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Showing papers by "Virginia Commonwealth University published in 2005"



Journal ArticleDOI
TL;DR: In this paper, the structural and point defects caused by lattice and stacking mismatch with substrates are discussed. But even the best of the three binaries, InN, AIN and AIN as well as their ternary compounds, contain many structural defects, and these defects notably affect the electrical and optical properties of the host material.
Abstract: Gallium nitride (GaN) and its allied binaries InN and AIN as well as their ternary compounds have gained an unprecedented attention due to their wide-ranging applications encompassing green, blue, violet, and ultraviolet (UV) emitters and detectors (in photon ranges inaccessible by other semiconductors) and high-power amplifiers. However, even the best of the three binaries, GaN, contains many structural and point defects caused to a large extent by lattice and stacking mismatch with substrates. These defects notably affect the electrical and optical properties of the host material and can seriously degrade the performance and reliability of devices made based on these nitride semiconductors. Even though GaN broke the long-standing paradigm that high density of dislocations precludes acceptable device performance, point defects have taken the center stage as they exacerbate efforts to increase the efficiency of emitters, increase laser operation lifetime, and lead to anomalies in electronic devices. The p...

1,724 citations


Journal ArticleDOI
TL;DR: Gene transfer between staphylococci and low-GC-content gram-positive bacteria appears to have shaped their virulence and resistance profiles, and overall differences in pathogenicity can be attributed to genome islands in S. aureus and S. epidermidis.
Abstract: Staphylococcus aureus is an opportunistic pathogen and the major causative agent of numerous hospital- and community-acquired infections. Staphylococcus epidermidis has emerged as a causative agent of infections often associated with implanted medical devices. We have sequenced the ∼2.8-Mb genome of S. aureus COL, an early methicillin-resistant isolate, and the ∼2.6-Mb genome of S. epidermidis RP62a, a methicillin-resistant biofilm isolate. Comparative analysis of these and other staphylococcal genomes was used to explore the evolution of virulence and resistance between these two species. The S. aureus and S. epidermidis genomes are syntenic throughout their lengths and share a core set of 1,681 open reading frames. Genome islands in nonsyntenic regions are the primary source of variations in pathogenicity and resistance. Gene transfer between staphylococci and low-GC-content gram-positive bacteria appears to have shaped their virulence and resistance profiles. Integrated plasmids in S. epidermidis carry genes encoding resistance to cadmium and species-specific LPXTG surface proteins. A novel genome island encodes multiple phenol-soluble modulins, a potential S. epidermidis virulence factor. S. epidermidis contains the cap operon, encoding the polyglutamate capsule, a major virulence factor in Bacillus anthracis. Additional phenotypic differences are likely the result of single nucleotide polymorphisms, which are most numerous in cell envelope proteins. Overall differences in pathogenicity can be attributed to genome islands in S. aureus which encode enterotoxins, exotoxins, leukocidins, and leukotoxins not found in S. epidermidis.

1,075 citations


Journal ArticleDOI
25 Apr 2005-Polymer
TL;DR: In this paper, a semi-empirical analysis of the transition from electrospraying to electrospinning in the good solvent, non-specific polymer-polymer interaction limit is presented.

1,058 citations


Journal ArticleDOI
TL;DR: The origins of the concept of race are reviewed, placing the contemporary discussion of racial differences in an anthropological and historical context.
Abstract: Racialized science seeks to explain human population differences in health, intelligence, education, and wealth as the consequence of immutable, biologically based differences between "racial" groups. Recent advances in the sequencing of the human genome and in an understanding of biological correlates of behavior have fueled racialized science, despite evidence that racial groups are not genetically discrete, reliably measured, or scientifically meaningful. Yet even these counterarguments often fail to take into account the origin and history of the idea of race. This article reviews the origins of the concept of race, placing the contemporary discussion of racial differences in an anthropological and historical context.

953 citations


Journal ArticleDOI
TL;DR: The authors combine relevant findings in behavioral genetics with their own analysis of data on a large sample of twins to test the hypothesis that, contrary to the assumptions embedded in political science research, political attitudes have genetic as well as environmental causes.
Abstract: Why do people think and act politically in the manner they do? Despite the foundational nature of this question, answers are unfortunately incomplete and unnecessarily tentative, largely because political scientists do not take seriously the possibility of nonenvironmental influences. The suggestion that people could be born with political predispositions strikes many as far-fetched, odd, even perverse. However, researchers in other disciplines—‐ notably behavioral genetics—‐have uncovered a substantial heritable component for many social attitudes and behaviors and it seems unlikely that political attitudes and behaviors are completely immune from such forces. In this article, we combine relevant findings in behavioral genetics with our own analysis of data on a large sample of twins to test the hypothesis that, contrary to the assumptions embedded in political science research, political attitudes have genetic as well as environmental causes. 1

845 citations


Journal ArticleDOI
TL;DR: It is shown that S1P signaling is critical for neural and vascular development and joins a growing list of signaling molecules, such as vascular endothelial growth factor, which regulate the functionally intertwined pathways of angiogenesis and neurogenesis.
Abstract: Sphingosine-1-phosphate (S1P), an important sphingolipid metabolite, regulates diverse cellular processes, including cell survival, growth, and differentiation. Here we show that S1P signaling is critical for neural and vascular development. Sphingosine kinase-null mice exhibited a deficiency of S1P which severely disturbed neurogenesis, including neural tube closure, and angiogenesis and caused embryonic lethality. A dramatic increase in apoptosis and a decrease in mitosis were seen in the developing nervous system. S1P1 receptor-null mice also showed severe defects in neurogenesis, indicating that the mechanism by which S1P promotes neurogenesis is, in part, signaling from the S1P1 receptor. Thus, S1P joins a growing list of signaling molecules, such as vascular endothelial growth factor, which regulate the functionally intertwined pathways of angiogenesis and neurogenesis. Our findings also suggest that exploitation of this potent neuronal survival pathway could lead to the development of novel therapeutic approaches for neurological diseases.

716 citations


Journal ArticleDOI
TL;DR: Treatment of pregnant women with CMV-specific hyperimmune globulin is safe, and the findings of this nonrandomized study suggest that it may be effective in the treatment and prevention of congenital CMV infection.
Abstract: methods We studied pregnant women with a primary CMV infection. The therapy group comprised women whose amniotic fluid contained either CMV or CMV DNA and who were offered intravenous CMV hyperimmune globulin at a dose of 200 U per kilogram of maternal weight. A prevention group, consisting of women with a recent primary infection before 21 weeks’ gestation or who declined amniocentesis, was offered monthly hyperimmune globulin (100 U per kilogram intravenously). results In the therapy group, 31 women received hyperimmune globulin, only 1 (3 percent) of whom gave birth to an infant with CMV disease (symptomatic at birth and handicapped at two or more years of age), as compared with 7 of 14 women who did not receive hyperimmune globulin (50 percent). Thus, hyperimmune globulin therapy was associated with a significantly lower risk of congenital CMV disease (adjusted odds ratio, 0.02; 95 percent confidence interval, i ∞ to 0.15; P<0.001). In the prevention group, 37 women received hyperimmune globulin, 6 (16 percent) of whom had infants with congenital CMV infection, as compared with 19 of 47 women (40 percent) who did not receive hyperimmune globulin. Thus, hyperimmune globulin therapy was associated with a significantly lower risk of congenital CMV infection (adjusted odds ratio, 0.32; 95 percent confidence interval, 0.10 to 0.94; P=0.04). Hyperimmune globulin therapy significantly (P<0.001) increased CMV-specific IgG concentrations and avidity and decreased natural killer cells and HLA-DR+ cells and had no adverse effects. conclusions Treatment of pregnant women with CMV-specific hyperimmune globulin is safe, and the findings of this nonrandomized study suggest that it may be effective in the treatment and prevention of congenital CMV infection. A controlled trial of this agent may now be appropriate.

674 citations


Journal ArticleDOI
TL;DR: Using first-principles calculations based on density functional theory, it is shown that Ti atoms would prefer to cluster on the C60 surface, which can significantly alter the nature of hydrogen bonding, thus affecting not only the amount of stored hydrogen but also their thermodynamics and kinetics.
Abstract: Recent efforts in finding materials suitable for storing hydrogen with large gravimetric density have focused attention on carbon-based nanostructures. Unfortunately, pure carbon nanotubes and fullerenes are unsuitable as hydrogen storage materials because of the weak bonding of the hydrogen molecules to the carbon frame. It has been shown very recently that coating of carbon nanostructures with isolated transition metal atoms such as Sc and Ti can increase the binding energy of hydrogen and lead to high storage capacity (up to 8 wt % hydrogen, which is 1.6 times the U.S. Department of Energy target set for 2005). This prediction has led to a great deal of excitement in the fuel cell community [see The Fuel Cell Review, http://fcr.iop.org/articles/features/2/7/4]. However, this prediction depends on the assumption that the metal atoms coated on the fullerene surface will remain isolated. Using first-principles calculations based on density functional theory, we show that Ti atoms would prefer to cluster on the C60 surface, which can significantly alter the nature of hydrogen bonding, thus affecting not only the amount of stored hydrogen but also their thermodynamics and kinetics.

638 citations


Journal ArticleDOI
TL;DR: In this article, a review of the recent progress in the theoretical and experimental studies of ZnO-and GaN-based DMSs is presented, focusing on the structural, optical, and magnetic properties of these materials.
Abstract: The observation of ferromagnetism in magnetic ion doped II–VI diluted magnetic semiconductors (DMSs) and oxides, and later in (Ga,Mn)As materials has inspired a great deal of research interest in a field dubbed “spintronics” of late, which could pave the way to exploit spin in addition to charge in semiconductor devices. The main challenge for practical application of the DMS materials is the attainment of a Curie temperature at or preferably above room temperature to be compatible with junction temperatures. Among the studies of transition-metal doped conventional III–V and II–VI semiconductors, transition-metal-doped ZnO and GaN became the most extensively studied topical materials since the prediction by Dietl et al., based on mean field theory, as promising candidates to realize a diluted magnetic material with Curie temperature above room temperature. The underlying assumptions, however, such as transition metal concentrations in excess of 5% and hole concentrations of about 1020 cm−3, have not gotten as much attention. The particular predictions are predicated on the assumption that hole mediated exchange interaction is responsible for magnetic ordering. Among the additional advantages of ZnO-and GaN-based DMSs are that they can be readily incorporated in the existing semiconductor heterostructure systems, where a number of optical and electronic devices have been realized, thus allowing the exploration of the underlying physics and applications based on previously unavailable combinations of quantum structures and magnetism in semiconductors. This review focuses primarily on the recent progress in the theoretical and experimental studies of ZnO- and GaN-based DMSs. One of the desirable outcomes is to obtain carrier mediated magnetism, so that the magnetic properties can be manipulated by charge control, for example through external electrical voltage. We shall first describe the basic theories forwarded for the mechanisms producing ferromagnetic behavior in DMS materials, and then review the theoretical results dealing with ZnO and GaN. The rest of the review is devoted to the structural, optical, and magnetic properties of ZnO- and GaN-based DMS materials reported in the literature. A critical review of the question concerning the origin of ferromagnetism in diluted magnetic semiconductors is given. In a similar vein, limitations and problems for identifying novel ferromagnetic DMS are briefly discussed, followed by challenges and a few examples of potential devices.

616 citations


Journal ArticleDOI
TL;DR: A difference between moral distress intensity and frequency and the importance of the environment tomoral distress intensity is revealed.
Abstract: This study examined the relationship between moral distress intensity, moral distress frequency and the ethical work environment, and explored the relationship of demographic characteristics to moral distress intensity and frequency. A group of 106 nurses from two large medical centers reported moderate levels of moral distress intensity, low levels of moral distress frequency, and a moderately positive ethical work environment. Moral distress intensity and ethical work environment were correlated with moral distress frequency. Age was negatively correlated with moral distress intensity, whereas being African American was related to higher levels of moral distress intensity. The ethical work environment predicted moral distress intensity. These results reveal a difference between moral distress intensity and frequency and the importance of the environment to moral distress intensity.

Journal ArticleDOI
TL;DR: The results demonstrate that SphK1 and SphK2 have opposing roles in the regulation of ceramide biosynthesis and suggest that the location of sphingosine 1-phosphate production dictates its functions.

Journal ArticleDOI
TL;DR: In this article, the authors use stakeholder theory to explain differences in social disclosure among countries, arguing that the manner in which the role of a corporation and its stakeholders is defined in a society will affect the extent and quality of corporate social disclosure in annual reports.

Journal ArticleDOI
TL;DR: It is concluded that the LFP brain injury model is an appropriate tool to study the cellular and mechanistic aspects of human TBI that cannot be addressed in the clinical setting, as well as for the development and characterization of novel therapeutic interventions.
Abstract: This article comprehensively reviews the lateral fluid percussion (LFP) model of traumatic brain injury (TBI) in small animal species with particular emphasis on its validity, clinical relevance and reliability. The LFP model, initially described in 1989, has become the most extensively utilized animal model of TBI (to date, 232 PubMed citations), producing both focal and diffuse (mixed) brain injury. Despite subtle variations in injury parameters between laboratories, universal findings are evident across studies, including histological, physiological, metabolic, and behavioral changes that serve to increase the reliability of the model. Moreover, demonstrable histological damage and severity-dependent behavioral deficits, which partially recover over time, validate LFP as a clinically-relevant model of human TBI. The LFP model, also has been used extensively to evaluate potential therapeutic interventions, including resuscitation, pharmacologic therapies, transplantation, and other neuroprotective and neuroregenerative strategies. Although a number of positive studies have identified promising therapies for moderate TBI, the predictive validity of the model may be compromised when findings are translated to severely injured patients. Recently, the clinical relevance of LFP has been enhanced by combining the injury with secondary insults, as well as broadening studies to incorporate issues of gender and age to better approximate the range of human TBI within study design. We conclude that the LFP brain injury model is an appropriate tool to study the cellular and mechanistic aspects of human TBI that cannot be addressed in the clinical setting, as well as for the development and characterization of novel therapeutic interventions. Continued translation of pre-clinical findings to human TBI will enhance the predictive validity of the LFP model, and allow novel neuroprotective and neuroregenerative treatment strategies developed in the laboratory to reach the appropriate TBI patients.

Journal ArticleDOI
TL;DR: Trait forgivingness was negatively correlated with trait anger, hostility, neuroticism, fear, and vengeful rumination and was positively correlated with agreeableness, extraversion, and trait empathy; however, it is suggested that different content of rumination leads to different outcomes after transgressions.
Abstract: Trait forgivingness is the disposition to forgive interpersonal transgressions over time and across situations. We define forgiveness as the replacement of negative unforgiving emotions with positive, other-oriented emotions. Rumination has been suggested as a mediator between forgivingness and emotional outcomes; however, we suggest that different content of rumination leads to different outcomes after transgressions. In four studies of 179, 233, 80, and 66 undergraduate students, trait forgivingness was negatively correlated with trait anger, hostility, neuroticism, fear, and vengeful rumination and was positively correlated with agreeableness, extraversion, and trait empathy. The disposition to ruminate vengefully mediated the relationship between trait forgivingness and (1) anger-related traits and (2) both revenge motivations and state anger following a specific recent transgression, but it did not mediate between forgivingness and (1) fearfulness and (2) avoidance motivations following a specific transgression. Self-hate statements, a proxy for depressive rumination, mediated the relationship between forgivingness and both depression and fearfulness but not the relationship between forgivingness and trait anger. Future research should distinguish the contents of mental rumination following interpersonal transgressions.

Journal ArticleDOI
TL;DR: To map the emergence and scope of eHealth as a topic and to identify its place within the wider health informatics field, as part of a larger review of research and expert analysis pertaining to current evidence, best practice and future trends is commissioned.
Abstract: BACKGROUND: Lack of consensus on the meaning of eHealth has led to uncertainty among academics, policymakers, providers and consumers. This project was commissioned in light of the rising profile of eHealth on the international policy agenda and the emerging UK National Programme for Information Technology (now called Connecting for Health) and related developments in the UK National Health Service. OBJECTIVES: To map the emergence and scope of eHealth as a topic and to identify its place within the wider health informatics field, as part of a larger review of research and expert analysis pertaining to current evidence, best practice and future trends. METHODS: Multiple databases of scientific abstracts were explored in a nonsystematic fashion to assess the presence of eHealth or conceptually related terms within their taxonomies, to identify journals in which articles explicitly referring to eHealth are contained and the topics covered, and to identify published definitions of the concept. The databases were Medline (PubMed), the Cumulative Index of Nursing and Allied Health Literature (CINAHL), the Science Citation Index (SCI), the Social Science Citation Index (SSCI), the Cochrane Database (including Dare, Central, NHS Economic Evaluation Database [NHS EED], Health Technology Assessment [HTA] database, NHS EED bibliographic) and ISTP (now known as ISI proceedings).We used the search query, “Ehealth OR e-health OR e*health”. The timeframe searched was 1997-2003, although some analyses contain data emerging subsequent to this period. This was supplemented by iterative searches of Web-based sources, such as commercial and policy reports, research commissioning programmes and electronic news pages. Definitions extracted from both searches were thematically analyzed and compared in order to assess conceptual heterogeneity. RESULTS: The term eHealth only came into use in the year 2000, but has since become widely prevalent. The scope of the topic was not immediately discernable from that of the wider health informatics field, for which over 320000 publications are listed in Medline alone, and it is not explicitly represented within the existing Medical Subject Headings (MeSH) taxonomy. Applying eHealth as narrative search term to multiple databases yielded 387 relevant articles, distributed across 154 different journals, most commonly related to information technology and telemedicine, but extending to such areas as law. Most eHealth articles are represented on Medline. Definitions of eHealth vary with respect to the functions, stakeholders, contexts and theoretical issues targeted. Most encompass a broad range of medical informatics applications either specified (eg, decision support, consumer health information) or presented in more general terms (eg, to manage, arrange or deliver health care). However the majority emphasize the communicative functions of eHealth and specify the use of networked digital technologies, primarily the Internet, thus differentiating eHealth from the field of medical informatics. While some definitions explicitly target health professionals or patients, most encompass applications for all stakeholder groups. The nature of the scientific and broader literature pertaining to eHealth closely reflects these conceptualizations. CONCLUSIONS: We surmise that the field – as it stands today – may be characterized by the global definitions suggested by Eysenbach and Eng. [J Med Internet Res 2005;7(1):e9]

Journal ArticleDOI
TL;DR: The article uses confirmatory factor analysis (CFA) as a template to explain didactically multilevel structural equation models (ML-SEMS) and to demonstrate the equivalence of general mixed-effects models and ML-SEM.
Abstract: The article uses confirmatory factor analysis (CFA) as a template to explain didactically multilevel structural equation models (ML-SEM) and to demonstrate the equivalence of general mixed-effects models and ML-SEM. An intuitively appealing graphical representation of complex ML-SEMs is introduced that succinctly describes the underlying model and its assumptions. The use of definition variables (i.e., observed variables used to fix model parameters to individual specific data values) is extended to the case of ML-SEMs for clustered data with random slopes. Empirical examples of multilevel CFA and ML-SEM with random slopes are provided along with scripts for fitting such models in SAS Proc Mixed, Mplus, and Mx. Methodological issues regarding estimation of complex ML-SEMs and the evaluation of model fit are discussed. Further potential applications of ML-SEMs are explored.

Journal ArticleDOI
TL;DR: A meta-analysis of the relationship between in vivo brain volume and intelligence found that brain volume is positively correlated with intelligence.

Journal ArticleDOI
TL;DR: The underlying structure of the genetic and environmental risk factors for the anxiety disorders is similar between men and women and can be constrained to equality across male and female study participants.
Abstract: Background The anxiety disorders exhibit high levels of lifetime comorbidity with one another. Understanding the underlying causes of this comorbidity can provide insight into the etiology of the disorders and inform classification and treatment. Objective To explain anxiety disorder comorbidity by examining the structure of the underlying genetic and environmental risk factors. Design Lifetime diagnoses for 6 anxiety disorders (generalized anxiety disorder, panic disorder, agoraphobia, social phobia, animal phobia, and situational phobia) were obtained during personal interviews from a population-based twin registry. Multivariate structural equation modeling that allowed for sex differences was performed. Setting General community sample. Participants More than 5000 members of male-male and female-female twin pairs from the Virginia Adult Twin Study of Psychiatric and Substance Use Disorders. Main Outcome Measures Parameter estimates for best-fitting model. Results The full model, which contained 2 common genetic, shared environmental, and unique environmental factors plus disorder-specific factors, could be constrained to equality across male and female study participants. In the best-fitting model, the genetic influences on anxiety were best explained by 2 additive genetic factors common across the disorders. The first loaded most strongly in generalized anxiety disorder, panic disorder, and agoraphobia, whereas the second loaded primarily in the 2 specific phobias. Social phobia was intermediate in that it was influenced by both genetic factors. A small role for shared environmental influences was observed owing to a single common factor that accounted for less than 12% of the total variance for any disorder. Unique environmental influences could be explained by a single common factor plus disorder-specific effects. Conclusions The underlying structure of the genetic and environmental risk factors for the anxiety disorders is similar between men and women. Genes predispose to 2 broad groups of disorders dichotomized as panic-generalized-agoraphobic anxiety vs the specific phobias. The remaining associations between the disorders are largely explained by a unique environmental factor shared across the disorders and, to a lesser extent, a common shared environmental factor.

Journal ArticleDOI
TL;DR: Interestingly, S1P is involved in cyclooxygenase-2 induction and C1P are required for the activation and translocation of cPLA2, which suggests that these two sphingolipid metabolites may act in concert to regulate production of eicosanoids, important inflammatory mediators.
Abstract: The phosphorylated sphingolipid metabolites sphingosine 1-phosphate (S1P) and ceramide 1-phosphate (C1P) have emerged as potent bioactive agents. Recent studies have begun to define new biological functions for these lipids. Generated by sphingosine kinases and ceramide kinase, they control numerous aspects of cell physiology, including cell survival and mammalian inflammatory responses. Interestingly, S1P is involved in cyclooxygenase-2 induction and C1P is required for the activation and translocation of cPLA2. This suggests that these two sphingolipid metabolites may act in concert to regulate production of eicosanoids, important inflammatory mediators. Whereas S1P functions mainly via G-protein-coupled receptors, C1P appears to bind directly to targets such as cPLA2 and protein phosphatase 1/2A. S1P probably also has intracellular targets, and in plants it appears to directly regulate the G protein alpha subunit GPA1.

Journal ArticleDOI
TL;DR: The RING assay is used to demonstrate that negative geotaxis declines with the age of animals as previously shown in single fly studies and that senescence of negative geOTaxis is sensitive to genetic background.

Journal ArticleDOI
14 Jan 2005-Science
TL;DR: Two classes of gas-phase aluminum-iodine clusters have been identified whose stability and reactivity can be understood in terms of the spherical shell jellium model and the potential synthetic utility of superatom chemistry built upon these motifs is addressed.
Abstract: Two classes of gas-phase aluminum-iodine clusters have been identified whose stability and reactivity can be understood in terms of the spherical shell jellium model. Experimental reactivity studies show that the Al13I –x clusters exhibit pronounced stability for even numbers of I atoms. Theoretical investigations reveal that the enhanced stability is associated with complementary pairs of I atoms occupying the on-top sites on the opposing Al atoms of the Al13– core. We also report the existence of another series, Al14I –x, that exhibits stability for odd numbers of I atoms. This series can be described as consisting of an Al14I –3 core upon which the I atoms occupy on-top locations around the Al atoms. The potential synthetic utility of superatom chemistry built upon these motifs is addressed.

Journal ArticleDOI
TL;DR: Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the rando-based treatment regimens is presented.
Abstract: Source Citation Early Breast Cancer Trialists' Collaborative Group. Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the rando...

Journal ArticleDOI
TL;DR: The gender-specific rate of MDD in this study population is proportional to rates found in community samples with a 1.7:1 prevalence ofMDD in women vs. men which argues against increased treatment seeking in women.

Journal ArticleDOI
TL;DR: Clinical data indicate that secondary caries and restoration fracture are the most common clinical problems and merit further investigation, and a proposed list of materials tests that may predict performance in a variety of clinical factors is presented.

Journal ArticleDOI
TL;DR: High neuroticism appears to be a broad vulnerability factor for comorbid psychiatric disorders, and novelty seeking is modestly important forComorbid externalising disorders.
Abstract: Background We know little about the degree to which comorbidity, socommonly seen among psychiatric disorders, arises from variation in normal personality. Aims To study the degree to which variation in normal personality accounts for the comorbidity of eight common psychiatric and substance use disorders. Method Internalising disorders (major depression, generalised anxiety and panic disorders, phobias), externalising disorders (alcohol and drug dependence, antisocial personality and conduct disorders) and personality dimensions of neuroticism, extraversion and novelty seeking were assessed in 7588 participants from a population-based twin registry. The proportion of comorbidity explained by each personality dimension was calculated using structural equation modelling. Results Neuroticism accounted for the highest proportion of comorbidity within internalising disorders (20–45%) and between internalising and externalising disorders (19–88%). Variation in neuroticism and novelty seeking each accounted for a modest proportion (10–12% and 7–14%, respectively) of the comorbidity within externalising disorders. Extraversion contributed negligibly. Conclusions High neuroticism appears to be a broad vulnerability factor for comorbid psychiatric disorders. Novelty seeking is modestly important for comorbid externalising disorders.

Journal ArticleDOI
TL;DR: The results are consistent with findings on seasonal affective disorder, and suggest that pleasant weather improves mood and broadens cognition in the spring because people have been deprived of such weather during the winter.
Abstract: Prior studies on the association between weather and psychological changes have produced mixed results. In part, this inconsistency may be because weather's psychological effects are moderated by two important factors: the season and time spent outside. In two correlational studies and an experiment manipulating participants' time outdoors (total N = 605), pleasant weather (higher temperature or barometric pressure) was related to higher mood, better memory, and "broadened" cognitive style during the spring as time spent outside increased. The same relationships between mood and weather were not observed during other times of year, and indeed hotter weather was associated with lower mood in the summer. These results are consistent with findings on seasonal affective disorder, and suggest that pleasant weather improves mood and broadens cognition in the spring because people have been deprived of such weather during the winter.

Journal ArticleDOI
TL;DR: The screen for NAP in the NCS-R greatly improved on previous epidemiological surveys in reducing false positives, but coding of open-ended screening scale responses was still needed to achieve accurate prediction.

Journal ArticleDOI
TL;DR: Patients' expanding needs for decision support and the challenges clinicians and health systems face in meeting those needs are outlined and 2 categories of solutions to facilitate informed choice are explored: expanded information resources for decisionSupport and the coupling of information with decision counseling.
Abstract: Ours is an era in which patients seek greater engagement in health care choices, increasing the demand for high-quality information about clinical options. Providing support for informed choice is not straightforward, however, because of challenges faced by clinicians, health systems, and consumers. Greater use of written or electronic tools can help to clarify choices for patients, but decision aids cannot replace the human element in facilitating informed choice. The ideal solution is to couple information with high-quality decision counseling to help patients understand the potential risks, benefits, and uncertainties of clinical options and to assist them in selecting the option that best accommodates their personal preferences. Decision counseling can be offered by 3 types of providers: clinicians who lack formal informed-choice training ("usual care"), clinicians with formal informed-choice training, or trained third parties who function as impartial decision counselors. Controlled studies are needed to determine which model is best, but none appears to be ideal. The health care system cannot truly support informed decision making without correcting the underlying obstacles that impede patient access to needed information. New information technology solutions, training programs, and reimbursement schemes are necessary. Patient demand for guidance will only increase as clinical options multiply and the world of information continues its rapid growth. Today's health care system is unprepared for the convergence of these 2 burgeoning domains, and the need to address systemic deficiencies will grow more urgent over time.

Journal ArticleDOI
TL;DR: 4D radiotherapy planning for DMLC-based respiratory motion tracking is feasible and may offer tumor dose escalation and/or a reduction in treatment-related complications, however, 4D planning requires new planning tools, such as deformable registration and automated treatment planning on multiple CT image sets.
Abstract: Four-dimensional (4D) radiotherapy is the explicit inclusion of the temporal changes in anatomy during the imaging, planning, and delivery of radiotherapy. Temporal anatomic changes can occur for many reasons, though the focus of the current investigation is respiration motion for lung tumors. The aim of this study was to develop 4D radiotherapy treatment-planning methodology for DMLC-based respiratory motion tracking. A 4D computed tomography (CT) scan consisting of a series of eight 3D CT image sets acquired at different respiratory phases was used for treatment planning. Deformable image registration was performed to map each CT set from the peak-inhale respiration phase to the CT image sets corresponding to subsequent respiration phases. Deformable registration allows the contours defined on the peak-inhale CT to be automatically transferred to the other respiratory phase CT image sets. Treatment planning was simultaneously performed on each of the eight 3D image sets via automated scripts in which the MLC-defined beam aperture conforms to the PTV (which in this case equaled the GTV due to CT scan length limitations) plus a penumbral margin at each respiratory phase. The dose distribution from each respiratory phase CT image set was mapped back to the peak-inhale CT image set for analysis. The treatment intent of 4D planning is that the radiation beam defined by the DMLC tracks the respiration-induced target motion based on a feedback loop including the respiration signal to a real-time MLC controller. Deformation with respiration was observed for the lung tumor and normal tissues. This deformation was verified by examining the mapping of high contrast objects, such as the lungs and cord, between image sets. For the test case, dosimetric reductions for the cord, heart, and lungs were found for 4D planning compared with 3D planning. 4D radiotherapy planning for DMLC-based respiratory motion tracking is feasible and may offer tumor dose escalation and/or a reduction in treatment-related complications. However, 4D planning requires new planning tools, such as deformable registration and automated treatment planning on multiple CT image sets.