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Showing papers by "San Diego State University published in 2009"


Journal ArticleDOI
TL;DR: A series of improvements to the spectroscopic reductions are described, including better flat fielding and improved wavelength calibration at the blue end, better processing of objects with extremely strong narrow emission lines, and an improved determination of stellar metallicities.
Abstract: This paper describes the Seventh Data Release of the Sloan Digital Sky Survey (SDSS), marking the completion of the original goals of the SDSS and the end of the phase known as SDSS-II. It includes 11,663 deg^2 of imaging data, with most of the ~2000 deg^2 increment over the previous data release lying in regions of low Galactic latitude. The catalog contains five-band photometry for 357 million distinct objects. The survey also includes repeat photometry on a 120° long, 2°.5 wide stripe along the celestial equator in the Southern Galactic Cap, with some regions covered by as many as 90 individual imaging runs. We include a co-addition of the best of these data, going roughly 2 mag fainter than the main survey over 250 deg^2. The survey has completed spectroscopy over 9380 deg^2; the spectroscopy is now complete over a large contiguous area of the Northern Galactic Cap, closing the gap that was present in previous data releases. There are over 1.6 million spectra in total, including 930,000 galaxies, 120,000 quasars, and 460,000 stars. The data release includes improved stellar photometry at low Galactic latitude. The astrometry has all been recalibrated with the second version of the USNO CCD Astrograph Catalog, reducing the rms statistical errors at the bright end to 45 milliarcseconds per coordinate. We further quantify a systematic error in bright galaxy photometry due to poor sky determination; this problem is less severe than previously reported for the majority of galaxies. Finally, we describe a series of improvements to the spectroscopic reductions, including better flat fielding and improved wavelength calibration at the blue end, better processing of objects with extremely strong narrow emission lines, and an improved determination of stellar metallicities.

5,665 citations


Journal ArticleDOI
10 Jul 2009-Science
TL;DR: The lack of similarity between the 2009 A(H1N1) virus and its nearest relatives indicates that its gene segments have been circulating undetected for an extended period as mentioned in this paper.
Abstract: Since its identification in April 2009, an A(H1N1) virus containing a unique combination of gene segments from both North American and Eurasian swine lineages has continued to circulate in humans. The lack of similarity between the 2009 A(H1N1) virus and its nearest relatives indicates that its gene segments have been circulating undetected for an extended period. Its low genetic diversity suggests that the introduction into humans was a single event or multiple events of similar viruses. Molecular markers predictive of adaptation to humans are not currently present in 2009 A(H1N1) viruses, suggesting that previously unrecognized molecular determinants could be responsible for the transmission among humans. Antigenically the viruses are homogeneous and similar to North American swine A(H1N1) viruses but distinct from seasonal human A(H1N1).

2,393 citations


Journal ArticleDOI
TL;DR: This first comprehensive examination of built-environment measures demonstrates considerable progress over the past decade, showing diverse environmental variables available that use multiple modes of assessment.

1,195 citations


Journal ArticleDOI
TL;DR: Climate change mitigation in transport should benefit public health substantially and policies to increase the acceptability, appeal, and safety of active urban travel, and discourage travel in private motor vehicles would provide larger health benefits than would policies that focus solely on lower-emission motor vehicles.

1,013 citations


Journal ArticleDOI
TL;DR: A review of the literature on liquid phase sintering can be found in this paper, with a focus on the densification and microstructure evolution events of a mixture of powders.
Abstract: Liquid phase sintering (LPS) is a process for forming high performance, multiple-phase components from powders. It involves sintering under conditions where solid grains coexist with a wetting liquid. Many variants of LPS are applied to a wide range of engineering materials. Example applications for this technology are found in automobile engine connecting rods and high-speed metal cutting inserts. Scientific advances in understanding LPS began in the 1950s. The resulting quantitative process models are now embedded in computer simulations to enable predictions of the sintered component dimensions, microstructure, and properties. However, there are remaining areas in need of research attention. This LPS review, based on over 2,500 publications, outlines what happens when mixed powders are heated to the LPS temperature, with a focus on the densification and microstructure evolution events.

940 citations


Journal ArticleDOI
TL;DR: This study demonstrated the feasibility of international PA surveillance, and showed that IPAQ is an acceptable surveillance instrument, at least within countries, if assessment methods are used consistently over time, trend data will inform countries about the success of their efforts to promote physical activity.
Abstract: Physical activity (PA) is one of the most important factors for improving population health, but no standardised systems exist for international surveillance. The International Physical Activity Questionnaire (IPAQ) was developed for international surveillance. The purpose of this study was a comparative international study of population physical activity prevalence across 20 countries. Between 2002–2004, a standardised protocol using IPAQ was used to assess PA participation in 20 countries [total N = 52,746, aged 18–65 years]. The median survey response rate was 61%. Physical activity levels were categorised as "low", "moderate" and "high". Age-adjusted prevalence estimates are presented by sex. The prevalence of "high PA" varied from 21–63%; in eight countries high PA was reported for over half of the adult population. The prevalence of "low PA" varied from 9% to 43%. Males more frequently reported high PA than females in 17 of 20 countries. The prevalence of low PA ranged from 7–41% among males, and 6–49% among females. Gender differences were noted, especially for younger adults, with males more active than females in most countries. Markedly lower physical activity prevalence (10% difference) with increasing age was noted in 11 of 19 countries for males, but only in three countries for women. The ways populations accumulated PA differed, with some reporting mostly vigorous intensity activities and others mostly walking. This study demonstrated the feasibility of international PA surveillance, and showed that IPAQ is an acceptable surveillance instrument, at least within countries. If assessment methods are used consistently over time, trend data will inform countries about the success of their efforts to promote physical activity.

859 citations


Journal ArticleDOI
TL;DR: It is suggested that implicit stereotypes and sex differences in science participation and performance are mutually reinforcing, contributing to the persistent gender gap in science engagement.
Abstract: About 70% of more than half a million Implicit Association Tests completed by citizens of 34 countries revealed expected implicit stereotypes associating science with males more than with females. We discovered that nation-level implicit stereotypes predicted nation-level sex differences in 8th-grade science and mathematics achievement. Self-reported stereotypes did not provide additional predictive validity of the achievement gap. We suggest that implicit stereotypes and sex differences in science participation and performance are mutually reinforcing, contributing to the persistent gender gap in science engagement.

833 citations


Journal ArticleDOI
TL;DR: In this article, the degree to which firms' strategic market planning is driven by customer and compressive factors is analyzed. But market orientation (MO) and entrepreneurial orientation (EO) are correlated and distinct constructs.
Abstract: Market orientation (MO) and entrepreneurial orientation (EO) are correlated, but distinct constructs. MO reflects the degree to which firms' strategic market planning is driven by customer and comp...

794 citations


Book
01 Jan 2009
TL;DR: The authors of "The Narcissism Epidemic" as discussed by the authors argue that "Narcissism" is everywhere in the culture and it's what's making people depressed, lonely, and buried under piles of debt.
Abstract: Narcissism -- a very positive and inflated view of the self -- is everywhere. It's what you have if you're a politician and you've strayed from your wife, and it's whyEfive times as many Americans undergo plastic surgery and cosmetic procedures today than did just ten years ago. It's the value that parents teach their children with song lyrics like "I am special. Look at me," the skill teenagers and young adults obsessively hone on Facebook and MySpace, and the reason high school students physically beat classmates and then broadcast their violence on YouTube for all to see. It's the message preached by prosperity gospel and the vacuous ethos spread by celebrity newsmakers. And it's what's making people depressed, lonely, and buried under piles of debt. Jean M. Twenge's influential and controversial first book, "Generation Me," generated a national debate with its trenchant depiction of the challenges twenty- and thirtysomethings face emotionally and professionally in today's world -- and the fallout these issues create for older generations as well as employers. Now, Dr. Twenge is on to a new incendiary topic that has repercussions for every age-group and class: the pernicious spread of narcissism in today's culture and its catastrophic effects. Dr. Twenge joins forces with W. Keith Campbell, Ph.D., a nationally recognized expert on narcissism, for "The Narcissism Epidemic," their eye-opening exposition of the alarming rise of narcissism -- and they show how to stop it. Every day, you encounter the real costs of narcissism: in your relationships and family, in the workplace and the economy at large, in schools that fail to teach necessary skills, in culture, and in politics. Even the world economy has been damaged by risky, unrealistic overconfidence. Filled with arresting anecdotes that illustrate the hold narcissism has on us today -- from people hiring fake paparazzi in order to experience feeling famous to college students who won't leave a professor's office until their B+ becomes an A -- "The Narcissism Epidemic" is at once a riveting window into the consequences of narcissism, a probing analysis of the culture at large, and a prescription to combat the widespread problems caused by narcissism. As a society, we have a chance to slow the epidemic of narcissism once we learn to identify it, minimize the forces that sustain and transmit it, and treat it where we find it. Drawing on their own extensive research as well as decades of other experts' studies, Drs. Twenge and Campbell show us how.

753 citations


Journal ArticleDOI
TL;DR: Males were more likely than females to report negative collective self-esteem and SNS use for social compensation and social identity gratifications, suggesting that those who felt negatively about their social group used SNS as an alternative to communicating with other group members.
Abstract: This study assessed motives for social network site (SNS) use, group belonging, collective self-esteem, and gender effects among older adolescents. Communication with peer group members was the most important motivation for SNS use. Participants high in positive collective self-esteem were strongly motivated to communicate with peer group via SNS. Females were more likely to report high positive collective self-esteem, greater overall use, and SNS use to communicate with peers. Females also posted higher means for group-in-self, passing time, and entertainment. Negative collective self-esteem correlated with social compensation, suggesting that those who felt negatively about their social group used SNS as an alternative to communicating with other group members. Males were more likely than females to report negative collective self-esteem and SNS use for social compensation and social identity gratifications.

713 citations


Journal ArticleDOI
TL;DR: The analysis showed that three variables had a significant effect on initial trust in mobile banking, and the perception of initial trust and relative benefits was vital in promoting personal intention to make use of related services, whereas the reputation as a firm characteristics variable failed to attract people to mobile banking.
Abstract: Mobile banking is an emerging application of mobile commerce that could become an additional revenue source to both banks and telecom service providers. It is a form of service convergence enabled by innovative technologies. Despite the alleged benefits of mobile banking, its acceptance has been short of industry expectations. One plausible explanation may be consumers' initial lack of trust in available services. The objective of our research is to reveal the mechanisms associated with the initial formation of people's trust in mobile banking and intention to use the service. For this, we attempt to understand the effect of four antecedent variables (structural assurances, relative benefits, personal propensity to trust and firm reputation) on shaping a person's initial trust in mobile banking and its usage intention. They represent four types of trust-inducing forces: institutional offering (structural assurances), cognition (perceived benefits), personality (personal propensity) and firm characteristics (firm reputation). We examine individual significance of the selected antecedents and also their comparative reliability in explaining the two exogenous variables. The technical basis of our empirical research is the innovative mobile banking solution that uses cellphones with a built-in smart chipset. The survey data are analyzed using structural equation modelling. The analysis showed that three variables (relative benefits, propensity to trust and structural assurances) had a significant effect on initial trust in mobile banking. Also, the perception of initial trust and relative benefits was vital in promoting personal intention to make use of related services. However, contrary to our expectation, the reputation as a firm characteristics variable failed to attract people to mobile banking.

Journal ArticleDOI
TL;DR: Environment, policy, and multilevel strategies for improving diet, physical activity, and obesity control are recommended based on a rapidly growing body of research and the collective wisdom of leading expert organizations.
Abstract: Context: Environmental, policy, and societal changes are important contributors to the rapid rise in obesity over the past few decades, and there has been substantial progress toward identifying environmental and policy factors related to eating and physical activity that can point toward solutions. This article is a status report on research on physical activity and food environments, and it suggests how these findings can be used to improve diet and physical activity and to control or reduce obesity. Methods: This article summarizes and synthesizes recent reviews and provides examples of representative studies. It also describes ongoing innovative interventions and policy change efforts that were identified through conference presentations, media coverage, and websites. Findings: Numerous cross-sectional studies have consistently demonstrated that some attributes of built and food environments are associated with physical activity, healthful eating, and obesity. Residents of walkable neighborhoods who have good access to recreation facilities are more likely to be physically active and less likely to be overweight or obese. Residents of communities with ready access to healthy foods also tend to have more healthful diets. Disparities in environments and policies that disadvantage low-income communities and racial minorities have been documented as well. Evidence from multilevel studies, prospective research, and quasi-experimental evaluations of environmental changes are just beginning to emerge. Conclusions: Environment, policy, and multilevel strategies for improving diet, physical activity, and obesity control are recommended based on a rapidly growing body of research and the collective wisdom of leading expert organizations. A public health imperative to identify and implement solutions to the obesity epidemic warrants the use of the most promising strategies while continuing to build the evidence base.

Journal ArticleDOI
TL;DR: This research highlights the need to understand more fully the rationale behind the rapid decline in physical activity in middle-aged people over a longer period of time.
Abstract: Sarah L. Booth, Ph.D., Vitamin K Laboratory, Jean Mayer USDAHuman Nutrition Research Center on Aging at Tufts University, Boston, MA; James F. Sallis, Ph.D., F.A.C.S.M., Department ofPsychology, San Diego State University, San Diego, CA; Cheryl Ritenbaugh, Ph.D., M.P.H., Kaiser Permanente Center for Health Research, Portland, O R James 0. Hill, Ph.D., Center for Human Nutrition, University of Colorado Health Sciences Center, Denver, CO; Leann L. Birch, Ph.D., Department ofHuman Development and Family Studies, Pennsylvania State University, University Park, PA; Lawrence D. Frank, Ph.D., College OfArchitecture, Georgia Institute of Technology, Atlanta, GA; Karen Glanz, Ph.D., M.P.H., Cancer Research Center of Hawaii, University of Hawaii, Honolulu, HI; David A. Himmelgreen, Ph.D., Department ofAnthropology, University of South Florida, Tampa, FL; Michael Mudd, Corporate Affairs, Kraft Foods, Inc., Northfield, IL; Barry M. Popkin, Ph.D., Department ofNutrition, Carolina Population Center, University of North Carolina, Chapel Hill, NC; Karyl A. Rickard, Ph.D., R.D., C.S.P., F.A.D.A., Nutrition and Dietetics Program, School ofAllied Health Sciences, Indiana University School of Medicine, Indianapolis, IN; Sachiko St. Jeor, Ph.D., R.D., Nutrition Education and Research Program, University of Nevada School of Medicine, Reno, W, Nicholas P. Hays, M.S., Energy Metabolism Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA.

Journal ArticleDOI
TL;DR: Text messages might prove to be a productive channel of communication to promote behaviors that support weight loss in overweight adults.
Abstract: Background: To our knowledge, no studies have evaluated whether weight loss can be promoted in overweight adults through the use of an intervention that is largely based on daily SMS (Short Message Service: text) and MMS (Multimedia Message Service: small picture) messages transmitted via mobile phones. Objective: This paper describes the development and evaluation of a text message-based intervention designed to help individuals lose or maintain weight over 4 months. Methods: The study was a randomized controlled trial, with participants being exposed to one of the following two conditions, lasting 16 weeks: (1) receipt of monthly printed materials about weight control; (2) an intervention that included personalized SMS and MMS messages sent two to five times daily, printed materials, and brief monthly phone calls from a health counselor. The primary outcome was weight at the end of the intervention. A mixed-model repeated-measures analysis compared the effect of the intervention group to the comparison group on weight status over the 4-month intervention period. Analysis of covariance (ANCOVA) models examined weight change between baseline and 4 months after adjusting for baseline weight, sex, and age. Results: A total of 75 overweight men and women were randomized into one of the two groups, and 65 signed the consent form, completed the baseline questionnaire, and were included in the analysis. At the end of 4 months, the intervention group (n = 33) lost more weight than the comparison group (?1.97 kg difference, 95% CI ?0.34 to ?3.60 kg, P = .02) after adjusting for sex and age. Intervention participants' adjusted average weight loss was 2.88 kg (3.16%). At the end of the study, 22 of 24 (92%) intervention participants stated that they would recommend the intervention for weight control to friends and family. Conclusions: Text messages might prove to be a productive channel of communication to promote behaviors that support weight loss in overweight adults. Trial Registration: Clinicaltrials.gov NCT00415870; http://clinicaltrials.gov/ct2/show/NCT00415870 (Archived by WebCite at http://www.webcitation.org/5dnolbkFt) [J Med Internet Res 2009;11(1):e1]

Journal ArticleDOI
TL;DR: It was concluded that living in walkable neighborhoods was associated with more physical activity and lower overweight/obesity but not with other benefits, and lower- and higher-income groups benefited similarly from living in high-walkability neighborhoods.

Journal ArticleDOI
TL;DR: Comparison of the glycoside hydrolase and cellulosome functional genes revealed that in the rumen microbiome, initial colonization of fiber appears to be by organisms possessing enzymes that attack the easily available side chains of complex plant polysaccharides and not the more recalcitrant main chains, especially cellulose.
Abstract: The complex microbiome of the rumen functions as an effective system for the conversion of plant cell wall biomass to microbial protein, short chain fatty acids, and gases. As such, it provides a unique genetic resource for plant cell wall degrading microbial enzymes that could be used in the production of biofuels. The rumen and gastrointestinal tract harbor a dense and complex microbiome. To gain a greater understanding of the ecology and metabolic potential of this microbiome, we used comparative metagenomics (phylotype analysis and SEED subsystems-based annotations) to examine randomly sampled pyrosequence data from 3 fiber-adherent microbiomes and 1 pooled liquid sample (a mixture of the liquid microbiome fractions from the same bovine rumens). Even though the 3 animals were fed the same diet, the community structure, predicted phylotype, and metabolic potentials in the rumen were markedly different with respect to nutrient utilization. A comparison of the glycoside hydrolase and cellulosome functional genes revealed that in the rumen microbiome, initial colonization of fiber appears to be by organisms possessing enzymes that attack the easily available side chains of complex plant polysaccharides and not the more recalcitrant main chains, especially cellulose. Furthermore, when compared with the termite hindgut microbiome, there are fundamental differences in the glycoside hydrolase content that appear to be diet driven for either the bovine rumen (forages and legumes) or the termite hindgut (wood).

Journal ArticleDOI
TL;DR: Findings and viewpoints from the scientific binge-drinking literature are summarized, and theoretical implications are discussed on how binge drinking may alter neurophysiological and neurocognitive function.
Abstract: Binge drinking is an increasingly important topic in alcohol research, but the field lacks empirical cohesion and definitional precision. The present review summarizes findings and viewpoints from the scientific binge-drinking literature. Epidemiological studies quantify the seriousness of alcohol-related problems arising from binge drinking, with a growing incidence reported in college-age men over the last 2 years. Experimental studies have found neurocognitive deficits for frontal lobe processing and working memory operations in binge-drinking compared with nonbinge alcohol drinkers. The findings are organized with the goals of providing a useful binge-drinking definition in the context of the empirical results. Theoretical implications are discussed on how binge drinking may alter neurophysiological and neurocognitive function.

Journal ArticleDOI
TL;DR: This work proposes the constant-diversity dynamics model, in which the diversity of prokaryotic populations is preserved by phage predation, and provides supporting evidence for this model from metagenomics, mathematical analysis and computer simulations.
Abstract: Not all isolates of a species contain the same set of genes. In this Opinion article, Rodriguez-Valera and colleagues propose the constant-diversity model to account for these differences. In this model, predation by phages promotes bacterial diversity and allows more efficient use of the nutrients in the environment. The remarkable differences that have been detected by metagenomics in the genomes of strains of the same bacterial species are difficult to reconcile with the widely accepted paradigm that periodic selection within bacterial populations will regularly purge genomic diversity by clonal replacement. We have found that many of the genes that differ between strains affect regions that are potential phage recognition targets. We therefore propose the constant-diversity dynamics model, in which the diversity of prokaryotic populations is preserved by phage predation. We provide supporting evidence for this model from metagenomics, mathematical analysis and computer simulations. Periodic selection and phage predation dynamics are not mutually exclusive; we compare their predictions to shed light on the ecological circumstances under which each type of dynamics could predominate.

Journal ArticleDOI
13 May 2009-Nature
TL;DR: A series of recent studies has shown that viruses have the ability to manipulate the life histories and evolution of their hosts in remarkable ways, challenging the understanding of this almost invisible world.
Abstract: Marine viruses affect Bacteria, Archaea and eukaryotic organisms and are major components of the marine food web. Most studies have focused on their role as predators and parasites, but many of the interactions between marine viruses and their hosts are much more complicated. A series of recent studies has shown that viruses have the ability to manipulate the life histories and evolution of their hosts in remarkable ways, challenging our understanding of this almost invisible world.

Journal ArticleDOI
TL;DR: This article addresses 8 specific questions about reliability, item difficulty, frequency of administration, learning effects, social desirability, validity, judgments of self-care adequacy, clinically relevant change, and comparability of the various versions of the SCHFI.
Abstract: Background The Self-care of Heart Failure Index (SCHFI) is a measure of self-care defined as a naturalistic decision-making process involving the choice of behaviors that maintain physiological stability (maintenance) and the response to symptoms when they occur (management). In the 5 years since the SCHFI was published, we have added items, refined the response format of the maintenance scale and the SCHFI scoring procedure, and modified our advice about how to use the scores. Objective The objective of this article was to update users on these changes. Methods In this article, we address 8 specific questions about reliability, item difficulty, frequency of administration, learning effects, social desirability, validity, judgments of self-care adequacy, clinically relevant change, and comparability of the various versions. Results The addition of items to the self-care maintenance scale did not significantly change the coefficient alpha, providing evidence that the structure of the instrument is more powerful than the individual items. No learning effect is associated with repeated administration. Social desirability is minimal. More evidence is provided of the validity of the SCHFI. A score of 70 or greater can be used as the cut-point to judge self-care adequacy, although evidence is provided that benefit occurs at even lower levels of self-care. A change in a scale score more than one-half of an SD is considered clinically relevant. Because of the standardized scores, results obtained with prior versions can be compared with those from later versions. Conclusion The SCHFI v.6 is ready to be used by investigators. By publication in this format, we are putting the instrument in the public domain; permission is not required to use the SCHFI.

Journal ArticleDOI
TL;DR: The authors tested the hypothesis that an 8-session attention modification program would decrease attention bias to threat and reduce symptoms of GAD and suggest that altering attention mechanisms may effectively reduce anxiety.
Abstract: Research suggests that individuals with generalized anxiety disorder (GAD) show an attention bias for threat-relevant information. However, few studies have examined the causal role of attention bias in the maintenance of anxiety and whether modification of such biases may reduce pathological anxiety symptoms. In the present article, the authors tested the hypothesis that an 8-session attention modification program would (a) decrease attention bias to threat and (b) reduce symptoms of GAD. Participants completed a probe detection task by identifying letters (E or F) replacing one member of a pair of words. The authors trained attention by including a contingency between the location of the probe and the nonthreat word in one group (Attention Modification Program; AMP) and not in the other (attention control condition; ACC). Participants in the AMP showed change in attention bias and a decrease in anxiety, as indicated by both self-report and interviewer measures. These effects were not present in the ACC group. These results are consistent with the hypothesis that attention plays a causal role in the maintenance of GAD and suggest that altering attention mechanisms may effectively reduce anxiety.

Journal ArticleDOI
TL;DR: This collection of laboratory protocols describes the steps to collect viruses from various samples with the specific aim of generating viral metagenome sequence libraries (viromes) using several concentration, purification, extraction, sequencing and heuristic bioinformatic methods.
Abstract: This collection of laboratory protocols describes the steps to collect viruses from various samples with the specific aim of generating viral metagenome sequence libraries (viromes). Viral metagenomics, the study of uncultured viral nucleic acid sequences from different biomes, relies on several concentration, purification, extraction, sequencing and heuristic bioinformatic methods. No single technique can provide an all-inclusive approach, and therefore the protocols presented here will be discussed in terms of hypothetical projects. However, care must be taken to individualize each step depending on the source and type of viral-particles. This protocol is a description of the processes we have successfully used to: (i) concentrate viral particles from various types of samples, (ii) eliminate contaminating cells and free nucleic acids and (iii) extract, amplify and purify viral nucleic acids. Overall, a sample can be processed to isolate viral nucleic acids suitable for high-throughput sequencing in approximately 1 week.

Journal ArticleDOI
03 Jun 2009-JAMA
TL;DR: The CB prevention program had a significant prevention effect through the 9-month follow-up period based on both clinical diagnoses and self-reported depressive symptoms, but this effect was not evident for adolescents with a currently depressed parent.
Abstract: Context Adolescent offspring of depressed parents are at markedly increased risk of developing depressive disorders. Although some smaller targeted prevention trials have found that depression risk can be reduced, these results have yet to be replicated and extended to large-scale, at-risk populations in different settings. Objective To determine the effects of a group cognitive behavioral (CB) prevention program compared with usual care in preventing the onset of depression. Design, Setting, and Participants A multicenter randomized controlled trial conducted in 4 US cities in which 316 adolescent (aged 13-17 years) offspring of parents with current or prior depressive disorders were recruited from August 2003 through February 2006. Adolescents had a past history of depression, current elevated but subdiagnostic depressive symptoms, or both. Assessments were conducted at baseline, after the 8-week intervention, and after the 6-month continuation phase. Intervention Adolescents were randomly assigned to the CB prevention program consisting of 8 weekly, 90-minute group sessions followed by 6 monthly continuation sessions or assigned to receive usual care alone. Main Outcome Measure Rate and hazard ratio (HR) of a probable or definite depressive episode (ie, depressive symptom rating score of ≥4) for at least 2 weeks as diagnosed by clinical interviewers. Results Through the postcontinuation session follow-up, the rate and HR of incident depressive episodes were lower for those in the CB prevention program than for those in usual care (21.4% vs 32.7%; HR, 0.63; 95% confidence interval [CI], 0.40-0.98). Adolescents in the CB prevention program also showed significantly greater improvement in self-reported depressive symptoms than those in usual care (coefficient, −1.1; z = −2.2; P = .03). Current parental depression at baseline moderated intervention effects (HR, 5.98; 95% CI, 2.29-15.58; P = .001). Among adolescents whose parents were not depressed at baseline, the CB prevention program was more effective in preventing onset of depression than usual care (11.7% vs 40.5%; HR, 0.24; 95% CI, 0.11-0.50), whereas for adolescents with a currently depressed parent, the CB prevention program was not more effective than usual care in preventing incident depression (31.2% vs 24.3%; HR, 1.43; 95% CI, 0.76-2.67). Conclusion The CB prevention program had a significant prevention effect through the 9-month follow-up period based on both clinical diagnoses and self-reported depressive symptoms, but this effect was not evident for adolescents with a currently depressed parent. Trial Registration clinicaltrials.gov Identifier: NCT00073671

Journal ArticleDOI
TL;DR: It is found that outer membrane fusion can be readily visualized in OPA1-null mouse cells in vivo, but these events do not progress to inner membrane fusion, indicating that mammalian mitofusins and OPA2 mediate distinct sequential fusion steps that are readily uncoupled, in contrast to the situation in yeast.
Abstract: Mitochondrial fusion requires the coordinated fusion of the outer and inner membranes. Three large GTPases—OPA1 and the mitofusins Mfn1 and Mfn2—are essential for the fusion of mammalian mitochondria. OPA1 is mutated in dominant optic atrophy, a neurodegenerative disease of the optic nerve. In yeast, the OPA1 ortholog Mgm1 is required for inner membrane fusion in vitro; nevertheless, yeast lacking Mgm1 show neither outer nor inner membrane fusion in vivo, because of the tight coupling between these two processes. We find that outer membrane fusion can be readily visualized in OPA1-null mouse cells in vivo, but these events do not progress to inner membrane fusion. Similar defects are found in cells lacking prohibitins, which are required for proper OPA1 processing. In contrast, double Mfn-null cells show neither outer nor inner membrane fusion. Mitochondria in OPA1-null cells often contain multiple matrix compartments bounded together by a single outer membrane, consistent with uncoupling of outer versus inner membrane fusion. In addition, unlike mitofusins and yeast Mgm1, OPA1 is not required on adjacent mitochondria to mediate membrane fusion. These results indicate that mammalian mitofusins and OPA1 mediate distinct sequential fusion steps that are readily uncoupled, in contrast to the situation in yeast.

Journal ArticleDOI
TL;DR: A conceptual model is developed to evaluate the importance of variation in exposure due to individual human movements for pathogen transmission, focusing on mosquito-borne dengue virus, showing that the relevance of human movement at a particular scale depends on vector behavior.
Abstract: Background Human movement is a key behavioral factor in many vector-borne disease systems because it influences exposure to vectors and thus the transmission of pathogens. Human movement transcends spatial and temporal scales with different influences on disease dynamics. Here we develop a conceptual model to evaluate the importance of variation in exposure due to individual human movements for pathogen transmission, focusing on mosquito-borne dengue virus. Methodology and Principal Findings We develop a model showing that the relevance of human movement at a particular scale depends on vector behavior. Focusing on the day-biting Aedes aegypti, we illustrate how vector biting behavior combined with fine-scale movements of individual humans engaged in their regular daily routine can influence transmission. Using a simple example, we estimate a transmission rate (R0) of 1.3 when exposure is assumed to occur only in the home versus 3.75 when exposure at multiple locations—e.g., market, friend's—due to movement is considered. Movement also influences for which sites and individuals risk is greatest. For the example considered, intriguingly, our model predicts little correspondence between vector abundance in a site and estimated R0 for that site when movement is considered. This illustrates the importance of human movement for understanding and predicting the dynamics of a disease like dengue. To encourage investigation of human movement and disease, we review methods currently available to study human movement and, based on our experience studying dengue in Peru, discuss several important questions to address when designing a study. Conclusions/Significance Human movement is a critical, understudied behavioral component underlying the transmission dynamics of many vector-borne pathogens. Understanding movement will facilitate identification of key individuals and sites in the transmission of pathogens such as dengue, which then may provide targets for surveillance, intervention, and improved disease prevention.


Journal ArticleDOI
TL;DR: This article reviews the extant literature on neurocognition, brain structure, and brain function in adolescent substance users with an emphasis on the most commonly used substances, and in the context of ongoing neuromaturational processes.
Abstract: Adolescence is a unique period in neurodevelopment. Alcohol and marijuana use are common. Recent research has indicated that adolescent substance users show abnormalities on measures of brain functioning, which is linked to changes in neurocognition over time. Abnormalities have been seen in brain structure volume, white matter quality, and activation to cognitive tasks, even in youth with as little as 1-2 years of heavy drinking and consumption levels of 20 drinks per month, especially if > 4-5 drinks are consumed on a single occasion. Heavy marijuana users show some subtle anomalies too, but generally not the same degree of divergence from demographically similar non-using adolescents. This article reviews the extant literature on neurocognition, brain structure, and brain function in adolescent substance users with an emphasis on the most commonly used substances, and in the context of ongoing neuromaturational processes. Methodological and treatment implications are provided.

Journal ArticleDOI
TL;DR: Results revealed that the AMP facilitated attention disengagement from threat from pre- to post assessment and reduced clinician- and self-reported symptoms of social anxiety relative to the ACC, suggesting that computerized attention training procedures may be beneficial for treating social phobia.
Abstract: The authors conducted a randomized, double-blind placebo-controlled trial to examine the efficacy of an attention training procedure in reducing symptoms of social anxiety in 44 individuals diagnosed with generalized social phobia (GSP) Attention training comprised a probe detection task in which pictures of faces with either a threatening or neutral emotional expression cued different locations on the computer screen In the attention modification program (AMP), participants responded to a probe that always followed neutral faces when paired with a threatening face, thereby directing attention away from threat In the attention control condition (ACC), the probe appeared with equal frequency in the position of the threatening and neutral faces Results revealed that the AMP facilitated attention disengagement from threat from pre- to postassessment and reduced clinician- and self-reported symptoms of social anxiety relative to the ACC The percentage of participants no longer meeting Diagnostic and Statistical Manual (4th ed) criteria for GSP at postassessment was 50% in the AMP and 14% in the ACC Symptom reduction in the AMP group was maintained during 4-month follow-up assessment These results suggest that computerized attention training procedures may be beneficial for treating social phobia

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TL;DR: It is suggested that the bacteria promote algal assimilation of iron by facilitating photochemical redox cycling of this critical nutrient, and mutualistic sharing of iron and fixed carbon has important implications toward understanding of the close beneficial interactions between marine bacteria and phytoplankton.
Abstract: Marine microalgae support world fisheries production and influence climate through various mechanisms. They are also responsible for harmful blooms that adversely impact coastal ecosystems and economies. Optimal growth and survival of many bloom-forming microalgae, including climatically important dinoflagellates and coccolithophores, requires the close association of specific bacterial species, but the reasons for these associations are unknown. Here, we report that several clades of Marinobacter ubiquitously found in close association with dinoflagellates and coccolithophores produce an unusual lower-affinity dicitrate siderophore, vibrioferrin (VF). Fe-VF chelates undergo photolysis at rates that are 10–20 times higher than siderophores produced by free-living marine bacteria, and unlike the latter, the VF photoproduct has no measurable affinity for iron. While both an algal-associated bacterium and a representative dinoflagellate partner, Scrippsiella trochoidea, used iron from Fe-VF chelates in the dark, in situ photolysis of the chelates in the presence of attenuated sunlight increased bacterial iron uptake by 70% and algal uptake by >20-fold. These results suggest that the bacteria promote algal assimilation of iron by facilitating photochemical redox cycling of this critical nutrient. Also, binary culture experiments and genomic evidence suggest that the algal cells release organic molecules that are used by the bacteria for growth. Such mutualistic sharing of iron and fixed carbon has important implications toward our understanding of the close beneficial interactions between marine bacteria and phytoplankton, and the effect of these interactions on algal blooms and climate.

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TL;DR: In this paper, the authors develop and test a theoretical model of the effects of outside directors' human and social capital on firm growth, and find that outside directors membership on multiple boards, industry-specific managerial experience, and firm-specific founding experience have strong additive and interactive effects.