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Trajectories
Kinds of Trajectories Terms modified by Trajectories Selected AbstractsTHE FUTURE TRAJECTORY OF U.S. CO2 EMISSIONS: THE ROLE OF STATE VS.JOURNAL OF REGIONAL SCIENCE, Issue 1 2007AGGREGATE INFORMATION ABSTRACT This paper provides comparisons of a variety of time-series methods for short-run forecasts of the main greenhouse gas, carbon dioxide, for the United States, using a recently released state-level data set from 1960,2001. We test the out-of-sample performance of univariate and multivariate forecasting models by aggregating state-level forecasts versus forecasting the aggregate directly. We find evidence that forecasting the disaggregate series and accounting for spatial effects drastically improves forecasting performance under root mean squared forecast error loss. Based on the in-sample observations we attempt to explain the emergence of voluntary efforts by states to reduce greenhouse gas emissions. We find evidence that states with decreasing per capita emissions and a "greener" median voter are more likely to push toward voluntary cutbacks in emissions. [source] Using particles for 3D texture sculptingCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 4 2001ich Bene Abstract Particle systems have been used in computer graphics for many different purposes, including visual simulation of fur, grass, hair, and similar fuzzy textures and shapes. The underlying theories used in these algorithms are usually quite complex and are mostly based on simulation of diffuse-limited aggregation, cellular development, reaction-diffusion models, etc. This leads to high time complexity of these algorithms. The purpose of this paper is to show that collision detection and distance keeping among moving particles can generate similar realistic textures efficiently. This approach is easy to implement, sufficiently fast allowing for interactive modeling, and inherits the major features from the previously published techniques. We first construct a scene consisting of generators of particles, attractors, and cutters. The generators generate oriented particles, and the attractors attract or repulse them. When collision with the cutter is detected, the particle performs an action according to its state and position in the 3D space. Every particle has assigned a table of possible actions that is used for solving these critical states. Trajectories of the particles are then used as a resulting shape of the texture. Copyright © 2001 John Wiley & Sons, Ltd. [source] Trajectories for Greening in China: Theory and PracticeDEVELOPMENT AND CHANGE, Issue 1 2006Peter Ho This edited volume argues that China's development poses the greatest ever environmental challenge for the modern world in terms of speed, size and scarcity. The volume is organized around the greening of the Chinese state and society: can the inclusion of sustainable development principles into governance, management and daily practices by social actors lead to sustainable development per se? This introduction sketches the different scholarly camps around greening and sustainable development, ranging from sceptical to radical environmentalism. The contributions demonstrate that China is showing clear signs of greening as new institutions and regulations are created, environmental awareness increases and green technologies are implemented. However, the question remains whether this is sufficient to effectuate long-term sustainable development. The key factors here are the sheer speed of China's economic growth, the size of its population, and the relative scarcity of its natural and mineral resources. Chinese development presents compelling reasons for rethinking the viability of greening. It is necessary to move beyond both alarmist visions of an environmental doomsday, and optimistic notions that incremental changes in technology, institutions and lifestyles are sufficient for sustainability. It might be more fruitful , and not only for China , to consider ,precautionary' rather than ,absolute' limits to growth. [source] Trajectories of resilience over 25 years of individuals who as adolescents consulted for substance misuse and a matched comparison groupADDICTION, Issue 7 2010Peter Larm ABSTRACT Aims To examine trajectories of resilience over 25 years among individuals who as adolescents received treatment for substance misuse, the clinical sample (CS) and a matched general population sample (GP). Design Comparison of the CS and GP over 25 years using Swedish national registers of health care and criminality. Setting A substance misuse clinic for adolescents in an urban area in Sweden. Measurements Resilience was defined as the absence of substance misuse, hospitalizations for physical illnesses related to substance misuse, hospitalization for mental illness and law-abiding behaviour from ages 21 to 45 years. Participants The CS included 701 individuals who as adolescents had consulted a clinic for substance misuse. The GP included 731 individuals selected randomly from the Swedish population and matched for age, sex and birthplace. Findings A total of 52.4% of the GP and 24.4% of the CS achieved resilience in all domains through 25 years. Among the CS, another one-third initially displayed moderate levels of resilience that rose to high levels over time, one-quarter displayed decreasing levels of resilience over time, while 9.3% showed little but improving resilience and 8.8% showed no resilience. Levels of resilience were associated with the severity of substance misuse and delinquency in adolescence. Conclusions Individuals who had presented substance misuse problems in adolescence were less likely to achieve resilience over the subsequent 25 years than was a matched general population sample, and among them, four distinct trajectories of resilience were identified. The severity and type of problems presented in adolescence distinguished the four trajectories. [source] Trajectories of smoking among freshmen college students with prior smoking history and risk for future smoking: data from the University Project Tobacco Etiology Research Network (UpTERN) studyADDICTION, Issue 9 2008Craig R. Colder ABSTRACT Aims Little is known about smoking during the transition to college. The current study examined trajectories of smoking among college freshmen, how trajectories predicted later smoking and the social context of smoking. Design Weekly assessments of daily smoking were collected via the web during the first year of college for a large cohort with a previous history of smoking. Participants and setting A total of 193 college freshmen from a large public university with a previous history of smoking who smoked frequently enough to be included in trajectory analysis. Measurements Measures included weekly reports of daily smoking, family smoking, perceived peer attitudes and smoking, social norms and social smoking environment. Findings Seven trajectories were identified: one of low-level sporadic smoking, one of low-level smoking with a small increase during the year, two classes with a substantial decrease during the year, two classes with relatively small decreases and one class with a substantial increase in smoking. Trajectories of smoking in the freshman year predicted levels of sophomore year smoking, and some social context variables tended to change as smoking increased or decreased for a given trajectory class. Conclusions The transition into college is marked by changes in smoking, with smoking escalating for some students and continuing into the sophomore year. Shifts in social context that support smoking were associated with trajectories of smoking. Despite the focus of developmental models on smoking in early adolescence, the transition into college warrants further investigation as a dynamic period for smoking. [source] Transport of larval jack mackerel (Trachurus japonicus) estimated from trajectories of satellite-tracked drifters and advective velocity fields obtained from sequential satellite thermal images in the eastern East China SeaFISHERIES OCEANOGRAPHY, Issue 6 2002Hee-Yong Kim Abstract Transport processes of jack mackerel (Trachurus japonicus) larvae in the waters off the west coast of Kyushu in the eastern East China Sea, have been investigated using satellite-tracked surface drifters and consecutive satellite thermal images. Trajectories of drifters describe northward flows over the continental shelf, eastward flows of the Kuroshio south-west of Kyushu, and a weak clockwise gyre off the west coast of Kyushu. In particular, the clockwise gyre causes the entrainment of jack mackerel larvae into the waters off the west coast of Kyushu. Consecutive satellite thermal images help to elucidate the northward warm water intrusion from the Kuroshio front south-west of Kyushu. Particle trajectories using sea surface current fields computed with the Maximum Cross Correlation (MCC) technique also reveal that the transport of jack mackerel larvae into the nursery ground off the west coast of Kyushu caused by the anti-cyclonic gyre and the warm streamers are an important process for successful recruitment. [source] Trajectories of Multiculturalism in Germany, the Netherlands and Canada: In Search of Common PatternsGOVERNMENT AND OPPOSITION, Issue 2 2010Elke Winter In the mid-1990s, Canadian scholarship introduced an important distinction between historically incorporated national minorities and ethnic groups emerging from recent immigration. While the former may be accommodated through federal or multinational arrangements, multiculturalism has come to describe a normative framework of immigrant integration. The distinction between these analytically different types of movements is crucial for Taylor's and Kymlicka's influential theories, but the relations between different types of national and ethnic struggles for rights and recognition have remained unexplored in much of the subsequent scholarly literature. This article starts from a theoretical position where different types of diversity are viewed as highly interdependent in practice. Tracing the trajectories of multiculturalism in three different countries, the article aims to identify common patterns of how changing relations between traditionally incorporated groups affect public perceptions of and state responses to more recent immigration-induced diversity. More specifically, it asks the following question: to what extent does the absence (in Germany), discontinuation (in the Netherlands) and exacerbation (in Canada) of claims on ethnocultural grounds by traditionally incorporated groups influence the willingness of the national majority/ies to grant multicultural rights to immigrants? [source] Path-dependency and Path-creation Perspectives on Migration Trajectories: The Economic Experiences of Vietnamese Migrants in Slovakia,INTERNATIONAL MIGRATION, Issue 2 2007Vladimir Balá ABSTRACT There has been only limited research on the Vietnamese diaspora, and that has mostly focussed on Western market economies. This paper explores the distinctive migration, dictated by Cold War geopolitics, from Viet Nam to the Eastern bloc countries. It examines how the intersection of migration policies and politico-economic conditions, before and after the end of state socialism in 1989, produced two distinctive migration phases. Faced with economic constraints, and mediated by their relationships with the Slovak population, most Vietnamese who stayed in, or migrated to, Slovakia after 1989 survived economically by finding a niche in market trading. This paper adopts a path-creating path-dependent perspective to examine these migration trajectories through an analysis based on in-depth interviews with Vietnamese migrants. La diaspora vietnamienne n'a pas suscité une abondante recherche, et les enquêtes dont elle a fait l'objet ont surtout été réalisées au sein du monde occidental. La présente étude explore le caractère distinctif, dicté par lagéopolitique de la guerre froide, ayant caractérisé les flux de migration entre le Vietnam et les pays du bloc de l'Est. Elle examine comment le recoupement des politiques migratoires et des conditions politico-économiques, avant et après la fin du socialisme d'Etat en 1989, ont produit deux phases migratoires distinctes. Confrontés aux contraintes économiques, et guidés par les relations entretenues par leur pays d'origine avec la population slovaque, la plupart des Vietnamiens ayant séjourné ou immigré en Slovaquie après 1989 ont survécu, économiquement parlant, en se créant une niche commerciale. Cette étude examine ces trajectoires migratoires sous l'angle de la démarche d'autonomie créative et du choix de la dépendance en procédant à une analyse réalisée à partir d'entretiens approfondis avec des migrants vietnamiens. Poco se sabe sobre la diáspora vietnamita puesto que los estudios realizados se han centrado mayormente en las economías de mercado occidentales. En este artículo se examina la migración diferenciada, proveniente de Viet Nam hacia los países del bloque del Este, dictaminada por la geopolítica de la Guerra Fría. Además, se analiza cómo la intersección de las políticas y de las condiciones político-económicas, durante el régimen socialista y después de 1989, dieron lugar a dos etapas migratorias bien diferenciadas. Habida cuenta de las restricciones económicas y de sus relaciones con la población eslovaca, la mayoría de los vietnamitas que permanecieron o emigraron a Eslovaquia después de 1989 tuvieron que hacerse un hueco en el mercado comercial para poder sobrevivir. Por tanto, en este artículo se adopta una perspectiva de cara a la creatividad o a la dependencia a fin de examinar las trayectorias migratorias, efectuando un análisis basado en extensas entrevistas con los inmigrantes vietnamitas. [source] Stories of Rural Accumulation in Africa: Trajectories and Transitions among Rural Capitalists in SenegalJOURNAL OF AGRARIAN CHANGE, Issue 4 2007CARLOS OYA This paper analyzes primary qualitative evidence from life histories of rural capitalists in contemporary Senegal. Various common themes in the declining literature on rural capitalism in Africa are discussed with reference to the specific individual trajectories of rural farm capitalists in Senegal. The themes include the emergence of rural capitalism in the context of protracted, uneven and gradual rural social differentiation and the various processes that have accompanied it; the condition of ,entrepreneurship' in such changing historical contexts; the symbiotic relationship between different spaces (loci) of accumulation, especially trade, transport and farming and the historical context in which they take place; the crucial but sometimes contradictory role of the state in spurring or constraining rural capitalist accumulation; and the variety of ,idioms of accumulation', which reflect transitions and synthesis between non-capitalist and capitalist forms of labour surplus appropriation at the level of individual capitalists, despite some uniformity in the general logic of capital and the spread of capitalist relations of production and exchange. The paper also discusses the methodological power and limitations of oral narratives as a method to gather evidence on long-term processes of agrarian change and accumulation in rural Africa. Finally, the life histories shed some light on the origins of rural capitalists and show that there is a combination of instances of ,capitalism from above' and ,from below' but that no dominant pattern can be clearly discerned at least in the space of one or two generations. [source] Functional Trajectories in Older Persons Admitted to a Nursing Home with Disability After an Acute HospitalizationJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2009Thomas M. Gill MD OBJECTIVES: To characterize the functional trajectories of older persons admitted to a nursing home with disability after an acute hospitalization. DESIGN: Prospective cohort study of 754 community-living persons aged 70 and older who were initially nondisabled in four essential activities of daily living (ADLs). SETTING: Greater New Haven, Connecticut. PARTICIPANTS: The analytical sample included 296 participants who were newly admitted to a nursing home with disability after an acute hospitalization. MEASUREMENTS: Information on nursing home admissions, hospitalizations, and disability in essential ADLs was ascertained during monthly telephone interviews for up to 9 years. Disability was defined as the need for personal assistance in bathing, dressing, walking inside one's home, or transferring from a chair. RESULTS: The median time to the first nursing home admission with disability after an acute hospitalization was 46 months (interquartile range 27.5,75.5), and the mean number±standard deviation of ADLs that participants were disabled in upon admission was 3.0±1.2. In the month preceding hospitalization, 189 (63.9%) participants had no disability. The most common functional trajectory was discharged home with disability (46.3%), followed by continuous disability in the nursing home (27.4%), discharged home without disability (21.6%), and noncontinuous disability in the nursing home (4.4%). Only 96 (32.4%) participants returned home at (or above) their premorbid level of function. CONCLUSION: The functional trajectories of older persons admitted to a nursing home with disability after an acute hospitalization are generally poor. Additional research is needed to identify the factors responsible for these poor outcomes. [source] Memory Complaint Is Not Necessary for Diagnosis of Mild Cognitive Impairment and Does Not Predict 10-Year Trajectories of Functional Disability, Word Recall, or Short Portable Mental Status Questionnaire LimitationsJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2006Jama L. Purser PhD OBJECTIVES: To evaluate the prevalence and utility of memory complaint in a geographically representative cohort and, in cases with mild cognitive impairment (MCI), to determine whether memory complaint alters 10-year trajectories of disability in activities of daily living (ADLs), Short Portable Mental Status Questionnaire (SPMSQ) score, and 20-item word recall. DESIGN: Prospective cohort study. SETTING: Washington and Iowa counties, Iowa. PARTICIPANTS: Iowa Established Populations for Epidemiologic Studies of the Elderly (N=3,673; aged ,65; 61.3% female; 99.9% white). MEASUREMENTS: Age, sex, education, SPMSQ score, 20-item word recall, ADL or instrumental ADL disability, and chronic medical conditions. RESULTS: The prevalence of memory complaint was 34%. Although proportionally more cognitively impaired individuals were in the memory complaint group (34% vs 27%), the pattern of subclassification into cognitively intact and MCI Stage 1 and 2 subgroups was similar for people with and without memory complaint. Median SPMSQ score and number of words recalled at baseline were comparable across memory complaint categories in each subgroup. MCI participants without subjective memory complaint constituted a larger proportion of the overall sample than individuals with subjective memory complaint (460 (14%) vs 295 (8.9%)) and of persons objectively classified as having MCI (61% vs 39%). The distribution of individual 10-year change in ADL disability, SPMSQ score, and word recall were similar for those with and without memory complaint across all subgroups of cognitive impairment. CONCLUSION: Memory complaint is not necessary for MCI diagnosis and does not distinguish cases with different progression rates in disability or cognitive impairment. 2006. [source] Cognitive, Linguistic and Adaptive Functioning in Williams Syndrome: Trajectories from Early to Middle AdulthoodJOURNAL OF APPLIED RESEARCH IN INTELLECTUAL DISABILITIES, Issue 4 2010Patricia Howlin Background, Little is known about trajectories of cognitive functioning as individuals with Williams syndrome (WS) move though adulthood. Method, The present study investigated cognitive, linguistic and adaptive functioning in adults with WS aged 19,55 years, using both cross-sectional and longitudinal approaches. Results, Data from the cross-sectional study (n = 92; mean age = 32 years) indicated that IQ was comparable across age groups (Full-Scale IQ mean = 56,57) with Verbal IQ being slightly higher than Performance IQ. Daily Living Skills (as measured by the Vineland Adaptive Behavior Scales) were significantly higher in older individuals. Language abilities showed no consistent age-related differences. On formal tests of language, comprehension scores were higher than expressive language scores for almost all individuals, although this pattern was not replicated on the Vineland. In the longitudinal study, a follow-up of 47 individuals (mean age = 37 years) first assessed 12 years previously, similar trajectories were found. IQ remained very stable (FSIQ = 61,62 at both time points); there were significant improvements on the Social and Daily Living domains of the Vineland and significant decreases in Maladaptive scores. There were no improvements in language over time. Conclusions, The data indicate that adults with WS (at least up to the age of 50 years) show no evidence of deterioration in cognitive skills. Adaptive abilities continue to develop although language shows relatively little improvement with time. [source] Continuity and change in social and physical aggression from middle childhood through early adolescenceAGGRESSIVE BEHAVIOR, Issue 5 2009Marion K. Underwood For a sample followed from age 9,13 (N=281), this investigation examined developmental trajectories for social and physical aggression as measured by teacher ratings. Trajectories for both forms of aggression were estimated first separately, then jointly. Mean levels of both social and physical aggression decreased over time for the overall sample, but with high variability of individual trajectories. Subgroups followed high trajectories for both social and physical aggression. Joint estimation yielded six trajectories: low stable, low increasers, medium increasers, medium desisters, high desisters, and high increasers. Membership in the high increaser group was predicted by male gender, unmarried parents, African American ethnicity, and maternal authoritarian and permissive parenting. Permissive parenting also predicted membership in the medium increaser group. This is one of the first studies to examine social aggression longitudinally across this developmental period. Though the results challenge the claim that social aggression is at its peak in early adolescence, the findings emphasize the importance of considering different developmental trajectories in trying to understand origins and outcomes of aggression. Aggr. Behav. 35:357,375, 2009. © 2009 Wiley-Liss, Inc. [source] Trajectories and predictors of indirect aggression: results from a nationally representative longitudinal study of Canadian children aged 2,10AGGRESSIVE BEHAVIOR, Issue 4 2007Tracy Vaillancourt Abstract The purposes of this study were to model the development of indirect aggression among a nationally representative sample of 1,401 Canadian children aged 4 at T2, 6 at T3, 8 at T4 and 10 at T5, and to examine predictors of trajectory group membership from T1 (age 2) child, familial, and parenting variables. Using a semi-parametric group-based modeling approach, two distinct trajectories were identified: "increasing users" comprising of 35% of the sample and "stable low users" comprising of 65% of the sample. Using logistic regression analyses to distinguish these two groups, we found that for girls, more frequent, increasing use of indirect aggression was associated with prior prosocial and physically aggressive behavior, low SES and low parental social support at age 2. For boys, increasing use of indirect aggression was associated with prior parenting issues at age 2,inconsistency and less positive parent,child interactions. Although this study provides unique information regarding the early development of indirect aggression and its predictors, more longitudinal research is needed to fully understand its development. Aggr. Behav. 33:314,326, 2007. © 2007 Wiley-Liss, Inc. [source] Effects of Spouse Support and Hostility on Trajectories of Czech Couples' Marital Satisfaction and InstabilityJOURNAL OF MARRIAGE AND FAMILY, Issue 4 2001Frederick O. Lorenz This article examines differences in the role of spouses' hostile and supportive behaviors in predicting level and change in marital satisfaction and marital instability. We propose 2 competing hypotheses. The first hypothesis proposes that hostility is relatively volatile and support is relatively stable, and that change in hostility affects change in marital outcomes over the course of the study, whereas the overall level of support functions to maintain the level of marital outcomes. The second hypothesis argues that change in marital satisfaction is a function of change in support, whereas change in marital instability is a function of change in hostility. We tested the hypotheses by fitting growth curves to 3 waves of panel data collected from 436 Czech couples between 1994 and 1996. The results offer some support for the first hypothesis. However, the dominant pattern was for level and change in spouses' reports of their hostility to affect both wives' and husbands' level and change in marital instability, respectively, and for the level and change in husbands' reports of their support to predict level and change in wives' marital satisfaction. Other variables suggested by previous research in the United States and by the Czech transition to a market economy are examined. [source] Childhood Personality Predicts Long-Term Trajectories of Shyness and Aggressiveness in the Context of Demographic Transitions in Emerging AdulthoodJOURNAL OF PERSONALITY, Issue 1 2008Jaap J. A. Dennissen ABSTRACT In a 19-year longitudinal study, childhood personality characteristics (assessed by teachers at ages 4 to 6) were significantly related to both initial levels and changes in parental judgments of shyness and aggressiveness. Long-term stability was demonstrated by the fact that overcontrollers had consistently higher scores in shyness and undercontrollers in aggressiveness. However, undercontrollers' shyness and overcontrollers' aggressiveness changed over time from a low to a high level. Also, both types assumed adult social roles, such as leaving the parental home, establishing a first romantic relationship, and getting a part-time job, at a later time than the resilient participants. A mediation analysis indicated that under- and overcontrollers' increasing aggressiveness between age 17 and 23 was due to their longer latency of getting a part-time job. Together, results demonstrate the importance of considering person-environment transactions in explaining both change and stability in personality between childhood and adulthood. [source] Developmental Trajectories of Impulsivity and Their Association With Alcohol Use and Related Outcomes During Emerging and Young Adulthood IALCOHOLISM, Issue 8 2010Andrew K. Littlefield Background:, Research has documented normative patterns of personality change during emerging and young adulthood that reflect decreases in traits associated with substance use, such as impulsivity. However, evidence suggests variability in these developmental changes. Methods:, This study examined trajectories of impulsivity and their association with substance use and related problems from ages 18 to 35. Analyses were based on data collected from a cohort of college students (N = 489), at high and low risk for AUDs, first assessed as freshmen at a large, public university. Results:, Mixture modeling identified five trajectory groups that differed in baseline levels of impulsivity and developmental patterns of change. Notably, the trajectory group that exhibited the sharpest declines in impulsivity tended to display accelerated decreases in alcohol involvement from ages 18 to 25 compared to the other impulsivity groups. Conclusion:, Findings highlight the developmental nature of impulsivity across emerging and young adulthood and provide an empirical framework to identify key covariates of individual changes of impulsivity. [source] Longitudinal Trajectories of Ethnic Identity During the College YearsJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 4 2009Moin Syed The goals of this study were to examine trajectories of change in ethnic identity during the college years and to explore group-level and individual-level variations. Participants were 175 diverse college students who completed indices of ethnic identity exploration and commitment, self-esteem, and domain-general identity resolution. Multilevel modeling analyses indicated that exploration and commitment continued to increase during the college years. Although there were ethnic differences in initial levels of ethnic identity, the rate of change did not vary by ethnicity. Domain-general identity was positively associated with exploration and commitment and mediated the association between self-esteem and commitment. The findings highlight the ongoing development of ethnic identity beyond adolescence and suggest that ethnic identity is part of the larger identity project. [source] Trajectories of Prosocial Behavior and Physical Aggression in Middle Childhood: Links to Adolescent School Dropout and Physical ViolenceJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 3 2006Katja Kokko Trajectories of prosocial behavior and physical aggression between 6 and 12 years of age were identified for a sample (N=1,025) of males. The trajectories were then used to predict school dropout and physical violence at age 17. Using a group-based semi-parametric method, two trajectories of prosociality (low and moderate declining) and three trajectories of physical aggression (low, moderate, and high declining) were obtained. Only a small minority (3.4%) of the boys were characterized by both high aggression and moderate prosociality. Physical aggression predicted both school dropout and physical violence, but contrary to expectations, prosocial behavior did not have additive or protective effects. [source] Coping Trajectories from Adolescence to Young Adulthood: Links to Attachment State of MindJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 4 2005Inge Seiffge-Krenke The objective of this study was to examine the links between coping and attachment. In a longitudinal study of 112 participants, coping behavior was assessed at five points in time during adolescence (starting at the age of 14 years) and early adulthood. In addition, at the age of 21 years, state of mind regarding current and earlier attachment experiences was assessed by employing the Adult Attachment Interview (AAI). In both adolescence and early adulthood, differences in coping styles were found to be related to differences in attachment. Individuals classified as secure dealt with their problems more actively by using their social network during adolescence and at the age of 21 years. Both secure and dismissing individuals used more internal coping than those with a preoccupied state of mind. Latent growth curve modeling revealed that differences in active and internal coping between secure and insecure individuals applied to the rate of change in these coping styles between 14 and 21 years, with participants in the secure group showing much steeper growth in both coping styles. Only minor differences were found with respect to withdrawal as a coping style. The results represent first evidence that coping trajectories during adolescence and young adulthood are linked with attachment state of mind. [source] School Engagement Trajectories and Their Differential Predictive Relations to DropoutJOURNAL OF SOCIAL ISSUES, Issue 1 2008Michel Janosz Although most theories draw upon the construct of school engagement in their conceptualization of the dropout process, research addressing its hypothesized prospective relation with dropout remains scarce and does not account for the academic and social heterogeneity of students who leave school prematurely. This study explores the reality of different life-course pathways of school engagement and their predictive relations to dropout. Using an accelerated longitudinal design, we used growth mixture modeling to generate seven distinct trajectories of school engagement with 12- to 16-year-old students (N = 13,300). A vast majority of students were classified into three stable trajectories, distinguishing themselves at moderate to very high levels of school engagement. We refer to these as developmentally normative pathways in light of their frequent occurrence and stability. Although regrouping only one-tenth of participants, four other nonnormative (or unexpected pathways) accounted for the vast majority of dropouts. Dropout risk was closely linked with unstable pathways of school engagement. We conclude by debating the delicate investment balance between universal strategies and more selective and differentiated strategies to prevent dropout. We also discuss the need to better understand why, within normative trajectories, some students with high levels of school engagement drop out of school. [source] Heterogeneity in the course of posttraumatic stress disorder: Trajectories of symptomatology,JOURNAL OF TRAUMATIC STRESS, Issue 3 2010Benjamin D. Dickstein Unconditional and conditional trajectories of posttraumatic stress disorder (PTSD) symptomatology were examined using a sample of U.S. soldiers deployed on a NATO-led peacekeeping mission to Kosovo. Data were collected at 4 time points, ranging from the weeks leading up to deployment to 9-months postdeployment. Latent class growth analysis revealed 4 unique symptom trajectories: resilience, recovery, delayed, and unrealized anxiety. Variables identified as significant predictors of trajectory class included previous traumatic events, combat exposure, peacekeeping daily hassles, depression, alcohol use, aggressive behavior, stress reactivity, and military rank. Results from this study add to the literature detailing the variability in PTSD course, as well as to the literature pertaining to predictors of PTSD onset and course. [source] From Militancy to Clientelism: Labor Union Strategies and Membership Trajectories in Contemporary ChileLATIN AMERICAN POLITICS AND SOCIETY, Issue 2 2010Indira Palacios-Valladares ABSTRACT For the past 30 years, Chilean unionism has been shrinking. Through a comparison of the membership trajectories of 26 unions in two firms between 1990 and 2004, this article explains why some unions defied this trend and how their success affected overall union density in their firms. It argues that the unions that experienced the most favorable membership outcomes were those that, at key junctures of firm restructuring, earliest or most aggressively established a partnership relationship with management. However, in a context of great labor weakness, these cases of union accommodation took the form of exclusive patron-client exchanges, which exacerbated collective action problems and further eroded union density. [source] Trajectories Toward Peace: Mediator Sequencing Strategies in Intractable Communal ConflictsNEGOTIATION JOURNAL, Issue 2 2003Joshua N. Weiss The author identifies three distinct mediation sequencing strategies used in intratable communal conflicts: the graualism model; a "boulder-in-the-road" approach; and the "committee" strategy. Using case examples of contemporary mediation efforts, he describes the three approaches and their advantages and disadvantages. A wider-angle approach to the differences in how mediators and conflicting parties achieve peace in these destructive conflicts is useful for both scholarly inquiry and practice. [source] Occupational Trajectories of Legal US Immigrants: Downgrading and RecoveryPOPULATION AND DEVELOPMENT REVIEW, Issue 3 2008Ilana Redstone Akresh Data from the New Immigrant Survey 2003 are examined to analyze trajectories in occupational prestige between the last job abroad and the first US job and from the first US job to the current US job for a select sample of men and women. Incorporating the first job in the United States overcomes an important limitation faced by many previous studies that were generally restricted to a comparison of the last job abroad and the US job as measured at the time of the survey. Distinctions are made between class-of-admission groups, since the trajectories toward labor market success vary systematically along that dimension. Consistent with a model of immigrant occupational assimilation, all preference groups show a U-shaped adjustment pattern with, on average, initial downgrading followed by subsequent ascension. However, although all groups exhibit a similar pattern, the trough of the U is deepest for refugees, who also experience the steepest subsequent upward climb. [source] Trajectories in the Development of Islamic Theological Thought: the Synthesis of Kal,mRELIGION COMPASS (ELECTRONIC), Issue 4 2007Mustafa Shah The field of Islamic theology (kal,m) is not merely a receptacle for the presentation of the creedal statements and doctrinal catechisms of Islam; it derives its raison d'être not only from the articulation and elucidation of the doctrines of faith, but also by means of its rational and painstaking explication of dogma. While many of the dogmatic statements expressed in Islamic theology naturally emanate from a traditional substratum, countless more are the result of dialectical discussions as theologians expounded upon abstract constructs of religious dogma. Recent academic research is exploring the history, trends and conceptual achievements behind the Islamic experiment with theology, providing insights into the tradition's ability to integrate, refine and expand theological constructs. Scholars are also concerned with issues such as origins, authenticity and ascription, although such matters are not deflecting attention from the rich stock of resources and materials kal,m has to offer. [source] Trajectories of fatigue in family caregivers of patients undergoing radiation therapy for prostate cancer,RESEARCH IN NURSING & HEALTH, Issue 2 2009Barbara A. Swore Fletcher Abstract Predictors of and trajectories for evening and morning fatigue were evaluated in family caregivers of oncology patients using hierarchical linear modeling. Evening fatigue trajectory fit a quadratic model. Predictors included baseline sleep disturbances in family caregivers and baseline evening fatigue in patients. Morning fatigue trajectory fit a linear model. Predictors were baseline trait anxiety, levels of perceived family support, and baseline morning fatigue in patients. Findings suggest considerable inter-individual variability in the trajectories of evening and morning fatigue. Evaluating family caregivers for sleep disturbance, anxiety, and poor family support, as well as high levels of patient fatigue, could identify those family caregivers at highest risk for sustained fatigue trajectories. © 2008 Wiley Periodicals, Inc. Res Nurs Health 32:125,139, 2009 [source] Sampling Techniques Influence Understory Plant Trajectories After Restoration: An Example from Ponderosa Pine RestorationRESTORATION ECOLOGY, Issue 4 2003Julie E. Korb Abstract Although there is no one correct technique for sampling vegetation, the sampling design chosen may greatly influence the conclusions researchers can draw from restoration treatments. Considerations when designing vegetation sampling protocol include determining what sampling attributes to measure, the size and shape of the sampling plot, the number of replicates and their location within the study area, and the frequency of sampling. We installed 20 point-intercept transects (50-m long), 8 belt transects (10 × 50 m), 10 adapted Daubenmire transects (four 0.5 × 2-m plots), and 4 modified-Whittaker plots (20 × 50 m with smaller nested plots) in treatment and control units to measure understory herbaceous response in a forest restoration experiment that tested different treatments. Point-intercept transects on average recorded at least twice as much plant cover as did adapted Daubenmire transects and modified-Whittaker plots taken at the same location for all control and treatment units. Point-intercept transects and adapted Daubenmire plots on average captured fewer rare and exotic species in the control and treatment units in comparison with the belt transects and modified-Whittaker plots. Modified-Whittaker plots captured the highest species richness in all units. Early successional understory response to restoration treatments was likely masked by the response of the herbaceous community to yearly climatic variation (dry vs. wet years). Species richness and abundance were higher in wet years than dry years for all control and treatment units. Our results illustrate that sampling techniques can greatly influence perceptions of understory plant trajectories and therefore the interpretation of whether restoration goals have been achieved. In addition, our results suggest that restoration monitoring needs to be conducted for a sufficient length of time so that restoration treatment responses can be detected. [source] Personality Risk Factors Associated with Trajectories of Tobacco UseTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 6 2006Judith S. Brook EdD The purpose of this longitudinal, prospective study was to evaluate trajectories of smoking in a cohort of African-American and Puerto Rican young adults and describe personality and behavioral factors associated with specific smoking trajectory group membership. Participants consisted of African-American and Puerto Rican male and female young adults (n = 451, mean age 26) from an inner-city community. Data were collected at four time points over a period of 13 years using structured interviews. Interviews took place within the schools and the participants' homes. Scales with adequate psychometric properties were adapted from previously validated measures. Variables that were examined for this study came from the domains of internalizing behaviors, externalizing behaviors, drug use, and demographic information. Data were analyzed using latent growth mixture modeling to explore discrete smoking trajectories. Logistic regression analyses were then used to examine the risk factors associated with the various smoking trajectory groups. Four trajectory groups were determined to best fit the data: nonsmokers, maturing-out smokers, late-starting smokers, and early-starting continuous smokers. Subjects who were unconventional, experienced intrapersonal distress, and used alcohol and illegal drugs were more likely to belong to one of the smoking trajectory groups than to the nonsmoking group. The early-starting continuous group scored highest on these personal risk attributes. The long-term impact of unconventional behavior, intrapersonal distress, and drug use on developmental trajectories of smoking support the importance of early intervention and prevention. [source] Trajectories of Alcohol Consumption Following Liver TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 10 2010A. DiMartini Any use of alcohol in the years following liver transplantation (LTX) approaches 50% of patients transplanted for alcoholic liver disease (ALD). We collected detailed prospective data on alcohol consumption following LTX for ALD to investigate ongoing patterns of use. Using trajectory modeling we identified four distinct alcohol use trajectories. One group had minimal use over time. Two other groups developed early onset moderate-to-heavy consumption and one group developed late onset moderate use. These trajectories demonstrate that alcohol use varies based on timing of onset, quantity and duration. Using discriminant function analysis, we examine characteristics of recipient's pre-LTX alcohol histories and early post-LTX psychological stressors to identify the profile of those at risk for these specific trajectories. We discuss the relevance of these findings to clinical care and preliminarily to outcomes. [source] | ||||||||||||||||||||||||||||||||||||||||