamic subgrid-scale (SGS) model. This tuning-free SGS model enables one to dynamically compute the Smagorinsky coefficient and the subgrid-scale Prandtl number based on the local dynamics of the resolved velocity and temperature fields. It is shown that this SGS-model-based large-eddy simulation (LES) has the ability to faithfully reproduce the characteristics of observed atmospheric boundary layers even with relatively coarse resolutions. In particular, the development, magnitude, and location of an observed nocturnal low-level jet are depicted quite well. Some well-established empirical formulations (e.g., mixed layer scaling, spectral scaling) are recovered with good accuracy by this SGS parameterization. The application of this new-generation dynamic SGS modeling approach is also briefly delineated to address several practical wind-energy-related issues.
Polarimetric Radar Observations at Low Levels during Tornado Life Cycles in a Small Sample of Classic Southern Plains Supercells*
Authors: Van Den Broeke Matthew S. , Straka Jerry M. , Rasmussen Erik N.
Published: May 2008

Preliminary schematics of polarimetric signatures at low levels in southern plains classic supercells are developed for pretornado, tornado, and tornado demise times from a small collection of cases, most of which are cyclic tornado producers. Characteristic signatures and patterns are identified for the reflectivity factor (ZHH), the differential reflectivity (ZDR), the correlation coefficient (ρhv), and the specific differential phase (KDP). Signatures likely related to an ongoing tornado are also discussed. Major findings in ZHH at tornado times include “wings” of higher values often extending away from the updraft region, a stronger gradient on the west side of the echo appendage, and a local maximum at the storm location favorable for tornadogenesis. Increasing cyclonic curvature of the hook-echo region was noted through the tornado life cycle. The ZDR tended to indicate hail shafts most commonly at tornado times, with the highest storm values typically located along the storm’s forward flank throughout the tornado life cycle. A ZDR minimum often occurred at the tornado-favorable location, while low ZDR occasionally trailed the tornado region. Storm-minimum ρhv typically occurred at the tornado-favorable location at tornado times and in hail shafts or heavy rain areas at other times. Another region of low correlation was the storm updraft, while the highest storm correlation was typically found in the downwind light-precipitation shield. The KDP typically exhibited a storm-core temporal maximum at tornado times, with the highest storm values in regions of hail and heavy rain and the lowest values in the downwind light-precipitation region. Values in the tornado-favorable region were typically near zero and sometimes strongly negative.
Frequency of Symptomatic Relapses of Group A β-Hemolytic Streptococcal Tonsillopharyngitis in Children From 4 Pediatric Practices Following Penicillin, Amoxicillin, and Cephalosporin Antibiotic Treatment
Authors: Casey Janet R. , Kahn Raymond , Gmoser Dean , Atlas Elissa , Urbani Karen , Luber Stephen , Pellman Harry , Pichichero Michael E.
Published: May 2008

The objective was to determine the frequency of early symptomatic relapses following antibiotic treatment for group A β-hemolytic streptococcal (GABHS) tonsillopharyngitis in children from Rochester, New York; Houston, Texas; Spokane, Washington; and Los Angeles, California (2004-2006). The study included 4278 patients. The proportion with a bacteriologic relapse of GABHS tonsillopharyngitis within 1 to 5 days of completing a 10-day treatment course was 8% (penicillin and bicillin), 6% (amoxicillin), 2% (first-generation cephalosporin), and 1% (second-generation and third-generation cephalosporin; P = .0001); symptomatic relapses occurred within 6 to 20 days after completion of therapy in 16%, 14%, 9%, and 7% of cases ( P = .0001). Cases from New York and Washington had higher penicillin or amoxicillin failure rates than cases from Texas and California. The frequency of symptomatic relapses of GABHS tonsillopharyngitis, therefore, differs according to the antibiotic treatment selected; the trend for such relapses being penicillin or amoxicillin > cephalosporins although geographic differences may occur.
Analgesia and Sedation Practices for Incarcerated Inguinal Hernias in Children
Authors: Al-Ansari Khalid , Sulowski Christopher , Ratnapalan Savithiri
Published: May 2008

In this study, the use of medications for analgesia and/or sedation for incarcerated inguinal hernia reductions in the emergency department was analyzed. A retrospective chart review was conducted for all patients presenting to a pediatric emergency department with incarcerated inguinal hernia from 2002 to 2005. A total of 99 children presented with incarcerated hernias during the study period. The median age was 11 months. Forty-four percent of children received medication for the procedure, of them 75% received parenteral and 25% oral or intranasal medications. Forty-five percent of children who received medication went through at least 1 hernia reduction attempt initially without medications. More than half the children with incarcerated inguinal hernias did not receive any medication for pain and/or sedation prior to hernia reduction. Guidelines for medication use for children with incarcerated inguinal hernias need to be developed.
Methodological Considerations for Micro Studies of UNIA Divisions
Authors: Stephens Ronald J.
Published: May 2008

This article explores various analytical and interpretive tools and historical methods and techniques of historical research and writing for conducting research on local Garveyism and the Universal Negro Improvement Association and African Communities League (UNIA-ACL). The article suggests a new framework that could be used to ably describe, interpret, and evaluate a micro-level analysis of UNIA-ACL divisions of the 1920s and 30s. In an effort to increase knowledge about the role and impact of the Garvey Movement in the United States, the article suggests some methodological considerations.
Insisting on Digital Equity
Authors: Gorski Paul C.
Published: May 2008

In the United States, where technological progress is portrayed as humanistic progress, computer technologies often are hailed as the great equalizers. Even within progressive education movements, such as multicultural education, the conversation about instructional technology tends to center more on this or that wonderful Web site or piece of software than on equitable access to these technologies. In this article, the author challenges people working at the intersections of multicultural and instructional technology, insisting that our first concern must be the elimination of digital inequities. It is only when we reframe the dominant discourse in this way that we practice authentic multicultural education.
Evaluation of Population Pharmacokinetics and Exposure‐Response Relationship With Coadministration of Amlodipine Besylate and Olmesartan Medoxomil
Authors: Rohatagi Shashank , Carrothers Timothy J. , Kshirsagar Smita , Khariton Tatiana , Lee James , Salazar Daniel
Published: May 2008

Population pharmacokinetic models for amlodipine and olmesartan were developed using data collected from 4 phase I studies in healthy volunteers and 1 phase III study in subjects with mild to severe hypertension. A 2‐compartment and a 1‐compartment model best described the pharmacokinetics of olmesartan and amlodipine, respectively; both agents were characterized by first‐order elimination/absorption and an absorption time lag. The analysis shows that neither agent had a clinically significant impact on the clearance of the other. The impact of covariates on the clearance of olmesartan and amlodipine was similar after coadministration of amlodipine besylate and olmesartan medoxomil as separate entities or as a fixed‐dose combination compared with monotherapy. The effect of exposure to amlodipine and olmesartan on the change in trough seated diastolic blood pressure was best described by linear and maximum effect (Emax) models, respectively. Black race was the most important covariate in the exposure‐response model, decreasing the maximal possible effect of olmesartan on blood pressure while increasing the effect of amlodipine, without influencing pharmacokinetic parameters. The drug effect of combination therapy was defined on the basis of exposure to both compounds and was greater than the effect of monotherapy with either agent.
Population Pharmacokinetic Modeling of Epoetin Delta in Pediatric Patients With Chronic Kidney Disease
Authors: Knebel William , Palmen Mary , Dowell James A. , Gastonguay Marc
Published: May 2008

This analysis quantifies the population pharmacokinetics of subcutaneous and intravenous epoetin delta, an epoetin produced in a human cell line, in pediatric patients with chronic kidney disease and estimates the effects of covariate factors on epoetin delta and epoetin alfa pharmacokinetic parameters. Erythropoietin serum concentration data, taken from a phase III study conducted in 60 patients aged 1 to 17 years, were best described by a 1‐compartment model with first‐order absorption and elimination. The typical point estimates were clearance (0.268 L/h), central volume of distribution (1.03 L), absorption rate constant (0.0554 h−1), and bioavailability (0.708) for a 35‐kg male ≤10 years who was predialysis and on subcutaneous epoetin delta treatment. Erythropoietin pharmacokinetic parameters were similar in pediatric patients as compared with adults when scaled by weight. The subcutaneous administration of epoetin alfa exhibited lower systemic bioavailability than subcutaneous administration of epoetin delta.
An Improved Approach for Confirmatory Phase III Population Pharmacokinetic Analysis
Authors: Hu Chuanpu , Zhou Ghui
Published: May 2008

In contrast to the traditional extensive exploratory approach, the authors propose a confirmatory approach to phase III population pharmacokinetics for regulatory submissions. In their approach, they recommend a prespecified primary analysis based on phase I/II data and phase III study design. Their approach also incorporates several specific sensitivity analyses to evaluate the robustness of the conclusions. According to statistical rationale, this approach eliminates certain biases that may occur in the estimated covariate effects, thereby precluding potentially unnecessary dosing adjustments and allowing for more accurate assessments of ambiguity in the results. Because exploration is vastly reduced, the analysis time is also substantially shortened. The proposed analyses are relatively easy to implement, although careful and prospective planning is required. Applications of the approach are provided, including 2 phase III analyses for regulatory submissions. Differences between the proposed approach and the commonly used extensive exploratory analyses submitted to regulatory agencies were small and consistent with practical expectations.
Agenda Setting in Civic Development
Authors: Kiousis Spiro , McDevitt Michael
Published: May 2008

This study examines the role of agenda setting in affecting voter turnout using panel data of adolescents in Arizona, Florida, and Colorado from 2002 and 2004. Specifically, a model is developed probing the multiple influences of interactive civic instruction, media attention, and discussion on the following sequence of outcomes: perceived issue importance, opinion strength, political ideology, and finally voter turnout. The results suggest that agenda setting serves as a critical intrinsic process in political socialization contributing to the crystallization of political predispositions, which lead to electoral participation. The implications of the findings are discussed.
Psychopathy, Intelligence, and Recidivism in Child Molesters
Authors: Beggs Sarah M. , Grace Randolph C.
Published: May 2008

The authors studied the relationships between psychopathy, intelligence, and offending in a sample of treated child molesters ( N = 216). Regression analyses showed that psychopathy (as measured by the Psychopathy Checklist—Revised) was strongly related to both offense history and recidivism during follow-up. Intelligence (assessed using four-subtest short forms of the Wechsler Adult Intelligence Scale—Revised and Third Versions) was not related to offending. However, there was a significant interaction between intelligence and psychopathy on recidivism: Offenders with relatively low intelligence and high psychopathy scores were more than 4 times as likely to have received a sexual reconviction as other offenders. Results are discussed in terms of implications for risk assessment.
Savry Risk Assessment in Violent Dutch Adolescents
Authors: Lodewijks Henny P.B. , Doreleijers Theo A.H. , De Ruiter Corine
Published: May 2008

This study examines the predictive validity of the Structured Assessment of Violence Risk in Youth (SAVRY) by examining relationships between SAVRY scores and violent reoffending during a 3-year period after sentencing. Two types of sentences were studied: a mandatory treatment order ( N = 77) and a juvenile prison sentence ( N = 40). The predictive validity of the SAVRY was significant for the two types of sentences. The predictive validity of the unstructured clinical judgment proved to be not significant. Support was found for the hypothesis that the juvenile court's sentence (treatment versus detention) might have been influenced by the unstructured clinical risk assessment of the mental health experts, even though this assessment is a poor predictor of violent reoffending.
Do Batterer Subtypes Actually Matter? Treatment Completion, Treatment Response, and Recidivism Across a Batterer Typology
Authors: Huss Matthew T. , Ralston Anthony
Published: May 2008

It has been proposed that domestic violence offenders can be classified into distinct subgroups based on psychopathology and generality and severity of violence. This study examined a clinical sample of batterers to identify whether there were differences across batterer subtypes in regard to treatment completion, immediate treatment response, and recidivism. Indices of pathology, partner violence, and generalized violence were used to cluster analyze a sample of 175 batterers. The resulting three-cluster solution produced three different groups of batterers identified as generally violent/antisocial, borderline/ dysphoric, and family-only batterers. Results suggest that there are differences in treatment-related variables across batterer subtypes but that these differences also depend on the specific outcome variables and are not always consistent.
The Effects of Media Violence Exposure On Criminal Aggression
Authors: Savage Joanne , Yancey Christina
Published: May 2008

The article presents a meta-analysis of studies—yielding 26 independent samples of subjects—on the relationship between exposure to media violence and violent aggression. Mean effect sizes from aggregate and experimental studies do not suggest that media violence and criminal aggression are positively associated, but findings from prospective longitudinal studies are more ambiguous. Summary statistics based on models strictly conforming to each study's original design were compared to post hoc models (in which measures or model specification were not consistent with the original description). Overall, “original” models, controlling for “trait,” did not suggest that exposure to media violence is associated with criminal aggression. The summary statistic for boys reached statistical significance, but the effect size was small, and conclusions based on this finding are attenuated because of known biases in the coefficients estimated.
Introduction to the Symposium on The Foundations of Organizing: The Contribution from Garfinkel, Goffman and Sacks
Authors: Samra-Fredericks Dalvir , Bargiela-Chiappini Francesca
Published: May 2008

This paper outlines a case for bringing the work of three scholars — Garfinkel (ethnomethodology), Goffman (interaction order/dramaturgy), Sacks (conversation analysis) — into the management and/or organization studies field. It specifically attends to the ways their work adds to understandings of the foundations of organizing. Further, we argue for studies of naturally occurring interaction in ways forged by these scholars and substantiate this move through touching on a number of domains of study where a contribution would be forthcoming, indicated here through the conceptual terrain of practice, identity, power and process theorizing. It is an endeavour which also problematizes the interview `method'. Crucially too, as part of this discussion, we not only summarize elements from these three scholars' legacies for our field, but also introduce the four papers selected for this Symposium Issue. We highlight the ways they take up particular threads and offer empirical illustrations of fine-grained studies of the foundations of organizing.
Organization in Actual Episodes of Work: Harvey Sacks and Organization Studies
Authors: Llewellyn Nick
Published: May 2008

This paper explores the relevance of Harvey Sacks' work for contemporary organization studies. Sacks encourages analysts to tether their studies to real-time workplace activities; ordinary scenes of work are recorded, slowed down and made the central object of study. Something of Sacks' analytic mentality and style are illustrated through the analysis of two data extracts: an emergency 999 call and a face-to-face sales encounter. A distinctive way of doing organizational analysis is discussed that foregrounds knowledgeability and agency via the examination of sequence and method. Sacks raises the possibility that organization might be recoverable from the fine-grained detail of actual episodes. The idea that order, intelligibility and the constitution of social scenes might have a basis aside from the more general notion of discourse is discussed.
Creating an Interactive and Responsive Teaching Environment to Inspire Learning
Authors: Paladino Angela
Published: May 2008

Teaching students to understand, disable, and solve problems is one of the largest challenges educators face in undergraduate marketing education. My teaching philosophy is centered on the creation of an interactive learning environment. This encompasses problem-based teaching and collaborative learning to foster discussions between students and between faculty members and students. This setting is largely supported by the creation of technological resources and the design of feedback systems. Feedback provides students with the opportunity to gauge their understanding of the course and to improve. The technological resources assist students to learn at their own pace. Consisting of digital lecture recordings, an on-line tutor, and a “bank” of lecture slides and assessment materials, these online resources serve to provide students with feedback and 24-hr support to assist with their learning. Variety in teaching tools, the creation of an interactive and supportive environment, and the implementation of high standards have motivated my students to attend class and excel in their performance. It has also improved their transferable skill development and their value to employers for years to come.
Section Modulus is the Optimum Geometric Predictor for Stress Fractures and Medial Tibial Stress Syndrome in both Male and Female Athletes
Authors: Franklyn Melanie , Oakes Barry , Field Bruce , Wells Peter , Morgan David
Published: May 2008

Background

Various tibial dimensions and geometric parameters have been linked to stress fractures in athletes and military recruits, but many mechanical parameters have still not been investigated.

Hypotheses

Sedentary people, athletes with medial tibial stress syndrome, and athletes with stress fractures have smaller tibial geometric dimensions and parameters than do uninjured athletes.

Study Design

Cohort study; Level of evidence, 3.

Methods

Using a total of 88 subjects, male and female patients with either a tibial stress fracture or medial tibial stress syndrome were compared with both uninjured aerobically active controls and uninjured sedentary controls. Tibial scout radiographs and cross-sectional computed tomography images of all subjects were scanned at the junction of the midthird and distal third of the tibia. Tibial dimensions were measured directly from the films; other parameters were calculated numerically.

Results

Uninjured exercising men have a greater tibial cortical cross-sectional area than do their sedentary and injured counterparts, resulting in a greater value of some other cross-sectional geometric parameters, particularly the section modulus. However, for women, the cross-sectional areas are either not different or only marginally different, and there are few tibial dimensions or geometric parameters that distinguish the uninjured exercisers from the sedentary and injured subjects. In women, the main difference between the groups was the distribution of cortical bone about the centroid as a result of the different values of section modulus. Last, medial tibial stress syndrome subjects had smaller tibial cross-sectional dimensions than did their uninjured exercising counterparts, suggesting that medial tibial stress syndrome is not just a soft-tissue injury but also a bony injury.

Conclusion

The results show that in men, the cross-sectional area and the section modulus are the key parameters in the tibia to distinguish exercise and injury status, whereas for women, it is the section modulus only.
Effect of Osteochondral Graft Insertion Forces on Chondrocyte Viability
Authors: Patil Shantanu , Butcher William , D'Lima Darryl D. , Steklov Nikolai , Bugbee William D. , Hoenecke Heinz R.
Published: May 2008

Background

Because chondrocytes are responsible for articular cartilage matrix synthesis and maintenance, reduced chondrocyte viability could compromise graft survival, healing, and clinical outcome.

Hypothesis

Typical forces used in osteochondral grafting reduce the viability of the chondrocytes in the graft. Study Design: Controlled laboratory study.

Methods

Osteochondral grafting was performed in 4 fresh-frozen cadaver knees (n = 16 per knee). Impact force was measured during extrusion of the donor graft from the harvester into the recipient site, seating the graft flush with the articular surface of the surrounding cartilage using a tamp, and recessing the graft surface below the recipient articular surface. The magnitudes of forces measured during cadaver surgery (200,400, and 800 N) were reproduced using a drop-tower apparatus on 80 fresh osteochondral grafts harvested from knee blocks provided by tissue banks. Cell viability and glycosaminoglycan release in media were measured at 48 hours after injury.

Results

Forces were relatively low (range, 124-356 N) during graft extrusion from the harvester into the recipient defect or during flush seating (range, 191-418 N) of the graft. Attempts to recess the graft generated significantly greater force (range, 147-685- P < .01). When the donor graft length was 2 mm longer than the depth of the recipient hole, the mean impact force generated was even higher (range, 240-1114 N) than the force seen in a donor graft of equal length. No reduction in viability was seen at 200-N and 400-N impacts. However, a significant decrease in chondrocyte viability was seen in the group impacted with 800 N (only 50% of cells were viable, compared with 91 % in the sham group; P < .01). Glycosaminoglycan levels in culture media did not correlate significantly with insertion force.

Conclusion

Typical graft insertion forces did not significantly reduce chondrocyte viability. However, increased graft length relative to the depth of the recipient hole and attempts to recess the graft generated higher forces, which reduced chondrocyte viability.

Clinical Relevance

Any theoretical benefits of cancellous bone compaction that may occur in grafts that are recessed or are longer than the recipient holes must be balanced against the potential reduction in chondrocyte viability.
Prospective Clinical Comparisons of Anatomic Double-Bundle versus Single-Bundle Anterior Cruciate Ligament Reconstruction Procedures in 328 Consecutive Patients
Authors: Kondo Eiji , Yasuda Kazunori , Azuma Hirotaka , Tanabe Yoshie , Yagi Tomonori
Published: May 2008

Background

Several trials have been conducted to compare the clinical results between anatomic double-bundle and single-bundle anterior cruciate ligament (ACL) reconstruction procedures. In these studies, however, the number of patients was insufficient to compare the clinical results of the 2 procedures.

Hypothesis

The anatomic double-bundle procedure may be significantly better concerning the anterior laxity and the pivot-shift test than the single-bundle procedure, while there may be no significant differences in the other clinical evaluations and the intraoperative and postoperative complications between the 2 procedures.

Study Design

Cohort study; Level of evidence, 2.

Methods

Three hundred and twenty-eight patients with unilateral ACL reconstruction using hamstring autografts were divided into 2 groups. The first 157 consecutive patients underwent single-bundle reconstruction and the remaining 171 patients underwent anatomic double-bundle reconstruction. Concerning all background factors, there were no statistical differences between the 2 groups. Each patient was examined 2 years after surgery.

Results

No serious complications were experienced in either group. The anterior laxity was significantly less in the double-bundle reconstruction (mean, 1.2 mm) than in the single-bundle reconstruction (mean, 2.5 mm). In the pivot-shift test, the double bundle (+ indication 16%; ++, 3%) was significantly better than the single bundle (+ result, 37%; ++, 12%). The mean Lysholm score averaged 96.5 points’ and 97.3 points in single-bundle and double-bundle reconstructions, respectively, while the International Knee Documentation Committee evaluation showed that 90 and 110 patients, respectively, were evaluated as rank A (no significant difference between groups). There were no significant differences in the other clinical evaluations and the complications between the 2 procedures.

Conclusions

The postoperative anterior and rotational stability after the anatomic double-bundle ACL reconstruction was significantly better than that after the single-bundle reconstruction, although there were no significant differences between the 2 Procedures concerning the complications and the clinical evaluations.
Criminal Justice Graduate Programs at the Beginning of the 21st Century
Authors: Sever Brion , Coram Gregory , Meltzer Gwen
Published: May 2008

The needs of students seeking graduate degrees in criminal justice have shifted significantly over the past few decades, and this shift has been in conjunction with the changes to the field of criminology and criminal justice. Indeed, criminal justice graduate students today must not only master criminological theory, research, and administrative policy but also need computer and writing skills, as well as exposure to race, gender, and ethical issues. This study examines the focus that modern-day criminal justice graduate programs place on these areas by reviewing their curricula. Specifically, the authors examined 118 criminal justice masters programs that had curricula online during the spring and summer semesters of 2004. They found that the programs' curricula continue to place strong emphasis on traditional courses such as research, theory, and criminal justice administration, while placing less emphasis on courses centering on race, gender, ethics, computer applications, and comparative criminal justice.
Child Abduction, AMBER Alert, and Crime Control Theater
Authors: Griffin Timothy , Miller Monica K.
Published: May 2008

Intense interest in disturbing child abductions by the mass media, public safety organizations, and the public has helped sustain a socially constructed mythology and sporadic “moral panic” about the presumed pervasiveness of this threat to children. The result has often been reactionary “memorial” legislation enacted in response to sensational cases. A recent example is the America's Missing Broadcast Emergency Response (AMBER) Alert system, which is designed to interrupt serious child kidnappings in progress by soliciting citizen tips to help officials quickly rescue victims. Drawing on available empirical evidence and theoretical considerations, the authors contend that AMBER Alert has not achieved and probably cannot achieve the ambitious goals that inspired its creation. In fact, AMBER Alert is arguably an example of what could be called crime control theater. It is a socially constructed “solution” to a socially constructed problem, enabling public officials to symbolically address an essentially intractable threat. Despite laudable intentions, AMBER Alert exemplifies how crime control theater can create unintended problems, such as public backlash when the theatrical policy fails and a distorted public discourse about the nature of crime. Considerations for the future of AMBER Alert in particular, and the concept of crime control theater in general, are discussed.
A Qualitative Assessment of Registered Female Sex Offenders
Authors: Vandiver Donna M. , Dial Kelly Cheeseman , Worley Robert M.
Published: May 2008

In this study, the effect that the sex offender registry has had on female sex offenders in two states is explored. In-depth personal interviews were conducted with nine registered female sex offenders from Illinois and Texas. Questions were asked about the arrest that led to registration and the effect that sex offender registration statutes have had on their lives. Braithwaite's crime, shame, and reintegration theory was relied on to assess the extent to which the processes described in his theory occurred in this sample. The focus of many of the questions included whether the women were able to reintegrate into their communities or if they were stigmatized. It was found that every respondent reported at least one negative effect on her life as a result of being identified on the public registry. Also, many of the stigmatization processes described by Braithwaite were applicable to the interviewed women.
Federal Personnel Management Reform
Authors: Brook Douglas A. , King Cynthia L.
Published: May 2008

In what ways are current civil service reform efforts similar to and different from the qualities that characterize the Civil Service Reform Act of 1978 (CSRA)? These issues are explored by examining the new personnel authorities granted to the Department of Homeland Security (DHS) and to the Department of Defense (DoD) in the National Security Personnel System (NSPS). In many respects, current reforms preserve some of the ideas behind CSRA or they derive from the authorities included in the CSRA. In other respects, current reform departs from the CSRA model and new ideas related to enactment, design, and implementation of civil service reform have emerged. Furthermore, a new argument emerged in DHS and NSPS that had never before appeared in any public discourse on personnel management reform: the link between federal personnel management policy and national security.
Are Portland's Smart Growth Policies Related to Reduced Automobile Dependence?
Authors: Jun Myung-Jin
Published: May 2008

This study evaluates how successful smart growth policies in Portland, best known for its smart growth policies such as the urban growth boundary, extensive public transit service, and transit-oriented developments along the transit corridors, are in achieving one of their policy objectives, a reduction of automobile dependence. Empirical evidence reveals that more diversified land use in neighborhoods, more extensive provision of public transit service, and decreasing accessibility to freeway interchanges were associated with fewer choices of driving alone, while making settlements compact via the urban growth boundary and transit-oriented developments has no clear relationship with reducing the choice to drive alone. Empirical analyses also suggest that provision of public transit service and mixed land use implemented at residential zones (origins) were more effective in reducing automobile dependence than those implemented at places of work (destinations).
Games for traffic education: An experimental study of a game-based driving simulator
Authors: Backlund Per , Engström Henrik , Johannesson Mikael , Lebram Mikael
Published: May 2008

In this article, the authors report on the construction and evaluation of a game-based driving simulator using a real car as a joystick. The simulator is constructed from off-the-shelf hardware and the simulation runs on open-source software. The feasibility of the simulator as a learning tool has been experimentally evaluated. Results are reported from an experimental study of games and traffic safety performed in an advanced gaming environment. During car simulator sessions, the authors collected data about different traffic safety variables, such as speed, headway distance, and lane change behavior, from 70 participants. The data were analyzed to investigate possible individual learning effects and differences between groupings of participants. The experiment shows clear, positive, individual learning effects for all traffic safety variables analyzed. The authors also made a qualitative analysis of the participants’ perception of the simulator as a learning tool. From the results, it is concluded that a game-based simulation can be used to enhance learning in driving education.
Behavioral Parent Training in Child Welfare: Maintenance and Booster Training
Authors: Van Camp Carole M. , Montgomery Jan L. , Vollmer Timothy R. , Kosarek Judith A. , Happe Shawn , Burgos Vanessa , Manzolillo Anthony
Published: May 2008

Previous research has demonstrated the efficacy of a 30-hr behavioral parent training program at increasing skill accuracy. However, it remains unknown whether skills acquisitions are maintained on a long-term basis. Few studies have evaluated the maintenance of skills learned during behavioral parent training for foster parents. The purpose of this study is twofold: (a) to assess skill maintenance 8 to 35.5 months following the initial 30-hr training program and (b) to evaluate whether a 6-hr booster training would raise caregivers' skill performance to levels similar to those observed during posttests of the initial training. Overall results show partial maintenance of skills over time and positive effects of booster training for skills that had not been maintained. Results also show variability in individual participant and individual skill scores during various phases of the analysis, suggesting idiosyncratic differences with regard to initial training, maintenance, and booster training.
Trends in Racial Disparities Among the Elderly for Selected Procedures
Authors: Basu Jayasree , Mobley Lee R.
Published: May 2008

The authors examine trends over 1997-2001 in racial or ethnic disparities in the utilization of three costly, referral-sensitive procedures among the elderly—coronary artery bypass grafting (CABG), percutaneous transluminal coronary angioplasty (PTCA), and hip/joint replacement. Using a multivariate framework, they undertake a simultaneous examination of the relationships between patient, local area context, and health systems on these admission types after comparing them to a control group. This period spans the implementation of the Balanced Budget Act and a major Department of Health and Human Services initiative to reduce disparities in cardiovascular and other diseases. Findings suggest increasing disparities for African Americans relative to Whites in their lower utilization of CABG and PTCA over time, and increasing disparities in the utilization of hip/joint replacement among other races' relative to Whites. The authors find that racial or ethnic disparities in use of referral-sensitive procedures did not narrow over 1997-2001.
Evaluation's Second Act
Authors: Preskill Hallie
Published: May 2008

Imagine a world where evaluation is a social epidemic . . . where individuals, groups, organizations, and communities are constantly learning about and from evaluations. The author believes that we are well on our way to creating a “global cascade” of evaluative thinking and practice. Evidence of this phenomenon can be seen in the field's increasing commitment to evaluation capacity building and participatory evaluation approaches and the expanding applications of technology for accessing and disseminating information. If the old saying is “The second act is the best” then we might ask ourselves, “How can evaluation realize its potential for making a difference in our increasingly complex and changing world?” The author argues that addressing today's critical evaluation theory, practice, and policy issues requires us to understand the ways in which evaluation facilitates learning, how evaluators can maximize learning from and about evaluation, and what it would mean if the evaluation profession was a sustainable learning community.
Random Assignment and Informed Consent
Authors: Walker Robert , Hoggart Lesley , Hamilton Gayle
Published: May 2008

Although random assignment is generally the preferred methodology in impact evaluations, it raises numerous ethical concerns, some of which are addressed by securing participants' informed consent. However, there has been little investigation of how consent is obtained in social experiments and the amount of information that can be conveyed—and absorbed—prior to consent. This article reports on the implementation of the Employment Retention and Advancement (ERA) program, a large social experiment in the United Kingdom. Procedures to elicit informed consent were generally scrupulously followed, but even so many participants appeared to have only limited understanding of the experiment and their involvement in it. The reasons for this are articulated and recommendations are made to help ensure, to the extent possible, that potential random assignment study participants adequately understand their situation and their choices.