Longitudinal plasma metanephrines preceding pheochromocytoma diagnosis: a retrospective case-control serum repository study.

PubMed

Olson, S W; Yoon, S; Baker, T; Prince, L K; Oliver, D; Abbott, K C

2016-03-01

Plasma metanephrines (PMN) are highly sensitive for diagnosis of pheochromocytoma, but the natural history of PMN before pheochromocytoma diagnosis has not been previously described. The aim of the study was to compare the progression of PMN before pheochromocytoma diagnosis to matched healthy and essential hypertension disease controls. A retrospective case-control Department of Defense Serum Repository (DoDSR) study. We performed a DoDSR study that compared three longitudinal pre-diagnostic PMN for 30 biopsy-proven pheochromocytoma cases to three longitudinal PMN for age, sex, race, and age of serum sample matched healthy and essential hypertension disease controls. Predominant metanephrine (MN) or normetanephrine (NMN) production was identified for each case and converted to a percentage of the upper limit of normal to allow analysis of all cases together. PMN were measured by Quest Diagnostics. The predominant plasma metanephrine (PPM) was >100 and 300% of the upper limit of normal a median of 6.6 and 4.1 years before diagnosis respectively. A greater percentage of pheochromocytoma patients had a PPM >100 and >300% of the upper limit of normal compared with combined healthy and essential hypertension disease controls <2, 2-8, and >8 years prior to diagnosis. For patients with a baseline PPM 90-300% of the upper limit of normal, a 25% rate of rise per year was 100% specific for pheochromocytoma. PPMs elevate years before diagnosis which suggests that delayed diagnoses are common. For mild PMN elevations, follow-up longitudinal PMN trends may provide a highly specific and economical diagnostic tool. © 2016 European Society of Endocrinology.

The Pre-Incubator: A Longitudinal Study of 10 Years of University Pre-Incubation in Wales

ERIC Educational Resources Information Center

Voisey, Pamela; Jones, Paul; Thomas, Brychan

2013-01-01

This paper describes a longitudinal study of over 10 years of university pre-incubation in Wales, using case studies of incubated businesses to track their performance since 2001. Surviving "graduated" businesses were investigated and quantitative and qualitative data were gathered to profile the current status of these businesses and…

Gifted Girls and Nonmathematical Aspirations: A Longitudinal Case Study of Two Gifted Korean Girls

ERIC Educational Resources Information Center

Lee, Kyeong Hwa; Sriraman, Bharath

2012-01-01

In this longitudinal study of two gifted Korean girls, experiences with early admittance into a gifted program are charted alongside their family and societal experiences that ultimately influenced their career choices in nonmathematical fields. The 8-year-long qualitative study involved extensive interviews with the two gifted girls and their…

Variability in Fundamental Frequency during Speech in Prodromal and Incipient Parkinson's Disease: A Longitudinal Case Study

ERIC Educational Resources Information Center

Harel, Brian; Cannizzaro, Michael; Snyder, Peter J.

2004-01-01

Nearly two centuries ago, Parkinson (1817) first observed that a particular pattern of speech changes occur in patients with idiopathic Parkinson's disease (PD). Numerous studies have documented these changes using a wide variety of acoustic measures, and yet few studies have attempted to quantify any such changes longitudinally, through the early…

From ICT Coordination to ICT Integration: A Longitudinal Case Study

ERIC Educational Resources Information Center

Tondeur, J.; Cooper, M.; Newhouse, C. P.

2010-01-01

This study utilizes a school-improvement perspective to examine the role of curriculum coordination in the integration of information and communication technologies (ICT) into primary schools. The nature and impact of this role is examined in seven primary schools in Australia. These seven schools were drawn from a longitudinal intervention that…

"A Writer More than . . . A Child": A Longitudinal Study Examining Adolescent Writer Identity

ERIC Educational Resources Information Center

Lammers, Jayne C.; Marsh, Valerie L.

2018-01-01

This article reconsiders theoretical claims of identity fluidity, stability, and agency through a longitudinal case study investigating one adolescent's writing over time and across spaces. Qualitative data spanning her four years of high school were collected and analyzed using a grounded theory approach with literacy-and-identity theory…

Joint models for longitudinal and time-to-event data: a review of reporting quality with a view to meta-analysis.

PubMed

Sudell, Maria; Kolamunnage-Dona, Ruwanthi; Tudur-Smith, Catrin

2016-12-05

Joint models for longitudinal and time-to-event data are commonly used to simultaneously analyse correlated data in single study cases. Synthesis of evidence from multiple studies using meta-analysis is a natural next step but its feasibility depends heavily on the standard of reporting of joint models in the medical literature. During this review we aim to assess the current standard of reporting of joint models applied in the literature, and to determine whether current reporting standards would allow or hinder future aggregate data meta-analyses of model results. We undertook a literature review of non-methodological studies that involved joint modelling of longitudinal and time-to-event medical data. Study characteristics were extracted and an assessment of whether separate meta-analyses for longitudinal, time-to-event and association parameters were possible was made. The 65 studies identified used a wide range of joint modelling methods in a selection of software. Identified studies concerned a variety of disease areas. The majority of studies reported adequate information to conduct a meta-analysis (67.7% for longitudinal parameter aggregate data meta-analysis, 69.2% for time-to-event parameter aggregate data meta-analysis, 76.9% for association parameter aggregate data meta-analysis). In some cases model structure was difficult to ascertain from the published reports. Whilst extraction of sufficient information to permit meta-analyses was possible in a majority of cases, the standard of reporting of joint models should be maintained and improved. Recommendations for future practice include clear statement of model structure, of values of estimated parameters, of software used and of statistical methods applied.

Longitudinal association of hemostatic factors with risk for cancers of the breast, colorectum, and lung among postmenopausal women.

PubMed

Kabat, Geoffrey C; Salazar, Christian R; Zaslavsky, Oleg; Lane, Dorothy S; Rohan, Thomas E

2016-09-01

The aim of this study was to examine whether hemostatic factors associated with coagulation and inflammation pathways are associated with cancer risk in postmenopausal women. We used data from the Women's Health Initiative study to examine the association of plasma fibrinogen levels, factor VII antigen activity, and factor VII concentration measured at baseline and during follow-up with the risk for cancers of the breast, colorectum, and lung. Among 5287 women who were followed up for a median of 11.4 years, 275 cases of breast cancer, 102 cases of colorectal cancer, and 90 cases of lung cancer were identified. Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals for the association of hemostatic factors with each cancer. Hemostatic factors were not associated with breast cancer in either baseline or longitudinal analyses. Baseline hemostatic factors showed weak associations with colorectal cancer; however, no association was seen in longitudinal analyses. Fibrinogen was positively associated with lung cancer in both baseline and longitudinal analyses; the association was seen only in never and former smokers, not in current smokers. We found no evidence of an association between hemostatic factors and breast or colorectal cancer in postmenopausal women. The positive association of fibrinogen levels with lung cancer requires confirmation in larger studies.

A Longitudinal Study of Environmental and Outdoor Education: A Cultural Change

ERIC Educational Resources Information Center

Tal, Tali; Morag, Orly

2013-01-01

In this case-study, we present a longitudinal study of one elementary (grades 1-6) school's environmental education (EE) in order to understand the ways in which the school culture supports outdoor EE as a critical component of their science education program. The school, which was known for its school-based EE curriculum that encompasses an…

A Longitudinal Study of Post-School Provision for Irish School-Leavers with Intellectual Disability

ERIC Educational Resources Information Center

McConkey, Roy; Kelly, Fionnola; Craig, Sarah; Keogh, Fiona

2017-01-01

Background: In recent years, efforts have been made to improve the transition of pupils with intellectual disabilities to adult services and to offer a wider range of choices. However, there have been few longitudinal studies to monitor the services provided to young adults post-school. This case study in the Republic of Ireland identified the…

Students' Understanding of the Nature of Matter and Chemical Reactions--A Longitudinal Study of Conceptual Restructuring

ERIC Educational Resources Information Center

Øyehaug, Anne Bergliot; Holt, Anne

2013-01-01

This longitudinal study aims to provide greater insight into how students' understanding of matter and chemical reactions develops over time and how their knowledge structures are restructured. Four case-study students in a Norwegian primary school were followed for two years from age 10-11 to age 12-13. Researchers were responsible for…

Results of endocapsular phacofracture debulking of hard cataracts

PubMed Central

Davison, James A

2015-01-01

Purpose/aim of the study To present a phacoemulsification technique for hard cataracts and compare postoperative results using two different ultrasonic tip motions during quadrant removal. Materials and methods A phacoemulsification technique which employs in situ fracture and endocapsular debulking for hard cataracts is presented. The prospective study included 56 consecutive cases of hard cataract (LOCS III NC [Lens Opacification Classification System III, nuclear color], average 4.26), which were operated using the Infiniti machine and the Partial Kelman tip. Longitudinal tip movement was used for sculpting for all cases which were randomized to receive longitudinal or torsional/interjected longitudinal (Intelligent Phaco [IP]) strategies for quadrant removal. Measurements included cumulative dissipated energy (CDE), 3 months postoperative surgically induced astigmatism (SIA), and corneal endothelial cell density (ECD) losses. Results No complications were recorded in any of the cases. Respective overall and longitudinal vs IP means were as follows: CDE, 51.6±15.6 and 55.7±15.5 vs 48.6±15.1; SIA, 0.36±0.2 D and 0.4±0.2 D vs 0.3±0.2 D; and mean ECD loss, 4.1%±10.8% and 5.9%±13.4% vs 2.7%±7.8%. The differences between longitudinal and IP were not significant for any of the three categories. Conclusion The endocapsular phacofracture debulking technique is safe and effective for phacoemulsification of hard cataracts using longitudinal or torsional IP strategies for quadrant removal with the Infiniti machine and Partial Kelman tip. PMID:26203213

Tailored Panel Management: A Theory-Based Approach to Building and Maintaining Participant Commitment to a Longitudinal Study.

PubMed

Estrada, Mica; Woodcock, Anna; Schultz, P Wesley

2014-02-01

Many psychological processes unfold over time, necessitating longitudinal research designs. Longitudinal research poses a host of methodological challenges, foremost of which is participant attrition. Building on Dillman's work, we provide a review of how social influence and relationship research informs retention strategies in longitudinal studies. Objective: We introduce the tailored panel management (TPM) approach, which is designed to establish communal norms that increase commitment to a longitudinal study, and this commitment, in turn, increases response rates and buffers against attrition. Specifically, we discuss practices regarding compensation, communication, consistency, and credibility that increase longer term commitment to panel participation. Research design: Throughout the article, we describe how TPM is being used in a national longitudinal study of undergraduate minority science students. TheScienceStudy is a continuing panel, which has 12 waves of data collected across 6 academic years, with response rates ranging from 70% to 92%. Although more than 90% of participants have either left or graduated from their undergraduate degree program, this highly mobile group of people remains engaged in the study. TheScienceStudy has usable longitudinal data from 96% of the original panel. Conclusion: This article combines social psychological theory, current best practice, and a detailed case study to illustrate the TPM approach to longitudinal data collection. The approach provides guidance for other longitudinal researchers, and advocates for empirical research into longitudinal research methodologies. © The Author(s) 2014.

Longitudinal Assessment of Progress in Reasoning Capacity and Relation with Self-Estimation of Knowledge Base

ERIC Educational Resources Information Center

Collard, Anne; Mélot, France; Bourguignon, Jean-Pierre

2015-01-01

The aim of the study was to investigate progress in reasoning capacity and knowledge base appraisal in a longitudinal analysis of data from summative evaluation throughout a medical problem-based learning curriculum. The scores in multidisciplinary discussion of a clinical case and multiple choice questionnaires (MCQs) were studied longitudinally…

WISC-R Verbal and Performance IQ Discrepancy in an Unselected Cohort: Clinical Significance and Longitudinal Stability.

ERIC Educational Resources Information Center

Moffitt, Terrie E.; Silva, P. A.

1987-01-01

Examined children whose Wechsler Intelligence Scale for Children-Revised (WISC-R) verbal and performance Intelligence Quotient discrepancies placed them beyond the 90th percentile. Longitudinal study showed 23 percent of the discrepant cases to be discrepant at two or more ages. Studied frequency of perinatal difficulties, early childhood…

Predictors of the Acquisition and Portability of Transferable Skills: A Longitudinal Portuguese Case Study on Education

ERIC Educational Resources Information Center

Rocha, Magda

2015-01-01

The basis for this longitudinal study was to find the predictors of transferable skills acquisition and portability among university sophomore students. The method employed was the path analysis using as variables: (1) the theoretical framework of transferable skills representations (Evers and Rush in "Manag Learn" 27(4):275-300, 1996;…

Vowel Development in an Emergent Mandarin-English Bilingual Child: A Longitudinal Study

ERIC Educational Resources Information Center

Yang, Jing; Fox, Robert A.; Jacewicz, Ewa

2015-01-01

This longitudinal case study documents the emergence of bilingualism in a young monolingual Mandarin boy on the basis of an acoustic analysis of his vowel productions recorded via a picture-naming task over 20 months following his enrollment in an all-English (L2) preschool at the age of 3;7. The study examined (1) his initial L2 vowel space, (2)…

A Longitudinal Study of the Educational and Career Trajectories of Female Participants of an Urban Informal Science Education Program

ERIC Educational Resources Information Center

Fadigan, Kathleen A.; Hammrich, Penny L.

2004-01-01

The purpose of this longitudinal case study is to describe the educational trajectories of a sample of 152 young women from urban, low-income, single-parent families who participated in the Women in Natural Sciences (WINS) program during high school. Utilizing data drawn from program records, surveys, and interviews, this study also attempts to…

Preservation of person-specific knowledge in semantic memory disorder: a longitudinal investigation in two cases of dementia.

PubMed

Haslam, Catherine; Sabah, Mazen

2013-03-01

The double dissociation involving person-specific and general semantic knowledge is supported by numerous patient studies, though cases with preservation of the former are few. In this paper, we report longitudinal data from two cases. Their knowledge in both domains was preserved at the start of the investigation, but progressive deterioration was primarily observed on tests of general semantics. These data strengthen the evidence-base for preservation of person-specific knowledge in semantic memory disorder, and support its separate representation from object knowledge. © 2012 The British Psychological Society.

The Effect of State Medicaid Case-Mix Payment on Nursing Home Resident Acuity

PubMed Central

Feng, Zhanlian; Grabowski, David C; Intrator, Orna; Mor, Vincent

2006-01-01

Objective To examine the relationship between Medicaid case-mix payment and nursing home resident acuity. Data Sources Longitudinal Minimum Data Set (MDS) resident assessments from 1999 to 2002 and Online Survey Certification and Reporting (OSCAR) data from 1996 to 2002, for all freestanding nursing homes in the 48 contiguous U.S. states. Study Design We used a facility fixed-effects model to examine the effect of introducing state case-mix payment on changes in nursing home case-mix acuity. Facility acuity was measured by aggregating the nursing case-mix index (NCMI) from the MDS using the Resource Utilization Group (Version III) resident classification system, separately for new admits and long-stay residents, and by an OSCAR-derived index combining a range of activity of daily living dependencies and special treatment measures. Data Collection/Extraction Methods We followed facilities over the study period to create a longitudinal data file based on the MDS and OSCAR, respectively, and linked facilities with longitudinal data on state case-mix payment policies for the same period. Principal Findings Across three acuity measures and two data sources, we found that states shifting to case-mix payment increased nursing home acuity levels over the study period. Specifically, we observed a 2.5 percent increase in the average acuity of new admits and a 1.3 to 1.4 percent increase in the acuity of long-stay residents, following the introduction of case-mix payment. Conclusions The adoption of case-mix payment increased access to care for higher acuity Medicaid residents. PMID:16899009

Case Study: Longitudinal Treatment of Adolescents with Depression and Inflammatory Bowel Disease

ERIC Educational Resources Information Center

Szigethy, Eva; Carpenter, Johanna; Baum, Emily; Kenney, Elyse; Baptista-Neto, Lourival; Beardslee, William R.; DeMaso, David Ray

2006-01-01

Objective: To assess longitudinal maintenance of improvements in depression, anxiety, global functioning, and physical health perception in 11 adolescents at 6 and 12 months following completion of manual-based cognitive-behavioral therapy. Method: Standardized instruments assessed follow-up changes in depression, anxiety, physical health, and…

Exposure enriched outcome dependent designs for longitudinal studies of gene-environment interaction.

PubMed

Sun, Zhichao; Mukherjee, Bhramar; Estes, Jason P; Vokonas, Pantel S; Park, Sung Kyun

2017-08-15

Joint effects of genetic and environmental factors have been increasingly recognized in the development of many complex human diseases. Despite the popularity of case-control and case-only designs, longitudinal cohort studies that can capture time-varying outcome and exposure information have long been recommended for gene-environment (G × E) interactions. To date, literature on sampling designs for longitudinal studies of G × E interaction is quite limited. We therefore consider designs that can prioritize a subsample of the existing cohort for retrospective genotyping on the basis of currently available outcome, exposure, and covariate data. In this work, we propose stratified sampling based on summaries of individual exposures and outcome trajectories and develop a full conditional likelihood approach for estimation that adjusts for the biased sample. We compare the performance of our proposed design and analysis with combinations of different sampling designs and estimation approaches via simulation. We observe that the full conditional likelihood provides improved estimates for the G × E interaction and joint exposure effects over uncorrected complete-case analysis, and the exposure enriched outcome trajectory dependent design outperforms other designs in terms of estimation efficiency and power for detection of the G × E interaction. We also illustrate our design and analysis using data from the Normative Aging Study, an ongoing longitudinal cohort study initiated by the Veterans Administration in 1963. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Becoming (Less) Scientific: A Longitudinal Study of Students' Identity Work from Elementary to Middle School Science

ERIC Educational Resources Information Center

Carlone, Heidi B.; Scott, Catherine M.; Lowder, Cassi

2014-01-01

Students' declining science interest in middle school is often attributed to psychological factors like shifts of motivational values, decrease in self-efficacy, or doubts about the utility of schooling in general. This paper adds to accounts of the middle school science problem through an ethnographic, longitudinal case study of three…

Developmental Trajectories in Adolescents and Adults With Autism: The Case of Daily Living Skills

ERIC Educational Resources Information Center

Smith, Leann E.; Maenner, Matthew J.; Seltzer, Marsha Mailick

2012-01-01

Objective: This study aimed to investigate the longitudinal course of daily living skills in a large, community-based sample of adolescents and adults with autism spectrum disorders (ASD) over a 10-year period. Method: Adolescents and adults with ASD (n = 397) were drawn from an ongoing, longitudinal study of individuals with ASD and their…

The effect of state medicaid case-mix payment on nursing home resident acuity.

PubMed

Feng, Zhanlian; Grabowski, David C; Intrator, Orna; Mor, Vincent

2006-08-01

To examine the relationship between Medicaid case-mix payment and nursing home resident acuity. Longitudinal Minimum Data Set (MDS) resident assessments from 1999 to 2002 and Online Survey Certification and Reporting (OSCAR) data from 1996 to 2002, for all freestanding nursing homes in the 48 contiguous U.S. states. We used a facility fixed-effects model to examine the effect of introducing state case-mix payment on changes in nursing home case-mix acuity. Facility acuity was measured by aggregating the nursing case-mix index (NCMI) from the MDS using the Resource Utilization Group (Version III) resident classification system, separately for new admits and long-stay residents, and by an OSCAR-derived index combining a range of activity of daily living dependencies and special treatment measures. We followed facilities over the study period to create a longitudinal data file based on the MDS and OSCAR, respectively, and linked facilities with longitudinal data on state case-mix payment policies for the same period. Across three acuity measures and two data sources, we found that states shifting to case-mix payment increased nursing home acuity levels over the study period. Specifically, we observed a 2.5 percent increase in the average acuity of new admits and a 1.3 to 1.4 percent increase in the acuity of long-stay residents, following the introduction of case-mix payment. The adoption of case-mix payment increased access to care for higher acuity Medicaid residents.

Cervical intradural disc herniation.

PubMed

Iwamura, Y; Onari, K; Kondo, S; Inasaka, R; Horii, H

2001-03-15

A case report of anterior en bloc resected cervical intradural disc herniation and a review of the literature. To discuss the pathogenesis of cervical intradural disc herniation. Including this study case, only 17 cases of cervical intradural disc herniation have been reported. There have been few detailed reports concerning the pathogenesis of cervical intradural disc herniation. A cervical intradural disc herniation at C6-C7, with localized hypertrophy and segmentally ossified posterior longitudinal ligament, is reported in a 45-year-old man who had Brown-Sequard syndrome diagnosed on neurologic examination. Neuroradiologic, operative, and histologic findings, particularly the pathology of the anterior en bloc resected posterior vertebral portion of C6 and C7, were evaluated for discussion of the pathogenesis. Adhesion of dura mater and hypertrophic posterior longitudinal ligament was observed around a perforated portion of the herniated disc, and histologic study showed irregularity in fiber alignment accompanied by scattered inflammatory cell infiltration and hypertrophy in the posterior longitudinal ligament. The cervical intradural disc herniation was removed successfully and followed by C5-Th1 anterior interbody fusion with fibular strut graft. Neurologic recovery was complete except for minor residual sensory disturbance in the leg 7 years after the surgery. Cervical intradural disc herniation is an extremely rare condition. The pathogenesis remains obscure. Only 16 cases have been reported in the literature, and there has been little discussion concerning the local pathology of the herniated portion. The pathogenesis of the disease in the patient reported here was considered to be the adhesion and fragility of dura mater and posterior longitudinal ligament. This was caused by hypertrophy, with chronic inflammation and ossification of the posterior longitudinal ligament sustaining chronic mechanical irritation to the dura mater, leading to perforation of the herniated disc by an accidental force.

Effort-reward imbalance and work ability: cross-sectional and longitudinal findings from the Second German Sociomedical Panel of Employees

PubMed Central

2012-01-01

Background Although data from longitudinal studies are sparse, effort-reward imbalance (ERI) seems to affect work ability. However, the potential pathway from restricted work ability to ERI must also be considered. Therefore, the aim of our study was to analyse cross-sectional and longitudinal associations between ERI and work ability and vice versa. Methods Data come from the Second German Sociomedical Panel of Employees. Logistic regression models were estimated to determine cross-sectional and longitudinal associations. The sample used to predict new cases of poor or moderate work ability was restricted to cases with good or excellent work ability at baseline. The sample used to predict new cases of ERI was restricted to persons without ERI at baseline. Results The cross-sectional analysis included 1501 full-time employed persons. The longitudinal analyses considered 600 participants with good or excellent baseline work ability and 666 participants without baseline ERI, respectively. After adjustment for socio-demographic variables, health-related behaviour and factors of the work environment, ERI was cross-sectionally associated with poor or moderate work ability (OR = 1.980; 95% CI: 1.428 to 2.747). Longitudinally, persons with ERI had 2.1 times higher odds of poor or moderate work ability after one year (OR = 2.093; 95% CI: 1.047 to 4.183). Conversely, persons with poor or moderate work ability had 2.6 times higher odds of an ERI after one year (OR = 2.573; 95% CI: 1.314 to 5.041). Conclusions Interventions that enable workers to cope with ERI or address indicators of ERI directly could promote the maintenance of work ability. Integration management programmes for persons with poor work ability should also consider their psychosocial demands. PMID:23067110

Losing a Language in Childhood: A Longitudinal Case Study on Language Attrition

ERIC Educational Resources Information Center

Flores, Cristina

2015-01-01

This paper is based upon a longitudinal study of L2 attrition in a bilingual child who grew up in an L2 migration background (Germany) and moved to the country of origin (Portugal) at the age of nine, experiencing a "dominance shift from the L2 to the L1." The study aims to analyze the effects of language loss in L2 German. Data…

Results of endocapsular phacofracture debulking of hard cataracts.

PubMed

Davison, James A

2015-01-01

To present a phacoemulsification technique for hard cataracts and compare postoperative results using two different ultrasonic tip motions during quadrant removal. A phacoemulsification technique which employs in situ fracture and endocapsular debulking for hard cataracts is presented. The prospective study included 56 consecutive cases of hard cataract (LOCS III NC [Lens Opacification Classification System III, nuclear color], average 4.26), which were operated using the Infiniti machine and the Partial Kelman tip. Longitudinal tip movement was used for sculpting for all cases which were randomized to receive longitudinal or torsional/interjected longitudinal (Intelligent Phaco [IP]) strategies for quadrant removal. Measurements included cumulative dissipated energy (CDE), 3 months postoperative surgically induced astigmatism (SIA), and corneal endothelial cell density (ECD) losses. No complications were recorded in any of the cases. Respective overall and longitudinal vs IP means were as follows: CDE, 51.6±15.6 and 55.7±15.5 vs 48.6±15.1; SIA, 0.36±0.2 D and 0.4±0.2 D vs 0.3±0.2 D; and mean ECD loss, 4.1%±10.8% and 5.9%±13.4% vs 2.7%±7.8%. The differences between longitudinal and IP were not significant for any of the three categories. The endocapsular phacofracture debulking technique is safe and effective for phacoemulsification of hard cataracts using longitudinal or torsional IP strategies for quadrant removal with the Infiniti machine and Partial Kelman tip.

A Longitudinal Analysis of Students' Motives for Communicating with Their Instructors

ERIC Educational Resources Information Center

Myers, Scott A.

2017-01-01

This study utilized the longitudinal survey research design using students' motives to communicate with their instructors as a test case. Participants were 282 undergraduate students enrolled in introductory communication courses at a large Mid-Atlantic university who completed the Student Communication Motives scale at three points (Time 1:…

South Carolina Case Study: Building a Student-Level Longitudinal Data System

ERIC Educational Resources Information Center

Kugle, Cherry; Smith, Nancy

2007-01-01

The Data Quality Campaign is a national, collaborative effort to encourage and support state policymakers to improve the collection, availability and use of high-quality education data and to implement state longitudinal data systems to improve student achievement. The campaign aims to provide tools and resources that will assist state development…

Louisiana Case Study: Building a Student-Level Longitudinal Data System

ERIC Educational Resources Information Center

Kugle, Cherry; Smith, Nancy

2008-01-01

The Data Quality Campaign is a national, collaborative effort to encourage and support state policymakers to improve the collection, availability and use of high-quality education data and to implement state longitudinal data systems to improve student achievement. The campaign aims to provide tools and resources that will assist state development…

Longitudinal Examination of Optimism, Personal Self-Efficacy and Student Well-Being: A Path Analysis

ERIC Educational Resources Information Center

Phan, Huy P.

2016-01-01

The present longitudinal study, based on existing theoretical tenets, explored a conceptual model that depicted four major orientations: optimism, self-efficacy, and academic well-being. An important question for consideration, in this case, involved the testing of different untested trajectories that could explain and predict individuals'…

MODELING LEFT-TRUNCATED AND RIGHT-CENSORED SURVIVAL DATA WITH LONGITUDINAL COVARIATES

PubMed Central

Su, Yu-Ru; Wang, Jane-Ling

2018-01-01

There is a surge in medical follow-up studies that include longitudinal covariates in the modeling of survival data. So far, the focus has been largely on right censored survival data. We consider survival data that are subject to both left truncation and right censoring. Left truncation is well known to produce biased sample. The sampling bias issue has been resolved in the literature for the case which involves baseline or time-varying covariates that are observable. The problem remains open however for the important case where longitudinal covariates are present in survival models. A joint likelihood approach has been shown in the literature to provide an effective way to overcome those difficulties for right censored data, but this approach faces substantial additional challenges in the presence of left truncation. Here we thus propose an alternative likelihood to overcome these difficulties and show that the regression coefficient in the survival component can be estimated unbiasedly and efficiently. Issues about the bias for the longitudinal component are discussed. The new approach is illustrated numerically through simulations and data from a multi-center AIDS cohort study. PMID:29479122

Mental and Motor Growth Patterns and Growth Velocity of Indian Babies. (Longitudinal Growth of Indian Children). Research Report No. 4.

ERIC Educational Resources Information Center

Phatak, Pramila; And Others

This study reports various aspects of the analyses carried out on the longitudinal data reported in a previous study (PS 007 345) for determining the general growth patterns and growth velocity of mental and motor development. Preliminary analyses focused on the selection of the growth curve, its evaluation in the 208 individual cases, and the…

Second Language Acquisition at the Early Childhood Level: A 5-Year Longitudinal Case Study of Pre-Kindergarten through First-Grade Students

ERIC Educational Resources Information Center

Billak, Bonnie

2013-01-01

This 5-year longitudinal study investigated the English language acquisition and development of students in pre-Kindergarten through Grade 1 at a U.S.-accredited international school. Of the 1,509 students tested, the overwhelming majority were nonnative English speakers. The data provide valuable insight into the rate of second language…

Long-term variability of sleep bruxism and psychological stress in patients with jaw-muscle pain: Report of two longitudinal clinical cases.

PubMed

Muzalev, K; Visscher, C M; Koutris, M; Lobbezoo, F

2018-02-01

Sleep bruxism (SB) and psychological stress are commonly considered as contributing factors in the aetiology of temporomandibular disorder (TMD) pain. However, the lack of longitudinal studies and fluctuating nature of SB, psychological stress and TMD pain have led to contradictory results regarding the association between the possible aetiological factors and TMD pain. In the present study we investigated the contribution of SB and psychological stress to TMD pain in a longitudinal study of 2 clinical TMD pain cases during a 6-week study protocol. Two female volunteers with clinically diagnosed myalgia based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) participated in the study. Questionnaires were used to record jaw-muscle pain and psychological stress experience, and an ambulatory polysomnography technique was used to record SB intensity. Visual analysis of the data revealed that the intensity of TMD pain was not hardwired, neither with psychological stress experience nor with increased SB activity. Within the limitations of single-patient clinical cases design, our study suggested that the presence of TMD pain cannot be explained by a simple linear model which takes psychological stress or SB into account. It also seems that psychological stress was a more important predictor factor for TMD pain than SB. © 2017 John Wiley & Sons Ltd.

Temporal association of cannabis use with symptoms in individuals at clinical high risk for psychosis.

PubMed

Corcoran, Cheryl M; Kimhy, David; Stanford, Arielle; Khan, Shamir; Walsh, Julie; Thompson, Judy; Schobel, Scott; Harkavy-Friedman, Jill; Goetz, Ray; Colibazzi, Tiziano; Cressman, Victoria; Malaspina, Dolores

2008-12-01

Cannabis use is reported to increase the risk for psychosis, but no prospective study has longitudinally examined drug use and symptoms concurrently in clinical high risk cases. We prospectively followed for up to 2 years 32 cases who met research criteria for prodromal psychosis to examine the relationship between substance use and clinical measures. Cases with a baseline history of cannabis use (41%) were older, but did not differ in clinical measures. Longitudinal assessments showed these cases had significantly more perceptual disturbances and worse functioning during epochs of increased cannabis use that were unexplained by concurrent use of other drugs or medications. These data demonstrate that cannabis use may be a risk factor for the exacerbation of subthreshold psychotic symptoms, specifically perceptual disturbances, in high risk cases.

Carotid endarterectomy: comparison of complications between transverse and longitudinal incision.

PubMed

Mendes, George A C; Zabramski, Joseph M; Elhadi, Ali M; Kalani, M Yashar S; Preul, Mark C; Nakaji, Peter; Spetzler, Robert F

2014-08-01

Cranial nerve injury (CNI) is the most common neurological complication associated with carotid endarterectomy (CEA). Some authors postulate that the transverse skin incision leads to increased risk of CNI. We compared the incidence of CNI associated with the transverse and longitudinal skin incisions in a high-volume cerebrovascular center. We reviewed the charts of 226 consecutive patients who underwent CEAs between January 2007 and August 2009. Pre- and postoperative standardized neurological evaluations were performed by faculty neurologists and neurosurgeons. One hundred sixty nine of 226 (75%) CEAs were performed with the use of a transverse incision. The longitudinal incision was generally reserved for patients with a high-riding carotid bifurcation. Mean patient age was 69 years (range, 45-91 years); 62% were men; 59% of patients were symptomatic and had high-grade stenosis (70%-99%). CNI occurred in 8 cases (3.5%): 5 (3%) in transverse and 3 (5.3%) with longitudinal incisions (P = .42). There were 2 marginal mandibular nerve injuries, 1 (0.6%) transverse and 1 longitudinal; 5 recurrent laryngeal nerve injuries, 4 transverse and 1 longitudinal; and 1 case of hypoglossal nerve injury associated with longitudinal incision. One hematoma was associated with CNI. All injuries were transient. Fourteen wound hematomas required surgical evacuation. The transverse skin incision for CEAs is not associated with an increased risk of CNI (P =.42). In this study, the incidence of CNI associated with the transverse incision was 3% (n = 5) vs 5% (n = 3) for longitudinal incisions. All CNIs were temporary.

Longitudinal MR cortical thinning of individuals and its correlation with PET metabolic reduction: a measurement consistency and correctness studies

NASA Astrophysics Data System (ADS)

Lin, Zhongmin S.; Avinash, Gopal; McMillan, Kathryn; Yan, Litao; Minoshima, Satoshi

2014-03-01

Cortical thinning and metabolic reduction can be possible imaging biomarkers for Alzheimer's disease (AD) diagnosis and monitoring. Many techniques have been developed for the cortical measurement and widely used for the clinical statistical studies. However, the measurement consistency of individuals, an essential requirement for a clinically useful technique, requires proper further investigation. Here we leverage our previously developed BSIM technique 1 to measure cortical thickness and thinning and use it with longitudinal MRI from ADNI to investigate measurement consistency and spatial resolution. 10 normal, 10 MCI, and 10 AD subjects in their 70s were selected for the study. Consistent cortical thinning patterns were observed in all baseline and follow up images. Rapid cortical thinning was shown in some MCI and AD cases. To evaluate the correctness of the cortical measurement, we compared longitudinal cortical thinning with clinical diagnosis and longitudinal PET metabolic reduction measured using 3D-SSP technique2 for the same person. Longitudinal MR cortical thinning and corresponding PET metabolic reduction showed high level pattern similarity revealing certain correlations worthy of further studies. Severe cortical thinning that might link to disease conversion from MCI to AD was observed in two cases. In summary, our results suggest that consistent cortical measurements using our technique may provide means for clinical diagnosis and monitoring at individual patient's level and MR cortical thinning measurement can complement PET metabolic reduction measurement.

What Happens to a Nursing Home Chain When Private Equity Takes Over? A Longitudinal Case Study.

PubMed

Bos, Aline; Harrington, Charlene

2017-01-01

We analyzed what happens to a nursing home chain when private equity takes over, with regard to strategy, financial performance, and resident well-being. We conducted a longitudinal (2000-2012) case study of a large nursing home chain that triangulated qualitative and quantitative data from 5 different data sources. Results show that private equity owners continued and reinforced several strategies that were already put in place before the takeover, including a focus on keeping staffing levels low; the new owners added restructuring, rebranding, and investment strategies such as establishing new companies, where the nursing home chain served as an essential "launch customer."

How a Young Child Learns How to Take Part in Mealtimes in a Japanese Day-Care Center: A Longitudinal Case Study

ERIC Educational Resources Information Center

Ishiguro, Hiroaki

2016-01-01

This research is a longitudinal, ethnographic study that focuses on mealtimes with one boy from 9 to 78 months of age in a day-care center in Japan. It looks at routine interactions between a child, his nursery teachers, and the environment, which is a shared and mutually available communicative space between participants in collaboration. The aim…

Information Systems in Teacher Preparation Programs: What Can We Learn from a 5-Year Longitudinal Case Study of an Electronic Portfolio Database?

ERIC Educational Resources Information Center

Swan, Gerry

2009-01-01

In 2003, a portfolio system was implemented to manage the data associated with the field experiences in a teacher education program at a research institution in the southeast region of the United States. In this longitudinal study, the implementation trends from usage data extracted from the system are used to discuss the implications for the use…

Educational Subculture and Dropping out in Higher Education: A Longitudinal Case Study

ERIC Educational Resources Information Center

Venuleo, C.; Mossi, P.; Salvatore, S.

2016-01-01

The paper tests longitudinally the hypothesis that educational subcultures in terms of which students interpret their role and their educational setting affect the probability of dropping out of higher education. A logistic regression model was performed to predict drop out at the beginning of the second academic year for the 823 freshmen of a…

Accolades and Recommendations: A Longitudinal Analysis of Monitoring Reports for Two Charter Schools Serving Native American Students

ERIC Educational Resources Information Center

Anderson, Derek L.; Holder, K. C.

2012-01-01

This longitudinal case study examines 10 years' worth of annual monitoring reports for two rural Native American Charter Schools. Using data from multiple sources including interviews, site visits, and document analyses, the authors used provisional coding and constant comparison analysis to categorize the accolades and recommendations embedded in…

A longitudinal test of the demand-control model using specific job demands and specific job control.

PubMed

de Jonge, Jan; van Vegchel, Natasja; Shimazu, Akihito; Schaufeli, Wilmar; Dormann, Christian

2010-06-01

Supportive studies of the demand-control (DC) model were more likely to measure specific demands combined with a corresponding aspect of control. A longitudinal test of Karasek's (Adm Sci Q. 24:285-308, 1) job strain hypothesis including specific measures of job demands and job control, and both self-report and objectively recorded well-being. Job strain hypothesis was tested among 267 health care employees from a two-wave Dutch panel survey with a 2-year time lag. Significant demand/control interactions were found for mental and emotional demands, but not for physical demands. The association between job demands and job satisfaction was positive in case of high job control, whereas this association was negative in case of low job control. In addition, the relation between job demands and psychosomatic health symptoms/sickness absence was negative in case of high job control and positive in case of low control. Longitudinal support was found for the core assumption of the DC model with specific measures of job demands and job control as well as self-report and objectively recorded well-being.

Long-term impacts of unconventional drilling operations on human and animal health.

PubMed

Bamberger, Michelle; Oswald, Robert E

2015-01-01

Public health concerns related to the expansion of unconventional oil and gas drilling have sparked intense debate. In 2012, we published case reports of animals and humans affected by nearby drilling operations. Because of the potential for long-term effects of even low doses of environmental toxicants and the cumulative impact of exposures of multiple chemicals by multiple routes of exposure, a longitudinal study of these cases is necessary. Twenty-one cases from five states were followed longitudinally; the follow-up period averaged 25 months. In addition to humans, cases involved food animals, companion animals and wildlife. More than half of all exposures were related to drilling and hydraulic fracturing operations; these decreased slightly over time. More than a third of all exposures were associated with wastewater, processing and production operations; these exposures increased slightly over time. Health impacts decreased for families and animals moving from intensively drilled areas or remaining in areas where drilling activity decreased. In cases of families remaining in the same area and for which drilling activity either remained the same or increased, no change in health impacts was observed. Over the course of the study, the distribution of symptoms was unchanged for humans and companion animals, but in food animals, reproductive problems decreased and both respiratory and growth problems increased. This longitudinal case study illustrates the importance of obtaining detailed epidemiological data on the long-term health effects of multiple chemical exposures and multiple routes of exposure that are characteristic of the environmental impacts of unconventional drilling operations.

Relegation and Reversion: Longitudinal Analysis of School Turnaround and Decline

ERIC Educational Resources Information Center

Hochbein, Craig

2012-01-01

School turnaround has become a popular strategy for improvement of chronically low-performing schools. Research related to school turnaround has relied substantially upon case studies. These case studies often focus on successful turnarounds and report immediate outcomes, failing to provide information about the sustainability of the results. In…

Mapping a Process of Negotiated Identity among Incarcerated Male Juvenile Offenders

ERIC Educational Resources Information Center

Abrams, Laura S.; Hyun, Anna

2009-01-01

Building on theories of youth identity transitions, this study maps a process of negotiated identity among incarcerated young men. Data are drawn from ethnographic study of three juvenile correctional institutions and longitudinal semistructured interviews with facility residents. Cross-case analysis of 10 cases that finds youth offenders adapted…

Blended and Online Learning: Student Perceptions and Performance

ERIC Educational Resources Information Center

Adam, Stewart; Nel, Deon

2009-01-01

Purpose: The purpose of this paper is to improve educator knowledge of the antecedents and consequences of blended learning in higher education. Design/methodology/approach: A longitudinal case study approach is adopted. Three case studies each involve tracking a student evaluations of teaching (SET) measure (willingness to recommend) and grade…

Phonological Precedence in Dyslexia: A Case Study

ERIC Educational Resources Information Center

Schneider-Zioga, Patricia

2012-01-01

Developmental dyslexia is believed to involve a phonological deficit of which the exact properties have not been clearly established. This article presents the findings of a longitudinal case study that suggest that, at least for some people with dyslexia, the fundamental problem involves a disturbance of temporal-spatial ordering abilities. A…

A Manual for the Illinois Student Longitudinal Case Study System (ISLCS). Procedures and Materials for Planning and Implementing the ISLCS.

ERIC Educational Resources Information Center

Carvell, Fred; Carvell, Joan B.

Designed for local school and district vocational educators, this manual contains instructions and materials necessary to plan and implement a student longitudinal followup system. Part 1 provides background information and definitions used in the system. In part 2 are described the 11 major activities that must be undertaken by local program…

Effects of Early and Later Family Violence on Children's Behavior Problems and Depression: A Longitudinal, Multi-Informant Perspective

ERIC Educational Resources Information Center

Sternberg, Kathleen J.; Lamb, Michael E.; Guterman, Eva; Abbott, Craig B.

2006-01-01

Objectives: To examine the effects of different forms of family violence at two developmental stages by assessing a sample of 110 Israeli children, drawn from the case files of Israeli family service agencies, studied longitudinally in both middle childhood and adolescence. Methods: Information about the children's adjustment was obtained from…

[SPECIFIC DIAGNOSTIC SIGNIFICANCE OF "RIPPLE SIGN" OF MEDIAL FEMORAL CONDYLE UNDER ARTHROSCOPE IN MEDIAL LONGITUDINAL MENISCAL TEARS].

PubMed

Ren Shiyou; Sun, Limang; Chen, Guofei; Jiang, Changqing; Zhang, Xintao; Zhang Wentao

2015-01-01

To investigate the reliability of the "ripple sign" on the upper surface of the medial femoral condyle in the diagnosis of medial longitudinal meniscal tears under arthroscope. Between June 2013 and June 2014, 56 patients with knee injuries were included. There were 35 males and 21 females with an average age of 22.2 years (range, 12-38 years). The causes of injury were sports in 40 cases, falling in 10 cases, and traffic accident in 6 cases. The injury was located at the left knee in 22 cases and at the right knee in 34 cases. The disease duration was 10-40 days (mean, 20.2 days). Of 56 patients, 15 cases had simple medial meniscal injury; 41 cases had combined injuries, including anterior cruciate ligament injury in 38 cases, posterior cruciate ligament injury in 2 cases, and patellar dislocation in 1 case. The "ripple sign" was observed under arthroscope before operation. Repair of medial meniscal injury and reconstruction of cruciate ligament were performed. The positive "ripple sign" was seen under arthroscope in all patients, who were diagnosed to have longitudinal meniscal tears, including 23 cases of mild "ripple sign" , 28 cases of moderate "ripple sign", and 5 cases of severe "ripple sign". The "ripple sign" on the upper surface of the medial femoral condyle is a reliable diagnostic evidence of medial longitudinal meniscal tears.

Boosting Reading Fluency: An Intervention Case Study at Subword Level

ERIC Educational Resources Information Center

Kairaluoma, Leila; Ahonen, Timo; Aro, Mikko; Holopainen, Leena

2007-01-01

This study is an intervention case study of fluency in Finnish-speaking children with dyslexia. Two 7-year-old children, a girl and a boy, were selected from the Jyvaskyla Longitudinal Study of Dyslexia. The intervention emphasised syllables as reading units, and proceeded from reading syllables to reading words and text. Letter knowledge, reading…

The evaluation of complex interventions in palliative care: an exploration of the potential of case study research strategies.

PubMed

Walshe, Catherine

2011-12-01

Complex, incrementally changing, context dependent and variable palliative care services are difficult to evaluate. Case study research strategies may have potential to contribute to evaluating such complex interventions, and to develop this field of evaluation research. This paper explores definitions of case study (as a unit of study, a process, and a product) and examines the features of case study research strategies which are thought to confer benefits for the evaluation of complex interventions in palliative care settings. Ten features of case study that are thought to be beneficial in evaluating complex interventions in palliative care are discussed, drawing from exemplars of research in this field. Important features are related to a longitudinal approach, triangulation, purposive instance selection, comprehensive approach, multiple data sources, flexibility, concurrent data collection and analysis, search for proving-disproving evidence, pattern matching techniques and an engaging narrative. The limitations of case study approaches are discussed including the potential for subjectivity and their complex, time consuming and potentially expensive nature. Case study research strategies have great potential in evaluating complex interventions in palliative care settings. Three key features need to be exploited to develop this field: case selection, longitudinal designs, and the use of rival hypotheses. In particular, case study should be used in situations where there is interplay and interdependency between the intervention and its context, such that it is difficult to define or find relevant comparisons.

Human longevity and variation in GH/IGF-1/insulin signaling, DNA damage signaling and repair and pro/antioxidant pathway genes: cross sectional and longitudinal studies.

PubMed

Soerensen, Mette; Dato, Serena; Tan, Qihua; Thinggaard, Mikael; Kleindorp, Rabea; Beekman, Marian; Jacobsen, Rune; Suchiman, H Eka D; de Craen, Anton J M; Westendorp, Rudi G J; Schreiber, Stefan; Stevnsner, Tinna; Bohr, Vilhelm A; Slagboom, P Eline; Nebel, Almut; Vaupel, James W; Christensen, Kaare; McGue, Matt; Christiansen, Lene

2012-05-01

Here we explore association with human longevity of common genetic variation in three major candidate pathways: GH/IGF-1/insulin signaling, DNA damage signaling and repair and pro/antioxidants by investigating 1273 tagging SNPs in 148 genes composing these pathways. In a case-control study of 1089 oldest-old (age 92-93) and 736 middle-aged Danes we found 1 pro/antioxidant SNP (rs1002149 (GSR)), 5 GH/IGF-1/INS SNPs (rs1207362 (KL), rs2267723 (GHRHR), rs3842755 (INS), rs572169 (GHSR), rs9456497 (IGF2R)) and 5 DNA repair SNPs (rs11571461 (RAD52), rs13251813 (WRN), rs1805329 (RAD23B), rs2953983 (POLB), rs3211994 (NTLH1)) to be associated with longevity after correction for multiple testing. In a longitudinal study with 11 years of follow-up on survival in the oldest-old Danes we found 2 pro/antioxidant SNPs (rs10047589 (TNXRD1), rs207444 (XDH)), 1 GH/IGF-1/INS SNP (rs26802 (GHRL)) and 3 DNA repair SNPs (rs13320360 (MLH1), rs2509049 (H2AFX) and rs705649 (XRCC5)) to be associated with mortality in late life after correction for multiple testing. When examining the 11 SNPs from the case-control study in the longitudinal data, rs3842755 (INS), rs13251813 (WRN) and rs3211994 (NTHL1) demonstrated the same directions of effect (p<0.05), while rs9456497 (IGF2R) and rs1157146 (RAD52) showed non-significant tendencies, indicative of effects also in late life survival. In addition, rs207444 (XDH) presented the same direction of effect when inspecting the 6 SNPs from the longitudinal study in the case-control data, hence, suggesting an effect also in survival from middle age to old age. No formal replications were observed when investigating the 11 SNPs from the case-control study in 1613 oldest-old (age 95-110) and 1104 middle-aged Germans, although rs11571461 (RAD52) did show a supportive non-significant tendency (OR=1.162, 95% CI=0.927-1.457). The same was true for rs10047589 (TNXRD1) (HR=0.758, 95%CI=0.543-1.058) when examining the 6 SNPs from the longitudinal study in a Dutch longitudinal cohort of oldest-old (age 85+, N=563). In conclusion, the present candidate gene based association study, the largest to date applying a pathway approach, not only points to potential new longevity loci, but also underlines the difficulties of replicating association findings in independent study populations and thus the difficulties in identifying universal longevity polymorphisms. Copyright © 2012 Elsevier Inc. All rights reserved.

What Happens to a Nursing Home Chain When Private Equity Takes Over? A Longitudinal Case Study

PubMed Central

Bos, Aline; Harrington, Charlene

2017-01-01

We analyzed what happens to a nursing home chain when private equity takes over, with regard to strategy, financial performance, and resident well-being. We conducted a longitudinal (2000-2012) case study of a large nursing home chain that triangulated qualitative and quantitative data from 5 different data sources. Results show that private equity owners continued and reinforced several strategies that were already put in place before the takeover, including a focus on keeping staffing levels low; the new owners added restructuring, rebranding, and investment strategies such as establishing new companies, where the nursing home chain served as an essential “launch customer.” PMID:29161948

Transverse versus Longitudinal Incisions for Femoral Artery Exposure in Treating Patients with Peripheral Vascular Disease.

PubMed

Parikh, Punam P; Rubio, Gustavo A; Patel, Kunal; Gupta, Kapil; Jones, Keith; Rey, Jorge; Robinson, Handel

2018-02-01

This study evaluates differences in wound complication rate when transverse versus longitudinal incision is utilized to expose femoral vessels in managing patients with peripheral vascular disease. A retrospective review from 2013 to 2015 was conducted of 150 patients undergoing 156 lower extremity revascularizations with femoral artery exposure through a groin incision. Patients were stratified into 2 groups, transverse versus longitudinal groin incision. Data were reviewed for 3 surgeons that utilize either transverse or longitudinal groin incision in patients undergoing common or iliofemoral endarterectomies, or where femoral artery was used as inflow and/or outflow vessel for limb revascularization. Each group had a comparative outcomes analysis based on incision type. The primary outcome was wound complication, defined as any wound infection, lymphocele, hematoma, dehiscence, pseudoaneurysm, or necrosis. Other outcomes studied included unplanned return to operating room for wound complication, wound vacuum therapy, and soft-tissue flap closure. Data were analyzed using 2-tailed chi-squared test and Student's t-test. Patients in the transverse (n = 85 cases) versus longitudinal (n = 71 cases) cohorts were similar in relation to demographics and comorbidities. Overall mean follow-up was 220 days. Patients with a transverse as compared to longitudinal incision had a significantly lower overall wound complication rate, 7% vs. 42%, respectively (P < 0.001). Furthermore, transverse incisions were associated with lower incidence of unplanned return to the operating room to manage wound complications than patients with a longitudinal incision (5% vs. 23%, respectively; P < 0.001). Transverse versus longitudinal incisions were also associated with significantly lower need for wound vacuum therapy (6% vs. 15%, respectively; P < 0.05) and muscle flap closure (0% vs. 13%, respectively; P < 0.001) for wound complications. Transverse groin incisions for femoral artery exposure may offer a lower risk of wound complications for open procedures as compared to a longitudinal incision. While longitudinal incisions may have higher wound complication rates, incisional approach is contingent on anatomical circumstance and treated disease pattern. Patients should undergo appropriate preoperative counseling regarding wound healing in preparation for limb revascularization. Copyright © 2017 Elsevier Inc. All rights reserved.

An Investigation of GeoBase Mission Data Set Design, Implementation, and Usage Within Air Force Civil Engineer Electrical and Utilities Work Centers

DTIC Science & Technology

2005-03-01

ethnography , grounded theory , phenomenological , case study , and content analysis. As ethnography is based upon a longitudinal study in...a qualitative methodology consisting of a case study strategy is warranted for this research project. Yin (2003) lists five components of research ...systems. Journal of End User Computing, 12(3), 14. Yin, R. K. (2003). Case Study Research : Design and

Longitudinal assessment of short-term memory deterioration in a logopenic variant primary progressive aphasia with post-mortem confirmed Alzheimer's Disease pathology.

PubMed

Tree, Jeremy; Kay, Janice

2015-09-01

In the field of dementia research, there are reports of neurodegenerative cases with a focal loss of language, termed primary progressive aphasia (PPA). Currently, this condition has been further sub-classified, with the most recent sub-type dubbed logopenic variant (PPA-LV). As yet, there remains somewhat limited evaluation of the characteristics of this condition, with no studies providing longitudinal assessment accompanied by post-mortem examination. Moreover, a key characteristic of the PPA-LV case is a deterioration of phonological short-term memory, but again little work has scrutinized the nature of this impairment over time. The current study seeks to redress these oversights and presents detailed longitudinal examination of language and memory function in a case of PPA-LV, with special focus on tests linked to components of phonological short-term memory function. Our findings are then considered with reference to a contemporary model of the neuropsychology of phonological short-term memory. Additionally, post-mortem examinations indicated Alzheimer's disease type pathology, providing further evidence that the PPA-LV presentation may reflect an atypical presentation of this condition. © 2014 The British Psychological Society.

Four-year longitudinal study of mandibular dysfunction in children.

PubMed

Magnusson, T; Egermark-Eriksson, I; Carlsson, G E

1985-04-01

A longitudinal study of clinical signs and subjective symptoms of mandibular dysfunction was performed with a 4-yr interval in 119 children, now 11 and 15 yr old. The results showed that 66% in both age groups had clinical signs while 62 and 66%, respectively, complained of subjective symptoms. In most cases the signs were mild, but 11% of the 11-yr-olds and 17% of the 15-yr-olds had moderate, or, in a few cases, severe signs of dysfunction. Most of the children with subjective symptoms had their symptoms occasionally but 3% in the younger and 11% in the older age group had frequent symptoms from the masticatory system. When comparisons were made with the findings 4 yr earlier, it was noted that the subjective symptoms had increased in frequency in the younger children, while the clinical signs had increased in both groups. These age differences, as well as the prevalence figures recorded longitudinally, agreed well with previous findings in cross-sectional investigations of different age groups.

Serum carotenoid and tocopherol concentrations and risk of asthma in childhood: a nested case-control study.

PubMed

Hämäläinen, N; Nwaru, B I; Erlund, I; Takkinen, H-M; Ahonen, S; Toppari, J; Ilonen, J; Veijola, R; Knip, M; Kaila, M; Virtanen, S M

2017-03-01

The antioxidant hypothesis regarding the risk of asthma in childhood has resulted in inconsistent findings. Some data indicate that the role of antioxidants in childhood asthma risk may have a critical time window of effect, but only a well-designed longitudinal cohort study can clarify this hypothesis. To study the longitudinal associations between serum carotenoid and tocopherol concentrations during the first 4 years of life and asthma risk by the age of 5 years. Based on a case-control design nested within a Finnish birth cohort, 146 asthma cases were matched to 270 controls on birth time, sex, genetic risk, and birth place. Non-fasting blood samples were collected at the ages of 1, 1.5, 2, 3, and 4 years and serum carotenoids and tocopherols were analysed. Parents reported the presence and age at start of persistent doctor-diagnosed asthma in the child at the age of 5 years. Data analyses were conducted using generalized estimating equations. We did not find strong associations between serum carotenoids and tocopherols and the risk of asthma based on age-specific and longitudinal analyses. Both lower and higher quarters of α-carotene and γ-tocopherol increased the risk of asthma. The current findings do not support the suggestion that the increased prevalence of asthma may be a consequence of decreased intake of antioxidant nutrients. Moreover, we did not confirm any critical time window of impact of antioxidants on asthma risk. Replication of these findings in similar longitudinal settings will strengthen this evidence base. © 2017 John Wiley & Sons Ltd.

Scaling up STEM Academies Statewide: Implementation, Network Supports, and Early Outcomes

ERIC Educational Resources Information Center

Young, Viki; House, Ann; Sherer, David; Singleton, Corinne; Wang, Haiwen; Klopfenstein, Kristin

2016-01-01

This chapter presents a case study of scaling up the T-STEM initiative in Texas. Data come from the four-year longitudinal evaluation of the Texas High School Project (THSP). The evaluation studied the implementation and impact of T-STEM and the other THSP reforms using a mixed-methods design, including qualitative case studies; principal,…

The Asset-Burden Paradox of Giftedness: A 15-Year Phenomenological, Longitudinal Case Study

ERIC Educational Resources Information Center

Peterson, Jean Sunde

2012-01-01

A 15-year phenomenological case study of an exceptional female from age 15 through 30 was focused on exploring the subjective experience of development during adolescence and young adulthood, with attention to how giftedness and context interacted. The main focus became her response to trauma, which was revealed early in the study. Data, including…

Estimators for longitudinal latent exposure models: examining measurement model assumptions.

PubMed

Sánchez, Brisa N; Kim, Sehee; Sammel, Mary D

2017-06-15

Latent variable (LV) models are increasingly being used in environmental epidemiology as a way to summarize multiple environmental exposures and thus minimize statistical concerns that arise in multiple regression. LV models may be especially useful when multivariate exposures are collected repeatedly over time. LV models can accommodate a variety of assumptions but, at the same time, present the user with many choices for model specification particularly in the case of exposure data collected repeatedly over time. For instance, the user could assume conditional independence of observed exposure biomarkers given the latent exposure and, in the case of longitudinal latent exposure variables, time invariance of the measurement model. Choosing which assumptions to relax is not always straightforward. We were motivated by a study of prenatal lead exposure and mental development, where assumptions of the measurement model for the time-changing longitudinal exposure have appreciable impact on (maximum-likelihood) inferences about the health effects of lead exposure. Although we were not particularly interested in characterizing the change of the LV itself, imposing a longitudinal LV structure on the repeated multivariate exposure measures could result in high efficiency gains for the exposure-disease association. We examine the biases of maximum likelihood estimators when assumptions about the measurement model for the longitudinal latent exposure variable are violated. We adapt existing instrumental variable estimators to the case of longitudinal exposures and propose them as an alternative to estimate the health effects of a time-changing latent predictor. We show that instrumental variable estimators remain unbiased for a wide range of data generating models and have advantages in terms of mean squared error. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Assessing the Impact of Research: A Case Study of the LSAY Research Innovation and Expansion Fund. Longitudinal Surveys of Australian Youth. Occasional Paper

ERIC Educational Resources Information Center

Hargreaves, Jo

2012-01-01

The purpose of this project is to apply the framework developed by the National Centre for Vocational Education Research (NCVER) for measuring research impact to assess the outcomes of the research and activities funded under the Longitudinal Surveys of Australian Youth (LSAY) Research Innovation and Expansion Fund (RIEF). LSAY provides a rich…

Evaluation of Oral Performance in Outsourced Call Centres: An Exploratory Case Study

ERIC Educational Resources Information Center

Friginal, Eric

2013-01-01

This case study discusses the development and use of an oral performance assessment instrument intended to evaluate Filipino agents' customer service transactions with callers from the United States (US). The design and applications of the instrument were based on a longitudinal, qualitative observation of language training and customer service…

Educational Implications of the Subtle Late Effects of Childhood Leukemia Medical Treatment: A Case Study

ERIC Educational Resources Information Center

Lavach, John F.; Hart, Juliet E.

2008-01-01

This paper presents a four-year longitudinal case study of a nine-year-old student when he was diagnosed with leukemia. Cognitive, neuropsychological, and affective functioning both pre and post chemotherapy treatment were assessed. Full neuropsychological evaluation revealed difficulties with processing speed, concentration, and organization…

Transforming Engagement: A Case Study of Building Intrinsic Motivation in a Child with Autism

ERIC Educational Resources Information Center

Dearden, Jackie; Emerson, Anne; Lewis, Tom; Papp, Rebecca

2017-01-01

This longitudinal case study of a 10-year-old girl with autism and severe communication impairment measures the impact of the MORE (Means, Opportunities, Reasons and Expectations) approach to enhancing engagement and communication. Through detailed observation of video data over a period of 28 months, engagement behaviours including interaction…

Distributed Leadership with the Aim of "Reculturing": A Departmental Case Study

ERIC Educational Resources Information Center

Melville, Wayne; Jones, Doug; Campbell, Todd

2014-01-01

This article considers a secondary science department that has, since 2000, developed distributed leadership as a form of human capacity building. Using a longitudinal ethnographic case study allowed us to consider how distributed leadership can be nurtured and developed in a department. Our analysis centres on two key issues: the nature and…

Transforming the Corporate Training Function through Developing a Training Strategy and Advisory Board: A Longitudinal Case Study

ERIC Educational Resources Information Center

Kalman, Howard K.

2008-01-01

This study examined use of a strategic planning process to reinvent a corporate training department. The naturalistic case describes how the corporate training function gained credibility and influence with senior management, developed alignment with organizational goals, and began transforming the function into a performance improvement…

Implementing Curriculum Evaluation: Case Study of a Generic Undergraduate Degree in Health Sciences

ERIC Educational Resources Information Center

Harris, Lynne; Driscoll, Peter; Lewis, Melinda; Matthews, Lynda; Russell, Cherry; Cumming, Steven

2010-01-01

This case study presents a longitudinal, evidence-based approach to health science curriculum reform and evaluation. Curriculum in higher education must meet the needs of diverse stakeholders and must respond to dynamic local, national and international contexts, and this creates challenges for evaluation. The long lead time prior to the…

Educational Leadership in a Competitive State: A Contradiction in Terms?

ERIC Educational Resources Information Center

Moos, Lejf

2012-01-01

Purpose: The purpose of this paper is to explore how important the choice of theoretical perspective is on the analyses of empirical data from a Danish case study. Design/methodology/approach: The empirical bases for the analyses are qualitative, longitudinal case studies of school leadership in the International Successful School Principalship…

Implementation at the School Building Level: The Development and Analysis of Nine Mini-Case Studies.

ERIC Educational Resources Information Center

Hall, Gene; And Others

As part of a district-wide longitudinal study of the implementation of a science curriculum innovation, researchers developed case studies of a sample of nine elementary schools in the Jefferson County School District, a large suburban system in Colorado. The study applied the Concerns-Based Adoption Model, which assumes that change is carried out…

A Longitudinal Test of the Demand–Control Model Using Specific Job Demands and Specific Job Control

PubMed Central

van Vegchel, Natasja; Shimazu, Akihito; Schaufeli, Wilmar; Dormann, Christian

2010-01-01

Background Supportive studies of the demand–control (DC) model were more likely to measure specific demands combined with a corresponding aspect of control. Purpose A longitudinal test of Karasek’s (Adm Sci Q. 24:285–308, 1) job strain hypothesis including specific measures of job demands and job control, and both self-report and objectively recorded well-being. Method Job strain hypothesis was tested among 267 health care employees from a two-wave Dutch panel survey with a 2-year time lag. Results Significant demand/control interactions were found for mental and emotional demands, but not for physical demands. The association between job demands and job satisfaction was positive in case of high job control, whereas this association was negative in case of low job control. In addition, the relation between job demands and psychosomatic health symptoms/sickness absence was negative in case of high job control and positive in case of low control. Conclusion Longitudinal support was found for the core assumption of the DC model with specific measures of job demands and job control as well as self-report and objectively recorded well-being. PMID:20195810

A comparison of response rates in the English Longitudinal Study of Ageing and the Health and Retirement Study

PubMed Central

Cheshire, Hayley; Ofstedal, Mary Beth; Scholes, Shaun; Schroeder, Mathis

2013-01-01

Survey response rates are an important measure of the quality of a survey; this is true for both longitudinal and cross-sectional surveys. However, the concept of a response rate in the context of a panel survey is more complex than is the case for a cross-sectional survey. There are typically many different response rates that can be calculated for a panel survey, each of which may be relevant for a specific purpose. The main objective of our paper is to document and compare response rates for two long-term panel studies of ageing, the English Longitudinal Study of Ageing (ELSA) and the Health and Retirement Study (HRS) in the United States. To guide our selection and calculation of response rates for the two studies, we use a framework that was developed by Peter Lynn (2005) and present several different types of longitudinal response rates for the two surveys. We discuss similarities and differences in the study designs and protocols and how some of the differences affect comparisons of response rates across the two studies. PMID:24432049

Learning from Multiple Cases: A New Paradigm for Investigating the Effects of Clinical Experience on Knowledge Restructuring and Knowledge Acquisition.

ERIC Educational Resources Information Center

Boshuizen, Henny P. A.; Bongaerts, Maureen Machiels; van de Wiel, Margaretha W. J.; Schmidt, Henk G.

The effects of experience with a series of similar cases on the knowledge restructuring and learning from text were studied in a longitudinal design. Two groups of fourth-year medical students were confronted with a series of cases, part of them having the same underlying disease. The cases were interspersed with fillers, and each set of cases had…

Do Undergraduate Paramedic Students Embrace Case Based Learning Using a Blended Teaching Approach? A 3-Year Review

ERIC Educational Resources Information Center

Williams, Brett

2009-01-01

This paper presents the results of a descriptive longitudinal study which aimed to identify student paramedic perceptions of case based learning used in the clinical curriculum of the Bachelor of Emergency Health (BEH) degree at Monash University, Victoria, Australia. Case based learning and its integration within clinical curriculum is an…

Analysis of Speech Disorders in Acute Pseudobulbar Palsy: a Longitudinal Study of a Patient with Lingual Paralysis.

ERIC Educational Resources Information Center

Leroy-Malherbe, V.; Chevrie-Muller, C.; Rigoard, M. T.; Arabia, C.

1998-01-01

This case report describes the case of a 52-year-old man with bilateral central lingual paralysis following a myocardial infarction. Analysis of speech recordings 15 days and 18 months after the attack were acoustically analyzed. The case demonstrates the usefulness of acoustic analysis to detect slight acoustic differences. (DB)

Managing Criticism in Ph.D. Supervision: A Qualitative Case Study

ERIC Educational Resources Information Center

Li, Sarah; Seale, Clive

2007-01-01

This article is part of a larger study which presents findings from an in-depth longitudinal case study of a student's Ph.D. journey. It shows how criticism is produced and managed in the supervisory relationship. As well as an overview of types of criticism produced across a range of supervisory interactions, the article presents a micro-analysis…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samet, J.; Gilliland, F.D.

This project incorporates two related research projects directed toward understanding respiratory carcinogenesis in radon-exposed former uranium miners. The first project involved a continuation of the tissue resource of lung cancer cases from former underground uranium miners and comparison cases from non-miners. The second project was a pilot study for a proposed longitudinal study of respiratory carcinogenesis in former uranium miners. The objectives including facilitating the investigation of molecular changes in radon exposed lung cancer cases, developing methods for prospectively studying clinical, cytologic, cytogenetic, and molecular changes in the multi-event process of respiratory carcinogenesis, and assessing the feasibility of recruiting formermore » uranium miners into a longitudinal study that collected multiple biological specimens. A pilot study was conducted to determine whether blood collection, induced sputum, bronchial brushing, washings, and mucosal biopsies from participants at two of the hospitals could be included efficiently. A questionnaire was developed for the extended study and all protocols for specimen collection and tissue handling were completed. Resource utilization is in progress at ITRI and the methods have been developed to study molecular and cellular changes in exfoliated cells contained in sputum as well as susceptibility factors.« less

System Learning in an Urban School District: A Case Study of Intra-District Learning

ERIC Educational Resources Information Center

Redding, Christopher; Cannata, Marisa; Miller, Jason

2017-01-01

This paper presents evidence from a unique reform model that allowed teachers and other educators in a large urban district to collaborate with one another in the development of an innovation meant to improve student ownership and responsibility. In this longitudinal case study, we describe school stakeholders' learning about the design, the…

Fieldwork, Co-Teaching and Co-Generative Dialogue in Lower Secondary School Environmental Science

ERIC Educational Resources Information Center

Rahmawati, Yuli; Koul, Rekha

2016-01-01

This article reports one of the case studies in a 3-year longitudinal study in environmental science education. This case explores the process of teaching about ecosystems through co-teaching and co-generative dialogue in a Year-9 science classroom in Western Australia. Combining with co-teaching and co-generative dialogue aimed at transforming…

Factors Influencing Error Recovery in Collections Databases: A Museum Case Study

ERIC Educational Resources Information Center

Marty, Paul F.

2005-01-01

This article offers an analysis of the process of error recovery as observed in the development and use of collections databases in a university museum. It presents results from a longitudinal case study of the development of collaborative systems and practices designed to reduce the number of errors found in the museum's databases as museum…

System Learning in an Urban School District: A Case Study of Intra-District Learning

ERIC Educational Resources Information Center

Redding, Christopher; Cannata, Marisa; Miller, Jason M.

2018-01-01

This paper presents evidence from a unique reform model that allowed teachers and other educators in a large urban district to collaborate with one another in the development of an innovation meant to improve student ownership and responsibility. In this longitudinal case study, we describe school stakeholders' learning about the design, the…

A Semiparametric Approach to Simultaneous Covariance Estimation for Bivariate Sparse Longitudinal Data

PubMed Central

Das, Kiranmoy; Daniels, Michael J.

2014-01-01

Summary Estimation of the covariance structure for irregular sparse longitudinal data has been studied by many authors in recent years but typically using fully parametric specifications. In addition, when data are collected from several groups over time, it is known that assuming the same or completely different covariance matrices over groups can lead to loss of efficiency and/or bias. Nonparametric approaches have been proposed for estimating the covariance matrix for regular univariate longitudinal data by sharing information across the groups under study. For the irregular case, with longitudinal measurements that are bivariate or multivariate, modeling becomes more difficult. In this article, to model bivariate sparse longitudinal data from several groups, we propose a flexible covariance structure via a novel matrix stick-breaking process for the residual covariance structure and a Dirichlet process mixture of normals for the random effects. Simulation studies are performed to investigate the effectiveness of the proposed approach over more traditional approaches. We also analyze a subset of Framingham Heart Study data to examine how the blood pressure trajectories and covariance structures differ for the patients from different BMI groups (high, medium and low) at baseline. PMID:24400941

A Study of the Nontraditional and Social Impact of Vocational Education on Individuals in Illinois.

ERIC Educational Resources Information Center

Carvell Education Managment Planning, Inc., Los Angeles, CA.

This final report concludes a three-year project to identify the program impact on 125 youths and adults who took vocational education in eight locations in Illinois. The longitudinal case study began in 1978-79 when the subjects were still enrolled in their vocational programs. Many of the students who became case subjects for the study were…

Longitudinal variations of brain functional connectivity: A case report study based on a mouse model of epilepsy.

PubMed

Erramuzpe, A; Encinas, J M; Sierra, A; Maletic-Savatic, M; Brewster, A L; Anderson, Anne E; Stramaglia, S; Cortes, Jesus M

2015-01-01

Brain Functional Connectivity (FC) quantifies statistical dependencies between areas of the brain. FC has been widely used to address altered function of brain circuits in control conditions compared to different pathological states, including epilepsy, a major neurological disorder. However, FC also has the as yet unexplored potential to help us understand the pathological transformation of the brain circuitry. Our hypothesis is that FC can differentiate global brain interactions across a time-scale of days. To this end, we present a case report study based on a mouse model for epilepsy and analyze longitudinal intracranial electroencephalography data of epilepsy to calculate FC changes from the initial insult (status epilepticus) and over the latent period, when epileptogenic networks emerge, and at chronic epilepsy, when unprovoked seizures occur as spontaneous events. We found that the overall network FC at low frequency bands decreased immediately after status epilepticus was provoked, and increased monotonously later on during the latent period. Overall, our results demonstrate the capacity of FC to address longitudinal variations of brain connectivity across the establishment of pathological states.

Neonatal factors among subjects diagnosed with a pervasive developmental disorder in the US.

PubMed

Geier, David; Kern, Janet; Geier, Mark

2018-07-01

Contradictory studies suggest that some neonatal factors may be associated with a pervasive developmental disorder (PDD) diagnosis, but limited data is available from longitudinal, prospective medical record assessments. The present hypothesis-testing longitudinal, case-control study evaluated birth characteristics among cases diagnosed with a PDD in comparison to controls by examining prospectively collected automated medical records within the Vaccine Safety Datalink (VSD) database. Cases were Health Maintenance Organization (HMO)-enrolled from birth until diagnosed with International Classification of Disease, 9th revision (ICD-9) PDD (299.xx) and controls were HMO-enrolled from birth for at least 4.75 years without a PDD diagnosis. The birth characteristics examined included: gender, gestational age in weeks at birth, mean birth weight in grams, Appearance-Pulse-Grimace-Activity-Respiration (APGAR) scores at 1 minute and 5 minutes, and maternal age in years at birth. Cases had a significantly increased male/female ratio relative to controls. By contrast, mean gestational age at birth, mean birth weight, mean maternal age at birth, and mean APGAR scores at 1 minute and 5 minutes were not statistically different among cases compared to controls. This study indicates that cases diagnosed with a PDD as compared to controls do not have significant differences in neonatal factors.

Longitudinal Analysis of the Premature Infant Intestinal Microbiome Prior to Necrotizing Enterocolitis: A Case-Control Study

PubMed Central

Zhou, Yanjiao; Shan, Gururaj; Sodergren, Erica; Weinstock, George; Walker, W. Allan; Gregory, Katherine E.

2015-01-01

Necrotizing enterocolitis (NEC) is an inflammatory disease of the newborn bowel, primarily affecting premature infants. Early intestinal colonization has been implicated in the pathogenesis of NEC. The objective of this prospective case-control study was to evaluate differences in the intestinal microbiota between infants who developed NEC and unaffected controls prior to disease onset. We conducted longitudinal analysis of the 16S rRNA genes of 312 samples obtained from 12 NEC cases and 26 age-matched controls with a median frequency of 7 samples per subject and median sampling interval of 3 days. We found that the microbiome undergoes dynamic development during the first two months of life with day of life being the major factor contributing to the colonization process. Depending on when the infant was diagnosed with NEC (i.e. early vs. late onset), the pattern of microbial progression was different for cases and controls. The difference in the microbiota was most overt in early onset NEC cases and controls. In proximity to NEC onset, the abundances of Clostridium sensu stricto from Clostridia class were significantly higher in early onset NEC subjects comparing to controls. In late onset NEC, Escherichia/Shigella among Gammaproteobacteria, showed an increasing pattern prior to disease onset, and was significantly higher in cases than controls six days before NEC onset. Cronobacter from Gammaproteobacteria was also significantly higher in late onset NEC cases than controls 1-3 days prior to NEC onset. Thus, the specific infectious agent associated with NEC may vary by the age of infant at disease onset. We found that intravenously administered antibiotics may have an impact on the microbial diversity present in fecal material. Longitudinal analysis at multiple time points was an important strategy utilized in this study, allowing us to appreciate the dynamics of the premature infant intestinal microbiome while approaching NEC at various points. PMID:25741698

The Effects of a Midbrain Glioma on Memory and Other Functions: A Longitudinal Single Case Study

ERIC Educational Resources Information Center

Weddell, Rodger A.

2008-01-01

Our understanding of the effects of midbrain damage on cognition is largely based on animal studies, though there have been occasional investigations of the effects of human midbrain lesions on cognition. This investigation of a rare case of a glioma initially confined to the dorsal midbrain explores the effects of disease progression on IQ,…

What Does It Mean to Be Student Centered? An Institutional Case Study of edTPA Implementation

ERIC Educational Resources Information Center

Fayne, Harriet; Qian, Gaoyin

2016-01-01

This longitudinal case study investigated how one School of Education (SOE), situated in an urban, commuter, public university, responded to the New York State mandate to require the edTPA for initial teacher certification. In order to engage faculty in the work of program redesign, SOE administrators employed a covert leadership approach. Based…

Managing Institutional and Sociocultural Challenges through Sociotransformative Constructivism: A Longitudinal Case Study of a High School Science Teacher

ERIC Educational Resources Information Center

Rodriguez, Alberto J.

2015-01-01

Using a case study approach, this manuscript describes the professional transformation of Gary--an Anglo, male novice teacher--by focusing on his first two years of teaching in a culturally diverse and economically disadvantaged school. As a participant of a larger hybrid, intervention project with peers, Gary received multiple hands-on and…

Active transportation measurement : Minneapolis case study.

DOT National Transportation Integrated Search

2013-06-01

This research examines longitudinal bicycle count data to better understand the impact of new bicycle facilities on use. The study site is Minneapolis which has invested close to $25 million over 8 years to improve active transportation facilities as...

Study of spin dynamics and damping on the magnetic nanowire arrays with various nanowire widths

NASA Astrophysics Data System (ADS)

Cho, Jaehun; Fujii, Yuya; Konioshi, Katsunori; Yoon, Jungbum; Kim, Nam-Hui; Jung, Jinyong; Miwa, Shinji; Jung, Myung-Hwa; Suzuki, Yoshishige; You, Chun-Yeol

2016-07-01

We investigate the spin dynamics including Gilbert damping in the ferromagnetic nanowire arrays. We have measured the ferromagnetic resonance of ferromagnetic nanowire arrays using vector-network analyzer ferromagnetic resonance (VNA-FMR) and analyzed the results with the micromagnetic simulations. We find excellent agreement between the experimental VNA-FMR spectra and micromagnetic simulations result for various applied magnetic fields. We find that the same tendency of the demagnetization factor for longitudinal and transverse conditions, Nz (Ny) increases (decreases) as increasing the nanowire width in the micromagnetic simulations while Nx is almost zero value in transverse case. We also find that the Gilbert damping constant increases from 0.018 to 0.051 as the increasing nanowire width for the transverse case, while it is almost constant as 0.021 for the longitudinal case.

A Longitudinal View of the Liberal Arts Curriculum a Decade after Merger: A Multiple Case Study of Community Colleges in Connecticut, Kentucky, and Louisiana

ERIC Educational Resources Information Center

Norton, Ann; Wilson, Kristin

2015-01-01

This study is an examination of the state of the liberal arts curriculum in community colleges in three geographic regions of the United States. From a constructivist paradigm and using globalization theory as a theoretical framework, this multiple case study examined faculty work life and administrative processes related to curriculum change in…

Restoration of longitudinal images.

PubMed

Hu, Y; Frieden, B R

1988-01-15

In this paper, a method of restoring longitudinal images is developed. By using the transfer function for longitudinal objects, and inverse filtering, a longitudinal image may be restored. The Fourier theory and sampling theorems for transverse images cannot be used directly in the longitudinal case. A modification and reasonable approximation are introduced. We have numerically established a necessary relationship between just-resolved longitudinal separation (after inverse filtering), noise level, and the taking conditions of object distance and lens diameter. An empirical formula is also found to well-fit the computed results. This formula may be of use for designing optical systems which are to image longitudinal details, such as in robotics or microscopy.

Bidirectional Cross-Linguistic Influence in Cantonese-English Bilingual Children: The Case of Right-Dislocation

ERIC Educational Resources Information Center

Ge, Haoyan; Matthews, Stephen; Cheung, Lawrence Yam-leung; Yip, Virginia

2017-01-01

This corpus-based study demonstrates a case of bidirectional cross-linguistic influence in the acquisition of right-dislocation by Cantonese-English bilingual children and interprets the results in relation to Hulk and Müller's hypothesis for cross-linguistic influence. Longitudinal data reveal qualitative and quantitative differences between…

Application of pattern mixture models to address missing data in longitudinal data analysis using SPSS.

PubMed

Son, Heesook; Friedmann, Erika; Thomas, Sue A

2012-01-01

Longitudinal studies are used in nursing research to examine changes over time in health indicators. Traditional approaches to longitudinal analysis of means, such as analysis of variance with repeated measures, are limited to analyzing complete cases. This limitation can lead to biased results due to withdrawal or data omission bias or to imputation of missing data, which can lead to bias toward the null if data are not missing completely at random. Pattern mixture models are useful to evaluate the informativeness of missing data and to adjust linear mixed model (LMM) analyses if missing data are informative. The aim of this study was to provide an example of statistical procedures for applying a pattern mixture model to evaluate the informativeness of missing data and conduct analyses of data with informative missingness in longitudinal studies using SPSS. The data set from the Patients' and Families' Psychological Response to Home Automated External Defibrillator Trial was used as an example to examine informativeness of missing data with pattern mixture models and to use a missing data pattern in analysis of longitudinal data. Prevention of withdrawal bias, omitted data bias, and bias toward the null in longitudinal LMMs requires the assessment of the informativeness of the occurrence of missing data. Missing data patterns can be incorporated as fixed effects into LMMs to evaluate the contribution of the presence of informative missingness to and control for the effects of missingness on outcomes. Pattern mixture models are a useful method to address the presence and effect of informative missingness in longitudinal studies.

An Exploratory Case Study of One Early Career Teacher's Evolving Teaching Practice in Northern Canada

ERIC Educational Resources Information Center

Murray-Orr, Anne; Mitton-Kukner, Jennifer

2017-01-01

This paper focuses upon the case of one early career teacher, Don, a participant in a longitudinal study examining the transfer of learning about literacy practices from pre-service teacher education to the classrooms of secondary content area teachers. We followed Don from his B. Ed. program into his first two years of teaching in an Indigenous…

Life on a Tricycle: A Case Study of Language Impairment from 4 to 19

ERIC Educational Resources Information Center

Brinton, Bonnie; Fujiki, Martin; Robinson, Lee A.

2005-01-01

This article presents a longitudinal case study of a child named Cody identified with specific language impairment. Cody was followed from 4 to 19 years of age, at which time he compared his social skills with those of peers: "It's like they're driving sports car and I'm on a tricycle." His initial long- and short-term intervention goals are…

Attention Interchanges at Story-Time: A Case Study from a Deaf and Hearing Twin Pair Acquiring Swedish Sign Language in Their Deaf Family

ERIC Educational Resources Information Center

Cramer-Wolrath, Emelie

2012-01-01

This case study longitudinally analyzes and describes the changes of attentional expressions in interchanges between a pair of fraternal twins, 1 deaf and 1 hearing, from the age of 10-40 months, and their Deaf family members. The video-observed attentional expressions of initiating and reestablishing interchange were grouped in 5 functional…

Pushing and Pulling Sara: A Case Study of the Contrasting Influences of High School and University Experiences on Engineering Agency, Identity, and Participation

ERIC Educational Resources Information Center

Godwin, Allison; Potvin, Geoff

2017-01-01

This manuscript reports a longitudinal case study of how one woman, Sara, who had previously considered dropping out of high school, authored strong mathematics and science identities and purposefully exhibited agency through her experiences in high school science. These experiences empowered her to choose an engineering major in college; however,…

The "Critical Friend" Role in Fostering Reflective Practices and Developing Staff Cohesion: A Case Study in a New Secondary School, New Zealand

ERIC Educational Resources Information Center

Wright, Noeline; Adam, Amina

2015-01-01

This exploratory case study, arising from a longitudinal project into the establishment of a new secondary school in New Zealand, examines reflective practice through critical friend roles among staff. The paper describes, through the lens of Bourdieu's logic of practice, the implementation of a critical friendship approach linked to the school…

Bias in Cross-Sectional Analyses of Longitudinal Mediation: Partial and Complete Mediation under an Autoregressive Model

ERIC Educational Resources Information Center

Maxwell, Scott E.; Cole, David A.; Mitchell, Melissa A.

2011-01-01

Maxwell and Cole (2007) showed that cross-sectional approaches to mediation typically generate substantially biased estimates of longitudinal parameters in the special case of complete mediation. However, their results did not apply to the more typical case of partial mediation. We extend their previous work by showing that substantial bias can…

Narrow-band injection seeding of a terahertz frequency quantum cascade laser: Selection and suppression of longitudinal modes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nong, Hanond, E-mail: Nong.Hanond@rub.de; Markmann, Sergej; Hekmat, Negar

2014-09-15

A periodically poled lithium niobate (PPLN) crystal with multiple poling periods is used to generate tunable narrow-bandwidth THz pulses for injection seeding a quantum cascade laser (QCL). We demonstrate that longitudinal modes of the quantum cascade laser close to the gain maximum can be selected or suppressed according to the seed spectrum. The QCL emission spectra obtained by electro-optic sampling from the quantum cascade laser, in the most favorable case, shows high selectivity and amplification of the longitudinal modes that overlap the frequency of the narrow-band seed. Proper selection of the narrow-band THz seed from the PPLN crystal discretely tunesmore » the longitudinal mode emission of the quantum cascade laser. Moreover, the THz wave build-up within the laser cavity is studied as a function of the round-trip time. When the seed frequency is outside the maximum of the gain spectrum the laser emission shifts to the preferential longitudinal mode.« less

The impact of extended longitudinal observation on the assessment of personality disorders.

PubMed

Pedersen, G; Karterud, S; Hummelen, B; Wilberg, T

2013-11-01

Multiple sources of information are necessary for a valid assessment of personality disorders (PDs). This study investigates the impact of longitudinal observation. The sample comprised 1217 patients from 15 different treatment units. PDs were assessed at admission to treatment using the Structured Clinical Interview for DSM-IV Axis II Personality Disorders (SCID-II) and additional clinical information (best estimate diagnosis). After approximately 18 weeks of treatment, the SCID-II protocols were re-examined at clinical conferences and the diagnostic status reassessed on the basis of longitudinal observations in multiple group situations (longitudinal, expert, all data principle). Using this procedure, 78% of the patients' diagnostic criteria sets were changed, and 32% of patients' diagnostic statuses were changed. Many (32%) patients who were evaluated initially as not having a PD received a PD diagnosis after re-examination. The information provided by customary clinical assessment has important limitations, and longitudinal observation provides additional information that may change the diagnostic status in approximately one-third of PD cases. Copyright © 2013 John Wiley & Sons, Ltd.

Jeans instability of rotating magnetized quantum plasma: Influence of radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joshi, H., E-mail: hjoshi8525@yahoo.com; Pensia, R. K.

2015-07-31

The effect of radiative heat-loss function and rotation on the Jeans instability of quantum plasma is investigated. The basic set of equations for this problem is constructed by considering quantum magnetohydrodynamic (QMHD) model. Using normal mode analysis, the general dispersion relation is obtained. This dispersion relation is studied in both, longitudinal and transverse direction of propagations. In both case of longitudinal and transverse direction of propagation, the Jeans instability criterion is modified due to presence of radiative heat-loss function and quantum correction.

A longitudinal study of urea cycle disorders.

PubMed

Batshaw, Mark L; Tuchman, Mendel; Summar, Marshall; Seminara, Jennifer

2014-01-01

The Urea Cycle Disorders Consortium (UCDC) is a member of the NIH funded Rare Diseases Clinical Research Network and is performing a longitudinal study of 8 urea cycle disorders (UCDs) with initial enrollment beginning in 2006. The consortium consists of 14 sites in the U.S., Canada and Europe. This report summarizes data mining studies of 614 patients with UCDs enrolled in the UCDC's longitudinal study protocol. The most common disorder is ornithine transcarbamylase deficiency, accounting for more than half of the participants. We calculated the overall prevalence of urea cycle disorders to be 1/35,000, with 2/3rds presenting initial symptoms after the newborn period. We found the mortality rate to be 24% in neonatal onset cases and 11% in late onset cases. The most common precipitant of clinical hyperammonemic episodes in the post-neonatal period was intercurrent infections. Elevations in both blood ammonia and glutamine appeared to be biomarkers for neurocognitive outcome. In terms of chronic treatment, low protein diet appeared to result in normal weight but decreased linear growth while N-scavenger therapy with phenylbutyrate resulted in low levels of branched chain amino acids. Finally, we found an unexpectedly high risk for hepatic dysfunction in patients with ornithine transcarbamylase deficiency. This natural history study illustrates how a collaborative study of a rare genetic disorder can result in an improved understanding of morbidity and disease outcome. Copyright © 2014 Elsevier Inc. All rights reserved.

STRUCTURAL AND CONNECTOMIC NEUROIMAGING FOR THE PERSONALIZED STUDY OF LONGITUDINAL ALTERATIONS IN CORTICAL SHAPE, THICKNESS AND CONNECTIVITY AFTER TRAUMATIC BRAIN INJURY

PubMed Central

Irimia, A.; Goh, S.-Y. M.; Torgerson, C. M.; Vespa, P. M.; Van Horn, J. D.

2014-01-01

The integration of longitudinal brain structure analysis with neurointensive care strategies continues to be a substantial difficulty facing the traumatic brain injury (TBI) research community. For patient-tailored case analysis, it remains challenging to establish how lesion profile modulates longitudinal changes in cortical structure and connectivity, as well as how these changes lead to behavioral, cognitive and neural dysfunction. Additionally, despite the clinical potential of morphometric and connectomic studies, few analytic tools are available for their study in TBI. Here we review the state of the art in structural and connectomic neuroimaging for the study of TBI and illustrate a set of recently-developed, patient-tailored approaches for the study of TBI-related brain atrophy and alterations in morphometry as well as inter-regional connectivity. The ability of such techniques to quantify how injury modulates longitudinal changes in cortical shape, structure and circuitry is highlighted. Quantitative approaches such as these can be used to assess and monitor the clinical condition and evolution of TBI victims, and can have substantial translational impact, especially when used in conjunction with measures of neuropsychological function. PMID:24844173

Purposely Teaching for the Promotion of Higher-Order Thinking Skills: A Case of Critical Thinking

ERIC Educational Resources Information Center

Miri, Barak; Ben-Chaim, David; Zoller, Uri

2007-01-01

This longitudinal case-study aimed at examining whether purposely teaching for the promotion of higher order thinking skills enhances students' critical thinking (CT), within the framework of science education. Within a pre-, post-, and post-post experimental design, high school students, were divided into three research groups. The experimental…

On the Limits of Sexual Health Literacy: Insights from Ugandan Schoolgirls

ERIC Educational Resources Information Center

Jones, Shelley; Norton, Bonny

2007-01-01

This article makes the case that current conceptions of sexual health literacy have limited relevance to the Ugandan context because they assume that knowledge of unsafe sexual practices will lead to changes in behavior and lifestyle. Drawing on a longitudinal case study with 15 Ugandan schoolgirls in rural Uganda from August 2004 to September…

Longitudinal associations between different dementia diagnoses and medication use jointly accounting for dropout.

PubMed

Agogo, George O; Ramsey, Christine M; Gnjidic, Danijela; Moga, Daniela C; Allore, Heather

2018-04-18

ABSTRACTBackground:Longitudinal studies of older adults are characterized by high dropout rates, multimorbid conditions, and multiple medication use, especially proximal to death. We studied the association between multiple medication use and incident dementia diagnoses including Alzheimer's disease (AD), vascular dementia (VD), and Lewy-body dementia (LBD), simultaneously accounting for dropout. Using the National Alzheimer's Coordinating Center data with three years of follow-up, a set of covariate-adjusted models that ignore dropout was fit to complete-case data, and to the whole-cohort data. Additionally, covariate-adjusted joint models with shared random effects accounting for dropout were fit to the whole-cohort data. Multiple medication use was defined as polypharmacy (⩾ five medications), hyperpolypharmacy (⩾ ten medications), and total number of medications. Incident diagnoses were 2,032 for AD, 135 for VD, and 139 for LBD. Percentages of dropout at the end of follow-up were as follows: 71.8% for AD, 81.5% for VD, and 77.7% for LBD. The odds ratio (OR) estimate for hyperpolypharmacy among those with LBD versus AD was 2.19 (0.78, 6.15) when estimated using complete-case data and 3.00 (1.66, 5.40) using whole-cohort data. The OR reduced to 1.41 (0.76, 2.64) when estimated from the joint model accounting for dropout. The OR for polypharmacy using complete-case data differed from the estimates using whole-cohort data. The OR for dementia diagnoses on total number of medications was similar, but non-significant when estimated using complete-case data. Reasons for dropout should be investigated and appropriate statistical methods should be applied to reduce bias in longitudinal studies among high-risk dementia cohorts.

Development and Evaluation of a Longitudinal Case-Based Learning (CBL) Experience for a Geriatric Medicine Rotation

ERIC Educational Resources Information Center

Struck, Bryan D.; Teasdale, Thomas A.

2008-01-01

The DWR Department of Geriatric Medicine at OUHSC and the OKC VA Medical Center began a mandatory third-year geriatric medicine clerkship in 2003. As part of the didactic sessions, the Department created a longitudinal Case-Based Learning (CBL) experience. The purpose of this paper is to describe the CBL experience, report student satisfaction…

Growth and resilience of pioneering nonprofit human service organizations: a cross-case analysis of organizational histories.

PubMed

Kimberlin, Sara E; Schwartz, Sara L; Austin, Michael J

2011-01-01

Knowledge of organizational history is important for recognizing patterns in effective management and understanding how organizations respond to internal and external challenges. This cross-case analysis of 12 histories of pioneering nonprofit human service organizations contributes an important longitudinal perspective on organizational history, complementing the cross-sectional case studies that dominate the existing research on nonprofit organizations. The literature on organizational growth, including lifecycle models and growth management, is reviewed, along with the literature on organizational resilience. Based on analysis of the 12 organizational histories, a conceptual model is presented that synthesizes key factors in the areas of leadership, internal operations, and external relations that influence organizational growth and resilience to enable nonprofit organizations to survive and thrive over time. Both cross-sectional and longitudinal examples from the organizational histories illustrate the conceptual map. The paper concludes with a discussion of directions for future research on nonprofit organizational history.

Online versus offline spatiotemporal image correlation (STIC) M-mode for the evaluation of cardiac longitudinal annular displacement in fetal growth restriction.

PubMed

Tanis, Jozien C; Mohammed, Nuruddin; Bennasar, Mar; Martinez, Josep Maria; Bijnens, Bart; Crispi, Fatima; Gratacos, Eduard

2018-07-01

Our first aim was to compare online M-mode with offline spatiotemporal image correlation (STIC) M-mode for assessing longitudinal annular displacement (LAD) in growth-restricted fetuses (FGR). Our second aim was to compare LAD measures of FGR cases with controls. Prospective study including 40 FGR cases (defined estimated fetal weight and birth weight <10th centile) and 72 normally grown fetuses matched to cases by gestational age at scan. LAD was measured with online M-mode and offline STIC M-mode at the left and right ventricular free walls and septum in all fetuses. FGR cases had a significant decrease in LAD by STIC in all sites as compared to controls (e.g. right LAD in FGR mean 6.7 mm (SD 1.2) versus controls 7.2 mm (1.2), p = .033). There was a non-significant trend for lower values in FGR when using online M-mode (e.g. right LAD in FGR 6.9 mm (1.5) versus controls 7.4 mm (1.5), p = .084). STIC M-mode seems a better method than online M-mode for detecting subtle changes in myocardial motion. STIC presents more precise results and allows an ideal placement of the M-mode arrow. These results confirm previous data suggesting decreased longitudinal motion in FGR.

Analysis of radial and longitudinal force of plasma wakefield generated by a chirped pulse laser

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghasemi, Leila; Afhami, Saeedeh; Eslami, Esmaeil, E-mail: eeslami@iust.ac.ir

2015-08-15

In present paper, the chirp effect of an electromagnetic pulse via an analytical model of wakefield generation is studied. Different types of chirps are employed in this study. Our results show that by the use of nonlinear chirped pulse the longitudinal wakefield and focusing force is stronger than that of linear chirped pulse. It is indicated that quadratic nonlinear chirped pulses are globally much efficient than periodic nonlinear chirped pulses. Our calculations also predict that in nonlinear chirped pulse case, the overlap of focusing and accelerating regions is broader than that achieved in linear chirped pulse.

Sociocultural and Academic Considerations for School-Age d/Deaf and Hard of Hearing Multilingual Learners: A Case Study of A Deaf Latina

ERIC Educational Resources Information Center

Baker, Sharon; Scott, Jessica

2016-01-01

For decades, research has focused on American Sign Language/English bilingual education for d/Deaf and hard of hearing students whose families used English or ASL. However, a growing population of d/Dhh children come from households where languages other than English (e.g., Spanish, Chinese, Vietnamese) are used. In a longitudinal case study, the…

Longitudinal patient-oriented outcomes in neuropathy

PubMed Central

Kerber, Kevin; Langa, Kenneth M.; Banerjee, Mousumi; Rodgers, Ann; McCammon, Ryan; Burke, James; Feldman, Eva

2015-01-01

Objective: To evaluate longitudinal patient-oriented outcomes in peripheral neuropathy over a 14-year time period including time before and after diagnosis. Methods: The 1996–2007 Health and Retirement Study (HRS)–Medicare Claims linked database identified incident peripheral neuropathy cases (ICD-9 codes) in patients ≥65 years. Using detailed demographic information from the HRS and Medicare claims, a propensity score method identified a matched control group without neuropathy. Patient-oriented outcomes, with an emphasis on self-reported falls, pain, and self-rated health (HRS interview), were determined before and after neuropathy diagnosis. Generalized estimating equations were used to assess differences in longitudinal outcomes between cases and controls. Results: We identified 953 peripheral neuropathy cases and 953 propensity-matched controls. The mean (SD) age was 77.4 (6.7) years for cases, 76.9 (6.6) years for controls, and 42.1% had diabetes. Differences were detected in falls 3.0 years before neuropathy diagnosis (case vs control; 32% vs 25%, p = 0.008), 5.0 years for pain (36% vs 27%, p = 0.002), and 5.0 years for good to excellent self-rated health (61% vs 74%, p < 0.0001). Over time, the proportion of fallers increased more rapidly in neuropathy cases compared to controls (p = 0.002), but no differences in pain (p = 0.08) or self-rated health (p = 0.9) were observed. Conclusions: In older persons, differences in falls, pain, and self-rated health can be detected 3–5 years prior to peripheral neuropathy diagnosis, but only falls deteriorates more rapidly over time in neuropathy cases compared to controls. Interventions to improve early peripheral neuropathy detection are needed, and future clinical trials should incorporate falls as a key patient-oriented outcome. PMID:26019191

Quantitative diagnostic method for biceps long head tendinitis by using ultrasound.

PubMed

Huang, Shih-Wei; Wang, Wei-Te

2013-01-01

To investigate the feasibility of grayscale quantitative diagnostic method for biceps tendinitis and determine the cut-off points of a quantitative biceps ultrasound (US) method to diagnose biceps tendinitis. Design. Prospective cross-sectional case controlled study. Outpatient rehabilitation service. A total of 336 shoulder pain patients with suspected biceps tendinitis were recruited in this prospective observational study. The grayscale pixel data of the range of interest (ROI) were obtained for both the transverse and longitudinal views of the biceps US. A total of 136 patients were classified with biceps tendinitis, and 200 patients were classified as not having biceps tendinitis based on the diagnostic criteria. Based on the Youden index, the cut-off points were determined as 26.85 for the transverse view and 21.25 for the longitudinal view of the standard deviation (StdDev) of the ROI values, respectively. When the ROI evaluation of the US surpassed the cut-off point, the sensitivity was 68% and the specificity was 90% in the StdDev of the transverse view, and the sensitivity was 81% and the specificity was 73% in the StdDev of the longitudinal view to diagnose biceps tendinitis. For equivocal cases or inexperienced sonographers, our study provides a more objective method for diagnosing biceps tendinitis in shoulder pain patients.

Study of mean- and turbulent-velocity fields in a large-scale turbine-vane passage

NASA Technical Reports Server (NTRS)

Bailey, D. A.

1979-01-01

Laser-Doppler velocimetry, and to a lesser extent hot-wire anemometry, were employed to measure three components of the mean velocity and the six turbulent stresses at four planes within the turbine inlet-guide-vane passage. One variation in the turbulent inlet boundary layer thickness and one variation in the blade aspect ratio (span/axial chord) were studied. A longitudinal vortex (passage vortex) was clearly identified in the exit plane of the passage for the three test cases. The maximum turbulence intensities within the longitudinal vortex were found to be on the order of 2 to 4 percent, with large regions appearing nonturbulent. Because a turbulent wall boundary layer was the source of vorticity that produced the passage vortex, these low turbulence levels were not anticipated. For the three test cases studied, the lateral velocity field extended significantly beyond the region of the longitudinal velocity defect. Changing the inlet boundary layer thickness produced a difference in the location, the strength, and the extent of the passage vortex. Changing the aspect ratio of the blade passage had a measurable but less significant effect. The experiment was performed in a 210 mm pitch, 272 mm axial chord model in low speed wind tunnel at an inlet Mach number of 0.07.

Clinical and dermoscopic clues to differentiate pigmented nail bands: an International Dermoscopy Society study.

PubMed

Benati, E; Ribero, S; Longo, C; Piana, S; Puig, S; Carrera, C; Cicero, F; Kittler, H; Deinlein, T; Zalaudek, I; Stolz, W; Scope, A; Pellacani, G; Moscarella, E; Piraccini, B M; Starace, M; Argenziano, G

2017-04-01

Longitudinal melanonychia might be difficult to differentiate and the use of dermoscopy can be useful for the preoperative evaluation and management decision. The aim of our study was to investigate clinical and dermoscopic criteria of acquired longitudinal melanonychia in adults to identify the best predictors of melanoma using a multivariate analysis and to explore eventual new dermoscopic criteria for nail melanoma diagnosis. In this retrospective observational study, 82 histopathologically diagnosed, acquired nail pigmented bands were collected and examined. All variables were included in the analysis and examined as possible predictors of nail melanoma. Both univariate and multivariable analyses have been performed. Among 82 cases, 25 were diagnosed as nail melanoma and 57 as benign lesions (including 32 melanocytic nevi and 25 benign melanocytic hyperplasia). Melanoma cases were significantly associated with a width of the pigmented band higher than 2/3 of the nail plate, grey and black colours, irregularly pigmented lines, Hutchinson and micro-Hutchinson signs, and nail dystrophy. Granular pigmentation, a newly defined dermoscopic criterion, was found in 40% of melanomas and only in 3.51% of benign lesions. Dermoscopic examination of longitudinal melanonychia provides useful information that could help clinicians to improve melanoma recognition. © 2016 European Academy of Dermatology and Venereology.

Global strength assessment in oblique waves of a large gas carrier ship, based on a non-linear iterative method

NASA Astrophysics Data System (ADS)

Domnisoru, L.; Modiga, A.; Gasparotti, C.

2016-08-01

At the ship's design, the first step of the hull structural assessment is based on the longitudinal strength analysis, with head wave equivalent loads by the ships' classification societies’ rules. This paper presents an enhancement of the longitudinal strength analysis, considering the general case of the oblique quasi-static equivalent waves, based on the own non-linear iterative procedure and in-house program. The numerical approach is developed for the mono-hull ships, without restrictions on 3D-hull offset lines non-linearities, and involves three interlinked iterative cycles on floating, pitch and roll trim equilibrium conditions. Besides the ship-wave equilibrium parameters, the ship's girder wave induced loads are obtained. As numerical study case we have considered a large LPG liquefied petroleum gas carrier. The numerical results of the large LPG are compared with the statistical design values from several ships' classification societies’ rules. This study makes possible to obtain the oblique wave conditions that are inducing the maximum loads into the large LPG ship's girder. The numerical results of this study are pointing out that the non-linear iterative approach is necessary for the computation of the extreme loads induced by the oblique waves, ensuring better accuracy of the large LPG ship's longitudinal strength assessment.

Occurrence of Multiple Sclerosis After Drug Exposure: Insights From Evidence Mapping.

PubMed

Antonazzo, Ippazio Cosimo; Raschi, Emanuel; Vignatelli, Luca; Baldin, Elisa; Riise, Trond; D'Alessandro, Roberto; De Ponti, Fabrizio; Poluzzi, Elisabetta

2017-09-01

The role of drugs in the occurrence of multiple sclerosis (MS) is perceived to be insufficiently investigated. The aim of this study was to map and assess the evidence on MS occurrence after drug exposure, in order to identify possible signals of causal association. A search strategy was performed in MEDLINE and Embase as of July 2016; references consistent with the aim of the study were analysed to extract relevant measures of causal association between drugs and MS. The Newcastle-Ottawa Scale and appropriate guidelines from the International Society for Pharmacoepidemiology (ISPE) and the International Society of Pharmacovigilance (ISoP) were used to assess the quality of included studies. After screening 832 articles, 58 were selected (of which 14 were found by checking the reference lists of reviews): 30 case reports and case series, 24 longitudinal studies and four randomized controlled trials. Seven longitudinal studies had good (at least 7 out of 9) quality scores, whereas case reports/case series presented several limitations. Half of included articles focused on immunomodulatory drugs (etanercept, infliximab and adalimumab), especially in case reports/series, suggesting an association with MS occurrence. Contraceptives and antibacterials were investigated in some population-based studies, without definite results. A heterogeneous pharmacological profile of identified classes emerged. Low strength of evidence and conflicting results highlighted the difficulties in addressing the possible contribution of drugs in MS occurrence. Methodological advances are needed, especially to control the confounding role of underlying disease for specific drug classes.

Application of the Levenshtein Distance Metric for the Construction of Longitudinal Data Files

ERIC Educational Resources Information Center

Doran, Harold C.; van Wamelen, Paul B.

2010-01-01

The analysis of longitudinal data in education is becoming more prevalent given the nature of testing systems constructed for No Child Left Behind Act (NCLB). However, constructing the longitudinal data files remains a significant challenge. Students move into new schools, but in many cases the unique identifiers (ID) that should remain constant…

Mixed models approaches for joint modeling of different types of responses.

PubMed

Ivanova, Anna; Molenberghs, Geert; Verbeke, Geert

2016-01-01

In many biomedical studies, one jointly collects longitudinal continuous, binary, and survival outcomes, possibly with some observations missing. Random-effects models, sometimes called shared-parameter models or frailty models, received a lot of attention. In such models, the corresponding variance components can be employed to capture the association between the various sequences. In some cases, random effects are considered common to various sequences, perhaps up to a scaling factor; in others, there are different but correlated random effects. Even though a variety of data types has been considered in the literature, less attention has been devoted to ordinal data. For univariate longitudinal or hierarchical data, the proportional odds mixed model (POMM) is an instance of the generalized linear mixed model (GLMM; Breslow and Clayton, 1993). Ordinal data are conveniently replaced by a parsimonious set of dummies, which in the longitudinal setting leads to a repeated set of dummies. When ordinal longitudinal data are part of a joint model, the complexity increases further. This is the setting considered in this paper. We formulate a random-effects based model that, in addition, allows for overdispersion. Using two case studies, it is shown that the combination of random effects to capture association with further correction for overdispersion can improve the model's fit considerably and that the resulting models allow to answer research questions that could not be addressed otherwise. Parameters can be estimated in a fairly straightforward way, using the SAS procedure NLMIXED.

L2 Learners' Informal Online Interactions in Social Network Communities

ERIC Educational Resources Information Center

Malerba, Maria-Luisa

2012-01-01

This paper reports on a study on the use of social network sites (SNSs) designed for L2 learning, such as "Livemocha" and "Busuu", where learners autonomously seek opportunities for authentic interaction in spontaneous ways. The study consists in a longitudinal multiple case study approach to investigate learners' informal…

"Crazyghettosmart": A Case Study in Latina Identities

ERIC Educational Resources Information Center

Vetter, Amy M.; Fairbanks, Colleen; Ariail, Mary

2011-01-01

Drawing from recent scholarship that examines schooling and the shifting terrain of youth identities, this study examines the identity constructions of Jessica, a Latina high school student. Our portrait of Jessica is part of a larger longitudinal study in which the middle and high school experiences of three Latinas, including Jessica, were…

NATURAL ATTENUATION OF MTBE

EPA Science Inventory

For the case studies, the MTBE, TBA, and BTEX plume will be studied in a longitudinal transect along the center-line of the plume, and at least two transects perpendicular to ground water flow. Water samples will be analyzed for the concentration of MTBE, TBA, BTEX, methane, sulf...

An airport wind shear detection and warning system using Doppler radar: A feasibility study

NASA Technical Reports Server (NTRS)

Mccarthy, J.; Blick, E. F.; Elmore, K. L.

1981-01-01

A feasibility study was conducted to determine whether ground based Doppler radar could measure the wind along the path of an approaching aircraft with sufficient accuracy to predict aircraft performance. Forty-three PAR approaches were conducted, with 16 examined in detail. In each, Doppler derived longitudinal winds were compared to aircraft measured winds; in approximately 75 percent of the cases, the Doppler and aircraft winds were in acceptable agreement. In the remaining cases, errors may have been due to a lack of Doppler resolution, a lack of co-location of the two sampling volumes, the presence of eddy or vortex like disturbances within the pulse volume, or the presence of point targets in antenna side lobes. It was further concluded that shrouding techniques would have reduced the side lobe problem. A ground based Doppler radar operating in the optically clear air, provides the appropriate longitudinal winds along an aircraft's intended flight path.

Building emotional resilience over 14 sessions of emotion focused therapy: Micro-longitudinal analyses of productive emotional patterns.

PubMed

Pascual-Leone, A; Yeryomenko, N; Sawashima, T; Warwar, S

2017-05-04

Pascual-Leone and Greenberg's sequential model of emotional processing has been used to explore process in over 24 studies. This line of research shows emotional processing in good psychotherapy often follows a sequential order, supporting a saw-toothed pattern of change within individual sessions (progressing "2-steps-forward, 1-step-back"). However, one cannot assume that local in-session patterns are scalable across an entire course of therapy. Thus, the primary objective of this exploratory study was to consider how the sequential patterns identified by Pascual-Leone, may apply across entire courses of treatment. Intensive emotion coding in two separate single-case designs were submitted for quantitative analyses of longitudinal patterns. Comprehensive coding in these cases involved recording observations for every emotional event in an entire course of treatment (using the Classification of Affective-Meaning States), which were then treated as a 9-point ordinal scale. Applying multilevel modeling to each of the two cases showed significant patterns of change over a large number of sessions, and those patterns were either nested at the within-session level or observed at the broader session-by-session level of change. Examining successful treatment cases showed several theoretically coherent kinds of temporal patterns, although not always in the same case. Clinical or methodological significance of this article: This is the first paper to demonstrate systematic temporal patterns of emotion over the course of an entire treatment. (1) The study offers a proof of concept that longitudinal patterns in the micro-processes of emotion can be objectively derived and quantified. (2) It also shows that patterns in emotion may be identified on the within-session level, as well as the session-by-session level of analysis. (3) Finally, observed processes over time support the ordered pattern of emotional states hypothesized in Pascual-Leone and Greenberg's ( 2007 ) model of emotional processing.

Transition from convective to absolute Raman instability via the longitudinal relativistic effect by using Vlasov-Maxwell simulations

NASA Astrophysics Data System (ADS)

Wang, Q.; Liu, Z. J.; Zheng, C. Y.; Xiao, C. Z.; Feng, Q. S.; Zhang, H. C.; He, X. T.

2018-01-01

The longitudinal relativistic effect on stimulated Raman backscattering (SRBS) is investigated by using one-dimensional (1D) Vlasov-Maxwell simulations. Using a short backscattered light seed pulse with a very small amplitude, the linear gain spectra of SRBS in the strongly convective regime is presented by combining the relativistic and non-relativistic 1D Vlasov-Maxwell simulations, which is in agreement with the steady-state linear theory. More interestingly, by considering transition from convective to absolute instability due to electron trapping, we successfully predict the critical duration of the seed which can just trigger the kinetic inflation of the excited SRBS after the seed leaves the simulation box. The critical duration in the relativistic case is much shorter than that in the nonrelativistic case, which indicates that the kinetic inflation more easily occurs in the relativistic case than in the nonrelativistic case. In the weakly convective regime, the transition from convective to absolute instability for SRBS can directly occur in the linear regime due to the longitudinal relativistic modification. For the same pump, our simulations first demonstrate that the SRBS excited by a short and small seed pulse is a convective instability in the nonrelativistic case but becomes an absolute instability due to the decrease of the linear Landau damping from the longitudinal relativistic modification in the relativistic case. In more detail, the growth rate of the backscattered light is also in excellent agreement with theoretical prediction.

Comparison of Expert-Based and Empirical Evaluation Methodologies in the Case of a CBL Environment: The ''Orestis'' Experience

ERIC Educational Resources Information Center

Karoulis, Athanasis; Demetriadis, Stavros; Pombortsis, Andreas

2006-01-01

This paper compares several interface evaluation methods applied in the case of a computer based learning (CBL) environment, during a longitudinal study performed in three European countries, Greece, Germany, and Holland, and within the framework of an EC funded Leonardo da Vinci program. The paper firstly considers the particularities of the CBL…

Effects of correlations between particle longitudinal positions and transverse plane on bunch length measurement: a case study on GBS electron LINAC at ELI-NP

NASA Astrophysics Data System (ADS)

Sabato, L.; Arpaia, P.; Cianchi, A.; Liccardo, A.; Mostacci, A.; Palumbo, L.; Variola, A.

2018-02-01

In high-brightness LINear ACcelerators (LINACs), electron bunch length can be measured indirectly by a radio frequency deflector (RFD). In this paper, the accuracy loss arising from non-negligible correlations between particle longitudinal positions and the transverse plane (in particular the vertical one) at RFD entrance is analytically assessed. Theoretical predictions are compared with simulation results, obtained by means of ELEctron Generation ANd Tracking (ELEGANT) code, in the case study of the gamma beam system (GBS) at the extreme light infrastructure—nuclear physics (ELI-NP). In particular, the relative error affecting the bunch length measurement, for bunches characterized by both energy chirp and fixed correlation coefficients between longitudinal particle positions and the vertical plane, is reported. Moreover, the relative error versus the correlation coefficients is shown for fixed RFD phase 0 rad and π rad. The relationship between relative error and correlations factors can help the decision of using the bunch length measurement technique with one or two vertical spot size measurements in order to cancel the correlations contribution. In the case of the GBS electron LINAC, the misalignment of one of the quadrupoles before the RFD between  -2 mm and 2 mm leads to a relative error less than 5%. The misalignment of the first C-band accelerating section between  -2 mm and 2 mm could lead to a relative error up to 10%.

Brain MRI volumetry in a single patient with mild traumatic brain injury.

PubMed

Ross, David E; Castelvecchi, Cody; Ochs, Alfred L

2013-01-01

This letter to the editor describes the case of a 42 year old man with mild traumatic brain injury and multiple neuropsychiatric symptoms which persisted for a few years after the injury. Initial CT scans and MRI scans of the brain showed no signs of atrophy. Brain volume was measured using NeuroQuant®, an FDA-approved, commercially available software method. Volumetric cross-sectional (one point in time) analysis also showed no atrophy. However, volumetric longitudinal (two points in time) analysis showed progressive atrophy in several brain regions. This case illustrated in a single patient the principle discovered in multiple previous group studies, namely that the longitudinal design is more powerful than the cross-sectional design for finding atrophy in patients with traumatic brain injury.

Programs of Study: A Cross-Study Examination of Programs in Three States

ERIC Educational Resources Information Center

Stringfield, Sam; Shumer, Robert; Stipanovic, Natalie; Murphy, Nora

2013-01-01

The National Research Center on Career and Technical Education has supported four studies on one of the major components of Perkins legislation: programs of study. In this article, we present qualitative data linking the research center's longitudinal projects based on programs of study, via a one-time cross-case study of sites deemed highly…

Quantifying the impact of the longitudinal dispersion coefficient parameter uncertainty on the physical transport processes in rivers

NASA Astrophysics Data System (ADS)

Camacho Suarez, V. V.; Shucksmith, J.; Schellart, A.

2016-12-01

Analytical and numerical models can be used to represent the advection-dispersion processes governing the transport of pollutants in rivers (Fan et al., 2015; Van Genuchten et al., 2013). Simplifications, assumptions and parameter estimations in these models result in various uncertainties within the modelling process and estimations of pollutant concentrations. In this study, we explore both: 1) the structural uncertainty due to the one dimensional simplification of the Advection Dispersion Equation (ADE) and 2) the parameter uncertainty due to the semi empirical estimation of the longitudinal dispersion coefficient. The relative significance of these uncertainties has not previously been examined. By analysing both the relative structural uncertainty of analytical solutions of the ADE, and the parameter uncertainty due to the longitudinal dispersion coefficient via a Monte Carlo analysis, an evaluation of the dominant uncertainties for a case study in the river Chillan, Chile is presented over a range of spatial scales.

Key trends in environmental advertising across 30 years in National Geographic magazine.

PubMed

Ahern, Lee; Bortree, Denise Sevick; Smith, Alexandra Nutter

2013-05-01

This longitudinal retrospective case study describes the sponsors, ad types, frames and message factors in green advertising over three decades in National Geographic magazine, the bellwether nature publication in the USA. In addition to providing a clearer picture of the extent and nature of environmental strategic messaging over three decades, results provide empirical support for theoretical relationships between the level of green advertising and economic indicators. After providing historical and theoretical context, detailed results are presented for both overall and longitudinal analysis. Limitations and implications for future research are discussed.

Three-dimensional envelope instability in periodic focusing channels

NASA Astrophysics Data System (ADS)

Qiang, Ji

2018-03-01

The space-charge driven envelope instability can be of great danger in high intensity accelerators and was studied using a two-dimensional (2D) envelope model and three-dimensional (3D) macroparticle simulations before. In this paper, we study the instability for a bunched beam using a three-dimensional envelope model in a periodic solenoid and radio-frequency (rf) focusing channel and a periodic quadrupole and rf focusing channel. This study shows that when the transverse zero current phase advance is below 90 ° , the beam envelope can still become unstable if the longitudinal zero current phase advance is beyond 90 ° . For the transverse zero current phase advance beyond 90 ° , the instability stopband width becomes larger with the increase of the longitudinal focusing strength and even shows different structure from the 2D case when the longitudinal zero current phase advance is beyond 90 ° . Breaking the symmetry of two longitudinal focusing rf cavities and the symmetry between the horizontal focusing and the vertical focusing in the transverse plane in the periodic quadrupole and rf channel makes the instability stopband broader. This suggests that a more symmetric accelerator lattice design might help reduce the range of the envelope instability in parameter space.

Accuracy of malaria rapid diagnostic tests in community studies and their impact on treatment of malaria in an area with declining malaria burden in north-eastern Tanzania.

PubMed

Ishengoma, Deus S; Francis, Filbert; Mmbando, Bruno P; Lusingu, John P A; Magistrado, Pamela; Alifrangis, Michael; Theander, Thor G; Bygbjerg, Ib C; Lemnge, Martha M

2011-06-26

Despite some problems related to accuracy and applicability of malaria rapid diagnostic tests (RDTs), they are currently the best option in areas with limited laboratory services for improving case management through parasitological diagnosis and reducing over-treatment. This study was conducted in areas with declining malaria burden to assess; 1) the accuracy of RDTs when used at different community settings, 2) the impact of using RDTs on anti-malarial dispensing by community-owned resource persons (CORPs) and 3) adherence of CORPs to treatment guidelines by providing treatment based on RDT results. Data were obtained from: 1) a longitudinal study of passive case detection of fevers using CORPs in six villages in Korogwe; and 2) cross-sectional surveys (CSS) in six villages of Korogwe and Muheza districts, north-eastern, Tanzania. Performance of RDTs was compared with microscopy as a gold standard, and factors affecting their accuracy were explored using a multivariate logistic regression model. Overall sensitivity and specificity of RDTs in the longitudinal study (of 23,793 febrile cases; 18,154 with microscopy and RDTs results) were 88.6% and 88.2%, respectively. In the CSS, the sensitivity was significantly lower (63.4%; χ2=367.7, p<0.001), while the specificity was significantly higher (94.3%; χ2=143.1, p<0.001) when compared to the longitudinal study. As determinants of sensitivity of RDTs in both studies, parasite density of<200 asexual parasites/μl was significantly associated with high risk of false negative RDTs (OR≥16.60, p<0.001), while the risk of false negative test was significantly lower among cases with fever (axillary temperature ≥37.5 °C) (OR≤0.63, p≤0.027). The risk of false positive RDT (as a determinant of specificity) was significantly higher in cases with fever compared to afebrile cases (OR≥2.40, p<0.001). Using RDTs reduced anti-malarials dispensing from 98.9% to 32.1% in cases aged ≥5 years. Although RDTs had low sensitivity and specificity, which varied widely depending on fever and parasite density, using RDTs reduced over-treatment with anti-malarials significantly. Thus, with declining malaria prevalence, RDTs will potentially identify majority of febrile cases with parasites and lead to improved management of malaria and non-malaria fevers. © 2011 Ishengoma et al; licensee BioMed Central Ltd.

Accuracy of malaria rapid diagnostic tests in community studies and their impact on treatment of malaria in an area with declining malaria burden in north-eastern Tanzania

PubMed Central

2011-01-01

Background Despite some problems related to accuracy and applicability of malaria rapid diagnostic tests (RDTs), they are currently the best option in areas with limited laboratory services for improving case management through parasitological diagnosis and reducing over-treatment. This study was conducted in areas with declining malaria burden to assess; 1) the accuracy of RDTs when used at different community settings, 2) the impact of using RDTs on anti-malarial dispensing by community-owned resource persons (CORPs) and 3) adherence of CORPs to treatment guidelines by providing treatment based on RDT results. Methods Data were obtained from: 1) a longitudinal study of passive case detection of fevers using CORPs in six villages in Korogwe; and 2) cross-sectional surveys (CSS) in six villages of Korogwe and Muheza districts, north-eastern, Tanzania. Performance of RDTs was compared with microscopy as a gold standard, and factors affecting their accuracy were explored using a multivariate logistic regression model. Results Overall sensitivity and specificity of RDTs in the longitudinal study (of 23,793 febrile cases; 18,154 with microscopy and RDTs results) were 88.6% and 88.2%, respectively. In the CSS, the sensitivity was significantly lower (63.4%; χ2 = 367.7, p < 0.001), while the specificity was significantly higher (94.3%; χ2 = 143.1, p < 0.001) when compared to the longitudinal study. As determinants of sensitivity of RDTs in both studies, parasite density of < 200 asexual parasites/μl was significantly associated with high risk of false negative RDTs (OR≥16.60, p < 0.001), while the risk of false negative test was significantly lower among cases with fever (axillary temperature ≥37.5°C) (OR ≤ 0.63, p ≤ 0.027). The risk of false positive RDT (as a determinant of specificity) was significantly higher in cases with fever compared to afebrile cases (OR≥2.40, p < 0.001). Using RDTs reduced anti-malarials dispensing from 98.9% to 32.1% in cases aged ≥5 years. Conclusion Although RDTs had low sensitivity and specificity, which varied widely depending on fever and parasite density, using RDTs reduced over-treatment with anti-malarials significantly. Thus, with declining malaria prevalence, RDTs will potentially identify majority of febrile cases with parasites and lead to improved management of malaria and non-malaria fevers. PMID:21703016

(Re)Anchored, Video-Centered Engagement: The Transferability of Preservice Training to Practice

ERIC Educational Resources Information Center

Dickinson, Gail; Summers, Emily J.

2010-01-01

This longitudinal study tracks primary participants over 3 years from their last year of university preservice teaching training through their second year of in-service teaching via surveys, interviews, and teaching observations. The study employs a descriptive case study design to examine the transfer of preservice content, pedagogy, and video…

Research, Practice, and Policy Connections: The Artplay Case Study

ERIC Educational Resources Information Center

Brown, Robert; Jeanneret, Neryl

2017-01-01

This article explores the nexus between arts-based research, theory, practice, and policy. It does so through reference to a longitudinal study of ArtPlay, a unique Australian community arts center that offers artist-led workshops involving young people aged 3-13 years. The ethnographic and action research study investigated how children responded…

Chinese Business Students' Changes in Beliefs and Strategy Use in a Constructively Aligned PBL Course

ERIC Educational Resources Information Center

Zhao, Ke; Zhang, Jie; Du, Xiangyun

2017-01-01

This study adopted a longitudinal retrospective case study approach to investigate Chinese business students' transitional learning experience in a problem-based learning (PBL) course with innovative assessment practices. The study focused on students' beliefs and strategy use in a constructively aligned PBL course for business communication.…

Risk of malignancy with systemic psoriasis treatment in the Psoriasis Longitudinal Assessment Registry.

PubMed

Fiorentino, David; Ho, Vincent; Lebwohl, Mark G; Leite, Luiz; Hopkins, Lori; Galindo, Claudia; Goyal, Kavitha; Langholff, Wayne; Fakharzadeh, Steven; Srivastava, Bhaskar; Langley, Richard G

2017-11-01

The effect of systemic therapy on malignancy risk among patients with psoriasis is not fully understood. Evaluate the impact of systemic treatment on malignancy risk among patients with psoriasis in the Psoriasis Longitudinal Assessment and Registry (PSOLAR). Nested case-control analyses were performed among patients with no history of malignancy. Cases were defined as first malignancy (other than nonmelanoma skin cancer) in the Psoriasis Longitudinal Assessment and Registry, and controls were matched by age, sex, geographic region, and time on registry. Study therapies included methotrexate, ustekinumab, and tumor necrosis factor-α (TNF-α) inhibitors. Exposure was defined as 1 or more doses of study therapy within 12 months of malignancy onset and further stratified by duration of therapy. Multivariate conditional logistic regression, adjusted for potential confounders, was used to estimate odds ratios of malignancies associated with therapy. Among 12,090 patients, 252 malignancy cases were identified and 1008 controls were matched. Treatment with methotrexate or ustekinumab for more than 0 months to less than 3 months, 3 months to less than 12 months, or 12 months or longer was not associated with increased malignancy risk versus no exposure. Longer-term (≥12 months) (odds ratio, 1.54; 95% confidence interval, 1.10-2.15; P = .01), but not shorter-term treatment, with a TNF-α inhibitor was associated with increased malignancy risk. Cases and controls could belong to 1 or more therapy categories. Long-term (≥12 months) treatment with a TNF-α inhibitor, but not methotrexate and ustekinumab, may increase risk for malignancy in patients with psoriasis. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Long-Term Teacher Orchestration of Technology-Mediated Collaborative Inquiry

ERIC Educational Resources Information Center

Viilo, Marjut; Seitamaa-Hakkarainen, Pirita; Hakkarainen, Kai

2018-01-01

This explorative case study longitudinally examines teacher orchestration of an inquiry learning process in a technology-enhanced elementary classroom. A 13-month investigative study on cultural artifacts was conducted on 32 fourth grade students who progressed to the fifth grade during the project. The activities were mediated and documented…

Styles of Career Decision-Making

ERIC Educational Resources Information Center

Bimrose, Jenny; Barnes, Sally-Anne

2007-01-01

Distinctive styles of client decision-making have emerged from case study research into the effectiveness of career guidance. This paper explores some findings from the third year of a longitudinal study currently underway in England, which relate to the ways clients approach transition points in their careers and make the decisions that move them…

Learning from Profiles of the Special Needs Gifted

ERIC Educational Resources Information Center

Swanson, Julie Dingle; Van Tassel-Baska, Joyce; Feng, Annie; Chandler, Kimberley

2007-01-01

Through a longitudinal study focused on identification policy that is inclusive of underrepresented gifted students (Van Tassel-Baska & Feng, 2003; Van Tassel-Baska, Feng, & deBrux, under review; Van Tassel-Baska, Feng, & Evans, in press; Van Tassel-Baska, Johnson, & Avery, 2002), a team of researchers developed case studies of special needs…

Intercultural Identity and Intercultural Experiences of American Students in China

ERIC Educational Resources Information Center

Tian, Mei; Lowe, John Anthony

2014-01-01

The number of international students in China is increasing rapidly, but their experiences in China remain largely unknown. This article reports an intensive longitudinal multiple case study that explores eight American students' intercultural experiences and the impacts of such experiences on individual identity during their study in a Chinese…

Understanding Successful Sandwich Placements: A Bourdieusian Approach

ERIC Educational Resources Information Center

Clark, Martyn; Zukas, Miriam

2016-01-01

Sandwich placements and other integrated work and study schemes are increasingly advocated as a key means by which universities can promote students' employability. However, there is little understanding of how successful placements work in terms of facilitating learning and development. Drawing on three longitudinal case studies of students who…

Languaging as Competencing: Considering Language Learning as Enactment

ERIC Educational Resources Information Center

Hellermann, John

2018-01-01

The terms "interactional competence" and "learning" are discussed in the context of recent research in the areas of cognitive science and ethnomethodological conversation analysis studies of language learning. Two data excerpts from a longitudinal case study of a beginning learner of English are presented to illustrate (1) the…

Increased risk for an atypical autism diagnosis following Thimerosal-containing vaccine exposure in the United States: A prospective longitudinal case-control study in the Vaccine Safety Datalink.

PubMed

Geier, David A; Kern, Janet K; Geier, Mark R

2017-07-01

Thimerosal is an organic-mercury (Hg)-containing compound (49.55% Hg by weight) historically added to many multi-dose vials of vaccine as a preservative and still added to some vaccines today. Concerns about the toxic effects from Thimerosal-containing childhood vaccines and the risk of an atypical autism diagnosis were evaluated in this study. A hypothesis-testing, prospective longitudinal, case-control study assessed exposure to Hg from Thimerosal-containing hepatitis B vaccines (TM-HepB) among cases diagnosed with atypical autism (n=164) and controls (n=15,216). Automated medical records for subjects born from 1991 to 2000 and continuously enrolled in the Vaccine Safety Datalink (VSD) database were examined. Cases diagnosed with atypical autism were statistically significantly more likely to have received greater overall and dose-dependent exposures to Hg from TM-HepB vaccines administered within the first month of life, first two months of life, and first six months of life than the controls. Similar phenomena were observed when cases and controls were separated by gender. Routine childhood vaccination is an important public health tool to reduce infectious diseases. The present study provides important epidemiological evidence significantly associating increasing Hg exposure from Thimerosal-containing childhood vaccines and the subsequent risk of atypical autism diagnosis, and suggests that Thimerosal should be eliminated from vaccines. Copyright © 2017 Elsevier GmbH. All rights reserved.

Verbal Memory Declines More Rapidly with Age in HIV Infected versus Uninfected Adults

PubMed Central

Seider, Talia R.; Luo, Xi; Gongvatana, Assawin; Devlin, Kathryn N.; de la Monte, Suzanne M.; Chasman, Jesse D.; Yan, Peisi; Tashima, Karen T.; Navia, Bradford; Cohen, Ronald A.

2015-01-01

Objectives In the current era of effective antiretroviral treatment, the number of older adults living with HIV is rapidly increasing. This study investigated the combined influence of age and HIV infection on longitudinal changes in verbal and visuospatial learning and memory. Methods In this longitudinal, case-control design, 54 HIV seropositive and 30 seronegative individuals aged 40–74 received neurocognitive assessments at baseline visits and again one year later. Assessment included tests of verbal and visuospatial learning and memory. Linear regression was used to predict baseline performance and longitudinal change on each test using HIV serostatus, age, and their interaction as predictors. MANOVA was used to assess the effects of these predictors on overall baseline performance and overall longitudinal change. Results The interaction of HIV and age significantly predicted longitudinal change in verbal memory performance, as did HIV status, indicating that although the seropositive group declined more than the seronegative group overall, the rate of decline depended on age such that greater age was associated with a greater decline in this group. The regression models for visuospatial learning and memory were significant at baseline, but did not predict change over time. HIV status significantly predicted overall baseline performance and overall longitudinal change. Conclusions This is the first longitudinal study focused on the effects of age and HIV on memory. Findings suggest that age and HIV interact to produce larger declines in verbal memory over time. Further research is needed to gain a greater understanding of the effects of HIV on the aging brain. PMID:24645772

Longitudinal Deformation of Distal Edge in a New-Generation Stent Caused by Guidewire Entrapment

PubMed Central

Taleb, Adam; Parikh, Gaurav

2018-01-01

Longitudinal stent deformation, described in some older stent geometries, prompted design modifications such as reinforcing struts on the proximal end. However, distal edges of stents—also subject to longitudinal force—have not been reinforced. We report a case of guidewire entrapment that deformed the distal edge of a new-generation stent during percutaneous coronary intervention, and we describe our efforts to restore the stent to its initial length. This case highlights the risk of manipulating equipment beyond the position of a newly deployed stent, the ongoing potential for deformation of distal edges in newer stent platforms, and the advisability of treating distal lesions before proximal ones. PMID:29556153

Predicting changes in sleep complaints from baseline values and changes in work demands, work control, and work preoccupation--the WOLF-project.

PubMed

Åkerstedt, Torbjörn; Nordin, Maria; Alfredsson, Lars; Westerholm, Peter; Kecklund, Göran

2012-01-01

Stress as a cause of disturbed sleep is often taken for granted, but the longitudinal evidence is limited. The aim of this study was to evaluate new cases of poor sleep as a function of changes in reported work demands, work control, and work preoccupation. Longitudinal study of change with measures occurring twice within a 5-year interval during a period when the prevalence of impaired sleep was increasing in Sweden. The sample of companies was taken from northern Sweden (Norrland) and included 3637 individuals from the "WOLF Norrland" longitudinal cohort, collected through company health services. During the measurement period, 16% of those studied developed new cases of impaired sleep. Logistic regressions adjusted for demographics, work environment factors, and disturbed sleep at T1 period one showed a significant increase in new cases for high work demands and high work preoccupation (OR=1.37; Ci=1.09-1.72 and OR=1.80; CI=1.42-2.28, respectively). The analysis of change in the predictors showed effects of a change from low to high work demands (OR=1.39; Ci=1.00-1.95) on new cases of impaired sleep. Consistent high work demands (high at both points) showed a similar increase (OR=1.49; Ci=1.06-2.11) but no effect was seen for reduced demands. Change in work preoccupation yielded stronger effects with OR=2.47 (1.78-2.47) for increased work preoccupation and OR=3.79 (2.70-5.31) for consistent high work preoccupation. Also, a reduction in work preoccupation was associated with a reduction in new cases of disturbed sleep. Control at work was not related to sleep. Stratification with respect to gender mainly led to fewer significant results (particularly for women) due to larger confidence intervals. It was concluded that self-reported work preoccupation predicts subsequent impairment of sleep and that increased preoccupation is associated with new cases of impaired sleep. Similar, but weaker, results were obtained for work demands. Copyright © 2011 Elsevier B.V. All rights reserved.

Vitamin D intake during the first 4 years and onset of asthma by age 5: A nested case-control study.

PubMed

Nwaru, Bright I; Hadkhale, Kishor; Hämäläinen, Niina; Takkinen, Hanna-Mari; Ahonen, Suvi; Ilonen, Jorma; Toppari, Jorma; Niemelä, Onni; Haapala, Anna-Maija; Veijola, Riitta; Knip, Mikael; Virtanen, Suvi M

2017-11-01

Early-life vitamin D intake has been linked to asthma risk in childhood, but the role of longitudinal vitamin D exposure has not been previously evaluated. We investigated the association between vitamin D intake during the first 4 years of life and asthma risk by age 5. Within a Finnish population-based birth cohort, 182 incident asthma cases were matched to 728 controls on sex, genetic risk for type 1 diabetes, delivery hospital, and time of birth. Vitamin D intake was assessed by age-specific 3 day food records. Parents completed a validated version of the International Study of Asthma and Allergies in Childhood questionnaire at 5 years. At 3 months, supplements were the main source of vitamin D intake; intake from foods increased from 3 months on, mainly from fortified milk products. Vitamin D intake at each specific age was associated with an increased risk of any asthma, atopic, and non-atopic asthma, but only intake at 1 and 2 years was statistically significantly associated with asthma. Longitudinal vitamin D intake was associated with an increased risk of asthma (OR 1.24; 95%CI 1.00-1.53). Increased vitamin D intake in childhood, particularly intake at 1 and 2 years of age, may increase risk of childhood asthma. This might reflect a true effect or residual confounding by lifestyle or environmental factors. Repeated assessment of vitamin D intake allowed evaluation of the longitudinal and age-dependent impact of vitamin D on the risk of asthma. Further longitudinal studies are required to confirm or question these findings. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

Tea Consumption Reduces the Incidence of Neurocognitive Disorders: Findings from the Singapore Longitudinal Aging Study.

PubMed

Feng, L; Chong, M-S; Lim, W-S; Gao, Q; Nyunt, M S; Lee, T-S; Collinson, S L; Tsoi, T; Kua, E-H; Ng, T-P

2016-01-01

To examine the relationships between tea consumption habits and incident neurocognitive disorders (NCD) and explore potential effect modification by gender and the apolipoprotein E (APOE) genotype. Population-based longitudinal study. The Singapore Longitudinal Aging Study (SLAS). 957 community-living Chinese elderly who were cognitively intact at baseline. We collected tea consumption information at baseline from 2003 to 2005 and ascertained incident cases of neurocognitive disorders (NCD) from 2006 to 2010. Odds ratio (OR) of association were calculated in logistic regression models that adjusted for potential confounders. A total of 72 incident NCD cases were identified from the cohort. Tea intake was associated with lower risk of incident NCD, independent of other risk factors. Reduced NCD risk was observed for both green tea (OR=0.43) and black/oolong tea (OR=0.53) and appeared to be influenced by the changing of tea consumption habit at follow-up. Using consistent non-tea consumers as the reference, only consistent tea consumers had reduced risk of NCD (OR=0.39). Stratified analyses indicated that tea consumption was associated with reduced risk of NCD among females (OR=0.32) and APOE ε4 carriers (OR=0.14) but not males and non APOE ε4 carriers. Regular tea consumption was associated with lower risk of neurocognitive disorders among Chinese elderly. Gender and genetic factors could possibly modulate this association.

The impact of sedimentary anisotropy on solute mixing in stacked scour-pool structures

NASA Astrophysics Data System (ADS)

Bennett, Jeremy P.; Haslauer, Claus P.; Cirpka, Olaf A.

2017-04-01

The spatial variability of hydraulic conductivity is known to have a strong impact on solute spreading and mixing. In most investigations, its local anisotropy has been neglected. Recent studies have shown that spatially varying orientation in sedimentary anisotropy can lead to twisting flow enhancing transverse mixing, but most of these studies used geologically implausible geometries. We use an object-based approach to generate stacked scour-pool structures with either isotropic or anisotropic filling which are typically reported in glacial outwash deposits. We analyze how spatially variable isotropic conductivity and variation of internal anisotropy in these features impacts transverse plume deformation and both longitudinal and transverse spreading and mixing. In five test cases, either the scalar values of conductivity or the spatial orientation of its anisotropy is varied between the scour-pool structures. Based on 100 random configurations, we compare the variability of velocity components, stretching and folding metrics, advective travel-time distributions, one and two-particle statistics in advective-dispersive transport, and the flux-related dilution indices for steady state advective-dispersive transport among the five test cases. Variation in the orientation of internal anisotropy causes strong variability in the lateral velocity components, which leads to deformation in transverse directions and enhances transverse mixing, whereas it hardly affects the variability of the longitudinal velocity component and thus longitudinal spreading and mixing. The latter is controlled by the spatial variability in the scalar values of hydraulic conductivity. Our results demonstrate that sedimentary anisotropy is important for transverse mixing, whereas it may be neglected when considering longitudinal spreading and mixing.

Deadlines at work and sleep quality. Cross-sectional and longitudinal findings among Danish knowledge workers.

PubMed

Rugulies, Reiner; Martin, Marie H T; Garde, Anne Helene; Persson, Roger; Albertsen, Karen

2012-03-01

Exposure to deadlines at work is increasing in several countries and may affect health. We aimed to investigate cross-sectional and longitudinal associations between frequency of difficult deadlines at work and sleep quality. Study participants were knowledge workers, drawn from a representative sample of Danish employees who responded to a baseline questionnaire in 2006 (n = 363) and a follow-up questionnaire in 2007 (n = 302). Frequency of difficult deadlines was measured by self-report and categorized into low, intermediate, and high. Sleep quality was measured with a Total Sleep Quality Score and two indexes (Awakening Index and Disturbed Sleep Index) derived from the Karolinska Sleep Questionnaire. Analyses on the association between frequency of deadlines and sleep quality scores were conducted with multiple linear regression models, adjusted for potential confounders. In addition, we used multiple logistic regression models to analyze whether frequency of deadlines at baseline predicted caseness of sleep problems at follow-up among participants free of sleep problems at baseline. Frequent deadlines were cross-sectionally and longitudinally associated with poorer sleep quality on all three sleep quality measures. Associations in the longitudinal analyses were greatly attenuated when we adjusted for baseline sleep quality. The logistic regression analyses showed that frequent deadlines at baseline were associated with elevated odds ratios for caseness of sleep problems at follow-up, however, confidence intervals were wide in these analyses. Frequent deadlines at work were associated with poorer sleep quality among Danish knowledge workers. We recommend investigating the relation between deadlines and health endpoints in large-scale epidemiologic studies. Copyright © 2011 Wiley Periodicals, Inc.

Is 2D speckle tracking echocardiography useful for detecting and monitoring myocardial dysfunction in adult m.3243A>G carriers? - a retrospective pilot study.

PubMed

Koene, S; Timmermans, J; Weijers, G; de Laat, P; de Korte, C L; Smeitink, J A M; Janssen, M C H; Kapusta, L

2017-03-01

Cardiomyopathy is a common complication of mitochondrial disorders, associated with increased mortality. Two dimensional speckle tracking echocardiography (2DSTE) can be used to quantify myocardial deformation. Here, we aimed to determine the usefulness of 2DSTE in detecting and monitoring subtle changes in myocardial dysfunction in carriers of the 3243A>G mutation in mitochondrial DNA. In this retrospective pilot study, 30 symptomatic and asymptomatic carriers of the mitochondrial 3243A>G mutation of whom two subsequent echocardiograms were available were included. We measured longitudinal, circumferential and radial strain using 2DSTE. Results were compared to published reference values. Speckle tracking was feasible in 90 % of the patients for longitudinal strain. Circumferential and radial strain showed low face validity (low number of images with sufficient quality; suboptimal tracking) and were therefore rejected for further analysis. Global longitudinal strain showed good face validity, and was abnormal in 56-70 % (depending on reference values used) of the carriers (n = 27). Reproducibility was good (mean difference of 0.83 for inter- and 0.40 for intra-rater reproducibility; ICC 0.78 and 0.89, respectively). The difference between the first and the second measurement exceeded the measurement variance in 39 % of the cases (n = 23; feasibility of follow-up 77 %). Even in data collected as part of clinical care, two-dimensional strain echocardiography seems a feasible method to detect and monitor subtle changes in longitudinal myocardial deformation in adult carriers of the mitochondrial 3243A>G mutation. Based on our data and the reported accuracy of global longitudinal strain in other studies, we suggest the use of global longitudinal strain in a prospective follow-up or intervention study.

Assessment of Thermal Performance of Functionally Graded Materials in Longitudinal Fins

NASA Astrophysics Data System (ADS)

Hassanzadeh, R.; Bilgili, M.

2018-01-01

Assessment of the thermal characteristics of materials in heat exchangers with longitudinal fins is performed in the case where a conventional homogeneous material of a longitudinal fin is replaced by a functionally graded one, in which the fin material properties, such as the conductivity, are assumed to be graded as linear and power-law functions along the normal axis from the fin base to the fin tip. The resulting equations are calculated under two (Dirichlet and Neumann) boundary conditions. The equations are solved by an approximate analytical method with the use of the mean value theorem. The results show that the inhomogeneity index of a functionally graded material plays an important role for the thermal energy characteristics in such heat exchangers. In addition, it is observed that the use of such a material in longitudinal fins enhances the rate of heat transfer between the fin surface and surrounding fluid. Hopefully, the results obtained in the study will arouse interest of designers in heat exchange industry.

Multivariate longitudinal data analysis with censored and intermittent missing responses.

PubMed

Lin, Tsung-I; Lachos, Victor H; Wang, Wan-Lun

2018-05-08

The multivariate linear mixed model (MLMM) has emerged as an important analytical tool for longitudinal data with multiple outcomes. However, the analysis of multivariate longitudinal data could be complicated by the presence of censored measurements because of a detection limit of the assay in combination with unavoidable missing values arising when subjects miss some of their scheduled visits intermittently. This paper presents a generalization of the MLMM approach, called the MLMM-CM, for a joint analysis of the multivariate longitudinal data with censored and intermittent missing responses. A computationally feasible expectation maximization-based procedure is developed to carry out maximum likelihood estimation within the MLMM-CM framework. Moreover, the asymptotic standard errors of fixed effects are explicitly obtained via the information-based method. We illustrate our methodology by using simulated data and a case study from an AIDS clinical trial. Experimental results reveal that the proposed method is able to provide more satisfactory performance as compared with the traditional MLMM approach. Copyright © 2018 John Wiley & Sons, Ltd.

Delusional parasitosis on the psychiatric consultation service – a longitudinal perspective: case study

PubMed Central

Pansare, Neha; Tobia, Anthony; Bisen, Viwek; Kaufman, Kenneth R.

2017-01-01

Background Delusional parasitosis is infrequently seen in hospital-based consultation–liaison psychiatry. Aims Although there are many publications on delusional parasitosis, this report reviews a unique case that was diagnosed during a hospital admission and treated over the next 36 months. Method Case report and literature review. Results This case report describes a 65-year-old man who was diagnosed with delusional parasitosis during a hospital admission for congestive heart failure and acute kidney injury. A longitudinal description of the patient’s condition during the hospital stay and in the 36 months following discharge, during which time he was treated by a consultation psychiatrist, is provided. Conclusions In discussing the treatment of a challenging presentation, this case demonstrates the opportunity for consultation psychiatrists to initiate care in patients who might not otherwise seek psychiatric services. Patients with somatic delusions represent one group of patients who are unlikely to independently seek psychiatric treatment. Declaration of interest None. Copyright and usage © The Royal College of Psychiatrists 2017. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license. PMID:28630746

Generating qualitative data by design: the Australian Longitudinal Study on Women's Health qualitative data collection.

PubMed

Tavener, Meredith; Chojenta, Catherine; Loxton, Deborah

2016-07-15

Objectives and importance of study: The purpose of this study was to illustrate how qualitative free-text comments, collected within the context of a health survey, represent a rich data source for understanding specific phenomena. Work conducted with data from the Australian Longitudinal Study on Women's Health (ALSWH) was used to demonstrate the breadth and depth of qualitative information that can be collected. The ALSWH has been collecting data on women's health since 1996, and represents a unique opportunity for understanding lived experiences across the lifecourse. A multiple case study design was used to demonstrate the techniques that researchers have used to manage free-text qualitative comments collected by the ALSWH. Eleven projects conducted using free-text comments are discussed according to the method of analysis. These methods include coding (both inductively and deductively), longitudinal analyses and software-based analyses. This work shows that free-text comments are a data resource in their own right, and have the potential to provide rich and valuable information about a wide variety of topics.

Hydrodynamics and long range correlations

NASA Astrophysics Data System (ADS)

Bialas, A.; Zalewski, K.

2011-04-01

It is shown that the recently proposed method of studying the long-range correlations in multiparticle production can be effectively used to verify the hydrodynamic nature of the longitudinal expansion of the partonic system created in the collision. The case of ALICE detector is explicitly considered.

Case, Inflection, and Subject Licensing in Child Catalan and Spanish.

ERIC Educational Resources Information Center

Grindstead, John

2000-01-01

Development of specified tense and number morphology in child Catalan and Spanish was found to correlate with the onset of overt subject use in one monolingual child Spanish speaker and four monolingual child Catalan speakers who were studied longitudinally. (Author/VWL)

The role of socioeconomic status in longitudinal trends of cholera in Matlab, Bangladesh, 1993-2007.

PubMed

Root, Elisabeth Dowling; Rodd, Joshua; Yunus, Mohammad; Emch, Michael

2013-01-01

There has been little evidence of a decline in the global burden of cholera in recent years as the number of cholera cases reported to WHO continues to rise. Cholera remains a global threat to public health and a key indicator of lack of socioeconomic development. Overall socioeconomic development is the ultimate solution for control of cholera as evidenced in developed countries. However, most research has focused on cross-county comparisons so that the role of individual- or small area-level socioeconomic status (SES) in cholera dynamics has not been carefully studied. Reported cases of cholera in Matlab, Bangladesh have fluctuated greatly over time and epidemic outbreaks of cholera continue, most recently with the introduction of a new serotype into the region. The wealth of longitudinal data on the population of Matlab provides a unique opportunity to explore the impact of socioeconomic status and other demographic characteristics on the long-term temporal dynamics of cholera in the region. In this population-based study we examine which factors impact the initial number of cholera cases in a bari at the beginning of the 0139 epidemic and the factors impacting the number of cases over time. Cholera data were derived from the ICDDR,B health records and linked to socioeconomic and geographic data collected as part of the Matlab Health and Demographic Surveillance System. Longitudinal zero-inflated Poisson (ZIP) multilevel regression models are used to examine the impact of environmental and socio-demographic factors on cholera counts across baris. Results indicate that baris with a high socioeconomic status had lower initial rates of cholera at the beginning of the 0139 epidemic (γ(01) = -0.147, p = 0.041) and a higher probability of reporting no cholera cases (α(01) = 0.156, p = 0.061). Populations in baris characterized by low SES are more likely to experience higher cholera morbidity at the beginning of an epidemic than populations in high SES baris.

Expectations versus Reality: The Case of Liberal Studies in Hong Kong's New Senior Secondary Reforms

ERIC Educational Resources Information Center

Fung, Dennis

2016-01-01

This article reports the findings of a five-year longitudinal study investigating the introduction of Liberal Studies in the context of Hong Kong's new senior secondary educational reforms. The aim of this empirical research, which adopted diachronic analysis to allow comparisons over time, was to compare teachers' and students' perceptions of the…

Dynamic Analysis of UTAUT: The Case of Microsoft Project Management Software

ERIC Educational Resources Information Center

Abualbasal, Wejdan; Abu-Shanab, Emad; Al-Quraan, Heba

2016-01-01

The technology adoption domain is rich with studies that utilized a cross-sectional snapshot of subjects' perceptions regarding the adoption of new technology. This research tried to implement a longitudinal study that took three measures within 4 months to estimate the influence of time and experience on students' perceptions. The study adopted a…

Finding Their Way on: Career Decision-Making Processes of Urban Science Teachers

ERIC Educational Resources Information Center

Rinke, Carol R.

2009-01-01

This article reports on a research study investigating the career decision-making processes of urban science teachers as one element central to understanding the high rates of attrition in the field. Using a longitudinal, prospective, context- and subject-specific approach, this study followed the career decisions of case study teachers over a…

Preparing for the Educational Black Hole? Teachers' Learning in Two Pathways into Middle School Social Studies Teaching

ERIC Educational Resources Information Center

Conklin, Hilary G.

2010-01-01

The author presents findings from the first phase of a longitudinal, comparative case study that investigates what teachers learn about intellectually demanding social studies teaching at the middle school level from two distinctive teacher education pathways: a specialized middle school teacher education program and a secondary social studies…

Psychological stress and burnout in medical students: a five-year prospective longitudinal study.

PubMed

Guthrie, E; Black, D; Bagalkote, H; Shaw, C; Campbell, M; Creed, F

1998-05-01

The aim of this study was to assess psychological morbidity and symptoms of burnout in medical students during their undergraduate training, and to identify baseline factors that predict psychological morbidity in students in the final year of the course. It was a 5-year prospective longitudinal cohort study. Students were assessed in years 1, 4 and 5 of their medical undergraduate training by means of the GHQ-12 and the Maslach Burnout Inventory. 172 (84.3%), 157 (77.0%) and 155 (75.9%) students out of an original group of 204 completed assessments in years 1, 4 and 5, respectively. 18 students were above threshold on the GHQ-12 on all three occasions, 25 on two occasions and 43 on one occasion; 69 students were never a 'case'. Students who were cases on two or more occasions were more likely to find the medical course stressful during the first year, but not subsequent years. There was no significant difference between the percentages of men and women who scored as cases on the GHQ-12 in any of the years. The best predictor of psychological morbidity in the final year of the course was the GHQ-12 score in year 1. This study suggests that a small group of students repeatedly experience psychological distress during their medical training.

Intraoperative performance and postoperative outcome comparison of longitudinal, torsional, and transversal phacoemulsification machines.

PubMed

Christakis, Panos G; Braga-Mele, Rosa M

2012-02-01

To compare the intraoperative performance and postoperative outcomes of 3 phacoemulsification machines that use different modes. Kensington Eye Institute, Toronto, Ontario, Canada. Comparative case series. This chart and video review comprised consecutive eligible patients who had phacoemulsification by the same surgeon using a Whitestar Signature Ellips-FX (transversal), Infiniti-Ozil-IP (torsional), or Stellaris (longitudinal) machine. The review included 98 patients. Baseline characteristics in the groups were similar; the mean nuclear sclerosis grade was 2.0 ± 0.8. There were no significant intraoperative complications. The torsional machine averaged less phacoemulsification needle time (83 ± 33 seconds) than the transversal (99 ± 40 seconds; P=.21) or longitudinal (110 ± 45 seconds; P=.02) machines; the difference was accentuated in cases with high-grade nuclear sclerosis. The torsional machine had less chatter and better followability than the transversal or longitudinal machines (P<.001). The torsional and longitudinal machines had better anterior chamber stability than the transversal machine (P<.001). Postoperatively, the torsional machine yielded less central corneal edema than the transversal (P<.001) and longitudinal (P=.04) machines, corresponding to a smaller increase in mean corneal thickness (torsional 5%, transversal 10%, longitudinal 12%; P=.04). Also, the torsional machine had better 1-day postoperative visual acuities (P<.001). All 3 phacoemulsification machines were effective with no significant intraoperative complications. The torsional machine outperformed the transversal and longitudinal machines, with a lower mean needle time, less chatter, and improved followability. This corresponded to less corneal edema 1 day postoperatively and better visual acuity. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Keeping Connected: A Review of the Research Relationship

ERIC Educational Resources Information Center

Moss, Julianne; Hay, Trevor

2014-01-01

In this paper, some key findings of the Keeping Connected project are discussed in light of the methodological challenges of developing an analytical approach in a large-scale study, particularly in starting with open-ended, participant-selected, digital still visual images as part of 31 longitudinal case studies. The paper works to clarify the…

A 20-Year Examination of the Perceptions of Business School Interns: A Longitudinal Case Study

ERIC Educational Resources Information Center

Cook, Sherry James; Stokes, Amy; Parker, Richard Stephen

2015-01-01

The authors examined students' attitudes toward specific elements of an ongoing internship program. The study sample consisted of 816 student interns from 25 different colleges and universities. Results indicate that despite significant changes in instructional design and the incorporation of new technologies into the learning environment,…

"Just Having a Job": Career Advancement for Low-Wage Workers with Intellectual and Developmental Disabilities

ERIC Educational Resources Information Center

Lindstrom, Lauren; Hirano, Kara A.; McCarthy, Colleen; Alverson, Charlotte Y.

2014-01-01

This study examined career development and early employment experiences for four young adults with intellectual and developmental disabilities. Researchers used a multiple-method, multiple case-study longitudinal design to explore career development within the context of family systems, high school and transition programs, adult services, and…

Parent-Infant Vocalisations at 12 Months Predict Psychopathology at 7 Years

ERIC Educational Resources Information Center

Allely, C. S.; Purves, D.; McConnachie, A.; Marwick, H.; Johnson, P.; Doolin, O.; Puckering, C.; Golding, J.; Gillberg, C.; Wilson, P.

2013-01-01

This study investigated the utility of adult and infant vocalisation in the prediction of child psychopathology. Families were sampled from the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. Vocalisation patterns were obtained from 180 videos (60 cases and 120 randomly selected sex-matched controls) of parent-infant…

Raising Reading Achievement in an "At Risk", Low Socioeconomic, Multicultural Intermediate School

ERIC Educational Resources Information Center

Fletcher, Jo; Grimley, Michael; Greenwood, Janinka; Parkhill, Faye

2013-01-01

This article focuses on a multicultural, low socioeconomic, intermediate school that over the 4 years of this longitudinal, qualitative, case study made substantial positive shifts in developing a more effective learning environment and improving students' reading achievement. The study found that the factors appearing to have the most influence…

Toward an Instructional Approach to Developing Interactive Second Language Listening

ERIC Educational Resources Information Center

Yeldham, Michael; Gruba, Paul

2014-01-01

This study details the development of six second language learners in an English listening course that focused on developing their bottom-up listening skills. The research employed longitudinal multi-case studies to chart the development of these lower proficiency-level Taiwanese university learners, and their progress in the course was analysed…

Student Learning and Engagement in the Context of Curriculum Integration

ERIC Educational Resources Information Center

Brinegar, Kathleen; Bishop, Penny A.

2011-01-01

Although curriculum integration has a long history of myriad models, rarely have those stakeholders most connected to the practice--the students--been consulted about the efficacy of the approach. This study applied a longitudinal, intrinsic case study approach (Stake, 2000) to examine middle school students' perceptions of learning and engagement…

Reasoning about Race and Pedagogy in Two Preservice Science Teachers: A Critical Race Theory Analysis

ERIC Educational Resources Information Center

Larkin, Douglas B.; Maloney, Tanya; Perry-Ryder, Gail M.

2016-01-01

This study describes the experiences of two preservice science teachers as they progress through their respective teacher education programs and uses critical race theory to examine the manner in which conceptions about race and its pedagogical implications change over time. Using a longitudinal case study method, participants' conceptual…

Factors Influencing Enrolment: A Case Study from Birth to Twenty, the 1990 Birth Cohort in Soweto-Johannesburg

ERIC Educational Resources Information Center

Richter, Linda M.; Panday, Saadhna; Norris, Shane A.

2009-01-01

Longitudinal studies offer significant advantages in rendering data commensurate with the complexity of human development. However, incomplete enrolment and attrition over time can introduce bias. Furthermore, there is a scarcity of evaluative information on cohorts in developing countries. This paper documents various strategies adopted to…

The Role of Facilitators in Project Action Learning Implementation

ERIC Educational Resources Information Center

Cao, Rui; Chuah, Kong Bieng; Chao, Yiu Chung; Kwong, Kar Fai; Law, Mo Yin

2012-01-01

Purpose: This paper addresses the importance of a more proactive role of organizational learning (OL) facilitators, learning motivation reinforcer, through a two-part longitudinal study in a case company. The first part of this study aims to investigate and analyze some unexpected challenges in the project action learning-driven (PAL) OL…

Cultivating Imaginative Thinking: Teacher Strategies Used in High-Performing Arts Education Classrooms

ERIC Educational Resources Information Center

Fleming, Josephine; Gibson, Robyn; Anderson, Michael; Martin, Andrew J.; Sudmalis, David

2016-01-01

This article reports on recent case-study research that examined teacher- and student-level processes in nine Australian arts classrooms. The selected classrooms, based on the results of a connected longitudinal study, demonstrated strong positive links between arts participation and academic motivation, engagement and achievement. The focus here…

Half Century of Marriage: Continuity or Change?

ERIC Educational Resources Information Center

Weishaus, Sylvia; Field, Dorothy

Current research focusing on long-term marriages have assessed marriages at one time period only. To sort out age and stage differences from cohort effects, a longitudinal case study analysis was undertaken with the 17 surviving couples of the Berkeley Older Generation Study, a group that has been interviewed in young adulthood (1929-30), in…

Case Studies in Literacy Development.

ERIC Educational Resources Information Center

Purvis, Don

The report details results of a research project to monitor and map the literacy development of three learners of English as a Second Language (ESL) studying in an Australian English program for adult migrants. The objective was to gain a longitudinal picture of their reading and writing development over a period of nine months. Five additional…

The "Synergies" Research-Practice Partnership Project: A "2020 Vision" Case Study

ERIC Educational Resources Information Center

Falk, John H.; Dierking, Lynn D.; Staus, Nancy L.; Wyld, Jennifer N.; Bailey, Deborah L.; Penuel, William R.

2016-01-01

This paper, describes "Synergies," an on-going longitudinal study and design effort, being conducted in a diverse, under-resourced community in Portland, Oregon, with the goal of measurably improving STEM learning, interest and participation by early adolescents, both in school and out of school. Authors examine how the work of this…

A Journey from STEM to STEAM: A Middle School Case Study

ERIC Educational Resources Information Center

Hunter-Doniger, Tracey; Sydow, Lindsey

2016-01-01

This article examines the initial journey of a middle school in South Carolina from a STEM (science, technology, engineering, and math) curriculum to a STEAM (STEM + art) curriculum. This is the first of a three-year longitudinal study that investigated the perceptions of the effectiveness, relative importance, and sustainability of a STEAM…

Modeling zero-modified count and semicontinuous data in health services research part 2: case studies.

PubMed

Neelon, Brian; O'Malley, A James; Smith, Valerie A

2016-11-30

This article is the second installment of a two-part tutorial on the analysis of zero-modified count and semicontinuous data. Part 1, which appears as a companion piece in this issue of Statistics in Medicine, provides a general background and overview of the topic, with particular emphasis on applications to health services research. Here, we present three case studies highlighting various approaches for the analysis of zero-modified data. The first case study describes methods for analyzing zero-inflated longitudinal count data. Case study 2 considers the use of hurdle models for the analysis of spatiotemporal count data. The third case study discusses an application of marginalized two-part models to the analysis of semicontinuous health expenditure data. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Acquired Bilateral Longitudinal True Leukonychia in a 35-year-old Woman

PubMed Central

Mokhtari, Fatemeh; Mozafarpoor, Samaneh; Nouraei, Saeid; Nilforoushzadeh, Mohammad Ali

2016-01-01

Acquired bilateral longitudinal true leukonychia is a rare disorder. We present a case of a 35-year-old healthy woman presented with this unusual and rare manifestation. She mentioned a history of unprotected exposure to detergents and bleaching chemical agents. Considering her low zinc level, she was prescribed with zinc capsules and recommended to avoid chemical substances for 6 months. During bimonthly follow-up, her zinc level turned normal, and leukonychia subsequently disappeared. Bilateral longitudinal true leukonychia in the nails due to zinc deficiency and exposure to chemical substances has not been reported previously. Direct and indirect effects of chemical substances on matrix and the effect of zinc deficiency on healing process should be considered in these cases. PMID:27857831

Assessment of score- and Rasch-based methods for group comparison of longitudinal patient-reported outcomes with intermittent missing data (informative and non-informative).

PubMed

de Bock, Élodie; Hardouin, Jean-Benoit; Blanchin, Myriam; Le Neel, Tanguy; Kubis, Gildas; Sébille, Véronique

2015-01-01

The purpose of this study was to identify the most adequate strategy for group comparison of longitudinal patient-reported outcomes in the presence of possibly informative intermittent missing data. Models coming from classical test theory (CTT) and item response theory (IRT) were compared. Two groups of patients' responses to dichotomous items with three times of assessment were simulated. Different cases were considered: presence or absence of a group effect and/or a time effect, a total of 100 or 200 patients, 4 or 7 items and two different values for the correlation coefficient of the latent trait between two consecutive times (0.4 or 0.9). Cases including informative and non-informative intermittent missing data were compared at different rates (15, 30 %). These simulated data were analyzed with CTT using score and mixed model (SM) and with IRT using longitudinal Rasch mixed model (LRM). The type I error, the power and the bias of the group effect estimations were compared between the two methods. This study showed that LRM performs better than SM. When the rate of missing data rose to 30 %, estimations were biased with SM mainly for informative missing data. Otherwise, LRM and SM methods were comparable concerning biases. However, regardless of the rate of intermittent missing data, power of LRM was higher compared to power of SM. In conclusion, LRM should be favored when the rate of missing data is higher than 15 %. For other cases, SM and LRM provide similar results.

Longitudinal plasma metabolic profiles, infant feeding, and islet autoimmunity in the MIDIA study.

PubMed

Jørgenrud, Benedicte; Stene, Lars C; Tapia, German; Bøås, Håkon; Pepaj, Milaim; Berg, Jens P; Thorsby, Per M; Orešič, Matej; Hyötyläinen, Tuulia; Rønningen, Kjersti S

2017-03-01

The aim of this study was to investigate the longitudinal plasma metabolic profiles in healthy infants and the potential association with breastfeeding duration and islet autoantibodies predictive of type 1 diabetes. Up to four longitudinal plasma samples from age 3 months from case children who developed islet autoimmunity (n = 29) and autoantibody-negative control children (n = 29) with the HLA DR4-DQ8/DR3-DQ2 genotype were analyzed using two-dimensional gas chromatography coupled to a time-of-flight mass spectrometer for detection of small polar metabolites. Plasma metabolite levels were found to depend strongly on age, with fold changes varying up to 50% from age 3 to 24 months (p < 0.001 after correction for multiple testing). Tyrosine levels tended to be lower in case children, but this was not significant after correction for multiple testing. Ornithine levels were lower in case children compared with the controls at the time of seroconversion, but the difference was not statistically significant after correcting for multiple testing. Breastfeeding for at least 3 months as compared with shorter duration was associated with higher plasma levels of isoleucine, and lower levels of methionine and 3,4-dihydroxybutyric acid at 3 months of age. Plasma levels of several small, polar metabolites changed with age during early childhood, independent of later islet autoimmunity status and sex. Breastfeeding was associated with higher levels of branched-chain amino acids, and lower levels of methionine and 3,4-dihydroxybutyric acid. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Knowledge Growth, Academic Beliefs and Motivation of Students in Business and Economics--A Longitudinal German Case Study

ERIC Educational Resources Information Center

Biewen, Martin; Happ, Roland; Schmidt, Susanne; Zlatkin-Troitschanskaia, Olga

2018-01-01

In this study we examine the determinants of and the relationship among economic knowledge, epistemological beliefs, and extrinsic and intrinsic motivation over the course of undergraduate studies in a sample of students of business and economics at a university in Germany. We found economic knowledge increased over the course of studies,…

FE Analysis of Buckling Behavior Caused by Welding in Thin Plates of High Tensile Strength Steel

NASA Astrophysics Data System (ADS)

Wang, Jiangchao; Rashed, Sherif; Murakawa, Hidekazu

2014-12-01

The target of this study was to investigate buckling behavior during the entire welding process which consists of the heating and the cooling processes. For thin plate structures made of high tensile strength steel, not only residual buckling during or after cooling down but also transient buckling during heating may occur. The thermal elastic plastic FE analysis to investigate welding-induced buckling during the entire welding process is presented. Because of the high yield stress of high tensile strength steel, larger longitudinal compressive thermal stress is produced near the welding line compared with that in the case of carbon steel. Therefore, the plate may buckle due to thermal expansion, before the material nears yielding. During cooling down, the longitudinal compressive thermal stress close to the welding line disappears, and longitudinal tensile residual stress is produced due to contraction. Meanwhile, longitudinal compressive residual stress occurs far from the welding line to balance the tensile stress close to the welding line. This distribution of longitudinal residual stress would change the deformed dish shape of transient buckling into a saddle buckling type when the stress exceeds the critical buckling condition.

Longitudinal waves in carbon nanotubes in the presence of transverse magnetic field and elastic medium

NASA Astrophysics Data System (ADS)

Liu, Hu; Liu, Hua; Yang, Jialing

2017-09-01

In the present paper, the coupling effect of transverse magnetic field and elastic medium on the longitudinal wave propagation along a carbon nanotube (CNT) is studied. Based on the nonlocal elasticity theory and Hamilton's principle, a unified nonlocal rod theory which takes into account the effects of small size scale, lateral inertia and radial deformation is proposed. The existing rod theories including the classic rod theory, the Rayleigh-Love theory and Rayleigh-Bishop theory for macro solids can be treated as the special cases of the present model. A two-parameter foundation model (Pasternak-type model) is used to represent the elastic medium. The influence of transverse magnetic field, Pasternak-type elastic medium and small size scale on the longitudinal wave propagation behavior of the CNT is investigated in detail. It is shown that the influences of lateral inertia and radial deformation cannot be neglected in analyzing the longitudinal wave propagation characteristics of the CNT. The results also show that the elastic medium and the transverse magnetic field will also affect the longitudinal wave dispersion behavior of the CNT significantly. The results obtained in this paper are helpful for understanding the mechanical behaviors of nanostructures embedded in an elastic medium.

Structural Damage Detection Using Slopes of Longitudinal Vibration Shapes

DOE PAGES

Xu, W.; Zhu, W. D.; Smith, S. A.; ...

2016-03-18

While structural damage detection based on flexural vibration shapes, such as mode shapes and steady-state response shapes under harmonic excitation, has been well developed, little attention is paid to that based on longitudinal vibration shapes that also contain damage information. This study originally formulates a slope vibration shape for damage detection in bars using longitudinal vibration shapes. To enhance noise robustness of the method, a slope vibration shape is transformed to a multiscale slope vibration shape in a multiscale domain using wavelet transform, which has explicit physical implication, high damage sensitivity, and noise robustness. These advantages are demonstrated in numericalmore » cases of damaged bars, and results show that multiscale slope vibration shapes can be used for identifying and locating damage in a noisy environment. A three-dimensional (3D) scanning laser vibrometer is used to measure the longitudinal steady-state response shape of an aluminum bar with damage due to reduced cross-sectional dimensions under harmonic excitation, and results show that the method can successfully identify and locate the damage. Slopes of longitudinal vibration shapes are shown to be suitable for damage detection in bars and have potential for applications in noisy environments.« less

Assessing corporate project impacts in changeable contexts: A human rights perspective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salcito, Kendyl, E-mail: kendyl.salcito@unibas.ch; University of Basel, P.O. Box, CH-4003 Basel; NomoGaia, 1900 Wazee Street, Suite 303, Denver, CO 80202

Project-level impact assessment was originally conceived as a snapshot taken in advance of project implementation, contrasting current conditions with a likely future scenario involving a variety of predicted impacts. Current best practice guidance has encouraged a shift towards longitudinal assessments from the pre-project stage through the implementation and operating phases. Experience and study show, however, that assessment of infrastructure-intensive projects rarely endures past the project's construction phase. Negative consequences for environmental, social and health outcomes have been documented. Such consequences clarify the pressing need for longitudinal assessment in each of these domains, with human rights impact assessment (HRIA) as anmore » umbrella over, and critical augmentation of, environmental, social and health assessments. Project impacts on human rights are more closely linked to political, economic and other factors beyond immediate effects of a company's policy and action throughout the project lifecycle. Delineating these processes requires an adequate framework, with strategies for collecting longitudinal data, protocols that provide core information for impact assessment and guidance for adaptive mitigation strategies as project-related effects change over time. This article presents general principles for the design and implementation of sustained, longitudinal HRIA, based on experience assessing and responding to human rights impact in a uranium mining project in Malawi. The case study demonstrates the value of longitudinal assessment both for limiting corporate risk and improving human welfare. - Graphical abstract: Assessing changes in human rights condition as affected by both project and context, over time. - Highlights: • Corporate capital projects affect human rights in myriad ways. • Ongoing, longitudinal impact assessment techniques are needed. • We present an approach for conducting longitudinal human rights impact assessment. • Our methodology allows distinguishing corporate impacts from contextual changes. • Promptly observing context changes and impacts enables companies to react nimbly.« less

Interpreting Early Career Trajectories

ERIC Educational Resources Information Center

Barnatt, Joan; Gahlsdorf Terrell, Dianna; D'Souza, Lisa Andries; Jong, Cindy; Cochran-Smith, Marilyn; Viesca, Kara Mitchell; Gleeson, Ann Marie; McQuillan, Patrick; Shakman, Karen

2017-01-01

Career decisions of four teachers are explored through the concept of figured worlds in this qualitative, longitudinal case study. Participants were purposefully chosen for similarity at entry, with a range of career trajectories over time. Teacher career paths included remaining in one school, repeated changes in schools, attrition after…

Development of an E-Learning Culture in the Australian Army

ERIC Educational Resources Information Center

Newton, Diane; Ellis, Allan

2007-01-01

For organisations with hierarchical management and training cultures, e-learning provides opportunities for standardising content, delivery, and course management while challenging traditional teacher-student relationships. This research based case study of the Australian Army provided a longitudinal perspective of the diverse factors influencing…

A comparison of multiple imputation methods for incomplete longitudinal binary data.

PubMed

Yamaguchi, Yusuke; Misumi, Toshihiro; Maruo, Kazushi

2018-01-01

Longitudinal binary data are commonly encountered in clinical trials. Multiple imputation is an approach for getting a valid estimation of treatment effects under an assumption of missing at random mechanism. Although there are a variety of multiple imputation methods for the longitudinal binary data, a limited number of researches have reported on relative performances of the methods. Moreover, when focusing on the treatment effect throughout a period that has often been used in clinical evaluations of specific disease areas, no definite investigations comparing the methods have been available. We conducted an extensive simulation study to examine comparative performances of six multiple imputation methods available in the SAS MI procedure for longitudinal binary data, where two endpoints of responder rates at a specified time point and throughout a period were assessed. The simulation study suggested that results from naive approaches of a single imputation with non-responders and a complete case analysis could be very sensitive against missing data. The multiple imputation methods using a monotone method and a full conditional specification with a logistic regression imputation model were recommended for obtaining unbiased and robust estimations of the treatment effect. The methods were illustrated with data from a mental health research.

Nonlinear panel flutter in a rarefied atmosphere - Aerodynamic shear stress effects

NASA Technical Reports Server (NTRS)

Resende, Hugo B.

1991-01-01

The panel flutter phenomenon is studied assuming free-molecule flow. This kind of analysis is relevant in the case of hypersonic flight vehicles traveling at high altitudes, especially in the leeward portion of the vehicle. In these conditions the aerodynamic shear can be expected to be considerably larger than the pressure at a given point, so that the effects of such a loading are incorporated into the structural model. This is accomplished by introducing distributed longitudinal and bending moment loads. The former can lead to buckling of the panel, with the second mode in the case of a simply-supported panel playing a important role, and becoming the dominant mode in the solution. The presence of equivalent springs in the longitudinal direction at the panel's ends also becomes of relative importance, even for the evaluation of the linear flutter parameter. Finally, the behavior of the system is studied in the presence of applied compressive forces, that is, classical buckling.

An unusual stress fracture: Bilateral posterior longitudinal stress fracture of tibia.

PubMed

Malkoc, Melih; Korkmaz, Ozgur; Ormeci, Tugrul; Oltulu, Ismail; Isyar, Mehmet; Mahirogulları, Mahir

2014-01-01

Stress fractures (SF) occur when healthy bone is subjected to cyclic loading, which the normal carrying range capacity is exceeded. Usually, stress fractures occur at the metatarsal bones, calcaneus, proximal or distal tibia and tends to be unilateral. This article presents a 58-year-old male patient with bilateral posterior longitudinal tibial stress fractures. A 58 years old male suffering for persistent left calf pain and decreased walking distance for last one month and after imaging studies posterior longitudinal tibial stress fracture was detected on his left tibia. After six months the patient was admitted to our clinic with the same type of complaints in his right leg. All imaging modalities and blood counts were performed and as a result longitudinal posterior tibial stress fractures were detected on his right tibia. Treatment of tibial stress fracture includes rest and modified activity, followed by a graded return to activity commensurate with bony healing. We have applied the same treatment protocol and our results were acceptable but our follow up time short for this reason our study is restricted for separate stress fractures of the posterior tibia. Although the main localization of tibial stress fractures were unilateral, anterior and transverse pattern, rarely, like in our case, the unusual bilateral posterior localization and longitudinal pattern can be seen. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

The long term impact of cataract surgery on quality of life, activities and poverty: results from a six year longitudinal study in Bangladesh and the Philippines.

PubMed

Danquah, Lisa; Kuper, Hannah; Eusebio, Cristina; Rashid, Mamunur Akm; Bowen, Liza; Foster, Allen; Polack, Sarah

2014-01-01

Cataract surgery has been shown to improve quality of life and household economy in the short term. However, it is unclear whether these benefits are sustained over time. This study aims to assess the six year impact of cataract surgery on health related quality of life (HRQoL), daily activities and economic poverty in Bangladesh and The Philippines. This was a longitudinal study. At baseline people aged ≥50 years with visual impairment due to cataract ('cases') and age-, sex-matched controls without visual impairment were interviewed about vision specific and generic HRQoL, daily activities and economic indicators (household per capita expenditure, assets and self-rated wealth). Cases were offered free or subsidised cataract surgery. Cases and controls were re-interviewed approximately one and six years later. At baseline across the two countries there were 455 cases and 443 controls. Fifty percent of cases attended for surgery. Response rates at six years were 47% for operated cases and 53% for controls. At baseline cases had poorer health and vision related QoL, were less likely to undertake productive activities, more likely to receive assistance with activities and were poorer compared to controls (p<0.05). One year after surgery there were significant increases in HRQoL, participation and time spent in productive activities and per capita expenditure and reduction in assistance with activities so that the operated cases were similar to controls. These increases were still evident after six years with the exception that time spent on productive activities decreased among both cases and controls. Cataract causing visual loss is associated with reduced HRQoL and economic poverty among older adults in low-income countries. Cataract surgery improves the HRQoL of the individual and economy of the household. The findings of this study suggest these benefits are sustained in the long term.

Absence of asymptomatic cases of malaria in a historically endemic indigenous locality of the Department of Caaguazú, Paraguay: moving toward elimination.

PubMed

Barrios, Eugenia Duarte de; Russomando, Graciela; Puerto, Florencia Del

2016-01-01

Paraguay was among the 16 countries that reported zero indigenous malaria cases in 2014. A cross-sectional observational descriptive study was performed in 100 adults from Santa Teresa, Paraguay. Parasite detection was carried out using seminested multiplex polymerase chain reaction (PCR) and microscopy. Among the participants, 44% were female and 56% were male, and 89% had a malaria history. No parasites were detected with either of the methods. There were no asymptomatic cases in Santa Teresa, and this finding is very promising. A longitudinal study should be performed to confirm that there are no asymptomatic cases in this locality.

The Cascade of Medical Services and Associated Longitudinal Costs Due to Nonadherent Magnetic Resonance Imaging for Low Back Pain

PubMed Central

Webster, Barbara S.; Choi, YoonSun; Bauer, Ann Z.; Cifuentes, Manuel

2014-01-01

Study Design. Retrospective cohort study. Objective. To compare type, timing, and longitudinal medical costs incurred after adherent versus nonadherent magnetic resonance imaging (MRI) for work-related low back pain. Summary of Background Data. Guidelines advise against MRI for acute uncomplicated low back pain, but is an option for persistent radicular pain after a trial of conservative care. Yet, MRI has become frequent and often nonadherent. Few studies have documented the nature and impact of medical services (including type and timing) initiated by nonadherent MRI. Methods. A longitudinal, workers' compensation administrative data source was accessed to select low back pain claims filed between January 1, 2006 and December 31, 2006. Cases were grouped by MRI timing (early, timely, no MRI) and subgrouped by severity (“less severe,” “more severe”) (final cohort = 3022). Health care utilization for each subgroup was evaluated at 3, 6, 9, and 12 months post-MRI. Multivariate logistic regression models examined risk of receiving subsequent diagnostic studies and/or treatments, adjusting for pain indicators and demographic covariates. Results. The adjusted relative risks for MRI group cases to receive electromyography, nerve conduction testing, advanced imaging, injections, and surgery within 6 months post-MRI risks in the range from 6.5 (95% CI: 2.20–19.09) to 54.9 (95% CI: 22.12–136.21) times the rate for the referent group (no MRI less severe). The timely and early MRI less severe subgroups had similar adjusted relative risks to receive most services. The early MRI more severe subgroup cases had generally higher adjusted relative risks than timely MRI more severe subgroup cases. Medical costs for both early MRI subgroups were highest and increased the most over time. Conclusion. The impact of nonadherent MRI includes a wide variety of expensive and potentially unnecessary services, and occurs relatively soon post-MRI. Study results provide evidence to promote provider and patient conversations to help patients choose care that is based on evidence, free from harm, less costly, and truly necessary. Level of Evidence: N/A PMID:24831502

Doubly robust estimation of generalized partial linear models for longitudinal data with dropouts.

PubMed

Lin, Huiming; Fu, Bo; Qin, Guoyou; Zhu, Zhongyi

2017-12-01

We develop a doubly robust estimation of generalized partial linear models for longitudinal data with dropouts. Our method extends the highly efficient aggregate unbiased estimating function approach proposed in Qu et al. (2010) to a doubly robust one in the sense that under missing at random (MAR), our estimator is consistent when either the linear conditional mean condition is satisfied or a model for the dropout process is correctly specified. We begin with a generalized linear model for the marginal mean, and then move forward to a generalized partial linear model, allowing for nonparametric covariate effect by using the regression spline smoothing approximation. We establish the asymptotic theory for the proposed method and use simulation studies to compare its finite sample performance with that of Qu's method, the complete-case generalized estimating equation (GEE) and the inverse-probability weighted GEE. The proposed method is finally illustrated using data from a longitudinal cohort study. © 2017, The International Biometric Society.

Skin, a mirror reflecting diabetes mellitus: A longitudinal study in a tertiary care hospital in Gujarat.

PubMed

Vahora, Roshni; Thakkar, Sejal; Marfatia, Yogesh

2013-07-01

Diabetes mellitus (DM) is the most common of the endocrine disorders. Mucocutaneous manifestations of diabetes mellitus are many and vary from trivial to life-threatening. Sometimes, mucocutaneous disorders may herald the onset of diabetes. To study the pattern of mucocutaneous manifestations in diabetics and role of it in diagnosing diabetes mellitus and its complications. It was a longitudinal observational study of patients having diabetes with skin complaints attending skin outdoor department or admitted in wards for any reason in a tertiary care hospital. Total 300 patients were included in the study. Detailed history, clinical examination, and relevant investigations were done to diagnose the mucocutaneous disorders, diabetes, and diabetic complications. The data was analyzed by using Epi info software. Demographic profile shown majority of cases (78.66%) in more than 40 years of age with almost equal male and female preponderance. Mucocutaneous manifestations as presenting feature of diabetes were observed in 21.67% cases. Infections were most common in 119 (39.66%) cases, followed by acanthosis nigricans in 46 (15.33%) cases. Various associated complications like hypertension, retinopathy, hyperlipidemia, coronary artery disease, neuropathy, nephropathy, and diabetic ketoacidosis were observed in 160 (53.3%). Skin is the mirror, which reflects internal diseases; this aptly applies to skin and diabetes mellitus. Through awareness about cutaneous manifestations of DM, dermatologist can not only take credit for detecting DM but also facilitate early diagnosis of systemic complications of DM. This is immensely beneficial to patients in long run.

The Effect of Study Abroad on Intercultural Competence: A Longitudinal Case Study of International Postgraduate Students at a British University

ERIC Educational Resources Information Center

Schartner, Alina

2016-01-01

Educational sojourns abroad are not only increasingly popular; it is also believed that they have many positive outcomes for students. The transformative potential of a study sojourn abroad has been claimed in linguistic and broader intercultural terms (e.g. Brown [2009] "The Transformative Power of the International Sojourn: An Ethnographic…

Implementing a Statewide Mandated Career Pathways/Programs of Study School Reform Model: Select Findings from a Multisite Case Study

ERIC Educational Resources Information Center

Withington, Cairen; Hammond, Cathy; Mobley, Catherine; Stipanovic, Natalie; Sharp, Julia L.; Stringfield, Sam; Drew, Sam F., Jr.

2012-01-01

"A Longitudinal Study of the South Carolina Personal Pathways to Success Initiative" (see Hammond, Drew, et al., 2011) follows the implementation of a statewide mandated career-focused school reform policy in one U.S. state. The research focuses on eight diverse high schools in the state, personnel at those schools, and approximately…

L2 Academic Discourse Socialization through Oral Presentations: An Undergraduate Student's Learning Trajectory in Study Abroad

ERIC Educational Resources Information Center

Kobayashi, Masaki

2016-01-01

The present study provides an in-depth, longitudinal account of an undergraduate student's L2 discourse socialization in an academic exchange program in Canada. By invoking Rogoff's (1995) notion of participatory appropriation, this qualitative case study examined an L2 student's task-related strategies and performance as they evolved over time in…

The Multi-Literacy Development of a Young Trilingual Child: Four Leading Literacy Activities from Birth to Age Six

ERIC Educational Resources Information Center

Kim, Mi Song

2014-01-01

This study examines the multiplicity of literacies while incorporating multiple modes of meaning to understand a young trilingual child's meaning-making processes. This qualitative study reports the results of a combination of ethnographic observations and a longitudinal case study of one child's multi-literacy development from birth to…

A Winding Road--Professional Trajectories from Higher Education to Working Life: A Case Study of Political Science and Psychology Graduates

ERIC Educational Resources Information Center

Nystrom, Sofia; Dahlgren, Madeleine Abrandt; Dahlgren, Lars Owe

2008-01-01

This qualitative and longitudinal study focuses on graduate employment and the development of graduate employment paths. The aim of this article is to explore the present professional trajectory from higher education to working life, with particular reference to graduates from two different study programmes at Linkoping University in Sweden:…

Early Family Environments May Moderate Prediction of Low Educational Attainment in Adulthood: The Cases of Childhood Hyperactivity and Authoritarian Parenting

ERIC Educational Resources Information Center

Flouri, Eirini

2007-01-01

Using longitudinal data from the 1970 British Cohort Study, this study explored conditions under which the effects of risk factors for low educational attainment might be moderated. Two different risk factors, hyperactivity and maternal authoritarian parenting attitudes, were studied. The results showed that on the whole these two risk factors…

Offshore Outsourcing Teacher Inservice Education: The Long-Term Effects of a Four-Month Pedagogical Program on Japanese Teachers of English

ERIC Educational Resources Information Center

Cook, Melodie

2010-01-01

This longitudinal study tracked five public junior and senior high school Japanese teachers of English (JTEs) who were sponsored by the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) to study English and Communicative Language Teaching (CLT) pedagogy at a host university in Canada. This qualitative case study found…

Student Leadership Development: A Functional Framework

ERIC Educational Resources Information Center

Hine, Gregory Stephen Colin

2014-01-01

This article presents a longitudinal, qualitative case study of a student leadership program in a Catholic secondary school in Perth, Western Australia. Data were collected over a period of three years through multiple methods, including one-on-one interviewing, focus group interviewing, document searches, field notes, and researcher reflective…

Infinite coherence time of edge spins in finite-length chains

NASA Astrophysics Data System (ADS)

Maceira, Ivo A.; Mila, Frédéric

2018-02-01

Motivated by the recent observation that exponentially long coherence times can be achieved for edge spins in models with strong zero modes, we study the impact of level crossings in finite-length spin chains on the dynamics of the edge spins. Focusing on the X Y spin-1 /2 chain with a transverse or longitudinal magnetic field, two models relevant to understanding recent experimental results on cobalt adatoms, we show that the edge spins can remain coherent for an infinite time even for a finite-length chain if the magnetic field is tuned to a value at which there is a level crossing. Furthermore, we show that the edge spins remain coherent for any initial state for the integrable case of a transverse field because all states have level crossings at the same value of the field, while the coherence time is increasingly large for lower temperatures in the case of a longitudinal field, which is nonintegrable.

Estimating migratory fish distribution from altitude and basin area: a case study in a large Neotropical river

Treesearch

Jose Ricardo Barradas; Lucas G. Silva; Bret C. Harvey; Nelson F. Fontoura

2012-01-01

1. The objective of this study was to identify longitudinal distribution patterns of large migratory fish species in the Uruguay River basin, southern Brazil, and construct statistical distribution models for Salminus brasiliensis, Prochilodus lineatus, Leporinus obtusidens and Pseudoplatystoma corruscans. 2. The sampling programme resulted in 202 interviews with old...

Measuring Executive Function in Early Childhood: A Case for Formative Measurement

ERIC Educational Resources Information Center

Willoughby, Michael T.; Blair, Clancy B.

2016-01-01

This study tested whether individual executive function (EF) tasks were better characterized as formative or reflective indicators of the latent construct of EF. EF data that were collected as part of the Family Life Project (FLP), a prospective longitudinal study of families who were recruited at the birth of a new child (N = 1,292), when…

Leading Entrepreneurial E-Learning Development in Legal Education: A Longitudinal Case Study of "Universities as Learning Organizations"

ERIC Educational Resources Information Center

Trevitt, Chris; Steed, Aliya; Du Moulin, Lynn; Foley, Tony

2017-01-01

Purpose: The study aims to review the entrepreneurial and educational innovations in technology-enabled distance education in practical legal education (PLE) accomplished by a unit "on the periphery" of a strong research-led university. It also aims to examine the learning organisation (LO) attributes associated with this initiative.…

Exploring Long-Term Productive Vocabulary Development in an EFL Context: The Role of Motivation

ERIC Educational Resources Information Center

Zheng, Yongyan

2012-01-01

The paper reports on a longitudinal multiple-case study that probed into four advanced university-level Chinese EFL learners' situated vocabulary learning experiences and explored the role of L2 motivation in their productive vocabulary development. In the study, Lexical Frequency Profile analysis and semi-structured interviews were conducted with…

Scaffolding during the Formal Assessment of Young EAL Learners: A New Zealand Case Study

ERIC Educational Resources Information Center

Booth, Dawn

2012-01-01

Despite growing interest in the theorisation of teacher-based assessment (TBA), very little research has paid close attention to how teachers practice assessment embedded in real classroom contexts. This longitudinal study over one school term reports on the TBA of young learners with English as an additional language (EAL) in New Zealand primary…

Lexical Complexity Development from Dynamic Systems Theory Perspective: Lexical Density, Diversity, and Sophistication

ERIC Educational Resources Information Center

Kalantari, Reza; Gholami, Javad

2017-01-01

This longitudinal case study explored Iranian EFL learners' lexical complexity (LC) through the lenses of Dynamic Systems Theory (DST). Fifty independent essays written by five intermediate to advanced female EFL learners in a TOEFL iBT preparation course over six months constituted the corpus of this study. Three Coh-Metrix indices (Graesser,…

Analyzing the School Evaluation Use Process To Make Evaluation Worth the Effort.

ERIC Educational Resources Information Center

Pechman, Ellen M.; King, Jean A.

This paper describes a structure for assessing the school evaluation use process developed from a longitudinal case study of districtwide and school level evaluation procedures in a large urban school district. Two fundamental questions guided the study: (1) Why isn't the evaluation process more useful to decision-makers and practitioners? and (2)…

Project VALOR: design and methods of a longitudinal registry of post-traumatic stress disorder (PTSD) in combat-exposed veterans in the Afghanistan and Iraqi military theaters of operations.

PubMed

Rosen, Raymond C; Marx, Brian P; Maserejian, Nancy N; Holowka, Darren W; Gates, Margaret A; Sleeper, Lynn A; Vasterling, Jennifer J; Kang, Han K; Keane, Terence M

2012-03-01

Few studies have investigated the natural history of post-traumatic stress disorder (PTSD). Project VALOR (Veterans' After-discharge Longitudinal Registry) was designed as a longitudinal patient registry assessing the course of combat-related PTSD among 1600 male and female Veterans who served in Operation Enduring Freedom (OEF) in Afghanistan or Operation Iraqi Freedom (OIF). Aims of the study include investigating patterns and predictors of progression or remission of PTSD and treatment utilization. The study design was based on recommendations from the Agency for Healthcare Quality and Research for longitudinal disease registries and used a pre-specified theoretical model to select the measurement domains for data collection and interpretation of forthcoming results. The registry will include 1200 male and female Veterans with a recent diagnosis of PTSD in the Department of Veteran Affairs (VA) electronic medical record and a comparison group of 400 Veterans without a medical record-based PTSD diagnosis, to also allow for case-control analyses. Data are collected from administrative databases, electronic medical records, a self-administered questionnaire, and a semi-structured diagnostic telephone interview. Project VALOR is a unique and timely registry study that will evaluate the clinical course of PTSD, psychosocial correlates, and health outcomes in a carefully selected cohort of returning OEF/OIF Veterans. Copyright © 2011 John Wiley & Sons, Ltd.

Transfer of the second to the first metatarsal ray in a case of lawn mower injury: a case report.

PubMed

Sassu, Paolo; Tsai, Tsu Min

2009-01-01

The medial longitudinal arch of the foot plays a major role for a physiologic transfer of the load from the heel to the forefoot during walking and running. Traumatic amputation that involve either the great toe or the whole first metatarsal bone can lead to collapse of the medial longitudinal arch, overload of the metatarsal heads, and painful callus formation. If replant of the amputated part is not possible or has failed, it is advisable to reconstruct the medial longitudinal arch in order to re-establish a functional transfer of the load in the foot. We present a case of a young lady who suffered from traumatic amputation at the distal third of the first metatarsal. Replantation failed due to the severity of the initial injury. Despite a good coverage of the defect with a lateral arm flap, the patient developed a painful plantar callus underneath the amputated stump. The adjacent second metatarsal ray was then raised as a pedicled flap including bone and soft tissues and transferred to the first ray in order to reconstruct a physiologic medial longitudinal arch. The patient had excellent functional results with no recurrence of the callus. (c) 2008 Wiley-Liss, Inc.

Reasons for Vocabulary Attrition: Revisiting the State of the Art

ERIC Educational Resources Information Center

Alharthi, Thamer

2015-01-01

This paper reports on a one year, mixed-methods longitudinal case study investigating the neglected area of the perceived reasons why participants forget vocabulary knowledge. The participants were 43 fourth year male Saudi EFL majors at King Abdulaziz University KAU, Saudi Arabia. Quantitative and qualitative data including self-reported…

Looking Beyond the Valley: A Five-Year Case Study of Course Innovation.

ERIC Educational Resources Information Center

Allen, Gary K.; Wedman, John F.; Folk, Lillian C.

2001-01-01

Examined longitudinal changes in student course evaluations throughout the process of implementing information technology-enhanced delivery of a veterinary immunology course. Found that student ratings of almost all aspects of the course and instruction declined significantly during the five-year period of technology implementation and then…

Differential Recognition of Children's Cultural Practices in Middle Primary Literacy Classrooms

ERIC Educational Resources Information Center

Nixon, Helen; Comber, Barbara

2006-01-01

This paper argues that teachers' recognition of children's cultural practices is an important positive step in helping socio-economically disadvantaged children engage with school literacies. Based on 21 longitudinal case studies of children's literacy development over a 3-year period, the authors demonstrate that when children's knowledges and…

A Chameleon with a Complex: Searching for Transformation in International Service-Learning

ERIC Educational Resources Information Center

Kiely, Richard

2004-01-01

This article reports findings from a longitudinal case study investigating how students experience perspective transformation from their participation in international service-learning program with an explicit social justice orientation. Findings indicate that each student experienced profound changes in their world-view in at least one of six…

Uncovering One Trilingual Child's Multi-Literacies Development across Informal and Formal Learning Contexts

ERIC Educational Resources Information Center

Kim, Mi Song

2016-01-01

Due to globalisation and rapid technological change, today's educators need to help students develop multi-literacy competencies to enable them to function successfully in our culturally and linguistically diverse (CLD) and increasingly connected global and digital society. A qualitative, longitudinal case study attempted to uncover the…

Mediating Factors in Literacy Instruction: How Novice Elementary Teachers Navigate New Teaching Contexts

ERIC Educational Resources Information Center

Scales, Roya Qualls; Wolsey, Thomas DeVere; Young, Janet; Smetana, Linda; Grisham, Dana L.; Lenski, Susan; Dobler, Elizabeth; Yoder, Karen Kreider; Chambers, Sandra A.

2017-01-01

This longitudinal study, framed by activity theory, examines what seven novice teachers' talk and actions reveal about their literacy teaching practices then delves into mediating influences of the teaching context. Utilizing collective, multi-case methods, data sources included interviews, observations, and artifacts. Findings indicate novices…

Are We Preparing or Training Teachers? Developing Professional Judgment in and beyond Teacher Preparation Programs

ERIC Educational Resources Information Center

Scales, Roya Q.; Wolsey, Thomas DeVere; Lenski, Susan; Smetana, Linda; Yoder, Karen K.; Dobler, Elizabeth; Grisham, Dana L.; Young, Janet R.

2018-01-01

This three phase longitudinal multiple-case study, framed by positioning theory, investigated how four novice teachers learned to use professional judgment in their literacy instruction. Data sources from coursework, student teaching, and novice teaching were included. Interviews, observations, researchers' observational notes, and school and…

Crossing the Chasm--Introducing Flexible Learning into the Botswana Technical Education Programme: From Policy to Action

ERIC Educational Resources Information Center

Richardson, Alison Mead

2009-01-01

This paper reports on a longitudinal, ethnomethodological case study of the development towards flexible delivery of the Botswana Technical Education Programme (BTEP), offered by Francistown College of Technical & Vocational Education (FCTVE). Data collection methods included documentary analysis, naturalistic participant observation, and…

Teacher-Led Change in Secondary School Physical Education

ERIC Educational Resources Information Center

Cameron, Jay; Mercier, Kevin; Doolittle, Sarah

2016-01-01

How and why meaningful curriculum or program changes happen in physical education is important, but not well understood, especially at the secondary school level. In this longitudinal case study, we examined teacher-initiated changes in a high school physical education program. Data were collected through prolonged engagement over 5 years and…

Proximal Participation: A Pathway into Work

ERIC Educational Resources Information Center

Chan, Selena

2013-01-01

In a longitudinal case study of apprentices, the term proximal participation was coined to describe the entry process of young people, with unclear career destinations, into the trade of baking. This article unravels the significance of proximal participation in the decision-making processes of young people who enter a trade through initial…

Contextualising ECEC Research: The Case of Slovenia

ERIC Educational Resources Information Center

Vidmar, Maša

2015-01-01

In the present study the longitudinal relations between quantity of centre-based child care (in months) and teacher reports of internalising and externalising behaviour in the first and second grades were examined for 325 Slovenian children. The socio-political context of affordable, accessible and homogenously high-quality child care is quite…

Learning Difficulty and Learner Identity: A Symbiotic Relationship

ERIC Educational Resources Information Center

Hirano, Eliana

2009-01-01

This paper reports on a longitudinal case study of an adult EFL learner who perceived himself as having difficulty learning English. Both learning difficulty and learner identity are viewed as being constructed in discursive interactions throughout one's life and, hence, amenable to reconstruction. Data collected from classroom interactions,…

Stemming the Diffusion of Responsibility: A Longitudinal Case Study of America's Chemistry Teachers

ERIC Educational Resources Information Center

Rushton, Gregory T.; Ray, Herman E.; Criswell, Brett A.; Polizzi, Samuel J.; Bearss, Clyde J.; Levelsmier, Nicholas; Chhita, Himanshu; Kirchhoff, Mary

2014-01-01

National initiatives to expand the aggregate science, technology, engineering, and math (STEM) workforce reflect America's goals to increase global competitiveness. However, the aggregation of STEM stakeholders may elicit a "diffusion of responsibility" because individuals assume others are already acting. Here, we perform a longitudinal…

The Development of Teacher Perspectives.

ERIC Educational Resources Information Center

Tabachnick, B. Robert; And Others

Two-year longitudinal case studes were conducted of four teachers, beginning with the student teaching experience through the first year of teaching. The study explored ways in which teaching perspectives, evidenced at the end of student teaching, are strengthened or modified during the first year of teaching. It also sought to determine who and…

Athletics and Academic Achievement in Latino Youth: A Cautionary Tale

ERIC Educational Resources Information Center

Chen, Wei; Harklau, Linda

2017-01-01

Participation in extracurricular activities has been associated with enhanced academic achievement in Latino youth. Based on a longitudinal case study of one immigrant adolescent, this article finds that athletic participation is in itself neither a wholly positive or negative influence on Latino school achievement. Rather, effects of…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, W.; Zhu, W. D.; Smith, S. A.

While structural damage detection based on flexural vibration shapes, such as mode shapes and steady-state response shapes under harmonic excitation, has been well developed, little attention is paid to that based on longitudinal vibration shapes that also contain damage information. This study originally formulates a slope vibration shape for damage detection in bars using longitudinal vibration shapes. To enhance noise robustness of the method, a slope vibration shape is transformed to a multiscale slope vibration shape in a multiscale domain using wavelet transform, which has explicit physical implication, high damage sensitivity, and noise robustness. These advantages are demonstrated in numericalmore » cases of damaged bars, and results show that multiscale slope vibration shapes can be used for identifying and locating damage in a noisy environment. A three-dimensional (3D) scanning laser vibrometer is used to measure the longitudinal steady-state response shape of an aluminum bar with damage due to reduced cross-sectional dimensions under harmonic excitation, and results show that the method can successfully identify and locate the damage. Slopes of longitudinal vibration shapes are shown to be suitable for damage detection in bars and have potential for applications in noisy environments.« less

Multiple time scale analysis of pressure oscillations in solid rocket motors

NASA Astrophysics Data System (ADS)

Ahmed, Waqas; Maqsood, Adnan; Riaz, Rizwan

2018-03-01

In this study, acoustic pressure oscillations for single and coupled longitudinal acoustic modes in Solid Rocket Motor (SRM) are investigated using Multiple Time Scales (MTS) method. Two independent time scales are introduced. The oscillations occur on fast time scale whereas the amplitude and phase changes on slow time scale. Hopf bifurcation is employed to investigate the properties of the solution. The supercritical bifurcation phenomenon is observed for linearly unstable system. The amplitude of the oscillations result from equal energy gain and loss rates of longitudinal acoustic modes. The effect of linear instability and frequency of longitudinal modes on amplitude and phase of oscillations are determined for both single and coupled modes. For both cases, the maximum amplitude of oscillations decreases with the frequency of acoustic mode and linear instability of SRM. The comparison of analytical MTS results and numerical simulations demonstrate an excellent agreement.

The "Nursing Home Compare" measure of urinary/fecal incontinence: cross-sectional variation, stability over time, and the impact of case mix.

PubMed

Li, Yue; Schnelle, John; Spector, William D; Glance, Laurent G; Mukamel, Dana B

2010-02-01

To assess the impact of facility case mix on cross-sectional variations and short-term stability of the "Nursing Home Compare" incontinence quality measure (QM) and to determine whether multivariate risk adjustment can minimize such impacts. Retrospective analyses of the 2005 national minimum data set (MDS) that included approximately 600,000 long-term care residents in over 10,000 facilities in each quarterly sample. Mixed logistic regression was used to construct the risk-adjusted QM (nonshrinkage estimator). Facility-level ordinary least-squares models and adjusted R(2) were used to estimate the impact of case mix on cross-sectional and short-term longitudinal variations of currently published and risk-adjusted QMs. At least 50 percent of the cross-sectional variation and 25 percent of the short-term longitudinal variation of the published QM are explained by facility case mix. In contrast, the cross-sectional and short-term longitudinal variations of the risk-adjusted QM are much less susceptible to case-mix variations (adjusted R(2)<0.10), even for facilities with more extreme or more unstable outcome. Current "Nursing Home Compare" incontinence QM reflects considerable case-mix variations across facilities and over time, and therefore it may be biased. This issue can be largely addressed by multivariate risk adjustment using risk factors available in the MDS.

Effectiveness and Value of Prophylactic 5-Layer Foam Sacral Dressings to Prevent Hospital-Acquired Pressure Injuries in Acute Care Hospitals: An Observational Cohort Study.

PubMed

Padula, William V

The purpose of this study was to examine the effectiveness and value of prophylactic 5-layer foam sacral dressings to prevent hospital-acquired pressure injury rates in acute care settings. Retrospective observational cohort. We reviewed records of adult patients 18 years or older who were hospitalized at least 5 days across 38 acute care hospitals of the University Health System Consortium (UHC) and had a pressure injury as identified by Patient Safety Indicator #3 (PSI-03). All facilities are located in the United States. We collected longitudinal data pertaining to prophylactic 5-layer foam sacral dressings purchased by hospital-quarter for 38 academic medical centers between 2010 and 2015. Longitudinal data on acute care, hospital-level patient outcomes (eg, admissions and PSI-03 and pressure injury rate) were queried through the UHC clinical database/resource manager from the Johns Hopkins Medicine portal. Data on volumes of dressings purchased per UHC hospital were merged with UHC data. Mixed-effects negative binomial regression was used to test the longitudinal association of prophylactic foam sacral dressings on pressure injury rates, adjusted for hospital case-mix and Medicare payments rules. Significant pressure injury rate reductions in US acute care hospitals between 2010 and 2015 were associated with the adoption of prophylactic 5-layer foam sacral dressings within a prevention protocol (-1.0 cases/quarter; P = .002) and changes to Medicare payment rules in 2014 (-1.13 cases/quarter; P = .035). Prophylactic 5-layer foam sacral dressings are an effective component of a pressure injury prevention protocol. Hospitals adopting these technologies should expect good value for use of these products.

Psychological stress and burnout in medical students: a five-year prospective longitudinal study.

PubMed Central

Guthrie, E; Black, D; Bagalkote, H; Shaw, C; Campbell, M; Creed, F

1998-01-01

The aim of this study was to assess psychological morbidity and symptoms of burnout in medical students during their undergraduate training, and to identify baseline factors that predict psychological morbidity in students in the final year of the course. It was a 5-year prospective longitudinal cohort study. Students were assessed in years 1, 4 and 5 of their medical undergraduate training by means of the GHQ-12 and the Maslach Burnout Inventory. 172 (84.3%), 157 (77.0%) and 155 (75.9%) students out of an original group of 204 completed assessments in years 1, 4 and 5, respectively. 18 students were above threshold on the GHQ-12 on all three occasions, 25 on two occasions and 43 on one occasion; 69 students were never a 'case'. Students who were cases on two or more occasions were more likely to find the medical course stressful during the first year, but not subsequent years. There was no significant difference between the percentages of men and women who scored as cases on the GHQ-12 in any of the years. The best predictor of psychological morbidity in the final year of the course was the GHQ-12 score in year 1. This study suggests that a small group of students repeatedly experience psychological distress during their medical training. PMID:9764076

Early Impairment of Cardiac Function and Asynchronization of Systemic Amyloidosis with Preserved Ejection Fraction Using Two-Dimensional Speckle Tracking Echocardiography.

PubMed

Huang, He; Jing, Xian-chao; Hu, Zhang-xue; Chen, Xi; Liu, Xiao-qin

2015-12-01

To observe the ventricular global and regional function of the patients with systemic amyloidosis using two-dimensional speckle tracking echocardiography. The study enrolled 31 consecutive biopsy-proved patients with systemic amyloidosis who underwent echocardiographic examination and EF ≥ 55% and 37 age- and gender-matched healthy controls. We compared systolic strain and strain rate, diastolic strain rate, time to peak strain, peak delay time in longitudinal, radial, circumferential directions in 16 left ventricular segments. The global peak systolic longitudinal and radial strain of left ventricle, peak systolic longitudinal strain and strain rate, diastolic strain rate of right ventricular free wall were also compared. (1) Global peak systolic longitudinal strain (GPSLS), peak systolic longitudinal strain (PSLS) and strain rate (PSLSR), peak early diastolic longitudinal strain rate (PELSR) in 16 segments were decreased in case (P < 0.05). (2) Peak systolic radial strain and strain rate of inferoseptum and inferolateral at the level of papillary muscle were lower (P < 0.05), and peak early diastolic radial strain rate (PERSR) was reduced (P < 0.05). (3) Peak early diastolic circumferential strain rate was lower (P < 0.05). (4) Time to peak systolic longitudinal, radial, circumferential strain was longer, and peak delay time at the same level retarded (P < 0.05). (5) Into right ventricular wall, PSLS and PSLSR at mid-segment, and PSLSR, PELSR, peak atrial systolic longitudinal strain rate (PALSR) at basal were reduced (P < 0.05). (6) Inverse correlation between interventricular septum (IVS) thickness and GPSLS and GPSRS was found (P < 0.05). Systolic and diastolic dysfunction existed in systemic amyloidosis with preserved EF. Mechanical contraction disorder may be one reason for systolic dysfunction. GPLSR and GPRSR were negatively related to IVS thickness. © 2015, Wiley Periodicals, Inc.

Prosecution of adult sexual assault cases: a longitudinal analysis of the impact of a sexual assault nurse examiner program.

PubMed

Campbell, Rebecca; Patterson, Debra; Bybee, Deborah

2012-02-01

Most sexual assaults are never reported to law enforcement, and even among reported cases, most will never be successfully prosecuted. This reality has been a long-standing source of frustration for survivors, victim advocates, as well as members of the criminal justice system. To address this problem, communities throughout the United States have implemented multidisciplinary response interventions to improve post-assault care for victims and increase reporting and prosecution rates. One such model is the Sexual Assault Nurse Examiner (SANE) program, whereby specially trained nurses (rather than hospital emergency department [ED] physicians) provide comprehensive psychological, medical, and forensic services for sexual assault victims. The purpose of this study was to examine whether adult sexual assault cases were more likely to be investigated and prosecuted after the implementation of a SANE program within a large Midwestern county. A quasi-experimental design was used to compare criminal justice system case progression pre-SANE to post-SANE. Results from longitudinal multilevel ordinal regression modeling revealed that case progression through the criminal justice system significantly increased pre- to post-SANE: more cases reached the "final" stages of prosecution (i.e., conviction at trial and/or guilty plea bargains) post-SANE. These findings are robust after accounting for changes in operation at the focal county prosecutors' office and seasonal variation in rape reporting. Implications for policy and practice are discussed.

Co-Evolution of User and Organizational Interfaces: A Longitudinal Case Study of WWW Dissemination of National Statistics.

ERIC Educational Resources Information Center

Marchionini, Gary

2002-01-01

Describes how user interfaces for the Bureau of Labor Statistics (BLS) web site evolved over a 5-year period along with the larger organizational interface and how this co-evolution has influenced the institution. Interviews with BLS staff and transaction log analysis are the foci of this study, as well as user information-seeking studies and user…

Predicting Disease Progression in Scleroderma with Skin and Blood Biomarkers

DTIC Science & Technology

2016-12-01

epidermal differentiation in addition to those involved in extracel- lular matrix production and myofibroblast contractility (35). In a followup study ...important manifestation of SSc are needed. Several studies have linked autoantibody production with genetics in SSc. Multiple polymorphisms in the human...longitudinal clinical data and genetic markers. GENISOS is an inception cohort that avoids survival bias inherent in studies of prevalent cases (mean disease

Thick Explanation in the Ethnographic Study of Child Socialization: A Longitudinal Study of the Problem of Schooling for Kwara'ae (Solomon Islands) Children.

ERIC Educational Resources Information Center

Watson-Gegeo, Karen Ann

1992-01-01

Outlines a framework for examining children's socialization that combines microlevels and macrolevels. Applies the framework to a case study of student failure in the Solomon Islands. Concludes that children's failure had less to do with home socialization than with larger societal processes that shape schooling in the Solomons. (MM)

Teaching Approaches of Beginning Teachers for Jewish Studies in Israeli "Mamlachti" Schools: A Case Study of a Jewish Education Teachers' Training Program for Outstanding Students

ERIC Educational Resources Information Center

Katzin, Ori

2015-01-01

This article presents findings from a longitudinal qualitative study that examined teaching approaches of neophyte teachers in Israel during their 4-year exclusive teachers' training program for teaching Jewish subjects and first two years of teaching. The program wanted to promote change in secular pupils' attitudes toward Jewish subjects. We…

Posttraumatic stress disorder among parents of children on cancer treatment: a longitudinal study.

PubMed

Pöder, Ulrika; Ljungman, Gustaf; von Essen, Louise

2008-05-01

The main aim of this study was to investigate the occurrence of cancer-related posttraumatic stress disorder (PTSD) among parents of children on cancer treatment. A longitudinal design with assessments at one week (T1), two (T2), and four (T3) months after the child's diagnosis was used. Two hundred and fourteen parents (107 mothers, 107 fathers) participated at T1-T3. The PTSD Checklist Civilian (PCL-C), a self-report screening instrument for PTSD, was answered by parents over the telephone. According to the PCL-C symptom criteria method 33%, more mothers than fathers, score as potential cases of acute stress disorder (ASD) at T1, whereas 28% as potential cases of PTSD at T2 and 22% at T3. The levels of acute- and posttraumatic stress symptoms show a linear, descending pattern, and mothers report higher levels than fathers. Half of the parents who score as potential cases of ASD a week after the child's diagnosis score as potential cases of PTSD four months later. The findings illustrate that a group of parents of children with cancer experience serious psychological distress related to their child's disease. A traumatic stress perspective on childhood cancer should be applied to paediatric oncology care and appropriate psychosocial interventions should be offered to parents when needed. (c) 2007 John Wiley & Sons, Ltd.

CD133 expression in oral lichen planus correlated with the risk for progression to oral squamous cell carcinoma.

PubMed

Sun, Lili; Feng, Jinqiu; Ma, Lihua; Liu, Wei; Zhou, Zengtong

2013-12-01

Oral lichen planus (OLP) is a potentially malignant disorder associated with an increased risk for progression to oral squamous cell carcinoma (OSCC). The objective of this study to determine protein expression of cancer stem cell marker CD133 in tissue samples of patients with OLP and evaluate the correlation between CD133 expression and the risk of progression to OSCC. In this longitudinal case-control study, a total of 110 patients with OLP who received a mean follow-up of 56 months were enrolled, including 100 patients who did not progress to OSCC and 10 patients who had progressed to OSCC. CD133 expression was determined using immunohistochemistry in samples from these patients. Analysis of 10 cases of normal oral mucosa and 6 cases of postmalignant OSCC form previously diagnosed OLP was also performed. The results showed that CD133 expression was observed in 29% cases of nonprogressing OLP and in 80% cases of progressing OLP (P = .002). CD133 was not expressed in normal oral mucosa, but it positively expressed in the 100% cases of OSCC. Logistic regression analysis revealed that the risk of malignant progression in the patients with CD133-positive expression was significantly higher than those with CD133 negativity (odds ratio, 9.79; 95% confidence interval, 1.96-48.92; P = .005). Collectively, CD133 expression was significantly associated with malignant progression in a longitudinal series of patients with OLP. Our findings suggested that CD133 may serve as a novel candidate biomarker for risk assessment of malignant potential of OLP. © 2013.

Graduates in Economics and Educational Mismatch: The Case Study of the University of Naples "Parthenope"

ERIC Educational Resources Information Center

Quintano, Claudio; Castellano, Rosalia; D'Agostino, Antonella

2008-01-01

The quality of jobs of economics graduates was studied in terms of educational mismatch. The returns of over-education on earnings and on the job-search were also investigated. The discussion regards the second wave of a longitudinal survey of a random sample of economics graduates from the University of Naples "Parthenope", a major…

Shared Values as Anchors of a Learning Community: A Case Study in Information Systems Design

ERIC Educational Resources Information Center

Giordano, Daniela

2004-01-01

This paper examines the role in both individual and organizational learning of the system of values sustained by a community undertaking a design task. The discussion is based on the results of a longitudinal study of a community of novice information system designers supported by a Web-based shared design memory which allows reuse of design…

Investigation of Coefficient of Individual Agreement in Terms of Sample Size, Random and Monotone Missing Ratio, and Number of Repeated Measures

ERIC Educational Resources Information Center

Temel, Gülhan Orekici; Erdogan, Semra; Selvi, Hüseyin; Kaya, Irem Ersöz

2016-01-01

Studies based on longitudinal data focus on the change and development of the situation being investigated and allow for examining cases regarding education, individual development, cultural change, and socioeconomic improvement in time. However, as these studies require taking repeated measures in different time periods, they may include various…

Enhancing Adherence among Older African American Men Enrolled in a Longitudinal Cancer Screening Trial

ERIC Educational Resources Information Center

Ford, Marvella E.; Havstad, Suzanne; Vernon, Sally W.; Davis, Shawna D.; Kroll, David; Lamerato, Lois; Swanson, G. Marie

2006-01-01

Purpose: The purpose of this study was to enhance adherence among older (aged 55 years and older) African American men enrolled in a cancer screening trial for prostate, lung, and colorectal cancer. For this study, we defined "adherence" as completing the trial screenings. Design and Methods: We used a randomized trial design. Case managers…

The Fluctuating Development of Cross-Linguistic Semantic Awareness: A Longitudinal Multiple-Case Study

ERIC Educational Resources Information Center

Zheng, Yongyan

2014-01-01

Second language (L2) learners' awareness of first language-second language (L1-L2) semantic differences plays a critical role in L2 vocabulary learning. This study investigates the long-term development of eight university-level Chinese English as a foreign language learners' cross-linguistic semantic awareness over the course of 10 months. A…

Undergraduate Students' Ownership of Musical Learning: Obstacles and Options in One-to-One Teaching

ERIC Educational Resources Information Center

Johansson, Karin

2013-01-01

This paper describes a longitudinal, collaborative case study, made in the framework of the project Students' Ownership of Learning (SOL) during one academic year with one vocal teacher and two female students. The aim of the study was to relate the interaction between the teacher's and the students' intentions and expectations to…

Working at a Different Level? Curriculum Differentiation in Irish Lower Secondary Education

ERIC Educational Resources Information Center

Smyth, Emer

2018-01-01

Young people in Irish schools are required to choose whether to sit secondary exam subjects at higher or ordinary level. This paper draws on a mixed methods longitudinal study of students in 12 case-study schools to trace the factors influencing take-up of higher level subjects within lower secondary education. School organisation and process are…

A Test of Leading Explanations for the College Racial-Ethnic Achievement Gap: Evidence from a Longitudinal Case Study

ERIC Educational Resources Information Center

Martin, Nathan D.; Spenner, Kenneth I; Mustillo, Sarah A.

2017-01-01

In this study, we examined racial/ethnic differences in grade point average (GPA) among students at a highly selective, private university who were surveyed before matriculation and during the first, second and fourth college years, and assessed prominent explanations for the Black-White and Latino-White college achievement gap. We found that…

Multicompetence in L2 Language Play: A Longitudinal Case Study

ERIC Educational Resources Information Center

Bell, Nancy; Skalicky, Stephen; Salsbury, Tom

2014-01-01

Humor and language play have been recognized as important aspects of second language (L2) development. Qualitative studies that have documented the forms and functions of language play for adult and child L2 users have taken place largely in classroom settings. In order to gain a fuller understanding of such creative manipulations by L2 users, it…

Growing Up: School, Family, and Area Influences on Adolescents' Later Life Chances. CASE Discussion Paper.

ERIC Educational Resources Information Center

Burgess, Simon; Gardiner, Karen; Propper, Carol

This study explored the relationships between adult economic outcomes and three key factors during adolescence: schooling, family background, and county of residence. The empirical analysis was based on data covering the period from 1979-1996. Data came from the 1979 National Longitudinal Survey of Youth. The study examined a sample of people ages…

The Role of Parental Leadership in Academic Performance: A Case of Pupils in the Free Primary Education Program in Kenya

ERIC Educational Resources Information Center

Bellon, Emmanuel O.; Ngware, Moses Waithanji; Admassu, Kassahun

2017-01-01

The study examines the combined effects of key elements in parental leadership on academic performance. In the wake of inadequate learning resources, parental leadership becomes an indispensable learning input for children's academic performance. The discourse utilized data collected from 2005 to 2010 in a longitudinal study involving 1,549…

Girls' Participation in Physics in Single Sex Classes in Mixed Schools in Relation to Confidence and Achievement.

ERIC Educational Resources Information Center

Gillibrand, Eileen; Robinson, Peter; Brawn, Richard; Osborn, Albert

1999-01-01

Reports the findings from a three-year longitudinal case study of two single-sex General Certificate of Secondary Education (GCSE) physics classes in a mixed comprehensive school in England. Results indicate that girls who elected to study physics in single-sex classes gain confidence in the subject. This gain in confidence is associated with…

From Attila the Hun to Mary Had a Little Lamb: Redefining Principal Roles in Restructured Schools.

ERIC Educational Resources Information Center

Hallinger, Philip; Hausman, Charles

American policymakers have come to view principals as linchpins in plans for educational change. Findings of a study that examined how the principal's role changes in a school that is engaged in fundamental restructuring are presented in this paper. Data for the longitudinal case study of a suburban-urban school district in the northeastern United…

A Case Study in Effectively Bridging the Business Skills Gap for the Information Technology Professional

ERIC Educational Resources Information Center

Gorman, Michael F.

2011-01-01

A longitudinal study of information technology (IT) managers at a Fortune 200 company in the Southwest United States was conducted to assess the effectiveness of a training program at bridging the perceived business skills gap for IT employees. A needs assessment was carried out, resulting in a 4-module training program. The program was evaluated…

Child and adolescent psychiatry patients coming of age: a retrospective longitudinal study of inpatient treatment in Tyrol.

PubMed

Fuchs, Martin; Kemmler, Georg; Steiner, Hans; Marksteiner, Josef; Haring, Christian; Miller, Carl; Hausmann, Armand; Sevecke, Kathrin

2016-07-08

Mental illness is a common phenomenon at all ages. Various independent studies have shown that psychopathology is often expressed on a continuum from youth to adulthood. The aim of our study was to demonstrate a) the frequency of admission of former child and adolescent psychiatry inpatients (CAP-IP) to adult inpatient mental health facilities, and b) a potential longitudinal diagnostic shift. This is the first Austrian study designed to shed light on these issues. Nearly 1000 inpatient cases at a specialized child and adolescent care center were analyzed. These cases were then tracked using data matching with registry data from adult psychiatric institutions. Overall, our observational period was 23 years. 26 % of our sample of former CAP-IP used psychiatric inpatient mental health services as adults, thus indicating chronicity or reoccurrence. In line with previous literature, there were patients who stayed in the same diagnostic category as well as patients with a diagnostic shift from childhood to adulthood. Childhood and adolescence is a very important period for early intervention and prevention of mental illness. Our findings support the notion of the continuity of psychopathology from youth into adulthood.

The real-world problem of care coordination: a longitudinal qualitative study with patients living with advanced progressive illness and their unpaid caregivers.

PubMed

Daveson, Barbara A; Harding, Richard; Shipman, Cathy; Mason, Bruce L; Epiphaniou, Eleni; Higginson, Irene J; Ellis-Smith, Clare; Henson, Lesley; Munday, Dan; Nanton, Veronica; Dale, Jeremy R; Boyd, Kirsty; Worth, Allison; Barclay, Stephen; Donaldson, Anne; Murray, Scott

2014-01-01

To develop a model of care coordination for patients living with advanced progressive illness and their unpaid caregivers, and to understand their perspective regarding care coordination. A prospective longitudinal, multi-perspective qualitative study involving a case-study approach. Serial in-depth interviews were conducted, transcribed verbatim and then analyzed through open and axial coding in order to construct categories for three cases (sites). This was followed by continued thematic analysis to identify underlying conceptual coherence across all cases in order to produce one coherent care coordination model. Fifty-six purposively sampled patients and 27 case-linked unpaid caregivers. Three cases from contrasting primary, secondary and tertiary settings within Britain. Coordination is a deliberate cross-cutting action that involves high-quality, caring and well-informed staff, patients and unpaid caregivers who must work in partnership together across health and social care settings. For coordination to occur, it must be adequately resourced with efficient systems and services that communicate. Patients and unpaid caregivers contribute substantially to the coordination of their care, which is sometimes volunteered at a personal cost to them. Coordination is facilitated through flexible and patient-centered care, characterized by accurate and timely information communicated in a way that considers patients' and caregivers' needs, preferences, circumstances and abilities. Within the midst of advanced progressive illness, coordination is a shared and complex intervention involving relational, structural and information components. Our study is one of the first to extensively examine patients' and caregivers' views about coordination, thus aiding conceptual fidelity. These findings can be used to help avoid oversimplifying a real-world problem, such as care coordination. Avoiding oversimplification can help with the development, evaluation and implementation of real-world coordination interventions for patients and their unpaid caregivers in the future.

Clinical implications of the proposed ICD-11 PTSD diagnostic criteria.

PubMed

Barbano, Anna C; van der Mei, Willem F; Bryant, Richard A; Delahanty, Douglas L; deRoon-Cassini, Terri A; Matsuoka, Yutaka J; Olff, Miranda; Qi, Wei; Ratanatharathorn, Andrew; Schnyder, Ulrich; Seedat, Soraya; Kessler, Ronald C; Koenen, Karestan C; Shalev, Arieh Y

2018-05-14

Projected changes to post-traumatic stress disorder (PTSD) diagnostic criteria in the upcoming International Classification of Diseases (ICD)-11 may affect the prevalence and severity of identified cases. This study examined differences in rates, severity, and overlap of diagnoses using ICD-10 and ICD-11 PTSD diagnostic criteria during consecutive assessments of recent survivors of traumatic events. The study sample comprised 3863 survivors of traumatic events, evaluated in 11 longitudinal studies of PTSD. ICD-10 and ICD-11 diagnostic rules were applied to the Clinician-Administered PTSD Scale (CAPS) to derive ICD-10 and ICD-11 diagnoses at different time intervals between trauma occurrence and 15 months. The ICD-11 criteria identified fewer cases than the ICD-10 across assessment intervals (range -47.09% to -57.14%). Over 97% of ICD-11 PTSD cases met concurrent ICD-10 PTSD criteria. PTSD symptom severity of individuals identified by the ICD-11 criteria (CAPS total scores) was 31.38-36.49% higher than those identified by ICD-10 criteria alone. The latter, however, had CAPS scores indicative of moderate PTSD. ICD-11 was associated with similar or higher rates of comorbid mood and anxiety disorders. Individuals identified by either ICD-10 or ICD-11 shortly after traumatic events had similar longitudinal course. This study indicates that significantly fewer individuals would be diagnosed with PTSD using the proposed ICD-11 criteria. Though ICD-11 criteria identify more severe cases, those meeting ICD-10 but not ICD-11 criteria remain in the moderate range of PTSD symptoms. Use of ICD-11 criteria will have critical implications for case identification in clinical practice, national reporting, and research.

Assessment of regional systolic and diastolic myocardial function using tissue Doppler and strain imaging in dogs with dilated cardiomyopathy.

PubMed

Chetboul, Valérie; Gouni, Vassiliki; Sampedrano, Carolina Carlos; Tissier, Renaud; Serres, François; Pouchelon, Jean-Louis

2007-01-01

Tissue Doppler Imaging (TDI) or strain (St) imaging could provide sensitive indices for early detection and treatment follow-up of canine dilated cardiomyopathy (DCM). Analysis of TDI and St features in dogs with overt DCM is a prerequisite before using these new criteria in prospective screenings of predisposed families or in clinical trials. Radial and longitudinal right and left myocardial motion, assessed by TDI and St variables, is altered in dogs with DCM. Case records for 26 dogs; 14 with DCM and 12 healthy controls of comparable age and weight were reviewed. A retrospective analysis was conducted of conventional echocardiography, 2-dimensional color TDI, and St imaging data. The DCM group was characterized by decreases in radial and longitudinal systolic velocity gradients of the left ventricular free wall (LVFW), radial and longitudinal absolute values of peak systolic St of the LVFW, and longitudinal systolic right ventricular (RV) velocities (all P < .001 versus control) associated with longitudinal postsystolic contraction waves in 7/14 dogs. Early diastolic LVFW velocities also were decreased for longitudinal (P < .01) and radial (P < .05) motions. All radial LVFW, longitudinal basal LVFW, and RV systolic velocities were negatively correlated with heart rate (P < .01). LV contractility along both the short and long axes is impaired in dogs with spontaneous DCM, as is systolic RV and diastolic LVFW function. These myocardial alterations are associated with an inverse force-frequency relationship. Studies now are needed to determine the comparative sensitivity of TDI and St variables for the early detection of canine DCM.

New Methods to Address Old Challenges: The Use of Administrative Data for Longitudinal Replication Studies of Child Maltreatment

PubMed Central

Hurren, Emily; Stewart, Anna; Dennison, Susan

2017-01-01

Administrative data are crucial to the “big data” revolution of social science and have played an important role in the development of child maltreatment research. These data are also of value to administrators, policy makers, and clinicians. The focus of this paper is the use of administrative data to produce and replicate longitudinal studies of child maltreatment. Child protection administrative data have several advantages. They are often population-based, and allow longitudinal examination of child maltreatment and complex multi-level analyses. They also allow comparison across subgroups and minority groups, remove burden from individuals to disclose traumatic experiences, and can be less biased than retrospective recall. Finally, they can be linked to data from other agencies to explore comorbidity and outcomes, and are comparatively cost and time effective. The benefits and challenges associated with the use of administrative data for longitudinal child maltreatment research become magnified when these data are used to produce replications. Techniques to address challenges and support future replication efforts include developing a biographical understanding of the systems from which the data are drawn, using multiple data sources to contextualize the data and research results, recognizing and adopting various approaches to replication, and documenting all data coding and manipulation processes. These techniques are illustrated in this paper via a case study of previous replication work. PMID:28914775

New Methods to Address Old Challenges: The Use of Administrative Data for Longitudinal Replication Studies of Child Maltreatment.

PubMed

Hurren, Emily; Stewart, Anna; Dennison, Susan

2017-09-15

Administrative data are crucial to the "big data" revolution of social science and have played an important role in the development of child maltreatment research. These data are also of value to administrators, policy makers, and clinicians. The focus of this paper is the use of administrative data to produce and replicate longitudinal studies of child maltreatment. Child protection administrative data have several advantages. They are often population-based, and allow longitudinal examination of child maltreatment and complex multi-level analyses. They also allow comparison across subgroups and minority groups, remove burden from individuals to disclose traumatic experiences, and can be less biased than retrospective recall. Finally, they can be linked to data from other agencies to explore comorbidity and outcomes, and are comparatively cost and time effective. The benefits and challenges associated with the use of administrative data for longitudinal child maltreatment research become magnified when these data are used to produce replications. Techniques to address challenges and support future replication efforts include developing a biographical understanding of the systems from which the data are drawn, using multiple data sources to contextualize the data and research results, recognizing and adopting various approaches to replication, and documenting all data coding and manipulation processes. These techniques are illustrated in this paper via a case study of previous replication work.

The effect of the masses of the controls on the longitudinal stability with free elevator. Part I

NASA Technical Reports Server (NTRS)

Schmidt, Rudolf

1939-01-01

In the present report, aerodynamic relations under the effect of the weight moments are investigated, and an example given of the computation of the stability for a practical case. Later, the effects of the masses of the controls on the dynamic longitudinal stability will be considered.

Impact of missing data strategies in studies of parental employment and health: Missing items, missing waves, and missing mothers.

PubMed

Nguyen, Cattram D; Strazdins, Lyndall; Nicholson, Jan M; Cooklin, Amanda R

2018-07-01

Understanding the long-term health effects of employment - a major social determinant - on population health is best understood via longitudinal cohort studies, yet missing data (attrition, item non-response) remain a ubiquitous challenge. Additionally, and unique to the work-family context, is the intermittent participation of parents, particularly mothers, in employment, yielding 'incomplete' data. Missing data are patterned by gender and social circumstances, and the extent and nature of resulting biases are unknown. This study investigates how estimates of the association between work-family conflict and mental health depend on the use of four different approaches to missing data treatment, each of which allows for progressive inclusion of more cases in the analyses. We used 5 waves of data from 4983 mothers participating in the Longitudinal Study of Australian Children. Only 23% had completely observed work-family conflict data across all waves. Participants with and without missing data differed such that complete cases were the most advantaged group. Comparison of the missing data treatments indicate the expected narrowing of confidence intervals when more sample were included. However, impact on the estimated strength of association varied by level of exposure: At the lower levels of work-family conflict, estimates strengthened (were larger); at higher levels they weakened (were smaller). Our results suggest that inadequate handling of missing data in extant longitudinal studies of work-family conflict and mental health may have misestimated the adverse effects of work-family conflict, particularly for mothers. Considerable caution should be exercised in interpreting analyses that fail to explore and account for biases arising from missing data. Copyright © 2018. Published by Elsevier Ltd.

The Role of Socioeconomic Status in Longitudinal Trends of Cholera in Matlab, Bangladesh, 1993–2007

PubMed Central

Root, Elisabeth Dowling; Rodd, Joshua; Yunus, Mohammad; Emch, Michael

2013-01-01

There has been little evidence of a decline in the global burden of cholera in recent years as the number of cholera cases reported to WHO continues to rise. Cholera remains a global threat to public health and a key indicator of lack of socioeconomic development. Overall socioeconomic development is the ultimate solution for control of cholera as evidenced in developed countries. However, most research has focused on cross-county comparisons so that the role of individual- or small area-level socioeconomic status (SES) in cholera dynamics has not been carefully studied. Reported cases of cholera in Matlab, Bangladesh have fluctuated greatly over time and epidemic outbreaks of cholera continue, most recently with the introduction of a new serotype into the region. The wealth of longitudinal data on the population of Matlab provides a unique opportunity to explore the impact of socioeconomic status and other demographic characteristics on the long-term temporal dynamics of cholera in the region. In this population-based study we examine which factors impact the initial number of cholera cases in a bari at the beginning of the 0139 epidemic and the factors impacting the number of cases over time. Cholera data were derived from the ICDDR,B health records and linked to socioeconomic and geographic data collected as part of the Matlab Health and Demographic Surveillance System. Longitudinal zero-inflated Poisson (ZIP) multilevel regression models are used to examine the impact of environmental and socio-demographic factors on cholera counts across baris. Results indicate that baris with a high socioeconomic status had lower initial rates of cholera at the beginning of the 0139 epidemic (γ01 = −0.147, p = 0.041) and a higher probability of reporting no cholera cases (α01 = 0.156, p = 0.061). Populations in baris characterized by low SES are more likely to experience higher cholera morbidity at the beginning of an epidemic than populations in high SES baris. PMID:23326618

Case file coding of child maltreatment: Methods, challenges, and innovations in a longitudinal project of youth in foster care.

PubMed

Huffhines, Lindsay; Tunno, Angela M; Cho, Bridget; Hambrick, Erin P; Campos, Ilse; Lichty, Brittany; Jackson, Yo

2016-08-01

State social service agency case files are a common mechanism for obtaining information about a child's maltreatment history, yet these documents are often challenging for researchers to access, and then to process in a manner consistent with the requirements of social science research designs. Specifically, accessing and navigating case files is an extensive undertaking, and a task that many researchers have had to maneuver with little guidance. Even after the files are in hand and the research questions and relevant variables have been clarified, case file information about a child's maltreatment exposure can be idiosyncratic, vague, inconsistent, and incomplete, making coding such information into useful variables for statistical analyses difficult. The Modified Maltreatment Classification System (MMCS) is a popular tool used to guide the process, and though comprehensive, this coding system cannot cover all idiosyncrasies found in case files. It is not clear from the literature how researchers implement this system while accounting for issues outside of the purview of the MMCS or that arise during MMCS use. Finally, a large yet reliable file coding team is essential to the process, however, the literature lacks training guidelines and methods for establishing reliability between coders. In an effort to move the field toward a common approach, the purpose of the present discussion is to detail the process used by one large-scale study of child maltreatment, the Studying Pathways to Adjustment and Resilience in Kids (SPARK) project, a longitudinal study of resilience in youth in foster care. The article addresses each phase of case file coding, from accessing case files, to identifying how to measure constructs of interest, to dealing with exceptions to the coding system, to coding variables reliably, to training large teams of coders and monitoring for fidelity. Implications for a comprehensive and efficient approach to case file coding are discussed.

Case file coding of child maltreatment: Methods, challenges, and innovations in a longitudinal project of youth in foster care☆

PubMed Central

Huffhines, Lindsay; Tunno, Angela M.; Cho, Bridget; Hambrick, Erin P.; Campos, Ilse; Lichty, Brittany; Jackson, Yo

2016-01-01

State social service agency case files are a common mechanism for obtaining information about a child’s maltreatment history, yet these documents are often challenging for researchers to access, and then to process in a manner consistent with the requirements of social science research designs. Specifically, accessing and navigating case files is an extensive undertaking, and a task that many researchers have had to maneuver with little guidance. Even after the files are in hand and the research questions and relevant variables have been clarified, case file information about a child’s maltreatment exposure can be idiosyncratic, vague, inconsistent, and incomplete, making coding such information into useful variables for statistical analyses difficult. The Modified Maltreatment Classification System (MMCS) is a popular tool used to guide the process, and though comprehensive, this coding system cannot cover all idiosyncrasies found in case files. It is not clear from the literature how researchers implement this system while accounting for issues outside of the purview of the MMCS or that arise during MMCS use. Finally, a large yet reliable file coding team is essential to the process, however, the literature lacks training guidelines and methods for establishing reliability between coders. In an effort to move the field toward a common approach, the purpose of the present discussion is to detail the process used by one large-scale study of child maltreatment, the Studying Pathways to Adjustment and Resilience in Kids (SPARK) project, a longitudinal study of resilience in youth in foster care. The article addresses each phase of case file coding, from accessing case files, to identifying how to measure constructs of interest, to dealing with exceptions to the coding system, to coding variables reliably, to training large teams of coders and monitoring for fidelity. Implications for a comprehensive and efficient approach to case file coding are discussed. PMID:28138207

Teacher Learning during Transition from Pre-Service to Novice EFL Teacher: A Longitudinal Case Study

ERIC Educational Resources Information Center

Bulut Albaba, Melike

2017-01-01

In language teacher education literature, attention is predominantly centered on the content of teacher learning and cognition. The process of teacher learning and cognitive change over time remains relatively underexplored. For instance, despite its importance in career trajectory, there is limited empirical evidence on the transition process…

Sustaining Online Teacher Professional Development through Community Design

ERIC Educational Resources Information Center

Henderson, Michael

2007-01-01

Purpose: The purpose of this paper is to explore the role of community of practice in sustaining teachers' participation in a blended (face-to-face and online) professional development course. Design/methodology/approach: A longitudinal multiple-case study methodology was used in researching groups of five teachers in Australia and four teachers…

Social Capital and the Role of Trust in Aspirations for Higher Education

ERIC Educational Resources Information Center

Fuller, Carol

2014-01-01

This paper considers the role of social capital in the aspirations for higher education of a group of socially disadvantaged girls. Drawing on data from a longitudinal, ethnographic case study of an underperforming secondary school, the paper considers current conceptualisations of social capital and its role in educational ambitions. The paper…

A Longitudinal Perspective of Early Career Music Teachers: Contexts, Interactions, and Possible Selves

ERIC Educational Resources Information Center

Dabback, William

2018-01-01

The purpose of this multiple case study was to follow the development of three music educators during their student teaching semesters and into the first years of their careers. Possible selves theory provided a framework for exploring the links between cognition, expectations, and motivation. Interviewees negotiated their social and physical…

Teachers' Nascent Praxes of Care: Potentially Decolonizing Approaches to School Violence in Trinidad

ERIC Educational Resources Information Center

Williams, Hakim Mohandas Amani

2017-01-01

Zero tolerance, punitive, and more negative peace-oriented approaches dominate school violence interventions, despite research indicating that comprehensive approaches are more sustainable. In this article, I use data from a longitudinal case study at a Trinidadian secondary school to focus on the role of teachers and their impact on school…

Tracking Adult Literacy Acquisition with Functional MRI: A Single-Case Study

ERIC Educational Resources Information Center

Braga, Lucia W.; Amemiya, Eduardo; Tauil, Alexandre; Suguieda, Denis; Lacerda, Carolina; Klein, Elise; Dehaene-Lambertz, Ghislaine; Dehaene, Stanislas

2017-01-01

We evaluated neuro-functional changes associated with late acquisition of reading in an illiterate adult who underwent 20 longitudinal functional magnetic resonance imaging (fMRI) scans during 2 years, while the participant progressed from complete illiteracy to a modest level of alphabetical decoding. Initially, the participant did not activate…

A Tale of Three Sisters: Language Ideologies, Identities, and Negotiations in a Bilingual, Transnational Family

ERIC Educational Resources Information Center

King, Kendall A.

2013-01-01

This longitudinal case study investigated how linguistic identity was constructed, constrained, and performed by three sisters, aged 1, 12, and 17, within one bilingual, transnational Ecuadorian-U.S. family. Data were collected over 14 months through weekly home visits that included participant observation, informal interviews, and…

Shaping (Reflexive) Professional Identities across an Undergraduate Degree Programme: A Longitudinal Case Study

ERIC Educational Resources Information Center

Ryan, Mary; Carmichael, Mary-Ann

2016-01-01

In our complex and incongruous professional worlds, where there is no blueprint for dealing with unpredictable people and events, it is imperative that individuals develop reflexive approaches to professional identity building. Notwithstanding the importance of disciplinary knowledge and skills, higher education has a crucial role to play in…

Dynamic Development in Speaking versus Writing in Identical Twins

ERIC Educational Resources Information Center

Chan, HuiPing; Verspoor, Marjolijn; Vahtrick, Louisa

2015-01-01

Taking a dynamic usage-based perspective, this longitudinal case study compares the development of sentence complexity in speaking versus writing in two beginner Taiwanese learners of English (identical twins) in an extensive corpus consisting of 100 oral and 100 written texts of approximately 200 words produced by each twin over 8 months. Three…

One Shot Wonders Don't Work: A Causal-Comparative Case Study.

ERIC Educational Resources Information Center

Bramwell, K.; Forrester, S.; Houle, B.; Larocque, J.; Villeneuve, L.; Priest, S.

1997-01-01

A company division of 72 people that had participated in an adventure training program one year earlier was surveyed to identify the longitudinal impacts of adventure training on corporate managers, attitudes toward adventure training, and changes in work behavior. Results showed positive changes that were short-lived without follow-up programs.…

Influencing Science Teaching Self-Efficacy Beliefs of Primary School Teachers: A Longitudinal Case Study

ERIC Educational Resources Information Center

McKinnon, Merryn; Lamberts, Rod

2014-01-01

The science teaching self-efficacy beliefs of primary school teachers influence teaching practice. The purpose of this research was to determine if informal education institutions, such as science centres, could provide professional development that influences the science teaching self-efficacy beliefs of pre-service and in-service primary school…

Action and Thought in Cello Playing: An Investigation of Children's Practice and Performance

ERIC Educational Resources Information Center

Lisboa, Tania

2008-01-01

This article presents a longitudinal case study investigation of three young cellists' self-directed preparation of a new piece of music for an informal performance. The investigation considers how musical understanding starts to emerge in children's practice and performance. It explores practice at early stages of learning and examines the…

Twice Considered: Charter Schools and Student Achievement in Utah

ERIC Educational Resources Information Center

Ni, Yongmei; Rorrer, Andrea K.

2012-01-01

A relatively small state, Utah presents an interesting case to study charter schools given its friendly policy environment and its significant growth in charter school enrollment. Based on longitudinal student-level data from 2004 to 2009, this paper utilizes two approaches to evaluate the Utah charter school effectiveness: (a) hierarchical linear…

Successful Students' Negotiation of Township Schooling in Contemporary South Africa

ERIC Educational Resources Information Center

Kapp, Rochelle; Badenhorst, Elmi; Bangeni, Bongi; Craig, Tracy S.; van Rensburg, Viki Janse; Le Roux, Kate; Prince, Robert; Pym, June; van Pletzen, Ermien

2014-01-01

This article draws on data from a larger longitudinal qualitative case study which is tracking the progress of students over the course of their undergraduate degrees at a South African university. For this paper, we used background questionnaires and semi-structured interviews with 62 first-year students from working-class, township schools who…

The Implications of Bank-Issued Check Surveys for Evaluators: A Case Study

ERIC Educational Resources Information Center

Blair, Jason; Taylor, Ted K.; Johnson-Shelton, Deborah

2007-01-01

This article describes an innovative data collection procedure. A subsample (n = 164) of a longitudinal research project was assessed using a bank-issued check survey procedure (a removable bank check on which response fields were printed). Using the new procedure, parents returned their surveys simply by depositing or cashing their incentive…

Teachers Developing Exemplary Inquiry Practices: Three Longitudinal Case Studies

ERIC Educational Resources Information Center

Sweetman, Sara Berry

2013-01-01

If students are to be successful in the ever-changing scientific world they need to be taught how to think critically, to manipulate materials, and to gather evidence to build knowledge. Most teachers fall short in providing students the inquiry instruction described in the Next Generation Science Frameworks (National Research Council, 2011). This…

Graduate Development, Discursive Resources and the Employment Relationship at BAE Systems

ERIC Educational Resources Information Center

Jenner, Shirley

2008-01-01

Purpose: The purpose of this paper is to examine the evolution of an employee opinion survey and to evaluate its impact on the graduate training programme and associated employment relationships. Design/methodology/approach: The paper provides a detailed, longitudinal case study of one large-scale UK organisation. The approach recognises that…

The Effect of Neurolinguistic Programming on Organisational and Individual Performance: A Case Study.

ERIC Educational Resources Information Center

Thompson, John E.; Courtney, Lisa; Dickson, D.

2002-01-01

A longitudinal evaluation measured the effects of neurolinguistic programming (NLP) on 67 hospitality worker immediately before and after and 6 weeks and 6 months after training. Positive increases in interpersonal communication appeared after 6 weeks, leveling off or declining after 6 months. Self-efficacy, self-esteem, and adaptive selling…

Revisiting the Occupational Aspirations and Destinations of Anglo-Australian and Chinese-Australian High School Students

ERIC Educational Resources Information Center

Malik, Ranbir Singh

2015-01-01

Evidence from Australia lends support to the "Asian high achieving syndrome" in Chinese-Australian students and "self-deprivation syndrome" in Anglo-Australian students. Applying ethnographic case studies approach for doctoral thesis the author collected data on a longitudinal basis from homes and school of these students. All…

Gaining Insight into Hispanic Students' Postsecondary Plans

ERIC Educational Resources Information Center

Brown, Neel A.

2012-01-01

While the growth of the Hispanic population in the United States is outpacing other ethnicities, college enrollment and graduation rates of Hispanic students continue to lag behind other groups. This longitudinal, qualitative case study explored when, how, and why a sample of Hispanic high school seniors at a large high school in North Central…

Hairline fractures following volar plating of the distal radius: a recently recognized hardware-related complication.

PubMed

Otremski, Hila; Dolkart, Oleg; Atlan, Franck; Hutt, Dan; Segev, Elad; Pritsch, Tamir; Rosenblatt, Yishai

2018-06-01

Intraoperative hairline longitudinal fractures were recently reported in association with distal radius volar plating. Our aim was to further analyze this newly described complication. A retrospective radiographic and chart review was performed on 225 patients who underwent distal radius plating between June 2013 and June 2015. The Acu-Loc/Acu-Loc2© plating system (Acumed, Hillsboro, OR, USA) was used in 208 cases, and the VariAx© plating system (Stryker, Kalamazoo, MI, USA) was used in 17 cases. Three independent reviewers performed a blind evaluation of all relevant radiographs for the occurrence of longitudinal fractures around the plate, and validity was considered only when there was agreement among all three of them. Hairline longitudinal fractures were identified in 57 cases (25%), 55 with the Acu-Loc/Acu-Loc2© system and 2 with the VariAx© system. All fractures occurred with volar plating. Fracture occurrence was associated with age over 59 years, female gender, extra-articular fractures, and the use of Hexalobe screws (Acu-Loc/Acu-Loc2© system). We believe that the source of fracture occurrence lies within the screw design and that better screw design and possibly tapping in patients at risk may reduce the occurrence of intraoperative hairline longitudinal fractures. Further clinical and biomechanical research is needed to better understand this newly reported complication.

Elevated incidence rates of diabetes in Peru: report from PERUDIAB, a national urban population-based longitudinal study

PubMed Central

Seclen, Segundo Nicolas; Rosas, Moises Ernesto; Arias, Arturo Jaime; Medina, Cecilia Alexandra

2017-01-01

Objective A recent report from a non-nationally representative, geographically diverse sample in four separate communities in Peru suggests an unusually high diabetes incidence. We aimed to estimate the national diabetes incidence rate using PERUDIAB, a probabilistic, national urban population-based longitudinal study. Research design and methods 662 subjects without diabetes, selected by multistage, cluster, random sampling of households, representing the 24 administrative and the 3 (coast, highlands and jungle) natural regions across the country, from both sexes, aged 25+ years at baseline, enrolled in 2010–2012, were followed for 3.8 years. New diabetes cases were defined as fasting blood glucose ≥126 mg/dL or on medical diabetes treatment. Results There were 49 cases of diabetes in 2408 person-years follow-up. The weighted cumulative incidence of diabetes was 7.2% while the weighted incidence rate was estimated at 19.5 (95% CI 13.9 to 28.3) new cases per 1000 person-years. Older age, obesity and technical or higher education were statistically associated with the incidence of diabetes. Conclusion Our results confirm that the incidence of diabetes in Peru is among the highest reported globally. The fast economic growth in the last 20 years, high overweight and obesity rates may have triggered this phenomenon. PMID:28878935

Elevated incidence rates of diabetes in Peru: report from PERUDIAB, a national urban population-based longitudinal study.

PubMed

Seclen, Segundo Nicolas; Rosas, Moises Ernesto; Arias, Arturo Jaime; Medina, Cecilia Alexandra

2017-01-01

A recent report from a non-nationally representative, geographically diverse sample in four separate communities in Peru suggests an unusually high diabetes incidence. We aimed to estimate the national diabetes incidence rate using PERUDIAB, a probabilistic, national urban population-based longitudinal study. 662 subjects without diabetes, selected by multistage, cluster, random sampling of households, representing the 24 administrative and the 3 (coast, highlands and jungle) natural regions across the country, from both sexes, aged 25+ years at baseline, enrolled in 2010-2012, were followed for 3.8 years. New diabetes cases were defined as fasting blood glucose ≥126 mg/dL or on medical diabetes treatment. There were 49 cases of diabetes in 2408 person-years follow-up. The weighted cumulative incidence of diabetes was 7.2% while the weighted incidence rate was estimated at 19.5 (95% CI 13.9 to 28.3) new cases per 1000 person-years. Older age, obesity and technical or higher education were statistically associated with the incidence of diabetes. Our results confirm that the incidence of diabetes in Peru is among the highest reported globally. The fast economic growth in the last 20 years, high overweight and obesity rates may have triggered this phenomenon.

Incident Subjective Cognitive Decline Does Not Predict Mortality in the Elderly--Results from the Longitudinal German Study on Ageing, Cognition, and Dementia (AgeCoDe).

PubMed

Roehr, Susanne; Luck, Tobias; Heser, Kathrin; Fuchs, Angela; Ernst, Annette; Wiese, Birgitt; Werle, Jochen; Bickel, Horst; Brettschneider, Christian; Koppara, Alexander; Pentzek, Michael; Lange, Carolin; Prokein, Jana; Weyerer, Siegfried; Mösch, Edelgard; König, Hans-Helmut; Maier, Wolfgang; Scherer, Martin; Jessen, Frank; Riedel-Heller, Steffi G

2016-01-01

Subjective cognitive decline (SCD) might represent the first symptomatic representation of Alzheimer's disease (AD), which is associated with increased mortality. Only few studies, however, have analyzed the association of SCD and mortality, and if so, based on prevalent cases. Thus, we investigated incident SCD in memory and mortality. Data were derived from the German AgeCoDe study, a prospective longitudinal study on the epidemiology of mild cognitive impairment (MCI) and dementia in primary care patients over 75 years covering an observation period of 7.5 years. We used univariate and multivariate Cox regression analyses to examine the relationship of SCD and mortality. Further, we estimated survival times by the Kaplan Meier method and case-fatality rates with regard to SCD. Among 971 individuals without objective cognitive impairment, 233 (24.0%) incidentally expressed SCD at follow-up I. Incident SCD was not significantly associated with increased mortality in the univariate (HR = 1.0, 95% confidence interval = 0.8-1.3, p = .90) as well as in the multivariate analysis (HR = 0.9, 95% confidence interval = 0.7-1.2, p = .40). The same applied for SCD in relation to concerns. Mean survival time with SCD was 8.0 years (SD = 0.1) after onset. Incident SCD in memory in individuals with unimpaired cognitive performance does not predict mortality. The main reason might be that SCD does not ultimately lead into future cognitive decline in any case. However, as prevalence studies suggest, subjectively perceived decline in non-memory cognitive domains might be associated with increased mortality. Future studies may address mortality in such other cognitive domains of SCD in incident cases.

Vector tomography for reconstructing electric fields with non-zero divergence in bounded domains

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koulouri, Alexandra, E-mail: koulouri@uni-muenster.de; Department of Electrical and Electronic Engineering, Imperial College London, Exhibition Road, London SW7 2BT; Brookes, Mike

In vector tomography (VT), the aim is to reconstruct an unknown multi-dimensional vector field using line integral data. In the case of a 2-dimensional VT, two types of line integral data are usually required. These data correspond to integration of the parallel and perpendicular projection of the vector field along the integration lines and are called the longitudinal and transverse measurements, respectively. In most cases, however, the transverse measurements cannot be physically acquired. Therefore, the VT methods are typically used to reconstruct divergence-free (or source-free) velocity and flow fields that can be reconstructed solely from the longitudinal measurements. In thismore » paper, we show how vector fields with non-zero divergence in a bounded domain can also be reconstructed from the longitudinal measurements without the need of explicitly evaluating the transverse measurements. To the best of our knowledge, VT has not previously been used for this purpose. In particular, we study low-frequency, time-harmonic electric fields generated by dipole sources in convex bounded domains which arise, for example, in electroencephalography (EEG) source imaging. We explain in detail the theoretical background, the derivation of the electric field inverse problem and the numerical approximation of the line integrals. We show that fields with non-zero divergence can be reconstructed from the longitudinal measurements with the help of two sparsity constraints that are constructed from the transverse measurements and the vector Laplace operator. As a comparison to EEG source imaging, we note that VT does not require mathematical modeling of the sources. By numerical simulations, we show that the pattern of the electric field can be correctly estimated using VT and the location of the source activity can be determined accurately from the reconstructed magnitudes of the field. - Highlights: • Vector tomography is used to reconstruct electric fields generated by dipole sources. • Inverse solutions are based on longitudinal and transverse line integral measurements. • Transverse line integral measurements are used as a sparsity constraint. • Numerical procedure to approximate the line integrals is described in detail. • Patterns of the studied electric fields are correctly estimated.« less

Longitudinal relationship between traumatic brain injury and the risk of incident optic neuropathy: A 10-year follow-up nationally representative Taiwan survey

PubMed Central

Chen, Ying-Jen; Liang, Chang-Min; Tai, Ming-Cheng; Chang, Yun-Hsiang; Lin, Tzu-Yu; Chung, Chi-Hsiang; Lin, Fu-Huang; Tsao, Chang-Huei; Chien, Wu-Chien

2017-01-01

Accumulating evidences had shown that traumatic brain injury was associated with visual impairment or vision loss. However, there were a limited number of empirical studies regarding the longitudinal relationship between traumatic brain injury and incident optic neuropathy. We studied a cohort from the Taiwanese National Health Insurance data comprising 553918 participants with traumatic brain injury and optic neuropathy-free in the case group and 1107836 individuals without traumatic brain injury in the control group from 1st January 2000. After the index date until the end of 2010, Cox proportional hazards analysis was used to compare the risk of incident optic neuropathy. During the follow-up period, case group was more likely to develop incident optic neuropathy (0.24%) than the control group (0.11%). Multivariate Cox regression analysis demonstrated that the case group had a 3-fold increased risk of optic neuropathy (HR = 3.017, 95% CI = 2.767–3.289, p < 0.001). After stratification by demographic information, traumatic brain injury remained a significant factor for incident optic neuropathy. Our study provided evidence of the increased risk of incident optic neuropathy after traumatic brain injury during a 10-year follow-up period. Patients with traumatic brain injury required periodic and thorough eye examinations for incident optic neuropathy to prevent potentially irreversible vision loss. PMID:29156847

Longitudinal relationship between traumatic brain injury and the risk of incident optic neuropathy: A 10-year follow-up nationally representative Taiwan survey.

PubMed

Chen, Ying-Jen; Liang, Chang-Min; Tai, Ming-Cheng; Chang, Yun-Hsiang; Lin, Tzu-Yu; Chung, Chi-Hsiang; Lin, Fu-Huang; Tsao, Chang-Huei; Chien, Wu-Chien

2017-10-17

Accumulating evidences had shown that traumatic brain injury was associated with visual impairment or vision loss. However, there were a limited number of empirical studies regarding the longitudinal relationship between traumatic brain injury and incident optic neuropathy. We studied a cohort from the Taiwanese National Health Insurance data comprising 553918 participants with traumatic brain injury and optic neuropathy-free in the case group and 1107836 individuals without traumatic brain injury in the control group from 1st January 2000. After the index date until the end of 2010, Cox proportional hazards analysis was used to compare the risk of incident optic neuropathy. During the follow-up period, case group was more likely to develop incident optic neuropathy (0.24%) than the control group (0.11%). Multivariate Cox regression analysis demonstrated that the case group had a 3-fold increased risk of optic neuropathy (HR = 3.017, 95% CI = 2.767-3.289, p < 0.001). After stratification by demographic information, traumatic brain injury remained a significant factor for incident optic neuropathy. Our study provided evidence of the increased risk of incident optic neuropathy after traumatic brain injury during a 10-year follow-up period. Patients with traumatic brain injury required periodic and thorough eye examinations for incident optic neuropathy to prevent potentially irreversible vision loss.

Antenatal Workup of Early Megacystis and Selection of Candidates for Fetal Therapy.

PubMed

Fontanella, Federica; Duin, Leonie; Adama van Scheltema, Phebe N; Cohen-Overbeek, Titia E; Pajkrt, Eva; Bekker, Mireille; Willekes, Christine; Bax, Caroline J; Oepkes, Dick; Bilardo, Catia M

2018-05-17

To investigate the best criteria for discriminating fetuses with isolated posterior urethral valves from those theoretically not eligible for fetal treatment because of complex megacystis, high chance of spontaneous resolution, and urethral atresia. A retrospective national study was conducted in fetuses with megacystis detected before 17 weeks' gestation (early megacystis). In total, 142 cases with fetal megacystis were included in the study: 52 with lower urinary tract obstruction, 29 with normal micturition at birth, and 61 with miscellaneous syndromal associations, chromosomal and multiple structural abnormalities (complex megacystis). Only a nuchal translucency > 95th centile, and not a longitudinal bladder diameter ≤15 mm (p = 0.24), significantly increased the risk of complex megacystis (p < 0.01). Cases with a high chance of spontaneous resolution were identified by using the cut-off of 12 mm, as demonstrated in a previous study, and the finding of an associated umbilical cord cyst carried a high-risk of urethral atresia (odds ratio: 15; p = 0.026), an unfavorable condition for antenatal treatment. An algorithm encompassing these three criteria demonstrated good accuracy in selecting fetuses theoretically eligible for fetal treatment (specificity 73%; sensitivity 92%). Cases theoretically eligible for early fetal therapy are those with normal nuchal translucency, a longitudinal bladder diameter > 12 mm, and without ultrasound evidence of umbilical cord cysts. © 2018 The Author(s) Published by S. Karger AG, Basel.

Continuity and Respect for Diversity: Strengthening Early Transitions in Peru. Working Papers in Early Childhood Development, No. 56. Studies in Early Childhood Transitions

ERIC Educational Resources Information Center

Ames, Patricia; Rojas, Vanessa; Portugal, Tamia

2010-01-01

This working paper is part of a series on early transitions from "Young Lives," a 15-year longitudinal study of childhood poverty in Ethiopia, India, Peru and Vietnam. It explores the diverse experiences of 28 children from four contrasting communities in Peru as they start school. These detailed case studies highlight common problems:…

[Autoaggression and pulse rate--a longitudinal study].

PubMed

Rohmann, U H; Elbing, U; Hartmann, H

1988-12-01

This article presents a model of autoaggressive behavior in which a distinction is made between determining and maintaining factors. Specific environmental, in particular social, and organismic variables are linked to them. The two types of variables interact, thus causing or maintaining autoaggressive behavior. A theory of autoaggression must therefore rely on multicausal/multimodal explanations. A connection between autoaggression and a high level of arousal suggests itself. In this single-case longitudinal study a comparison was made between heart rate and frequency of autoaggressive behavior. High heart rates were found to be correlated with low frequencies of autoaggressive behavior and vice versa. Decreasing autoaggressive behavior was coupled with increasing muscle relaxation and increasing motor activity. However, abnormally high heart rates were associated with both low and high levels of motor activity.

The Role of Social Capital at Home and in School in Academic Achievement: The Case of South Korea

ERIC Educational Resources Information Center

Yang, Hyunwoo

2017-01-01

Using data from the Korean Educational Longitudinal Study of 2005-2007, the current study investigated the role of family and school social capital in students' academic achievement in South Korea. Results showed that while some forms of family and school social capital were associated with increased math achievement, the effect of family social…

Where from, Who, Why and How? A Study of the Use of Sources by First Year L2 University Students

ERIC Educational Resources Information Center

Thompson, Celia; Morton, Janne; Storch, Neomy

2013-01-01

Knowing how to use sources effectively often poses considerable challenges for first year undergraduate students for whom English is a second language (L2). In this longitudinal case study we investigated the selection and self-reported use of source materials by thirteen first year L2 undergraduate students from a range of disciplines enrolled at…

The Case for Use of Simple Difference Scores to Test the Significance of Differences in Mean Rates of Change in Controlled Repeated Measurements Designs

ERIC Educational Resources Information Center

Overall, John E.; Tonidandel, Scott

2010-01-01

A previous Monte Carlo study examined the relative powers of several simple and more complex procedures for testing the significance of difference in mean rates of change in a controlled, longitudinal, treatment evaluation study. Results revealed that the relative powers depended on the correlation structure of the simulated repeated measurements.…

Family Implementation of Positive Behavior Support for a Child with Autism: Longitudinal, Single-Case, Experimental, and Descriptive Replication and Extension

ERIC Educational Resources Information Center

Lucyshyn, Joseph M.; Albin, Richard W.; Horner, Robert H.; Mann, Jane C.; Mann, James A.; Wadsworth, Gina

2007-01-01

This study examined the efficacy, social validity, and durability of a positive behavior support (PBS) approach with the family of a girl with autism and severe problem behavior. The study was conducted across a 10-year period beginning when the child was 5 years old. A multiple baseline across family routines design evaluated the functional…

The Green Bean Has to Be Longer than Your Thumb: An Observational Study of Preschoolers' Math and Science Experiences in a Garden

ERIC Educational Resources Information Center

Vandermaas-Peeler, Maureen; McClain, Cara

2015-01-01

School gardening has become increasingly popular as a context for learning in which children construct new knowledge, learn cultural and societal values related to ecological awareness, and develop and practice authentic or real-world skills (Blair, 2009; Bowker & Tearle, 2007). The present research was a longitudinal case study of children's…

Rural habitat as risk factor for hepatitis E virus seroconversion in HIV-infected patients: A prospective longitudinal study.

PubMed

Rivero-Juarez, A; Cuenca-Lopez, F; Martinez-Peinado, A; Camacho, A; Real, L M; Frias, M; Gordon, A; Cantisán, S; Torre-Cisneros, J; Pineda, J A; Rivero, A

2017-11-01

Our objective was to determine the incidence and clinical manifestations of acute hepatitis E virus (HEV) in HIV-infected patients. A prospective longitudinal study including HIV-infected HEV-seronegative patients was conducted; HEV seroconversion (to IgG and/or IgM) was the main outcome variable. All patients were tested for HEV antibodies every 3-6 months. For patients who developed HEV seroconversion, a data collection protocol was followed to identify associated clinical manifestations and analytical alterations. A total of 627 patients (89.9%) were followed during a median of 11.96 months (IQR: 8.52-14.52 months) and formed the study population. Forty-one patients developed detectable anti-HEV antibodies (7.2 cases per 100 patients/year). Our study found a high incidence of HEV in HIV-infected patients in southern Spain strongly associated with a rural habitat. © 2017 Blackwell Verlag GmbH.

The free and cued selective reminding test for predicting progression to Alzheimer's disease in patients with mild cognitive impairment: A prospective longitudinal study.

PubMed

Lemos, Raquel; Marôco, João; Simões, Mário R; Santiago, Beatriz; Tomás, José; Santana, Isabel

2017-03-01

Amnestic mild cognitive impairment (aMCI) patients carry a greater risk of conversion to Alzheimer's disease (AD). Therefore, the International Working Group (IWG) on AD aims to consider some cases of aMCI as symptomatic prodromal AD. The core diagnostic marker of AD is a significant and progressive memory deficit, and the Free and Cued Selective Reminding Test (FCSRT) was recommended by the IWG to test memory in cases of possible prodromal AD. This study aims to investigate whether the performance on the FCSRT would enhance the ability to predict conversion to AD in an aMCI group. A longitudinal study was conducted on 88 aMCI patients, and neuropsychological tests were analysed on the relative risk of conversion to AD. During follow-up (23.82 months), 33% of the aMCI population converted to AD. An impaired FCSRT TR was significantly associated with the risk of conversion to dementia, with a mean time to conversion of 25 months. The FCSRT demonstrates utility for detecting AD at its prodromal stage, thus supporting its use as a valid clinical marker. © 2015 The British Psychological Society.

Constitutional growth delay pattern of growth in velo-cardio-facial syndrome: longitudinal follow up and final height of two cases.

PubMed

Turan, Serap; Ozdemir, Nihal; Güran, Tülay; Akalın, Figen; Akçay, Teoman; Ayabakan, Canan; Yılmaz, Yüksel; Bereket, Abdullah

2008-01-01

We report two patients with velo-cardio-facial syndrome (VCFS) who were admitted to our pediatric endocrinology clinic because of short stature and followed longitudinally until attainment of final height. Both patients followed a growth pattern consistent with constitutional delay of puberty with normal and near normal final height. Case 2 also had partial growth hormone (GH) deficiency and severe short stature (height SDS -3.4 SDS), but showed spontaneous catch-up and ended up with a final height of -2 SDS. These cases suggest that short stature in children with VCFS is due to a pattern of growth similar to that observed in constitutional delay of growth and puberty.

Functional Logistic Regression Approach to Detecting Gene by Longitudinal Environmental Exposure Interaction in a Case-Control Study

PubMed Central

Wei, Peng; Tang, Hongwei; Li, Donghui

2014-01-01

Most complex human diseases are likely the consequence of the joint actions of genetic and environmental factors. Identification of gene-environment (GxE) interactions not only contributes to a better understanding of the disease mechanisms, but also improves disease risk prediction and targeted intervention. In contrast to the large number of genetic susceptibility loci discovered by genome-wide association studies, there have been very few successes in identifying GxE interactions which may be partly due to limited statistical power and inaccurately measured exposures. While existing statistical methods only consider interactions between genes and static environmental exposures, many environmental/lifestyle factors, such as air pollution and diet, change over time, and cannot be accurately captured at one measurement time point or by simply categorizing into static exposure categories. There is a dearth of statistical methods for detecting gene by time-varying environmental exposure interactions. Here we propose a powerful functional logistic regression (FLR) approach to model the time-varying effect of longitudinal environmental exposure and its interaction with genetic factors on disease risk. Capitalizing on the powerful functional data analysis framework, our proposed FLR model is capable of accommodating longitudinal exposures measured at irregular time points and contaminated by measurement errors, commonly encountered in observational studies. We use extensive simulations to show that the proposed method can control the Type I error and is more powerful than alternative ad hoc methods. We demonstrate the utility of this new method using data from a case-control study of pancreatic cancer to identify the windows of vulnerability of lifetime body mass index on the risk of pancreatic cancer as well as genes which may modify this association. PMID:25219575

Functional logistic regression approach to detecting gene by longitudinal environmental exposure interaction in a case-control study.

PubMed

Wei, Peng; Tang, Hongwei; Li, Donghui

2014-11-01

Most complex human diseases are likely the consequence of the joint actions of genetic and environmental factors. Identification of gene-environment (G × E) interactions not only contributes to a better understanding of the disease mechanisms, but also improves disease risk prediction and targeted intervention. In contrast to the large number of genetic susceptibility loci discovered by genome-wide association studies, there have been very few successes in identifying G × E interactions, which may be partly due to limited statistical power and inaccurately measured exposures. Although existing statistical methods only consider interactions between genes and static environmental exposures, many environmental/lifestyle factors, such as air pollution and diet, change over time, and cannot be accurately captured at one measurement time point or by simply categorizing into static exposure categories. There is a dearth of statistical methods for detecting gene by time-varying environmental exposure interactions. Here, we propose a powerful functional logistic regression (FLR) approach to model the time-varying effect of longitudinal environmental exposure and its interaction with genetic factors on disease risk. Capitalizing on the powerful functional data analysis framework, our proposed FLR model is capable of accommodating longitudinal exposures measured at irregular time points and contaminated by measurement errors, commonly encountered in observational studies. We use extensive simulations to show that the proposed method can control the Type I error and is more powerful than alternative ad hoc methods. We demonstrate the utility of this new method using data from a case-control study of pancreatic cancer to identify the windows of vulnerability of lifetime body mass index on the risk of pancreatic cancer as well as genes that may modify this association. © 2014 Wiley Periodicals, Inc.

A retrospective longitudinal study of animal and human rabies in Botswana 1989-2006.

PubMed

Moagabo, K T; Monyame, K B; Baipoledi, E K; Letshwenyo, M; Mapitse, N; Hyera, J M K

2009-12-01

A longitudinal study of animal and human rabies covering 18 years from 1989 to 2006 was retrospectively conducted in order to highlight the epidemiological features and trends of the disease in Botswana. Over the 18-year period, a total of 4 306 brain specimens collected from various species of animals including human beings with clinical signs consistent with rabies were submitted to the National Veterinary Laboratory in Gaborone for confirmatory diagnosis. Of the samples submitted, 2419 cases were found to be positive for lyssavirus antigen; this presents an overall prevalence rate of 56.18 +/- 1.48%. About 85.7% (2 074/2 419) of the cases were from domestic animals, 14.2% (343/2 419) cases were from wild animals and two cases (0.1%) were from human beings. During the first half of the study (1989-1997) the prevalence rate of the disease was estimated at 62.79 +/- 1.85% (1645/2620 positive) whereas during the second half (1998-2006) it was estimated at 45.91 +/- 2.38% (774/1686 positive) and the difference between the two estimates was statistically, highly significant (delta % = 16.88, SE(95) diff % = 3.015, SD = 5.599; P < 0.001). Ruminant rabies accounted for 79.99% (50.92% bovine, 928.40% caprine and 0.67% ovine) whereas canine (domestic dog) and feline (domestic cat) accounted for 16.01 and 0.87%, respectively. Equine rabies accounted for 3.13% with 1.35 and 1.78%, respectively, for horses and donkeys. Jackal rabies accounted for more than 60% of the total cases in wild animals. These findings are discussed in relation to the previous epidemiological situation of the disease (1979-1988), its socio-economic impact, monitoring and control in Botswana.

Longitudinal safety evaluation of electric vehicles with the partial wireless charging lane on freeways.

PubMed

Li, Ye; Wang, Wei; Xing, Lu; Fan, Qi; Wang, Hao

2018-02-01

As an environment friendly transportation mode, the electric vehicle (EV) has drawn an increasing amount of attention from governments, vehicle manufactories and researchers recently. One of the biggest issue impeding EV's popularization associates with the charging process. The wireless charging lane (WCL) has been proposed as a convenient charging facility for EVs. Due to the high costs, the application of WCL on the entire freeways is impractical in the near future, while the partial WCL (PWCL) may be a feasible solution. This study aims to evaluate longitudinal safety of EVs with PWCL on freeways based on simulations. The simulation experiments are firstly designed, including deployment of PWCL on freeways and distribution of state of charge (SOC) of EVs. Then, a vehicle behavior model for EVs is proposed based on the intelligent driver model (IDM). Two surrogate safety measures, derived from time-to-collision (TTC), are utilized as indicators for safety evaluations. Sensitivity analysis is also conducted for related factors. Results show that the distribution of EVs' SOC significantly affect longitudinal safety when the PWCL is utilized. The low SOC in traffic consisting of EVs has the negative effect on longitudinal safety. The randomness and incompliance of EV drivers worsens the safety performance. The sensitivity analysis indicates that the larger maximum deceleration rate results in the higher longitudinal crash risks of EVs, while the length of PWCL has no monotonous effect. Different TTC thresholds also show no impact on results. A case study shows the consistent results. Based on the findings, several suggestions are discussed for EVs' safety improvement. Results of this study provide useful information for freeway safety when EVs are applied in the future. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bayesian quantile regression-based partially linear mixed-effects joint models for longitudinal data with multiple features.

PubMed

Zhang, Hanze; Huang, Yangxin; Wang, Wei; Chen, Henian; Langland-Orban, Barbara

2017-01-01

In longitudinal AIDS studies, it is of interest to investigate the relationship between HIV viral load and CD4 cell counts, as well as the complicated time effect. Most of common models to analyze such complex longitudinal data are based on mean-regression, which fails to provide efficient estimates due to outliers and/or heavy tails. Quantile regression-based partially linear mixed-effects models, a special case of semiparametric models enjoying benefits of both parametric and nonparametric models, have the flexibility to monitor the viral dynamics nonparametrically and detect the varying CD4 effects parametrically at different quantiles of viral load. Meanwhile, it is critical to consider various data features of repeated measurements, including left-censoring due to a limit of detection, covariate measurement error, and asymmetric distribution. In this research, we first establish a Bayesian joint models that accounts for all these data features simultaneously in the framework of quantile regression-based partially linear mixed-effects models. The proposed models are applied to analyze the Multicenter AIDS Cohort Study (MACS) data. Simulation studies are also conducted to assess the performance of the proposed methods under different scenarios.

Vitamin D levels and risk for periodontal disease: A systematic review.

PubMed

Pinto, J P N S; Goergen, J; Muniz, F W M G; Haas, A N

2018-06-01

To evaluate the existing evidence supporting or refuting the following questions: (i) Do patients with lower vitamin D levels have higher risk for periodontal disease? (ii) Are periodontal treatment outcomes improved by the adjuvant supplementation of vitamin D or by elevated serum vitamin D levels? MEDLINE, SCOPUS, EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched up to September 2017. Studies were included if they had measured serum vitamin D levels or vitamin D intake and any periodontal parameter. Overall, 27 studies were included (13 cross-sectional studies, 6 case-control studies, 5 cohort studies, 2 randomized clinical trials and 1 case series study). Sixty-five percent of the cross-sectional studies reported significant associations between low vitamin D levels and poor periodontal parameters. None of the observational longitudinal studies found that periodontal disease progression could be attributed to lower vitamin D levels. No interventional studies that evaluated the use of vitamin D supplementation as a solely adjuvant to periodontal treatment was found. No meta-analysis was performed due to high variability across studies. The data to support or refute the association between vitamin D levels and periodontal disease are inconclusive at the moment. More rigorously designed longitudinal studies with standardized definitions of periodontal disease and vitamin D are necessary. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Wound and surface temperatures in vivo in torsional and longitudinal modalities of ultrasound in coaxial microincisional cataract surgery

PubMed Central

Nair, Swapna; Nair, Ramachandran Unnikrishnan

2017-01-01

Background To study phacoemulsification probe shaft/wound and corneal surface/tip temperatures in vivo during longitudinal, torsional and combined phacoemulsification modes and their relationship to machine parameters. Design This was a prospective study at Chaithanya Eye Hospital and Research Institute, Trivandrum, India (tertiary). Participants Twenty-two eyes of 22 patients were randomized into six groups depending on the grade of nuclear sclerosis (NS) and the type of ultrasound used: Group 1, torsional in NS2; Group 2, torsional in NS3; Group 3, torsional with intermittent longitudinal in NS2; Group 4, torsional with intermittent longitudinal in NS3; Group 5, longitudinal in NS2; Group 6, longitudinal in NS3. Methods Patients underwent phacoemulsification by torsional, longitudinal or combined modalities. A thermal camera was used to measure phaco probe temperatures. Main outcome measures The mean probe shaft and tip temperatures were documented for different ultrasound modalities. Results The mean shaft and tip temperatures were: Group 1, 29.22°C±0.71°C and 28.4°C±0.88°C; Group 2, 32.12°C±0.62°C and 31.88°C±0.84°C; Group 3, 30.25°C±0.71°C and 29.35°C±0.62°C; Group 4, 31.95°C±0.65°C and 32.01°C±1.31°C; Group 5, 23°C and 27.6°C and Group 6, 23°C and 29.68°C, respectively. In all groups using longitudinal ultrasound, the phaco tip surface temperatures were higher than the shaft temperatures, except in Group 3. Shaft temperatures were higher than tip temperatures in cases using torsional phaco, except in Group 4. The mean temperature difference between groups was significant only for shaft temperatures (P=0.001). On thermal imaging, for torsional phaco, the rise in temperature of the probe from shaft to tip was dependent on the amplitude of ultrasound applied (P=0.009). Conclusion The shaft temperatures were higher than over the phaco tip during torsional phacoemulsification. PMID:28184151

Early detection of myocardial dysfunction using two-dimensional speckle tracking echocardiography in a young cat with hypertrophic cardiomyopathy

PubMed Central

Mochizuki, Yohei; Yoshimatsu, Hiroki; Niina, Ayaka; Teshima, Takahiro; Matsumoto, Hirotaka; Koyama, Hidekazu

2018-01-01

Case summary A 5-month-old intact female Scottish Fold cat was presented for cardiac evaluation. Careful auscultation detected a slight systolic murmur (Levine I/VI). The findings of electrocardiography, thoracic radiography, non-invasive blood pressure measurements and conventional echocardiographic studies were unremarkable. However, two-dimensional speckle tracking echocardiography revealed abnormalities in myocardial deformations, including decreased early-to-late diastolic strain rate ratios in longitudinal, radial and circumferential directions, and deteriorated segmental systolic longitudinal strain. At the follow-up examinations, the cat exhibited echocardiographic left ventricular hypertrophy and was diagnosed with hypertrophic cardiomyopathy using conventional echocardiography. Relevance and novel information This is the first report on the use of two-dimensional speckle tracking echocardiography for the early detection of myocardial dysfunction in a cat with hypertrophic cardiomyopathy; the myocardial dysfunction was detected before the development of hypertrophy. The findings from this case suggest that two-dimensional speckle tracking echocardiography can be useful for myocardial assessment when conventional echocardiographic and Doppler findings are ambiguous. PMID:29449957

High-resolution three-dimensional 19F-magnetic resonance imaging of rat lung in situ: evaluation of airway strain in the perfluorocarbon-filled lung.

PubMed

Weigel, Julia K; Steinmann, Daniel; Emerich, Philipp; Stahl, Claudius A; v Elverfeldt, Dominik; Guttmann, Josef

2011-02-01

Perfluorocarbons (PFC) are biologically and chemically inert fluids with high oxygen and CO(2) carrying capacities. Their use as liquid intrapulmonary gas carriers during liquid ventilation has been investigated. We established a method of high resolution 3D-(19)F-MRI of the totally PFC-filled lung. The goal of this study was to investigate longitudinal and circumferential airway strain in the setting of increasing airway pressures on 3D-(19)F-MR images of the PFC-filled lung. Sixteen female Wistar rats were euthanized and the liquid perfluorocarbon FC-84 instilled into their lungs. 3D-(19)F-MRI was performed at various intrapulmonary pressures. Measurements of bronchial length and cross-sectional area were obtained from transversal 2D images for each pressure range. Changes in bronchial area were used to determine circumferential strain, while longitudinal strain was calculated from changes in bronchial length. Our method of 3D-(19)F-MRI allowed clear visualization of the great bronchi. Longitudinal strain increased significantly up to 31.1 cmH(2)O. The greatest strain could be found in the range of low airway pressures. Circumferential strain increased strongly with the initial pressure rise, but showed no significant changes above 10.4 cmH(2)O. Longitudinal strain was generally higher in distal airways, while circumferential strain showed no difference. Analysis of mechanical characteristics showed that longitudinal and circumferential airway expansion occurred in an anisotropic fashion. Whereas longitudinal strain still increased with higher pressures, circumferential strain quickly reached a 'strain limit'. Longitudinal strain was higher in distal bronchi, as dense PFCs gravitate to dependent, in this case to dorso-basal parts of the lung, acting as liquid positive end expiratory pressure.

Caring to Care: Applying Noddings' Philosophy to Medical Education.

PubMed

Balmer, Dorene F; Hirsh, David A; Monie, Daphne; Weil, Henry; Richards, Boyd F

2016-12-01

The authors argue that Nel Noddings' philosophy, "an ethic of caring," may illuminate how students learn to be caring physicians from their experience of being in a caring, reciprocal relationship with teaching faculty. In her philosophy, Noddings acknowledges two important contextual continuities: duration and space, which the authors speculate exist within longitudinal integrated clerkships. In this Perspective, the authors highlight core features of Noddings' philosophy and explore its applicability to medical education. They apply Noddings' philosophy to a subset of data from a previously published longitudinal case study to explore its "goodness of fit" with the experience of eight students in the 2012 cohort of the Columbia-Bassett longitudinal integrated clerkship. In line with Noddings' philosophy, the authors' supplementary analysis suggests that students (1) recognized caring when they talked about "being known" by teaching faculty who "cared for" and "trusted" them; (2) responded to caring by demonstrating enthusiasm, action, and responsibility toward patients; and (3) acknowledged that duration and space facilitated caring relations with teaching faculty. The authors discuss how Noddings' philosophy provides a useful conceptual framework to apply to medical education design and to future research on caring-oriented clinical training, such as longitudinal integrated clerkships.

Genetic erosion in maize's center of origin.

PubMed

Dyer, George A; López-Feldman, Alejandro; Yúnez-Naude, Antonio; Taylor, J Edward

2014-09-30

Crop genetic diversity is an indispensable resource for farmers and professional breeders responding to changing climate, pests, and diseases. Anecdotal appraisals in centers of crop origin have suggested serious threats to this diversity for over half a century. However, a nationwide inventory recently found all maize races previously described for Mexico, including some formerly considered nearly extinct. A flurry of social studies seems to confirm that farmers maintain considerable diversity. Here, we compare estimates of maize diversity from case studies over the past 15 y with nationally and regionally representative matched longitudinal data from farmers across rural Mexico. Our findings reveal an increasing bias in inferences based on case study results and widespread loss of diversity. Cross-sectional, case study data suggest that farm-level richness has increased by 0.04 y(-1) nationwide; however, direct estimates using matched longitudinal data reveal that richness dropped -0.04 y(-1) between 2002 and 2007, from 1.43 to 1.22 varieties per farm. Varietal losses occurred across regions and altitudinal zones, and regardless of farm turnover within the sector. Extinction of local maize populations may not have resulted in an immediate loss of alleles, but low varietal richness and changes in maize's metapopulation dynamics may prevent farmers from accessing germplasm suitable to a rapidly changing climate. Declining yields could then lead farmers to leave the sector and result in a further loss of diversity. Similarities in research approaches across crops suggest that methodological biases could conceal a loss of diversity at other centers of crop origin.

Relationship satisfaction in women: a longitudinal case-control study about the role of breast cancer, personal assertiveness, and partners' relationship-focused coping.

PubMed

Hinnen, Chris; Hagedoorn, Mariët; Ranchor, Adelita V; Sanderman, Robbert

2008-11-01

The aim of this study was to investigate whether a breast cancer diagnosis, personal assertiveness (i.e. frequency of assertive behaviour and tension associated with this behaviour), and partners' relationship-focused coping (i.e. active engagement and protective buffering) were sources of variation in patients' relationship satisfaction, cross-sectionally and over time. This longitudinal case-control study assessed the two dimensions of personal assertiveness and relationship satisfaction in both women with cancer (N=72) and comparison controls (N=62). In addition, patients completed a measure assessing their partners' active engagement and protective buffering. Cases (i.e. women with breast cancer) were not found to report more relationship problems than controls. Women with breast cancer who tended not to express their concerns and feelings and who experienced much tension when they did, reported relatively low marital satisfaction. Moreover, partners' protective buffering was associated with less relationship satisfaction in especially more assertive (i.e. high frequency of assertive behaviour and low tension) women with cancer, while active engagement was associated with more relationship satisfaction, regardless of the women's personal assertiveness. The results of the present study indicate that a breast cancer diagnosis by itself may not be a risk factor for relationship problems. However, in the context of an illness such as cancer, personal assertiveness, and a partner's relationship-focused coping strategies do seem to play a role in maintaining a satisfactory relationship with one's partner.

Spectropolarimetry of magnetic stars. IV. The crossover effect.

NASA Astrophysics Data System (ADS)

Mathys, G.

1995-01-01

This paper is devoted to the study of the crossover effect in magnetic Ap stars. It is shown that this effect can be measured by the second order moment about their centre of the profiles of spectral lines recorded in the Stokes parameter V. The interpretation of these measurements in terms of magnetic field is developed. It is shown that one can derive from them a quantity called the mean asymmetry of the longitudinal magnetic field, which is the first moment of the component of the magnetic field along the line of sight, about the plane defined by the line of sight and the stellar rotation axis. The consistency of the determination of this quantity with that of the mean longitudinal magnetic field from measurements of wavelength shifts of lines between right and left circular polarization is demonstrated. This technique of analysis is applied to observations of a sample of 29 stars, among which 10 have a detectable crossover effect. For 8 of them, the available observational data allow the study of the variations of the asymmetry of the longitudinal field with rotation phase. In most cases, this variation is sinusoidal and essentially symmetric about 0, and it occurs in quadrature with the variation of the mean longitudinal field. A more complex behaviour is definitely observed in HD 147010 and HD 175362, where the variation of the asymmetry of the longitudinal field is better represented by the superposition of two sinusoids, one with the rotation frequency of the star, and the other with twice that frequency.

An Algorithm for Creating Virtual Controls Using Integrated and Harmonized Longitudinal Data.

PubMed

Hansen, William B; Chen, Shyh-Huei; Saldana, Santiago; Ip, Edward H

2018-06-01

We introduce a strategy for creating virtual control groups-cases generated through computer algorithms that, when aggregated, may serve as experimental comparators where live controls are difficult to recruit, such as when programs are widely disseminated and randomization is not feasible. We integrated and harmonized data from eight archived longitudinal adolescent-focused data sets spanning the decades from 1980 to 2010. Collectively, these studies examined numerous psychosocial variables and assessed past 30-day alcohol, cigarette, and marijuana use. Additional treatment and control group data from two archived randomized control trials were used to test the virtual control algorithm. Both randomized controlled trials (RCTs) assessed intentions, normative beliefs, and values as well as past 30-day alcohol, cigarette, and marijuana use. We developed an algorithm that used percentile scores from the integrated data set to create age- and gender-specific latent psychosocial scores. The algorithm matched treatment case observed psychosocial scores at pretest to create a virtual control case that figuratively "matured" based on age-related changes, holding the virtual case's percentile constant. Virtual controls matched treatment case occurrence, eliminating differential attrition as a threat to validity. Virtual case substance use was estimated from the virtual case's latent psychosocial score using logistic regression coefficients derived from analyzing the treatment group. Averaging across virtual cases created group estimates of prevalence. Two criteria were established to evaluate the adequacy of virtual control cases: (1) virtual control group pretest drug prevalence rates should match those of the treatment group and (2) virtual control group patterns of drug prevalence over time should match live controls. The algorithm successfully matched pretest prevalence for both RCTs. Increases in prevalence were observed, although there were discrepancies between live and virtual control outcomes. This study provides an initial framework for creating virtual controls using a step-by-step procedure that can now be revised and validated using other prevention trial data.

Longitudinal multiple imputation approaches for body mass index or other variables with very low individual-level variability: the mibmi command in Stata.

PubMed

Kontopantelis, Evangelos; Parisi, Rosa; Springate, David A; Reeves, David

2017-01-13

In modern health care systems, the computerization of all aspects of clinical care has led to the development of large data repositories. For example, in the UK, large primary care databases hold millions of electronic medical records, with detailed information on diagnoses, treatments, outcomes and consultations. Careful analyses of these observational datasets of routinely collected data can complement evidence from clinical trials or even answer research questions that cannot been addressed in an experimental setting. However, 'missingness' is a common problem for routinely collected data, especially for biological parameters over time. Absence of complete data for the whole of a individual's study period is a potential bias risk and standard complete-case approaches may lead to biased estimates. However, the structure of the data values makes standard cross-sectional multiple-imputation approaches unsuitable. In this paper we propose and evaluate mibmi, a new command for cleaning and imputing longitudinal body mass index data. The regression-based data cleaning aspects of the algorithm can be useful when researchers analyze messy longitudinal data. Although the multiple imputation algorithm is computationally expensive, it performed similarly or even better to existing alternatives, when interpolating observations. The mibmi algorithm can be a useful tool for analyzing longitudinal body mass index data, or other longitudinal data with very low individual-level variability.

"It's Different Lives": A Guatemalan American Adolescent's Construction of Ethnic and Gender Identities across Educational Contexts

ERIC Educational Resources Information Center

Ek, Lucila D.

2009-01-01

Drawing from a multiyear ethnography and a longitudinal case study, this article examines how one Guatemalan American teenager negotiates the multiple socializations to ethnic and gender identities in her home, her Pentecostal church, and her high school. She must face processes of Americanization and Mexicanization. Americanization's thrust is to…

Gendered Transitions, Career Identities and Possible Selves: The Case of Engineering Graduates

ERIC Educational Resources Information Center

Papafilippou, Vanda; Bentley, Laura

2017-01-01

This article, drawing upon the Paired Peers project, a longitudinal qualitative study (n = 90), examines how seven UK engineering graduates, four women and three men, construct their career identities during the transitionary period from university to work. It explores how gender and the occupational cultures that reside within the sector, and the…

Professional Development and the Teaching Schools Experiment in England: Leadership Challenges in an Alliance's First Year

ERIC Educational Resources Information Center

Dowling, Simon

2016-01-01

This article reports findings from the first year of a longitudinal, mixed-methods case study of a large teaching school alliance in England. This national initiative is intended to drive improvement at system level by grouping schools around formally designated teaching schools. These "alliances" work collaboratively to share learning,…

Dancing Sexual Pleasures: Exploring Teenage Women's Experiences of Sexuality and Pleasure beyond "Sex"

ERIC Educational Resources Information Center

Austin, Josie I.

2016-01-01

This paper focuses on the affective and sensual dimensions of sexuality, especially on what feels good in and on the body. Drawing on a longitudinal participatory case study of a young Christian woman's dancing practices, it illustrates how for young women sexual feelings and sexual pleasure are not only pertinent to those practices normatively…

My Voice Heard: The Journey of a Young Man with a Cerebral Visual Impairment

ERIC Educational Resources Information Center

Macintyre-Beon, Catriona; Mitchell, Kate; Gallagher, Ian; Cockburn, Debbie; Dutton, Gordon N.; Bowman, Richard

2012-01-01

This longitudinal case study presents John's journey through childhood and adolescence, living with visual difficulties associated with a cerebral visual impairment. It highlights the day-to-day problems that John encountered, giving practical solutions and strategies that have enabled his dream of going to a university to be realized. John and…

Collaborative Research Projects in the Technology-Enhanced Language Classroom: Preservice and In-Service Teachers Exchange Knowledge about Technology

ERIC Educational Resources Information Center

Schmid, Euline Cutrim; Hegelheimer, Volker

2014-01-01

This paper presents research findings of a longitudinal empirical case study that investigated an innovative Computer Assisted Language Learning (CALL) professional development program for pre-service English as Foreign Language (EFL) teachers. The conceptualization of the program was based on the assumption that pre-service language teachers…

Peer Production for Collaboration between Academics and Practitioners

ERIC Educational Resources Information Center

Ponti, Marisa

2013-01-01

The purpose of this article is to suggest commons-based peer production as a form of work that can help bridge the gap between research and practice in LIS. The research design is based on two in-depth and longitudinal qualitative case studies of collaborative projects involving LIS academics and practitioners in Italy. Analysis of interviews and…

Educating with Prezi: A New Presentation Paradigm for Teaching, Learning, and Leading in the Digital Age

ERIC Educational Resources Information Center

Safar, Ammar H.

2015-01-01

This longitudinal descriptive qualitative evaluation action research case study explored the reflections/experiences (i.e., their perceptions, attitudes, and feelings) of 450 pre-service teachers in the College of Education (COE) at Kuwait University (KU) over three academic years regarding the use of Prezi as a facilitative storytelling…

Language and Literacy Acquisition through Parental Mediation in American Sign Language

ERIC Educational Resources Information Center

Bailes, Cynthia Neese; Erting, Lynne C.; Thumann-Prezioso, Carlene; Erting, Carol J.

2009-01-01

This longitudinal case study examined the language and literacy acquisition of a Deaf child as mediated by her signing Deaf parents during her first three years of life. Results indicate that the parents' interactions with their child were guided by linguistic and cultural knowledge that produced an intuitive use of child-directed signing (CDSi)…

Students' Experiences of Mathematics during the Transition from Primary to Secondary School

ERIC Educational Resources Information Center

Attard, Catherine

2010-01-01

As part of a longitudinal case study on engagement in middle years mathematics, 20 students attending their first year of secondary school in Western Sydney were asked to provide views on their experiences of the transition to secondary school in relation to mathematics teaching and learning. Differences in teacher-student relationships caused the…

Early Childhood Education: The Sustainability of the Benefits of Preschool Participation in Abbott Districts

ERIC Educational Resources Information Center

Fernandez, Norma

2010-01-01

The landmark New Jersey Supreme Court school funding case, "Abbott v. Burke", established the availability of preschool for all three- and four-year-olds living within the state's thirty-one poorest districts as a means of eradicating the effects of poverty. Longitudinal studies have shown the value of high quality preschool programs for…

Understanding the Co-construction of Inquiry Practices: A Case Study of a Responsive Teaching Environment

ERIC Educational Resources Information Center

Maskiewicz, April C.; Winters, Victoria A.

2012-01-01

We set out to understand how different instantiations of inquiry emerged in two different years of one elementary teacher's classroom. Longitudinal observations from Mrs. Charles' 5th grade science classroom forced us to carefully and deliberately consider who exactly was responsible for the change in the class activities and norms. We provide…

Using Enactivism as a Methodology to Characterise Algebraic Learning

ERIC Educational Resources Information Center

Lozano, Maria-Dolores

2015-01-01

My purpose in this paper is to illustrate the way in which an enactivist methodological approach guided me as I conducted a two-case longitudinal study where the learning of algebra was explored in different contexts throughout time. Three groups of students in two different schools in the city of Puebla, Mexico, were followed from the last year…

Chicago Experience with an Early Childhood Programme: The Special Case of the Child Parent Center Program.

ERIC Educational Resources Information Center

Fuerst, J. S.; Fuerst, Dorothy

1993-01-01

Longitudinal study of Chicago's Child Parent Centers showed that four to six years' participation made a significant difference in black girls' achievement, but little difference for black boys; seven to nine years' training produced some changes for boys; and one- to two-year exposure showed no significant improvements. (SK)

Pragmatic Development as a Dynamic, Complex Process: General Patterns and Case Histories

ERIC Educational Resources Information Center

Taguchi, Naoko

2011-01-01

This longitudinal study asks 2 questions. The first one is: What patterns of pragmatic development can we observe among different pragmatic functions and attributes in a second language (L2)? The second question is: In what ways do individual differences and learning context affect the course of pragmatic development? Forty-eight Japanese college…

School Board Governance in Changing Times: A School's Transition to Policy Governance

ERIC Educational Resources Information Center

Curry, Katherine; Kinder, Sean; Benoiton, Tania; Noonan, Jessica

2018-01-01

The expansion of the school choice movement and greater flexibility allowed by Every Student Succeeds Act (ESSA) means that education governance is emerging as an important issue for school effectiveness. This longitudinal case study sought to gain an understanding of the implementation of a new governance structure, Policy Governance, in a…

Importance of Speech Production for Phonological Awareness and Word Decoding: The Case of Children with Cerebral Palsy

ERIC Educational Resources Information Center

Peeters, Marieke; Verhoeven, Ludo; de Moor, Jan; van Balkom, Hans

2009-01-01

The goal of this longitudinal study was to investigate the precursors of early reading development in 52 children with cerebral palsy at kindergarten level in comparison to 65 children without disabilities. Word Decoding was measured to investigate early reading skills, while Phonological Awareness, Phonological Short-term Memory (STM), Speech…

Moving beyond the Reflectivity of Post-Lesson Mentoring Conferences in Teacher Education and Creating Learning/development Opportunities for Pre-Service Teachers

ERIC Educational Resources Information Center

Ciavaldini-Cartaut, Solange

2015-01-01

This longitudinal case study suggests ways to move beyond the reflective process usually associated with post-lesson mentoring conferences by describing the modalities likely to generate real learning/development opportunities. Based on cultural-historical activity theories (CHAT) and using methodologies from sociodiscursive interactionism, this…

Looking Out and Looking In: Exploring a Case of Faculty Perceptions during E-Learning Staff Development

ERIC Educational Resources Information Center

Esterhuizen, Hendrik Daniel; Blignaut, Seugnet; Ellis, Suria

2013-01-01

This explorative study captured the perceptions of faculty members new to technology enhanced learning and the longitudinal observations of the e-learning manager during dedicated professional development in order to compile a socially transformative emergent learning technology integration framework for open and distance learning at the School of…

Supporting the Work Arrangements of Cooperating Teachers and University Supervisors to Better Train Preservice Teachers: A New Theoretical Contribution

ERIC Educational Resources Information Center

Escalié, Guillaume; Chaliès, Sébastien

2016-01-01

This longitudinal case study examines whether a school-based training scheme that brings together different categories of teacher educators (university supervisors and cooperating teachers) engenders true collective training activity and, if so, whether this collective work contributes to pre-service teacher education. The scheme grew out of a…

Art Making as a Mental Health Recovery Tool for Change and Coping

ERIC Educational Resources Information Center

Van Lith, Theresa

2015-01-01

The intrinsic benefits of art making may be implicated in how and why people with mental illness turn to art therapy to aid their recovery. In this longitudinal multiple case study adult participants (N = 12) with severe and ongoing mental illness were recruited through their involvement in diverse community mental health art therapy programs. An…

An Update on the "Cycle of Violence." Research in Brief.

ERIC Educational Resources Information Center

Widom, Cathy S.; Maxfield, Michael G.

This brief updates a longitudinal study comparing the arrest records of abused and neglected children with arrest records of non-abused or neglected children. Subjects included 908 substantiated cases of childhood abuse or neglect processed by the courts from 1967-71 who were matched by sex, age, race, and family socioeconomic status with 667…

Sequential Bimodal Bilingual Acquisition: Mediation Using a Cochlear Implant as a Tool

ERIC Educational Resources Information Center

Cramér-Wolrath, Emelie

2013-01-01

Most deaf children are born to hearing families. During the last twenty years deaf children, in increasing numbers and at an early age, receive a cochlear implant, a highly technological hearing device. The aim of this qualitative, longitudinal, single-case study was to explore and describe critical changes in naturalistic, video-observed…

The Development of Complexity, Accuracy and Fluency in the Written Production of L2 French

ERIC Educational Resources Information Center

Gunnarsson, Cecilia

2012-01-01

The present longitudinal case study investigated the development of fluency, complexity and accuracy--and the possible relationships between them--in the written production of L2 French. We assessed fluency and complexity in five intermediate learners by means of conventional indicators for written L2 (cf. Wolfe-Quintero et al. 1998), while…

The Case for Summer Bridge: Building Social and Cultural Capital for Talented Black STEM Students

ERIC Educational Resources Information Center

Stolle-McAllister, Kathleen

2011-01-01

This study uses focus groups to examine the importance of a pre-college summer bridge program for highly talented black students in science, technology, engineering, and mathematics (STEM). Longitudinal data were collected from 134 participants who identified three aspects of Summer Bridge that were particularly helpful: academic, social, and…

Is What's Hot in Reading What Should Be Important for Reading Instruction?

ERIC Educational Resources Information Center

Rasinski, Timothy

2016-01-01

For years one of the most anticipated events in reading instruction has been Jack Cassidy and his colleagues' annual publication of the "What's Hot, What's Not" survey. In their present study, using longitudinal data from the What's Hot survey, Cassidy, Ortlieb, and Grote-Garcia (2016) make the case that because the Common Core Standards…

Traumatic longitudinal splitting of the inferior rectus muscle

PubMed Central

Laursen, Jessica; Demer, Joseph L.

2011-01-01

Orbital floor fractures and associated injuries can cause strabismus. We present the case of a 34-year-old man with incomitant strabismus following orbital reconstruction after a high-impact baseball injury. Multipositional, high-resolution magnetic resonance imaging (MRI) revealed extensive longitudinal splitting of the inferior rectus muscle by an orbital floor implant that separated its orbital and global layers. PMID:21463958

A Proposed Approach for Joint Modeling of the Longitudinal and Time-To-Event Data in Heterogeneous Populations: An Application to HIV/AIDS's Disease.

PubMed

Roustaei, Narges; Ayatollahi, Seyyed Mohammad Taghi; Zare, Najaf

2018-01-01

In recent years, the joint models have been widely used for modeling the longitudinal and time-to-event data simultaneously. In this study, we proposed an approach (PA) to study the longitudinal and survival outcomes simultaneously in heterogeneous populations. PA relaxes the assumption of conditional independence (CI). We also compared PA with joint latent class model (JLCM) and separate approach (SA) for various sample sizes (150, 300, and 600) and different association parameters (0, 0.2, and 0.5). The average bias of parameters estimation (AB-PE), average SE of parameters estimation (ASE-PE), and coverage probability of the 95% confidence interval (CP) among the three approaches were compared. In most cases, when the sample sizes increased, AB-PE and ASE-PE decreased for the three approaches, and CP got closer to the nominal level of 0.95. When there was a considerable association, PA in comparison with SA and JLCM performed better in the sense that PA had the smallest AB-PE and ASE-PE for the longitudinal submodel among the three approaches for the small and moderate sample sizes. Moreover, JLCM was desirable for the none-association and the large sample size. Finally, the evaluated approaches were applied on a real HIV/AIDS dataset for validation, and the results were compared.

The longitudinal BMI pattern and body composition of patients with anorexia nervosa who require urgent hospitalization: A case control study.

PubMed

Kawai, Keisuke; Yamashita, Sakino; Yamanaka, Takeharu; Gondo, Motoharu; Morita, Chihiro; Nozaki, Takehiro; Takakura, Shu; Hata, Tomokazu; Yamada, Yu; Matsubayashi, Sunao; Takii, Masato; Kubo, Chiharu; Sudo, Nobuyuki

2011-12-05

The prevention of serious physical complications in anorexia nervosa (AN) patients is important. The purpose of this study is to clarify which physical and social factors are related to the necessity for urgent hospitalization of anorexia nervosa (AN) patients in a long-term starvation state. We hypothesized that the change of longitudinal BMI, body composition and social background would be useful as an index of the necessity for urgent hospitalization. AN patients were classified into; urgent hospitalization, due to disturbance of consciousness or difficulty walking(n = 17); planned admission (n = 96); and outpatient treatment only groups (n = 136). The longitudinal BMI pattern and the clinical features of these groups were examined. In the hospitalization groups, comparison was done of body composition variation and the social background, including the educational level and advice from family members. After adjusting for age and duration of illness, the BMI of the urgent hospitalization group was lower than that of the other groups at one year before hospitalization (P < 0.01) and decreased more rapidly (P < 0.01). Urgent hospitalization was associated with the fat free mass (FFM) (P < 0.01). Between the groups, no considerable difference in social factors was found. The longitudinal pattern of BMI and FFM may be useful for understanding the severity in AN from the viewpoint of failure of the homeostasis system.

Outcomes of Left Ventricular Function According to Treatment Response for a Patent Ductus Arteriosus in Preterm Infants.

PubMed

Kang, Soo Jung; Cho, Young Sun; Hwang, Seo Jung; Kim, Hyo Jin

2017-12-01

To evaluate the outcomes of left ventricular (LV) function according to treatment response for a hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. Echocardiograms of 21 preterm infants born at gestational age < 31 weeks obtained at term-equivalent age were retrospectively studied. Among preterm infants with a hsPDA, 9 underwent ligation after failure of pharmacological closure (ligation group) and 6 experienced successful pharmacological closure (medication group). Six preterm infants without hsPDA (no-hsPDA group) were studied as controls. LV peak longitudinal systolic strain (ε) of each infant was retrospectively obtained from echocardiograms using velocity vector imaging, along with neonatal outcomes. Pharmacological closures were attempted at postnatal day 2-3. In the ligation group, the median postnatal age at ligation was 20 days. In the ligation group, LV peak longitudinal systolic ε was significantly decreased at term-equivalent age compared to the other groups. Between the medication and no-hsPDA groups, LV peak longitudinal systolic ε did not differ significantly. Among the neonatal outcomes, infants who experienced necrotizing enterocolitis (NEC) showed significantly decreased LV peak longitudinal systolic ε compared to the infants who did not experience NEC . We speculate that in preterm infants with an hsPDA, in cases of medical treatment failure, early PDA ligation at less than 20 days of postnatal age would be beneficial for preserving LV systolic function.

Importance of cervical length in dysmenorrhoea aetiology.

PubMed

Zebitay, Ali G; Verit, Fatma F; Sakar, M Nafi; Keskin, Seda; Cetin, Orkun; Ulusoy, A Ibrahim

2016-05-01

The objective of this prospective case-control study was to determine whether uterine corpus and cervical length measurements have a role in dysmenorrhoea aetiology in virgins. Patients with severe primary dysmenorrhoea with visual analog scale scores of ≥7 composed the dysmenorrhoea group (n = 51), while the control group (n = 51) was of women with painless menstrual cycles or with mild pain. Longitudinal and transverse axes of the uterine cervix and uterine corpus were measured. Correlation between severity of dysmenorrhoea and uterine cervix and corpus axes was calculated. Longitudinal and transverse axes of uterine cervix as well as uterine cervix volume were significantly higher in the dysmenorrhoea group compared to the controls. There was a significant positive correlation between severity of dysmenorrhoea and the length of cervical longitudinal and transverse axes and uterine cervical volume. Our findings reveal longer cervical length and greater cervical volume in young virgin patients with dysmenorrhoea and severe pain compared to those with no or less pain.

Clinical and MRI correlates of disease progression in a case of nonfluent/agrammatic variant of primary progressive aphasia due to progranulin (GRN) Cys157LysfsX97 mutation.

PubMed

Caso, Francesca; Agosta, Federica; Magnani, Giuseppe; Galantucci, Sebastiano; Spinelli, Edoardo G; Galimberti, Daniela; Falini, Andrea; Comi, Giancarlo; Filippi, Massimo

2014-07-15

Little is known about the longitudinal changes of brain damage in patients with sporadic nonfluent/agrammatic variant of primary progressive aphasia (nfvPPA) and in progranulin (GRN) mutation carriers. This study reports the clinical and MRI longitudinal data of a patient with nfvPPA carrying GRN Cys157LysfsX97 mutation (GRN+). Voxel-based morphometry, tensor-based morphometry and diffusion tensor MRI were applied to evaluate gray matter (GM) and white matter (WM) changes over three years. The prominent clinical feature was motor speech impairment associated with only mild agrammatism. MRI demonstrated a progressive and severe GM atrophy of inferior fronto-insular-temporo-parietal regions with focal damage to frontotemporal and frontoparietal WM connections. This is the first report of longitudinal MRI data in a nfvPPA- GRN+ patient and this report offers new insights into the pathophysiology of the disease. Copyright © 2014 Elsevier B.V. All rights reserved.

Multivariate test power approximations for balanced linear mixed models in studies with missing data.

PubMed

Ringham, Brandy M; Kreidler, Sarah M; Muller, Keith E; Glueck, Deborah H

2016-07-30

Multilevel and longitudinal studies are frequently subject to missing data. For example, biomarker studies for oral cancer may involve multiple assays for each participant. Assays may fail, resulting in missing data values that can be assumed to be missing completely at random. Catellier and Muller proposed a data analytic technique to account for data missing at random in multilevel and longitudinal studies. They suggested modifying the degrees of freedom for both the Hotelling-Lawley trace F statistic and its null case reference distribution. We propose parallel adjustments to approximate power for this multivariate test in studies with missing data. The power approximations use a modified non-central F statistic, which is a function of (i) the expected number of complete cases, (ii) the expected number of non-missing pairs of responses, or (iii) the trimmed sample size, which is the planned sample size reduced by the anticipated proportion of missing data. The accuracy of the method is assessed by comparing the theoretical results to the Monte Carlo simulated power for the Catellier and Muller multivariate test. Over all experimental conditions, the closest approximation to the empirical power of the Catellier and Muller multivariate test is obtained by adjusting power calculations with the expected number of complete cases. The utility of the method is demonstrated with a multivariate power analysis for a hypothetical oral cancer biomarkers study. We describe how to implement the method using standard, commercially available software products and give example code. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Data Use and Inquiry in Research-Practice Partnerships: Four Case Examples

ERIC Educational Resources Information Center

Biag, Manuelito; Gerstein, Amy; Fehrer, Kendra; Sanchez, Monika; Sipes, Laurel

2016-01-01

The four case examples presented in this brief are drawn from the Gardner Center's substantial experience conducting rigorous research in research-practice partnerships. The first case describes a partnership approach that enhances a school district's capacity to use integrated longitudinal data to tackle persistent problems of practice and…

Design Aspects of a Case-Control Clinical Investigation of the Effect of HIV on Oral and Gastrointestinal Soluble Innate Factors and Microbes

PubMed Central

Phelan, Joan A.; Abrams, William R.; Norman, Robert G.; Li, Yihong; Laverty, Maura; Corby, Patricia M.; Nembhard, Jason; Neri, Dinah; Barber, Cheryl A.; Aberg, Judith A.; Fisch, Gene S.; Poles, Michael A.; Malamud, Daniel

2014-01-01

Introduction The impaired host defense system in HIV infection impacts the oral and gastrointestinal microbiota and associated opportunistic infections. Antiretroviral treatment is predicted to partially restore host defenses and decrease the oral manifestation of HIV/AIDS. Well-designed longitudinal studies are needed to better understand the interactions of soluble host defense proteins with bacteria and virus in HIV/AIDS. “Crosstalk” was designed as a longitudinal study of host responses along the gastrointestinal (GI) tract and interactions between defense molecules and bacteria in HIV infection and subsequent therapy. Purpose The clinical core formed the infrastructure for the study of the interactions between the proteome, microbiome and innate immune system. The core recruited and retained study subjects, scheduled visits, obtained demographic and medical data, assessed oral health status, collected samples, and guided analysis of the hypotheses. This manuscript presents a well-designed clinical core that may serve as a model for studies that combine clinical and laboratory data. Methods Crosstalk was a case-control longitudinal clinical study an initial planned enrollment of 170 subjects. HIV+ antiretroviral naïve subjects were followed for 9 visits over 96 weeks and HIV uninfected subjects for 3 visits over 24 weeks. Clinical prevalence of oral mucosal lesions, dental caries and periodontal disease were assessed. Results During the study, 116 subjects (47 HIV+, 69 HIV-) were enrolled. Cohorts of HIV+ and HIV- were demographically similar except for a larger proportion of women in the HIV- group. The most prevalent oral mucosal lesions were oral candidiasis and hairy leukoplakia in the HIV+ group. Discussion The clinical core was essential to enable the links between clinical and laboratory data. The study aims to determine specific differences between oral and GI tissues that account for unique patterns of opportunistic infections and to delineate the differences in their susceptibility to infection by HIV and their responses post-HAART. PMID:25409430

Design aspects of a case-control clinical investigation of the effect of HIV on oral and gastrointestinal soluble innate factors and microbes.

PubMed

Phelan, Joan A; Abrams, William R; Norman, Robert G; Li, Yihong; Laverty, Maura; Corby, Patricia M; Nembhard, Jason; Neri, Dinah; Barber, Cheryl A; Aberg, Judith A; Fisch, Gene S; Poles, Michael A; Malamud, Daniel

2014-01-01

The impaired host defense system in HIV infection impacts the oral and gastrointestinal microbiota and associated opportunistic infections. Antiretroviral treatment is predicted to partially restore host defenses and decrease the oral manifestation of HIV/AIDS. Well-designed longitudinal studies are needed to better understand the interactions of soluble host defense proteins with bacteria and virus in HIV/AIDS. "Crosstalk" was designed as a longitudinal study of host responses along the gastrointestinal (GI) tract and interactions between defense molecules and bacteria in HIV infection and subsequent therapy. The clinical core formed the infrastructure for the study of the interactions between the proteome, microbiome and innate immune system. The core recruited and retained study subjects, scheduled visits, obtained demographic and medical data, assessed oral health status, collected samples, and guided analysis of the hypotheses. This manuscript presents a well-designed clinical core that may serve as a model for studies that combine clinical and laboratory data. Crosstalk was a case-control longitudinal clinical study an initial planned enrollment of 170 subjects. HIV+ antiretroviral naïve subjects were followed for 9 visits over 96 weeks and HIV uninfected subjects for 3 visits over 24 weeks. Clinical prevalence of oral mucosal lesions, dental caries and periodontal disease were assessed. During the study, 116 subjects (47 HIV+, 69 HIV-) were enrolled. Cohorts of HIV+ and HIV- were demographically similar except for a larger proportion of women in the HIV- group. The most prevalent oral mucosal lesions were oral candidiasis and hairy leukoplakia in the HIV+ group. The clinical core was essential to enable the links between clinical and laboratory data. The study aims to determine specific differences between oral and GI tissues that account for unique patterns of opportunistic infections and to delineate the differences in their susceptibility to infection by HIV and their responses post-HAART.

Rotator cuff tear shape characterization: a comparison of two-dimensional imaging and three-dimensional magnetic resonance reconstructions.

PubMed

Gyftopoulos, Soterios; Beltran, Luis S; Gibbs, Kevin; Jazrawi, Laith; Berman, Phillip; Babb, James; Meislin, Robert

2016-01-01

The purpose of this study was to see if 3-dimensional (3D) magnetic resonance imaging (MRI) could improve our understanding of rotator cuff tendon tear shapes. We believed that 3D MRI would be more accurate than two-dimensional (2D) MRI for classifying tear shapes. We performed a retrospective review of MRI studies of patients with arthroscopically proven full-thickness rotator cuff tears. Two orthopedic surgeons reviewed the information for each case, including scope images, and characterized the shape of the cuff tear into crescent, longitudinal, U- or L-shaped longitudinal, and massive type. Two musculoskeletal radiologists reviewed the corresponding MRI studies independently and blind to the arthroscopic findings and characterized the shape on the basis of the tear's retraction and size using 2D MRI. The 3D reconstructions of each cuff tear were reviewed by each radiologist to characterize the shape. Statistical analysis included 95% confidence intervals and intraclass correlation coefficients. The study reviewed 34 patients. The accuracy for differentiating between crescent-shaped, longitudinal, and massive tears using measurements on 2D MRI was 70.6% for reader 1 and 67.6% for reader 2. The accuracy for tear shape characterization into crescent and longitudinal U- or L-shaped using 3D MRI was 97.1% for reader 1 and 82.4% for reader 2. When further characterizing the longitudinal tears as massive or not using 3D MRI, both readers had an accuracy of 76.9% (10 of 13). The overall accuracy of 3D MRI was 82.4% (56 of 68), significantly different (P = .021) from 2D MRI accuracy (64.7%). Our study has demonstrated that 3D MR reconstructions of the rotator cuff improve the accuracy of characterizing rotator cuff tear shapes compared with current 2D MRI-based techniques. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Desert plains classification based on Geomorphometrical parameters (Case study: Aghda, Yazd)

NASA Astrophysics Data System (ADS)

Tazeh, mahdi; Kalantari, Saeideh

2013-04-01

This research focuses on plains. There are several tremendous methods and classification which presented for plain classification. One of The natural resource based classification which is mostly using in Iran, classified plains into three types, Erosional Pediment, Denudation Pediment Aggradational Piedmont. The qualitative and quantitative factors to differentiate them from each other are also used appropriately. In this study effective Geomorphometrical parameters in differentiate landforms were applied for plain. Geomorphometrical parameters are calculable and can be extracted using mathematical equations and the corresponding relations on digital elevation model. Geomorphometrical parameters used in this study included Percent of Slope, Plan Curvature, Profile Curvature, Minimum Curvature, the Maximum Curvature, Cross sectional Curvature, Longitudinal Curvature and Gaussian Curvature. The results indicated that the most important affecting Geomorphometrical parameters for plain and desert classifications includes: Percent of Slope, Minimum Curvature, Profile Curvature, and Longitudinal Curvature. Key Words: Plain, Geomorphometry, Classification, Biophysical, Yazd Khezarabad.

Risk factors for common mental disorders in women. Population-based longitudinal study.

PubMed

Patel, Vikram; Kirkwood, Betty R; Pednekar, Sulochana; Weiss, Helen; Mabey, David

2006-12-01

The determinants of common mental disorders in women have not been described in longitudinal studies from a low-income country. Population-based cohort study of 2494 women aged 18 to 50 years, in India. The Revised Clinical Interview Schedule was used for the detection of common mental disorders. There were 39 incident cases of common mental disorder in 2166 participants eligible for analysis (12-month rate 1.8%, 95% CI 1.3-2.4%). The following baseline factors were independently associated with the risk for common mental disorder: poverty (low income and having difficulty making ends meet); being married as compared with being single; use of tobacco; experiencing abnormal vaginal discharge; reporting a chronic physical illness; and having higher psychological symptom scores at baseline. Programmes to reduce the burden of common mental disorder in women should target poorer women, women with chronic physical illness and who have gynaecological symptoms, and women who use tobacco.

Vector tomography for reconstructing electric fields with non-zero divergence in bounded domains

NASA Astrophysics Data System (ADS)

Koulouri, Alexandra; Brookes, Mike; Rimpiläinen, Ville

2017-01-01

In vector tomography (VT), the aim is to reconstruct an unknown multi-dimensional vector field using line integral data. In the case of a 2-dimensional VT, two types of line integral data are usually required. These data correspond to integration of the parallel and perpendicular projection of the vector field along the integration lines and are called the longitudinal and transverse measurements, respectively. In most cases, however, the transverse measurements cannot be physically acquired. Therefore, the VT methods are typically used to reconstruct divergence-free (or source-free) velocity and flow fields that can be reconstructed solely from the longitudinal measurements. In this paper, we show how vector fields with non-zero divergence in a bounded domain can also be reconstructed from the longitudinal measurements without the need of explicitly evaluating the transverse measurements. To the best of our knowledge, VT has not previously been used for this purpose. In particular, we study low-frequency, time-harmonic electric fields generated by dipole sources in convex bounded domains which arise, for example, in electroencephalography (EEG) source imaging. We explain in detail the theoretical background, the derivation of the electric field inverse problem and the numerical approximation of the line integrals. We show that fields with non-zero divergence can be reconstructed from the longitudinal measurements with the help of two sparsity constraints that are constructed from the transverse measurements and the vector Laplace operator. As a comparison to EEG source imaging, we note that VT does not require mathematical modeling of the sources. By numerical simulations, we show that the pattern of the electric field can be correctly estimated using VT and the location of the source activity can be determined accurately from the reconstructed magnitudes of the field.

Methods for Analyzing the Attainment of Graduate School Milestones: A Case Study. GRE Board Professional Report No. 86-3P.

ERIC Educational Resources Information Center

Zwick, Rebecca; Braun, Henry I.

Using a data base compiled by the Graduate School of Northwestern University, a longitudinal study of the graduate school careers of 2,211 students in 14 programs was conducted. Among the most prominent findings was the increase in the enrollment of foreign students. The patterns of attainment of graduate school milestones, such as Ph. D.…

"If I Had to Pick Any Subject, It Wouldn't Be Maths": Foundations for Engagement with Mathematics during the Middle Years

ERIC Educational Resources Information Center

Attard, Catherine

2013-01-01

This article is a report on a longitudinal case study that investigated the problem of lowered engagement with mathematics and students' perspectives of the factors that influenced their engagement during the middle years of schooling. The article provides a synthesis of the entire study and a summary of its findings. In order to address the…

Beliefs, Practical Knowledge, and Context: A Longitudinal Study of a Beginning Biology Teacher's 5E Unit

ERIC Educational Resources Information Center

Sickel, Aaron J.; Friedrichsen, Patricia

2015-01-01

The purpose of this three-year case study was to understand how a beginning biology teacher (Alice) designed and taught a 5E unit on natural selection, how the unit changed when she took a position in a different school district, and why the changes occurred. We examined Alice's developing beliefs about science teaching and learning,…

"But Before I Go to My Next Step": A Longitudinal Study of Adolescent English Language Learners' Transitional Devices in Oral Presentations

ERIC Educational Resources Information Center

Kibler, Amanda K.; Salerno, April S.; Palacios, Natalia

2014-01-01

This multiple case study examines patterns in the oral second language use of three Spanish-speaking English language learners in rehearsed presentations produced annually over 4 years (Grades 9-12) in a U.S. high school. Analysis focuses on students' changing use of transitional devices called frame markers (Hyland, 2005) as a lens for…

Understanding the Use of Graphic Novels to Support the Writing Skills of a Struggling Writer

ERIC Educational Resources Information Center

Voss, Christina L.

2013-01-01

This mixed methods study combining a single-subject experimental design with an embedded case study focuses on the impact of a visual treatment on the handwritten and typed output of a struggling male writer during his 5th through 7th grades who has undergone a longitudinal remedial phase of two and a half years creating text-only material as well…

From Education to Work: Cross-National Perspectives. Revisitations of Papers Delivered at the Conference at the University of Toronto (April 18-20, 1996).

ERIC Educational Resources Information Center

Heinz, Walter R., Ed.

This volume is composed of 13 comparable longitudinal studies that draw on survey data and case studies of young people in Canada, Germany, Great Britain, and the United States. "Introduction: Transitions to Employment in a Cross-National Perspective" (Walter R. Heinz) provides a context and an overview. Part I has four chapters that…

A Preliminary Assessment of the Change Recipients' Perceptions of the "4+4+4 Reform Initiative": Has Anything Changed?

ERIC Educational Resources Information Center

Summak, M. Semih

2016-01-01

The purpose of the present study was to assess change recipients' perceptions of 4+4+4 reform initiative put in effect in Turkish education system and to explore if anything has changed within the one-year interval. This research is a qualitative longitudinal case study conducted in 2013 and 2014 in a large city in Southeastern Turkey. Pragmatist…

A novel metadata management model to capture consent for record linkage in longitudinal research studies.

PubMed

McMahon, Christiana; Denaxas, Spiros

2017-11-06

Informed consent is an important feature of longitudinal research studies as it enables the linking of the baseline participant information with administrative data. The lack of standardized models to capture consent elements can lead to substantial challenges. A structured approach to capturing consent-related metadata can address these. a) Explore the state-of-the-art for recording consent; b) Identify key elements of consent required for record linkage; and c) Create and evaluate a novel metadata management model to capture consent-related metadata. The main methodological components of our work were: a) a systematic literature review and qualitative analysis of consent forms; b) the development and evaluation of a novel metadata model. We qualitatively analyzed 61 manuscripts and 30 consent forms. We extracted data elements related to obtaining consent for linkage. We created a novel metadata management model for consent and evaluated it by comparison with the existing standards and by iteratively applying it to case studies. The developed model can facilitate the standardized recording of consent for linkage in longitudinal research studies and enable the linkage of external participant data. Furthermore, it can provide a structured way of recording consent-related metadata and facilitate the harmonization and streamlining of processes.

Leadership in transformation: a longitudinal study in a nursing organization.

PubMed

Viitala, Riitta

2014-01-01

Not only does leadership produce changes, but those changes produce leadership in organisations. The purpose of this paper is to present a theoretical and empirical analysis of the transformation of leadership at two different historical points in a health care organisation. It leans on the perspective of social constructionism, drawing especially from the ideas of Berger and Luckmann (1966). The paper seeks to improve understanding of how leaders themselves construct leadership in relation to organisational change. The empirical material was gathered in a longitudinal case study in a nursing organisation in two different historical and situational points. It consists of written narratives produced by nurse leaders that are analysed by applying discourse analysis. The empirical study revealed that the constructions of leadership were dramatically different at the two different historical and situational points. Leadership showed up as a complex, fragile and changing phenomenon, which fluctuates along with the other organisational changes. The results signal the importance of agency in leadership and the central role of "significant others". The paper questions the traditional categorisation and labelling of leadership as well as the cross-sectional studies in understanding leadership transformation. Its originality relates to the longitudinal perspective on transformation of leadership in the context of a health care organisation.

DIZZINESS AND HEAD INJURY.

PubMed

BARBER, H O

1965-05-01

Dizziness, whether vague or specifically rotational, is a common sequel to head injury, and is often postural. One hundred and sixty-five patients with this symptom were examined. The simple posture tests employed to detect positional nystagmus are described. This physical finding was present in one-quarter of the entire group, and in nearly one-half of cases of longitudinal fracture of temporal bone. In such cases, it is an objective finding that corresponds precisely to the patient's complaint of vertigo.Transverse fracture of temporal bone destroys the inner ear in both cochlear and vestibular parts. Longitudinal fracture is commoner and causes bleeding from the ear; inner-ear damage is usually minor.In the rare cases where persisting postural vertigo and positional nystagmus are disabling, relief of the symptom may be achieved by vestibular denervation of the affected side.

Constitutional Growth Delay Pattern of Growth in Velo−Cardio−Facial Syndrome: Longitudinal follow up and final height of two cases

PubMed Central

Özdemir, Nihal; Güran, Tülay; Akalın, Figen; Akçay, Teoman; Ayabakan, Canan; Yılmaz, Yüksel; Bereket, Abdullah

2008-01-01

We report two patients with velo−cardio−facial syndrome (VCFS) who were admitted to our pediatric endocrinology clinic because of short stature and followed longitudinally until attainment of final height. Both patients followed a growth pattern consistent with constitutional delay of puberty with normal and near normal final height. Case 2 also had partial growth hormone (GH) deficiency and severe short stature (height SDS −3.4 SDS), but showed spontaneous catch−up and ended up with a final height of −2 SDS. These cases suggest that short stature in children with VCFS is due to a pattern of growth similar to that observed in constitutional delay of growth and puberty. Conflict of interest:None declared. PMID:21318064

Longitudinal control effectiveness and entry dynamics of a single-stage-to-orbit vehicle

NASA Technical Reports Server (NTRS)

Vinh, N. X.; Lin, C. F.

1982-01-01

The classical theory of flight dynamics for airplane longitudinal stability and control analysis was extended to the case of a hypervelocity reentry vehicle. This includes the elements inherent in supersonic and hypersonic flight such as the influence of the Mach number on aerodynamic characteristics, and the effect of the reaction control system and aerodynamic controls on the trim condition through a wide range of speed. Phugoid motion and angle of attack oscillation for typical cases of cruising flight, ballistic entry, and glide entry are investigated. In each case, closed form solutions for the variations in altitude, flight path angle, speed and angle of attack are obtained. The solutions explicitly display the influence of different regions design parameters and trajectory variables on the stability of the motion.

Experimental study of the laminar-turbulent transition of a concave wall in a parallel flow

NASA Technical Reports Server (NTRS)

Bippes, H.

1978-01-01

The instability of the laminar boundary layer flow along a concave wall was studied. Observations of these three-dimensional boundary layer phenomena were made using the hydrogen-bubble visualization technique. With the application of stereo-photogrammetric methods in the air-water system it was possible to investigate the flow processes qualitatively and quantitatively. In the case of a concave wall of sufficient curvature, a primary instability occurs first in the form of Goertler vortices with wave lengths depending upon the boundary layer thickness and the wall curvature. At the onset the amplification rate is in agreement with the linear theory. Later, during the non-linear amplification stage, periodic spanwise vorticity concentrations develop in the low velocity region between the longitudinal vortices. Then a meandering motion of the longitudinal vortex streets subsequently ensues, leading to turbulence.

Association of Genetic Risk for Schizophrenia With Nonparticipation Over Time in a Population-Based Cohort Study.

PubMed

Martin, Joanna; Tilling, Kate; Hubbard, Leon; Stergiakouli, Evie; Thapar, Anita; Davey Smith, George; O'Donovan, Michael C; Zammit, Stanley

2016-06-15

Progress has recently been made in understanding the genetic basis of schizophrenia and other psychiatric disorders. Longitudinal studies are complicated by participant dropout, which could be related to the presence of psychiatric problems and associated genetic risk. We tested whether common genetic variants implicated in schizophrenia were associated with study nonparticipation among 7,867 children and 7,850 mothers from the Avon Longitudinal Study of Parents and Children (ALSPAC; 1991-2007), a longitudinal population cohort study. Higher polygenic risk scores for schizophrenia were consistently associated with noncompletion of questionnaires by study mothers and children and nonattendance at data collection throughout childhood and adolescence (ages 1-15 years). These associations persisted after adjustment for other potential correlates of nonparticipation. Results suggest that persons at higher genetic risk for schizophrenia are likely to be underrepresented in cohort studies, which will underestimate risk of this and related psychiatric, cognitive, and behavioral phenotypes in the population. Statistical power to detect associations with these phenotypes will be reduced, while analyses of schizophrenia-related phenotypes as outcomes may be biased by the nonrandom missingness of these phenotypes, even if multiple imputation is used. Similarly, in complete-case analyses, collider bias may affect associations between genetic risk and other factors associated with missingness. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

Higher serum bilirubin level as a protective factor for the development of diabetes in healthy Korean men: a 4 year retrospective longitudinal study.

PubMed

Jung, Chang Hee; Lee, Min Jung; Kang, Yu Mi; Hwang, Jenie Yoonoo; Jang, Jung Eun; Leem, Jaechan; Park, Joong-Yeol; Kim, Hong-Kyu; Lee, Woo Je

2014-01-01

Bilirubin, a natural product of heme catabolism by heme oxygenase, one of key antioxidant enzymes, has been recognized as a substance with potent antioxidant and cytoprotective properties. Several studies have shown a significant negative relationship between serum bilirubin levels and the risk of metabolic disorders, including type 2 diabetes. However, longitudinal studies investigating the association of elevated serum bilirubin levels and type 2 diabetes are lacking. In the present study, we aimed to investigate the longitudinal effects of baseline serum bilirubin concentrations on the development of type 2 diabetes in healthy Korean men. This 4 year retrospective longitudinal observational study was conducted at the Asan Medical Center, Seoul, Republic of Korea. The study population consisted of 5960 men without type 2 diabetes who underwent routine health examinations in 2007 (baseline) and 2011 (follow-up). Baseline serum bilirubin concentrations were determined by the vanadate oxidation method. During a 4 year period, 409 incident cases of diabetes (6.9 %) were identified. Incident type 2 diabetes decreased across the baseline bilirubin quartile categories (P for trend <0.001). In multivariable-adjusted model, the relative risk (RR) for the development of type 2 diabetes was significantly lower in the highest (i.e., 1.30-2.00 mg/dl) than in the lowest bilirubin quartile category (i.e., ≤ 0.90 mg/dl), even after adjustment for confounding variables (RR=0.69, 95% confidence interval 0.48-0.99, P for trend = 0.041). The results indicate that serum total bilirubin level may provide additional information for predicting future development of type 2 diabetes in healthy subjects. © 2013.

The time course of neurolinguistic and neuropsychological symptoms in three cases of logopenic primary progressive aphasia.

PubMed

Etcheverry, Louise; Seidel, Barbara; Grande, Marion; Schulte, Stephanie; Pieperhoff, Peter; Südmeyer, Martin; Minnerop, Martina; Binkofski, Ferdinand; Huber, Walter; Grodzinsky, Yosef; Amunts, Katrin; Heim, Stefan

2012-06-01

Primary progressive aphasia (PPA) is a rare clinical dementia syndrome affecting predominantly language abilities. Word-finding difficulties and comprehension deficits despite relatively preserved cognitive functions are characteristic symptoms during the first two years, and distinguish PPA from other dementia types like Alzheimer's disease. However, the dynamics of changes in language and non-linguistic abilities are not well understood. Most studies on progression used cross-sectional designs, which provide only limited insight into the course of the disease. Here we report the results of a longitudinal study in three cases of logopenic PPA over a period of 18 months, with exemplary longitudinal data from one patient even over 46 months. A comprehensive battery of neurolinguistic and neuropsychological tests was applied four times at intervals of six months. Over this period, deterioration of verbal abilities such as picture naming, story retelling, and semantic word recall was found, and the individual decline was quantified and compared between the three patients. Furthermore, decrease in non-verbal skills such as divided attention and increasing apraxia was observed in all three patients. In addition, inter-subject variability in the progression with different focuses was observed, with one patient developing a non-fluent PPA variant. The longitudinal, multivariate investigation of logopenic PPA thus provides novel insights into the progressive deterioration of verbal as well as non-verbal abilities. These deficits may further interact and thus form a multi-causal basis for the patients' problems in every-day life which need to be considered when planning individually targeted intervention in PPA. Copyright © 2012 Elsevier Ltd. All rights reserved.

Brain mechanisms of recovery from pure alexia: A single case study with multiple longitudinal scans.

PubMed

Cohen, Laurent; Dehaene, Stanislas; McCormick, Samantha; Durant, Szonya; Zanker, Johannes M

2016-10-01

Pure alexia is an acquired reading disorder, typically due to a left occipito-temporal lesion affecting the Visual Word Form Area (VWFA). It is unclear whether the VWFA acts as a unique bottleneck for reading, or whether alternative routes are available for recovery. Here, we address this issue through the single-case longitudinal study of a neuroscientist who experienced pure alexia and participated in 17 behavioral, 9 anatomical, and 9 fMRI assessment sessions over a period of two years. The origin of the impairment was assigned to a small left fusiform lesion, accompanied by a loss of VWFA responsivity and by the degeneracy of the associated white matter pathways. fMRI experiments allowed us to image longitudinally the visual perception of words, as compared to other classes of stimuli, as well as the mechanisms of letter-by-letter reading. The progressive improvement of reading was not associated with the re-emergence of a new area selective to words, but with increasing responses in spared occipital cortex posterior to the lesion and in contralateral right occipital cortex. Those regions showed a non-specific increase of activations over time and an increase in functional correlation with distant language areas. Those results confirm the existence of an alternative occipital route for reading, bypassing the VWFA, but they also point to its key limitation: the patient remained a slow letter-by-letter reader, thus supporting the critical importance of the VWFA for the efficient parallel recognition of written words. Copyright © 2016 Elsevier Ltd. All rights reserved.

Longitudinal evaluation of corticospinal tract in patients with resected brainstem cavernous malformations using high-definition fiber tractography and diffusion connectometry analysis: preliminary experience.

PubMed

Faraji, Amir H; Abhinav, Kumar; Jarbo, Kevin; Yeh, Fang-Cheng; Shin, Samuel S; Pathak, Sudhir; Hirsch, Barry E; Schneider, Walter; Fernandez-Miranda, Juan C; Friedlander, Robert M

2015-11-01

Brainstem cavernous malformations (CMs) are challenging due to a higher symptomatic hemorrhage rate and potential morbidity associated with their resection. The authors aimed to preoperatively define the relationship of CMs to the perilesional corticospinal tracts (CSTs) by obtaining qualitative and quantitative data using high-definition fiber tractography. These data were examined postoperatively by using longitudinal scans and in relation to patients' symptomatology. The extent of involvement of the CST was further evaluated longitudinally using the automated "diffusion connectometry" analysis. Fiber tractography was performed with DSI Studio using a quantitative anisotropy (QA)-based generalized deterministic tracking algorithm. Qualitatively, CST was classified as being "disrupted" and/or "displaced." Quantitative analysis involved obtaining mean QA values for the CST and its perilesional and nonperilesional segments. The contralateral CST was used for comparison. Diffusion connectometry analysis included comparison of patients' data with a template from 90 normal subjects. Three patients (mean age 22 years) with symptomatic pontomesencephalic hemorrhagic CMs and varying degrees of hemiparesis were identified. The mean follow-up period was 37.3 months. Qualitatively, CST was partially disrupted and displaced in all. Direction of the displacement was different in each case and progressively improved corresponding with the patient's neurological status. No patient experienced neurological decline related to the resection. The perilesional mean QA percentage decreases supported tract disruption and decreased further over the follow-up period (Case 1, 26%-49%; Case 2, 35%-66%; and Case 3, 63%-78%). Diffusion connectometry demonstrated rostrocaudal involvement of the CST consistent with the quantitative data. Hemorrhagic brainstem CMs can disrupt and displace perilesional white matter tracts with the latter occurring in unpredictable directions. This requires the use of tractography to accurately define their orientation to optimize surgical entry point, minimize morbidity, and enhance neurological outcomes. Observed anisotropy decreases in the perilesional segments are consistent with neural injury following hemorrhagic insults. A model using these values in different CST segments can be used to longitudinally monitor its craniocaudal integrity. Diffusion connectometry is a complementary approach providing longitudinal information on the rostrocaudal involvement of the CST.

49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 4BW cylinder is a welded type steel cylinder with a longitudinal electric-arc welded seam, a water... a maximum wall stress of 24,000 p.s.i. in the formula described in paragraph (f)(4) of this section... any case the minimum wall thickness must be such that the wall stress calculated by the formula listed...

49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

Code of Federal Regulations, 2010 CFR

2010-10-01

... DOT 4BW cylinder is a welded type steel cylinder with a longitudinal electric-arc welded seam, a water... a maximum wall stress of 24,000 p.s.i. in the formula described in paragraph (f)(4) of this section... any case the minimum wall thickness must be such that the wall stress calculated by the formula listed...

The predictive value of post-traumatic stress disorder symptoms for quality of life: a longitudinal study of physically injured victims of non-domestic violence

PubMed Central

Johansen, Venke A; Wahl, Astrid K; Eilertsen, Dag Erik; Weisaeth, Lars; Hanestad, Berit R

2007-01-01

Background Little is known about longitudinal associations between post-traumatic stress disorder (PTSD) and quality of life (QoL) after exposure to violence. The aims of the current study were to examine quality of life (QoL) and the predictive value of post-traumatic stress disorder (PTSD) for QoL in victims of non-domestic violence over a period of 12 months. Methods A single-group (n = 70) longitudinal design with three repeated measures over a period of 12 months were used. Posttraumatic psychological symptoms were assessed by using the Impact of Event Scale, a 15-item self-rating questionnaire comprising two subscales (intrusion and avoidance) as a screening instrument for PTSD. The questionnaire WHOQOL-Bref was used to assess QoL. The WHOQOL-BREF instrument comprises 26 items, which measure the following broad domains: physical health, psychological health, social relationships, and environment. Results of the analysis were summarized by fitting Structural Equation Modelling (SEM). Results For each category of PTSD (probable cases, risk level cases and no cases), the mean levels of the WHOQOL-Bref subscales (the four domains and the two single items) were stable across time of assessment. Individuals who scored as probable PTSD or as risk level cases had significantly lower scores on the QoL domains such as physical health, psychological health, social relationships and environmental than those without PTSD symptoms. In addition, the two items examining perception of overall quality of life and perception of overall health in WHOQOL showed the same results according to PTSD symptoms such as QoL domains. PTSD symptoms predicted lower QoL at all three assessments. Similarly PTSD symptoms at T1 predicted lower QoL at T2 and PTSD symptoms at T2 predicted lower QoL at T3. Conclusion The presence of PTSD symptoms predicted lower QoL, both from an acute and prolonged perspective, in victims of non-domestic violence. Focusing on the individual's perception of his/her QoL in addition to the illness may increase the treatment priorities and efforts. PMID:17517126

The predictive value of post-traumatic stress disorder symptoms for quality of life: a longitudinal study of physically injured victims of non-domestic violence.

PubMed

Johansen, Venke A; Wahl, Astrid K; Eilertsen, Dag Erik; Weisaeth, Lars; Hanestad, Berit R

2007-05-21

Little is known about longitudinal associations between post-traumatic stress disorder (PTSD) and quality of life (QoL) after exposure to violence. The aims of the current study were to examine quality of life (QoL) and the predictive value of post-traumatic stress disorder (PTSD) for QoL in victims of non-domestic violence over a period of 12 months. A single-group (n = 70) longitudinal design with three repeated measures over a period of 12 months were used. Posttraumatic psychological symptoms were assessed by using the Impact of Event Scale, a 15-item self-rating questionnaire comprising two subscales (intrusion and avoidance) as a screening instrument for PTSD. The questionnaire WHOQOL-Bref was used to assess QoL. The WHOQOL-BREF instrument comprises 26 items, which measure the following broad domains: physical health, psychological health, social relationships, and environment. Results of the analysis were summarized by fitting Structural Equation Modelling (SEM). For each category of PTSD (probable cases, risk level cases and no cases), the mean levels of the WHOQOL-Bref subscales (the four domains and the two single items) were stable across time of assessment. Individuals who scored as probable PTSD or as risk level cases had significantly lower scores on the QoL domains such as physical health, psychological health, social relationships and environmental than those without PTSD symptoms. In addition, the two items examining perception of overall quality of life and perception of overall health in WHOQOL showed the same results according to PTSD symptoms such as QoL domains. PTSD symptoms predicted lower QoL at all three assessments. Similarly PTSD symptoms at T1 predicted lower QoL at T2 and PTSD symptoms at T2 predicted lower QoL at T3. The presence of PTSD symptoms predicted lower QoL, both from an acute and prolonged perspective, in victims of non-domestic violence. Focusing on the individual's perception of his/her QoL in addition to the illness may increase the treatment priorities and efforts.

Attrition Bias Related to Missing Outcome Data: A Longitudinal Simulation Study.

PubMed

Lewin, Antoine; Brondeel, Ruben; Benmarhnia, Tarik; Thomas, Frédérique; Chaix, Basile

2018-01-01

Most longitudinal studies do not address potential selection biases due to selective attrition. Using empirical data and simulating additional attrition, we investigated the effectiveness of common approaches to handle missing outcome data from attrition in the association between individual education level and change in body mass index (BMI). Using data from the two waves of the French RECORD Cohort Study (N = 7,172), we first examined how inverse probability weighting (IPW) and multiple imputation handled missing outcome data from attrition in the observed data (stage 1). Second, simulating additional missing data in BMI at follow-up under various missing-at-random scenarios, we quantified the impact of attrition and assessed how multiple imputation performed compared to complete case analysis and to a perfectly specified IPW model as a gold standard (stage 2). With the observed data in stage 1, we found an inverse association between individual education and change in BMI, with complete case analysis, as well as with IPW and multiple imputation. When we simulated additional attrition under a missing-at-random pattern (stage 2), the bias increased with the magnitude of selective attrition, and multiple imputation was useless to address it. Our simulations revealed that selective attrition in the outcome heavily biased the association of interest. The present article contributes to raising awareness that for missing outcome data, multiple imputation does not do better than complete case analysis. More effort is thus needed during the design phase to understand attrition mechanisms by collecting information on the reasons for dropout.

The impact of different strategies to handle missing data on both precision and bias in a drug safety study: a multidatabase multinational population-based cohort study

PubMed Central

Martín-Merino, Elisa; Calderón-Larrañaga, Amaia; Hawley, Samuel; Poblador-Plou, Beatriz; Llorente-García, Ana; Petersen, Irene; Prieto-Alhambra, Daniel

2018-01-01

Background Missing data are often an issue in electronic medical records (EMRs) research. However, there are many ways that people deal with missing data in drug safety studies. Aim To compare the risk estimates resulting from different strategies for the handling of missing data in the study of venous thromboembolism (VTE) risk associated with antiosteoporotic medications (AOM). Methods New users of AOM (alendronic acid, other bisphosphonates, strontium ranelate, selective estrogen receptor modulators, teriparatide, or denosumab) aged ≥50 years during 1998–2014 were identified in two Spanish (the Base de datos para la Investigación Farmacoepidemiológica en Atención Primaria [BIFAP] and EpiChron cohort) and one UK (Clinical Practice Research Datalink [CPRD]) EMR. Hazard ratios (HRs) according to AOM (with alendronic acid as reference) were calculated adjusting for VTE risk factors, body mass index (that was missing in 61% of patients included in the three databases), and smoking (that was missing in 23% of patients) in the year of AOM therapy initiation. HRs and standard errors obtained using cross-sectional multiple imputation (MI) (reference method) were compared to complete case (CC) analysis – using only patients with complete data – and longitudinal MI – adding to the cross-sectional MI model the body mass index/smoking values as recorded in the year before and after therapy initiation. Results Overall, 422/95,057 (0.4%), 19/12,688 (0.1%), and 2,051/161,202 (1.3%) VTE cases/participants were seen in BIFAP, EpiChron, and CPRD, respectively. HRs moved from 100.00% underestimation to 40.31% overestimation in CC compared with cross-sectional MI, while longitudinal MI methods provided similar risk estimates compared with cross-sectional MI. Precision for HR improved in cross-sectional MI versus CC by up to 160.28%, while longitudinal MI improved precision (compared with cross-sectional) only minimally (up to 0.80%). Conclusion CC may substantially affect relative risk estimation in EMR-based drug safety studies, since missing data are not often completely at random. Little improvement was seen in these data in terms of power with the inclusion of longitudinal MI compared with cross-sectional MI. The strategy for handling missing data in drug safety studies can have a large impact on both risk estimates and precision.

The impact of different strategies to handle missing data on both precision and bias in a drug safety study: a multidatabase multinational population-based cohort study.

PubMed

Martín-Merino, Elisa; Calderón-Larrañaga, Amaia; Hawley, Samuel; Poblador-Plou, Beatriz; Llorente-García, Ana; Petersen, Irene; Prieto-Alhambra, Daniel

2018-01-01

Missing data are often an issue in electronic medical records (EMRs) research. However, there are many ways that people deal with missing data in drug safety studies. To compare the risk estimates resulting from different strategies for the handling of missing data in the study of venous thromboembolism (VTE) risk associated with antiosteoporotic medications (AOM). New users of AOM (alendronic acid, other bisphosphonates, strontium ranelate, selective estrogen receptor modulators, teriparatide, or denosumab) aged ≥50 years during 1998-2014 were identified in two Spanish (the Base de datos para la Investigación Farmacoepidemiológica en Atención Primaria [BIFAP] and EpiChron cohort) and one UK (Clinical Practice Research Datalink [CPRD]) EMR. Hazard ratios (HRs) according to AOM (with alendronic acid as reference) were calculated adjusting for VTE risk factors, body mass index (that was missing in 61% of patients included in the three databases), and smoking (that was missing in 23% of patients) in the year of AOM therapy initiation. HRs and standard errors obtained using cross-sectional multiple imputation (MI) (reference method) were compared to complete case (CC) analysis - using only patients with complete data - and longitudinal MI - adding to the cross-sectional MI model the body mass index/smoking values as recorded in the year before and after therapy initiation. Overall, 422/95,057 (0.4%), 19/12,688 (0.1%), and 2,051/161,202 (1.3%) VTE cases/participants were seen in BIFAP, EpiChron, and CPRD, respectively. HRs moved from 100.00% underestimation to 40.31% overestimation in CC compared with cross-sectional MI, while longitudinal MI methods provided similar risk estimates compared with cross-sectional MI. Precision for HR improved in cross-sectional MI versus CC by up to 160.28%, while longitudinal MI improved precision (compared with cross-sectional) only minimally (up to 0.80%). CC may substantially affect relative risk estimation in EMR-based drug safety studies, since missing data are not often completely at random. Little improvement was seen in these data in terms of power with the inclusion of longitudinal MI compared with cross-sectional MI. The strategy for handling missing data in drug safety studies can have a large impact on both risk estimates and precision.

Effect of prospective reimbursement on nursing home costs.

PubMed Central

Coburn, A F; Fortinsky, R; McGuire, C; McDonald, T P

1993-01-01

OBJECTIVE. This study evaluates the effect of Maine's Medicaid nursing home prospective payment system on nursing home costs and access to care for public patients. DATA SOURCES/STUDY SETTING. The implementation of a facility-specific prospective payment system for nursing homes provided the opportunity for longitudinal study of the effect of that system. Data sources included audited Medicaid nursing home cost reports, quality-of-care data from state facility survey and licensure files, and facility case-mix information from random, stratified samples of homes and residents. Data were obtained for six years (1979-1985) covering the three-year period before and after implementation of the prospective payment system. STUDY DESIGN. This study used a pre-post, longitudinal analytical design in which interrupted, time-series regression models were estimated to test the effects of prospective payment and other factors, e.g., facility characteristics, nursing home market factors, facility case mix, and quality of care, on nursing home costs. PRINCIPAL FINDINGS. Prospective payment contributed to an estimated $3.03 decrease in total variable costs in the third year from what would have been expected under the previous retrospective cost-based payment system. Responsiveness to payment system efficiency incentives declined over the study period, however, indicating a growing problem in achieving further cost reductions. Some evidence suggested that cost reductions might have reduced access for public patients. CONCLUSIONS. Study findings are consistent with the results of other studies that have demonstrated the effectiveness of prospective payment systems in restraining nursing home costs. Potential policy trade-offs among cost containment, access, and quality assurance deserve further consideration, particularly by researchers and policymakers designing the new generation of case mix-based and other nursing home payment systems. PMID:8463109

Artistic Talent Development for Urban Youth: The Promise and the Challenge. Research Monograph Series.

ERIC Educational Resources Information Center

Oreck, Barry; Baum, Susan; McCartney, Heather

This longitudinal case study investigated issues that influence successful talent development in the arts and examined the effects of long-term artistic involvement on the lives of 23 artistically talented young people (ages 10-26) in New York City, all of whom had participated in a dance or music program in their elementary years. Most students…

Rurality and Resilience in Education: Place-Based Partnerships and Agency to Moderate Time and Space Constraints

ERIC Educational Resources Information Center

Ebersohn, Liesel; Ferreira, Ronel

2012-01-01

In an ongoing longitudinal intervention study (STAR) we found that, although similarities existed in the way teachers promoted resilience, rural schools (in comparison to other STAR case schools) took longer to implement strategies to buoy support and found it difficult to sustain such support. Using rurality we wanted to understand how forces,…

Predictors of Reading Comprehension for Struggling Readers: The Case of Spanish Speaking Language Minority Learners

ERIC Educational Resources Information Center

Mancilla-Martinez, Jeannette; Lesaux, Nonie K.

2010-01-01

This longitudinal study examined the process of English reading comprehension at age 11 years for 173 low-achieving Spanish-speaking children. The influence of growth rates, from early childhood (age 4.5 years) to pre-adolescence (age 11 years), in vocabulary and word reading skills on this complex process were evaluated with structural equation…

The Sustainability of Comprehensive School Reform Models in Changing District and State Contexts

ERIC Educational Resources Information Center

Datnow, Amanda

2005-01-01

This article addresses the sustainability of comprehensive school reform (CSR) models in the face of turbulent district and state contexts. It draws on qualitative data gathered in a longitudinal case study of six CSR models implemented in 13 schools in one urban district. Why do reforms sustain in some schools and not in others? How do changing…

Learner Agency in Language Learning: The Story of a Distance Learner of EFL in China

ERIC Educational Resources Information Center

Xiao, Junhong

2014-01-01

Learner agency plays a key role in self-regulated learning. Yet, there is a paucity of research into its role in the distance learning context. Using reflective narratives written by a distance learner of English in China, this longitudinal case study aims to investigate the ways in which learner agency mediates the language learning in the…

A Pedagogical Framework for the Use of Information and Communications Technology in Initial Teacher Training

ERIC Educational Resources Information Center

Hramiak, Alison

2006-01-01

This paper describes the initial findings of a longitudinal case study that investigates the use of e-learning and communications technology to enhance the placement experience for full-time post graduate certificate in education (PGCE) students. It is a work in progress examining how a VLE might be used to support trainees while they are on…

Experiential Learning and Values Education at a School Youth Camp: Maintaining Jewish Culture and Heritage

ERIC Educational Resources Information Center

Gross, Zehavit; Rutland, Suzanne D.

2017-01-01

In our post-modern, globalised world, there is a risk of unique cultural heritages being lost. This loss contributes to the detriment of civilization, because individuals need to be rooted in their own specific identity in order to actively participate in community life. This article discusses a longitudinal case study of the efforts being made by…

A Critical Account of Employability Construction through the Eyes of Chinese Postgraduate Students in the UK

ERIC Educational Resources Information Center

Li, Zhen

2013-01-01

This paper presents a multiple ("n"?=?23), longitudinal case study of the construction of personal employability by Chinese students at a UK university. It draws on the work of Brown and Hesketh to frame notions of employability in order to understand how these students engage with the international and Chinese labour markets from their…

Constructing Roma Students as Ethnic 'Others' through Orientalist Discourses in Bulgarian Schools

ERIC Educational Resources Information Center

Lambrev, Veselina; Traykov, Bozhin; Kirova, Anna

2018-01-01

This article uses the case of Bulgarian, predominantly Roma, schools to illustrate the long history of stereotypes about Roma people dating back to modernity's discursive binary oppositions of 'civilized' vs. 'barbarians.' The data from a longitudinal study with 12 Bulgarian educators showed the modes by which Roma as the Other is created in the…

Modeling the Impacts of National and Institutional Financial Aid Opportunities on Persistence at an Elite Chilean University

ERIC Educational Resources Information Center

Horn, Catherine; Santelices, María Verónica; Avendaño, Ximena Catalán

2014-01-01

Much of the recent Chilean educational debate and reform has centered around issues of higher education cost, debt burden, and availability of grants versus loans. This quantitative case study of Pontificia Universidad Católica de Chile sought to understand the longitudinal contributions of combinations of types of financial aid to persistence of…

Assisting with Qualification Completion by Applying the Concept of Occupational Identity as Conferred before Self-Inference: A Longitudinal Case Study of Bakery Apprentices

ERIC Educational Resources Information Center

Chan, Selena

2017-01-01

This paper proposes the utilisation of a method for matching qualifications' graduate profile outcomes to job roles and work responsibilities as apprenticeship progresses. In so doing, attainment of qualifications is made possible through the workplace validation of graduate profiles. Conferred occupational identity by other workers or managers…

Revealing organization of cellulose in wood cell walls by Raman imaging

Treesearch

Umesh P. Agarwal; Sally A. Ralph

2007-01-01

Anisotropy of cellulose organization in mature black spruce wood cell wall was investigated by Raman imaging using a 1 [mu]m lateral-resolution capable confocal Raman microscope. In these studies, wood cross sections (CS) and radial longitudinal sections (LS) that were partially delignified by acid chlorite treatment were used. In the case of CS where latewood cells...

Change Trajectories for the Youth Outcome Questionnaire Self-Report: Identifying Youth at Risk for Treatment Failure

ERIC Educational Resources Information Center

Cannon, Jennifer A. N.; Warren, Jared S.; Nelson, Philip L.; Burlingame, Gary M.

2010-01-01

This study used longitudinal youth outcome data in routine mental health services to test a system for identifying cases at risk for treatment failure. Participants were 2,715 youth (M age = 14) served in outpatient managed care and community mental health settings. Change trajectories were developed using multilevel modeling of archival data.…

Is the Court-Appointed Special Advocate Program Effective? A Longitudinal Analysis of Time Involvement and Case Outcomes.

ERIC Educational Resources Information Center

Leung, Patrick

1996-01-01

Describes the Court Appointed Special Advocate (CASA) Program for child welfare proceedings. Examines the current literature regarding the impact of CASA across the nation and discusses the findings and implications of an empirical study that evaluated a CASA program in terms of placement outcomes in a major U.S. city. (MOK)

Does a University Teacher Need to Change e-Learning Beliefs and Practices When Using a Social Networking Site? A Longitudinal Case Study

ERIC Educational Resources Information Center

Scott, Karen M.

2013-01-01

While much of the e-learning development at universities in the past 15 years has been on institutionally supported Learning Management Systems (LMSs), alternative educational technologies are being taken up following the rapid growth in emerging technologies, including social networking sites (SNSs). While teachers may choose educational…

The Anxiety-Proficiency Relationship and the Stability of Anxiety: The Case of Chinese University Learners of English and Japanese

ERIC Educational Resources Information Center

Jin, Yinxing; de Bot, Kees; Keijzer, Merel

2015-01-01

Adopting a longitudinal design, this study investigates the effects of foreign language anxiety on foreign language proficiency over time within English and Japanese learning contexts. It also explores the stability of anxiety in English and Japanese over time and the stability of anxiety across English and Japanese. Chinese university students (N…

"¿Tu te Acuerdas de Ganchulinas?": Longitudinal Research with Young Emergent Bilinguals

ERIC Educational Resources Information Center

Axelrod, Ysaaca

2014-01-01

Drawing on the work of Celia Genishi, this article discusses data from an ethnographic case study of young Latina/o children, starting in their four-year-olds classroom in a Head Start Program through their first grade year in a dual-language program in a public school. The children attended a bilingual Head Start program that followed a…

Parallel Bimodal Bilingual Acquisition: A Hearing Child Mediated in a Deaf Family

ERIC Educational Resources Information Center

Cramér-Wolrath, Emelie

2013-01-01

The aim of this longitudinal case study was to describe bimodal and bilingual acquisition in a hearing child, Hugo, especially the role his Deaf family played in his linguistic education. Video observations of the family interactions were conducted from the time Hugo was 10 months of age until he was 40 months old. The family language was Swedish…

Skype-Based English Activities: A Case for Compelling Input? Correlational Changes before and after Skype Exchanges

ERIC Educational Resources Information Center

Ockert, David

2015-01-01

This paper reports the results of a small, longitudinal study involving a group of Japanese elementary school students (N = 29) involved in exploratory research using foreign language activities, including two Skype exchanges between these students and students in Australia. The purpose of the research was to test for the impact of a series of…

A Longitudinal Investigation of the Science Teaching Efficacy Beliefs and Science Experiences of a Cohort of Preservice Elementary Teachers

ERIC Educational Resources Information Center

Deehan, James; Danaia, Lena; McKinnon, David H.

2017-01-01

This paper assesses the relationship between participation in two tertiary science courses and the science teaching efficacy beliefs (STEBs) of one cohort of preservice elementary teachers over a four-year period. Two Type II case studies were conducted within the courses. Data were collected through 26 administrations of the Science Teaching…

Optimizing the longitudinal and transverse electroosmotic pumping in a rectangular channel with horizontal baffle plates

NASA Astrophysics Data System (ADS)

Lai, Anison K. R.; Chang, Chien-Cheng; Wang, Chang-Yi

2018-04-01

This paper presents a continued study to our previous work on electroosmotic (EO) flow in a channel with vertical baffle plates by further investigating EO flow through an array of baffle plates arranged in parallel to the channel walls. The flow may be driven either in the direction along or in the direction transverse to the plates, thus distinguishing the longitudinal EO pumping (LEOP) and the transverse EO pumping (TEOP). In both types of EO pumping, it is more interesting to examine the cases when the baffle plates develop a higher zeta potential (denoted by α) than that on the channel walls (β). This semi-analytical study enables us to compare between LEOP and TEOP in the pumping efficiency under similar conditions. The TEOP case is more difficult to solve due to the higher order governing partial differential equations caused by the induced non-uniform pressure gradient distribution. In particular, we examine how the EO pumping rates deviate from those predicted by the Helmholtz-Smoluchowski velocity and illustrate the general trend of optimizing the EO pumping rates with respect to the physical and geometric parameters involved.

Effects of warm water inflows on the dispersion of pollutants in small reservoirs.

PubMed

Palancar, María C; Aragón, José M; Sánchez, Fernando; Gil, Roberto

2006-11-01

The effects of the warm water discharged by a nuclear power plant (NPP) into a small reservoir are studied. A case study is presented (José Cabrera NPP-Zorita Hidráulica Reservoir) with experimental data of the reservoir stratification and predicted data of the dispersion of radioactive pollutants from operative or accidental releases. The vertical and longitudinal temperature profiles, electrical conductivity and transparency of the reservoir water were measured for an annual cycle. The results indicate that the continuous warm water discharge from the NPP causes permanent and artificial reservoir stratification. The stratification is significant within 1500 m upstream and 1000 m downstream from the warm water outfall. The pollutant dispersion has been predicted by using a flow model based on N(T) perfect-mixing compartments in series with feedback. The model parameter, N(T), is calculated from the longitudinal diffusion coefficient. The prediction of pollutant dispersion by means of this model shows that the stratification slows down the vertical mixing in the whole water body, and reduces the reservoir volume that is effective for the dilution and dispersion of pollutants. This means that, in the case of a radioactive pollutant release, the reservoir radioactivity level could increase significantly.

A multimodal neuroimaging study of a case of crossed nonfluent/agrammatic primary progressive aphasia.

PubMed

Spinelli, Edoardo G; Caso, Francesca; Agosta, Federica; Gambina, Giuseppe; Magnani, Giuseppe; Canu, Elisa; Blasi, Valeria; Perani, Daniela; Comi, Giancarlo; Falini, Andrea; Gorno-Tempini, Maria Luisa; Filippi, Massimo

2015-10-01

Crossed aphasia has been reported mainly as post-stroke aphasia resulting from brain damage ipsilateral to the dominant right hand. Here, we described a case of a crossed nonfluent/agrammatic primary progressive aphasia (nfvPPA), who developed a corticobasal syndrome (CBS). We collected clinical, cognitive, and neuroimaging data for four consecutive years from a 55-year-old right-handed lady (JV) presenting with speech disturbances. 18-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) and DaT-scan with (123)I-Ioflupane were obtained. Functional MRI (fMRI) during a verb naming task was acquired to characterize patterns of language lateralization. Diffusion tensor MRI was used to evaluate white matter damage within the language network. At onset, JV presented with prominent speech output impairment and right frontal atrophy. After 3 years, language deficits worsened, with the occurrence of a mild agrammatism. The patient also developed a left-sided mild extrapyramidal bradykinetic-rigid syndrome. The clinical picture was suggestive of nfvPPA with mild left-sided extrapyramidal syndrome. At this time, voxel-wise SPM analyses of (18)F-FDG PET and structural MRI showed right greater than left frontal hypometabolism and damage, which included the Broca's area. DaT-scan showed a reduced uptake in the right striatum. FMRI during naming task demonstrated bilateral language activations, and tractography showed right superior longitudinal fasciculus (SLF) involvement. Over the following year, JV became mute and developed frank left-sided motor signs and symptoms, evolving into a CBS clinical picture. Brain atrophy worsened in frontal areas bilaterally, and extended to temporo-parietal regions, still with a right-sided asymmetry. Tractography showed an extension of damage to the left SLF and right inferior longitudinal fasciculus. We report a case of crossed nfvPPA followed longitudinally and studied with advanced neuroimaging techniques. The results highlight a complex interaction between individual premorbid developmental differences and the clinical phenotype.

78 FR 15279 - Airworthiness Directives; Airbus Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-11

... altimeter with engaged flare and retard mode, in case of go-around, might lead to a temporary loss of... flare and retard mode, in case of go-around, the situation may lead to a temporary loss of aeroplane... and retard mode, in case of go-around, might lead to a temporary loss of airplane longitudinal control...

FUEL ROD CLUSTERS

DOEpatents

Schultz, A.B.

1959-08-01

A cluster of nuclear fuel rods and a tubular casing therefor through which a coolant flows in heat-exchange contact with the fuel rods is described. The fuel rcds are held in the casing by virtue of the compressive force exerted between longitudinal ribs of the fuel rcds and internal ribs of the casing or the internal surfaces thereof.

Description of congenital hand anomalies: a personal view.

PubMed

Tonkin, M A

2006-10-01

A series of four congenital hand cases exhibiting central clefting are presented. The cases are morphologically similar and exhibit characteristics of both symbrachydactyly and central longitudinal deficiency. The cases demonstrate difficulties in classification by either the IFSSH classification system or the JSSH modification of it. An alternative descriptive approach to classification is suggested.

Longitudinal assessment of childhood optic gliomas: relationship between flicker visual evoked potentials and magnetic resonance imaging findings.

PubMed

Falsini, Benedetto; Ziccardi, Lucia; Lazzareschi, Ilaria; Ruggiero, Antonio; Placentino, Luca; Dickmann, Anna; Liotti, Lucia; Piccardi, Marco; Balestrazzi, Emilio; Colosimo, Cesare; Di Rocco, Concezio; Riccardi, Riccardo

2008-05-01

The aim of this study was to evaluate longitudinally functional and neuro-radiologic findings in childhood optic gliomas (OG), by comparing flicker visual evoked potentials (F-VEPs) with brain magnetic resonance imaging (MRI) changes. Fourteen children (age range: 1-13 years) with OGs underwent serial F-VEP, MRI and neuro-ophthalmic examinations over a 38 month (median, range: 6-76) follow-up. F-VEPs were elicited by 8 Hz sine-wave flicker stimuli presented in a mini-Ganzfeld. Contrast-enhanced MRI examinations were performed. Results of both tests were blindly assessed by independent evaluators. F-VEPs were judged to be improved, stable or worsened if changes in the amplitude and/or phase angle of the response exceeded the limits of test-retest variability (+/-90th percentile) established for the same patients. MRI results were judged to show regression, stabilization or progression of OG based on its changes in size (+/-20%) or extension. Two to seven pairs of F-VEP/MRI examinations per patient (median: 4) were collected. Based on a total of 38 pairs of F-VEP/MRI examinations, both tests agreed in showing worsening (progression), stabilization and improvement (regression) in 5, 15 and 10 cases, respectively. In 3 cases, F-VEPs showed a worsening and MRI a stabilization, while in 5 cases F-VEPs showed an improvement and MRI a stabilization. Agreement between F-VEP and MRI changes was 78.9% (95% CI: +/- 37%, K statistics = 0.67, P < 0.001). The results indicate that longitudinal F-VEP changes can predict changes in MRI-assessed OG size and extension, providing a non-invasive functional assay, complementary to neuro-imaging, for OG follow-up.

Effectiveness and Value of Prophylactic 5-Layer Foam Sacral Dressings to Prevent Hospital-Acquired Pressure Injuries in Acute Care Hospitals

PubMed Central

2017-01-01

PURPOSE: The purpose of this study was to examine the effectiveness and value of prophylactic 5-layer foam sacral dressings to prevent hospital-acquired pressure injury rates in acute care settings. DESIGN: Retrospective observational cohort. SAMPLE AND SETTING: We reviewed records of adult patients 18 years or older who were hospitalized at least 5 days across 38 acute care hospitals of the University Health System Consortium (UHC) and had a pressure injury as identified by Patient Safety Indicator #3 (PSI-03). All facilities are located in the United States. METHODS: We collected longitudinal data pertaining to prophylactic 5-layer foam sacral dressings purchased by hospital-quarter for 38 academic medical centers between 2010 and 2015. Longitudinal data on acute care, hospital-level patient outcomes (eg, admissions and PSI-03 and pressure injury rate) were queried through the UHC clinical database/resource manager from the Johns Hopkins Medicine portal. Data on volumes of dressings purchased per UHC hospital were merged with UHC data. Mixed-effects negative binomial regression was used to test the longitudinal association of prophylactic foam sacral dressings on pressure injury rates, adjusted for hospital case-mix and Medicare payments rules. RESULTS: Significant pressure injury rate reductions in US acute care hospitals between 2010 and 2015 were associated with the adoption of prophylactic 5-layer foam sacral dressings within a prevention protocol (−1.0 cases/quarter; P = .002) and changes to Medicare payment rules in 2014 (−1.13 cases/quarter; P = .035). CONCLUSIONS: Prophylactic 5-layer foam sacral dressings are an effective component of a pressure injury prevention protocol. Hospitals adopting these technologies should expect good value for use of these products. PMID:28816929

[Child abuse in Tlaxcala: a case-control study].

PubMed

Herrada-Huidobro, A; Nazar-Beutelspacher, A; Cassaball-Núñez, M; Vega-Ramos, R; Nava-Cruz, C B

1992-01-01

A longitudinal, retrospective and descriptive study about child abuse was carried out in the Hospitals of the Tlaxcala Secretariat of Health, Mexico. The information was obtained from hospitalized children's charts between January first and November 30, 1991. The charts included were those belonging to zero to 14 year old children with injuries, poisoning, and II-III degrees of malnutrition. Four child-abuse criteria were established: physical, sexual, non organic malnutrition and mixed (physical and non organic malnutrition). Two control groups were defined. Different patterns were observed between accidental and non accidental injuries, malnutrition and poisoning among the case and the control groups. The study provides useful information for the integral diagnosis of child abuse in hospitalized children.

Estimating the extent of household contact misclassification with index cases of disease in longitudinal studies using a stochastic simulation model.

PubMed

Chirwa, Tobias; Floyd, Sian; Fine, Paul

2013-01-24

Household contact with an index case of an infectious disease is a known risk factor for infection transmission. However, such contact may be underestimated due to the dynamic nature of households, particularly in longitudinal studies. Such studies generally begin with contact defined at a single point in time ('snap-shot'), leading to contact misclassification for some individuals who actually experienced contact before and after the snapshot. To quantify contact misclassification with index cases of disease in households. Historical data of 112,026 individuals from 17,889 households from an epidemiological study on leprosy in northern Malawi were used. Individuals were interviewed in the early 1980s and followed up over 5 years. It was possible to trace whether individuals died, changed household within the area, or moved out of the area between the two surveys.Using a 10% sample of households as the starting population and parameters for demographic and household changes over 5 years, the extent of contact misclassification was estimated through a simulation model of household dynamics, which traced contact with index cases in households over time. The model thereafter compared initial contact status and 'true' contact status generated from simulations. The starting population had 11,401 individuals, 52% female, and 224 (2%) leprosy index cases. Eleven percent of the households had at least one index case resident and 10% (1, 177) of non-case individuals were initial contacts. Sensitivity of initial contact status ranged from 0.52 to 0.74 and varied by age and sex. Sensitivity was low in those aged 20-29 and under 5 years but high in 5- to 14-year-olds. By gender, there were no differences among those aged under 5; females had lower sensitivity among those aged under 20 and higher for those above 30, respectively. Sensitivity was also low in simulations of long incubation periods. This work demonstrates the implications of changes in households on household contact-associated disease spread, particularly for long durations of follow-up and infections with long incubation periods where earlier unobserved contact is critical.

A longitudinal study of self-control at the transition to secondary school: Considering the role of pubertal status and parenting.

PubMed

Ng-Knight, Terry; Shelton, Katherine H; Riglin, Lucy; McManus, I C; Frederickson, Norah; Rice, Frances

2016-07-01

Higher self-control in children and adolescents is associated with a range of positive outcomes in adulthood. However, little is known about the naturalistic development of self-control during early adolescence and the factors that affect this. We examined the role of puberty and parenting style as theoretically important influences on stability and change in self-control. A longitudinal (3 waves), multiple-informant dataset of children entering early adolescence (M = 11 years) was used to explore longitudinal change in self-control using latent growth curve modelling. Children's self-control declined during the one-year study period and declines were associated with children's behavioural and social functioning. Associations with self-control were found for pubertal status and parental warmth and hostility, but not for parental discipline. The findings suggest that during early adolescence, when children make the transition to secondary school, self-control declines. This is particularly the case for those experiencing puberty earlier than their peers. Parent warmth influences the trajectory of self-control during this period. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

The Real-World Problem of Care Coordination: A Longitudinal Qualitative Study with Patients Living with Advanced Progressive Illness and Their Unpaid Caregivers

PubMed Central

Daveson, Barbara A.; Harding, Richard; Shipman, Cathy; Mason, Bruce L.; Epiphaniou, Eleni; Higginson, Irene J.; Ellis-Smith, Clare; Henson, Lesley; Munday, Dan; Nanton, Veronica; Dale, Jeremy R.; Boyd, Kirsty; Worth, Allison; Barclay, Stephen; Donaldson, Anne; Murray, Scott

2014-01-01

Objectives To develop a model of care coordination for patients living with advanced progressive illness and their unpaid caregivers, and to understand their perspective regarding care coordination. Design A prospective longitudinal, multi-perspective qualitative study involving a case-study approach. Methods Serial in-depth interviews were conducted, transcribed verbatim and then analyzed through open and axial coding in order to construct categories for three cases (sites). This was followed by continued thematic analysis to identify underlying conceptual coherence across all cases in order to produce one coherent care coordination model. Participants Fifty-six purposively sampled patients and 27 case-linked unpaid caregivers. Settings Three cases from contrasting primary, secondary and tertiary settings within Britain. Results Coordination is a deliberate cross-cutting action that involves high-quality, caring and well-informed staff, patients and unpaid caregivers who must work in partnership together across health and social care settings. For coordination to occur, it must be adequately resourced with efficient systems and services that communicate. Patients and unpaid caregivers contribute substantially to the coordination of their care, which is sometimes volunteered at a personal cost to them. Coordination is facilitated through flexible and patient-centered care, characterized by accurate and timely information communicated in a way that considers patients’ and caregivers’ needs, preferences, circumstances and abilities. Conclusions Within the midst of advanced progressive illness, coordination is a shared and complex intervention involving relational, structural and information components. Our study is one of the first to extensively examine patients’ and caregivers’ views about coordination, thus aiding conceptual fidelity. These findings can be used to help avoid oversimplifying a real-world problem, such as care coordination. Avoiding oversimplification can help with the development, evaluation and implementation of real-world coordination interventions for patients and their unpaid caregivers in the future. PMID:24788451

Analyzing the Behavioral Differences between Students of Different Genders, Prior Knowledge and Learning Performance with an Educational MMORPG: A Longitudinal Case Study in an Elementary School

ERIC Educational Resources Information Center

Hou, Huei-Tse

2013-01-01

Many researchers have studied the effects of game-based learning (GBL) (eg, Annetta, Minogu, Holmes & Cheng, 2009; Kiili, 2007). However, empirical process analyses of long-term applications of GBL in a school setting are much less common. A process analysis of GBL in a school setting allows us to better understand the role of games in…

Longitudinal experiences of children remaining at home after a first-time investigation for suspected maltreatment

PubMed Central

Campbell, Kristine A.; Thomas, Andrea M.; Cook, Lawrence J.; Keenan, Heather T.

2012-01-01

Objective To describe longitudinal change in risk for children remaining at home following a first-time investigation for suspected maltreatment. Study design A retrospective cohort study of children remaining at home following first-time investigation for maltreatment using a nationally representative sample of households involved with Child Protective Services (CPS). Outcomes include poverty, social support, caregiver depression, intimate partner violence (IPV), drug/alcohol dependence, corporal punishment, and child behavior problems at baseline, 18, and 36 months following first-time CPS investigation. We present longitudinal models to 1) estimate prevalence of risk factors at each timepoint and 2) examine associations between risk-specific service referrals and longitudinal change in risk factor prevalence. Results Our sample represented 1,057,056 U.S. children remaining at home following first-time investigation for maltreatment. Almost 100,000 (9.2%) children experienced out-of-home placement within 36 months. The prevalence of poverty (44.3%), poor social support (36.3%), caregiver depression (24.4%), IPV (22.1%), and internalizing (30.0%) and externalizing (35.8%) child behavior problems was above general population prevalence at baseline and remained high over the next 36 months. Referral to risk-specific services occurred in a minority of cases, but was associated with significant longitudinal reductions in IPV, drug/alcohol dependence, and externalizing child behavior problems. Conclusions Children remaining at home following a first-time investigation for maltreatment live with persistent risk factors for repeat maltreatment. Appropriate service referrals are uncommon, but may be associated with meaningful reduction in risk over time. Pediatricians and policy makers may be able to improve outcomes in these families with appropriate service provision and referrals. PMID:22480699

Midlife C-reactive protein and risk of cognitive decline: a 31-year follow-up.

PubMed

Laurin, Danielle; David Curb, J; Masaki, Kamal H; White, Lon R; Launer, Lenore J

2009-11-01

There is evidence for a relationship between raised inflammatory markers, including high sensitivity C-reactive protein (hs-CRP), measured late in life, and an increased risk of cognitive decline and dementia. This study evaluates the association of midlife hs-CRP concentrations with late-life longitudinal trends in cognitive function. Data are from the Honolulu-Asia Aging Study (HAAS), a longitudinal community-based study of Japanese American men. hs-CRP levels were measured on average 25 years before cognitive testing began in 1991. Subjects were followed from up to three follow-up examinations (mean of 6.1 years). At each exam, cognitive function was measured with the Cognitive Abilities Screening Instrument (CASI). This analysis includes a sub-sample of 691 subjects dementia-free in 1991. With incident dementia cases included, those with the highest quartile of hs-CRP had significantly more cognitive decline than those in the lowest quartile, after adjustment for baseline CASI score, demographic and cardiovascular risk factors. When cases were removed, there was no difference in cognitive decline by CRP quartile. This relationship was not modified by the presence of apolipoprotein E varepsilon4. These findings suggest that inflammatory mechanisms during midlife may reflect underlying processes contributing to dementia-related cognitive decline late in life.

Quantitative Relationship Between Cumulative Risk Alleles Based on Genome-Wide Association Studies and Type 2 Diabetes Mellitus: A Systematic Review and Meta-analysis.

PubMed

Kodama, Satoru; Fujihara, Kazuya; Ishiguro, Hajime; Horikawa, Chika; Ohara, Nobumasa; Yachi, Yoko; Tanaka, Shiro; Shimano, Hitoshi; Kato, Kiminori; Hanyu, Osamu; Sone, Hirohito

2018-01-05

Many epidemiological studies have assessed the genetic risk of having undiagnosed or of developing type 2 diabetes mellitus (T2DM) using several single nucleotide polymorphisms (SNPs) based on findings of genome-wide association studies (GWAS). However, the quantitative association of cumulative risk alleles (RAs) of such SNPs with T2DM risk has been unclear. The aim of this meta-analysis is to review the strength of the association between cumulative RAs and T2DM risk. Systematic literature searches were conducted for cross-sectional or longitudinal studies that examined odds ratios (ORs) for T2DM in relation to genetic profiles. Logarithm of the estimated OR (log OR) of T2DM for 1 increment in RAs carried (1-ΔRA) in each study was pooled using a random-effects model. There were 46 eligible studies that included 74,880 cases among 249,365 participants. In 32 studies with a cross-sectional design, the pooled OR for T2DM morbidity for 1-ΔRA was 1.16 (95% confidence interval [CI], 1.13-1.19). In 15 studies that had a longitudinal design, the OR for incident T2DM was 1.10 (95% CI, 1.08-1.13). There was large heterogeneity in the magnitude of log OR (P < 0.001 for both cross-sectional studies and longitudinal studies). The top 10 commonly used genes significantly explained the variance in the log OR (P = 0.04 for cross-sectional studies; P = 0.006 for longitudinal studies). The current meta-analysis indicated that carrying 1-ΔRA in T2DM-associated SNPs was associated with a modest risk of prevalent or incident T2DM, although the heterogeneity in the used genes among studies requires us to interpret the results with caution.

Quantitative Relationship Between Cumulative Risk Alleles Based on Genome-Wide Association Studies and Type 2 Diabetes Mellitus: A Systematic Review and Meta-analysis

PubMed Central

Kodama, Satoru; Fujihara, Kazuya; Ishiguro, Hajime; Horikawa, Chika; Ohara, Nobumasa; Yachi, Yoko; Tanaka, Shiro; Shimano, Hitoshi; Kato, Kiminori; Hanyu, Osamu; Sone, Hirohito

2018-01-01

Many epidemiological studies have assessed the genetic risk of having undiagnosed or of developing type 2 diabetes mellitus (T2DM) using several single nucleotide polymorphisms (SNPs) based on findings of genome-wide association studies (GWAS). However, the quantitative association of cumulative risk alleles (RAs) of such SNPs with T2DM risk has been unclear. The aim of this meta-analysis is to review the strength of the association between cumulative RAs and T2DM risk. Systematic literature searches were conducted for cross-sectional or longitudinal studies that examined odds ratios (ORs) for T2DM in relation to genetic profiles. Logarithm of the estimated OR (log OR) of T2DM for 1 increment in RAs carried (1-ΔRA) in each study was pooled using a random-effects model. There were 46 eligible studies that included 74,880 cases among 249,365 participants. In 32 studies with a cross-sectional design, the pooled OR for T2DM morbidity for 1-ΔRA was 1.16 (95% confidence interval [CI], 1.13–1.19). In 15 studies that had a longitudinal design, the OR for incident T2DM was 1.10 (95% CI, 1.08–1.13). There was large heterogeneity in the magnitude of log OR (P < 0.001 for both cross-sectional studies and longitudinal studies). The top 10 commonly used genes significantly explained the variance in the log OR (P = 0.04 for cross-sectional studies; P = 0.006 for longitudinal studies). The current meta-analysis indicated that carrying 1-ΔRA in T2DM-associated SNPs was associated with a modest risk of prevalent or incident T2DM, although the heterogeneity in the used genes among studies requires us to interpret the results with caution. PMID:29093303

Congenital syphilis: refining newborn evaluation and management in Shenzhen, southern China.

PubMed

Wu, Da-Dong; Hong, Fu-Chang; Feng, Tie-Jian; Liu, Xiao-Li; Lin, Li-Jun; Tian, Li-Shan; Qiu, Li-Xia

2010-08-01

Consistent definitions of congenital syphilis are critical for determining true incidences and setting up targets of elimination. This study aimed to assess the evaluation and management of infants at high risk of congenital syphilis with an antenatal syphilis-screening programme in the Shenzhen SEZ and to develop feasible definitions for the detection of congenital syphilis in China. A retrospective study was conducted of all standardised records of pregnant women with positive syphilis between 2003 and 2007. Infants at high risk of congenital syphilis were evaluated by laboratory tests at birth and longitudinal follow-up. A screening test-positive congenital syphilis case was defined based on a positive 19S-IgM-FTA-ABS result at birth. Assuming that 19S-IgM-FTA-ABS was the gold standard, the sensitivity and specificity of the ascertainment methods were calculated. During the study period, 1010 live infants were born to women with active syphilis during pregnancy. 19S-IgM-FTA-ABS detected 42 screening-positive congenital syphilis cases and another nine cases were identified by longitudinal follow-up only. Using 19S-IgM-FTA-ABS as the gold standard, 'fourfold rapid plasma reagin (RPR) titres' had the highest sensitivity and specificity compared with the other two follow-up methods. 19S-IgM-FTA-ABS makes congenital syphilis case classification simpler and faster for newborns. In areas where 19S-IgM-FTA-ABS is not available, comparing newborn RPR titres with maternal titres can be an alternative method. Meanwhile, positive follow-up results act as treatment indicators for older infants. As congenital syphilis definitions vary over the country, the Shenzhen programme suggested a practical model for surveillance and treatment in areas with or without available 19S-IgM-FTA-ABS testing.

Cervical spine injuries in suicidal hanging without a long-drop--patterns and possible underlying mechanisms of injury: an autopsy study.

PubMed

Nikolić, Slobodan; Zivković, Vladimir

2014-06-01

The incidence of cervical spine injuries in suicidal hangings with a short-drop has been reported to be extremely low or non-existent. The aim of this study was to determine the frequency and pattern of cervical spine injuries in suicidal hanging. A retrospective autopsy study was performed and short-drop suicidal hanging cases with documented cervical spine injuries were identified. This group was further analyzed with regard to the gender and age of the deceased, the position of the ligature knot, the presence of hyoid-laryngeal fractures, and the level of cervical spine injury. Cervical spine injuries were present in 25 of the 766 cases, with an average age of 71.9 ± 10.7 years (range 39-88 years). In 16 of these 25 cases, the ligature knot was in the anterior position. The most common pattern of cervical spine injury included partial or complete disruption of the anterior longitudinal ligament and widening of the lower cervical spine disk spaces, associated with absence of hyoid-laryngeal fractures. Cervical spine injuries are not commonly found in short-drop suicidal hanging, occurring in only 3.3 % of all observed cases. Cervical spine injury may be occurring in 80 % of subjects aged 66.5 years and above. The most common pattern of cervical spine injury included anterior longitudinal ligament disruption of the lower cervical spine, disk space widening, and no vertebral body displacement. These injuries were mainly associated with an anterior knot position, and may be a consequence of loop pressure to the posterior neck and cervical spine hyperextension.

Evaluation of longitudinal tracking and data mining for an imaging informatics-based multiple sclerosis e-folder (Conference Presentation)

NASA Astrophysics Data System (ADS)

Ma, Kevin C.; Forsyth, Sydney; Amezcua, Lilyana; Liu, Brent J.

2017-03-01

We have designed and developed a multiple sclerosis eFolder system for patient data storage, image viewing, and automatic lesion quantification results to allow patient tracking. The web-based system aims to be integrated in DICOM-compliant clinical and research environments to aid clinicians in patient treatments and data analysis. The system quantifies lesion volumes, identify and register lesion locations to track shifts in volume and quantity of lesions in a longitudinal study. We aim to evaluate the two most important features of the system, data mining and longitudinal lesion tracking, to demonstrate the MS eFolder's capability in improving clinical workflow efficiency and outcome analysis for research. In order to evaluate data mining capabilities, we have collected radiological and neurological data from 72 patients, 36 Caucasian and 36 Hispanic matched by gender, disease duration, and age. Data analysis on those patients based on ethnicity is performed, and analysis results are displayed by the system's web-based user interface. The data mining module is able to successfully separate Hispanic and Caucasian patients and compare their disease profiles. For longitudinal lesion tracking, we have collected 4 longitudinal cases and simulated different lesion growths over the next year. As a result, the eFolder is able to detect changes in lesion volume and identifying lesions with the most changes. Data mining and lesion tracking evaluation results show high potential of eFolder's usefulness in patientcare and informatics research for multiple sclerosis.

The Effects of Mediated Exposure to Ethnic-Political Violence on Middle East Youth’s Subsequent Post-Traumatic Stress Symptoms and Aggressive Behavior

PubMed Central

Gvirsman, Shira Dvir; Huesmann, L. Rowell; Dubow, Eric F.; Landau, Simha F.; Shikaki, Khalil; Boxer, Paul

2015-01-01

This study introduces the concept of chronic (i.e., repeated and cumulative) mediated exposure to political violence and investigates its effects on aggressive behavior and post-traumatic stress (PTS) symptoms in young viewers. Embracing the risk-matrix approach, these effects are studied alongside other childhood risk factors that influence maladjustment. A longitudinal study was conducted on a sample of youth who experience the Israeli-Palestinian conflict firsthand (N = 1,207). As hypothesized, higher levels of chronic mediated exposure were longitudinally related to higher levels of PTS symptoms and aggression at peers independently of exposure to violence in other contexts. In the case of aggressive behavior, structural equation analysis (SEM) analyses suggest that, while it is likely there are causal effects in both directions, the bigger effect is probably for exposure to violence stimulating aggression than for aggression stimulating exposure to violence. Both the longitudinal effects on aggression and PTS symptoms were especially strong among youth who demonstrated initially higher levels of the same type of maladjustment. These results support the conceptualization of the relation between media violence and behaviors as “reciprocally determined” or “downward spirals” and highlight the contribution of the risk-matrix approach to the analysis of childhood maladjustment. PMID:26456988

Genetic erosion in maize’s center of origin

PubMed Central

Dyer, George A.; López-Feldman, Alejandro; Yúnez-Naude, Antonio; Taylor, J. Edward

2014-01-01

Crop genetic diversity is an indispensable resource for farmers and professional breeders responding to changing climate, pests, and diseases. Anecdotal appraisals in centers of crop origin have suggested serious threats to this diversity for over half a century. However, a nationwide inventory recently found all maize races previously described for Mexico, including some formerly considered nearly extinct. A flurry of social studies seems to confirm that farmers maintain considerable diversity. Here, we compare estimates of maize diversity from case studies over the past 15 y with nationally and regionally representative matched longitudinal data from farmers across rural Mexico. Our findings reveal an increasing bias in inferences based on case study results and widespread loss of diversity. Cross-sectional, case study data suggest that farm-level richness has increased by 0.04 y−1 nationwide; however, direct estimates using matched longitudinal data reveal that richness dropped −0.04 y−1 between 2002 and 2007, from 1.43 to 1.22 varieties per farm. Varietal losses occurred across regions and altitudinal zones, and regardless of farm turnover within the sector. Extinction of local maize populations may not have resulted in an immediate loss of alleles, but low varietal richness and changes in maize’s metapopulation dynamics may prevent farmers from accessing germplasm suitable to a rapidly changing climate. Declining yields could then lead farmers to leave the sector and result in a further loss of diversity. Similarities in research approaches across crops suggest that methodological biases could conceal a loss of diversity at other centers of crop origin. PMID:25197088

Dizziness and Head Injury

PubMed Central

Barber, H. O.

1965-01-01

Dizziness, whether vague or specifically rotational, is a common sequel to head injury, and is often postural. One hundred and sixty-five patients with this symptom were examined. The simple posture tests employed to detect positional nystagmus are described. This physical finding was present in one-quarter of the entire group, and in nearly one-half of cases of longitudinal fracture of temporal bone. In such cases, it is an objective finding that corresponds precisely to the patient's complaint of vertigo. Transverse fracture of temporal bone destroys the inner ear in both cochlear and vestibular parts. Longitudinal fracture is commoner and causes bleeding from the ear; inner-ear damage is usually minor. In the rare cases where persisting postural vertigo and positional nystagmus are disabling, relief of the symptom may be achieved by vestibular denervation of the affected side. PMID:14285289

Determinants of response in a longitudinal health study following the firework-disaster in Enschede, The Netherlands.

PubMed

Dijkema, Marieke B A; Grievink, Linda; Stellato, Rebecca K; Roorda, Jan; van der Velden, Peter G

2005-01-01

Very few longitudinal health studies after disasters published data on the determinants of loss to follow up. However, these determinants provide important information for future disaster studies to improve their response and reduce selection bias. For this purpose we analyzed the data of a longitudinal health survey which was performed among residents and emergency workers, at 3 weeks (n = 3662) and at 18 months (n = 2769) after a major firework disaster in The Netherlands (Enschede, May 13, 2000). The response was lower among immigrants (54%) than among native Dutch (81%). Severe damage to the house due to the disaster (OR: 1.8; 95% CI: 1.1-3.0) and being involved as an emergency workers (OR: 2.1; 95% CI: 1.2-3.4) were associated with higher response among native Dutch, while this was not the case among immigrants. Non-western immigrants with health problems in the first study were more likely to participate in the second study (for example physical symptoms OR: 2.5: 95% CI: 1.4-4.4), while the native Dutch with these symptoms were less likely to participate (OR: 0.7; 95% CI: 0.5-0.9). In conclusion, disaster-related characteristics were associated with higher response in native Dutch. Health problems were associated with higher response among non-western immigrants and with lower response among the native Dutch.

Recurrent longitudinal extensive transverse myelitis in a neuro-Behçet syndrome treated with infliximab

PubMed Central

Uygunoğlu, Uğur; Pasha, Maarya; Saip, Sabahattin; Siva, Aksel

2015-01-01

Background Spinal cord involvement is not common, but can be seen in neuro-Behçet's syndrome (NBS). The major site of involvement is the cervical spinal cord with the myelitis-like inflammatory lesions continuing more than two segments, and extending to the brainstem. Case A 30-year-old male patient who has been followed with a diagnosis of Behçet's syndrome admitted to our neurology department clinically and radiologically suggestive of recurrent and extensive longitudinal myelitis. His anti-aquaporine antibody was negative. Because of insufficient effect of azathioprine, cyclophosphamide, and corticosteroids, infliximab was started. His clinical and radiological status is stationary for 3 years under infliximab treatment. Discussion Myelitis such as that occurring in our patient may have a similar presentation like neuromyelitis optica (NMO), which should therefore be included in differential diagnosis. Myelitis observed in both NMO and NBS shows spinal cord lesions longer than three or more vertebrae. Anti-aquaporine antibody must be evaluated in all patients presenting with longitudinal myelitis. Anti-tumor necrosis factor agent infliximab might be an alternative treatment in severe form of NBS such as myelitis. Conclusion In our case, successful treatment of recurrent and extensive longitudinal transverse myelitis in NBS with infliximab was demonstrated. PMID:24673549

Changes in cognitive control in pre-manifest Huntington's disease examined using pre-saccadic EEG potentials - a longitudinal study.

PubMed

Ness, Vanessa; Bestgen, Anne-Kathrin; Saft, Carsten; Beste, Christian

2014-01-01

It is well-known that Huntington's disease (HD) affects saccadic processing. However, saccadic dysfunctions in HD may be seen as a result of dysfunctional processes occurring at the oculomotor level prior to the execution of saccades, i.e., at a pre-saccadic level. Virtually nothing is known about possible changes in pre-saccadic processes in HD. This study examines pre-saccadic processing in pre-manifest HD gene mutation carriers (pre-HDs) by using clinically available EEG measures. Error rates, pre-saccadic EEG potentials and saccade onset EEG potentials were measured in 14 pre-HDs and case-matched controls performing prosaccades and antisaccades in a longitudinal study over a 15-month period. The results show that pre-saccadic potentials were changed in pre-HDs, relative to controls and also revealed changes across the 15-month longitudinal period. In particular, pre-saccadic ERP in pre-HDs were characterized by lower amplitudes and longer latencies, which revealed longitudinal changes. These changes were observed for anti-saccades, but not for pro-saccades. Overt saccadic trajectories (potentials) were not different to those in controls, showing that pre-saccadic processes are sensitive to subtle changes in fronto-striatal networks in pre-HDs. Deficits in pre-saccadic processes prior the execution of an erroneous anti-saccade can be seen as an effect of dysfunctional cognitive control in HD. This may underlie saccadic abnormalities and hence a major phenotype of HD. Pre-saccadic EEG potentials preceding erroneous anti-saccades are sensitive to pre-manifest disease progression in HD.

Longitudinal Assessment of Health-Related Quality of Life following Adolescent Sports-Related Concussion.

PubMed

Russell, Kelly; Selci, Erin; Chu, Stephanie; Fineblit, Samuel; Ritchie, Lesley; Ellis, Michael J

2017-07-01

To examine initial and longitudinal health-related quality of life (HRQOL) in adolescent sports-related concussion (SRC) patients, a prospective observational case-series study was conducted among adolescent SRC patients who were evaluated at a multi-disciplinary pediatric concussion program. Health-related quality of life was measured using the child self-report Pediatric Quality of Life Inventory (PedsQL) generic score scale (age 13-18 version) and the PedsQL Cognitive Functioning scale. Initial and longitudinal HRQOL outcomes were compared between patients who did and did not develop post-concussion syndrome (PCS). A total of 63 patients met the inclusion criteria during the study period. The mean age of the cohort was 14.57 years (standard deviation, 1.17) and 61.9% were male. The median time from injury to initial consultation was 6.5 days (interquartile range, 5, 11). At initial consultation, impairments in physical and cognitive HRQOL but not social or emotional HRQOL were observed. Initial symptom burden and length of recovery were associated with greater impairment in physical and cognitive HRQOL. Patients who went on to develop PCS had significantly worse physical and cognitive HRQOL at initial consultation and demonstrated a slower rate of recovery in these domains, compared with those who recovered in less than 30 days. Adolescent SRC was associated with HRQOL impairments that correlated with clinical outcomes. No persistent impairments in HRQOL were detected among patients who achieved physician-documented clinical recovery. Future studies are needed to evaluate the clinical utility of HRQOL measurement in the longitudinal management of adolescent SRC and PCS patients.

Glucose tolerance: hypothesis testing on Malaysian diabetic community.

PubMed

Gillani, Syed Wasif; Sari, Yelly Oktavia; Sulaiman, Syed Azhar Syed; Baig, Mirza R

2014-01-01

Our study objective was to evaluate glucose tolerance and effecting factors among diabetes patients' with home care program (PHCP) in Malaysian community. A 24-week longitudinal quasi-experimental -single blind - pre/post-test study design was used to assess the effectiveness of a diabetes education program to enhance self-care practices. An attrition rate of 25% implied longitudinal design of the study in the calculation of sample size. Hence the sample size of the study was 106 subjects (53 cases and 53 focus group). The level of significance was set at 0.05. Ethical clearance had been made prior to conducting this study. Of the 109 subjects who met the study-entry criteria, 3 subjects declined to participate due to lack of time and interest. No significant parameters were revealed in the demographic and clinical characteristics of participants who completed the study. Focus group showed significant reduction in HbA1c value with mean 1.1% as compared to cases with a mean 0.06%. Similarly, hypothesis on self-care management suggest significantly improved practices among focus group [M=2.94, SD=2.25] for case group M=0.47, SD=1.36; t[127.64]=-8.23, p≤0.001] with moderate effect size [eta squared=0.06]. Total physical activity was defined as the combination of non-leisure and leisure activities. There was a statistically significant difference for increase in total physical levels between the focus [M=14.01, SD=6.41] and case groups [13.21, SD=5.22; t[148.04]=-3.15, p=0.002] with no difference in the non-leisure activity [p=0.43]. As for the case group, there was no significant difference in SMBG practices from baseline [M=0.70, SD=1.35] to follow-up [M=0.47, SD=1.36, t[72]=0.97, P=0.34] and no relationship was found between the number of blood glucose tests done with demographic or clinical variables. This study offered improved self-care practices and physical activity after PHCP but with problematic dietary care. This might be due to social and cultural habits among Malaysian population.

Effects of individual-level socioeconomic factors on racial disparities in cancer treatment and survival: findings from the National Longitudinal Mortality Study, 1979-2003.

PubMed

Du, Xianglin L; Lin, Charles C; Johnson, Norman J; Altekruse, Sean

2011-07-15

This is the first study to use the linked National Longitudinal Mortality Study and Surveillance, Epidemiology, and End Results (SEER) data to determine the effects of individual-level socioeconomic factors (health insurance, education, income, and poverty status) on racial disparities in receiving treatment and in survival. This study included 13,234 cases diagnosed with the 8 most common types of cancer (female breast, colorectal, prostate, lung and bronchus, uterine cervix, ovarian, melanoma, and urinary bladder) at age ≥ 25 years, identified from the National Longitudinal Mortality Study-SEER data during 1973 to 2003. Kaplan-Meier methods and Cox regression models were used for survival analysis. Three-year all-cause observed survival for cases diagnosed with local-stage cancers of the 8 leading tumors combined was ≥ 82% regardless of race/ethnicity. More favorable survival was associated with higher socioeconomic status. Compared with whites, blacks were less likely to receive first-course cancer-directed surgery, perhaps reflecting a less favorable stage distribution at diagnosis. Hazard ratio (HR) for cancer-specific mortality was significantly higher among blacks compared with whites (HR, 1.2; 95% confidence interval [CI], 1.1-1.3) after adjusting for age, sex, and tumor stage, but not after further controlling for socioeconomic factors and treatment (HR, 1.0; 95% CI, 0.9-1.1). HRs for all-cause mortality among patients with breast cancer and for cancer-specific mortality in patients with prostate cancer were significantly higher for blacks compared with whites after adjusting for socioeconomic factors, treatment, and patient and tumor characteristics. Favorable survival was associated with higher socioeconomic status. Racial disparities in survival persisted after adjusting for individual-level socioeconomic factors and treatment for patients with breast and prostate cancer. Copyright © 2011 American Cancer Society.

Effect of prospective reimbursement on nursing home costs.

PubMed

Coburn, A F; Fortinsky, R; McGuire, C; McDonald, T P

1993-04-01

This study evaluates the effect of Maine's Medicaid nursing home prospective payment system on nursing home costs and access to care for public patients. The implementation of a facility-specific prospective payment system for nursing homes provided the opportunity for longitudinal study of the effect of that system. Data sources included audited Medicaid nursing home cost reports, quality-of-care data from state facility survey and licensure files, and facility case-mix information from random, stratified samples of homes and residents. Data were obtained for six years (1979-1985) covering the three-year period before and after implementation of the prospective payment system. This study used a pre-post, longitudinal analytical design in which interrupted, time-series regression models were estimated to test the effects of prospective payment and other factors, e.g., facility characteristics, nursing home market factors, facility case mix, and quality of care, on nursing home costs. Prospective payment contributed to an estimated $3.03 decrease in total variable costs in the third year from what would have been expected under the previous retrospective cost-based payment system. Responsiveness to payment system efficiency incentives declined over the study period, however, indicating a growing problem in achieving further cost reductions. Some evidence suggested that cost reductions might have reduced access for public patients. Study findings are consistent with the results of other studies that have demonstrated the effectiveness of prospective payment systems in restraining nursing home costs. Potential policy trade-offs among cost containment, access, and quality assurance deserve further consideration, particularly by researchers and policymakers designing the new generation of case mix-based and other nursing home payment systems.

The longitudinal change of extracellular antioxidant status during pregnancy using an electron spin resonance method.

PubMed

Furukawa, Seishi; Nakajima, Akira; Sameshima, Hiroshi

2016-09-01

To evaluate the longitudinal change of extracellular antioxidant status during pregnancy. A longitudinal study involving 21 cases of pregnant women without medical disorders and had a vaginal birth was undertaken. Blood was obtained at early, mid and late pregnancy, labor onset, and postpartum day 1 and 5. We measured oxygen radical absorbance capacity (ORAC) and superoxide radical-eliminating ability (SREA) in serum using an electron spin resonance method. Twelve healthy volunteers were recruited as controls. Longitudinal and temporal changes were compared. ORAC increased significantly during the antepartum period (at early, mid and late pregnancy), decreased once during the peripartum period (in labor and day 1), and then recovered at day 5. SREA showed a similar tendency as ORAC. Interestingly, the ORAC of controls (919.7 ± 48.2 µmol TE/L) was significantly higher than those pregnant women at early pregnancy (early pregnancy: 699.2 ± 127.5, p < 0.01) and day 1 (740.3 ± 101.0, p < 0.01). The ORAC of controls was comparable to at late pregnancy and day 5 (1066.4 ± 189.6 and 920.3 ± 106.6, respectively). The SREA of controls (77.8 ± 31.2 arbitrary unit) was high, but there was no significant difference against the study group. Antioxidant ability of serum clearly fluctuated during periods that may be critical, namely, early pregnancy and peripartum period.

Outcomes of Left Ventricular Function According to Treatment Response for a Patent Ductus Arteriosus in Preterm Infants

PubMed Central

Cho, Young Sun; Hwang, Seo Jung; Kim, Hyo Jin

2017-01-01

Background To evaluate the outcomes of left ventricular (LV) function according to treatment response for a hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. Methods Echocardiograms of 21 preterm infants born at gestational age < 31 weeks obtained at term-equivalent age were retrospectively studied. Among preterm infants with a hsPDA, 9 underwent ligation after failure of pharmacological closure (ligation group) and 6 experienced successful pharmacological closure (medication group). Six preterm infants without hsPDA (no-hsPDA group) were studied as controls. LV peak longitudinal systolic strain (ε) of each infant was retrospectively obtained from echocardiograms using velocity vector imaging, along with neonatal outcomes. Results Pharmacological closures were attempted at postnatal day 2–3. In the ligation group, the median postnatal age at ligation was 20 days. In the ligation group, LV peak longitudinal systolic ε was significantly decreased at term-equivalent age compared to the other groups. Between the medication and no-hsPDA groups, LV peak longitudinal systolic ε did not differ significantly. Among the neonatal outcomes, infants who experienced necrotizing enterocolitis (NEC) showed significantly decreased LV peak longitudinal systolic ε compared to the infants who did not experience NEC . Conclusion We speculate that in preterm infants with an hsPDA, in cases of medical treatment failure, early PDA ligation at less than 20 days of postnatal age would be beneficial for preserving LV systolic function. PMID:29333220

Improved Doubly Robust Estimation when Data are Monotonely Coarsened, with Application to Longitudinal Studies with Dropout

PubMed Central

Tsiatis, Anastasios A.; Davidian, Marie; Cao, Weihua

2010-01-01

Summary A routine challenge is that of making inference on parameters in a statistical model of interest from longitudinal data subject to drop out, which are a special case of the more general setting of monotonely coarsened data. Considerable recent attention has focused on doubly robust estimators, which in this context involve positing models for both the missingness (more generally, coarsening) mechanism and aspects of the distribution of the full data, that have the appealing property of yielding consistent inferences if only one of these models is correctly specified. Doubly robust estimators have been criticized for potentially disastrous performance when both of these models are even only mildly misspecified. We propose a doubly robust estimator applicable in general monotone coarsening problems that achieves comparable or improved performance relative to existing doubly robust methods, which we demonstrate via simulation studies and by application to data from an AIDS clinical trial. PMID:20731640

Young children's acquisition of knowledge about the Earth: A longitudinal study.

PubMed

Hannust, Triin; Kikas, Eve

2010-10-01

This longitudinal study examined the acquisition of early knowledge of astronomy to determine whether children's knowledge at any point in time is consistent with a naive "mental model." Children were first assessed by means of open questions and drawing tasks at 2 and 3 years of age (N=143). The knowledge was reassessed over the course of the following 3 years. The results showed that although a few indications of naive mental models were found, in most cases young children's knowledge was fragmented and accurate knowledge was often expressed alongside inaccurate/synthetic ideas. Furthermore, it was shown that children need to know scientific facts before they start taking the global perspective when describing the world and, when faced with ambiguous open questions, children often experience difficulties that can induce them to change the types of answers they provide. Copyright 2010 Elsevier Inc. All rights reserved.

Trident sign trumps Aquaporin-4-IgG ELISA in diagnostic value in a case of longitudinally extensive transverse myelitis.

PubMed

Jolliffe, Evan A; Keegan, B Mark; Flanagan, Eoin P

2018-04-21

Longitudinally-extensive T2-hyperintense spinal cord lesions (≥3 vertebral segments) are associated with neuromyelitis optical spectrum disorder but occur with other disorders including spinal cord sarcoidosis. When linear dorsal subpial enhancement is accompanied by central cord/canal enhancement the axial post-gadolinium sequences may reveal a "trident" pattern that has previously been shown to be strongly suggestive of spinal cord sarcoidosis. We report a case in which the patient was initially diagnosed with neuromyelitis optical spectrum disorder, but where the "trident" sign ultimately led to the correct diagnosis of spinal cord sarcoidosis. Copyright © 2018. Published by Elsevier B.V.

Assessing the first wave of epidemiological studies of nanomaterial workers

NASA Astrophysics Data System (ADS)

Liou, Saou-Hsing; Tsai, Candace S. J.; Pelclova, Daniela; Schubauer-Berigan, Mary K.; Schulte, Paul A.

2015-10-01

The results of early animal studies of engineered nanomaterials (ENMs) and air pollution epidemiology suggest that it is important to assess the health of ENM workers. Initial epidemiological studies of workers' exposure to ENMs (<100 nm) are reviewed and characterized for their study designs, findings, and limitations. Of the 15 studies, 11 were cross-sectional, 4 were longitudinal (1 was both cross-sectional and longitudinal in design), and 1 was a descriptive pilot study. Generally, the studies used biologic markers as the dependent variables. All 11 cross-sectional studies showed a positive relationship between various biomarkers and ENM exposures. Three of the four longitudinal studies showed a negative relationship; the fourth showed positive findings after a 1-year follow-up. Each study considered exposure to ENMs as the independent variable. Exposure was assessed by mass concentration in 10 studies and by particle count in six studies. Six of them assessed both mass and particle concentrations. Some of the studies had limited exposure data because of inadequate exposure assessment. Generally, exposure levels were not very high in comparison to those in human inhalation chamber studies, but there were some exceptions. Most studies involved a small sample size, from 2 to 258 exposed workers. These studies represent the first wave of epidemiological studies of ENM workers. They are limited by small numbers of participants, inconsistent (and in some cases inadequate) exposure assessments, generally low exposures, and short intervals between exposure and effect. Still, these studies are a foundation for future work; they provide insight into where ENM workers are experiencing potentially adverse effects that might be related to ENM exposures.

Design and implementation of observational studies to measure disease burden with a focus on stroke.

PubMed

Howard, George; Howard, Virginia J

2018-02-01

Observational epidemiological studies have the dual goals of measuring disease burden and assessing the association between exposures and outcomes. This report focuses on the first of these goals and provides an overview of design considerations of commonly used approaches, specifically community surveillance studies, cross-sectional studies, and longitudinal cohort studies. Each of these designs has strengths and weaknesses, with no study design being superior in all cases. Rather, these designs are complementary to achieve a better understanding of the burden of stroke.

Does relationship satisfaction and financial aid from offspring influence the quality of life of older parents?: a longitudinal study based on findings from the Korean longitudinal study of aging, 2006-2012.

PubMed

Ju, Yeong Jun; Han, Kyu-Tae; Lee, Tae-Hoon; Kim, Woorim; Kim, Juyeong; Park, Eun-Cheol

2016-07-26

Quality of life (QoL) in old age is of major importance because the global population is aging rapidly. Offspring support, including financial and emotional support, is important in later life and directly affects the wellbeing of elderly individuals. The aim of this study was to examine the relationship between QoL in older parents and offspring support. We used baseline data from the 2006-2012 Korean Longitudinal Study of Aging, from 3,274 individuals aged 65 years or older. We measured the individual's QoL using a visual analog scale and included both relationship satisfaction and regular economic support as variables. A generalized estimating equation (GEE) model was used to perform longitudinal regression analysis on the data. Regarding the QoL of older parents, those with an unsatisfying relationship with their offspring had a QoL of -21.93 (SE = 0.55; P < 0.0001) compared to those with satisfying offspring relationships. Those receiving no regular financial aid from their offspring had a QoL of -0.92 (SE = 0.38; P = 0.0171) compared to those who received such economic support. Combination effects were observed, with cases living alone - and having poor offspring relationships and no regular financial support from their offspring - showing the most drastic decrease in QoL (-23.46; SE = 1.03; P < 0.0001). Offspring support influences the QoL of elderly individuals, and Korean children appear to play a crucial role in the QoL of their (older) parents. Considering that the role of offspring is rapidly diminishing due to industrialization policies, initiatives are required to revitalize offspring support for elderly parents.

Early detection of cardiac involvement in sarcoidosis with 2-dimensional speckle-tracking echocardiography.

PubMed

Schouver, Elie-Dan; Moceri, Pamela; Doyen, Denis; Tieulie, Nathalie; Queyrel, Viviane; Baudouy, Delphine; Cerboni, Pierre; Gibelin, Pierre; Leroy, Sylvie; Fuzibet, Jean-Gabriel; Ferrari, Emile

2017-01-15

Cardiac sarcoidosis (CS) is associated with high morbidity and sudden death. The absence of specific symptoms and lack of diagnostic gold standard technique is challenging. New imaging methods could improve the diagnosis of CS. The aim of our study was to assess the role of left ventricular (LV) longitudinal and circumferential strain as estimated by 2D speckle-tracking imaging in patients with diagnosed sarcoidosis without cardiac involvement according to the current guidelines. We investigated the prevalence of LV strain impairment in this population and assessed its relationship with clinical outcomes, composite of mortality, heart failure, arrhythmia and/or secondarily development of CS and cardiac device implantation. We performed a prospective case-control longitudinal study including 35 patients with diagnosed sarcoidosis and normal cardiac function as assessed by standard transthoracic echocardiography and 35 healthy age- and gender-matched controls. All patients underwent a comprehensive echocardiographic study. Mean age of patients was 47.9±14.8years old (22 women). Compared with controls, global LV longitudinal strain (LV GLS) was reduced in sarcoidosis patients: (-17.2±3.1 vs -21.3±1.5%, p<0.0001). Circumferential LV strain was preserved in patients compared to controls (-19.9±-4.3% vs -21.3±1.5%, p=0.12). Impaired LV GLS was significantly associated with clinical outcomes (HR 1.56; [1.16-2.11], p<0.01) on univariate analysis. Speckle-tracking echocardiography revealed decreased longitudinal LV strain in sarcoidosis patients that was associated with outcomes. LV GLS may represent an early marker of myocardial involvement in sarcoidosis patients that needs to be studied further. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

GWAS with longitudinal phenotypes: performance of approximate procedures

PubMed Central

Sikorska, Karolina; Montazeri, Nahid Mostafavi; Uitterlinden, André; Rivadeneira, Fernando; Eilers, Paul HC; Lesaffre, Emmanuel

2015-01-01

Analysis of genome-wide association studies with longitudinal data using standard procedures, such as linear mixed model (LMM) fitting, leads to discouragingly long computation times. There is a need to speed up the computations significantly. In our previous work (Sikorska et al: Fast linear mixed model computations for genome-wide association studies with longitudinal data. Stat Med 2012; 32.1: 165–180), we proposed the conditional two-step (CTS) approach as a fast method providing an approximation to the P-value for the longitudinal single-nucleotide polymorphism (SNP) effect. In the first step a reduced conditional LMM is fit, omitting all the SNP terms. In the second step, the estimated random slopes are regressed on SNPs. The CTS has been applied to the bone mineral density data from the Rotterdam Study and proved to work very well even in unbalanced situations. In another article (Sikorska et al: GWAS on your notebook: fast semi-parallel linear and logistic regression for genome-wide association studies. BMC Bioinformatics 2013; 14: 166), we suggested semi-parallel computations, greatly speeding up fitting many linear regressions. Combining CTS with fast linear regression reduces the computation time from several weeks to a few minutes on a single computer. Here, we explore further the properties of the CTS both analytically and by simulations. We investigate the performance of our proposal in comparison with a related but different approach, the two-step procedure. It is analytically shown that for the balanced case, under mild assumptions, the P-value provided by the CTS is the same as from the LMM. For unbalanced data and in realistic situations, simulations show that the CTS method does not inflate the type I error rate and implies only a minimal loss of power. PMID:25712081

Cerebral Visual Impairment in Children: A Longitudinal Case Study of Functional Outcomes beyond the Visual Acuities

ERIC Educational Resources Information Center

Lam, Fook Chang; Lovett, Fiona; Dutton, Gordon N.

2010-01-01

Damage to the areas of the brain that are responsible for higher visual processing can lead to severe cerebral visual impairment (CVI). The prognosis for higher cognitive visual functions in children with CVI is not well described. We therefore present our six-year follow-up of a boy with CVI and highlight intervention approaches that have proved…

Leadership at the Top: Some Insights from a Longitudinal Case Study of a UK Business School

ERIC Educational Resources Information Center

Williams, Allan P. O.

2009-01-01

A UK business school was researched to record its history and to account for its development. The data collection and interpretation were influenced by the flexible and iterative nature of the methodology. Theories and concepts used to make sense of the findings include: open systems, force fields, and power. The focus is on strategic leadership,…

Brief Report: An Unusual Manifestation of Diagnostic Overshadowing of Pervasive Developmental Disorder--Not Otherwise Specified--A Five Year Longitudinal Case Study

ERIC Educational Resources Information Center

Meera, S. S.; Kaipa, Ramesh; Thomas, Jaslin; Shivashankar, N.

2013-01-01

Children with communication disorders present with a range of comorbid conditions. Occasionally one of the comorbid conditions manifests so strongly that the primary condition goes unnoticed by the clinician. This tendency to overlook comorbid health problems in the presence of a disability is referred to as diagnostic overshadowing. This is a…

Effectiveness of Skill-Based Substance Abuse Intervention among Male Adolescents in an Islamic Country: Case of the Islamic Republic of Iran

ERIC Educational Resources Information Center

Allahverdipour, Hamid; Bazargan, Mohsen; Farhadinasab, Abdollah; Hidarnia, Alireza; Bashirian, Saeed

2009-01-01

The prevalence of substance abuse among adolescents from low- and middle-income countries is increasing drastically and requires immediate intervention. The objective of this longitudinal quasi-experimental panel study was to design and implement a skill-based intervention to prevent and reduce substance use among urban adolescents who attended 2…

Closing the Gap: Early Childhood Education. The Achievement Gap: Early Childhood Education. Info Brief. Number 45

ERIC Educational Resources Information Center

Nelson, Anne

2006-01-01

In popular culture, the age of 40 is sometimes considered "over the hill." This is decidedly not the case for the Perry Preschoolers--a cohort of low-income, predominantly African American children who 37 years ago were randomly assigned to attend a high-quality preschool program. The latest findings from the well-known longitudinal study of this…

The Sustained Reduction of Youth Suicidal Behavior in an Urban, Multicultural School District

ERIC Educational Resources Information Center

Zenere, Frank J.; Lazarus, Philip J.

2009-01-01

An 18-year longitudinal case study of the suicide rates of students attending a large, urban, multicultural school district between 1989 and 2006 is described. The high rate of suicide (5.5 per 100,000 students ages 5-19) in the district during the period 1980-1988 led to the development and implementation of a district-wide Youth Suicide…

Implementing Comprehensive Reform of Introductory Physics at a Primarily Undergraduate Institution: A Longitudinal Case Study

ERIC Educational Resources Information Center

Rogers, Michael; Keller, Luke D .; Price, Matthew F.; Crouse, Andrew

2015-01-01

Education research provides a range of curricular reform options that can lead to improved student course outcomes. These options can appear easy to implement with the hope of immediate increases in student learning. In 2006 the Ithaca College Physics Department went down this path by moving all of their 100-level courses out of lecture halls and…

Tor: Case Study of a Boy with Autism between the Age of Three and Eight

ERIC Educational Resources Information Center

Wagner, C Reuterskiold; Nettelbladt, U.

2005-01-01

Longitudinal data are presented on a boy between the ages of three and eight. At age three he received a diagnosis of language impairment and at age six a diagnosis of high-functioning autism. Results are presented from extensive assessments at four points in time, including interviews with his mother and teachers. The results indicate that the…

A Comparison of Classroom and Online Asynchronous Problem-Based Learning for Students Undertaking Statistics Training as Part of a Public Health Masters Degree

ERIC Educational Resources Information Center

de Jong, N.; Verstegen, D. M. L.; Tan, F. E. S.; O'Connor, S. J.

2013-01-01

This case-study compared traditional, face-to-face classroom-based teaching with asynchronous online learning and teaching methods in two sets of students undertaking a problem-based learning module in the multilevel and exploratory factor analysis of longitudinal data as part of a Masters degree in Public Health at Maastricht University. Students…

A case of seropositive Neuromyelitis Optica in a paediatric patient with co-existing acute nephrotic syndrome.

PubMed

Volkman, Thomas; Hemingway, Cheryl

2017-11-01

Neuromyelitis optica (NMO) and NMO spectrum disorder (NMOSD) is a rare relapsing autoimmune disease of the central nervous system constituting less than 1% of demyelinating diseases (Jeffery and Buncic, 1996). It preferentially affects the optic nerves and spinal cord, with the brain parenchyma generally spared. Demyelinating lesions are characterised by longitudinally extensive transverse myelitis (LETM) and often longitudinally extensive optic neuritis. Following the discovery of a novel pathogenic antibody, Aquaporin 4 in 2004 (Lennon et al., 2004) this disease has been seen as a separate entity from Multiple Sclerosis (MS). We report the case of a severe AQP4 IgG case of NMO in a 10 year old child. This case unusually had a coexisting diagnosis of acute nephrotic syndrome which has only been reported once previously in the literature 2 . This article will examine some of the treatment challenges and the spectrum of co-existing autoimmune disease in NMOSD. Copyright © 2017. Published by Elsevier B.V.

Linear bunchers and half-frequency bunching method

NASA Astrophysics Data System (ADS)

Tang, J. Y.; Jiang, J. Z.; Shi, A. M.; Yin, Z. K.; Wang, Y. F.

2000-12-01

A new buncher system consisting of two bunchers has been designed and constructed for HIRFL injector cyclotron, working at the SFC acceleration modes of H=1 and H=3, respectively. The bunchers use saw-tooth RF waveform, but with double-gap drift tube electrodes and single-gap grid electrodes, respectively. The special merit of the design is introduction of the half-frequency bunching mode, utilizing half of the cyclotron RF frequency. With this method, a perfect longitudinal match between the injector SFC and the main cyclotron SSC has been reached theoretically, compared to the original efficiency of 50% for most cases. Detailed studies have been made concerning space charge effects, longitudinal dispersions through the yoke hole and the spiral inflector, and non-linearity in both the RF waveform and the stray electric field of electrodes.

Dermoscopic findings in Laugier-Hunziker syndrome.

PubMed

Gencoglan, Gulsum; Gerceker-Turk, Bengu; Kilinc-Karaarslan, Isil; Akalin, Taner; Ozdemir, Fezal

2007-05-01

Laugier-Hunziker syndrome (LHS) is a rare, acquired mucocutaneous hyperpigmentation often associated with longitudinal melanonychia. The clinical behavior of mucocutaneous pigmented lesions ranges from benign to highly malignant. Therefore, in most cases, the clinical diagnosis should be confirmed by further diagnostic methods. Dermoscopy is a noninvasive technique that has been used to make more accurate diagnoses of pigmented skin lesions. Nevertheless, to our knowledge, the dermoscopic features of the pigmented lesions in LHS have not been described previously. Herein, we report a case of LHS together with its dermoscopic features. The clinical examination revealed macular hyperpigmentation on the oral and genital mucosa, conjunctiva, and palmoplantar region together with longitudinal melanonychia. Dermoscopic examination of mucosal lesions on the patient's lips and vulva revealed a parallel pattern. Longitudinal homogeneous pigmentation was observed on the toenails. The pigmented macules on the palms and the sole showed a parallel furrow pattern. A skin biopsy sample taken from the labial lesion was compatible with a diagnosis of mucosal melanosis. By means of this case report, the dermoscopic features of the pigmented lesions in LHS are described for the first time, which facilitates diagnosis with a noninvasive technique. Future reports highlighting the dermoscopic features of this syndrome may simplify the diagnosis of LHS, which is thought to be underdiagnosed.

Poor Infants, Poor Chances: A Longitudinal Study of Progress toward Reducing Low Birth Weight and Infant Mortality in the United States and Its Largest Cities, 1979-1984.

ERIC Educational Resources Information Center

Ducey, Sara Bachman; And Others

This study examined low birth weight and infant mortality in the 50 states and the 54 largest American cities between 1979 and 1984. Its findings confirm that progress in reducing low birth weight and infant mortality has slowed, and in some cases the progress has actually reversed. Some states and many cities had higher rates of low birth weight…

Comparing identified and statistically significant lipids and polar metabolites in 15-year old serum and dried blood spot samples for longitudinal studies: Comparing lipids and metabolites in serum and DBS samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kyle, Jennifer E.; Casey, Cameron P.; Stratton, Kelly G.

The use of dried blood spots (DBS) has many advantages over traditional plasma and serum samples such as smaller blood volume required, storage at room temperature, and ability for sampling in remote locations. However, understanding the robustness of different analytes in DBS samples is essential, especially in older samples collected for longitudinal studies. Here we analyzed DBS samples collected in 2000-2001 and stored at room temperature and compared them to matched serum samples stored at -80°C to determine if they could be effectively used as specific time points in a longitudinal study following metabolic disease. Four hundred small molecules weremore » identified in both the serum and DBS samples using gas chromatograph-mass spectrometry (GC-MS), liquid chromatography-MS (LC-MS) and LC-ion mobility spectrometry-MS (LC-IMS-MS). The identified polar metabolites overlapped well between the sample types, though only one statistically significant polar metabolite in a case-control study was conserved, indicating degradation occurs in the DBS samples affecting quantitation. Differences in the lipid identifications indicated that some oxidation occurs in the DBS samples. However, thirty-six statistically significant lipids correlated in both sample types indicating that lipid quantitation was more stable across the sample types.« less

Longitudinal Treatment Outcomes of Microsurgical Treatment of Neurosensory Deficit after Lower Third Molar Surgery: A Prospective Case Series.

PubMed

Leung, Yiu Yan; Cheung, Lim Kwong

2016-01-01

To prospectively evaluate the longitudinal subjective and objective outcomes of the microsurgical treatment of lingual nerve (LN) and inferior alveolar nerve (IAN) injury after third molar surgery. A 1-year longitudinal observational study was conducted on patients who received LN or IAN repair after third molar surgery-induced nerve injury. Subjective assessments ("numbness", "hyperaesthesia", "pain", "taste disturbance", "speech" and "social life impact") and objective assessments (light touch threshold, two-point discrimination, pain threshold, and taste discrimination) were recorded. 12 patients (10 females) with 10 LN and 2 IAN repairs were recruited. The subjective outcomes at post-operative 12 months for LN and IAN repair were improved. "Pain" and "hyperaesthesia" were most drastically improved. Light touch threshold improved from 44.7 g to 1.2 g for LN repair and 2 g to 0.5 g for IAN repair. Microsurgical treatment of moderate to severe LN injury after lower third molar surgery offered significant subjective and objective sensory improvements. 100% FSR was achieved at post-operative 6 months.

The first year of practice: an investigation of the professional learning and development of promising novice physical therapists.

PubMed

Black, Lisa L; Jensen, Gail M; Mostrom, Elizabeth; Perkins, Jan; Ritzline, Pamela D; Hayward, Lorna; Blackmer, Betsy

2010-12-01

The goal in studying expertise is not merely to describe ways in which experts excel but also to understand how experts develop in order to better facilitate the development of novices. The study of novice progression helps us to understand what successful versus unsuccessful learning looks like. This understanding is critical, as autonomous practice places increased demands for advanced clinical judgments and the ability to assume professional responsibilities. The purpose of this study was to explore the experiences, learning, and development of promising novice therapists throughout their first year of practice in the United States. A longitudinal, multiple-site qualitative case study method was used for within-case and across-case analysis. A purposive sample of 11 promising new graduates from 4 physical therapist education programs participated. Investigators followed the graduates throughout their first year of practice. Data sources included: (1) semistructured interviews conducted at baseline and every 3 months thereafter for 1 year, (2) reflective journals completed at regular intervals, and (3) review of academic and clinical education records and résumés. Four themes emerged: (1) the clinical environment influenced the novice physical therapists' performance, (2) participants learned through experience and social interaction and learning was primarily directed toward self, (3) growing confidence was directly related to developing communication skills, and (4) therapists were engaged in professional identity formation and role transitions. The findings suggest there are common experiences and themes that emerge as novice physical therapists develop. Although research has been conducted on expertise in physical therapy, few longitudinal investigations have explored the development of therapists across transitions from graduate to novice to expert practitioner. This study explored and described the learning and development of graduates during their first year of practice.

The effect of a longitudinal density gradient on electron plasma wake field acceleration

NASA Astrophysics Data System (ADS)

Tsiklauri, David

2016-12-01

Three-dimensional, particle-in-cell, fully electromagnetic simulations of electron plasma wake field acceleration in the blow-out regime are presented. Earlier results are extended by (i) studying the effect of a longitudinal density gradient, (ii) avoiding the use of a co-moving simulation box, (iii) inclusion of ion motion, and (iv) studying fully electromagnetic plasma wake fields. It is established that injecting driving and trailing electron bunches into a positive density gradient of 10-fold increasing density over 10 cm long lithium vapour plasma results in spatially more compact and three times larger, compared with the uniform density case, electric fields (-6.4×1010 V m-1), leading to acceleration of the trailing bunch up to 24.4 GeV (starting from an initial 20.4 GeV), with energy transfer efficiencies from the leading to trailing bunch of 75%. In the uniform density case, a -2.5×1010 V m-1 wake is created leading to acceleration of the trailing bunch up to 22.4 GeV, with energy transfer efficiencies of 65%. It is also established that injecting the electron bunches into a negative density gradient of 10-fold decreasing density over 10 cm long plasma results in spatially more spread and two and a half smaller electric fields (-1.0×1010 V m-1), leading to a weaker acceleration of the trailing bunch up to 21.4 GeV, with energy transfer efficiencies of 45%. Taking ion motions into consideration shows that in the plasma wake ion number density can increase over a few times the background value. It is also shown that transverse electromagnetic fields in a plasma wake are of the same order as the longitudinal (electrostatic) ones.

A longitudinal study of neuromelanin-sensitive magnetic resonance imaging in Parkinson's disease.

PubMed

Matsuura, Keita; Maeda, Masayuki; Tabei, Ken-Ichi; Umino, Maki; Kajikawa, Hiroyuki; Satoh, Masayuki; Kida, Hirotaka; Tomimoto, Hidekazu

2016-10-28

Neuromelanin-sensitive MR imaging (NMI) is an increasingly powerful tool for the diagnosis of Parkinson's disease (PD). This study was undertaken to evaluate longitudinal changes on NMI in PD patients. We examined longitudinal changes on NMI in 14 PD patients. The area and contrast ratio (CR) of the substantia nigra pars compacta (SNc) were comparatively analyzed. The total area and CR of the SNc upon follow-up NMI were significantly smaller than those on initial NMI (from 33.5±18.9 pixels and 6.35±2.86% to 21.5±16.7 pixels and 4.19±2.11%; Wilcoxon signed-rank test, p<0.001 and p=0.022, respectively). The area and CR of the dominant side SNc upon initial NMI were significantly greater than those on follow-up NMI (from 15.3±9.1 pixels and 6.5±2.7% to 7.9±8.5 pixels and 3.7±2.9%; Wilcoxon signed-rank test, p=0.002 and p=0.007, respectively). On a case-by-case basis, the area of the SNc invariably decreased upon follow-up NMI in all patients. We further demonstrated that the total area and CR of the SNc negatively correlated with disease duration (Pearson correlation coefficient, r=-0.63, p<0.001 and r=-0.41, p=0.031, respectively). In area analyses, our results demonstrated very high intraclass correlation coefficients for both intra- and inter-rater reliability. NMI is a useful and reliable tool for detecting neuropathological changes over time in PD patients. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Human fascioliasis in South Africa.

PubMed

Black, J; Ntusi, N; Stead, P; Mayosi, B; Mendelson, M

2013-07-29

Human fascioliasis has the widest latitudinal, longitudinal and altitudinal distribution of any vector-borne disease, yet only 3 cases have been reported from South Africa, the last in 1964. We report 2 cases from the same geographic area associated with local consumption of watercress, suggesting an endemic focus. 

Delusion of inanimate doubles: description of a case of focal retrograde amnesia.

PubMed

Abbate, Carlo; Trimarchi, Pietro Davide; Salvi, Gian Pietro; Quarenghi, Anna Maria; Vergani, Carlo; Luzzatti, Claudio

2012-01-01

This paper reports the case of a patient, M.P., who developed delusion of inanimate doubles, without Capgras syndrome, after traumatic brain injury. His delusional symptoms were studied longitudinally and the cognitive impairments associated with delusion were investigated. Data suggest that M.P. did 'perceive' the actual differences between doubles and originals rather than 'confabulate' them. The cognitive profile, characterized by retrograde episodic amnesia, but neither object processing impairment nor confabulations, supports this hypothesis. The study examines the nature of object misidentification based on Ellis' and Staton's account and proposes a new account based on concurrent unbiased retrieval of semantic memory traces and biased recollection of episodic memory traces.

OCD and transvestism: is there a relationship?

PubMed

Abdo, C H; Hounie, A; de Tubino Scanavino, M; Miguel, E C

2001-06-01

There have been reports of obsessive-compulsive disorder (OCD) patients with comorbid paraphilias. In this paper, two cases of comorbidity between OCD and transvestism are reported with the aim of discussing possible explanations for this association. Longitudinal case studies of two patients with OCD and tranvestism according to the DSM-IV were assessed using semi-structured interviews. Both patients presented with OCD and comorbid transvestism with different clinical features and treatment response. The case whose cross-dressing was more egodystonic responded better to treatment. It is possible that some cases of transvestism are OCD-related while others are more related to a gender identity disorder. A dimensional approach focusing on common phenomenological and neurobiological substrates is suggested as particularly useful for clinical management and future research of both disorders.

Dysmobility syndrome: current perspectives.

PubMed

Hill, Keith D; Farrier, Kaela; Russell, Melissa; Burton, Elissa

2017-01-01

A new term, dysmobility syndrome, has recently been described as a new approach to identify older people at risk of poor health outcomes. The aim was to undertake a systematic review of the existing research literature on dysmobility syndrome. All articles reporting dysmobility syndrome were identified in a systematic review of Medline (Proquest), CINAHL, PubMed, PsycInfo, EMBASE, and Scopus databases. Key characteristics of identified studies were extracted and summarized. The systematic review identified five papers (three cross-sectional, one case control, and one longitudinal study). No intervention studies were identified. Prevalence of dysmobility syndrome varied between studies (22%-34% in three of the studies). Dysmobility syndrome was shown to be associated with reduced function, increased falls and fractures, and a longitudinal study showed its significant association with mortality. Early research on dysmobility syndrome indicates that it may be a useful classification approach to identify older people at risk of adverse health outcomes and to target for early interventions. Future research needs to standardize the optimal mix of measures and cut points, and investigate whether balance performance may be a more useful factor than history of falls for dysmobility syndrome.