bluuebunny/crossref_metadata_2025 huggingface dataset:
Similarities and Differences Across the Factors Associated with Women’s Self-employment Preference in the Nordic Countries
Authors: Arenius Pia , Kovalainen Anne
Published: January 2006

The trend in women’s self-employment appeared to be upward in the 1980s and 1990s, but women are still less likely than men to start new businesses. The economic growth potential in most industrialized countries is gendered, and with lack of paid employment opportunities, more hopes are targeted towards women’s entrepreneurship. We will explore women’s self-employment preferences across Scandinavian countries,1 and the influence and importance of societal and individual factors affecting self-employment preferences and their similarities and differences. Perception of self-employment skills arises across the countries as the most salient factor predicting self-employment preference. The multivariate models differ across the countries, thus challenging the existence of a universal Scandinavian model that explains the entrepreneurial activities of women. This article makes two contributions. First, we show that gender has become a key element in new firm formation activities. Second, we contribute to entrepreneurial theories by demonstrating similarities and differences across the countries and adding the importance of structural issues for explaining gender and entrepreneurial activities.
Broadband Divide Among SMEs
Authors: Arbore Alessandro , Ordanini Andrea
Published: January 2006

While the digital gap between large and small firms is a fairly well-known phenomenon, this article focuses on the divide within SMEs. Specifically, the aim is to analyse factors that may explain the differences in broadband adoption among SMEs and to explore their significant interrelations. The investigation relies on a two-step procedure: first, using a tree-based technique, relevant variables and interactions are explored; then, through a binomial logistic regression, their impact on broadband diffusion is estimated and tested. Findings confirm that the relative size of the company (a proxy for firm’s internal resources) is still relevant among SMEs; in addition, the geographical area where SMEs are located (environmental resources) can act as a further obstacle especially for the smaller companies of the sample; finally, specific ICT organizational strategies - namely the outsourcing decisions - proved to be an important mitigating factor for size and location-based broadband disadvantages.
Determining Indications for Care Common to Competing Guidelines by Using Classification Tree Analysis: Application to the Prevention of Venous Thromboembolism in Medical Inpatients
Authors: Bosson Jean-Luc , Labarere Jose
Published: January 2006

Background. Substantial variations have been reported in the advice given by competing guidelines addressing the same clinical problem. Objective. This study aimed to assess the usefulness of classification tree analysis in comparing competing guidelines. Method. The authors implemented a classification tree–growing algorithm on cross-sectional data from 818 patients to determine indications for prophylactic heparin treatment common to 4 competing guidelines disseminated between 1998 and 2000 and addressing the prophylaxis of venous thromboembolism in medical inpatients. Results. The resulting classification tree involved 10 terminal nodes. Its mean accuracy estimated by performing 10-fold cross-validation was 82% (s = 3). The guidelines consistently supported prophylactic heparin treatment for 5 indications: a previous episode of deep vein thrombosis or pulmonary embolism, recent paralysis of lower limb(s), congestive heart failure with one or more risk factors, recent myocardial infarction, and malignancy with one or more risk factors. These indications involved 257 patients (31.4%) and were supported by robust scientific evidence. Deep vein thrombosis was detected in 27 of these patients (10.5%). Two consistent negative indications involved 347 patients (42.4%). Deep vein thrombosis was detected in 9 of these patients (2.6%). Three indications involving 214 patients (26.2%) were discordant over the 4 guidelines. Conclusion. Classification tree analysis of real patient data is a useful strategy to identify indications common to competing guidelines. These indications should be considered for inclusion when updating guidelines. The findings of recently completed randomized trials have partly resolved the disagreement among the 4 guidelines. This approach may be helpful when developing new guidelines or for identifying topics warranting further complementary clinical trials.
Anterior Shoulder Stabilization in Collision Athletes
Authors: Rhee Yong Girl , Ha Jeong Han , Cho Nam Su
Published: January 2006

Background

Collision athletes are reported to be at high risk for redislocation after anterior stabilization of shoulder instability. Some authors have suggested that arthroscopic stabilization produces results similar to those of open stabilization.

Purpose

To evaluate the results of anterior shoulder stabilization in collision athletes and to compare the clinical results between the arthroscopic and open methods.

Hypothesis

Open stabilization might produce better results than does arthroscopic stabilization in collision athletes.

Study Design

Cohort study; Level of evidence, 4.

Methods

Forty-eight shoulders of 46 collision athletes were enrolled for this study. The mean age of the patients at the time of surgery was 20 years, and the mean follow-up period was 72 months (range, 30-136 months). Sixteen shoulders underwent arthroscopic stabilization; 32 shoulders had open repairs.

Results

Visual analog scale, Rowe, and Constant scores improved after surgery, but no statistically significant difference was found between the arthroscopic and open repair groups. Thirty-seven athletes (83%) returned to near-preinjury sports activity levels (90% recovery) after operation. Two patients (4%) had subluxation and 6 (12.5%) had redislocation after surgery. The number of shoulders with postoperative subluxation or dislocation was 4 (25%) in the arthroscopic group and 4 (12.5%) in the open group (P = .041). Revision surgery was performed on 5 shoulders (10.4%).

Conclusions

There were 8 (16.5%) instances of postoperative instability among the collision athletes studied. The arthroscopic group yielded a higher failure rate than did the open group. The authors believe open stabilization to be a more reliable method for anterior shoulder instability in collision athletes.
Incidence of Injuries in Elite French Youth Soccer Players
Authors: Le Gall Franck , Carling Christopher , Reilly Thomas , Vandewalle Henry , Church Julia , Rochcongar Pierre
Published: January 2006

Background

Research on age-related injury incidence in elite youth soccer is needed to identify high-risk groups.

Purpose

To investigate the incidence of soccer-related injuries in elite French youth players based at the Clairefontaine Football Center.

Study Design

Cohort study (Prevalence); Level of evidence, 1.

Methods

Injuries sustained by players in the younger than 14-, 15-, and 16-year-old age groups during 10 seasons were diagnosed and documented by a sports physician according to type, location, severity, the date the injury occurred, and playing position.

Results

Altogether, 1152 injuries were documented across all age groups with 69.1% and 30.9% sustained during training and matches, respectively. A total of 4.8 injuries per 1000 hours’ exposure time were recorded and 11.2 and 3.9 injuries per 1000 hours for matches and training, respectively. There was no significant difference in injury frequency between age groups. The youngest group sustained more training injuries (P < .05) and osteochondroses (P < .05) and fewer match injuries than did the oldest group. Injury incidence varied throughout the season, peaking in September in all groups. The majority of injuries lasted less than 1 week (60.2%), contusions were the predominant injury type (30.6%, P < .05), and the upper leg was the site most often injured (24.5%, P < .05).

Conclusion

Those players younger than 14 years incurred more injuries in training and sustained more growth-related overuse disorders. Older players were more often injured during matches. Injury incidence and the frequency of overuse disorders were highest early in the season.
Foretelling Pathology
Authors: Cryle Peter
Published: January 2006

This paper examines a number of French middle-brow novels, usually called at the time romans de murs, from the period 1880–1910. It shows how, in these stories, doctors are shown to foretell the course of narrative through the diagnosis of certain pathologies, especially psychosexual ones. These pathologies are thus represented as implacable narrative programmes. In effect, most of these novels renounce the standard fictional resources of intrigue and suspense in favour of the relentless working out of their initial prognosis. The authority of medical discourse is therefore not just confirmed and disseminated: it is elaborated as fatality in the very terms of the novel.
A Large Sample Evaluation of a Court-Mandated Batterer Intervention Program: Investigating Differential Program Effect for African American and Caucasian Men
Authors: Buttell Frederick P. , Carney Michelle Mohr
Published: January 2006

Objective: The purpose of the present study was to (a) evaluate a 26-week batterer intervention program by investigating changes in psychological variables related to abuse (i.e., truthfulness, violence, lethality, control, alcohol use, drug use, and stress coping abilities) between pretreatment and posttreatment assessments in a large sample of men involuntarily placed in treatment and (b) investigate the differential effectiveness of this same batterer intervention program for African American and Caucasian batterers. Method: The study employed a secondary analysis of 850 treatment completers. Results: The findings of this study suggest that the court-ordered batterers comprising this sample demonstrate significant changes in the desired direction on psychological variables related to domestic violence, as a result of participation in a court-mandated treatment program, with no significant difference in terms of magnitude of change on these same psychological variables between African American and Caucasian batterers. Conclusion: Implications of the findings for social workers were explored and discussed.
Psychodynamic Psychotherapy: An Effectiveness Study
Authors: Roseborough David J.
Published: January 2006

Objective: Both the National Institute of Mental Health and the American Psychological Association have called upon psychodynamic practitioners to start demonstrating their outcomes. This effectiveness study attempted to begin to answer these calls. Method: The study was a secondary analysis of data from a multidisciplinary, psychodynamic mental health clinic. It used a single-group, within-subjects longitudinal design. The psychometrically validated Outcome Questionnaire was used as a measure of change. A linear mixed and random effects model was used to analyze the data. The aims of this study were (a) to look at whether patients improve and (b) if so, at what variables moderate outcome. Results: Findings suggest that psychodynamic treatment, provided within this practice configuration, is effective over time, producing moderate effect sizes, and points to the particular importance of the first 3 months. Conclusions: Findings suggest a common course of recovery, with some between-group variability.
Rap-music Attitude and Perception Scale: A Validation Study
Authors: Tyson Edgar H.
Published: January 2006

Objective: This study tests the validity of the Rap-music Attitude and Perception (RAP) Scale, a 1-page, 24-item measure of a person’s thoughts and feelings surrounding the effects and content of rap music. The RAP was designed as a rapid assessment instrument for youth programs and practitioners using rap music and hip hop culture in their work with young people, their families, and their communities. Method: The factor structure validity, criterion-related validity, and internal consistency reliability of the RAP was assessed using a convenience sample of 605 young (M = 20.22 years, SD = 2.8) college students. Results: Multiple groups method and structural equation modeling analyses confirmed the three-factor model (empowerment, violent-misogynistic, and artistic-esthetic) of the RAP. Reliability and criterion-related validity results were also good. Conclusions: The RAP has sound psychometric properties, and its utility as a research and assessment tool for scholars and practitioners is promising.
Parent-Centered Intervention: A Practical Approach for Preventing Drug Abuse in Hispanic Adolescents
Authors: Tapia Maria I. , Schwartz Seth J. , Prado Guillermo , Lopez Barbara , Pantin Hilda
Published: January 2006

Objective: The objective of the present article is to review and discuss Familias Unidas, an empirically supported, family-based, culturally specific drug abuse and HIV prevention intervention for Hispanic immigrant adolescents and their families. Method: The authors focus on engagement and retention as well as on intervention delivery. Conclusions: The present article serves as a guide for social workers and mental health practitioners in carrying out effective family-based adolescent substance use and HIV preventive interventions. Recommendations for and challenges to implementing the intervention in practice-based settings are discussed.
School-Based Prevalence Assessment of the Need for Mental Health Services: Survey Development and Pilot Study
Authors: Cohen Edward , Angeles Joe
Published: January 2006

Objective: The School Site Needs Assessment instrument was designed to provide a multidimensional environmental scan of potential need for mental health services in classrooms and schools. Method: Items of the instrument covering various academic, social, and mental health domains were developed based on analysis of previous case management contact data and input from stakeholders. The teacher-response instrument was piloted with a convenience sample of 85 classrooms in seven schools. Results: 43% of students were observed by teachers to have at least one problem that could likely result in referral to a case manager. Frequently counted problems included “disruptive in class” (14% of students), “failing” risk (13% of students), and “hyperactive”-related behaviors (10% of students). Conclusions: The School Site Needs Assessment can assist school social workers in assessing the environmental mental health context of students and classrooms from the important perspective of teachers, leading to classroom and school site interventions.
Imagined futures, present lives
Authors: Wildermuth Norbert , Dalsgaard Anne Line
Published: January 2006

The article is focused thematically on the uses and meanings of media for (some) young people in Recife, a million-inhabitant city in the northeast of Brazil. The article brings together the perspective of Anne Line Dalsgaard, a long-term anthropological field researcher who is familiar with the everyday lives and social conditions for growing up in Recife, and the findings of a short-term, interview- and observation-based media ethnographic study, conducted by Norbert Wildermuth. The concept of imagination as potentially both an enabling and a limiting practice in the consumption of media is discussed centrally in this attempt to contribute to an empirically grounded understanding of the role that media play for youth in their striving to ‘find a place in life’. In the empirical context presented in the article, imaginations, expanded and circulated by a globalized media circuit, are appropriated and interpreted locally and under particular socio-economic conditions.
Emancipation enlargement and the acquisition of autonomy by young people in Catalonia
Authors: Merino Rafael , Garcia Maribel
Published: January 2006

This article analyses family emancipation and the transition from school to work in the context of transition to adulthood in Catalonia, and discusses some central issues of youth sociology. The data used have been provided by the 2002 Catalan Young People Survey (Casal et al.,2004), carried out in 2002 and 2003, which was commissioned by the Catalan government and managed by the Education and Work Research Group (Autonomous University of Barcelona). The survey was done with a representative sample of 2000 young people from Catalonia aged between 15 and 29. This article explains the postponement of leaving home, the new degrees of autonomy managed by young people and the relationship between the age of emancipation and the complexity of transition from school to work. Finally, we highlight some conclusions with regard to the theoretical framework and policy-making issues.
Courting risk
Authors: Dobson Stephen , Brudalen Rita , Tobiassen Hilde
Published: January 2006

Youth have been understood as progressing through formal education towards entrance into university or other forms of higher education. But, what of the informal curriculum and the manner in which youth are obsessed by it as a source of formative experiences? This article takes as an example of this the grisefest (pig party) of Norwegian youth in the final year of high school. Through examples such as these our goal is to develop a framework to understand how youth cultures, as sources of education, are ultimately connected with the desire to ‘court risk’.Our conclusion is that, through such activities, we witness what is called ‘learning by doing’, where self-formation ( bildung) and the gaining of a certain competence, not necessarily of a deviant character, are important elements and based upon the role of personal experiences. This article is a follow-up to our project, entitled Overcoming Nihilism Through Planned Normlessness. The Experience of Norwegian High School Youth (Dobson et al., 2003). We continue to develop our views based on Nietzsche’s pedagogy by focusing not upon nihilism, but risk. Accordingly,‘risk’becomes an important additional category in our developing understanding of Nietzsche’s pedagogy.
Social Theory’s Methodological Nationalism
Authors: Chernilo Daniel
Published: January 2006

The equation between the concept of society and the nation-state in modernity is known as methodological nationalism in scholarly debates. In agreement with the thesis that methodological nationalism must be rejected and transcended, this article argues that we still lack an understanding of what methodological nationalism actually is and, because of that, we remain unable to answer the substantive problem methodological nationalism poses to social theory: how to understand the history, main features and legacy of the nation-state in modernity. The first section of the article reconstructs the origins of the critique of methodological nationalism in the 1970s and differentiates between its logical and historical versions. It then critically reviews the most salient critique of methodological nationalism in contemporary social theory, that of Ulrich Beck. The final part of the article assesses the thesis of social theory’s immanent methodological nationalism by demonstrating how social theory’s equivocations towards the nation-state only mirror the nation-state’s own ambivalence within modernity. It is shown that social theory’s ambivalent attempts at conceptualizing the nation-state reflect the actual ambivalence of the position of the nation-state in modernity: its historical opacity, its sociological uncertainty and its normative ambiguity.
Self-Experience in the Theme Park of Radical Action?
Authors: Blühdorn Ingolfur
Published: January 2006

In accordance with the established view that the new social movements since the late 1960s have always pursued an agenda of comprehensive societal change, the new wave of movement activism since the late 1990s has widely been interpreted as evidence of the emergence of a new global movement for a radically different society. A critique of the one-sided reliance in social movement research on traditional actor-centred approaches leads to a systems-centred conceptualization of late-modern society, and via the diagnosis of its particular dilemmas, to the interpretation of contemporary social movements as a vital resource for the stabilization of the socioeconomic order of democratic consumer capitalism. As an addition to the existing social movement theories, the suggested approach contributes to a more complex understanding of non-conventional forms of political articulation and participation.
Leadership as De-paradoxification: Leading New Drug Development Work at Three Pharmaceutical Companies
Authors: Sundgren Mats , Styhre Alexander
Published: January 2006

Traditionally, the role of leadership has received little attention in the literature dealing with organizational creativity. This article describes a study of the role of leadership and its implications for organizational creativity in pharmaceutical research and new drug development. Creative work in new drug development is to a large extent riddled with a series of paradoxes and non-linear causality and thus needs to be dealt with using leadership practices which help researchers overcome what would seem to be paradoxical. The study makes use of Niklas Luhmann’s concept of de-paradoxification to examine a number of opposing objectives and concepts which influence leadership practice during creative and innovative work. De-paradoxification, in this sense, does not mean solving the perceived paradox but making it manageable. This study is based on a series of interviews concerning how managers and scientists at three pharmaceutical companies conceive of leadership in creative environments. This article pinpoints the importance as well as the influence of leadership in both R&D settings, and in creative milieus in general, concluding that leadership is important in creative settings, but that it should be practiced by other means than those used in less complex environments. Consequently, more systematic research as well as more critical evaluations of the leadership literature are needed.
Investigations of andesitic volcanic debris terrains: Part I — Geophysical
Authors: Gay Derek A. , Morgan Frank D. , Sogade John A. , Vichabian Yervant , Reppert Philip , Wharton A. E.
Published: January 2006

This article contains the findings of geophysical investigations conducted at the site of the proposed international airport at Melville Hall, Commonwealth of Dominica, West Indies. The main geophysical method used was seismic refraction; additionally, ground-penetrating radar, resistivity sounding, and resistivity tomographic imaging were performed at some of the sites, but only the results of the seismic refraction and electrical resistivity sounding contributed to the development of the model presented. Analysis of the seismic data shows a gradual increase in velocity with depth, for which a model has been determined. Ancillary models or predictions of porosity, density, and natural compaction with depth are given, based on the basic seismic model. The seismic velocity model allows an engineer with a topographic map of the area to predict the volume of rock/soil in each rippability class and to project the rate of ripping. The results of the 1D resistivity soundings strongly suggest a nearly homogeneous material with resistivity variations that can be explained by moisture and low-level lithological variations. Therefore, based on integrated seismic and resistivity results, our model is a thick ash/boulder conglomerate with velocity increasing with depth, mainly from overburden stress compaction. In other words, the material at depth is not well-cemented rock. As the overburden stress is removed, the material essentially expands and loosens to produce a lower seismic velocity, similar to present surface conditions. The soil/rock can therefore be removed with little or no ripping or blasting.
Quartic reflection moveout in a weakly anisotropic dipping layer
Authors: Grechka Vladimir , Pech Andrés
Published: January 2006

Deviations of P-wave reflection traveltimes from a hyperbola, called the nonhyperbolic or quartic moveout, need to be handled properly while processing long-spread seismic data. As observed nonhyperbolic moveout is usually attributed to the presence of anisotropy, we devote our paper to deriving and analyzing a general formula that describes an azimuthally varying quartic moveout coefficient in a homogeneous, weakly anisotropic medium above a dipping, mildly curved reflector. To obtain the desired expression, we consistently linearize all quantities in small stiffness perturbations from a given isotropic solid. Our result incorporates all known weak-anisotropy approximations of the quartic moveout coefficient and extends them further to triclinic media. By comparing our approximation with nonhyperbolic moveout obtained from the ray-traced reflection traveltimes, we find that the former predicts azimuthal variations of the quartic moveout when its magnitude is less than 20% of the corresponding hyperbolic moveout term. We also study the influence of reflector curvature on nonhyperbolic moveout. It turns out that the curvature produces no quartic moveout in the reflector strike direction, where the anisotropy-induced moveout nonhyperbolicity is usually nonnegligible. Thus, the presence of nonhyperbolic moveout along the reflector strike might indicate effective anisotropy.
Abnormal transmission attenuation and its impact on seismic-fracture prediction — A physical modeling study
Authors: Luo Mu , Arihara Norio , Wang Shangxu , Di Bangrang , Wei Jianxin
Published: January 2006

Fracture-induced anisotropy can lead to observable azimuthal variations of seismic attributes that then can be used for characterizing a fracture system. Unfortunately, abnormal transmission losses along raypaths also can result in similar azimuthal variations leading to uncertainty in such fracture determination. Using a physical model containing gas-filled fractures, we investigate the impact of abnormal transmission loss on fracture detection from ultrasonic data in a laboratory setting. Recorded reflection amplitudes and traveltimes are used to study ultrasonic responses to the presence of the gas-filled fractures and to understand observed azimuthal attribute anomalies. Experimental results from this study highlight the pitfalls in using azimuthal attribute variations as indicators of the presence of fractures when abnormal transmission attenuation is significant.
Applying reflection tomography in the postmigration domain to multifold ground-penetrating radar data
Authors: Bradford John H.
Published: January 2006

Acquisition and processing of multifold ground-penetrating radar (GPR) data enable detailed measurements of lateral velocity variability. The velocities constrain interpretation of subsurface materials and lead to significant improvement in image accuracy when coupled with prestack depth migration (PSDM). Reflection tomography in the postmigration domain was introduced in the early 1990s for velocity estimation in seismic reflection. This robust, accurate method is directly applicable in multifold GPR imaging. At a contaminated waste facility within the U.S. Department of Energy's Hanford site in Washington, the method is used to identify significant lateral and vertical velocity heterogeneity associated with infilled waste pits. Using both the PSDM images and velocity models in interpretation, a paleochannel system that underlies the site and likely forms contaminant migration pathways is identified.
Ground-penetrating radar tomography for soil-moisture heterogeneity
Authors: Hanafy S. , al Hagrey S. A.
Published: January 2006

Many ground-penetrating radar (GPR) studies incorporate tomographic methods that use straight raypaths for direct model reconstruction, which is unrealistic for media with gradually changing petrophysics. Ray-bending algorithms can sometimes lead to unreliable resolution, especially at interfaces of abrupt dielectric changes. We present an improved GPR tomography technique based on a combination of seismic tomographic methods and a finite-difference solution of the eikonal equation. Our inversion algorithm uses velocity gradient zones and bending rays that represent realistic geology in the subsurface. We tested the technique on theoretical and experimental models with anomalous bodies of varying saturations and velocity and applied it to data from a GPR field experiment that analyzed the root zones of trees. Synthetic results showed that the resolution of our technique is better than that of published methods, especially for local anomalies with sharp velocity contacts. Our laboratory experiments consisted of four objects buried in sand with various water saturations. The GPR tomogram could map the objects and determine their degree of saturation. The velocities are compatible with those of the complex refraction index method; their relationship to the water content fits a previously published empirical equation. Our original field experiment around a poplar tree could map the heterogeneous subsurface and distinguish a central low velocity beneath the tree from the peripheral negative anomaly of a refill. This zone reflects the whole root zone and is caused by its bulk water content of both the organic root network and its surrounding soils.
Leveling aerogeophysical data using a moving differential median filter
Authors: Mauring Eirik , Kihle Ola
Published: January 2006

We describe a new technique that can be used to level data collected along regular and irregular line patterns with or without tie-line control. The technique incorporates a moving differential median filter to minimize line-level errors, to level survey-line data, and to microlevel data with no tie-line control. This overcomes the problem of standard leveling methods that lose their effectiveness with irregular flight patterns. To validate the method, we use it to level very-low-frequency (VLF) electromagnetic (EM) data from a helicopter survey where flight lines are parallel. Leveling is also performed on a set of vintage aeromagnetic data from the North Sea, gathered from nonparallel flight lines. Results show that the differential median filter leveling technique is superior to the standard leveling method because it results in fewer line errors and less distortion of high-wavenumber anomalies when processing irregular survey lines, making the method suitable for a wide variety of data sets.
Mapping 3D salt using the 2D marine magnetotelluric method: Case study from Gemini Prospect, Gulf of Mexico
Authors: Key Kerry W. , Constable Steven C. , Weiss Chester J.
Published: January 2006

The dominant salt body at Gemini Prospect, Gulf of Mexico, has been analyzed by seismic methods, revealing a complex 3D salt volume at depths 1 to 5 km beneath the mud line. Because of the high contrast in electrical conductivity between the salt and surrounding sediments, Gemini is an attractive target for electromagnetic interrogation. Using a broadband magnetotelluric (MT) sensor package developed at the Scripps Institution of Oceanography, data in the period band of 1 to 3000 s were collected at 42 sites in a series of profiles over Gemini, one of which was directly over a linear ridgelike salt feature striking roughly northwest–southeast and another orthogonal to it. These two profiles reveal that the strongest MT response arises when the electric field is oriented northeast–southwest. We test the suitability of 2D inversion of these data for recovering the true salt structure by examining inversions of both actual data and synthetic 3D MT responses derived from the seismically inferred salt volume. Occam inversions of the northeast–southwest component result in resistivity images that generally agree with the seismic data, whereas inversions of the complementary component yield significantly poorer fidelity. Disagreement is greatest (1–2 km) along the salt sides and base. Depth errors for top of salt are less than 500 m. Although thin, deep salt (<1 km thick at 5 km depth) is not well resolved, the inversions reveal a resistive basement and a shallow subseabed environment rich in electrical heterogeneity that is weakly, if at all, suggested by the seismic data. A notable exception is a correlation between a previously uninterpreted seismic reflector and the base of a shallow resistivity anomaly whose presence is consistent with gas accumulation near the hydrate stability zone.
Modeling wave generation by borehole orbital vibrator source
Authors: Nakagawa Seiji , Daley Thomas M.
Published: January 2006

An orbital vibrator source (OVS), a fluid-coupled shear-wave source, has many properties useful for crosswell, single-well, and borehole-to-surface imaging of both P- (compressional) and S- (shear) wave velocities of reservoir rocks. To this day, however, only a limited number of quantitative models have been developed to explain its properties. In this article, we develop both 2D and 3D models of an OVS, allowing us to examine source characteristics such as radiation patterns, frequency dependence of wave amplitudes, and guided-wave generation. These models are developed in the frequency-wavenumber domain using the partial wave expansion of the wavefield within and outside the borehole. The models predict many unique characteristics of an OVS, including formation-property-dependent vibrator amplitudes, uniform isotropic S-wave radiation pattern, and small tube-wave generation.
Interactive gravity inversion
Authors: Silva João B. C. , Barbosa Valéria C. F.
Published: January 2006

We have developed a new approach for estimating the location and geometry of several density anomalies that give rise to a complex, interfering gravity field. The user interactively defines the assumed outline of the true gravity sources in terms of points and line segments, and the method estimates sources closest to the specified outline to achieve a match between the predicted and observed gravity fields. Each gravity source is assumed to be a homogeneous body with a known density contrast; different density contrasts may be assigned to each source. Tests with synthetic data show that the method can be of use in estimating (1) multiple laterally adjacent and closely situated gravity sources, (2) single gravity sources consisting of several homogeneous compartments with different density contrasts, and (3) two gravity sources with different density contrasts of the same sign, one totally enclosed by the other. The method is also applied to three different sets of field data where the gravity sources belong to the same categories established in the tests with synthetic data. The method produces solutions consistent with the known geologic attributes of the gravity sources, illustrating its potential practicality.
Properties of surface waveguides derived from separate and joint inversion of dispersive TE and TM GPR data
Authors: Kruk Jan van der , Streich Rita , Green Alan G.
Published: January 2006

Pronounced dispersion of ground-penetrating radar (GPR) waves is observed at locations distinguished by thin surface layers of high-permittivity material (e.g., water-saturated soil). The dispersion characteristics depend on the permittivity and thickness of the effective surface waveguide and the permittivity of the material below it. We introduce a scheme for estimating the values of these parameters from dispersed transverse-electric (TE) and transverse-magnetic (TM) GPR data that is analogous to recently developed methods for analyzing dispersed Rayleigh waves recorded on multichannel seismic data. Our scheme involves calculating phase-velocity spectra, picking dispersion curves from the spectra, and then inverting the dispersion curves for the subsurface material properties by using a combined local- and global-minimization procedure. Application of this new scheme to synthetic and field data demonstrates its efficacy in providing the required physical property information. Where the surface layer is relatively distinct and uniform, inversions of the resulting high-quality dispersed TE data provide all required parameters. In more heterogeneous environments, joint inversions of the TE and TM data, which usually include information in different frequency ranges, may be required.
Stability analysis of velocity imaging of 2D multilayered structures through inverse reflected rays
Authors: Wang Tan K.
Published: January 2006

Inverse reflected rays are used to image velocities and interfaces in 2D multilayered media. Their direction cosines are specified from the receiver and the source, related respectively to the traveltime gradients of the common-source and common-receiver gathers. Based on the geometry of an inverse ray through the lowest layer, the velocity near the reflection point is derived from either an exact solution or a transcendental equation. For the transcendental equation, the velocity bounds and the imaging stability depend on the interface dips, and the incident angles upon the interface above the reflection point. The velocity imaging is stable or quasi-stable when the reflection point is located between the intersections of the inverse rays and the upper interface. Application of the technique to a discontinuous normal fault and a forearc basin show that most of the velocity imaging is stable. However, if the inverse reflected rays pass through steep interfaces, the fault plane or highly inhomogeneous media, the imaging is usually unstable because multivalued and incorrect velocities are generated. I conclude that the method is fast and capable of imaging seismic sections with poor quality when compared with prestack depth migration and reflection tomography.
Intellectual Property
Authors: Walker David A.
Published: January 2006

The Intellectual Property department in each issue of Geophysics provides U.S. patent abstracts, published patent abstracts of U.S. patent applications, and published abstracts filed under the Patent Cooperation Treaty (PCT).
North American Coral Snake Antivenin for the Neutralization of Non‐native Elapid Venoms in a Murine Model
Authors: Richardson William H. , Tanen David A. , Tong Tri C. , Betten David P. , Carstairs Shaun D. , Williams Saralyn R. , Cantrell Frank L. , Clark Richard F.
Published: January 2006

Objectives:
North American coral snake antivenin (CSAV; Wyeth Antivenin [Micrurus fulvius], equine origin) is approved for the treatment of coral snake envenomations in the United States. The coral snake is the only elapid that is native to North America, but envenomations from non‐native elapids are occurring more commonly in this country. This study was designed to evaluate the efficacy of CSAV in the neutralization of two exotic elapid envenomations: Naja naja (Indian cobra) and Dendroaspis polylepsis (black mamba).

Methods:
A randomized, blinded, placebo‐controlled murine model of intraperitoneal venom injection was employed. Venom potency was determined in preliminary dosing studies. Study animals then were divided into five groups: 1) N. naja venom + CSAV, 2) N. naja venom + 0.9% normal saline (NS), 3) D. polylepsis venom + CSAV, 4) D. polylepsis venom + NS, and 5) CSAV + NS. The venom dose was chosen to be twice the estimated LD 50. The amount of CSAV injected was ten times the amount necessary for neutralization of a 2 × LD50 dose of M. f. fulvius venom in a murine model. Statistical analysis included Fisher's exact and log‐rank testing to compare survival rates and times.

Results:
Preliminary studies estimated the venom LD50 to be 2.58 mg/kg and 0.45 mg/kg, respectively, for the N. naja and D. polylepsis. A significant difference was shown in comparison of survival times between CSAV–venom groups and normal saline–venom groups despite all animals in both treatment and control arms dying. Animals receiving CSAV and N. naja venom survived (mean ± SD) 24.4 ± 3.0 minutes, versus 17.8 ± 1.3 minutes in the control group (p < 0.001), whereas those receiving CSAV and D. polylepsis venom survived 203.8 ± 37.0 minutes versus 130.0 ± 42.6 minutes in the control group (p < 0.001). All animals in the CSAV + NS group survived to the conclusion of the study.

Conclusions:
When premixed with venom, CSAV increased survival time in a murine model of intraperitoneal N. naja and D. polylepsis venom injection. The clinical implications of this are unclear, given unchanged mortality rates.
Characteristics of Emergency Medicine Program Directors
Authors: Beeson Michael S. , Gerson Lowell W. , Weigand John V. , Jwayyed Sharhabeel , Kuhn Gloria J.
Published: January 2006

Objectives:
To characterize emergency medicine (EM) program directors (PDs) and compare the data, where possible, with those from other related published studies.

Methods:
An online survey was e‐mailed in 2002 to all EM PDs of programs that were approved by the Accreditation Council of Graduate Medical Education. The survey included questions concerning demographics, work hours, support staff, potential problems and solutions, salary and expenses, and satisfaction.

Results:
One hundred nine of 124 (88%) PDs (69.7% university, 27.5% community, and 2.8% military) completed the survey; 85.3% were male. Mean age was 43.6 years (95% confidence interval [CI] = 42.6 to 44.7 yr). The mean time as a PD was 5.7 years (95% CI = 4.9 to 6.5 yr), with 56% serving five years or less. The mean time expected to remain as PD is an additional 6.0 years (95% CI = 5.2 to 6.8). A 1995 study noted that 50% of EM PDs had been in the position for less than three years, and 68% anticipated continuing in their position for less than five years. On a scale of 1 to 10 (with 10 as highest), the mean satisfaction with the position of PD was 8.0 (95% CI = 7.2 to 8.3). Those PDs who stated that the previous PD had mentored them planned to stay a mean of 2.0 years longer than did those who were not mentored (95% CI of difference of means = 0.53 to 3.53). Sixty‐five percent of PDs had served previously as an associate PD. Most PDs (92%) have an associate or assistant PD, with 54% reporting one; 25%, two; and 9%, three associate or assistant PDs. A 1995 study noted that 62% had an associate PD. Ninety‐two percent have a program coordinator, and 35% stated that they have both a residency secretary and a program coordinator. Program directors worked a median of 195 hours per month: clinical, 75 hours; scholarly activity, 20 hours; administrative, 80 hours; and teaching and residency conferences, 20 hours; compared with a median total hours of 220 previously reported. Lack of adequate time to do the job required, career needs interfering with family needs, and lack of adequate faculty help with residency matters were identified as the most important problems (means of 3.5 [95% CI = 3.2 to 3.7], 3.4 [95% CI = 3.2 to 3.6], and 3.1 [95% CI = 2.9 to 3.3], respectively, on a scale of 1 to 5, with 5 as maximum). This study identified multiple resources that were found to be useful by >50% of PDs, including national meetings, lectures, advice from others, and self‐study.

Conclusions:
Emergency medicine PDs generally are very satisfied with the position of PD, perhaps because of increased support and resources. Although PD turnover remains an issue, PDs intend to remain in the position for a longer period of time than noted before this study. This may reflect the overall satisfaction with the position as well as the increased resources and support now available to the PD. PDs have greater satisfaction if they have been mentored for the position.
Cognitive Performance Following Modafinil versus Placebo in Sleep‐deprived Emergency Physicians: A Double‐blind Randomized Crossover Study
Authors: Gill Michelle , Haerich Paul , Westcott Kelli , Godenick Kristen L. , Tucker Jennifer A.
Published: January 2006

Objectives:
Modafinil has recently been approved for the treatment of shift work sleep disorder, making it potentially available for shift‐working emergency physicians. The authors' objectives were to determine whether modafinil improved cognitive performance of emergency physicians following overnight shifts and to record symptoms and subjective evaluations of the effect of modafinil on the participants.

Methods:
This was a randomized, double‐blind, placebo‐controlled crossover study that followed CONSORT guidelines. Participants were assigned to one of two study groups, with study sessions occurring at least seven weeks apart, and received either modafinil or placebo depending on their random allocation. Testing after night shifts included a coding task and an AX version of the Continuous Performance Task, both of which test cognitive function. Participants also completed visual analog scales for three subjective outcomes, and symptoms were elicited.

Results:
Modafinil facilitated performance on long interstimulus‐interval AX trials (F [1, 23] = 6.65, p = 0.1) and marginally reduced errors on AY trials in the Continuous Performance Task (F [1, 23] = 3.59, p = 0.07), suggesting facilitation of sustained attention, cognitive control, and working memory. Additionally, modafinil, compared with placebo, facilitated performance on the coding task at the first session. Subjective data from visual analog scales confirmed that modafinil increased perceived alertness during the simulated patient care sessions but worsened sleep onset when opportunities for sleep arose.

Conclusions:
Modafinil increased certain aspects of cognitive function and subjectively improved participants' ability to attend post–night‐shift didactic sessions but made it more difficult for participants to fall asleep when opportunities for sleep arose.
Lipid Rafts Mediate Ultraviolet Light‐induced Fas Aggregation in M624 Melanoma Cells
Authors: Elyassaki Walid , Wu Shiyong
Published: January 2006

Ultraviolet light (UV) induces aggregation of Fas‐receptor through a Fas‐ligand‐independent pathway. However, the mechanism of ultraviolet light‐induced Fas‐receptor aggregation is not known. In this report, we show that lipid rafts mediate ultraviolet light‐induced aggregation of Fas. Our data show that UV induces a redistribution of Fas‐receptor in a 25–5% Optiprep continuous gradient. The amount of Fas‐receptor is significantly increased in a gradient fraction that contain lipid rafts and is associated with an increase of FADD and caspase‐8. Our data also show that the active dimeric form of caspase‐8 (p44/p41) is increased in the lipid raft fraction. In addition, our data show that cholesterol, a major component of lipid rafts, is significantly reduced in only the lipid raft fractions after UV‐irradiation. However, ceramide, another major lipid raft component, is increased evenly in all gradient fractions after UV‐irradiation. These results suggest that UV alters the composition of major lipid raft components, which leads to the recruitment of Fas‐receptor and FADD, with subsequent activation of caspase‐8. Based on our results, we propose a novel mechanism by which UV induces apoptosis through a membrane lipid raft‐mediated signaling pathway.
Convergence of Higher Education and Economic Growth during the European Construction: A Contribution to the Cliometrics of Growth (EU-15)
Authors: Diebolt Claude , Jaoul-Grammare Magali
Published: January 2006

With the Treaty of Maastricht, European states committed themselves to the pathway of Economic and Monetary Union (EMU). Admission to EMU assumes respect for certain so-called ‘convergence criteria’. In spite of this joint determination to achieve harmonisation, education, one of the most important socio-economic fields, remains in the hands of the member states. With this as the point of departure, this article is aimed at checking whether the construction of Europe was accompanied by convergence in terms of per capita gross domestic product (GDP) and in terms of the development of higher education. Results show that depending on whether examination is performed on a stage-by-stage basis or for the entire study period, the development of higher education precedes or follows economic development.