bluuebunny/crossref_metadata_2025 huggingface dataset:
Ccm1 Regulates Microvascular Morphogenesis during Angiogenesis
Authors: Liu Huiling , Rigamonti Daniele , Badr Ahmed , Zhang Jun
Published: October 2010

Cerebral cavernous malformations (CCMs) are characterized by abnormally dilated intracranial capillaries that have a propensity to bleed. The development of some CCMs in humans has been attributed to mutations in CCM1 and CCM2 genes. In animal models, major cardiovascular defects caused by both gene mutations have been observed. However, the effects of the loss of Ccm function on the microvasculature in animal models are less defined. Using high-resolution imaging in vivo, we demonstrated that the loss of Ccm1 in zebrafish embryos leads to failed microvascular lumenization during angiogenesis due to impaired intraendothelial vacuole formation and fusion. No developmental changes during vasculogenesis and the initial stage of angiogenesis were observed, being in contrast to prior reports. In vivo zebrafish studies were further substantiated by in vitro findings in human endothelial cells that elucidated the biochemical pathways of CCM1 deficiency. We found that CCM1 regulates angiogenic microvascular lumen formation through Rac1 small GTPase. In summary, Ccm1 has been identified as a key angiogenic modulator in microvascular tubulogenesis. Additionally, the microvascular pathology observed in developing Ccm1 mutant zebrafish embryos mirrors that seen in human CCM lesions, suggesting that zebrafish might provide a superior animal model to study the pathogenesis of human CCM.
RCAN1 Regulates Vascular Branching during Xenopus laevis Angiogenesis
Authors: Fujiwara Masakazu , Hasebe Takashi , Kajita Mitsuko , Ishizuya-Oka Atsuko , Ghazizadeh Mohammad , Kawanami Oichi
Published: October 2010

Background/Aims:The mechanisms that regulate the size-related morphologies of various blood vessels from the aorta to capillary vessels are still poorly understood. In this study, we evaluate the involvement of regulator of calcineurin 1 (RCAN1), a regulatory protein in the calcineurin/NFAT signal transduction pathway, in vascular morphology to gain further insight into these mechanisms. Methods and Results: We first generated 2 types of vasculature in vitro from the same source of human umbilical vein endothelial cells by fibrin gel assay. We found that RCAN1 was significantly upregulated in large vessels with low branching frequencies when compared with small vessels with high branching frequencies. Next, to clarify whether RCAN1 regulates the branching of blood vessels in vivo, we injected RCAN1 mRNA into fertilized Xenopus laevis eggs. Overexpression of RCAN1 decreased the number of branching points that sprouted from intersomitic vessels during X. laevis angiogenesis. In addition, coexpression of calcineurin A, a target of RCAN1, could rescue RCAN1-suppressed vascular branching. Conclusions: These results provide in vivo evidence of RCAN1-regulated vascular branching which may play a role in the patterning of morphologically different vasculature.
Absence of the Adenosine A2A Receptor Confers Pulmonary Arterial Hypertension and Increased Pulmonary Vascular Remodeling in Mice
Authors: Xu M.H. , Gong Y.S. , Su M.S. , Dai Z.Y. , Dai S.S. , Bao S.Z. , Li N. , Zheng R.Y. , He J.C. , Chen J.F. , Wang X.T.
Published: October 2010

Background: Pulmonary arterial hypertension (PAH) is characterized by sustained elevation of pulmonary vascular resistance resulting from endothelial and smooth muscle cell dysfunction and collagen deposition in pulmonary vascular walls. In this study, we investigated the role of the adenosine A2A receptor (A2AR) in the development of PAH by determining the effect of genetic inactivation of A2ARs on pulmonary vascular remodeling in mice. Methods and Results: We characterized hemodynamic, histological and ultrastructural changes in pulmonary vascular remodeling in A2AR knockout (KO) mice compared with their wild-type (WT) littermates after exposure to normoxia and hypoxic conditions. After exposure to normoxia, compared to WT mice, A2AR KO mice displayed: (1) increased right ventricular systolic pressures and an elevated ratio of the right ventricle over left ventricle plus septum (Fulton index), (2) increased wall area and thickness as well as enhanced smooth muscle actin immunoreactivity in pulmonary resistance vessels, (3) increased proliferating cell nuclear antigen-positive cells in pulmonary resistance vessels and (4) increased smooth muscle cells hypertrophy and collagen deposition in the adventitia of pulmonary arteriole walls as revealed by electron microscope. By contrast, histological analysis revealed no features of hypertensive nephropathy in A2AR KO mice and there was no significant difference in systemic blood pressure, and left ventricular masses among the 3 genotypes. Furthermore, following chronic exposure to hypoxia, A2AR KO mice exhibited exacerbated elevation in right ventricular systolic pressure, hypertrophy of pulmonary resistance vessels and increased cell proliferation in pulmonary resistance vessels, compared to WT littermates. Thus, genetic inactivation of A2ARs selectively produced PAH and associated increased smooth muscle proliferation and collagen deposition. Conclusions: Extracellular adenosine acting at A2ARs represents an important regulatory mechanism to control the development of PAH and pulmonary vascular remodeling.
Inhibition of Inducible Nitric Oxide Synthase Promotes Vein Graft Neoadventitial Inflammation and Remodelling
Authors: Wu Junxi , Wadsworth Roger M. , Kennedy Simon
Published: October 2010

Background: Grafting veins into the arterial circulation causes endothelial damage and neointimal hyperplasia. However, the remodelling of vein grafts and the contribution of the endothelium is not well understood. Since nitric oxide (NO) has a crucial role in vascular function, we investigated the importance of NO synthases (NOSs) in vein graft re-endothelialization and remodelling in this study. Methods and Results: Mouse isogenic vena cava was grafted into the carotid artery. Progressive remodelling of the grafted veins was evidenced by re-endothelialization at 2 weeks and subsequent appearance of vasomotor function at 4 weeks. Pharmacological inhibition of inducible NOS (iNOS) with the specific inhibitor 1400W, administered between 2 and 4 weeks after grafting, when re-endothelialization was complete, resulted in neoadventitial inflammation, neoadventitial thickening and impaired functional remodelling. Conclusion: Completion of re-endothelialization is pivotal in vein graft remodelling in the mouse and is associated with a series of changes in inflammation, proliferation and initiation of vascular functional remodelling. After re-endothelialization, iNOS upregulation may be an important mechanism to prevent secondary neoadventitial inflammation and preserve ongoing functional remodelling. iNOS activity could therefore be beneficial for long-term patency of the vein graft.
Hypoxia in Abdominal Aortic Aneurysm Supports a Role for HIF-1α and Ets-1 as Drivers of Matrix Metalloproteinase Upregulation in Human Aortic Smooth Muscle Cells
Authors: Erdozain Olivia J. , Pegrum Susan , Winrow Vivienne R. , Horrocks Michael , Stevens Cliff R.
Published: October 2010

Background/Aims: We sought to determine whether hypoxia is an initiating factor in the matrix metalloproteinase-2 (MMP-2) up-regulation observed in abdominal aortic aneurysm (AAA) and whether hypoxia-inducible factor-1α (HIF-1α) or Ets-1 are mediating factors. Methods: Human AAA and normal aorta were analysed for MMP-2, HIF-1α and Ets-1 by immunohistochemistry. Human aortic smooth muscle cell (HASMC) cultures exposed to experimental hypoxia were analysed for hypoxia-induced proteins using gelatin zymography and immunoblotting. Multiplex PCR was used to detect MMP-1, membrane-type (MT)-MMP-1, MMP-2, MMP-3, MMP-7 and MMP-9. Results: AAA tissues expressed HIF-1α, MMP-2 and Ets-1 strongly within smooth muscle cells and inflammatory infiltrate of the tunica media. Up-regulated MMP-2 was detected in hypoxia-exposed HASMC (p < 0.05), with MMP-9 elevations after exposure to sequential O2 decreases (p < 0.05). Immunoblotting confirmed HIF-1α, Ets-1, VEGF and MMP-2 are up-regulated in HASMC exposed to hypoxia (p < 0.05), while transcription for MMP-1, MT-MMP-1, MMP-9, MMP-2 and MMP-7 (p < 0.05) increased in hypoxic HASMCs. Conclusion: Hypoxia facilitates HIF-1α, Ets-1 and VEGF up-regulation in addition to driving enhanced secretion of MMP-2 and MMP-9 by HASMC. Enhanced transcription of factors relevant to aneurysmal disease in hypoxia indicates possible roles in disease progression and potential targets for therapeutic intervention.
Reduced Precuneus Deactivation during Object Naming in Patients with Mild Cognitive Impairment, Alzheimer’s Disease, and Frontotemporal Lobar Degeneration
Authors: Frings Lars , Dressel Katharina , Abel Stefanie , Saur Dorothee , Kümmerer Dorothee , Mader Irina , Weiller Cornelius , Hüll Michael
Published: October 2010

The precuneus is part of the default network of the human brain, which exhibits a high level of activity during the resting state and lower activity during task-related behavior. Typically, the posterior midline areas show this characteristic response in functional magnetic resonance imaging (fMRI) studies. In Alzheimer’s disease (AD) and mild cognitive impairment (MCI), subjects exhibit a lack of this typical deactivation. The interpretation of these findings, however, is obfuscated by the presence of local pathology and atrophy in AD. In contrast to AD, in patients with early frontotemporal lobar degeneration (FTLD), the precuneus is virtually free of local neuropathology. In this study, we demonstrate reduced fMRI signal in the precuneus in a group of patients with FTLD during a confrontation naming task. We show that this effect in FTLD patients was (1) similar to that observed in AD and MCI and (2) not related to the degree of gray matter atrophy in the precuneus. We hypothesize that reduced deactivation of the default network is not related to local pathology but to a lack of connectivity, which decreases in both FTLD and AD, the major cortical dementias.
Effects of Estrogen on Beta-Amyloid-Induced Cholinergic Cell Death in the Nucleus Basalis Magnocellularis
Authors: Szegő Éva M. , Csorba Attila , Janáky Tamás , Kékesi Katalin A. , Ábrahám István M. , Mórotz Gábor M. , Penke Botond , Palkovits Miklós , Murvai Ünige , Kellermayer Miklós S.Z. , Kardos József , Juhász Gábor D.
Published: October 2010

Alzheimer disease is characterized by accumulation of β-amyloid (Aβ) and cognitive dysfunctions linked to early loss of cholinergic neurons. As estrogen-based hormone replacement therapy has beneficial effects on cognition of demented patients, and it may prevent memory impairments, we investigated the effect of estrogen-pretreatment on Aβ-induced cholinergic neurodegeneration in the nucleus basalis magnocellularis (NBM). We tested which Aβ species induces the more pronounced cholinotoxic effect in vivo. We injected different Aβ assemblies in the NBM of mice, and measured cholinergic cell and cortical fiber loss. Spherical Aβ oligomers had the most toxic effect. Pretreatment of ovariectomized mice with estrogen before Aβ injection decreased cholinergic neuron loss and partly prevented fiber degeneration. By using proteomics, we searched for proteins involved in estrogen-mediated protection and in Aβ toxicity 24 h following injection. The change in expression of, e.g., DJ-1, NADH ubiquinone oxidoreductase, ATP synthase, phosphatidylethanolamine-binding protein 1, protein phosphatase 2A and dimethylarginine dimethylaminohydrolase 1 support our hypothesis that Aβ induces mitochondrial dysfunction, decreases MAPK signaling, and increases NOS activation in NBM. On the other hand, altered expression of, e.g., MAP kinase kinase 1 and 2, protein phosphatase 1 and 2A by Aβ might increase MAPK suppression and NOS signaling in the cortical target area. Estrogen pretreatment reversed most of the changes in the proteome in both areas. Our experiments suggest that regulation of the MAPK pathway, mitochondrial pH and NO production may all contribute to Aβ toxicity, and their regulation can be prevented partly by estrogen pretreatment.
Effects of Legal Antibiotic Restrictions on Consumption of Broad-Spectrum Beta-Lactam Antibiotics, Glycopeptides and Amphotericin B
Authors: Kurt H. , Karabay O. , Birengel S. , Memikoglu O. , Yılmaz Bozkurt G. , Yalçı A.
Published: October 2010

In 2002, antimicrobial drugs were the most frequently prescribed drugs in Turkey. On February 15, 2003, the Turkish Government implemented a new Budget Application Instruction (BAI) to promote rational antibiotic usage in order to decrease the costs. This BAI restricted the reimbursement of certain antibiotics without prescription or approval by the infectious diseases specialists (IDS). The purpose of this study is to evaluate the effect of BAI on antibiotic consumption for the 3 years before and 2 years after its implementation, according to IMS Health Office findings. Based on the data of the IMS Health Turkey Office, the amount of some broad-spectrum antibiotics (piperacillin/tazobactam, imipenem, meropenem, cefoperazone/sulbactam, ceftazidime, cefepime, teicoplanin, vancomycin, and amphotericin B) that were prescribed by IDS between 2000 and 2002 and between 2003 and 2004 are determined. The Anatomical Therapeutic Chemical classification and the defined daily dose (DDD)/1,000 methodology are used to calculate antibiotic consumption. Total antibiotic consumption before BAI, in 2000, 2001 and 2002 was 0.091, 0.107 and 0.119 DDD/1,000 inhabitant-days, respectively, and after BAI, in 2003 and 2004, 0.137 and 0.135 DDD/1,000 inhabitant-days, respectively. Average utilization of antibiotics before the implementation of BAI was 0.105 DDD and increased to 0.136 DDD after BAI. Antibiotic consumption has increased 1.3-fold after the implementation of BAI. However, the effect of restricted antibiotic utilization was revealed especially in the second year after BAI. The consumption of antimicrobials decreased to 0.135 in 2004 while it was 0.137 in 2003.
An Analytical Model of Evaporation Efficiency for Unsaturated Soil Surfaces with an Arbitrary Thickness
Authors: Merlin Olivier , Al Bitar Ahmad , Rivalland Vincent , Béziat Pierre , Ceschia Eric , Dedieu Gérard
Published: October 2010

Analytical expressions of evaporative efficiency over bare soil (defined as the ratio of actual to potential soil evaporation) have been limited to soil layers with a fixed depth and/or to specific atmospheric conditions. To fill the gap, a new analytical model is developed for arbitrary soil thicknesses and varying boundary layer conditions. The soil evaporative efficiency is written [0.5 − 0.5 cos(πθL/θmax)]P with θL being the water content in the soil layer of thickness L, θmax being the soil moisture at saturation, and P being a function of L and potential soil evaporation. This formulation predicts soil evaporative efficiency in both energy-driven and moisture-driven conditions, which correspond to P < 0.5 and P > 0.5, respectively. For P = 0.5, an equilibrium state is identified when retention forces in the soil compensate the evaporative demand above the soil surface. The approach is applied to in situ measurements of actual evaporation, potential evaporation, and soil moisture at five different depths (5, 10, 30, 60, and 100 cm) collected in summer at two sites in southwestern France. It is found that (i) soil evaporative efficiency cannot be considered as a function of soil moisture only because it also depends on potential evaporation, (ii) retention forces in the soil increase in reaction to an increase of potential evaporation, and (iii) the model is able to accurately predict the soil evaporation process for soil layers with an arbitrary thickness up to 100 cm. This new model representation is expected to facilitate the coupling of land surface models with multisensor (multisensing depth) remote sensing data.
Development and Testing of Polar WRF. Part III: Arctic Land*
Authors: Hines Keith M. , Bromwich David H. , Bai Le-Sheng , Barlage Michael , Slater Andrew G.
Published: October 2010

A version of the state-of-the-art Weather Research and Forecasting model (WRF) has been developed for use in polar climates. The model known as “Polar WRF” is tested for land areas with a western Arctic grid that has 25-km resolution. This work serves as preparation for the high-resolution Arctic System Reanalysis of the years 2000–10. The model is based upon WRF version 3.0.1.1, with improvements to the Noah land surface model and snow/ice treatment. Simulations consist of a series of 48-h integrations initialized daily at 0000 UTC, with the initial 24 h taken as spinup for atmospheric hydrology and boundary layer processes. Soil temperature and moisture that have a much slower spinup than the atmosphere are cycled from 48-h output of earlier runs. Arctic conditions are simulated for a winter-to-summer seasonal cycle from 15 November 2006 to 1 August 2007. Simulation results are compared with a variety of observations from several Alaskan sites, with emphasis on the North Slope. Polar WRF simulation results show good agreement with most near-surface observations. Warm temperature biases are found for winter and summer. A sensitivity experiment with reduced soil heat conductivity, however, improves simulation of near-surface temperature, ground heat flux, and soil temperature during winter. There is a marked deficit in summer cloud cover over land with excessive incident shortwave radiation. The cloud deficit may result from anomalous vertical mixing of moisture by the turbulence parameterization. The new snow albedo parameterization for WRF 3.1.1 is successfully tested for snowmelt over the North Slope of Alaska.
Comparison of Modeled and Observed Accumulated Convective Precipitation in Mountainous and Flat Land Areas
Authors: Ćurić Mladjen , Janc Dejan
Published: October 2010

Convective precipitation is the main cause of extreme rainfall events in small areas. Its primary characteristics are both large spatial and temporal variability. For this reason, the monitoring of accumulated precipitation fields (liquid and solid components) at the surface is difficult to carry out through the use of rain gauge networks or remote sensing observations. Alternatively, numerical models may be a useful tool to simulate convective precipitation for various analyses and predictions. This paper focuses on improving quantitative convective precipitation estimates that are obtained with a cloud-resolving model. This aim is attained by using the appropriate cloud drop size distribution and modified single sounding data. The authors perform comparisons between observations and three model samples of the areal-accumulated convective precipitation for a 15-yr period over mountainous and flat land areas with 45 and 29 convective events, respectively. They compare the results from a numerical cloud model that uses 2 different microphysical schemes—the unified Khrgian–Mazin size distribution of cloud drops—and an alternative scheme that is a combination of a monodispersed cloud droplet spectrum and the Marshall–Palmer size distribution for raindrops. The authors’ statistical analysis shows that the model version with the Khrgian–Mazin size distribution and the new initial conditions better simulates the observed areal-accumulated convective precipitation than the alternative microphysical approach for both study areas. The model simulations with the Khrgian–Mazin size distribution most closely match observations for the flat land area with a correlation coefficient of 0.94, while it is somewhat lower (0.89) for the mountainous area. Use of the alternative microphysical approach, on the other hand, underestimates the observed precipitation, and has the lowest correlation coefficient among the methods, 0.82 for the mountainous area and 0.85 for the flat land.
Effects of Surface Heat and Moisture Exchange on ARW-WRF Warm-Season Precipitation Forecasts over the Central United States
Authors: Trier S. B. , LeMone M. A. , Chen F. , Manning K. W.
Published: October 2010

The evolution of the daytime planetary boundary layer (PBL) and its association with warm-season precipitation is strongly impacted by land–atmosphere heat and moisture exchange (hereafter surface exchange). However, substantial uncertainty exists in the parameterization of the surface exchange in numerical weather prediction (NWP) models. In the current study, the authors examine 0–24-h convection-permitting forecasts with different surface exchange strengths for a 6-day period during the International H2O Project (IHOP_2002). Results indicate sensitivity in the timing of simulated afternoon convection initiation and subsequent precipitation amounts to variations in surface exchange strength. Convection initiation in simulations with weak surface exchange was delayed by 2–3 h compared to simulations with strong surface exchange, and area-averaged total precipitation amounts were less by up to a factor of 2. Over the western high plains (105°–100°W longitude), where deep convection is locally generated, simulations using a formulation for surface exchange that varied with the vegetation category (height) produced area-averaged diurnal cycles of forecasted precipitation amounts in better agreement with observations than simulations that used the current Advanced Research Weather Research and Forecasting Model (ARW-WRF) formulation. Parcel theory is used to diagnose mechanisms by which differences in surface exchange influence convection initiation in individual case studies. The more rapid initiation in simulations with strong surface exchange results from a more rapid removal of negative buoyancy beneath the level of free convection, which arises primarily from greater PBL warming.
Political and Policy Barriers to Basic Skills Education in the California Community Colleges
Authors: Offenstein Jeremy , Shulock Nancy
Published: October 2010

California’s only open access intuitions, the community colleges, are particularly affected by the difficult challenge of educating students academically unprepared for college. To address this challenge, the community colleges launched the Basic Skills Initiative in 2006. This initiative seeks to improve basic skills education by learning about effective practices and increasing their use across the 112 colleges through professional development and increased funding. Despite its strengths, the potential success of the initiative is limited by state and system policies that are not well aligned with the goals of the initiative. Greater success could be had through reforming state and system policy.
Enamel-Smear Compromises Bonding by Mild Self-Etch Adhesives
Authors: Mine A. , De Munck J. , Cardoso M. Vivan , Van Landuyt K.L. , Poitevin A. , Kuboki T. , Yoshida Y. , Suzuki K. , Van Meerbeek B.
Published: October 2010

In light of the increased popularity of less acidic, so-called ‘ultra-mild’ self-etch adhesives, adhesion to enamel is becoming more critical. It is hypothesized that this compromised enamel bonding should, to a certain extent, be attributed to interference of bur debris smeared across enamel during cavity preparation. High-resolution transmission electron microscopy revealed that the enamel smear layer differed not only in thickness, but also in crystal density and size, depending on the surface-preparation method used. Lab-demineralization of sections clearly disclosed that resin-infiltration of an ultra-mild self-etch adhesive progressed preferentially along micro-cracks that were abundantly present at and underneath the bur-cut enamel surface. The surface-preparation method significantly affected the nature of the smear layer and the interaction with the ultra-mild adhesive, being more uniform and dense for a lab-SiC-prepared surface vs. a clinically relevant bur-prepared surface.
Medical Sociology and Health Services Research: Past Accomplishments and Future Policy Challenges
Authors: Wright Eric R. , Perry Brea L.
Published: October 2010

The rising costs and inconsistent quality of health care in the United States have raised significant questions among professionals, policy makers, and the public about the way health services are being delivered. For the past 50 years, medical sociologists have made significant contributions in improving our understanding of the nature and impact of the organizations that constitute our health care system. In this article, we discuss three central findings in the sociology of health services: (1) health services in the U.S. are unequally distributed, contributing to health inequalities across status groups; (2) social institutions reproduce health care inequalities by constraining and enabling the actions of health service organizations, health care providers, and consumers; and (3) the structure and dynamics of health care organizations shape the quality, effectiveness, and outcomes of health services for different groups and communities. We conclude with a discussion of the policy implications of these findings for future health care reform efforts.
Bioethics, Raw and Cooked: Extraordinary Conflict and Everyday Practice
Authors: Bosk Charles L.
Published: October 2010

This article explains the emergence, growth, and institutional anchoring of bioethics in both policy and clinical arenas. Under the heading of principlism, bioethics developed a public language for resolving disputes that allowed it to transform disputes involving sacred matters into profane work routines. At the same time, having principlism as a common language for solving practical disputes allowed “ethics work” in health care to be separated from moral theorizing as a practical activity. Two issues—the right to die and the protection of research subjects—serve to illustrate the process through which bioethics established a large institutional footprint in health care.
Simulation of simultaneous unbalances in power system transient stability analysis
Authors: Koochaki Amangaldi , Kouhsari Shahram Montaser
Published: October 2010

In this paper a novel method based on network decomposition algorithm is presented to implement simultaneous unbalances in power system transient stability (T/S) studies. The proposed network decomposition algorithm employs bus-tearing and Diakoptics concepts. In combination with Large Change Sensitivity (LCS) analysis, which allows the procedure to evaluate system responses without resolving the whole problem, an accurate method is developed to solve the simultaneous unbalances in T/S analysis. The proposed method is implemented successfully in software and the results are validated in comparison with time domain simulations. The performance of our proposed method is investigated in this paper for a 14-bus IEEE test system. The results reveal the credibility of the method.
Continuities, Scope, and Limitations of the Argentine Piquetero Movement
Authors: Benclowicz José Daniel
Published: October 2010

Study of the unemployed workers’ movement in Tartagal and Mosconi, Argentina, shows significant continuities between the piquetero organizations there and the militant unions of the past. In the new context characterized by massive unemployment, leaders who had left-wing union or political experience led and developed protest movements that can be framed in terms of capital-labor conflict. Grassroots activists without previous experience in organizing collective action learned from their participation in the struggle.
Community participation in the cultural adaptation of a prevention curriculum
Authors: Clinton Amanda , Amesty Elvia
Published: October 2010

The present project analysed the use of participatory models during the process of application of a prevention program with preschool-aged children in Maracaibo, Venezuela. Relevant phases in achieving community collaboration are delineated and challenges are discussed. Results indicate that participatory models provided an effective means of introducing and carrying out a prevention program in local schools although a significant level of commitment was required from all groups involved.
School psychologists and the secret illness: Perceived knowledge, role preferences, and training needs regarding the prevention and treatment of internalizing disorders
Authors: Miller David N. , Jome LaRae M.
Published: October 2010

This descriptive study examined the perceptions of a national sample of school psychologists in the United States regarding their perceived knowledge, preferred roles, and training needs in the prevention and treatment of nine prominent child and adolescent internalizing disorders. The results indicated that participants perceived the prevention of all nine internalizing disorders to be an appropriate role for school psychologists, and that they perceived the school-based treatment of particular disorders, such as school phobia/refusal, to be an appropriate role as well. A majority of the sample reported the need for some or significant additional training in all nine internalizing disorders. Limitations of the study and needs for future research are discussed.
Teaching Applied Behavior Analysis Knowledge Competencies to Direct-Care Service Providers: Outcome Assessment and Social Validation of a Training Program
Authors: Luiselli James K. , Bass Jennifer D. , Whitcomb Sara A.
Published: October 2010

Staff training is a critical performance improvement objective within behavioral health care organizations. This study evaluated a systematic training program for teaching applied behavior analysis knowledge competencies to newly hired direct-care employees at a day and residential habilitation services agency for adults with intellectual and developmental disabilities. Three content areas—measurement, behavior support, and skill acquisition—were trained in a group format using Powerpoint® presentations that featured didactic instruction, practice exercises, and video demonstrations. The employees completed an assessment of knowledge test before and after training in each content area. Across five training groups, the average correct posttraining test scores were consistently higher than pretraining test scores. A social validity assessment revealed that the employees judged the training program favorably along several dimensions. Issues pertaining to staff training and performance improvement initiatives are discussed.
A Graphical Approach to Evaluating Equating Using Test Characteristic Curves
Authors: Wyse Adam E. , Reckase Mark D.
Published: October 2010

An essential concern in the application of any equating procedure is determining whether tests can be considered equated after the tests have been placed onto a common scale. This article clarifies one equating criterion, the first-order equity property of equating, and develops a new method for evaluating equating that is linked to this criterion. The new approach involves graphically examining the difference in test characteristic curves (TCCs), calculating the maximum absolute difference between the TCCs, and comparing the differences in TCCs to the difference that matters (DTM). The new approach is applied to evaluate the equating of the Multistate Bar Exam (MBE) for six different item response theory (IRT) scaling approaches in the common item nonequivalent groups design. The new approach is also contrasted with Tong and Kolen’s (2005) index for assessing first-order equity. The empirical investigations indicated that the Stocking-Lord and fixed-parameter equating methods appear to perform the best for equating the MBE and that the use of concurrent calibration is not desirable.
Collective Turnover at the Group, Unit, and Organizational Levels: Evidence, Issues, and Implications
Authors: Hausknecht John P. , Trevor Charlie O.
Published: October 2010

Studies of the causes and consequences of turnover at the group, unit, or organizational level of analysis have proliferated in recent years. Indicative of its importance, turnover rate research spans numerous academic disciplines and their respective journals. This broad interest is fueled by the considerable implications of turnover rates predicting broader measures of organizational effectiveness (productivity, customer outcomes, firm performance) as well as by the related perspective that collective turnover is an important outcome in its own right. The goal of this review is to critically examine and extract meaningful insights from research on the causes and consequences of group, unit, and organizational turnover. The review is organized around five major “considerations,” including (1) measurement and levels of analysis issues, (2) consequences, (3) curvilinear and interaction effects, (4) methodological and conceptual issues, and (5) antecedents. The review concludes with broad directions for future research.
Spermatocytic Seminoma With Neuroectodermal Differentiation and Sertoli Cell Tumor in a Dog
Authors: Saegusa Y. , Hayashi H. , Taniai E. , Imaoka M. , Ohishi T. , Wang L. , Mitsumori K. , Shibutani M.
Published: October 2010

Two distinct nodules developed in a cryptorchid testis of an 8-year-old male West Highland White Terrier. One nodule was a Sertoli cell tumor. The other was a spermatocytic seminoma with focal primitive neuroectodermal differentiation: formation of Homer–Wright rosettes and perivascular pseudorosettes, with immunoreactivity for S-100 protein, neuron-specific enolase, synaptophysin, neurofilament–68 kDa, microtubule-associated protein 2, and vimentin. The dog was alive and healthy 2 years after castration.
Professional Learning for Teachers Without Special Education Qualifications Working With Students With Severe Disabilities
Authors: Stephenson Jennifer , Carter Mark , Arthur-Kelly Michael
Published: October 2010

In this article, the authors report on an individualized professional learning activity, based on the principles described by Gersten and colleagues, implemented by two academics with three teachers without special education qualifications teaching students with severe and multiple disabilities. The professional learning consisted of consultation based around observation of classroom practice (live or by video recording) focusing on the use of strategies to increase the number of opportunities for communication offered to students. Analysis of video recordings of targeted activities over baseline and intervention sessions demonstrated an increase in the opportunities teachers offered, with larger effects in two of the classes.
An Examination of the Predictive Validity of the Risk Matrix 2000 in England and Wales
Authors: Barnett Georgia D. , Wakeling Helen C. , Howard Philip D.
Published: October 2010

This study examined the predictive validity of an actuarial risk-assessment tool with convicted sexual offenders in England and Wales. A modified version of the RM2000/s scale and the RM2000 v and c scales (Thornton et al., 2003) were examined for accuracy in predicting proven sexual violent, nonsexual violent, and combined sexual and/or nonsexual violent reoffending in a sample of sexual offenders who had either started a community sentence or been released from prison into the community by March 2007. Rates of proven reoffending were examined at 2 years for the majority of the sample ( n = 4,946), and 4 years ( n = 578) for those for whom these data were available. The predictive validity of the RM2000 scales was also explored for different subgroups of sexual offenders to assess the robustness of the tool. Both the modified RM2000/s and the complete v and c scales effectively classified offenders into distinct risk categories that differed significantly in rates of proven sexual and/or nonsexual violent reoffending. Survival analyses on the RM2000/s and v scales ( N = 9,284) indicated that the higher risk groups offended more quickly and at a higher rate than lower risk groups. The relative predictive validity of the RM2000/s, v, and c, as calculated using Receiver Operating Characteristics (ROC) analyses, were moderate (.68) for RM2000/s and large for both the RM2000/c (.73) and RM2000/v (.80), at the 2-year follow-up. RM2000/s was moderately accurate in predicting relative risk of proven sexual reoffending for a variety of subgroups of sexual offenders.
Young adults’ images of abstaining and drinking: Prototype dimensions, correlates and assessment methods
Authors: Zimmermann Friederike , Sieverding Monika
Published: October 2010

This research investigated contents of actor and abstainer prototypes with regard to young adults’ social drinking combining quantitative and qualitative approaches (adjective ratings, N = 300; open answers, N = 90). Exploratory and confirmatory factor analyses yielded two factors (sociability/hedonism, responsibility) in both prototypes, confirmed by qualitative data. Given the importance for intention and willingness to drink alcohol, interventions should focus on the factor ‘sociability/hedonism’ of the actor and the abstainer prototype to reduce heavy drinking; addressing ‘responsibility’ may be ineffective. Participants’ evaluations appeared to be less prone to mean tendencies subsequent to open answers compared with adjective scales.
The Missing Men: High Risk of Disease in Men of Mexican Origin
Authors: Salinas Jennifer , McCormick Joseph B. , Rentfro Anne , Hanis Craig , Md Monir Hossain  , Fisher-Hoch Susan P.
Published: October 2010

The present study sought to determine gender- and age-specific prevalences of chronic diseases in an urban Mexican American border community. The Cameron County Hispanic Cohort (CCHC; n = 2,000) was selected using a multistaged cluster design. Sociodemographics, anthropometric measures, and blood samples were collected on each participant. More women were obese (55.1%) than men (44.8%). Men had significantly higher rates of diabetes (20.4% for men vs. 15.8% for women, p < .05) and undiagnosed diabetes (6.2% for men vs. 2.4% for women, p < .01); the prevalence of diabetes rose steeply between the ages of 40 and 49 years. Men were significantly more likely to have serum cholesterol levels of 200 mg/dL and elevated low-density lipoprotein levels (22.6% vs. 26.1%, p < .01). Mexican American males in the U.S./Mexico border region have a high prevalence of obesity in younger men and higher overall rates of diabetes, including undiagnosed diabetes, and significantly higher serum cholesterol levels than women.
Early Adversity and Developmental Outcomes
Authors: Champagne Frances A.
Published: October 2010

Longitudinal studies in humans demonstrate the association between prenatal and postnatal experiences of adversity and long-term changes in neurodevelopment. These studies raise the question of how experiences become incorporated at a biological level to induce persistent changes in functioning. Laboratory studies using animal models and recent analyses in human cohorts implicate epigenetic mechanisms as a possible route through which these environmental effects are achieved. In particular, there is evidence that changes in DNA methylation are associated with early life experiences with consequences for gene expression and behavior. Despite the potential stability of DNA methylation, it is apparent that this epigenetic mark can be dynamically modified through pharmacological targeting and behavioral experiences. Developmental plasticity may also be achieved through modification of the juvenile environment. Although these juvenile experiences may lead to common endpoints, there is evidence suggesting that the effects of early and later life experiences may be achieved by different molecular pathways. This review discusses evidence for the role of epigenetic mechanisms in shaping developmental trajectories in response to early life experience as well as the potential plasticity that can occur beyond the perinatal period. These studies have implications for approaches to intervention and suggest the importance of considering individual differences in genetic and epigenetic vulnerability in developing treatment strategies.
Understanding the Early Origins of the Education–Health Gradient
Authors: Conti Gabriella , Heckman James J.
Published: October 2010

In this article, we develop a framework for analyzing the causal effects of interventions in the presence of latent factors that could affect outcomes, even in the absence of interventions. This framework will be useful in situations in which genes are included among the latent factors. We estimate the model and study the early origins of observed later-life disparities by education. We determine the role played by cognitive, noncognitive, and early health endowments. We identify the causal effect of education on health and health-related behaviors. We show that family background characteristics and cognitive, noncognitive, and health endowments developed by age 10 are important determinants of health disparities at age 30. We also show that not properly accounting for personality traits results in overestimation of the importance of cognitive ability in determining later health. Selection on preexisting traits explains more than half of the observed differences in poor health and obesity. Education has an important causal effect in explaining differences in smoking rates. There are significant gender differences. We go beyond the current literature, which typically estimates mean effects, to compute distributions of treatment effects. We show that the effect of education on health varies among individuals who are similar in their observed characteristics, and how a mean effect can hide gains and losses for different individuals. This analysis highlights the crucial role played by promotion of good health at an early age and the importance of prevention in the reduction of health disparities. We speculate about how the model can be applied to genetic studies.
Mendelian Randomization for Strengthening Causal Inference in Observational Studies
Authors: Smith George Davey
Published: October 2010

Identification of environmentally modifiable factors causally influencing disease risk is fundamental to public-health improvement strategies. Unfortunately, observational epidemiological studies are limited in their ability to reliably identify such causal associations, reflected in the many cases in which conventional epidemiological studies have apparently identified such associations that randomized controlled trials have failed to verify. The use of genetic variants as proxy measures of exposure —an application of the Mendelian randomization principle—can contribute to strengthening causal inference. Genetic variants are not subject to bias due to reverse causation (disease processes influencing exposure, rather than vice versa) or recall bias, and if simple precautions are applied, they are not influenced by confounding or attenuation by errors. The principles of Mendelian randomization are illustrated with specific reference to studies of the effects of alcohol intake on various health-related outcomes through the utilization of genetic variants related to alcohol metabolism (in ALDH2 and ADH1B). Ways of incorporating Gene × Environment interactions into the Mendelian randomization framework are developed, and the strengths and limitations of the approach discussed.
Refining Intervention Targets in Family-Based Research
Authors: Leve Leslie D. , Harold Gordon T. , Ge Xiaojia , Neiderhiser Jenae M. , Patterson Gerald
Published: October 2010

The results from a large body of family-based research studies indicate that modifying the environment (specifically dimensions of the social environment) through intervention is an effective mechanism for achieving positive outcomes. Parallel to this work is a growing body of evidence from genetically informed studies indicating that social environmental factors are central to enhancing or offsetting genetic influences. Increased precision in the understanding of the role of the social environment in offsetting genetic risk might provide new information about environmental mechanisms that could be applied to prevention science. However, at present, the multifaceted conceptualization of the environment in prevention science is mismatched with the more limited measurement of the environment in many genetically informed studies. In this article, we present a framework for translating quantitative behavioral genetic research to inform the development of preventive interventions. The measurement of environmental indices amenable to modification is discussed within the context of quantitative behavioral genetic studies. In particular, emphasis is placed on the necessary elements that lead to benefits in prevention science, specifically the development of evidence-based interventions. We provide an example from an ongoing prospective adoption study to illustrate the potential of this translational process to inform the selection of preventive intervention targets.
Contemporary Modeling of Gene × Environment Effects in Randomized Multivariate Longitudinal Studies
Authors: McArdle John J. , Prescott Carol A.
Published: October 2010

There is a great deal of interest in the analysis of Genotype × Environment interactions (G×E). There are some limitations in the typical models for the analysis of G×E, including well-known statistical problems in identifying interactions and unobserved heterogeneity of persons across groups. The impact of a treatment may depend on the level of an unobserved variable, and this variation may dampen the estimated impact of treatment. Some researchers have noted that genetic variation may sometimes account for unobserved, and hence unaccounted for, heterogeneity. The statistical power associated with the G×E design has been studied in many different ways, and most results show that the small effects expected require relatively large or nonrepresentative samples (i.e., extreme groups). In this article, we describe some alternative approaches, such as randomized designs with multiple measures, multiple groups, multiple occasions, and analyses, to identify latent (unobserved) classes of people. These approaches are illustrated with data from the Aging, Demographics, and Memory Study (part of the Health and Retirement Study) examining the relations among episodic memory (based on word recall), APOE4 genotype, and educational attainment (as a proxy for an environmental exposure). Randomized clinical trials (RCTs) and randomized field trials (RFTs) have multiple strengths in the estimation of causal influences, and we discuss how measured genotypes can be incorporated into these designs. Use of these contemporary modeling techniques often requires different kinds of data be collected and encourages the formation of parsimonious models with fewer overall parameters, allowing specific G×E hypotheses to be investigated with a reasonable statistical foundation.
Causal Inference and Observational Research
Authors: McGue Matt , Osler Merete , Christensen Kaare
Published: October 2010

Valid causal inference is central to progress in theoretical and applied psychology. Although the randomized experiment is widely considered the gold standard for determining whether a given exposure increases the likelihood of some specified outcome, experiments are not always feasible and in some cases can result in biased estimates of causal effects. Alternatively, standard observational approaches are limited by the possibility of confounding, reverse causation, and the nonrandom distribution of exposure (i.e., selection). We describe the counterfactual model of causation and apply it to the challenges of causal inference in observational research, with a particular focus on aging. We argue that the study of twin pairs discordant on exposure, and in particular discordant monozygotic twins, provides a useful analog to the idealized counterfactual design. A review of discordant-twin studies in aging reveals that they are consistent with, but do not unambiguously establish, a causal effect of lifestyle factors on important late-life outcomes. Nonetheless, the existing studies are few in number and have clear limitations that have not always been considered in interpreting their results. It is concluded that twin researchers could make greater use of the discordant-twin design as one approach to strengthen causal inferences in observational research.