The impact of a multidisciplinary self-care management program on quality of life, self-care, adherence to anti-hypertensive therapy, glycemic control, and renal function in diabetic kidney disease: A Cross-over Study Protocol.

PubMed

Helou, Nancy; Talhouedec, Dominique; Shaha, Maya; Zanchi, Anne

2016-07-19

Diabetic kidney disease, a global health issue, remains associated with high morbidity and mortality. Previous research has shown that multidisciplinary management of chronic disease can improve patient outcomes. The effect of multidisciplinary self-care management on quality of life and renal function of patients with diabetic kidney disease has not yet been well established. The aim of this study is to evaluate the impact of a multidisciplinary self-care management program on quality of life, self-care behavior, adherence to anti-hypertensive treatment, glycemic control, and renal function of adults with diabetic kidney disease. A uniform balanced cross-over design is used, with the objective to recruit 40 adult participants with diabetic kidney disease, from public and private out-patient settings in French speaking Switzerland. Participants are randomized in equal number into four study arms. Each participant receives usual care alternating with the multidisciplinary self- care management program. Each treatment period lasts three months and is repeated twice at different time intervals over 12 months depending on the cross-over arm. The multidisciplinary self-care management program is led by an advanced practice nurse and adds nursing and dietary consultations and follow-ups, to the habitual management provided by the general practitioner, the nephrologist and the diabetologist. Data is collected every three months for 12 months. Quality of life is measured using the Audit of Diabetes-Dependent Quality of Life scale, patient self-care behavior is assessed using the Revised Summary of Diabetes Self-Care Activities, and adherence to anti-hypertensive therapy is evaluated using the Medication Events Monitoring System. Blood glucose control is measured by the glycated hemoglobin levels and renal function by serum creatinine, estimated glomerular filtration rate and urinary albumin/creatinine ratio. Data will be analyzed using STATA version 14. The cross-over design will elucidate the responses of individual participant to each treatment, and will allow us to better evaluate the use of such a design in clinical settings and behavioral studies. This study also explores the impact of a theory-based nursing practice and its implementation into a multidisciplinary context. ClinicalTrials.gov identifier: NCT01967901 , registered on the 18th of October 2013.

The influence of traffic signal solutions on self-reported road-crossing behavior.

PubMed

Di Stasi, Leandro L; Megías, Alberto; Cándido, Antonio; Maldonado, Antonio; Catena, Andrés

2015-01-07

Injury to pedestrians is a major safety hazard in many countries. Since the beginning of the last century, modern cities have been designed around the use of motor vehicles despite the unfavourable interactions between the vehicles and pedestrians. This push towards urbanization resulted in a substantial number of crashes and fatalities involving pedestrians every day, all over the world. Thus, improving the design of urban cities and townships is a pressing issue for modern society. The study presented here provides a characterization of pedestrian safety problems, with the emphasis on signalized crosswalks (i.e. traffic signal) design solutions. We tested the impact of seven different traffic light configurations (steady [green, yellow, and red], flashing [green, yellow, and red], and light off) on pedestrian self-reported road-crossing behavior, using a 11-point scale -ranging from 0 ("I never cross in this situation") to 10 ("I always cross in this situation"). Results showed that mandatory solutions (steady green vs. steady red) are the best solutions to avoid unsafe pedestrian behaviors while crossing controlled intersections (frequency of crossing: Mgreen = 9.4 ± 1 vs. Mred = 2.6 ± 2). These findings offer important guidelines for the design of future traffic signals for encouraging a pedestrian/transit-friendly environment.

A Comparison of Structurally Connected and Multiple Spacecraft Interferometers

NASA Technical Reports Server (NTRS)

Surka, Derek M.; Crawley, Edward F.

1996-01-01

Structurally connected and multiple spacecraft interferometers are compared in an attempt to establish the maximum baseline (referred to as the "cross-over baseline") for which it is preferable to operate a single-structure interferometer in space rather than an interferometer composed of numerous, smaller spacecraft. This comparison is made using the total launched mass of each configuration as the comparison metric. A framework of study within which structurally connected and multiple spacecraft interferometers can be compared is presented in block diagram form. This methodology is then applied to twenty-two different combinations of trade space parameters to investigate the effects of different orbits, orientations, truss materials, propellants, attitude control actuators, onboard disturbance sources, and performance requirements on the cross-over baseline. Rotating interferometers and the potential advantages of adding active structural control to the connected truss of the structurally connected interferometer are also examined. The minimum mass design of the structurally connected interferometer that meets all performance-requirements and satisfies all imposed constraints is determined as a function of baseline. This minimum mass design is then compared to the design of the multiple spacecraft interferometer. It is discovered that the design of the minimum mass structurally connected interferometer that meets all performance requirements and constraints in solar orbit is limited by the minimum allowable aspect ratio, areal density, and gage of the struts. In the formulation of the problem used in this study, there is no advantage to adding active structural control to the truss for interferometers in solar orbit. The cross-over baseline for missions of practical duration (ranging from one week to thirty years) in solar orbit is approximately 400 m for non-rotating interferometers and 650 m for rotating interferometers.

Bibliometric analysis of scientific articles published in Brazilian and international orthodontic journals over a 10-year period.

PubMed

Primo, Neudí Antonio; Gazzola, Vivian Bertoglio; Primo, Bruno Tochetto; Tovo, Maximiano Ferreira; Faraco, Italo Medeiros

2014-01-01

This study aimed at describing the profiles of Brazilian and international studies published in orthodontic journals. The sample comprised 635 articles selected from two scientific journals, i.e., Dental Press Journal of Orthodontics and American Journal of Orthodontics and Dentofacial Orthopedics, which were analyzed at three different intervals over a 10-year period (1999 - 2004 - 2009). Articles were described in terms of knowledge domain, study design, and country of origin (or state of origin for Brazilian papers). The most frequent study designs adopted in international studies were cohort (23.9%) and cross-sectional (21.7%) designs. Among Brazilian papers, cross-sectional studies (28.9%) and literature reviews (24.6%) showed greater frequency. The topics most often investigated in international articles were dental materials (17%) and treatment devices (12.4%), with the latter topic being addressed by 16% of the Brazilian publications, followed by malocclusion, with 12.6%. In all cases, the most frequent countries of origin coincided with the countries of origin of each journal. The majority of the studies analyzed featured a low level of scientific evidence. Moreover, the findings showed that journals tend to publish studies produced in their own country of origin, and that there are marked discrepancies in the number of papers published by different Brazilian states.

The improved electrochemical performance of cross-linked 3D graphene nanoribbon monolith electrodes

NASA Astrophysics Data System (ADS)

Vineesh, Thazhe Veettil; Alwarappan, Subbiah; Narayanan, Tharangattu N.

2015-04-01

Technical advancement in the field of ultra-small sensors and devices demands the development of novel micro- or nano-based architectures. Here we report the design and assembly of cross-linked three dimensional graphene nanoribbons (3D GNRs) using solution based covalent binding of individual 2D GNRs and demonstrate its electrochemical application as a 3D electrode. The enhanced performance of 3D GNRs over individual 2D GNRs is established using standard redox probes - [Ru(NH3)6]3+/2+, [Fe(CN)6]3-/4- and important bio-analytes - dopamine and ascorbic acid. 3D GNRs are found to have high double layer capacitance (2482 μF cm-2) and faster electron transfer kinetics; their exceptional electrocatalytic activity towards the oxygen reduction reaction is indicative of their potential over a wide range of electrochemical applications. Moreover, this study opens a new platform for the design of novel point-of-care devices and electrodes for energy devices.Technical advancement in the field of ultra-small sensors and devices demands the development of novel micro- or nano-based architectures. Here we report the design and assembly of cross-linked three dimensional graphene nanoribbons (3D GNRs) using solution based covalent binding of individual 2D GNRs and demonstrate its electrochemical application as a 3D electrode. The enhanced performance of 3D GNRs over individual 2D GNRs is established using standard redox probes - [Ru(NH3)6]3+/2+, [Fe(CN)6]3-/4- and important bio-analytes - dopamine and ascorbic acid. 3D GNRs are found to have high double layer capacitance (2482 μF cm-2) and faster electron transfer kinetics; their exceptional electrocatalytic activity towards the oxygen reduction reaction is indicative of their potential over a wide range of electrochemical applications. Moreover, this study opens a new platform for the design of novel point-of-care devices and electrodes for energy devices. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr07315k

Teachers' Attitudes toward Technology Integration in Schools: A Four-Year Study

ERIC Educational Resources Information Center

Liu, Yuliang; Szabo, Zsuzsanna

2009-01-01

This trend study was designed to examine a current trend and pattern, as well as a development of teachers' concerns about technology integration in the curriculum. The study was conducted by repeated cross-sectional studies, applying the same research instrument to different samples of subjects at different points, over a period of four years…

Effect of fescue toxicosis on whole body energy and nitrogen balance, in situ degradation and ruminal passage rates in Holstein steers

USDA-ARS?s Scientific Manuscript database

This study was designed to examine alteration of ruminal kinetics, as well as N and energy balance during fescue toxicosis. Six ruminally cannulated Holstein steers (BW=217 ±7 kg) were weight-matched into pairs and pair-fed throughout a cross-over design experiment with a 2x2 factorial treatment str...

Intravenous volume tomographic pulmonary angiography imaging

NASA Astrophysics Data System (ADS)

Ning, Ruola; Strang, John G.; Chen, Biao; Conover, David L.; Yu, Rongfeng

1999-05-01

This study presents a new intravenous (IV) tomographic angiography imaging technique, called intravenous volume tomographic digital angiography (VTDA) for cross sectional pulmonary angiography. While the advantages of IV-VTDA over spiral CT in terms of volume scanning time and resolution have been validated and reported in our previous papers for head and neck vascular imaging, the superiority of IV-VTDA over spiral CT for cross sectional pulmonary angiography has not been explored yet. The purpose of this study is to demonstrate the advantage of isotropic resolution of IV-VTDA in the x, y and z directions through phantom and animal studies, and to explore its clinical application for detecting clots in pulmonary angiography. A prototype image intensifier-based VTDA imaging system has been designed and constructed by modifying a GE 8800 CT scanner. This system was used for a series of phantom and dog studies. A pulmonary vascular phantom was designed and constructed. The phantom was scanned using the prototype VTDA system for direct 3D reconstruction. Then the same phantom was scanned using a GE CT/i spiral CT scanner using the routine pulmonary CT angiography protocols. IV contrast injection and volume scanning protocols were developed during the dog studies. Both VTDA reconstructed images and spiral CT images of the specially designed phantom were analyzed and compared. The detectability of simulated vessels and clots was assessed as the function of iodine concentration levels, oriented angles, and diameters of the vessels and clots. A set of 3D VTDA reconstruction images of dog pulmonary arteries was obtained with different IV injection rates and isotropic resolution in the x, y and z directions. The results of clot detection studies in dog pulmonary arteries have also been shown. This study presents a new tomographic IV angiography imaging technique for cross sectional pulmonary angiography. The results of phantom and animal studies indicate that IV-VTDA is superior to spiral CT for cross sectional pulmonary angiography.

Young Children's Conceptions of Science and Scientists

ERIC Educational Resources Information Center

Lee, Tiffany R.

2010-01-01

This study explores young children's images of science and scientists, their sources for scientific knowledge, and the nature of their science-related experiences. A cross-sectional design was used to study how students' ideas differ over the first three years of elementary school. A modified version of the Draw-a-Scientist Test (DAST) and a…

Longitudinal Study of Nightmares in Children: Stability and Effect of Emotional Symptoms

ERIC Educational Resources Information Center

Schredl, Michael; Fricke-Oerkermann, Leonie; Mitschke, Alexander; Wiater, Alfred; Lehmkuhl, Gerd

2009-01-01

Nightmares are defined as dreams with strong negative emotions which awaken the dreamer and are common during childhood: cross-sectional data shows the highest prevalence rates between the ages of five and ten. The present longitudinal study was designed to study the stability of nightmares over the course of 2 years. Sleep questionnaires and…

Supervised Home Training of Dialogue Skills in Chronic Aphasia: A Randomized Parallel Group Study

ERIC Educational Resources Information Center

Nobis-Bosch, Ruth; Springer, Luise; Radermacher, Irmgard; Huber, Walter

2011-01-01

Purpose: The aim of this study was to prove the efficacy of supervised self-training for individuals with aphasia. Linguistic and communicative performance in structured dialogues represented the main study parameters. Method: In a cross-over design for randomized matched pairs, 18 individuals with chronic aphasia were examined during 12 weeks of…

A two wave cross-lagged study of work-role conflict, work-family conflict and emotional exhaustion.

PubMed

Jensen, Maria Therese

2016-12-01

By using a two-wave panel design, the present study aimed to study causal, reversed, and reciprocal relations among work-role conflict, work-family conflict, and emotional exhaustion. The Conservation of Resources theory was applied as a theoretical framework. The study was conducted in a large Norwegian oil and gas company (n = 1703). The results demonstrated positive cross-lagged effects of work-role conflict and work-family conflict on emotional exhaustion. In addition, emotional exhaustion predicted work-family conflict over time, and work-family conflict predicted work-role conflict over time, indicating the presence of reciprocal effects. The current study adds new knowledge to the positioning of work-family conflict in relation to perceived conflict in the workplace and emotional exhaustion. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Cross-Layer Adaptive Feedback Scheduling of Wireless Control Systems

PubMed Central

Xia, Feng; Ma, Longhua; Peng, Chen; Sun, Youxian; Dong, Jinxiang

2008-01-01

There is a trend towards using wireless technologies in networked control systems. However, the adverse properties of the radio channels make it difficult to design and implement control systems in wireless environments. To attack the uncertainty in available communication resources in wireless control systems closed over WLAN, a cross-layer adaptive feedback scheduling (CLAFS) scheme is developed, which takes advantage of the co-design of control and wireless communications. By exploiting cross-layer design, CLAFS adjusts the sampling periods of control systems at the application layer based on information about deadline miss ratio and transmission rate from the physical layer. Within the framework of feedback scheduling, the control performance is maximized through controlling the deadline miss ratio. Key design parameters of the feedback scheduler are adapted to dynamic changes in the channel condition. An event-driven invocation mechanism for the feedback scheduler is also developed. Simulation results show that the proposed approach is efficient in dealing with channel capacity variations and noise interference, thus providing an enabling technology for control over WLAN. PMID:27879934

Bibliometric analysis of scientific articles published in Brazilian and international orthodontic journals over a 10-year period

PubMed Central

Primo, Neudí Antonio; Gazzola, Vivian Bertoglio; Primo, Bruno Tochetto; Tovo, Maximiano Ferreira; Faraco Junior, Italo Medeiros

2014-01-01

Objective This study aimed at describing the profiles of Brazilian and international studies published in orthodontic journals. Methods The sample comprised 635 articles selected from two scientific journals, i.e., Dental Press Journal of Orthodontics and American Journal of Orthodontics and Dentofacial Orthopedics, which were analyzed at three different intervals over a 10-year period (1999 - 2004 - 2009). Articles were described in terms of knowledge domain, study design, and country of origin (or state of origin for Brazilian papers). Results The most frequent study designs adopted in international studies were cohort (23.9%) and cross-sectional (21.7%) designs. Among Brazilian papers, cross-sectional studies (28.9%) and literature reviews (24.6%) showed greater frequency. The topics most often investigated were dental materials (17%) and treatment devices (12.4%) in international articles, with the latter topic being addressed by 16% of the Brazilian publications, followed by malocclusion, with 12.6%. In all cases, the most frequent countries of origin coincided with the countries of origin of each journal. Conclusions The majority of the studies analyzed featured a low level of scientific evidence. Moreover, the findings showed that journals tend to publish studies produced in their own country of origin, and that there are marked discrepancies in the number of papers published by different Brazilian states. PMID:24945515

Genomic Prediction of Single Crosses in the Early Stages of a Maize Hybrid Breeding Pipeline.

PubMed

Kadam, Dnyaneshwar C; Potts, Sarah M; Bohn, Martin O; Lipka, Alexander E; Lorenz, Aaron J

2016-09-19

Prediction of single-cross performance has been a major goal of plant breeders since the beginning of hybrid breeding. Recently, genomic prediction has shown to be a promising approach, but only limited studies have examined the accuracy of predicting single-cross performance. Moreover, no studies have examined the potential of predicting single crosses among random inbreds derived from a series of biparental families, which resembles the structure of germplasm comprising the initial stages of a hybrid maize breeding pipeline. The main objectives of this study were to evaluate the potential of genomic prediction for identifying superior single crosses early in the hybrid breeding pipeline and optimize its application. To accomplish these objectives, we designed and analyzed a novel population of single crosses representing the Iowa Stiff Stalk Synthetic/Non-Stiff Stalk heterotic pattern commonly used in the development of North American commercial maize hybrids. The performance of single crosses was predicted using parental combining ability and covariance among single crosses. Prediction accuracies were estimated using cross-validation and ranged from 0.28 to 0.77 for grain yield, 0.53 to 0.91 for plant height, and 0.49 to 0.94 for staygreen, depending on the number of tested parents of the single cross and genomic prediction method used. The genomic estimated general and specific combining abilities showed an advantage over genomic covariances among single crosses when one or both parents of the single cross were untested. Overall, our results suggest that genomic prediction of single crosses in the early stages of a hybrid breeding pipeline holds great potential to re-design hybrid breeding and increase its efficiency. Copyright © 2016 Author et al.

A Bayesian approach to the statistical analysis of device preference studies.

PubMed

Fu, Haoda; Qu, Yongming; Zhu, Baojin; Huster, William

2012-01-01

Drug delivery devices are required to have excellent technical specifications to deliver drugs accurately, and in addition, the devices should provide a satisfactory experience to patients because this can have a direct effect on drug compliance. To compare patients' experience with two devices, cross-over studies with patient-reported outcomes (PRO) as response variables are often used. Because of the strength of cross-over designs, each subject can directly compare the two devices by using the PRO variables, and variables indicating preference (preferring A, preferring B, or no preference) can be easily derived. Traditionally, methods based on frequentist statistics can be used to analyze such preference data, but there are some limitations for the frequentist methods. Recently, Bayesian methods are considered an acceptable method by the US Food and Drug Administration to design and analyze device studies. In this paper, we propose a Bayesian statistical method to analyze the data from preference trials. We demonstrate that the new Bayesian estimator enjoys some optimal properties versus the frequentist estimator. Copyright © 2012 John Wiley & Sons, Ltd.

Sample size calculations for stepped wedge and cluster randomised trials: a unified approach

PubMed Central

Hemming, Karla; Taljaard, Monica

2016-01-01

Objectives To clarify and illustrate sample size calculations for the cross-sectional stepped wedge cluster randomized trial (SW-CRT) and to present a simple approach for comparing the efficiencies of competing designs within a unified framework. Study Design and Setting We summarize design effects for the SW-CRT, the parallel cluster randomized trial (CRT), and the parallel cluster randomized trial with before and after observations (CRT-BA), assuming cross-sectional samples are selected over time. We present new formulas that enable trialists to determine the required cluster size for a given number of clusters. We illustrate by example how to implement the presented design effects and give practical guidance on the design of stepped wedge studies. Results For a fixed total cluster size, the choice of study design that provides the greatest power depends on the intracluster correlation coefficient (ICC) and the cluster size. When the ICC is small, the CRT tends to be more efficient; when the ICC is large, the SW-CRT tends to be more efficient and can serve as an alternative design when the CRT is an infeasible design. Conclusion Our unified approach allows trialists to easily compare the efficiencies of three competing designs to inform the decision about the most efficient design in a given scenario. PMID:26344808

Research design and statistical methods in Pakistan Journal of Medical Sciences (PJMS).

PubMed

Akhtar, Sohail; Shah, Syed Wadood Ali; Rafiq, M; Khan, Ajmal

2016-01-01

This article compares the study design and statistical methods used in 2005, 2010 and 2015 of Pakistan Journal of Medical Sciences (PJMS). Only original articles of PJMS were considered for the analysis. The articles were carefully reviewed for statistical methods and designs, and then recorded accordingly. The frequency of each statistical method and research design was estimated and compared with previous years. A total of 429 articles were evaluated (n=74 in 2005, n=179 in 2010, n=176 in 2015) in which 171 (40%) were cross-sectional and 116 (27%) were prospective study designs. A verity of statistical methods were found in the analysis. The most frequent methods include: descriptive statistics (n=315, 73.4%), chi-square/Fisher's exact tests (n=205, 47.8%) and student t-test (n=186, 43.4%). There was a significant increase in the use of statistical methods over time period: t-test, chi-square/Fisher's exact test, logistic regression, epidemiological statistics, and non-parametric tests. This study shows that a diverse variety of statistical methods have been used in the research articles of PJMS and frequency improved from 2005 to 2015. However, descriptive statistics was the most frequent method of statistical analysis in the published articles while cross-sectional study design was common study design.

Comparison of the inhibitory effects of cilostazol, acetylsalicylic acid and ticlopidine on platelet functions ex vivo. Randomized, double-blind cross-over study.

PubMed

Ikeda, Y; Kikuchi, M; Murakami, H; Satoh, K; Murata, M; Watanabe, K; Ando, Y

1987-05-01

A randomized double-blind cross-over study was conducted to determine the inhibitory effects of acetylsalicylic acid (ASA), ticlopidine (TP) and cilostazol (OPC-13013; in the following briefly called CS), a new antithrombotic agent on platelet functions ex vivo. Nine patients with cerebral thrombosis were enrolled in this study. Patients were given each of the three drugs for one week in a complete cross-over design according to a randomization schedule, followed by a wash-out period with a placebo for one week. It was found that CS and TP significantly inhibited platelet aggregation induced by ADP. Collagen- and arachidonic acid-induced platelet aggregation was all inhibited by CS, TP and ASA. Duncan's multiple range test to compare the anti-platelet effects of the three drugs revealed that: CS greater than ASA and TP greater than ASA in inhibiting ADP-induced platelet aggregation and CS greater than TP and ASA greater than TP in inhibiting arachidonic acid-induced platelet aggregation. These results may suggest that CS is superior to ASA and TP in inhibiting platelet aggregation ex vivo.

A State Space Modeling Approach to Mediation Analysis

ERIC Educational Resources Information Center

Gu, Fei; Preacher, Kristopher J.; Ferrer, Emilio

2014-01-01

Mediation is a causal process that evolves over time. Thus, a study of mediation requires data collected throughout the process. However, most applications of mediation analysis use cross-sectional rather than longitudinal data. Another implicit assumption commonly made in longitudinal designs for mediation analysis is that the same mediation…

Reciprocal Influences between Parents' Marital Problems and Adolescent Internalizing and Externalizing Behavior

ERIC Educational Resources Information Center

Cui, Ming; Donnellan, M. Brent; Conger, Rand D.

2007-01-01

The present study examines reciprocal associations between marital functioning and adolescent maladjustment using cross-lagged autoregressive models. The research involved 451 early adolescents and their families and used a prospective, longitudinal research design with multi-informant methods. Results indicate that parental conflicts over child…

Canada Youth & AIDS Study.

ERIC Educational Resources Information Center

King, Alan J. C.; And Others

This report contains the findings from a survey of over 38,000 youth in grades 7, 9, 11, and the first year of college or university, designed to obtain a cross-sectional perspective of the development of knowledge, attitudes, and behaviors related to Acquired Immune Deficiency Syndrome and other sexually transmitted diseases (STDs). Also included…

The Lifeways Cross-Generation Study: design, recruitment and data management considerations.

PubMed

O'Mahony, D; Fallon, U B; Hannon, F; Kloeckner, K; Avalos, G; Murphy, A W; Kelleher, C C

2007-09-01

The Lifeways Cross-Generation Cohort Study was first established in 2001 and is a unique longitudinal database in Ireland, with currently over three and a half thousand family participants derived from 1124 mothers recruited initially during pregnancy, mainly during 2002. The database comprises a) baseline self-reported health data for all mothers, a third of fathers and at least one grandparent b) clinical hospital data at recruitment, c) three year follow-up data from the families' General Practitioners, and d) linkage to hospital and vaccination databases. Data collection for the five-year follow-up with parents is underway, continuing through 2007. Because there is at present no single national/regional health information system in Ireland, original data instruments were designed to capture data directly from family members and through their hospitals and healthcare providers. A system of relational databases was designed to coordinate data capture for a complex array of study instruments and to facilitate tracking of family members at different time points.

The Moral Competence Test: An Examination of Validity for Samples in the United States

ERIC Educational Resources Information Center

Biggs, Donald A.; Colesante, Robert J.

2015-01-01

The Moral Competence Test (MCT) was designed over 30 years ago to provide a resource for educators interested in conducting cross-cultural studies of moral development and education. Since its origin, it has been translated into at least 30 languages and used in hundreds of studies. However, few studies provide evidence to support the use of the…

What Alumni Value from New Product Development Education: A Longitudinal Study

ERIC Educational Resources Information Center

Cobb, Corie L.; Hey, Jonathan; Agogino, Alice M.; Beckman, Sara L.; Kim, Sohyeong

2016-01-01

We present a longitudinal study of what graduates take away from a cross-disciplinary graduate-level New Product Development (NPD) course at UC Berkeley over a 15-year period from 1996-2010. We designed and deployed a longitudinal survey and interviewed a segment of our NPD alumni population to better understand how well our course prepared these…

Training Verbal and Nonverbal Communication Interview Skills to Adolescents

ERIC Educational Resources Information Center

Olszewski, Abbie; Panorska, Anna; Gillam, Sandra Laing

2017-01-01

Adolescents' verbal and nonverbal communication skills were compared before and after training in a workforce readiness training program, Language for Scholars (LFS), and a study skills program, Ideal Student Workshop (ISW). A cross-over design was used, ensuring that 44 adolescents received both programs and acted as their own control. The LFS…

Changes in Adult Child Caregiver Networks

ERIC Educational Resources Information Center

Szinovacz, Maximiliane E.; Davey, Adam

2007-01-01

Purpose: Caregiving research has typically relied on cross-sectional data that focus on the primary caregiver. This approach neglects the dynamic and systemic character of caregiver networks. Our analyses addressed changes in adult child care networks over a 2-year period. Design and Methods: The study relied on pooled data from Waves 1 through 5…

Augmented Cross-Sectional Studies with Abbreviated Follow-up for Estimating HIV Incidence

PubMed Central

Claggett, B.; Lagakos, S.W.; Wang, R.

2011-01-01

Summary Cross-sectional HIV incidence estimation based on a sensitive and less-sensitive test offers great advantages over the traditional cohort study. However, its use has been limited due to concerns about the false negative rate of the less-sensitive test, reflecting the phenomenon that some subjects may remain negative permanently on the less-sensitive test. Wang and Lagakos (2010) propose an augmented cross-sectional design which provides one way to estimate the size of the infected population who remain negative permanently and subsequently incorporate this information in the cross-sectional incidence estimator. In an augmented cross-sectional study, subjects who test negative on the less-sensitive test in the cross-sectional survey are followed forward for transition into the nonrecent state, at which time they would test positive on the less-sensitive test. However, considerable uncertainty exists regarding the appropriate length of follow-up and the size of the infected population who remain nonreactive permanently to the less-sensitive test. In this paper, we assess the impact of varying follow-up time on the resulting incidence estimators from an augmented cross-sectional study, evaluate the robustness of cross-sectional estimators to assumptions about the existence and the size of the subpopulation who will remain negative permanently, and propose a new estimator based on abbreviated follow-up time (AF). Compared to the original estimator from an augmented cross-sectional study, the AF Estimator allows shorter follow-up time and does not require estimation of the mean window period, defined as the average time between detectability of HIV infection with the sensitive and less-sensitive tests. It is shown to perform well in a wide range of settings. We discuss when the AF Estimator would be expected to perform well and offer design considerations for an augmented cross-sectional study with abbreviated follow-up. PMID:21668904

Augmented cross-sectional studies with abbreviated follow-up for estimating HIV incidence.

PubMed

Claggett, B; Lagakos, S W; Wang, R

2012-03-01

Cross-sectional HIV incidence estimation based on a sensitive and less-sensitive test offers great advantages over the traditional cohort study. However, its use has been limited due to concerns about the false negative rate of the less-sensitive test, reflecting the phenomenon that some subjects may remain negative permanently on the less-sensitive test. Wang and Lagakos (2010, Biometrics 66, 864-874) propose an augmented cross-sectional design that provides one way to estimate the size of the infected population who remain negative permanently and subsequently incorporate this information in the cross-sectional incidence estimator. In an augmented cross-sectional study, subjects who test negative on the less-sensitive test in the cross-sectional survey are followed forward for transition into the nonrecent state, at which time they would test positive on the less-sensitive test. However, considerable uncertainty exists regarding the appropriate length of follow-up and the size of the infected population who remain nonreactive permanently to the less-sensitive test. In this article, we assess the impact of varying follow-up time on the resulting incidence estimators from an augmented cross-sectional study, evaluate the robustness of cross-sectional estimators to assumptions about the existence and the size of the subpopulation who will remain negative permanently, and propose a new estimator based on abbreviated follow-up time (AF). Compared to the original estimator from an augmented cross-sectional study, the AF estimator allows shorter follow-up time and does not require estimation of the mean window period, defined as the average time between detectability of HIV infection with the sensitive and less-sensitive tests. It is shown to perform well in a wide range of settings. We discuss when the AF estimator would be expected to perform well and offer design considerations for an augmented cross-sectional study with abbreviated follow-up. © 2011, The International Biometric Society.

Building Networks for Global Clinical Research: The Basics.

PubMed

Shearer, David W; Volberding, Paul A; Schemitsch, Emil H; Cook, Gillian E; Slobogean, Gerard P; Morshed, Saam

2015-12-01

Over the last several decades, interest in global health across all fields of medicine, including orthopaedic surgery, has grown markedly. Cross-national collaborations are an effective means of conducting high-quality clinical research and offer many advantages over single-center investigations. Successful collaboration requires a well-designed research protocol, development of an effective team structure, and the funding to ensure the project is sustained to completion. Equally important, investigators must consider the social, linguistic, and cultural context in which the study is being undertaken. Although randomized clinical trials are the highest level of evidence, study designs may have to be adapted to accommodate available resources, expertise, and local contextual factors. With appropriate planning, these collaborative endeavors can generate changes in clinical practice and positively impact health policy.

Research design and statistical methods in Pakistan Journal of Medical Sciences (PJMS)

PubMed Central

Akhtar, Sohail; Shah, Syed Wadood Ali; Rafiq, M.; Khan, Ajmal

2016-01-01

Objective: This article compares the study design and statistical methods used in 2005, 2010 and 2015 of Pakistan Journal of Medical Sciences (PJMS). Methods: Only original articles of PJMS were considered for the analysis. The articles were carefully reviewed for statistical methods and designs, and then recorded accordingly. The frequency of each statistical method and research design was estimated and compared with previous years. Results: A total of 429 articles were evaluated (n=74 in 2005, n=179 in 2010, n=176 in 2015) in which 171 (40%) were cross-sectional and 116 (27%) were prospective study designs. A verity of statistical methods were found in the analysis. The most frequent methods include: descriptive statistics (n=315, 73.4%), chi-square/Fisher’s exact tests (n=205, 47.8%) and student t-test (n=186, 43.4%). There was a significant increase in the use of statistical methods over time period: t-test, chi-square/Fisher’s exact test, logistic regression, epidemiological statistics, and non-parametric tests. Conclusion: This study shows that a diverse variety of statistical methods have been used in the research articles of PJMS and frequency improved from 2005 to 2015. However, descriptive statistics was the most frequent method of statistical analysis in the published articles while cross-sectional study design was common study design. PMID:27022365

Photonic-crystal diplexers for terahertz-wave applications.

PubMed

Yata, Masahiro; Fujita, Masayuki; Nagatsuma, Tadao

2016-04-04

A compact diplexer is designed using a silicon photonic-crystal directional coupler of length comparable to the incident wavelength. The diplexer theoretically and experimentally exhibits a cross state bandwidth as broad as 2% of the operation frequency, with over 40-dB isolation between the cross and bar ports. We also demonstrate 1.5-Gbit/s frequency-division communication in the 0.32- and 0.33-THz bands using a single-wavelength-sized diplexer, and discuss the transmission bandwidth. Our study demonstrates the potential for application of photonic crystals as terahertz-wave integration platforms.

An exploratory pilot study to design and assess the credibility of a sham kinesiology treatment.

PubMed

Hall, Sue; Lewith, George; Brien, Sarah; Little, Paul

2008-12-01

Kinesiology is a complementary therapy assessing subtle change in manual muscle testing results to select individualised treatments. We report the exploratory 2-stage development and pilot of a sham kinesiology treatment for use in a clinical trial to evaluate the specific effects of this intervention. 1. To design, pilot and assess the credibility of a sham kinesiology treatment in a kinesiology-aware population. 2. To pilot the sham kinesiology in a cross-over study of sham versus real kinesiology, and to make an exploratory assessment of its credibility in a kinesiology-naïve population. 1. 10 kinesiology-aware volunteers received a specially designed sham treatment weekly for 5 weeks which was subject to a credibility assessment. 2. 10 kinesiology-naïve patients with low back pain were randomised to receive 4 real and 4 sham treatments in a cross-over design; the treatments were subject to a credibility assessment. 100% of participants found the sham protocol a credible treatment as measured by the credibility questionnaire. 100% of patients having real treatment first did not recognise that the second set of treatments were sham. Small numbers precluded the use of formal statistical tests. In this small sample it appeared feasible to deliver an apparently credible sham kinesiology treatment. This feasibility study has allowed us to develop a sham treatment for use in a larger prospective clinical trial of kinesiology in patients with low back pain. 2008 S. Karger AG, Basel.

Tobacco use among designated air pollution victims and its association with lung function and respiratory symptoms: a retrospective cross-sectional study

PubMed Central

Kotaki, Kenji; Senjyu, Hideaki; Tanaka, Takako; Yano, Yudai; Miyamoto, Naomi; Nishinakagawa, Tsuyoshi; Yanagita, Yorihide; Asai, Masaharu; Kozu, Ryo; Tabusadani, Mitsuru; Sawai, Terumitsu; Honda, Sumihisa

2014-01-01

Objectives We sought to elucidate the long-term association of tobacco use and respiratory health in designated pollution victims with and without obstructive pulmonary defects. Design A retrospective cross-sectional study. Setting The register of pollution victims in Kurashiki, Japan. Participants 730 individuals over 65 years of age previously diagnosed with pollution-related respiratory disease. Patients were classified into four groups according to their smoking status and whether they had obstructive pulmonary disease. We then compared the prevalence of respiratory symptoms and lung function over time between groups. Primary outcome measures Spirometry was performed and a respiratory health questionnaire completed in the same season each year for up to 30 years. Results Rates of smoking and respiratory disease were high in our sample. Although respiratory function in non-smoking patients did not completely recover, the annual rate of change in lung function was within the normal range (p<0.01). However, smokers had worse lung function and were more likely to report more severe pulmonary symptoms (p<0.01). Conclusions Patients’ respiratory function did not fully recover despite improved air quality. Our results suggest that, in the context of exposure to air pollution, tobacco use causes additional loss of lung function and exacerbates respiratory symptoms. PMID:25082419

NEUTRONIC REACTOR

DOEpatents

Wigner, E.P.

1958-04-22

A nuclear reactor for isotope production is described. This reactor is designed to provide a maximum thermal neutron flux in a region adjacent to the periphery of the reactor rather than in the center of the reactor. The core of the reactor is generally centrally located with respect tn a surrounding first reflector, constructed of beryllium. The beryllium reflector is surrounded by a second reflector, constructed of graphite, which, in tune, is surrounded by a conventional thermal shield. Water is circulated through the core and the reflector and functions both as a moderator and a coolant. In order to produce a greatsr maximum thermal neutron flux adjacent to the periphery of the reactor rather than in the core, the reactor is designed so tbat the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the materials in the reflector is approximately twice the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the material of the core of the reactor.

Predicting Oral Health-Related Behaviour in the Parents of Preschool Children: An Application of the Theory of Planned Behaviour

ERIC Educational Resources Information Center

Van den Branden, Sigrid; Van den Broucke, Stephan; Leroy, Roos; Declerck, Dominique; Hoppenbrouwers, Karel

2015-01-01

Objective: This study aimed to test the predictive validity of the Theory of Planned Behaviour (TPB) when applied to the oral health-related behaviours of parents towards their preschool children in a cross-sectional and prospective design over a 5-year interval. Methods: Data for this study were obtained from parents of 1,057 children born…

The Effect of Music Therapy Services on Classroom Behaviours of Newly Arrived Refugee Students in Australia--A Pilot Study

ERIC Educational Resources Information Center

Baker, Felicity; Jones, Carolyn

2006-01-01

This pilot study examined the effects of a short-term music therapy program on the classroom behaviours of newly arrived refugee students who were attending an intensive "English as a Second Language" secondary school. A cross-over design with two five-week intervention periods was employed with group music therapy sessions conducted one…

Bidirectional Interference between Speech and Nonspeech Tasks in Younger, Middle-Aged, and Older Adults

ERIC Educational Resources Information Center

Bailey, Dallin J.; Dromey, Christopher

2015-01-01

Purpose: The purpose of this study was to examine divided attention over a large age range by looking at the effects of 3 nonspeech tasks on concurrent speech motor performance. The nonspeech tasks were designed to facilitate measurement of bidirectional interference, allowing examination of their sensitivity to speech activity. A cross-sectional…

International Graduate Students' Cross-Cultural Academic Engagement: Stories of Indonesian Doctoral Students on an American Campus

ERIC Educational Resources Information Center

Mukminin, Amirul; McMahon, Brenda J.

2013-01-01

The purpose of this study was to explore the lived experience of academic engagement of twelve Indonesian doctoral students attending an American graduate school during their first term and over time through demographic background surveys and semi-structured in-depth interviews. The research design was qualitative in the phenomenological approach…

A Low Cross-Polarization Smooth-Walled Horn with Improved Bandwidth

NASA Technical Reports Server (NTRS)

Zeng, Lingzhen; Bennette, Charles L.; Chuss, David T.; Wollack, Edward J.

2009-01-01

Corrugated feed horns offer excellent beam symmetry, main beam efficiency, and cross-polar response over wide bandwidths, but can be challenging to fabricate. An easier-to-manufacture smooth-walled feed is explored that approximates these properties over a finite bandwidth. The design, optimization and measurement of a monotonically-profiled, smooth-walled scalar feedhorn with a diffraction-limited approx. 14deg FWHM beam is presented. The feed was demonstrated to have low cross polarization (<-30 dB) across the frequency range 33-45 GHz (30% fractional bandwidth). A power reflection below -28 dB was measured across the band.

Combat Conditioning: The Need for Stronger Marines

DTIC Science & Technology

2008-02-18

shows how the average weight carried by warriors has increased over time. 3 “ CrossFit is a core strength and conditioning program...We have designed our program to elicit as broad an adaptational response as possible. CrossFit is not a specialized fitness program but a

Low latency adaptive streaming of HD H.264 video over 802.11 wireless networks with cross-layer feedback

NASA Astrophysics Data System (ADS)

Patti, Andrew; Tan, Wai-tian; Shen, Bo

2007-09-01

Streaming video in consumer homes over wireless IEEE 802.11 networks is becoming commonplace. Wireless 802.11 networks pose unique difficulties for streaming high definition (HD), low latency video due to their error-prone physical layer and media access procedures which were not designed for real-time traffic. HD video streaming, even with sophisticated H.264 encoding, is particularly challenging due to the large number of packet fragments per slice. Cross-layer design strategies have been proposed to address the issues of video streaming over 802.11. These designs increase streaming robustness by imposing some degree of monitoring and control over 802.11 parameters from application level, or by making the 802.11 layer media-aware. Important contributions are made, but none of the existing approaches directly take the 802.11 queuing into account. In this paper we take a different approach and propose a cross-layer design allowing direct, expedient control over the wireless packet queue, while obtaining timely feedback on transmission status for each packet in a media flow. This method can be fully implemented on a media sender with no explicit support or changes required to the media client. We assume that due to congestion or deteriorating signal-to-noise levels, the available throughput may drop substantially for extended periods of time, and thus propose video source adaptation methods that allow matching the bit-rate to available throughput. A particular H.264 slice encoding is presented to enable seamless stream switching between streams at multiple bit-rates, and we explore using new computationally efficient transcoding methods when only a high bit-rate stream is available.

Global positive expectancies in adolescence and health-related behaviours: Longitudinal models of latent growth and cross-lagged effects

PubMed Central

Carvajal, Scott C.

2015-01-01

Constructs representative of global positive expectancies (GPE) such as dispositional optimism and hope have been theoretically and empirically linked to many positive mental and physical health outcomes. However such expectancies’ health implications for adolescents, as well as their trajectory over time, are less well understood than for adult populations. This study tested whether GPE predict the key indicators of adolescents’ future physical health status, their health-related behaviours. A prospective longitudinal study design was employed whereby a diverse population-based cohort (N = 744; mean age at baseline = 12) completed three surveys over approximately 18 months. Rigorous tests of causal predominance and reciprocal effects were conducted through latent growth and cross-panel structural equation models. Results showed GPE systematically decreased during the course of the study, yet higher initial levels of GPE predicted less alcohol drinking, healthier food choice and greater physical activity over time. GPE’s protective relationships towards health protective behaviours (vs. health risk behaviours that also included tobacco smoking) appear more independent from depressive symptomatology, and the primary findings were robust across socio-demographic groups. PMID:22149606

Ultra-low crosstalk, CMOS compatible waveguide crossings for densely integrated photonic interconnection networks.

PubMed

Jones, Adam M; DeRose, Christopher T; Lentine, Anthony L; Trotter, Douglas C; Starbuck, Andrew L; Norwood, Robert A

2013-05-20

We explore the design space for optimizing CMOS compatible waveguide crossings on a silicon photonics platform. This paper presents simulated and experimental excess loss and crosstalk suppression data for vertically integrated silicon nitride over silicon-on-insulator waveguide crossings. Experimental results show crosstalk suppression exceeding -49/-44 dB with simulation results as low as -65/-60 dB for the TE/TM mode in a waveguide crossing with a 410 nm vertical gap.

Mobile Application vs Paper Pictorial Blood Assessment Chart to Track Menses in Young Women: A Randomized Cross-over Design.

PubMed

Jacobson, Amanda E; Vesely, Sara K; Haamid, Fareeda; Christian-Rancy, Myra; O'Brien, Sarah H

2018-04-01

Heavy menstrual bleeding is a common symptom reported by approximately 30% of women. The Pictorial Blood Assessment Chart (PBAC) score is often used to quantify severity of menstrual bleeding. However, the traditional PBAC paper diary might be subject to recall bias and compliance issues, especially in adolescents. We developed a mobile application (app) version of the PBAC score and evaluated patient satisfaction and compliance with app reporting vs paper reporting. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: This study was a randomized cross-over study of 25 postmenarchal female adolescents and young women ages 13-21 years. Participants agreed to track bleeding in 2 consecutive menstrual cycles and were randomized to use the PBAC paper diary or mobile app format first. At the end of each cycle, a satisfaction survey and system usability scale (app only) was used to assess the acceptability of the format used. Twenty-five participants had a median age of 15 years. Cross-over analysis showed that satisfaction level was significantly higher for the app (P < .001). Twenty of 25 (80%) participants preferred the app over the paper diary. For the app, 20 of 25 participants (80%) had high compliance for reporting bleeding, with a mean of 2 app entries per day. Participants' PBAC scores did not vary significantly between the paper diary (median, 95) and mobile app (median, 114). All paper diaries met definition for high compliance. There was no significant period or carryover effect. This study showed that a PBAC app compared with the paper diary was the preferred method of recording menstrual bleeding in adolescents and showed feasibility as a research data collection tool. Copyright © 2017 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Methodological considerations in a pilot study on the effects of a berry enriched smoothie on children’s performance in school

PubMed Central

Rosander, Ulla; Rumpunen, Kimmo; Olsson, Viktoria; Åström, Mikael; Rosander, Pia; Wendin, Karin

2017-01-01

ABSTRACT Berries contain bioactive compounds that may affect children’s cognitive function positively, while hunger and thirst during lessons before lunch affect academic performance negatively. This pilot study addresses methodological challenges in studying if a berry smoothie, offered to schoolchildren as a mid-morning beverage, affects academic performance. The objective was to investigate if a cross-over design can be used to study these effects in a school setting. Therefore, in order to investigate assay sensitivity, 236 Swedish children aged 10–12 years were administered either a berry smoothie (active) or a fruit-based control beverage after their mid-morning break. Both beverages provided 5% of child daily energy intake. In total, 91% of participants completed the study. Academic performance was assessed using the d2 test of attention. Statistical analyses were performed using the Wilcoxon signed rank test in StatXact v 10.3. The results showed that the children consumed less of the active berry smoothie than the control (154 g vs. 246 g). Both beverages increased attention span and concentration significantly (p = 0.000). However, as there was no significant difference (p = 0.938) in the magnitude of this effect between the active and control beverages, the assay sensitivity of the study design was not proven. The effect of the beverages on academic performance was attributed the supplementation of water and energy. Despite careful design, the active smoothie was less accepted than the control. This could be explained by un-familiar sensory characteristics and peer influence, stressing the importance of sensory similarity and challenges to perform a study in school settings. The employed cross-over design did not reveal any effects of bioactive compound consumption on academic performance. In future studies, the experimental set up should be modified or replaced by e.g. the parallel study design, in order to provide conclusive results. PMID:29230155

Methodological considerations in a pilot study on the effects of a berry enriched smoothie on children's performance in school.

PubMed

Rosander, Ulla; Rumpunen, Kimmo; Olsson, Viktoria; Åström, Mikael; Rosander, Pia; Wendin, Karin

2017-01-01

Berries contain bioactive compounds that may affect children's cognitive function positively, while hunger and thirst during lessons before lunch affect academic performance negatively. This pilot study addresses methodological challenges in studying if a berry smoothie, offered to schoolchildren as a mid-morning beverage, affects academic performance. The objective was to investigate if a cross-over design can be used to study these effects in a school setting. Therefore, in order to investigate assay sensitivity, 236 Swedish children aged 10-12 years were administered either a berry smoothie (active) or a fruit-based control beverage after their mid-morning break. Both beverages provided 5% of child daily energy intake. In total, 91% of participants completed the study. Academic performance was assessed using the d2 test of attention. Statistical analyses were performed using the Wilcoxon signed rank test in StatXact v 10.3. The results showed that the children consumed less of the active berry smoothie than the control (154 g vs. 246 g). Both beverages increased attention span and concentration significantly (p = 0.000). However, as there was no significant difference (p = 0.938) in the magnitude of this effect between the active and control beverages, the assay sensitivity of the study design was not proven. The effect of the beverages on academic performance was attributed the supplementation of water and energy. Despite careful design, the active smoothie was less accepted than the control. This could be explained by un-familiar sensory characteristics and peer influence, stressing the importance of sensory similarity and challenges to perform a study in school settings. The employed cross-over design did not reveal any effects of bioactive compound consumption on academic performance. In future studies, the experimental set up should be modified or replaced by e.g. the parallel study design, in order to provide conclusive results.

Methodology Series Module 3: Cross-sectional Studies.

PubMed

Setia, Maninder Singh

2016-01-01

Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case-control studies (participants selected based on the outcome status) or cohort studies (participants selected based on the exposure status), the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design.

Methodology Series Module 3: Cross-sectional Studies

PubMed Central

Setia, Maninder Singh

2016-01-01

Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case–control studies (participants selected based on the outcome status) or cohort studies (participants selected based on the exposure status), the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design. PMID:27293245

Designing an upgrade of the Medley setup for light-ion production and fission cross-section measurements

NASA Astrophysics Data System (ADS)

Jansson, K.; Gustavsson, C.; Al-Adili, A.; Hjalmarsson, A.; Andersson-Sundén, E.; Prokofiev, A. V.; Tarrío, D.; Pomp, S.

2015-09-01

Measurements of neutron-induced fission cross-sections and light-ion production are planned in the energy range 1-40 MeV at the upcoming Neutrons For Science (NFS) facility. In order to prepare our detector setup for the neutron beam with continuous energy spectrum, a simulation software was written using the Geant4 toolkit for both measurement situations. The neutron energy range around 20 MeV is troublesome when it comes to the cross-sections used by Geant4 since data-driven cross-sections are only available below 20 MeV but not above, where they are based on semi-empirical models. Several customisations were made to the standard classes in Geant4 in order to produce consistent results over the whole simulated energy range. Expected uncertainties are reported for both types of measurements. The simulations have shown that a simultaneous precision measurement of the three standard cross-sections H(n,n), 235U(n,f) and 238U(n,f) relative to each other is feasible using a triple layered target. As high resolution timing detectors for fission fragments we plan to use Parallel Plate Avalanche Counters (PPACs). The simulation results have put some restrictions on the design of these detectors as well as on the target design. This study suggests a fissile target no thicker than 2 μm (1.7 mg/cm2) and a PPAC foil thickness preferably less than 1 μm. We also comment on the usability of Geant4 for simulation studies of neutron reactions in this energy range.

College Student's Health, Drinking and Smoking Patterns: What Has Changed in 20 Years?

ERIC Educational Resources Information Center

Hensel, Desiree; Todd, Katherine Leigh; Engs, Ruth C.

2014-01-01

Problem: Institutes of higher learning are increasingly trying to address the issue of problem drinking. The purpose of this study was to determine how patterns in alcohol use and smoking by college students, as well as their illness patterns, have changed over 20 years. Methods: A cross-sectional serial survey design was used for this descriptive…

A Cross-Cultural Usability Study on the Internationalization of User Interfaces Based on an Empirical Five Factor Model

ERIC Educational Resources Information Center

Chakraborty, Joyram

2009-01-01

With the internationalization of e-commerce, it is no longer viable to design one user interface for all environments. Web-based applications and services can be accessed from all over the globe. To account for this globalization process, software developers need to understand that simply accounting for language translation of their websites for…

University Students' Attainment and Perceptions of Computer Delivered Assessment; A Comparison between Computer-Based and Traditional Tests in a "High-Stakes" Examination

ERIC Educational Resources Information Center

Escudier, M. P.; Newton, T. J.; Cox, M. J.; Reynolds, P. A.; Odell, E. W.

2011-01-01

This study compared higher education dental undergraduate student performance in online assessments with performance in traditional paper-based tests and investigated students' perceptions of the fairness and acceptability of online tests, and showed performance to be comparable. The project design involved two parallel cross-over trials, one in…

Adolescents' TV Viewing Patterns in the Digital Era: A Cross-Cultural Study

ERIC Educational Resources Information Center

Ugalde, Leire; Martínez-de-Morentin, Juan-Ignacio; María-Concepción Medrano

2017-01-01

The deep-rooted changes that have taken place in the media world over recent years have brought about changes in both television itself and in the relationships established with this medium. Consequently, it is important to understand how young people watch television today, in order to design strategies to help them develop the capacities they…

Efficacy of triclosan as an antimicrobial hand soap and its potential impact on antimicrobial resistance: a focused review.

PubMed

Giuliano, Christopher A; Rybak, Michael J

2015-03-01

Triclosan is a synthetic biocide found in many household products, including antimicrobial hand soap. Levels of triclosan have been found throughout the environment and in human urine, blood, and even breast milk. Increasing levels of exposure to triclosan have led to concerns over the development of resistance to triclosan and cross-resistance to other antimicrobials. We performed a literature search to assess whether the widespread use of triclosan displays a favorable benefit: risk ratio, defined by evaluation of triclosan's efficacy as an antimicrobial hand soap and its potential effect on the development of antimicrobial resistance. Data from laboratory-based studies regarding the efficacy of triclosan are conflicting, although well-designed studies suggest no significant difference in efficacy over nonantimicrobial soap. In addition, when triclosan was introduced in a community setting, no beneficial effects were observed on the reduction of infections over nonantimicrobial soap. Resistance to triclosan and cross-resistance to antimicrobials have been consistently demonstrated in laboratory settings, although overall resistance rates and cross-resistance rates in the community setting are low. Based on the available evidence, the risk of potential antimicrobial resistance outweighs the benefit of widespread triclosan use in antimicrobial soaps. © 2015 Pharmacotherapy Publications, Inc.

TreeNetViz: revealing patterns of networks over tree structures.

PubMed

Gou, Liang; Zhang, Xiaolong Luke

2011-12-01

Network data often contain important attributes from various dimensions such as social affiliations and areas of expertise in a social network. If such attributes exhibit a tree structure, visualizing a compound graph consisting of tree and network structures becomes complicated. How to visually reveal patterns of a network over a tree has not been fully studied. In this paper, we propose a compound graph model, TreeNet, to support visualization and analysis of a network at multiple levels of aggregation over a tree. We also present a visualization design, TreeNetViz, to offer the multiscale and cross-scale exploration and interaction of a TreeNet graph. TreeNetViz uses a Radial, Space-Filling (RSF) visualization to represent the tree structure, a circle layout with novel optimization to show aggregated networks derived from TreeNet, and an edge bundling technique to reduce visual complexity. Our circular layout algorithm reduces both total edge-crossings and edge length and also considers hierarchical structure constraints and edge weight in a TreeNet graph. These experiments illustrate that the algorithm can reduce visual cluttering in TreeNet graphs. Our case study also shows that TreeNetViz has the potential to support the analysis of a compound graph by revealing multiscale and cross-scale network patterns. © 2011 IEEE

A promising method for identifying cross-cultural differences in patient perspective: the use of Internet-based focus groups for content validation of new Patient Reported Outcome assessments

PubMed Central

Atkinson, Mark J; Lohs, Jan; Kuhagen, Ilka; Kaufman, Julie; Bhaidani, Shamsu

2006-01-01

Objectives This proof of concept (POC) study was designed to evaluate the use of an Internet-based bulletin board technology to aid parallel cross-cultural development of thematic content for a new set of patient-reported outcome measures (PROs). Methods The POC study, conducted in Germany and the United States, utilized Internet Focus Groups (IFGs) to assure the validity of new PRO items across the two cultures – all items were designed to assess the impact of excess facial oil on individuals' lives. The on-line IFG activities were modeled after traditional face-to-face focus groups and organized by a common 'Topic' Guide designed with input from thought leaders in dermatology and health outcomes research. The two sets of IFGs were professionally moderated in the native language of each country. IFG moderators coded the thematic content of transcripts, and a frequency analysis of code endorsement was used to identify areas of content similarity and difference between the two countries. Based on this information, draft PRO items were designed and a majority (80%) of the original participants returned to rate the relative importance of the newly designed questions. Findings The use of parallel cross-cultural content analysis of IFG transcripts permitted identification of the major content themes in each country as well as exploration of the possible reasons for any observed differences between the countries. Results from coded frequency counts and transcript reviews informed the design and wording of the test questions for the future PRO instrument(s). Subsequent ratings of item importance also deepened our understanding of potential areas of cross-cultural difference, differences that would be explored over the course of future validation studies involving these PROs. Conclusion The use of IFGs for cross-cultural content development received positive reviews from participants and was found to be both cost and time effective. The novel thematic coding methodology provided an empirical platform on which to develop culturally sensitive questionnaire content using the natural language of participants. Overall, the IFG responses and thematic analyses provided a thorough evaluation of similarities and differences in cross-cultural themes, which in turn acted as a sound base for the development of new PRO questionnaires. PMID:16995935

A promising method for identifying cross-cultural differences in patient perspective: the use of Internet-based focus groups for content validation of new patient reported outcome assessments.

PubMed

Atkinson, Mark J; Lohs, Jan; Kuhagen, Ilka; Kaufman, Julie; Bhaidani, Shamsu

2006-09-22

This proof of concept (POC) study was designed to evaluate the use of an Internet-based bulletin board technology to aid parallel cross-cultural development of thematic content for a new set of patient-reported outcome measures (PROs). The POC study, conducted in Germany and the United States, utilized Internet Focus Groups (IFGs) to assure the validity of new PRO items across the two cultures--all items were designed to assess the impact of excess facial oil on individuals' lives. The on-line IFG activities were modeled after traditional face-to-face focus groups and organized by a common 'Topic' Guide designed with input from thought leaders in dermatology and health outcomes research. The two sets of IFGs were professionally moderated in the native language of each country. IFG moderators coded the thematic content of transcripts, and a frequency analysis of code endorsement was used to identify areas of content similarity and difference between the two countries. Based on this information, draft PRO items were designed and a majority (80%) of the original participants returned to rate the relative importance of the newly designed questions. The use of parallel cross-cultural content analysis of IFG transcripts permitted identification of the major content themes in each country as well as exploration of the possible reasons for any observed differences between the countries. Results from coded frequency counts and transcript reviews informed the design and wording of the test questions for the future PRO instrument(s). Subsequent ratings of item importance also deepened our understanding of potential areas of cross-cultural difference, differences that would be explored over the course of future validation studies involving these PROs. The use of IFGs for cross-cultural content development received positive reviews from participants and was found to be both cost and time effective. The novel thematic coding methodology provided an empirical platform on which to develop culturally sensitive questionnaire content using the natural language of participants. Overall, the IFG responses and thematic analyses provided a thorough evaluation of similarities and differences in cross-cultural themes, which in turn acted as a sound base for the development of new PRO questionnaires.

Testing the reciprocal associations among co-worker incivility, organisational inefficiency, and work-related exhaustion: A one-year, cross-lagged study

PubMed Central

Viotti, Sara; Essenmacher, Lynnette; Hamblin, Lydia E.; Arnetz, Judith E.

2018-01-01

In spite of the considerable number of studies on co-worker incivility, knowledge on this topic needs to be further enhanced. In particular, no studies have focused on the reciprocal nature of the relationship of incivility with other important aspects of working life, i.e. employee well-being and the quality of the working process. The aim of the present study was to examine the cross-lagged associations among co-worker incivility, work-related exhaustion, and organisational efficiency in a sample of healthcare workers. Based on the conservation of resource theory, we hypothesised that those three variables affect each other reciprocally over the time. Data from a two-wave study design (with a one-year time lag) were utilised, and cross-lagged structural equation models were performed. Results confirmed that incivility and efficiency affected each other reciprocally over time. On the other hand, whereas incivility positively predicted exhaustion and exhaustion at inversely predicted organisational efficiency, the opposite paths were found to be not significant. The study suggests that efficiency is crucial for understanding incivility because it operates both as its cause and as its outcome. Interventions aimed at promoting civility and respect in the workplace may help prevent co-worker incivility, work-related exhaustion, and enhance organisational efficiency.

Testing the reciprocal associations among co-worker incivility, organisational inefficiency, and work-related exhaustion: A one-year, cross-lagged study.

PubMed

Viotti, Sara; Essenmacher, Lynnette; Hamblin, Lydia E; Arnetz, Judith E

2018-01-01

In spite of the considerable number of studies on co-worker incivility, knowledge on this topic needs to be further enhanced. In particular, no studies have focused on the reciprocal nature of the relationship of incivility with other important aspects of working life, i.e. employee well-being and the quality of the working process. The aim of the present study was to examine the cross-lagged associations among co-worker incivility, work-related exhaustion, and organisational efficiency in a sample of healthcare workers. Based on the conservation of resource theory, we hypothesised that those three variables affect each other reciprocally over the time. Data from a two-wave study design (with a one-year time lag) were utilised, and cross-lagged structural equation models were performed. Results confirmed that incivility and efficiency affected each other reciprocally over time. On the other hand, whereas incivility positively predicted exhaustion and exhaustion at inversely predicted organisational efficiency, the opposite paths were found to be not significant. The study suggests that efficiency is crucial for understanding incivility because it operates both as its cause and as its outcome. Interventions aimed at promoting civility and respect in the workplace may help prevent co-worker incivility, work-related exhaustion, and enhance organisational efficiency.

Engineering Analysis Studies for Preliminary Design of Lightweight Cryogenic Hydrogen Tanks in UAV Applications

NASA Technical Reports Server (NTRS)

Sullivan, Roy M.; Palko, Joseph L.; Tornabene, Robert T.; Bednarcyk, Brett A.; Powers, Lynn M.; Mital, Subodh K.; Smith, Lizalyn M.; Wang, Xiao-Yen J.; Hunter, James E.

2006-01-01

A series of engineering analysis studies were conducted to investigate the potential application of nanoclay-enhanced graphite/epoxy composites and polymer cross-linked silica aerogels in cryogenic hydrogen storage tank designs. This assessment focused on the application of these materials in spherical tank designs for unmanned aeronautic vehicles with mission durations of 14 days. Two cryogenic hydrogen tank design concepts were considered: a vacuum-jacketed design and a sandwiched construction with an aerogel insulating core. Analyses included thermal and structural analyses of the tank designs as well as an analysis of hydrogen diffusion to specify the material permeability requirements. The analyses also provided material property targets for the continued development of cross-linked aerogels and nanoclay-enhanced graphite/epoxy composites for cryogenic storage tank applications. The results reveal that a sandwiched construction with an aerogel core is not a viable design solution for a 14-day mission. A vacuum-jacketed design approach was shown to be far superior to an aerogel. Aerogel insulation may be feasible for shorter duration missions. The results also reveal that the application of nanoclay-enhanced graphite/epoxy should be limited to the construction of outer tanks in a vacuum-jacketed design, since a graphite/epoxy inner tank does not provide a significant weight savings over aluminum and since the ability of nanoclay-enhanced graphite/epoxy to limit hydrogen permeation is still in question.

A Multicenter Approach Evaluating the Impact of Vitamin E-Blended Polyethylene in Cementless Total Hip Replacement

PubMed Central

Jäger, Marcus; van Wasen, Andrea; Warwas, Sebastian; Landgraeber, Stefan; Haversath, Marcel; Group, VITAS

2014-01-01

Since polyethylene is one of the most frequently used biomaterials as a liner in total hip arthroplasty, strong efforts have been made to improve design and material properties over the last 50 years. Antioxidants seems to be a promising alternative to further increase durability and reduce polyethylene wear in long term. As of yet, only in vitro results are available. While they are promising, there is yet no clinical evidence that the new material shows these advantages in vivo. To answer the question if vitamin-E enhanced ultra-high molecular weight polyethylene (UHMWPE) is able to improve long-term survivorship of cementless total hip arthroplasty we initiated a randomized long-term multicenter trial. Designed as a superiority study, the oxidation index assessed in retrieval analyses of explanted liners was chosen as primary parameter. Radiographic results (wear rate, osteolysis, radiolucency) and functional outcome (Harris Hip Scores, University of California-Los Angeles, Hip Disability and Osteoarthritis Outcome Score, Visual Analogue Scale) will serve as secondary parameters. Patients with the indication for a cementless total hip arthroplasty will be asked to participate in the study and will be randomized to either receive a standard hip replacement with a highly cross-linked UHMWPE-X liner or a highly cross-linked vitamin-E supplemented UHMWPE-XE liner. The follow-up will be 15 years, with evaluation after 5, 10 and 15 years. The controlled randomized study has been designed to determine if Vitamin-E supplemented highly cross-linked polyethylene liners are superior to standard XLPE liners in cementless total hip arthroplasty. While several studies have been started to evaluate the influence of vitamin-E, most of them evaluate wear rates and functional results. The approach used for this multicenter study, to analyze the oxidation status of retrieved implants, should make it possible to directly evaluate the ageing process and development of the implant material itself over a time period of 15 years. PMID:25002933

77 FR 40370 - Agency Information Collection Activities: Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-09

... enhanced and standard data collection and a longitudinal cohort design, and will include a comparative...-site evaluation design includes a process and an outcome evaluation and data will be collected over a 3-year period from 7 grantee sites. The cross-site evaluation is designed to address the following...

Evaluation of AM2 2 1 Lay Pattern Over a 25 CBR Subgrade

DTIC Science & Technology

2018-04-30

penetrometer in shallow pavement applications. Designation : D 6951. West Conshohocken, PA: ASTM International. ____. 2010. Standard test method for...Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO...27 Figure 3.21. Surveying designated cross section

Efficacy of Fluon conditioning for capturing cerambycid beetles in different trap designs and rersistence on panel traps over time

Treesearch

Elizabeth E. Graham; Therese M. Poland

2012-01-01

Fluon PTFE is a fluoropolymer dispersion applied as a surface conditioner to cross-vane panel traps to enhance trap efficiency for cerambycid beetles. We describe the results of three experiments to further optimize cerambycid traps of different designs and to test the effect of Fluon over time. We tested Fluon with Lindgren funnel and panel traps fitted with either...

The Health Behaviour in School-aged Children: WHO Collaborative Cross-National (HBSC) study: origins, concept, history and development 1982-2008.

PubMed

Currie, Candace; Nic Gabhainn, Saoirse; Godeau, Emmanuelle

2009-09-01

This paper traces the history of the HBSC study from its origins in the early 1980's to the present day describing how it was first conceptualised scientifically and how this influenced issues of study design. The challenges of managing a cross-national study are explained as are changes and adaptations over time with growth of the study from 3 to over forty country members. The key partnership with the World Health Organisation and its benefits are presented. With developments in scientific management and theoretical perspectives, HBSC has made a substantial contribution to the area of youth health. The last decade has seen increased dissemination to policy makers and evidence that scientific information arising from the study has influenced strategic policy development and practical health improvement programmes. This paper considers some of the key success factors and challenges for the study as it attempts to maximise its scientific output and channels the research findings into health improvement for young people. Future challenges for the study are also considered.

Cross-Sectional and Longitudinal Comparisons of Adolescent Self-Esteem.

ERIC Educational Resources Information Center

Mullis, Ann K.; And Others

1992-01-01

Examined self-esteem of adolescents over three years of high school. Ninth graders (n=270) completed Coopersmith Self-Esteem Inventory for each of three years. Found grade level significantly related to self-esteem in longitudinal but not cross-sectional design. Mediational effects of gender and socioeconomic status were found to be minimal.…

A randomized, single-blind cross-over design evaluating the effectiveness of an individually defined, targeted physical therapy approach in treatment of children with cerebral palsy.

PubMed

Franki, Inge; Van den Broeck, Christine; De Cat, Josse; Tijhuis, Wieke; Molenaers, Guy; Vanderstraeten, Guy; Desloovere, Kaat

2014-10-01

A pilot study to compare the effectiveness of an individual therapy program with the effects of a general physical therapy program. A randomized, single-blind cross-over design. Ten ambulant children with bilateral spastic cerebral palsy, age four to nine years. Participants were randomly assigned into a ten-week individually defined, targeted or a general program, followed by a cross-over. Evaluation was performed using the Gross Motor Function Measure-88 and three-dimensional gait analysis. General outcome parameters were Gross Motor Function Measure-88 scores, time and distance parameters, gait profile score and movement analysis profiles. Individual goal achievement was evaluated using z-scores for gait parameters and Goal Attainment Scale for gross motor function. No significant changes were observed regarding gross motor function. Only after individualized therapy, step- and stride-length increased significantly (p = 0.022; p = 0.017). Change in step-length was higher after the individualized program (p = 0.045). Within-group effects were found for the pelvis in transversal plane after the individualized program (p = 0.047) and in coronal plane after the general program (p = 0.047). Between-program differences were found for changes in the knee in sagittal plane, in the advantage of the individual program (p = 0.047). A median difference in z-score of 0.279 and 0.419 was measured after the general and individualized program, respectively. Functional goal attainment was higher after the individual therapy program compared with the general program (48 to 43.5). The results indicate slightly favorable effects towards the individualized program. To detect clinically significant changes, future studies require a minimal sample size of 72 to 90 participants. © The Author(s) 2014.

Navigating the network: signaling cross-talk in hematopoietic cells

PubMed Central

Fraser, Iain D C; Germain, Ronald N

2009-01-01

Recent studies in hematopoietic cells have led to a growing appreciation of the diverse modes of molecular and functional cross-talk between canonical signaling pathways. However, these intersections represent only the tip of the iceberg. Emerging global analytical methods are providing an even richer and more complete picture of the many components that measurably interact in a network manner to produce cellular responses. Here we highlight the pieces in this Focus, emphasize the limitations of the present canonical pathway paradigm, and discuss the value of a systems biology approach using more global, quantitative experimental design and data analysis strategies. Lastly, we urge caution about overly facile interpretation of genome- and proteome-level studies. PMID:19295628

A Multiyear Assessment of Public Response to a Statewide Drug Take-Back and Disposal Campaign, 2010 to 2012

ERIC Educational Resources Information Center

Yanovitzky, Itzhak

2017-01-01

This study is the first to analyze public response to a drug take-back program, the American Medicine Chest Challenge, in a single state over a period of 3 years (2010-2012). The study utilized a three-wave repeated cross-sectional design and an annual phone survey conducted with a representative sample of adults (N = 906 in 2010, N = 907 in 2011,…

Dish stirling solar receiver combustor test program

NASA Technical Reports Server (NTRS)

Bankston, C. P.; Back, L. H.

1981-01-01

The operational and energy transfer characteristics of the Dish Stirling Solar Receiver (DSSR) combustor/heat exchanger system was evaluated. The DSSR is designed to operate with fossil fuel augmentation utilizing a swirl combustor and cross flow heat exchanger consisting of a single row of 4 closely spaced tubes that are curved into a conical shape. The performance of the combustor/heat exchanger system without a Stirling engine was studied over a range of operating conditions and output levels using water as the working fluid. Results show that the combustor may be started under cold conditions, controlled safety, and operated at a constant air/fuel ratio (10 percent excess air) over the required range of firing rates. Furthermore, nondimensional heat transfer coefficients based on total heat transfer are plotted versus Reynolds number and compared with literature data taken for single rows of closely spaced tubes perpendicular to cross flow. The data show enhanced heat transfer for the present geometry and test conditions. Analysis of the results shows that the present system meets specified thermal requirements, thus verifying the feasibility of the DSSR combustor design for final prototype fabrication.

[Structural Damage to the Hamstring Graft due to Interaction with Fixation Material and its Effect on Biomechanical Properties of ACL Reconstruction].

PubMed

Kautzner, J; Držík, M; Handl, M; Povýšil, C; Kos, P; Trč, T; Havlas, V

2017-01-01

PURPOSE OF THE STUDY Hamstring grafts are commonly used for ACL reconstruction. The purpose of our study is to determine the effects of the suspension fixation compared to graft cross-pinning transfixation, and the effect(s) of structural damage during the preparation of the graft on biomechanical properties of the graft. MATERIAL AND METHODS The design of the study is a cadaveric biomechanical laboratory study. 38 fresh-frozen human hamstring specimens from 19 cadaveric donors were used. The grafts were tested for their loading properties. One half of each specimen was suspended over a 3.3mm pin, the other half was cross-pinned by a 3.3mm pin to simulate the graft cross-pinning technique. Single impact testing was performed and the failure force, elongation and acceleration/deceleration of each graft was recorded and the loading force vs. elongation of the graft specimens was calculated. Results for suspended and cross-pinned grafts were analysed using ANOVA method, comparing the grafts from each donor. RESULTS The ultimate strength of a double-strand gracilis graft was 1287 ± 134 N when suspended over a pin, the strength of a cross-pinned graft was 833 ± 111 N. For double-strand semitendinosus grafts the strengths were 1883 ± 198 and 997 ± 234 N, respectively. Thus, the failure load for the cross-pinning method is only 64.7% or 52.9% for the suspension method. DISCUSSION Structural damage to the graft significantly reduces the graft strength. Also, extensive suturing during preparation of the graft reduces its strength. CONCLUSIONS Fixation methods that do not interfere with the graft's structure should be used to reduce the risk of graft failure. Key words: ACL reconstruction, hamstring graft, biomechanical testing.

Broadband high-efficiency half-wave plate: a supercell-based plasmonic metasurface approach.

PubMed

Ding, Fei; Wang, Zhuoxian; He, Sailing; Shalaev, Vladimir M; Kildishev, Alexander V

2015-04-28

We design, fabricate, and experimentally demonstrate an ultrathin, broadband half-wave plate in the near-infrared range using a plasmonic metasurface. The simulated results show that the linear polarization conversion efficiency is over 97% with over 90% reflectance across an 800 nm bandwidth. Moreover, simulated and experimental results indicate that such broadband and high-efficiency performance is also sustained over a wide range of incident angles. To further obtain a background-free half-wave plate, we arrange such a plate as a periodic array of integrated supercells made of several plasmonic antennas with high linear polarization conversion efficiency, consequently achieving a reflection-phase gradient for the cross-polarized beam. In this design, the anomalous (cross-polarized) and the normal (copolarized) reflected beams become spatially separated, hence enabling highly efficient and robust, background-free polarization conversion along with broadband operation. Our results provide strategies for creating compact, integrated, and high-performance plasmonic circuits and devices.

RELIABILITY AND VALIDITY OF FUNCTIONAL PERFORMANCE TESTS IN DANCERS WITH HIP DYSFUNCTION

PubMed Central

Carcia, Christopher R.; Clemente, F. Richard; Phelps, Amy L.; Martin, RobRoy L.

2013-01-01

Study Design: Quasi-experimental, repeated measures. Purpose/Background: Functional performance tests that identify hip joint impairments and assess the effect of intervention have not been adequately described for dancers. The purpose of this study was to examine the reliability and validity of hop and balance tests among a group of dancers with musculoskeletal pain in the hip region. Methods: Nineteen female dancers (age: 18.90±1.11 years; height: 164.85±6.95 cm; weight: 60.37±8.29 kg) with unilateral hip pain were assessed utilizing the cross-over reach, medial triple hop, lateral triple hop, and cross-over hop tests on two occasions, 2 days apart. Test-retest reliability and comparisons between the involved and uninvolved side for each respective test were determined. Results: Intra-class correlation coefficients for the functional performance tests ranged from 0.89-0.96. The cross-over reach test had a SEM of 2.79 cm and a MDC of 7.73 cm. The medial and lateral triple hop tests had SEM values of 7.51 cm and 8.17 cm, and MDC values of 20.81 cm and 22.62 cm, respectively. The SEM was 0.15 seconds and the MDC was 0.42 seconds for the cross-over hop test. Performance on the medial triple hop test was significantly less on the involved side (370.21±38.26 cm) compared to the uninvolved side (388.05±41.49 cm); t(18) = −4.33, p<0.01. The side-to-side comparisons of the cross-over reach test (involved mean=61.68±10.9 cm; uninvolved mean=61.69±8.63 cm); t(18) = −0.004, p=0.99, lateral triple hop test (involved mean=306.92±35.79 cm; uninvolved mean=310.68±24.49 cm); t(18) = −0.55, p=0.59, and cross-over hop test (involved mean=2.49±0.34 seconds; uninvolved mean= 2.61±0.42 seconds; t(18) = −1.84, p=0.08) were not statistically different between sides. Conclusion: The functional performance tests used in this study can be reliably performed on dancers with unilateral hip pain. The medial triple hop test was the only functional performance test with evidence of validity in side-to-side comparisons. These results suggest that the medial triple hop test may be a reliable and valid functional performance test to assess impairments related to hip pain among dancers. Level of Evidence: 3b. Non-consecutive cohort study PMID:24175123

Design of an Airborne L-Band Cross-Track Scanning Scatterometer

NASA Technical Reports Server (NTRS)

Hilliard, Lawrence M. (Technical Monitor)

2002-01-01

In this report, we describe the design of an airborne L-band cross-track scanning scatterometer suitable for airborne operation aboard the NASA P-3 aircraft. The scatterometer is being designed for joint operation with existing L-band radiometers developed by NASA for soil moisture and ocean salinity remote sensing. In addition, design tradeoffs for a space-based radar system have been considered, with particular attention given to antenna architectures suitable for sharing the antenna between the radar and radiometer. During this study, we investigated a number of imaging techniques, including the use of real and synthetic aperture processing in both the along track and cross-track dimensions. The architecture selected will permit a variety of beamforming algorithms to be implemented, although real aperture processing, with hardware beamforming, provides better sidelobe suppression than synthetic array processing and superior signal-to-noise performance. In our discussions with the staff of NASA GSFC, we arrived at an architecture that employs complete transmit/receive modules for each subarray. Amplitude and phase control at each of the transmit modules will allow a low-sidelobe transmit pattern to be generated over scan angles of +/- 50 degrees. Each receiver module will include all electronics necessary to downconvert the received signal to an IF offset of 30 MHz where it will be digitized for further processing.

A faculty development program integrating cross-cultural care into a gastrointestinal pathophysiology tutorial benefits students, tutors, and the course.

PubMed

Shields, Helen M; Leffler, Daniel A; Peters, Antoinette S; Llerena-Quinn, Roxana; Nambudiri, Vinod E; White, Augustus A; Hayward, Jane N; Pelletier, Stephen R

2015-06-01

A specific faculty development program for tutors to teach cross-cultural care in a preclinical gastrointestinal pathophysiology course with weekly longitudinal followup sessions was designed in 2007 and conducted in the same manner over a 6-yr period. Anonymous student evaluations of how "frequently" the course and the tutor were actively teaching cross-cultural care were performed. The statements "This tutor actively teaches culturally competent care" and "Issues of culture and ethnicity were addressed" were significantly improved over baseline 2004 data. These increases were sustained over the 6-yr period. A tutor's overall rating as a teacher was moderately correlated with his/her "frequently" actively teaching cross-cultural care (r = 0.385, P < 0. 001). Course evaluation scores were excellent and put the course into the group of preclinical courses with the top ratings. Students in the Race in Curriculum Group asked that the program be expanded to other preclinical courses. In conclusion, from 2007 to 2012, a faculty development program for teaching cross-cultural care consistently increased the discussion of cross-cultural care in the tutorial and course over each year beginning with 2007 compared with the baseline year of 2004. Our data suggest that cross-cultural care can be effectively integrated into pathophysiology tutorials and helps improve students' satisfaction and tutors' ratings. Teaching cross-cultural care in a pathophysiology tutorial did not detract from the course's overall evaluations, which remained in the top group over the 6-yr period. Copyright © 2015 The American Physiological Society.

Effect of ice massage on lower extremity functional performance and weight discrimination ability in collegiate footballers.

PubMed

Sharma, Geeta; Noohu, Majumi Mohamad

2014-09-01

Cryotherapy, in the form of ice massge is used to reduce inflammation after acute musculoskeletal injury or trauma. The potential negative effects of ice massage on proprioception are unknown, despite equivocal evidence supporting its effectiveness. The purpose of the study was to test the influence of cooling on weight discrimination ability and hence the performance in footballers. The study was of same subject experimental design (pretest-posttest design). Thirty male collegiate football players, whose mean age was 21.07 years, participated in the study. The participants were assessed for two functional performance tests, single leg hop test and crossed over hop test and weight discrimination ability before and after ice massage for 5 minutes on hamstrings muscle tendon. Pre cooling scores of Single Leg Hop Test of the dominant leg in the subjects was 166.65 (± 10.16) cm and post cooling scores of the dominant leg was 167.25 (± 11.77) cm. Pre cooling scores of Crossed Over Hop Test of the dominant leg in the subjects was 174.14 (± 8.60) cm and post cooling scores of the dominant leg was 174.45 (± 9.28) cm. Pre cooling scores of Weight Discrimination Differential Threshold of the dominant leg in the subjects was 1.625 ± 1.179 kg compared with post cooling scores of the dominant leg 1.85 (± 1.91) kg. Pre cooling scores of single leg hop and crossed over hop test of the dominant leg in the subjects compared with post cooling scores of the dominant leg showed no significant differences and it was also noted that the weight discrimination ability (weight discrimination differential threshold) didn't show any significant difference. All the values are reported as mean ± SD. This study provides additional evidence that proprioceptive acuity in the hamstring muscles (biceps femoris) remains largely unaffected after ice application to the hamstrings tendon (biceps femoris).

Information content of household-stratified epidemics.

PubMed

Kinyanjui, T M; Pellis, L; House, T

2016-09-01

Household structure is a key driver of many infectious diseases, as well as a natural target for interventions such as vaccination programs. Many theoretical and conceptual advances on household-stratified epidemic models are relatively recent, but have successfully managed to increase the applicability of such models to practical problems. To be of maximum realism and hence benefit, they require parameterisation from epidemiological data, and while household-stratified final size data has been the traditional source, increasingly time-series infection data from households are becoming available. This paper is concerned with the design of studies aimed at collecting time-series epidemic data in order to maximize the amount of information available to calibrate household models. A design decision involves a trade-off between the number of households to enrol and the sampling frequency. Two commonly used epidemiological study designs are considered: cross-sectional, where different households are sampled at every time point, and cohort, where the same households are followed over the course of the study period. The search for an optimal design uses Bayesian computationally intensive methods to explore the joint parameter-design space combined with the Shannon entropy of the posteriors to estimate the amount of information in each design. For the cross-sectional design, the amount of information increases with the sampling intensity, i.e., the designs with the highest number of time points have the most information. On the other hand, the cohort design often exhibits a trade-off between the number of households sampled and the intensity of follow-up. Our results broadly support the choices made in existing epidemiological data collection studies. Prospective problem-specific use of our computational methods can bring significant benefits in guiding future study designs. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Shoulder Injuries in Individuals Who Participate in CrossFit Training

PubMed Central

Summitt, Ryan J.; Cotton, Ryan A.; Kays, Adam C.; Slaven, Emily J.

2016-01-01

Background: CrossFit, a sport and fitness program, has become increasingly popular both nationally and internationally. Researchers have recently identified significant improvements in health and wellness due to CrossFit. However, some individuals assert that CrossFit poses an inherent risk of injury, specifically to the shoulder, due to the intensity of training. Currently, there is limited evidence to support this assertion. Hypothesis: Exercises performed during CrossFit do not place the shoulder at greater risk for injury. Injury rates are comparable to other sports of similar intensity. Study Design: Descriptive survey study. Level of Evidence: Level 5. Methods: An electronic survey was developed and dispersed to approximately 980 individuals who trained in CrossFit gyms. The survey identified demographic data, training characteristics, and the prevalence of injury over a 6-month period in individuals who participated in CrossFit training. Results: A total of 187 (19.1%) individuals completed the survey. Forty-four (23.5%) indicated that they had experienced a shoulder injury during CrossFit training over the previous 6 months. Of those who reported injury, 17 (38.6%) stated that this injury was an exacerbation of a previous injury sustained prior to starting CrossFit. There was no significant relationship between several demographic and training variables and shoulder injury. All shoulder injuries occurred at a rate of 1.94 per 1000 hours training, while “new” shoulder injuries occurred at a rate of 1.18 per 1000 hours training. The most commonly attributed causes of injury were improper form (33.3%) and exacerbation of a previous injury (33.3%). Twenty-five (64.1%) of those who experienced injury reported 1 month or less of training reduction due to the injury. Conclusion: Shoulder injury rates during CrossFit training are comparable to other methods of recreational exercise. Clinical Relevance: Clinicians should be aware of training demands of exercises in CrossFit and modifications for these exercises to safely progress their patients back to participation. PMID:27578854

How are parent–child conflict and childhood externalizing symptoms related over time? Results from a genetically informative cross-lagged study

PubMed Central

BURT, S. ALEXANDRA; McGUE, MATT; KRUEGER, ROBERT F.; IACONO, WILLIAM G.

2008-01-01

The present study attempted to determine the direction and etiology of the robust relationship between childhood externalizing (EXT) symptoms and parent–child conflict using a genetically informative longitudinal model and data from the ongoing Minnesota Twin Family Study. Participants consisted of 1,506 same-sex twins assessed at ages 11 and 14, and their parents. The relationship between EXT and parent–child conflict from ages 11 to 14 was examined within a biometrical cross-lagged design. The results revealed three primary findings: first, the stability of conflict and externalizing over time is largely, although not solely, a result of genetic factors. Second, there appears to be a bidirectional relationship between conflict and EXT over time, such that both conflict and EXT at 11 independently predict the other 3 years later. Finally, the results are consistent with the notion that parent–child conflict partially results from parental responses to their child’s heritable externalizing behavior, while simultaneously contributing to child externalizing via environmental mechanisms. These results suggest a “downward spiral” of interplay between parent–child conflict and EXT, and offer confirmation of a (partially) environmentally mediated effect of parenting on child behavior. PMID:15971764

Design study of beam position monitors for measuring second-order moments of charged particle beams

NASA Astrophysics Data System (ADS)

Yanagida, Kenichi; Suzuki, Shinsuke; Hanaki, Hirofumi

2012-01-01

This paper presents a theoretical investigation on the multipole moments of charged particle beams in two-dimensional polar coordinates. The theoretical description of multipole moments is based on a single-particle system that is expanded to a multiparticle system by superposition, i.e., summing over all single-particle results. This paper also presents an analysis and design method for a beam position monitor (BPM) that detects higher-order (multipole) moments of a charged particle beam. To calculate the electric fields, a numerical analysis based on the finite difference method was created and carried out. Validity of the numerical analysis was proven by comparing the numerical with the analytical results for a BPM with circular cross section. Six-electrode BPMs with circular and elliptical cross sections were designed for the SPring-8 linac. The results of the numerical calculations show that the second-order moment can be detected for beam sizes ≧420μm (circular) and ≧550μm (elliptical).

Low-Power Architectures for Large Radio Astronomy Correlators

NASA Technical Reports Server (NTRS)

D'Addario, Larry R.

2011-01-01

The architecture of a cross-correlator for a synthesis radio telescope with N greater than 1000 antennas is studied with the objective of minimizing power consumption. It is found that the optimum architecture minimizes memory operations, and this implies preference for a matrix structure over a pipeline structure and avoiding the use of memory banks as accumulation registers when sharing multiply-accumulators among baselines. A straw-man design for N = 2000 and bandwidth of 1 GHz, based on ASICs fabricated in a 90 nm CMOS process, is presented. The cross-correlator proper (excluding per-antenna processing) is estimated to consume less than 35 kW.

[The case-case-time-control study design].

PubMed

Wang, Jing; Zhuo, Lin; Zhan, Siyan

2014-12-01

Although the 'self-matched case-only studies' (such as the case-cross-over or self-controlled case-series method) can control the time-invariant confounders (measured or unmeasured) through design of the study, however, they can not control those confounders that vary with time. A bidirectional case-crossover design can be used to adjust the exposure-time trends. In the areas of pharmaco-epidemiology, illness often influence the future use of medications, making a bidirectional study design problematic. Suissa's case-time-control design combines the case-crossover and the case-control design which could adjust for exposure-trend bias, but the control group may reintroduce selection bias, if the matching does not go well. We propose a "case-case-time-control" design which is an extension of the case-time-control design. However, rather than using a sample of external controls, we choose those future cases as controls for current cases to counter the bias that arising from temporal trends caused by exposure to the target of interest. In the end of this article we will discuss the strength and limitations of this design based on an applied example.

Cross-border-assisted reproduction: a qualitative account of UK travellers' experiences.

PubMed

Hudson, Nicky; Culley, Lorraine; Blyth, Eric; Norton, Wendy; Pacey, Allan; Rapport, Frances

2016-06-01

Surveys on patients' experiences of cross-border fertility treatment have reported a range of positive and challenging features. However, the number of such studies is limited, and there is no detailed qualitative account of the experiences of UK patients who travel overseas for fertility treatment. The present study used a cross-sectional, qualitative design and in-depth interviews. Fifty-one participants (41 women and 10 men, representing 41 treatment 'cases') participated in semi-structured interviews. The experiences reported were broadly positive with a large proportion of participants (39 cases, 95%) citing a favourable overall experience with only two cases (5%) reporting a more negative experience. Thematic analysis revealed 6 major categories and 20 sub-categories, which described the positive and challenging aspects of cross-border fertility travel. The positive aspects were represented by the categories: 'access', 'control' and 'care and respect'. The more challenging aspects were categorized as 'logistics and coordination of care', 'uncertainty' and 'cultural dissonance'. The study confirms findings from others that despite some challenges, there is a relatively high level of patient satisfaction with cross-border treatment with participants able to extend the boundaries of their fertility-seeking trajectories and in some cases, regain a sense of control over their treatment.

Rationale, design, and methods for process evaluation in the Childhood Obesity Research Demonstration project

USDA-ARS?s Scientific Manuscript database

The cross-site process evaluation plan for the Childhood Obesity Research Demonstration (CORD) project is described here. The CORD project comprises 3 unique demonstration projects designed to integrate multi-level, multi-setting health care and public health interventions over a 4-year funding peri...

Fuel treatment effects on soil chemistry and foliar physiology of three coniferous species at the Teakettle Experimental Forest, California, USA

Treesearch

Rakesh Minocha; Swathi A. Turlapati; Stephanie Long; Malcolm North

2013-01-01

A full factorial design crossing overstory (O) and understory (U) thinning and prescribed burning (B) was started at Teakettle Experimental Forest, California, in 2001 with the aim of achieving shifts in species composition to favor fire-resistant pines over fir. The goal of the present study was to evaluate the use of metabolic changes as early indicators for...

Effect of intravenous or oral sodium chlorate administration on the fecal shedding of Escherichia coli in sheep

USDA-ARS?s Scientific Manuscript database

The effect of gavage or intravenous (i.v.) administration of sodium chlorate salts on the fecal shedding of generic Escherichia coli in wether lambs was studied. To this end, 9 lambs (27 +/- 2.5 kg) were administered 150 mg NaClO3 per kg BW by gavage or i.v. infusion in a cross-over design with sal...

Prolonged remission from hepatic encephalopathy with rifaximin: results of a placebo crossover analysis

PubMed Central

Bajaj, J S; Barrett, A C; Bortey, E; Paterson, C; Forbes, W P

2015-01-01

Background Rifaximin therapy reduced risk of hepatic encephalopathy (HE) recurrence and HE-related hospitalisations during a 6-month, randomised, placebo-controlled trial (RCT) and a 24-month open-label maintenance (OLM) study. However, the impact of crossover from placebo to rifaximin therapy is unclear. Aim To study the impact of crossing over from placebo to rifaximin treatment on breakthrough HE and hospitalisation rates using a within-subjects design. Methods Adults with cirrhosis and history of overt HE episodes, currently in HE remission, received placebo during the RCT and crossed over to rifaximin 550 mg twice daily during the OLM study. Rate of breakthrough overt HE episodes, hospitalisations and incidence and rate of adverse events (AEs) were analysed during RCT and first 6 months of OLM. Results Of 82 patients randomised to placebo in the RCT who crossed over to the OLM study, 39 experienced an HE episode during the RCT compared with 14 during the OLM study (P < 0.0001). Significantly lower rates of HE events were observed with rifaximin treatment compared with placebo treatment (P < 0.0001). Rates of HE-related hospitalisation were numerically lower during rifaximin treatment compared with placebo treatment, although not significant. Rates of most common AEs, serious AEs and infection-related AEs were similar between the two treatments. Conclusions This analysis confirms the repeatability of results from the RCT on safety and efficacy of rifaximin 550 mg twice daily in reducing the risk of hepatic encephalopathy recurrence, and suggests these findings are translatable outside of a rigorous, controlled trial setting. PMID:25339518

Control of Stationary Cross-Flow Modes in a Mach 3.5 Boundary Layer Using Patterned Passive and Active Roughness

NASA Technical Reports Server (NTRS)

Schuele, Chan Yong

2011-01-01

Spanwise-periodic roughness designed to excite selected wavelengths of stationary cross- ow modes was investigated in a 3-D boundary layer at Mach 3.5. The test model was a sharp-tipped 14deg right-circular cone. The model and integrated sensor traversing system were placed in the Mach 3.5 Supersonic Low Disturbance Tunnel (SLDT) equipped with a "quiet design" nozzle at the NASA Langley Research Center. The model was oriented at a 4:2deg angle of attack to produce a mean cross-fl ow velocity component in the boundary layer over the cone. Five removable cone tips have been investigated. One has a smooth surface that is used to document the baseline ("natural") conditions. Two had minute (20 - 40 micron) "dimples" that are equally spaced around the circumference, at a streamwise location that is just upstream of the linear stability neutral growth branch for cross- ow modes. The azimuthal mode numbers of the dimpled tips were selected to either enhance the most amplified wave numbers, or to suppress the growth of the most amplified wave numbers. Two of the cone tips had an array of plasma streamwise vortex generators that were designed to simulate the disturbances produced by the passive patterned roughness. The results indicate that the stationary cross-fl ow modes were highly receptive to the patterned roughness of both passive and active types. The patterned passive roughness that was designed to suppress the growth of the most amplified modes had an azimuthal wavelength that was 66% smaller that that of the most amplified stationary cross- ow mode. This had the effect to increase the transition Reynolds number from 25% to 50% depending on the measurement technique. The application of the research is on turbulent transition control on swept wings of supersonic aircraft. The plasma-based roughness has the advantage over the passive roughness of being able to be adaptable to different conditions that would occur during a flight mission.

Defining and Estimating Healthy Aging in Spain: A Cross-sectional Study.

PubMed

Rodriguez-Laso, Angel; McLaughlin, Sara J; Urdaneta, Elena; Yanguas, Javier

2018-03-19

Using an operational continuum of healthy aging developed by U.S. researchers, we sought to estimate the prevalence of healthy aging among older Spaniards, inform the development of a definition of healthy aging in Spain, and foster cross-national research on healthy aging. The ELES pilot study is a nationwide, cross-sectional survey of community-dwelling Spaniards 50 years and older. The prevalence of healthy aging was calculated for the 65 and over population using varying definitions. To evaluate their validity, we examined the association of healthy aging with the 8 foot up & go test, quality of life scores and self-perceived health using multiple linear and logistic regression. The estimated prevalence of healthy aging varied across the operational continuum, from 4.5% to 49.2%. Prevalence figures were greater for men and those aged 65 to 79 years and were higher than in the United States. Predicted mean physical performance scores were similar for 3 of the 4 definitions, suggesting that stringent definitions of healthy aging offer little advantage over a more moderate one. Similar to U.S. researchers, we recommend a definition of healthy aging that incorporates measures of functional health and limiting disease as opposed to definitions requiring the absence of all disease in studies designed to assess the effect of policy initiatives on healthy aging.

A Faculty Development Program Integrating Cross-Cultural Care into a Gastrointestinal Pathophysiology Tutorial Benefits Students, Tutors, and the Course

ERIC Educational Resources Information Center

Shields, Helen M.; Leffler, Daniel A.; Peters, Antoinette S.; Llerena-Quinn, Roxana; Nambudiri, Vinod E.; White, Augustus A., III; Hayward, Jane N.; Pelletier, Stephen R.

2015-01-01

A specific faculty development program for tutors to teach cross-cultural care in a preclinical gastrointestinal pathophysiology course with weekly longitudinal followup sessions was designed in 2007 and conducted in the same manner over a 6-yr period. Anonymous student evaluations of how "frequently" the course and the tutor were…

Pixelated Checkerboard Metasurface for Ultra-Wideband Radar Cross Section Reduction.

PubMed

Haji-Ahmadi, Mohammad-Javad; Nayyeri, Vahid; Soleimani, Mohammad; Ramahi, Omar M

2017-09-12

In this paper we designed and fabricated a metasurface working as a radar cross section (RCS) reducer over an ultra wide band of frequency from 3.8 to 10.7 GHz. The designed metasurface is a chessboard-like surface made of alternating tiles, with each tile composed of identical unit cells. We develop a novel, simple, highly robust and fully automated approach for designing the unit cells. First, a topology optimization algorithm is used to engineer the shape of the two unit cells. The area of each unit cell is pixelated. A particle swarm optimization algorithm is applied wherein each pixel corresponds to a bit having a binary value of 1 or 0 indicating metallization or no metallization. With the objective of reducing the RCS over a specified frequency range, the optimization algorithm is then linked to a full wave three-dimensional electromagnetic simulator. To validate the design procedure, a surface was designed, fabricated and experimentally tested showing significantly enhanced performance than previous works. Additionally, angular analysis is also presented showing good stability and wide-angle behavior of the designed RCS reducer. The automated design procedure has a wide range of applications and can be easily extended to design surfaces for antennas, energy harvesters, noise mitigation in electronic circuit boards amongst others.

Multiple social identifications and adolescents' self-esteem.

PubMed

Benish-Weisman, Maya; Daniel, Ella; Schiefer, David; Möllering, Anna; Knafo-Noam, Ariel

2015-10-01

The research examined the relationship between multiple social identifications and self-esteem. Early adolescents (M = 11.4, SD = .95) and mid-adolescents (M = 15.9, SD = 1.18) from Germany and Israel (n = 2337) were studied. Respondents described their social identification as students, family members, and as members of the majority national group and reported self-esteem. A longitudinal, cross-sectional and cross-cultural design revealed, as predicted, multiple social identifications related positively to self-esteem concurrently; they also related positively to self-esteem longitudinally over the course of a year. Moreover, multiple social identifications were found to be antecedent to self-esteem, not vice versa. Finally, multiple social identifications were found to decrease over time. The article discusses the contribution of multiple social identifications to self-esteem at different ages and in various contexts. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Repeated Cross-Sectional Assessment of Commercial Truck Driver Health.

PubMed

Thiese, Matthew S; Moffitt, Gary; Hanowski, Richard J; Kales, Stefanos N; Porter, Richard J; Hegmann, Kurt T

2015-09-01

To assess relationships and trends over time in individual conditions and multiple conditions among a large sample of independent, nonoverlapping truck drivers using a repeated cross-sectional study design. Commercial driver medical examinations were conducted on 95,567 commercial drivers between January 1, 2005, and October 31, 2012. Specific medical conditions that have been identified by the Federal Motor Carrier Safety Administration's Medical Review Board as possibly increasing crash risk were examined. Prevalence and trends over time were analyzed. A total of 8 of the 13 conditions significantly increased from 2005 to 2012. Prevalence of multiple concomitant conditions also increased, with prevalence odds ratios as high as 7.39 (95% confidence interval, 3.92 to 13.98) for four or more conditions in 2012 as compared with 2005. Individual and multiple conditions thought to be associated with increased crash risk significantly increased between 2005 and 2012.

Accelerated longitudinal designs: An overview of modelling, power, costs and handling missing data.

PubMed

Galbraith, Sally; Bowden, Jack; Mander, Adrian

2017-02-01

Longitudinal studies are often used to investigate age-related developmental change. Whereas a single cohort design takes a group of individuals at the same initial age and follows them over time, an accelerated longitudinal design takes multiple single cohorts, each one starting at a different age. The main advantage of an accelerated longitudinal design is its ability to span the age range of interest in a shorter period of time than would be possible with a single cohort longitudinal design. This paper considers design issues for accelerated longitudinal studies. A linear mixed effect model is considered to describe the responses over age with random effects for intercept and slope parameters. Random and fixed cohort effects are used to cope with the potential bias accelerated longitudinal designs have due to multiple cohorts. The impact of other factors such as costs and the impact of dropouts on the power of testing or the precision of estimating parameters are examined. As duration-related costs increase relative to recruitment costs the best designs shift towards shorter duration and eventually cross-sectional design being best. For designs with the same duration but differing interval between measurements, we found there was a cutoff point for measurement costs relative to recruitment costs relating to frequency of measurements. Under our model of 30% dropout there was a maximum power loss of 7%.

An experimental study of stratospheric gravity waves - Design and preliminary results

NASA Astrophysics Data System (ADS)

Talagrand, O.; Ovarlez, H.

1984-02-01

The design of balloon-borne experimental apparatus for long-term gravitational-wave measurements in the stratosphere is reported, and preliminary results of a first test flight are presented. Two gondolas (each containing a pressure sensor; a temperature sensor; horizontal and vertical sonic anemometers; a fin equipped with crossed magnetometers; and data-processing, data-transmission, and control electronics) are suspended 100 and 300 m below a solar/terrestrial-IR-absorption-heated hot-air balloon drifting between altitudes 22 km (night) and 28 km (day); power is supplied by NiCd batteries recharged by solar cells. The path of the first flight, a circumnavigation beginning in Pretoria, South Africa and crossing South America and northern Australia, from December 11, 1982, to February 2, 1983 (when transmission ceased over southern Africa) is shown on a map, and sample data for a 36-h period are summarized in a graph.

Maize aflatoxin accumulation segregates with early maturing selections from an S2 breeding cross population.

PubMed

Henry, W Brien

2013-01-15

Maize breeders continue to seek new sources of aflatoxin resistance, but most lines identified as resistance sources are late maturing. The vast difference in flowering time makes it hard to cross these lines with proprietary commercial lines that mature much earlier and often subjects the reproductive phase of these resistant lines to the hottest and driest portion of the summer, making silking, pollination and grain fill challenging. Two hundred crosses from the GEM Project were screened for aflatoxin accumulation at Mississippi State in 2008, and a subset of these lines were screened again in 2009. The breeding cross UR13085:S99g99u was identified as a potential source of aflatoxin resistance, and maturity-based selections were made from an S2 breeding population from this same germplasm source: UR13085:S99g99u-B-B. The earliest maturing selections performed poorly for aflatoxin accumulation, but later maturing selections were identified with favorable levels of aflatoxin accumulation. These selections, while designated as "late" within this study, matured earlier than most aflatoxin resistant lines presently available to breeders. Two selections from this study, designated S5_L7 and S5_L8, are potential sources of aflatoxin resistance and will be advanced for line development and additional aflatoxin screening over more site years and environments.

Non-traditional shape GFRP rebars for concrete reinforcement

NASA Astrophysics Data System (ADS)

Claure, Guillermo G.

The use of glass-fiber-reinforced-polymer (GFRP) composites as internal reinforcement (rebars) for concrete structures has proven to be an alternative to traditional steel reinforcement due to significant advantages such as magnetic transparency and, most importantly, corrosion resistance equating to durability and structural life extension. In recent years, the number of projects specifying GFRP reinforcement has increased dramatically leading the construction industry towards more sustainable practices. Typically, GFRP rebars are similar to their steel counterparts having external deformations or surface enhancements designed to develop bond to concrete, as well as having solid circular cross-sections; but lately, the worldwide composites industry has taken advantage of the pultrusion process developing GFRP rebars with non-traditional cross-sectional shapes destined to optimize their mechanical, physical, and environmental attributes. Recently, circular GFRP rebars with a hollow-core have also become available. They offer advantages such as a larger surface area for improved bond, and the use of the effective cross-sectional area that is engaged to carry load since fibers at the center of a solid cross-section are generally not fully engaged. For a complete understanding of GFRP rebar physical properties, a study on material characterization regarding a quantitative cross-sectional area analysis of different GFRP rebars was undertaken with a sample population of 190 GFRP specimens with rebar denomination ranging from #2 to #6 and with different cross-sectional shapes and surface deformations manufactured by five pultruders from around the world. The water displacement method was applied as a feasible and reliable way to conduct the investigation. In addition to developing a repeatable protocol for measuring cross-sectional area, the objectives of establishing critical statistical information related to the test methodology and recommending improvements to existing provisions and standards allowing for a consistent universal norm for all GFRP rebars were reached. This dissertation also presents an evaluation of the structural behavior of reinforced concrete (RC) beams and slabs using the new type of GFRP rebar consisting of a non-traditional hollow-core shape compared to "traditional" solid round rebars with equivalent cross-sectional areas within the framework of two studies, respectively. To validate the design assumptions following ACI 440.1R design guidelines, two conditions were investigated: under-reinforced (failure controlled by rupture of GFRP rebar); and, over-reinforced (failure controlled by crushing of concrete). For comparison, a cyclic three-point bending load test matrix was developed: for beams, 3 under-reinforced and 3 over-reinforced with hollow-core and solid GFRP rebars, respectively, making a total of 12 RC specimens; for slabs, 3 under-reinforced and 3 over-reinforced with hollow-core and 2 types of solid GFRP rebars, respectively, making a total of 18 RC slabs. The studies on GFRP RC beams and slabs concluded that the hollow-core GFRP rebars were as effective as their solid counterpart and ACI 440.1R design guidelines were applicable to predict their performance. It was shown that final design may be controlled by the permissible deflections as governing parameter for elements under service conditions. Also, a final study with a test matrix containing six extra specimens was generated for post-fire residual strength evaluation of fire-exposed GFRP RC slabs along with temperature gradient in the slabs and dynamic mechanical analysis (DMA) investigation on GFRP samples extracted from the fire-exposed slabs. In this study, the ability of GFRP RC slabs to retain structural integrity during a standards fire exposure as well as determining the residual structural capacity were investigated. The residual strength evaluation of the fire-exposed slabs showed a range of results varying between +/- 10%, of the virgin slabs. And, 19 mm (0.75 in.) cover with normal weight concrete was shown to be adequate to provide the necessary fire protection to the GFRP rebars preventing irreversible damage for two-hour fire rated GFRP RC slabs subjected to service loads; also, from the DMA and glass transition temperature of samples extracted from the GFRP rebars, it is inferred that the resin had undergone a post curing phase.

An optimal structure for a 34-meter millimeter-wave center-fed BWG antenna: The Cross-Box concept

NASA Technical Reports Server (NTRS)

Chuang, K. L.

1988-01-01

An approach to the design of the planned NASA/JPL 34 m elevation-over-azimuth (Az-El) antenna structure at the Venus site (DSS-13) is presented. The antenna structural configuration accommodates a large (2.44 m) beam waveguide (BWG) tube centrally routed through the reflector-alidade structure, an elevation wheel design, and an optimal structural geometry. The design encompasses a cross-box elevation wheel-reflector base substructure that preserves homology while satisfying many constraints, such as structure weight, surface tolerance, stresses, natural frequency, and various functional constraints. The functional requirements are set to ensure that microwave performance at millimeter wavelengths is adequate. The cross-box configuration was modeled, optimized, and found to satisfy all DSN HEF baseline antenna specifications. In addition, the structure design was conceptualized and analyzed with an emphasis on preserving the structure envelope and keeping modifications relative to the HEF antennas to a minimum, thus enabling the transferability of the BWG technology for future retrofitting. Good performance results were obtained.

Effects of Subsensory Noise and Fatigue on Knee Landing and Cross-over Cutting Biomechanics in Male Athletes.

PubMed

Qu, Xingda; Jiang, Jianxin; Hu, Xinyao

2018-06-01

The objective of this study was to examine the effects of subsensory noise and fatigue on knee biomechanics during the athletic task of landing followed by cross-over cutting. A total of 32 healthy male athletes participated in the study. They were evenly divided into 2 groups: no fatigue group and fatigue group. Fatigue was induced to the lower extremity by a repetitive squatting exercise in the fatigue group. Subsensory noise was generated by linear miniature vibrators bilaterally placed around the knee joints. During data collection, the participants were instructed to perform landing followed by cross-over cutting in both the subsensory on and off conditions. Dependent variables were selected to assess knee biomechanics in the phases of landing and cross-over cutting, separately. Results showed that fatigue resulted in larger knee flexion during landing and larger knee internal rotation during cross-over cutting. Subsensory noise was found to reduce knee rotation impulse during cross-over cutting. These findings suggest that cross-over cutting is more dangerous than landing in the fatigue condition, and subsensory noise may lead to changes in knee biomechanics consistent with reduced risk of anterior cruciate ligament injuries, but the changes may be task-specific.

Mule deer passage beneath an overland coal conveyor

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

Greenwood, C.L.; Dalton, L.B.

1984-07-31

Presently, information pertaining to migration and daily movement patterns of big game in relation to overland conveyors or large diameter pipelines is sparse. A literature review showed that moose, caribou, reindeer, and dall sheep will pass beneath or over large diameter pipeline systems. But no information was found relative to big game crossing coal conveyor systems. Mule deer passage beneath an overland coal conveyor in Carbon County, Utah, was studied during spring 1981. Deer avoided crossing at underpass opportunities where the clearance was less than 50 cm. Clearances between 50 and 90 cm were selected for crossing. Deer passed beneathmore » the conveyor during day and nighttime conditions and while the conveyor was either operating or idle. Recommendations are discussed for designing conveyors and pipelines to facilitate big game passage. 13 references, 2 tables.« less

Identifying Complex Cultural Interactions in the Instructional Design Process: A Case Study of a Cross-Border, Cross-Sector Training for Innovation Program

ERIC Educational Resources Information Center

Russell, L. Roxanne; Kinuthia, Wanjira L.; Lokey-Vega, Anissa; Tsang-Kosma, Winnie; Madathany, Reeny

2013-01-01

The purpose of this research is to identify complex cultural dynamics in the instructional design process of a cross-sector, cross-border training environment by applying Young's (2009) Culture-Based Model (CBM) as a theoretical framework and taxonomy for description of the instructional design process under the conditions of one case. This…

A meta-analysis on progressive atrophy in intractable temporal lobe epilepsy

PubMed Central

Caciagli, Lorenzo; Bernasconi, Andrea; Wiebe, Samuel; Koepp, Matthias J.; Bernasconi, Neda

2017-01-01

Objective: It remains unclear whether drug-resistant temporal lobe epilepsy (TLE) is associated with cumulative brain damage, with no expert consensus and no quantitative syntheses of the available evidence. Methods: We conducted a systematic review and meta-analysis of MRI studies on progressive atrophy, searching PubMed and Ovid MEDLINE databases for cross-sectional and longitudinal quantitative MRI studies on drug-resistant TLE. Results: We screened 2,976 records and assessed eligibility of 248 full-text articles. Forty-two articles met the inclusion criteria for quantitative evaluation. We observed a predominance of cross-sectional studies, use of different clinical indices of progression, and high heterogeneity in age-control procedures. Meta-analysis of 18/1 cross-sectional/longitudinal studies on hippocampal atrophy (n = 979 patients) yielded a pooled effect size of r = −0.42 for ipsilateral atrophy related to epilepsy duration (95% confidence interval [CI] −0.51 to −0.32; p < 0.0001; I2 = 65.22%) and r = −0.35 related to seizure frequency (95% CI −0.47 to −0.22; p < 0.0001; I2 = 61.97%). Sensitivity analyses did not change the results. Narrative synthesis of 25/3 cross-sectional/longitudinal studies on whole brain atrophy (n = 1,504 patients) indicated that >80% of articles reported duration-related progression in extratemporal cortical and subcortical regions. Detailed analysis of study design features yielded low to moderate levels of evidence for progressive atrophy across studies, mainly due to dominance of cross-sectional over longitudinal investigations, use of diverse measures of seizure estimates, and absence of consistent age control procedures. Conclusions: While the neuroimaging literature is overall suggestive of progressive atrophy in drug-resistant TLE, published studies have employed rather weak designs to directly demonstrate it. Longitudinal multicohort studies are needed to unequivocally differentiate aging from disease progression. PMID:28687722

A prospective randomised cross-over study of the effect of insulin analogues and human insulin on the frequency of severe hypoglycaemia in patients with type 1 diabetes and recurrent hypoglycaemia (the HypoAna trial): study rationale and design

PubMed Central

2012-01-01

Background Severe hypoglycaemia still represents a significant problem in insulin-treated diabetes. Most patients do not experience severe hypoglycaemia often. However, 20% of patients with type 1 diabetes experience recurrent severe hypoglycaemia corresponding to at least two episodes per year. The effect of insulin analogues on glycaemic control has been documented in large trials, while their effect on the frequency of severe hypoglycaemia is less clear, especially in patients with recurrent severe hypoglycaemia. The HypoAna Trial is designed to investigate whether short-acting and long-acting insulin analogues in comparison with human insulin are superior in reducing the occurrence of severe hypoglycaemic episodes in patients with recurrent hypoglycaemia. This paper reports the study design of the HypoAna Trial. Methods/design The study is a Danish two-year investigator-initiated, prospective, randomised, open, blinded endpoint (PROBE), multicentre, cross-over trial investigating the effect of insulin analogues versus human insulin on the frequency of severe hypoglycaemia in subjects with type 1 diabetes. Patients are randomised to treatment with basal-bolus therapy with insulin detemir / insulin aspart or human NPH insulin / human regular insulin in random order. The major inclusion criterion is history of two or more episodes of severe hypoglycaemia in the preceding year. Discussion In contrast to almost all other studies in this field the HypoAna Trial includes only patients with major problems with hypoglycaemia. The HypoAna Trial will elucidate whether basal-bolus regimen with short-acting and long-acting insulin analogues in comparison with human insulin are superior in reducing occurrence of severe hypoglycaemic episodes in hypoglycaemia prone patients with type 1 diabetes. http://www.clinicaltrials.gov: NCT00346996. PMID:22727048

Effectiveness of a vegetable dental chew on periodontal disease parameters in toy breed dogs.

PubMed

Clarke, D E; Kelman, M; Perkins, N

2011-01-01

Sixteen toy breed dogs completed a parallel, 70-day two-period, cross-over design clinical study to determine the effect of a vegetable dental chew on gingivitis, halitosis, plaque, and calculus accumulations. The dogs were randomly assigned into two groups. During one study period the dogs were fed a non-dental dry diet only and during the second study period were fed the same dry diet supplemented by the daily addition of a vegetable dental chew. Daily administration of the dental chew was shown to reduce halitosis, as well as, significantly reduce gingivitis, plaque and calculus accumulation and therefore may play a significant role in the improvement of canine oral health over the long-term.

Design of a polarization-independent, wide-angle, broadband visible absorber

NASA Astrophysics Data System (ADS)

Jia, Xiuli; Wang, Xiaoou

2018-01-01

Many optical systems benefit from elements that can absorb a broad range of wavelengths over a wide range of angles, independent of polarization. In this paper, we present a polarization-independent, wide-angle, broadband absorber in the visible regime that exploits strong symmetric and asymmetric resonance modes of electromagnetic dipoles. It makes use of a bilayer cross-pattern structure which is simple, having five layers that include two stacks of metal ribbon in cross-patterns, two dielectric spacers and a metal reflecting layer. Simulations show that the design exhibits a significantly enhanced absorption property when compared to a device with a bilayer metal film structure or any other complex structure of cross-patterns that have no intersection angle. The maximum absorption efficiency of the device is 100% at resonances, and its absorption characteristics can be maintained over a wide range of angles of incidence - up to ± 60° - regardless of the incident polarization. This strategy can, in principle, be applied to other material systems and could be useful in diverse applications, including thermal emitters, photovoltaics and photodetectors.

Variables associated with sleep quality in chronic tension-type headache: A cross-sectional and longitudinal design.

PubMed

Benito-González, Elena; Palacios-Ceña, Maria; Fernández-Muñoz, Juan J; Castaldo, Matteo; Wang, Kelun; Catena, Antonella; Arendt-Nielsen, Lars; Fernández-de-Las-Peñas, César

2018-01-01

To investigate variables associated at baseline (cross-sectional design) and at one year (longitudinal design) with the quality of sleep in chronic tension-type headache (CTTH). One hundred and eighty (n = 180) and 135 individuals with CTTH participated in the cross-sectional and longitudinal design respectively. Clinical features were collected with a 4-weeks headache diary at baseline and one-year follow-up. Sleep quality was assessed at baseline and 1-year follow-up with the Pittsburgh Sleep Quality Index. Anxiety and depression (Hospital Anxiety and Depression Scale-HADS), burden of headache (Headache Disability Inventory-HDI), quality of life (SF-36 questionnaire), and pressure pain thresholds (PPTs) at trigeminal, extra-trigeminal and widespread area were assessed at baseline. Hierarchical regression analyses were conducted to determine the associations between variables at baseline and 1-year follow-up with sleep quality. At baseline positive correlations between sleep quality and headache intensity, headache frequency, headache duration, emotional and physical burden of headache and depression were observed. The regression analyses found that depression and emotional burden of headache explained 27.5% of the variance in sleep quality at baseline (r2 = .262; F = 23.72 P < .001). At one-year, sleep quality was significantly associated with baseline burden of headache, depression, widespread PPTs, vitality and mental health domains. Regression analyses revealed that vitality, PPT over the second metacarpal and PPT over the neck explained 30.0% of the variance of sleep quality at one-year (r2 = .269, F = 9.71, P < .001). It seems that sleep quality exhibits a complex interaction in individuals with CTTH since depression and the emotional burden were associated with sleep quality at baseline, but vitality and PPTs over extra-trigeminal areas were associated with the quality of sleep at one-year.

Cost model relationships between textile manufacturing processes and design details for transport fuselage elements

NASA Technical Reports Server (NTRS)

Metschan, Stephen L.; Wilden, Kurtis S.; Sharpless, Garrett C.; Andelman, Rich M.

1993-01-01

Textile manufacturing processes offer potential cost and weight advantages over traditional composite materials and processes for transport fuselage elements. In the current study, design cost modeling relationships between textile processes and element design details were developed. Such relationships are expected to help future aircraft designers to make timely decisions on the effect of design details and overall configurations on textile fabrication costs. The fundamental advantage of a design cost model is to insure that the element design is cost effective for the intended process. Trade studies on the effects of processing parameters also help to optimize the manufacturing steps for a particular structural element. Two methods of analyzing design detail/process cost relationships developed for the design cost model were pursued in the current study. The first makes use of existing databases and alternative cost modeling methods (e.g. detailed estimating). The second compares design cost model predictions with data collected during the fabrication of seven foot circumferential frames for ATCAS crown test panels. The process used in this case involves 2D dry braiding and resin transfer molding of curved 'J' cross section frame members having design details characteristic of the baseline ATCAS crown design.

Instructional Design for Cross-Cultural Online Collaboration: Grouping Strategies and Assignment Design

ERIC Educational Resources Information Center

Wang, Chun-Min

2011-01-01

The latest networking technologies have made it easier to provide authentic learning experiences for intercultural collaboration. However, more guidance about how to conduct a successful online, cross-cultural collaboration is needed. The purpose of this study was to investigate the instructional design for forming a cross-cultural group and…

Simple, empirical approach to predict neutron capture cross sections from nuclear masses

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

Couture, Aaron Joseph; Casten, Richard F.; Cakirli, R. B.

Here, neutron capture cross sections are essential to understanding the astrophysical s and r processes, the modeling of nuclear reactor design and performance, and for a wide variety of nuclear forensics applications. Often, cross sections are needed for nuclei where experimental measurements are difficult. Enormous effort, over many decades, has gone into attempting to develop sophisticated statistical reaction models to predict these cross sections. Such work has met with some success but is often unable to reproduce measured cross sections to better than 40%, and has limited predictive power, with predictions from different models rapidly differing by an order ofmore » magnitude a few nucleons from the last measurement.« less

Simple, empirical approach to predict neutron capture cross sections from nuclear masses

DOE PAGES

Couture, Aaron Joseph; Casten, Richard F.; Cakirli, R. B.

2017-12-20

Here, neutron capture cross sections are essential to understanding the astrophysical s and r processes, the modeling of nuclear reactor design and performance, and for a wide variety of nuclear forensics applications. Often, cross sections are needed for nuclei where experimental measurements are difficult. Enormous effort, over many decades, has gone into attempting to develop sophisticated statistical reaction models to predict these cross sections. Such work has met with some success but is often unable to reproduce measured cross sections to better than 40%, and has limited predictive power, with predictions from different models rapidly differing by an order ofmore » magnitude a few nucleons from the last measurement.« less

Assessing spatial coupling in complex population dynamics using mutual prediction and continuity statistics

USGS Publications Warehouse

Nichols, J.M.; Moniz, L.; Nichols, J.D.; Pecora, L.M.; Cooch, E.

2005-01-01

A number of important questions in ecology involve the possibility of interactions or ?coupling? among potential components of ecological systems. The basic question of whether two components are coupled (exhibit dynamical interdependence) is relevant to investigations of movement of animals over space, population regulation, food webs and trophic interactions, and is also useful in the design of monitoring programs. For example, in spatially extended systems, coupling among populations in different locations implies the existence of redundant information in the system and the possibility of exploiting this redundancy in the development of spatial sampling designs. One approach to the identification of coupling involves study of the purported mechanisms linking system components. Another approach is based on time series of two potential components of the same system and, in previous ecological work, has relied on linear cross-correlation analysis. Here we present two different attractor-based approaches, continuity and mutual prediction, for determining the degree to which two population time series (e.g., at different spatial locations) are coupled. Both approaches are demonstrated on a one-dimensional predator?prey model system exhibiting complex dynamics. Of particular interest is the spatial asymmetry introduced into the model as linearly declining resource for the prey over the domain of the spatial coordinate. Results from these approaches are then compared to the more standard cross-correlation analysis. In contrast to cross-correlation, both continuity and mutual prediction are clearly able to discern the asymmetry in the flow of information through this system.

Melatonin improves sleep in children with epilepsy: randomized, double-blind cross-over study

PubMed Central

Jain, Sejal V; Horn, Paul S; Simakajornboon, Narong; Beebe, Dean W; Holland, Katherine; Byars, Anna W; Glauser, Tracy A

2015-01-01

Objective Insomnia, especially maintenance insomnia is widely prevalent in epilepsy. Although melatonin is commonly used, limited data address its efficacy. We performed a randomized, double-blind, placebo-controlled, cross-over study to identify the effects of melatonin on sleep and seizure control in children with epilepsy. Methods Eleven pre-pubertal, developmentally normal children aged 6–11 years with epilepsy were randomized by software algorithm to receive placebo or 9 mg sustained release melatonin for 4 weeks, followed by a 1-week washout and 4-week crossover condition. The pharmacy performed blinding; patients, parents and study staff other than a statistician were blinded. Primary outcomes were sleep onset latency and wakefulness after sleep onset (WASO) measured on polysomnography. Secondary outcomes included seizure frequency, epileptiform spike density per hour of sleep on EEG and reaction time measures on psychomotor vigilance task. Statistical tests appropriate for cross-over designs were used for analysis. Results Data were analyzed from ten subjects who completed the study. Melatonin decreased sleep latency (Mean difference (MD): 11.4 min, p= 0.02) and WASO (MD 22 min, p=0.04) as compared to placebo. No worsening of spike density or seizure frequency was seen. Additionally, Slow-wave sleep duration and REM latency were increased with melatonin and REM sleep duration was decreased. These changes were statistically significant. Worsening of headache was noted in one subject with migraine on melatonin. Conclusion Sustained-release melatonin resulted in statistically significant decreases in sleep latency and WASO. No clear effects on seizures were observed but the study was too small to allow any conclusions to be drawn in this regard. PMID:25862116

Prolonged remission from hepatic encephalopathy with rifaximin: results of a placebo crossover analysis.

PubMed

Bajaj, J S; Barrett, A C; Bortey, E; Paterson, C; Forbes, W P

2015-01-01

Rifaximin therapy reduced risk of hepatic encephalopathy (HE) recurrence and HE-related hospitalisations during a 6-month, randomised, placebo-controlled trial (RCT) and a 24-month open-label maintenance (OLM) study. However, the impact of crossover from placebo to rifaximin therapy is unclear. To study the impact of crossing over from placebo to rifaximin treatment on breakthrough HE and hospitalisation rates using a within-subjects design. Adults with cirrhosis and history of overt HE episodes, currently in HE remission, received placebo during the RCT and crossed over to rifaximin 550 mg twice daily during the OLM study. Rate of breakthrough overt HE episodes, hospitalisations and incidence and rate of adverse events (AEs) were analysed during RCT and first 6 months of OLM. Of 82 patients randomised to placebo in the RCT who crossed over to the OLM study, 39 experienced an HE episode during the RCT compared with 14 during the OLM study (P < 0.0001). Significantly lower rates of HE events were observed with rifaximin treatment compared with placebo treatment (P < 0.0001). Rates of HE-related hospitalisation were numerically lower during rifaximin treatment compared with placebo treatment, although not significant. Rates of most common AEs, serious AEs and infection-related AEs were similar between the two treatments. This analysis confirms the repeatability of results from the RCT on safety and efficacy of rifaximin 550 mg twice daily in reducing the risk of hepatic encephalopathy recurrence, and suggests these findings are translatable outside of a rigorous, controlled trial setting. © 2014 The Authors. Alimentary Pharmacology & Therapeutics published by John Wiley & Sons Ltd.

Social and health outcomes following upgrades to a national housing standard: a multilevel analysis of a five-wave repeated cross-sectional survey.

PubMed

Poortinga, Wouter; Jones, Nikki; Lannon, Simon; Jenkins, Huw

2017-12-02

While existing research indicates that housing improvements are associated with health improvements, less is known about the wider social and health benefits of meeting national housing standards, as well as those of their specific constituent measures. This study evaluates the impacts of a managed housing upgrade programme through a repeated cross-sectional survey design. A five-wave repeated cross-sectional survey was conducted over a seven-year period from 2009 to 2016 (n = 2075; n = 2219; n = 2015; n = 1991; and n = 1709, respectively). The study followed a managed upgrade programme designed to meet a national social housing standard over an extended period. The data were analysed from a multilevel perspective to take account of the time-dependent nature of the observations and differences in socio-demographic composition. The installation of the majority of individual housing measures (new windows and doors; boilers; kitchens; bathrooms; electrics; loft insulation; and cavity/external wall insulation) were associated with improvements in several social (housing suitability, satisfaction, and quality; thermal comfort and household finances) and health (mental, respiratory and general health) outcomes; and analyses showed relationships between the number of measures installed and the total amount invested on the one hand and the social and health outcomes on the other. There were however a few exceptions. Most notably, the installation of cavity wall insulation was associated with poorer health outcomes, and did not lead to better social outcomes. Also, no association was found between the number of measures installed and respiratory health. The study suggests that substantial housing investments through a managed upgrade programme may result in better social and health outcomes, and that the size of the improvements are proportionate to the number of measures installed and amount invested. However, there may be risks associated with specific measures; and more attention is needed for mechanical ventilation when upgrading energy efficiency of houses through fabric work. In addition to providing new evidence regarding the wider social and health outcomes, the study provides an analytical approach to evaluate upgrade programmes that are delivered over multiple years.

Tamarind seed gum-hydrolyzed polymethacrylamide-g-gellan beads for extended release of diclofenac sodium using 32 full factorial design.

PubMed

Nandi, Gouranga; Nandi, Amit Kumar; Khan, Najim Sarif; Pal, Souvik; Dey, Sibasish

2018-07-15

Development of tamarind seed gum (TSG)-hydrolyzed polymethacrylamide-g-gellan (h-Pmaa-g-GG) composite beads for extended release of diclofenac sodium using 3 2 full factorial design is the main purpose of this study. The ratio of h-Pmaa-g-GG and TSG and concentration of cross-linker CaCl 2 were taken as independent factors with three different levels of each. Effects of polymer ratio and CaCl 2 on drug entrapment efficiency (DEE), drug release, bead size and swelling were investigated. Responses such as DEE and different drug release parameters were statistically analyzed by 3 2 full factorial design using Design-Expert software and finally the formulation factors were optimized to obtain USP-reference release profile. Drug release rate was found to decrease with decrease in the ratio of h-Pmaa-g-GG:TSG and increase in the concentration of Ca 2+ ions in cross-linking medium. The optimized formulation showed DEE of 93.25% and an extended drug release profile over a period of 10h with f 2 =80.13. Kinetic modeling unveiled case-I-Fickian diffusion based drug release mechanism. Copyright © 2018 Elsevier B.V. All rights reserved.

Results From a Channel Restoration Project: Hydraulic Design Considerations

USGS Publications Warehouse

Karle, K.F.; Densmore, R.V.; ,

2001-01-01

Techniques for the hydraulic restoration of placer-mined streams and floodplains were developed in Denali National Park and Preserve, Alaska. The two-year study at Glen Creek focused on a design of stream and floodplain geometry using hydraulic capacity and shear stress equations. Slope and sinuosity values were based on regional relationships. Design requirements included a channel capacity for a bankfull discharge and a floodplain capacity for a 1.5- to 100-year discharge. Several bio-engineering techniques using alder and willow, including anchored brush bars, streambank hedge layering, seedlings, and cuttings, were tested to dissipate floodwater energy and encourage sediment deposition until natural revegetation stabilized the new floodplains. Permanently monumented cross-sections installed throughout the project site were surveyed every one to three years. Nine years after the project began, a summer flood caused substantial damage to the channel form, including a change in width/depth ratio, slope, and thalweg location. Many of the alder brush bars were heavily damaged or destroyed, resulting in significant bank erosion. This paper reviews the original hydraulic design process, and describes changes to the channel and floodplain geometry over time, based on nine years of cross-section surveys.

CORRELATES OF RECOVERY FROM ALCOHOL DEPENDENCE: A PROSPECTIVE STUDY OVER A 3-YEAR FOLLOW-UP INTERVAL

PubMed Central

Dawson, Deborah A.; Goldstein, Risë B.; Ruan, W. June; Grant, Bridget F.

2011-01-01

Background Correlates of recovery from alcohol dependence have been identified through a variety of study designs characterized by different strengths and limitations. The goal of this study was to compare correlates of recovery based on a 3-year prospective design with those based on cross-sectional analyses of data from the same source. Methods Data from the 2001-2002 Wave 1 and 2004-2005 Wave 2 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) were used to examine baseline characteristics associated with Wave 2 recovery from alcohol dependence, among those who classified with past-year DSM-IV alcohol dependence at Wave 1 (n=1,172). Results Abstinent recovery (AR) was significantly associated with Black/Asian/Hispanic race/ethnicity, children <1 year of age in the household at baseline, attending religious services ≥weekly at follow-up, and having initiated help seeking that comprised/included 12-step participation within <3 years prior to baseline. Nonabstinent recovery (NR) was positively associated with being never married at baseline, having job problems or being unemployed in the year preceding baseline, attending religious services

Spallation reaction study for the long-lived fission product 107Pd

NASA Astrophysics Data System (ADS)

Wang, He; Otsu, Hideaki; Sakurai, Hiroyoshi; Ahn, DeukSoon; Aikawa, Masayuki; Ando, Takashi; Araki, Shouhei; Chen, Sidong; Nobuyuki, Chiga; Doornenbal, Pieter; Fukuda, Naoki; Isobe, Tadaaki; Kawakami, Shunsuke; Kawase, Shoichiro; Kin, Tadahiro; Kondo, Yosuke; Koyama, Shunpei; Kubono, Shigeru; Maeda, Yukie; Makinaga, Ayano; Matsushita, Masafumi; Matsuzaki, Teiichiro; Michimasa, Shin'ichiro; Momiyama, Satoru; Nagamine, Shunsuke; Nakamura, Takashi; Nakano, Keita; Niikura, Megumi; Ozaki, Tomoyuki; Saito, Atsumi; Saito, Takeshi; Shiga, Yoshiaki; Shikata, Mizuki; Shimizu, Yohei; Shimoura, Susumu; Sumikama, Toshiyuki; Söderström, Pär-Anders; Suzuki, Hiroshi; Takeda, Hiroyuki; Takeuchi, Satoshi; Taniuchi, Ryo; Togano, Yasuhiro; Tsubota, Junichi; Uesaka, Meiko; Watanabe, Yasushi; Watanabe, Yukinobu; Wimmer, Kathrin; Yamamoto, Tatsuya; Yoshida, Koichi

2017-02-01

Spallation reactions for the long-lived fission product 107Pd have been studied for the purpose of nuclear waste transmutation. The cross sections on the proton- and deuteron-induced spallation were obtained at 196 and 118 MeV/nucleon in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Both the target and energy dependences of cross sections have been investigated systematically. It was found that the proton-induced cross sections at 196 MeV/nucleon are close to those for deuteron obtained at 118 MeV/nucleon for the light-mass products. The experimental data are compared with the SPACS semi-empirical parameterization and the PHITS calculations including both the intranuclear cascade and evaporation processes. Our data give a design goal of proton/deuteron flux for the transmutation of 107Pd using the spallation reaction. In addition, it is found that the spallation reaction at 118 MeV/nucleon may have an advantage over the 107Pd transmutation because of the low production of other long-lived radioactive isotopes.

Using environmental engineering to increase hand hygiene compliance: a cross-over study protocol

PubMed Central

Schmidtke, Kelly Ann; Aujla, Navneet; Marshall, Tom; Hussain, Abid; Hodgkinson, Gerard P; Arheart, Kristopher; Marti, Joachim; Birnbach, David J; Vlaev, Ivo

2017-01-01

Introduction Compliance with hand hygiene recommendations in hospital is typically less than 50%. Such low compliance inevitably contributes to hospital-acquired infections that negatively affect patients’ well-being and hospitals’ finances. The design of the present study is predicated on the assumption that most people who fail to clean their hands are not doing so intentionally, they just forget. The present study will test whether psychological priming can be used to increase the number of people who clean their hands on entering a ward. Here, we present the protocol for this study. Methods and analysis The study will use a randomised cross-over design. During the study, each of four wards will be observed during four conditions: olfactory prime, visual prime, both primes and neither prime. Each condition will be experienced for 42 days followed by a 7-day washout period (total duration of trial=189 days). We will record the number of people who enter each ward and whether they clean their hands during observation sessions, the amount of cleaning material used from the dispensers each week and the number of hospital-acquired infections that occur in each period. The outcomes will be compared using a regression analysis. Following the initial trail, the most effective priming condition will be rolled out for 3 months in all the wards. Ethics and dissemination Research ethics approval was obtained from the South Central—Oxford C Research Ethics Committee (16/SC/0554), the Health Regulatory Authority and the sponsor. Trial registration number ISRCTN (15397624); Edge ID 86357. PMID:28893752

QTL detection for forage quality and stem histology in four connected mapping populations of the model legume Medicago truncatula.

PubMed

Lagunes Espinoza, Luz Del Carmen; Julier, Bernadette

2013-02-01

Forage quality combines traits related to protein content and energy value. High-quality forages contribute to increase farm autonomy by reducing the use of energy or protein-rich supplements. Genetic analyses in forage legume species are complex because of their tetraploidy and allogamy. Indeed, no genetic studies of quality have been published at the molecular level on these species. Nonetheless, mapping populations of the model species M. truncatula can be used to detect QTL for forage quality. Here, we studied a crossing design involving four connected populations of M. truncatula. Each population was composed of ca. 200 recombinant inbred lines (RIL). We sought population-specific QTL and QTL explaining the whole design variation. We grew parents and RIL in a greenhouse for 2 or 3 seasons and analysed plants for chemical composition of vegetative organs (protein content, digestibility, leaf-to-stem ratio) and stem histology (stem cross-section area, tissue proportions). Over the four populations and all the traits, QTL were found on all chromosomes. Among these QTL, only four genomic regions, on chromosomes 1, 3, 7 and 8, contributed to explaining the variations in the whole crossing design. Surprisingly, we found that quality QTL were located in the same genomic regions as morphological QTL. We thus confirmed the quantitative inheritance of quality traits and tight relationships between quality and morphology. Our findings could be explained by a co-location of genes involved in quality and morphology. This study will help to detect candidate genes involved in quantitative variation for quality in forage legume species.

Cross-Layer Design for Space-Time coded MIMO Systems over Rice Fading Channel

NASA Astrophysics Data System (ADS)

Yu, Xiangbin; Zhou, Tingting; Liu, Xiaoshuai; Yin, Xin

A cross-layer design (CLD) scheme for space-time coded MIMO systems over Rice fading channel is presented by combining adaptive modulation and automatic repeat request, and the corresponding system performance is investigated well. The fading gain switching thresholds subject to a target packet error rate (PER) and fixed power constraint are derived. According to these results, and using the generalized Marcum Q-function, the calculation formulae of the average spectrum efficiency (SE) and PER of the system with CLD are derived. As a result, closed-form expressions for average SE and PER are obtained. These expressions include some existing expressions in Rayleigh channel as special cases. With these expressions, the system performance in Rice fading channel is evaluated effectively. Numerical results verify the validity of the theoretical analysis. The results show that the system performance in Rice channel is effectively improved as Rice factor increases, and outperforms that in Rayleigh channel.

Influence of strut cross-section of stents on local hemodynamics in stented arteries

NASA Astrophysics Data System (ADS)

Jiang, Yongfei; Zhang, Jun; Zhao, Wanhua

2016-05-01

Stenting is a very effective treatment for stenotic vascular diseases, but vascular geometries altered by stent implantation may lead to flow disturbances which play an important role in the initiation and progression of restenosis, especially in the near wall in stented arterial regions. So stent designs have become one of the indispensable factors needed to be considered for reducing the flow disturbances. In this paper, the structural designs of strut cross-section are considered as an aspect of stent designs to be studied in details. Six virtual stents with different strut cross-section are designed for deployments in the same ideal arterial model. Computational fluid dynamics (CFD) methods are performed to study how the shape and the aspect ratio (AR) of strut cross-section modified the local hemodynamics in the stented segments. The results indicate that stents with different strut cross-sections have different influence on the hemodynamics. Stents with streamlined cross-sectional struts for circular arc or elliptical arc can significantly enhance wall shear stress (WSS) in the stented segments, and reduce the flow disturbances around stent struts. The performances of stents with streamlined cross-sectional struts are better than that of stents with non-streamlined cross-sectional struts for rectangle. The results also show that stents with a larger AR cross-section are more conductive to improve the blood flow. The present study provides an understanding of the flow physics in the vicinity of stent struts and indicates that the shape and AR of strut cross-section ought to be considered as important factors to minimize flow disturbance in stent designs.

HFIR Fuel Casting Support

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

Imhoff, Seth D.; Gibbs, Paul Jacob; Solis, Eunice Martinez

Process exploration for fuel production for the High Flux Isotope Reactor (HFIR) using cast LEU-10wt.%Mo as an initial processing step has just begun. This project represents the first trials concerned with casting design and quality. The studies carried out over the course of this year and information contained in this report address the initial mold development to be used as a starting point for future operations. In broad terms, the final billet design is that of a solid rolling blank with an irregular octagonal cross section. The work covered here is a comprehensive view of the initial attempts to producemore » a sound casting. This report covers the efforts to simulate, predict, cast, inspect, and revise the initial mold design.« less

Polydextrose: its impact on short-term food intake and subjective feelings of satiety in males-a randomized controlled cross-over study.

PubMed

Ranawana, Viren; Muller, Adelaide; Henry, C Jeya K

2013-04-01

Polydextrose is a low-calorie highly branched-chain glucose polymer that is poorly digested in the upper gastrointestinal tract and therefore demonstrates fibre-like properties. Fibre has been shown to increase satiety and possibly reduce food intake. Therefore, the objective of the current study was to examine the effects of polydextrose on short-term satiety and energy intake. In a repeated-measures randomized blind cross-over design, 26 healthy males consumed a 400-g fruit smoothie containing 12 g (3 %) of polydextrose, and a buffet lunch 60 min after the smoothie. Motivational ratings for satiety and palatability and lunch energy intake were measured. The effects of the polydextrose-containing smoothie were compared against a polydextrose-free control smoothie. Polydextrose did not significantly alter the taste and palatability of the fruit smoothie. Consuming the polydextrose-containing smoothie resulted in a significantly lower energy intake at lunch (102 kcal less) compared to the control. Polydextrose may be a good fortificant for reducing short-term food intake.

Influence of Caffeine Ingestion on Perceived Mood States, Concentration, and Arousal Levels during a 75-Min University Lecture

ERIC Educational Resources Information Center

Peeling, Peter; Dawson, Brian

2007-01-01

This investigation aimed to assess the effect of a caffeine supplement on perceived mood state, concentration, and arousal during a 75-min university lecture. Methods. This randomized, blind, cross-over design investigation ran over a course of 2 consecutive weeks. During "week" 1, 10 third-year Human Movement and Exercise Science…

A Design-Based Research Case Study Documenting a Constructivist ID Process and Instructional Solution for a Cross-Cultural Workforce

ERIC Educational Resources Information Center

Tracey, Monica W.; Unger, Kelly L.

2012-01-01

As the need for instructing a globalized workforce increases, instructional designers must embrace the constraints and the opportunities these projects provide in order to move the field of cross-cultural instructional design (ID) forward. Cross-cultural projects offer multiple avenues for growth in ID practice, overcoming cultural barriers, and a…

Measuring Knowledge Integration Learning of Energy Topics: A two-year longitudinal study

NASA Astrophysics Data System (ADS)

Liu, Ou Lydia; Ryoo, Kihyun; Linn, Marcia C.; Sato, Elissa; Svihla, Vanessa

2015-05-01

Although researchers call for inquiry learning in science, science assessments rarely capture the impact of inquiry instruction. This paper reports on the development and validation of assessments designed to measure middle-school students' progress in gaining integrated understanding of energy while studying an inquiry-oriented curriculum. The assessment development was guided by the knowledge integration framework. Over 2 years of implementation, more than 4,000 students from 4 schools participated in the study, including a cross-sectional and a longitudinal cohort. Results from item response modeling analyses revealed that: (a) the assessments demonstrated satisfactory psychometric properties in terms of reliability and validity; (b) both the cross-sectional and longitudinal cohorts made progress on integrating their understanding energy concepts; and (c) among many factors (e.g. gender, grade, school, and home language) associated with students' science performance, unit implementation was the strongest predictor.

How do children acquire early grammar and build multiword utterances? A corpus study of French children aged 2 to 4.

PubMed

Le Normand, M T; Moreno-Torres, I; Parisse, C; Dellatolas, G

2013-01-01

In the last 50 years, researchers have debated over the lexical or grammatical nature of children's early multiword utterances. Due to methodological limitations, the issue remains controversial. This corpus study explores the effect of grammatical, lexical, and pragmatic categories on mean length of utterances (MLU). A total of 312 speech samples from high-low socioeconomic status (SES) French-speaking children aged 2-4 years were annotated with a part-of-speech-tagger. Multiple regression analyses show that grammatical categories, particularly the most frequent subcategories, were the best predictors of MLU both across age and SES groups. These findings support the view that early language learning is guided by grammatical rather than by lexical words. This corpus research design can be used for future cross-linguistic and cross-pathology studies. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

Description of research design of articles published in four Brazilian physical therapy journals

PubMed Central

Saragiotto, Bruno T.; Costa, Lucíola C. M.; Oliveira, Ronaldo F.; Lopes, Alexandre D.; Moseley, Anne M.; Costa, Leonardo O. P.

2014-01-01

Background While the research design of articles published in medical journals and in some physical therapy journals has already been evaluated, this has not been investigated in Brazilian physical therapy journals. Objective To describe the research design used in all articles published in Brazilian scientific journals that are freely available, have high Qualis rankings, and are relevant to physical therapy over a 7-year period. Method We extracted the bibliometric data, research design, research type (human or animal), and clinical area for all articles published. The articles were grouped into their level of evidence, and descriptive analyses were performed. We calculated the frequency, proportions of articles, and 95% confidence interval of these proportions with each research design in each journal. We cross-tabulated the clinical areas with research designs (expressed as number and percentages). Results A total of 1,458 articles from four Brazilian journals were found: Revista Brasileira de Fisioterapia, Revista Fisioterapia em Movimento, Revista Fisioterapia e Pesquisa, and Revista Acta Fisiátrica. The majority of articles were classified as level II of evidence (60%), followed by level III (29%) and level I (10%). The most prevalent research designs were cross-sectional studies (38%), single-case or case-series studies, and narrative reviews. Most articles reported human research and were in the musculoskeletal, neurologic, and cardiothoracic areas. Conclusions Most of the research published in Brazilian physical therapy journals used levels II and III of evidence. Increasing the publication rate of systematic reviews and randomized controlled trials would provide more high-quality evidence to guide evidence-based physical therapy practice. PMID:24675913

Description of research design of articles published in four Brazilian physical therapy journals.

PubMed

Saragiotto, Bruno T; Costa, Lucíola C M; Oliveira, Ronaldo F; Lopes, Alexandre D; Moseley, Anne M; Costa, Leonardo O P

2014-01-01

While the research design of articles published in medical journals and in some physical therapy journals has already been evaluated, this has not been investigated in Brazilian physical therapy journals. Objective : To describe the research design used in all articles published in Brazilian scientific journals that are freely available, have high Qualis rankings, and are relevant to physical therapy over a 7-year period. We extracted the bibliometric data, research design, research type (human or animal), and clinical area for all articles published. The articles were grouped into their level of evidence, and descriptive analyses were performed. We calculated the frequency, proportions of articles, and 95% confidence interval of these proportions with each research design in each journal. We cross-tabulated the clinical areas with research designs (expressed as number and percentages). A total of 1,458 articles from four Brazilian journals were found: Revista Brasileira de Fisioterapia, Revista Fisioterapia em Movimento, Revista Fisioterapia e Pesquisa, and Revista Acta Fisiátrica. The majority of articles were classified as level II of evidence (60%), followed by level III (29%) and level I (10%). The most prevalent research designs were cross-sectional studies (38%), single-case or case-series studies, and narrative reviews. Most articles reported human research and were in the musculoskeletal, neurologic, and cardiothoracic areas. Most of the research published in Brazilian physical therapy journals used levels II and III of evidence. Increasing the publication rate of systematic reviews and randomized controlled trials would provide more high-quality evidence to guide evidence-based physical therapy practice.

The Communicability of Graphical Alternatives to Tabular Displays of Statistical Simulation Studies

PubMed Central

Cook, Alex R.; Teo, Shanice W. L.

2011-01-01

Simulation studies are often used to assess the frequency properties and optimality of statistical methods. They are typically reported in tables, which may contain hundreds of figures to be contrasted over multiple dimensions. To assess the degree to which these tables are fit for purpose, we performed a randomised cross-over experiment in which statisticians were asked to extract information from (i) such a table sourced from the literature and (ii) a graphical adaptation designed by the authors, and were timed and assessed for accuracy. We developed hierarchical models accounting for differences between individuals of different experience levels (under- and post-graduate), within experience levels, and between different table-graph pairs. In our experiment, information could be extracted quicker and, for less experienced participants, more accurately from graphical presentations than tabular displays. We also performed a literature review to assess the prevalence of hard-to-interpret design features in tables of simulation studies in three popular statistics journals, finding that many are presented innumerately. We recommend simulation studies be presented in graphical form. PMID:22132184

The communicability of graphical alternatives to tabular displays of statistical simulation studies.

PubMed

Cook, Alex R; Teo, Shanice W L

2011-01-01

Simulation studies are often used to assess the frequency properties and optimality of statistical methods. They are typically reported in tables, which may contain hundreds of figures to be contrasted over multiple dimensions. To assess the degree to which these tables are fit for purpose, we performed a randomised cross-over experiment in which statisticians were asked to extract information from (i) such a table sourced from the literature and (ii) a graphical adaptation designed by the authors, and were timed and assessed for accuracy. We developed hierarchical models accounting for differences between individuals of different experience levels (under- and post-graduate), within experience levels, and between different table-graph pairs. In our experiment, information could be extracted quicker and, for less experienced participants, more accurately from graphical presentations than tabular displays. We also performed a literature review to assess the prevalence of hard-to-interpret design features in tables of simulation studies in three popular statistics journals, finding that many are presented innumerately. We recommend simulation studies be presented in graphical form.

Correction of sampling bias in a cross-sectional study of post-surgical complications.

PubMed

Fluss, Ronen; Mandel, Micha; Freedman, Laurence S; Weiss, Inbal Salz; Zohar, Anat Ekka; Haklai, Ziona; Gordon, Ethel-Sherry; Simchen, Elisheva

2013-06-30

Cross-sectional designs are often used to monitor the proportion of infections and other post-surgical complications acquired in hospitals. However, conventional methods for estimating incidence proportions when applied to cross-sectional data may provide estimators that are highly biased, as cross-sectional designs tend to include a high proportion of patients with prolonged hospitalization. One common solution is to use sampling weights in the analysis, which adjust for the sampling bias inherent in a cross-sectional design. The current paper describes in detail a method to build weights for a national survey of post-surgical complications conducted in Israel. We use the weights to estimate the probability of surgical site infections following colon resection, and validate the results of the weighted analysis by comparing them with those obtained from a parallel study with a historically prospective design. Copyright © 2012 John Wiley & Sons, Ltd.

Comparison between self-formulation and compounded-formulation dexamethasone mouth rinse for oral lichen planus: a pilot, randomized, cross-over trial.

PubMed

Hambly, Jessica L; Haywood, Alison; Hattingh, Laetitia; Nair, Raj G

2017-08-01

There is a lack of appropriate, commercially-available topical corticosteroid formulations for use in oral lichen planus (OLP) and oral lichenoid reaction. Current therapy includes crushing a dexamethasone tablet and mixing it with water for use as a mouth rinse. This formulation is unpleasant esthetically and to use in the mouth, as it is a bitter and gritty suspension, resulting in poor compliance. Thus, the present study was designed to formulate and pilot an effective, esthetically-pleasing formulation. A single-blinded, cross-over trial was designed with two treatment arms. Patients were monitored for 7 weeks. Quantitative and qualitative data was assessed using VAS, numeric pain scales, the Treatment Satisfaction Questionnaire for Medication-9, and thematic analysis to determine primary patient-reported outcomes, including satisfaction, compliance, quality of life, and symptom relief. Nine patients completed the pilot trial. Data analysis revealed the new compounded formulation to be superior to existing therapy due to its convenience, positive contribution to compliance, patient-perceived faster onset of action, and improved symptom relief. Topical dexamethasone is useful in the treatment of OLP. When carefully formulated into a compounded mouth rinse, it improves patient outcomes. © 2016 John Wiley & Sons Australia, Ltd.

Ultrathin Six-Band Polarization-Insensitive Perfect Metamaterial Absorber Based on a Cross-Cave Patch Resonator for Terahertz Waves

PubMed Central

Cheng, Yong Zhi; Huang, Mu Lin; Chen, Hao Ran; Guo, Zhen Zhong; Mao, Xue Song; Gong, Rong Zhou

2017-01-01

A simple design of an ultrathin six-band polarization-insensitive terahertz perfect metamaterial absorber (PMMA), composed of a metal cross-cave patch resonator (CCPR) placed over a ground plane, was proposed and investigated numerically. The numerical simulation results demonstrate that the average absorption peaks are up to 95% at six resonance frequencies. Owing to the ultra-narrow band resonance absorption of the structure, the designed PMMA also exhibits a higher Q factor (>65). In addition, the absorption properties can be kept stable for both normal incident transverse magnetic (TM) and transverse electric (TE) waves. The physical mechanism behind the observed high-level absorption is illustrated by the electric and power loss density distributions. The perfect absorption originates mainly from the higher-order multipolar plasmon resonance of the structure, which differs sharply from most previous studies of PMMAs. Furthermore, the resonance absorption properties of the PMMA can be modified and adjusted easily by varying the geometric parameters of the unit cell. PMID:28772951

Testing of the permanent magnet material Mn-Al-C for potential use in propulsion motors for electric vehicles

NASA Technical Reports Server (NTRS)

Abdelnour, Z.; Mildrun, H.; Strant, K.

1981-01-01

The development of Mn-Al-C permanent magnets is reviewed. The general properties of the material are discussed and put into perspective relative to alnicos and ferrites. The traction motor designer's demands of a permanent magnet for potential use in electric vehicle drives are reviewed. Tests determined magnetic design data and mechanical strength properties. Easy axis hysteresis and demagnetization curves, recoil loops and other minor loop fields were measured over a temperature range from -50 to 150 C. Hysteresis loops were also measured for three orthogonal directions (the one easy and two hard axes of magnetization). Extruded rods of three different diameters were tested. The nonuniformity of properties over the cross section of the 31 mm diameter rod was studied. Mechanical compressive and bending strength at room temperature was determined on individual samples from the 31 mm rod.

Relative bioavailability of methadone hydrochloride administered in chewing gum and tablets.

PubMed

Christrup, L L; Angelo, H R; Bonde, J; Kristensen, F; Rasmussen, S N

1990-01-01

Methadone administered in chewing gum in doses of 16.7-22.6 mg to seven patients in a study using an open balanced cross-over design, was compared with 20 mg of methadone given perorally as tablets. There was no significant difference in the AUC/D obtained after administration of chewing gum and tablets (p greater than 0.05). It is concluded that the chewing gum formulation should be considered for further testing with respect to suppression of abstinence syndrome in narcotic addicts.

Magnetohydrodynamic Augmented Propulsion Experiment

NASA Technical Reports Server (NTRS)

Litchford, Ron J.

2008-01-01

Over the past several years, efforts have been under way to design and develop an operationally flexible research facility for investigating the use of cross-field MHD accelerators as a potential thrust augmentation device for thermal propulsion systems. The baseline configuration for this high-power experimental facility utilizes a 1.5-MWe multi-gas arc-heater as a thermal driver for a 2-MWe MHD accelerator, which resides in a large-bore 2-tesla electromagnet. A preliminary design study using NaK seeded nitrogen as the working fluid led to an externally diagonalized segmented MHD channel configuration based on an expendable heat-sink design concept. The current status report includes a review of engineering/design work and performance optimization analyses and summarizes component hardware fabrication and development efforts, preliminary testing results, and recent progress toward full-up assembly and testing

Status of Magnetohydrodynamic Augmented Propulsion Experiment

NASA Technical Reports Server (NTRS)

Litchford, Ron J.; Lineberry, John T.

2007-01-01

Over the past several years, efforts have been under way to design and develop an operationally flexible research facility for investigating the use of cross-field MHD accelerators as a potential thrust augmentation device for thermal propulsion systems, The baseline configuration for this high-power experimental facility utilizes a 1,5-MW, multi-gas arc-heater as a thermal driver for a 2-MW, MHD accelerator, which resides in a large-bore 2-tesla electromagnet. A preliminary design study using NaK seeded nitrogen as the working fluid led to an externally diagonalized segmented MHD channel configuration based on an expendable beat-sink design concept. The current status report includes a review of engineering/design work and performance optimization analyses and summarizes component hardware fabrication and development efforts, preliminary testing results, and recent progress toward full-up assembly and testing

The Neighbourhood Effects on Health and Well-being (NEHW) study.

PubMed

O'Campo, Patricia; Wheaton, Blair; Nisenbaum, Rosane; Glazier, Richard H; Dunn, James R; Chambers, Catharine

2015-01-01

Many cross-sectional studies of neighbourhood effects on health do not employ strong study design elements. The Neighbourhood Effects on Health and Well-being (NEHW) study, a random sample of 2412 English-speaking Toronto residents (age 25-64), utilises strong design features for sampling neighbourhoods and individuals, characterising neighbourhoods using a variety of data sources, measuring a wide range of health outcomes, and for analysing cross-level interactions. We describe here methodological issues that shaped the design and analysis features of the NEHW study to ensure that, while a cross-sectional sample, it will advance the quality of evidence emerging from observational studies. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Comparative evaluation of stress levels before, during, and after periodontal surgical procedures with and without nitrous oxide-oxygen inhalation sedation

PubMed Central

Sandhu, Gurkirat; Khinda, Paramjit Kaur; Gill, Amarjit Singh; Singh Khinda, Vineet Inder; Baghi, Kamal; Chahal, Gurparkash Singh

2017-01-01

Context: Periodontal surgical procedures produce varying degree of stress in all patients. Nitrous oxide-oxygen inhalation sedation is very effective for adult patients with mild-to-moderate anxiety due to dental procedures and needle phobia. Aim: The present study was designed to perform periodontal surgical procedures under nitrous oxide-oxygen inhalation sedation and assess whether this technique actually reduces stress physiologically, in comparison to local anesthesia alone (LA) during lengthy periodontal surgical procedures. Settings and Design: This was a randomized, split-mouth, cross-over study. Materials and Methods: A total of 16 patients were selected for this randomized, split-mouth, cross-over study. One surgical session (SS) was performed under local anesthesia aided by nitrous oxide-oxygen inhalation sedation, and the other SS was performed on the contralateral quadrant under LA. For each session, blood samples to measure and evaluate serum cortisol levels were obtained, and vital parameters including blood pressure, heart rate, respiratory rate, and arterial blood oxygen saturation were monitored before, during, and after periodontal surgical procedures. Statistical Analysis Used: Paired t-test and repeated measure ANOVA. Results: The findings of the present study revealed a statistically significant decrease in serum cortisol levels, blood pressure and pulse rate and a statistically significant increase in respiratory rate and arterial blood oxygen saturation during periodontal surgical procedures under nitrous oxide inhalation sedation. Conclusion: Nitrous oxide-oxygen inhalation sedation for periodontal surgical procedures is capable of reducing stress physiologically, in comparison to LA during lengthy periodontal surgical procedures. PMID:29386796

The effects of physical therapy with neuromuscular electrical stimulation in patients with septic shock: Study protocol for a randomized cross-over design.

PubMed

Lago, Alessandra Fabiane; de Oliveira, Anamaria Siriani; de Souza, Hugo Celso Dutra; da Silva, João Santana; Basile-Filho, Anibal; Gastaldi, Ada Clarice

2018-02-01

Septic shock is a potentially fatal organ dysfunction caused by an imbalance of the host response to infection. The changes in microcirculation during sepsis can be explained by the alterations in the endothelial barrier function. Endothelial progenitor cells (EPCs) are a potential recovery index of endothelial function and it an increase in response to neuromuscular electrical stimulation (NMES) was demonstrated. Therefore, the objective of this study is to investigate the effects of NMES in patients with septic shock. It is a study protocol for a randomized cross-over design in an intensive care unit of a tertiary University hospital. Thirty-one patients aged 18 to 65 years. The study will be divided in 2 phases: the phase one will be held in the first 72 hours of septic shock and the phase two after 3 days of first assessment. Patients will be randomly selected to the intervention protocol (decubitus position with the limbs raised and NMES) and control protocol (decubitus position with the limbs raised without NMES). After this procedure, the patients will be allocated in group 1 (intervention and control protocol) or group 2 (control and intervention protocol) with a wash-out period of 4 to 6 hours between them. The main outcome is mobilization of EPCs. The secondary outcome is metabolic and hemodynamic data. A linear mixed model will be used for analysis of dependent variables and estimated values of the mean of the differences of each effect.

Cross-Validation of Survival Bump Hunting by Recursive Peeling Methods.

PubMed

Dazard, Jean-Eudes; Choe, Michael; LeBlanc, Michael; Rao, J Sunil

2014-08-01

We introduce a survival/risk bump hunting framework to build a bump hunting model with a possibly censored time-to-event type of response and to validate model estimates. First, we describe the use of adequate survival peeling criteria to build a survival/risk bump hunting model based on recursive peeling methods. Our method called "Patient Recursive Survival Peeling" is a rule-induction method that makes use of specific peeling criteria such as hazard ratio or log-rank statistics. Second, to validate our model estimates and improve survival prediction accuracy, we describe a resampling-based validation technique specifically designed for the joint task of decision rule making by recursive peeling (i.e. decision-box) and survival estimation. This alternative technique, called "combined" cross-validation is done by combining test samples over the cross-validation loops, a design allowing for bump hunting by recursive peeling in a survival setting. We provide empirical results showing the importance of cross-validation and replication.

Cross-Validation of Survival Bump Hunting by Recursive Peeling Methods

PubMed Central

Dazard, Jean-Eudes; Choe, Michael; LeBlanc, Michael; Rao, J. Sunil

2015-01-01

We introduce a survival/risk bump hunting framework to build a bump hunting model with a possibly censored time-to-event type of response and to validate model estimates. First, we describe the use of adequate survival peeling criteria to build a survival/risk bump hunting model based on recursive peeling methods. Our method called “Patient Recursive Survival Peeling” is a rule-induction method that makes use of specific peeling criteria such as hazard ratio or log-rank statistics. Second, to validate our model estimates and improve survival prediction accuracy, we describe a resampling-based validation technique specifically designed for the joint task of decision rule making by recursive peeling (i.e. decision-box) and survival estimation. This alternative technique, called “combined” cross-validation is done by combining test samples over the cross-validation loops, a design allowing for bump hunting by recursive peeling in a survival setting. We provide empirical results showing the importance of cross-validation and replication. PMID:26997922

Rationale and design of a long term follow-up study of women who did and did not receive HPV 16/18 vaccination in Guanacaste, Costa Rica.

PubMed

Gonzalez, Paula; Hildesheim, Allan; Herrero, Rolando; Katki, Hormuzd; Wacholder, Sholom; Porras, Carolina; Safaeian, Mahboobeh; Jimenez, Silvia; Darragh, Teresa M; Cortes, Bernal; Befano, Brian; Schiffman, Mark; Carvajal, Loreto; Palefsky, Joel; Schiller, John; Ocampo, Rebeca; Schussler, John; Lowy, Douglas; Guillen, Diego; Stoler, Mark H; Quint, Wim; Morales, Jorge; Avila, Carlos; Rodriguez, Ana Cecilia; Kreimer, Aimée R

2015-04-27

The Costa Rica Vaccine Trial (CVT) was a randomized clinical trial conducted between 2004 and 2010, which randomized 7466 women aged 18 to 25 to receive the bivalent HPV-16/18 vaccine or control Hepatitis-A vaccine. Participants were followed for 4 years with cross-over vaccination at the study end. In 2010 the long term follow-up (LTFU) study was initiated to evaluate the 10-year impact of HPV-16/18 vaccination, determinants of the immune response, and HPV natural history in a vaccinated population. Herein, the rationale, design and methods of the LTFU study are described, which actively follows CVT participants in the HPV-arm 6 additional years at biennial intervals (3 additional study visits for 10 years of total follow-up), or more often if clinically indicated. According to the initial commitment, women in the Hepatitis-A arm were offered HPV vaccination at cross-over; they were followed 2 additional years and exited from the study. 92% of eligible CVT women accepted participation in LTFU. To provide underlying rates of HPV acquisition and cervical disease among unvaccinated women to compare with the HPV-arm during LTFU, a new unvaccinated control group (UCG) of women who are beyond the age generally recommended for routine vaccination was enrolled, and will be followed by cervical cancer screening over 6 years. To form the UCG, 5000 women were selected from a local census, of whom 2836 women (61% of eligible women) agreed to participate. Over 90% of participants complied with an interview, blood and cervical specimen collection. Evaluation of comparability between the original (Hepatitis-A arm of CVT) and new (UCG) control groups showed that women's characteristics, as well as their predicted future risk for cervical HPV acquisition, were similar, thus validating use of the UCG. LTFU is poised to comprehensively address many important questions related to long-term effects of prophylactic HPV vaccines. Copyright © 2015 Elsevier Ltd. All rights reserved.

An Assessment of the Crossed Porro Prism Resonator

DTIC Science & Technology

1980-08-01

to P n 7 + 4tan-{(4( 1 - 2/(n) 2) In the laser, the plane polarised beam from the polarising beam splitter ERL-OI(2-TM - 2 - will, on emerging from... Beam intensities in resonators 17. Ray path rotation in crossed porro resonator 18. Elliptically polarised light ray - I I•HI,-O ,-0162-IM I...military laser rangefinder and designator applications. This paper reviews the properties of these devices and examines the advantages over normal mirror

Using cheminformatics to predict cross reactivity of “designer drugs” to their currently available immunoassays

PubMed Central

2014-01-01

Background A challenge for drug of abuse testing is presented by ‘designer drugs’, compounds typically discovered by modifications of existing clinical drug classes such as amphetamines and cannabinoids. Drug of abuse screening immunoassays directed at amphetamine or methamphetamine only detect a small subset of designer amphetamine-like drugs, and those immunoassays designed for tetrahydrocannabinol metabolites generally do not cross-react with synthetic cannabinoids lacking the classic cannabinoid chemical backbone. This suggests complexity in understanding how to detect and identify whether a patient has taken a molecule of one class or another, impacting clinical care. Methods Cross-reactivity data from immunoassays specifically targeting designer amphetamine-like and synthetic cannabinoid drugs was collected from multiple published sources, and virtual chemical libraries for molecular similarity analysis were built. The virtual library for synthetic cannabinoid analysis contained a total of 169 structures, while the virtual library for amphetamine-type stimulants contained 288 compounds. Two-dimensional (2D) similarity for each test compound was compared to the target molecule of the immunoassay undergoing analysis. Results 2D similarity differentiated between cross-reactive and non-cross-reactive compounds for immunoassays targeting mephedrone/methcathinone, 3,4-methylenedioxypyrovalerone, benzylpiperazine, mephentermine, and synthetic cannabinoids. Conclusions In this study, we applied 2D molecular similarity analysis to the designer amphetamine-type stimulants and synthetic cannabinoids. Similarity calculations can be used to more efficiently decide which drugs and metabolites should be tested in cross-reactivity studies, as well as to design experiments and potentially predict antigens that would lead to immunoassays with cross reactivity for a broader array of designer drugs. PMID:24851137

Design, synthesis and biological evaluation of a bivalent micro opiate and adenosine A1 receptor antagonist.

PubMed

Mathew, Smitha C; Ghosh, Nandita; By, Youlet; Berthault, Aurélie; Virolleaud, Marie-Alice; Carrega, Louis; Chouraqui, Gaëlle; Commeiras, Laurent; Condo, Jocelyne; Attolini, Mireille; Gaudel-Siri, Anouk; Ruf, Jean; Parrain, Jean-Luc; Rodriguez, Jean; Guieu, Régis

2009-12-01

The cross talk between different membrane receptors is the source of increasing research. We designed and synthesized a new hetero-bivalent ligand that has antagonist properties on both A(1) adenosine and mu opiate receptors with a K(i) of 0.8+/-0.05 and 0.7+/-0.03 microM, respectively. This hybrid molecule increases cAMP production in cells that over express the mu receptor as well as those over expressing the A(1) adenosine receptor and reverses the antalgic effects of mu and A(1) adenosine receptor agonists in animals.

Advantages of using voiced questionnaire and image capture application for data collection from a minority group in rural areas along the Thailand-Myanmar border.

PubMed

Monyarit, Siriporn; Pan-ngum, Wirichada; Lawpoolsri, Saranath; Yimsamran, Surapon; Pongnumkul, Suporn; Kaewkungwal, Jaranit; Singhasivanon, Pratap

2014-01-01

To compare the quality of data collection via electronic data capture (EDC) with voiced questionnaire (QNN) and data image capture features using a tablet versus standard paper-based QNN, to assess the user's perception of using the EDC tool, and to compare user satisfaction with the two methods. Randomised cross-over study. Study sites: This study was conducted in two villages along the Thailand-Myanmar border. This study included 30 community health volunteers (CHVs) and 120 Karen hill tribe villagers. Employing a cross-over study design, the CHVs were allocated randomly to two groups, in which they performed interviews in different sequences using EDC and QNN. Data discrepancies were found between the two data-collection methods, when data from the paper-based and image-capture methods were compared, and when conducting skip pattern questions. More than 90% of the CHVs perceived the EDC to be useful and easy to use. Both interviewers and interviewees were more satisfied with the EDC compared with QNN in terms of format, ease of use, and system speed. The EDC can effectively be used as an alternative method to paper-based QNNs for data collection. It produces more accurate data that can be considered evidence-based.

Continuous vs. blocks of physiotherapy for motor development in children with cerebral palsy and similar syndromes: A prospective randomized study.

PubMed

Brunner, Anne-Louise; Rutz, Erich; Juenemann, Stephanie; Brunner, Reinald

2014-12-01

To determine whether physiotherapy is more effective when applied in blocks or continuously in children with cerebral palsy (CP). A prospective randomized cross-over design study compared the effect of regular physiotherapy (baseline) with blocks of physiotherapy alternating with no physiotherapy over one year. Thirty-nine institutionalized children with CP and clinically similar syndromes (6-16 years old, Gross Motor Function Classification Scale II-IV) were included. During the first scholastic year, group A received regular physiotherapy, group B blocks of physiotherapy and vice versa in the second year. The Gross Motor Function Measure 66 (GMFM-66) was the outcome measure. Thirteen children in each group completed the study. GMFM-66 improved (p < 0.05) over the study period in both groups in total; changes (p < 0.05) were seen only in dimension D (group B) and E (both groups) during regular therapy. Physiotherapy may be more effective when provided regularly rather than in blocks.

Cross-layer protocol design for QoS optimization in real-time wireless sensor networks

NASA Astrophysics Data System (ADS)

Hortos, William S.

2010-04-01

The metrics of quality of service (QoS) for each sensor type in a wireless sensor network can be associated with metrics for multimedia that describe the quality of fused information, e.g., throughput, delay, jitter, packet error rate, information correlation, etc. These QoS metrics are typically set at the highest, or application, layer of the protocol stack to ensure that performance requirements for each type of sensor data are satisfied. Application-layer metrics, in turn, depend on the support of the lower protocol layers: session, transport, network, data link (MAC), and physical. The dependencies of the QoS metrics on the performance of the higher layers of the Open System Interconnection (OSI) reference model of the WSN protocol, together with that of the lower three layers, are the basis for a comprehensive approach to QoS optimization for multiple sensor types in a general WSN model. The cross-layer design accounts for the distributed power consumption along energy-constrained routes and their constituent nodes. Following the author's previous work, the cross-layer interactions in the WSN protocol are represented by a set of concatenated protocol parameters and enabling resource levels. The "best" cross-layer designs to achieve optimal QoS are established by applying the general theory of martingale representations to the parameterized multivariate point processes (MVPPs) for discrete random events occurring in the WSN. Adaptive control of network behavior through the cross-layer design is realized through the parametric factorization of the stochastic conditional rates of the MVPPs. The cross-layer protocol parameters for optimal QoS are determined in terms of solutions to stochastic dynamic programming conditions derived from models of transient flows for heterogeneous sensor data and aggregate information over a finite time horizon. Markov state processes, embedded within the complex combinatorial history of WSN events, are more computationally tractable and lead to simplifications for any simulated or analytical performance evaluations of the cross-layer designs.

Low-cost warning device industry assessment : research results.

DOT National Transportation Integrated Search

2011-12-01

Virtually all of the grade crossing train detection and warning systems in the United States use a variant of the track circuit technology developed over a century ago. Track circuits have evolved through the years, but the design and principles of o...

Use of adjuvants for enhancement of rectal absorption of cefoxitin in humans.

PubMed Central

Davis, S S; Burnham, W R; Wilson, P; O'Brien, J

1985-01-01

The biological availability of cefoxitin administered rectally in the form of suppositories was examined in six human subjects by a cross-over design. Four different suppository systems containing adjuvants expected to enhance the absorption of the drug were studied. The presence of sodium salicylate and a nonionic surface-active agent, Brij 35, gave increased bioavailability as high as 20% compared with 3% for a system without adjuvants. The quantity of sodium salicylate was found to have an influence on the quantity of cefoxitin absorbed, and the salicylate was absorbed over an extended period of time from the rectum. The suppositories were well tolerated, and there were no adverse effects on bowel flora. PMID:3834830

Using environmental engineering to increase hand hygiene compliance: a cross-over study protocol.

PubMed

Schmidtke, Kelly Ann; Aujla, Navneet; Marshall, Tom; Hussain, Abid; Hodgkinson, Gerard P; Arheart, Kristopher; Marti, Joachim; Birnbach, David J; Vlaev, Ivo

2017-09-11

Compliance with hand hygiene recommendations in hospital is typically less than 50%. Such low compliance inevitably contributes to hospital-acquired infections that negatively affect patients' well-being and hospitals' finances. The design of the present study is predicated on the assumption that most people who fail to clean their hands are not doing so intentionally, they just forget. The present study will test whether psychological priming can be used to increase the number of people who clean their hands on entering a ward. Here, we present the protocol for this study. The study will use a randomised cross-over design. During the study, each of four wards will be observed during four conditions: olfactory prime, visual prime, both primes and neither prime. Each condition will be experienced for 42 days followed by a 7-day washout period (total duration of trial=189 days). We will record the number of people who enter each ward and whether they clean their hands during observation sessions, the amount of cleaning material used from the dispensers each week and the number of hospital-acquired infections that occur in each period. The outcomes will be compared using a regression analysis. Following the initial trail, the most effective priming condition will be rolled out for 3 months in all the wards. Research ethics approval was obtained from the South Central-Oxford C Research Ethics Committee (16/SC/0554), the Health Regulatory Authority and the sponsor. ISRCTN (15397624); Edge ID 86357. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Cardiorespiratory fitness and hip bone mineral density in women: a 6-year prospective study.

PubMed

Tucker, Larry A; Nokes, Neil R; Bailey, Bruce W; Lecheminant, James D

2014-10-01

Cross-sectional studies and short term interventions focusing on fitness and bone mineral density (BMD) are common. However, few investigations have studied the effect of fitness on BMD over an extended period of time. The present study was conducted to determine the extent to which cardiorespiratory fitness influences risk of BMD loss at the hip over 6 yr. A prospective cohort design was used with 245 healthy, middle-aged women. Hip BMD was assessed using dual energy x-ray absorptiometry. Calcium and vitamin D were measured using the Block Food Frequency Questionnaire. Menopause status was measured by a questionnaire. Results showed that fit and unfit women experienced similar changes in hip BMD over time. Specifically, unfit women experienced a non-significant 7% increased risk of losing hip BMD compared to their counterparts (RR = 1.07, 95% CI = 0.66, 1.73). Adjusting statistically for differences in age, initial body weight, and hip BMD, weight change, menopause status, calcium and vitamin D intake, and time between assessments had little effect on the relationship. Fitness level did not influence risk of hip BMD loss over time.

Stream channel responses and soil loss at off-highway vehicle stream crossings in the Ouachita National Forest

Treesearch

Daniel A. Marion; Jonathan D. Phillips; Chad Yocum; Stephanie H. Mehlhope

2014-01-01

This study investigates the geomorphic effects of ford-type stream crossings in an off-highway vehicle (OHV) trail complex in the Ouachita National Forest, Arkansas. At a total of 15 crossing sites, we used a disturbed vs. undisturbed study design to assess soil truncation and an upstream vs. downstream design to assess in-channel effects. The 15 sites ranged from OHV...

The Influence of Game Design on the Collaborative Problem Solving Process: A Cross-Case Study of Multi-Player Collaborative Gameplay Analysis

ERIC Educational Resources Information Center

Yildirim, Nilay

2013-01-01

This cross-case study examines the relationships between game design attributes and collaborative problem solving process in the context of multi-player video games. The following game design attributes: sensory stimuli elements, level of challenge, and presentation of game goals and rules were examined to determine their influence on game…

Changing epistemologies under conditions of social change in two Arab communities in Israel.

PubMed

Weinstock, Michael

2015-02-01

The study of epistemic thinking focuses on how people understand and coordinate objective and subjective aspects of knowing and make sense of multiple and discrepant knowledge claims. Typically described in terms of normative development, cross-cultural studies show differences in epistemic development and characteristics of epistemic thinking. This study focuses on within-culture variations of epistemic thinking, with the assumption that social change will produce changes in development. Arab society in Israel has undergone notable change over the last half century. In this cross-sectional research design, cross-generational comparison and rural-urban comparison were used as proxies for longitudinal social change. Three generations of Muslim Arab women in a village in Israel (20 adolescents, 20 mothers and 20 grandmothers) and 20 Muslim Arab adolescents from a large, mixed city in the same region responded to six dilemmas invoking epistemic thinking. Village adolescents were more subjectivist than their mothers and grandmothers. Sociodemographic characteristics representing greater exposure to diverse people and ideas accounted for generational differences. Both urban and rural adolescents tended towards subjectivist perspectives, and they did not differ. Parents' education levels emerged as the sociodemographic variables most consistently related to epistemic thinking. Epistemic thinking mediated the relationship between generation and gender role/cross-sex relation values. © 2014 International Union of Psychological Science.

Ego Depletion in Real-Time: An Examination of the Sequential-Task Paradigm.

PubMed

Arber, Madeleine M; Ireland, Michael J; Feger, Roy; Marrington, Jessica; Tehan, Joshua; Tehan, Gerald

2017-01-01

Current research into self-control that is based on the sequential task methodology is currently at an impasse. The sequential task methodology involves completing a task that is designed to tax self-control resources which in turn has carry-over effects on a second, unrelated task. The current impasse is in large part due to the lack of empirical research that tests explicit assumptions regarding the initial task. Five studies test one key, untested assumption underpinning strength (finite resource) models of self-regulation: Performance will decline over time on a task that depletes self-regulatory resources. In the aftermath of high profile replication failures using a popular letter-crossing task and subsequent criticisms of that task, the current studies examined whether depletion effects would occur in real time using letter-crossing tasks that did not invoke habit-forming and breaking, and whether these effects were moderated by administration type (paper and pencil vs. computer administration). Sample makeup and sizes as well as response formats were also varied across the studies. The five studies yielded a clear and consistent pattern of increasing performance deficits (errors) as a function of time spent on task with generally large effects and in the fifth study the strength of negative transfer effects to a working memory task were related to individual differences in depletion. These results demonstrate that some form of depletion is occurring on letter-crossing tasks though whether an internal regulatory resource reservoir or some other factor is changing across time remains an important question for future research.

Ego Depletion in Real-Time: An Examination of the Sequential-Task Paradigm

PubMed Central

Arber, Madeleine M.; Ireland, Michael J.; Feger, Roy; Marrington, Jessica; Tehan, Joshua; Tehan, Gerald

2017-01-01

Current research into self-control that is based on the sequential task methodology is currently at an impasse. The sequential task methodology involves completing a task that is designed to tax self-control resources which in turn has carry-over effects on a second, unrelated task. The current impasse is in large part due to the lack of empirical research that tests explicit assumptions regarding the initial task. Five studies test one key, untested assumption underpinning strength (finite resource) models of self-regulation: Performance will decline over time on a task that depletes self-regulatory resources. In the aftermath of high profile replication failures using a popular letter-crossing task and subsequent criticisms of that task, the current studies examined whether depletion effects would occur in real time using letter-crossing tasks that did not invoke habit-forming and breaking, and whether these effects were moderated by administration type (paper and pencil vs. computer administration). Sample makeup and sizes as well as response formats were also varied across the studies. The five studies yielded a clear and consistent pattern of increasing performance deficits (errors) as a function of time spent on task with generally large effects and in the fifth study the strength of negative transfer effects to a working memory task were related to individual differences in depletion. These results demonstrate that some form of depletion is occurring on letter-crossing tasks though whether an internal regulatory resource reservoir or some other factor is changing across time remains an important question for future research. PMID:29018390

Examining the effectiveness of consuming flour made from agronomically biofortified wheat (Zincol-2016/NR-421) for improving Zn status in women in a low-resource setting in Pakistan: study protocol for a randomised, double-blind, controlled cross-over trial (BiZiFED).

PubMed

Lowe, Nicola M; Khan, Muhammad Jaffar; Broadley, Martin R; Zia, Munir H; McArdle, Harry J; Joy, Edward J M; Ohly, Heather; Shahzad, Babar; Ullah, Ubaid; Kabana, Gul; Medhi, Rashid; Afridi, Mukhtiar Zaman

2018-04-17

Dietary zinc (Zn) deficiency is a global problem, particularly in low-income and middle-income countries where access to rich, animal-source foods of Zn is limited due to poverty. In Pakistan, Zn deficiency affects over 40% of the adult female population, resulting in suboptimal immune status and increased likelihood of complications during pregnancy. We are conducting a double-blind, randomised controlled feeding study with cross-over design in a low-resource setting in Pakistan. Households were provided with flour milled from genetically and agronomically biofortified grain (Zincol-2016/NR-421) or control grain (Galaxy-2013). Fifty households were recruited. Each household included a woman aged 16-49 years who is neither pregnant nor breastfeeding, and not currently consuming nutritional supplements. These women were the primary study participants. All households were provided with control flour for an initial 2-week baseline period, followed by an 8-week intervention period where 25 households receive biofortified flour (group A) and 25 households receive control flour (group B). After this 8-week period, groups A and B crossed over, receiving control and biofortified flour respectively for 8 weeks. Tissue (blood, hair and nails) have been collected from the women at five time points: baseline, middle and end of period 1, and middle and end of period 2. Ethical approval was granted from the lead university (reference no. STEMH 697 FR) and the collaborating institution in Pakistan. The final study methods (including any modifications) will be published in peer-reviewed journals, alongside the study outcomes on completion of the data analysis. In addition, findings will be disseminated to the scientific community via conference presentations and abstracts and communicated to the study participants through the village elders at an appropriate community forum. The trial has been registered with the ISRCTN registry, study ID ISRCTN83678069. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Dielectrophoretic spectroscopy using a microscopic electrode array

NASA Astrophysics Data System (ADS)

Kirmani, Syed Abdul Mannan; Gudagunti, Fleming Dackson; Velmanickam, Logeeshan; Nawarathna, Dharmakeerthi; Lima, Ivan T.

2017-02-01

Dielectrophoresis (DEP) is a commonly used technique in biomedical engineering to manipulate biomolecules. DEP is defined as the force acting on dielectric particles when they are exposed to non-uniform electric fields. DEP effect can be divided in three categories: positive (dielectric particles are attracted to the electrodes), negative, and zero force DEP. The cross-over frequency is the frequency in which the DEP force is equal to zero. The cross-over frequency depends on the conductivity and the permittivity of the particles and of the suspended medium. The DEP cross-over frequency has been utilized in detecting/quantifying biomolecules. A manual procedure is commonly used to estimate the cross-over frequency of biomolecules. Therefore, the accuracy of this detection method is significantly limited. To address this issue, we designed and tested an automated procedure to carry out DEP spectroscopy in dielectric particles dissolved in a biological buffer solution. Our method efficiently measures the effect of the DEP force through a live video feed from the microscope camera and performs real-time image processing. It records the change in the fluorescence emission as the system automatically scans the electric frequency of the function generator over a specified time interval. We demonstrated the effectiveness of the method by extracting the crossover frequencies and the DEP spectrum of polystyrene beads with blue color dye (1000 nm diameter) and green fluorescent polystyrene beads with 500 nm diameter using this procedure. This approach can lead to the development of a biosensor with significantly higher sensitivity than existing detection methods.

Tobacco use among designated air pollution victims and its association with lung function and respiratory symptoms: a retrospective cross-sectional study.

PubMed

Kotaki, Kenji; Senjyu, Hideaki; Tanaka, Takako; Yano, Yudai; Miyamoto, Naomi; Nishinakagawa, Tsuyoshi; Yanagita, Yorihide; Asai, Masaharu; Kozu, Ryo; Tabusadani, Mitsuru; Sawai, Terumitsu; Honda, Sumihisa

2014-07-31

We sought to elucidate the long-term association of tobacco use and respiratory health in designated pollution victims with and without obstructive pulmonary defects. A retrospective cross-sectional study. The register of pollution victims in Kurashiki, Japan. 730 individuals over 65 years of age previously diagnosed with pollution-related respiratory disease. Patients were classified into four groups according to their smoking status and whether they had obstructive pulmonary disease. We then compared the prevalence of respiratory symptoms and lung function over time between groups. Spirometry was performed and a respiratory health questionnaire completed in the same season each year for up to 30 years. Rates of smoking and respiratory disease were high in our sample. Although respiratory function in non-smoking patients did not completely recover, the annual rate of change in lung function was within the normal range (p<0.01). However, smokers had worse lung function and were more likely to report more severe pulmonary symptoms (p<0.01). Patients' respiratory function did not fully recover despite improved air quality. Our results suggest that, in the context of exposure to air pollution, tobacco use causes additional loss of lung function and exacerbates respiratory symptoms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Acetylsalicylic acid does not reduce the intraocular pressure variation in ocular hypertension or glaucoma.

PubMed

Lindén, C; Alm, A

2000-03-01

The purpose of this study was to measure if intraocular pressure (IOP) and IOP variations in patients with ocular hypertension and glaucoma are decreased by acetylsalicylic acid (ASA). The hypothesis to be tested was that short-term fluctuations in the IOP are caused by breaks of the inner wall of Schlemm's canal that are repaired by platelets inducing a cycle of breaks and repair. Furthermore, prostaglandins affect uveoscleral outflow and ASA inhibits prostaglandin biosynthesis and platelet aggregation. This implies that ASA may have complex effects on the IOP and its variations.In 28 patients with ocular hypertension or glaucoma the IOP was measured seven times during 2 hr on two succeeding days. Five hundred mg ASA or placebo was administrated orally in a masked fashion 15 hr prior to the second session. After wash-out, this procedure was repeated with a cross-over design. The same study outline was used in 28 glaucoma patients except for the cross-over design. There were no statistically significant differences in the mean IOP or in the IOP variations between the placebo treated and the ASA treated eyes in either group, and there were no significant differences between the day before and after treatment in any group. The results suggest that ASA does not affect IOP variations in a clinically significant way and that a single dose of ASA has no significant effect on mean IOP. Copyright 2000 Academic Press.

Test-retest reliability and cross validation of the functioning everyday with a wheelchair instrument.

PubMed

Mills, Tamara L; Holm, Margo B; Schmeler, Mark

2007-01-01

The purpose of this study was to establish the test-retest reliability and content validity of an outcomes tool designed to measure the effectiveness of seating-mobility interventions on the functional performance of individuals who use wheelchairs or scooters as their primary seating-mobility device. The instrument, Functioning Everyday With a Wheelchair (FEW), is a questionnaire designed to measure perceived user function related to wheelchair/scooter use. Using consumer-generated items, FEW Beta Version 1.0 was developed and test-retest reliability was established. Cross-validation of FEW Beta Version 1.0 was then carried out with five samples of seating-mobility users to establish content validity. Based on the content validity study, FEW Version 2.0 was developed and administered to seating-mobility consumers to examine its test-retest reliability. FEW Beta Version 1.0 yielded an intraclass correlation coefficient (ICC) Model (3,k) of .92, p < .001, and the content validity results revealed that FEW Beta Version 1.0 captured 55% of seating-mobility goals reported by consumers across five samples. FEW Version 2.0 yielded ICC(3,k) = .86, p < .001, and captured 98.5% of consumers' seating-mobility goals. The cross-validation study identified new categories of seating-mobility goals for inclusion in FEW Version 2.0, and the content validity of FEW Version 2.0 was confirmed. FEW Beta Version 1.0 and FEW Version 2.0 were highly stable in their measurement of participants' seating-mobility goals over a 1-week interval.

The high-resolution cross-dispersed echelle white-pupil spectrometer of the McDonald Observatory 2.7-m telescope

NASA Technical Reports Server (NTRS)

Tull, Robert G.; Macqueen, Phillip J.; Sneden, Christopher; Lambert, David L.

1995-01-01

A new high-resolution cross-dispersed echelle spectrometer has been installed at the coude focus of the McDonald Observatory 2.7-m telescope. Its primary goal was simultaneously to gather spectra over as much of the spectral range 3400 A to 1 micrometer as practical, at a resolution R identical with lambda/Delta lambda which approximately = 60,000 with signal-to-noise ratio of approximately 100 for stars down to magnitude 11, using 1-h exposures. In the instrument as built, two exposures are all that are needed to cover the full range. Featuring a white-pupil design, fused silica prism cross disperser, and folded Schmidt camera with a Tektronix 2048x2048 CCD used at either of two foci, it has been in regularly scheduled operation since 1992 April. Design details and performance are described.

A probabilistic methodology for radar cross section prediction in conceptual aircraft design

NASA Astrophysics Data System (ADS)

Hines, Nathan Robert

System effectiveness has increasingly become the prime metric for the evaluation of military aircraft. As such, it is the decision maker's/designer's goal to maximize system effectiveness. Industry and government research documents indicate that all future military aircraft will incorporate signature reduction as an attempt to improve system effectiveness and reduce the cost of attrition. Today's operating environments demand low observable aircraft which are able to reliably take out valuable, time critical targets. Thus it is desirable to be able to design vehicles that are balanced for increased effectiveness. Previous studies have shown that shaping of the vehicle is one of the most important contributors to radar cross section, a measure of radar signature, and must be considered from the very beginning of the design process. Radar cross section estimation should be incorporated into conceptual design to develop more capable systems. This research strives to meet these needs by developing a conceptual design tool that predicts radar cross section for parametric geometries. This tool predicts the absolute radar cross section of the vehicle as well as the impact of geometry changes, allowing for the simultaneous tradeoff of the aerodynamic, performance, and cost characteristics of the vehicle with the radar cross section. Furthermore, this tool can be linked to a campaign theater analysis code to demonstrate the changes in system and system of system effectiveness due to changes in aircraft geometry. A general methodology was developed and implemented and sample computer codes applied to prototype the proposed process. Studies utilizing this radar cross section tool were subsequently performed to demonstrate the capabilities of this method and show the impact that various inputs have on the outputs of these models. The F/A-18 aircraft configuration was chosen as a case study vehicle to perform a design space exercise and to investigate the relative impact of shaping parameters on radar cross section. Finally, two unique low observable configurations were analyzed to examine the impact of shaping for stealthiness.

RMS: a platform for managing cross-disciplinary and multi-institutional research project collaboration.

PubMed

Luo, Jake; Apperson-Hansen, Carolyn; Pelfrey, Clara M; Zhang, Guo-Qiang

2014-11-30

Cross-institutional cross-disciplinary collaboration has become a trend as researchers move toward building more productive and innovative teams for scientific research. Research collaboration is significantly changing the organizational structure and strategies used in the clinical and translational science domain. However, due to the obstacles of diverse administrative structures, differences in area of expertise, and communication barriers, establishing and managing a cross-institutional research project is still a challenging task. We address these challenges by creating an integrated informatics platform to reduce the barriers to biomedical research collaboration. The Request Management System (RMS) is an informatics infrastructure designed to transform a patchwork of expertise and resources into an integrated support network. The RMS facilitates investigators' initiation of new collaborative projects and supports the management of the collaboration process. In RMS, experts and their knowledge areas are categorized and managed structurally to provide consistent service. A role-based collaborative workflow is tightly integrated with domain experts and services to streamline and monitor the life-cycle of a research project. The RMS has so far tracked over 1,500 investigators with over 4,800 tasks. The research network based on the data collected in RMS illustrated that the investigators' collaborative projects increased close to 3 times from 2009 to 2012. Our experience with RMS indicates that the platform reduces barriers for cross-institutional collaboration of biomedical research projects. Building a new generation of infrastructure to enhance cross-disciplinary and multi-institutional collaboration has become an important yet challenging task. In this paper, we share the experience of developing and utilizing a collaborative project management system. The results of this study demonstrate that a web-based integrated informatics platform can facilitate and increase research interactions among investigators.

Metabolomics: A Window for Understanding Long Term Physical Consequences of Distrubed Sleep and Hypothalamic Pituitary Adrenal Function in Posttraumatic Stress

DTIC Science & Technology

2017-09-01

performed on pre -collected plasma samples from a study that had a two- group cross-sectional design in which main comparisons were with medically...controls. Approach Metabolomic analysis will be performed on pre -collected plasma samples from a study that had a two- group cross-sectional design in...disturbances, and health. Metabolomic analysis will be performed on pre -collected plasma samples from a study that had a two- group cross-sectional

Injury, disability and access to care in Rwanda: results of a nationwide cross-sectional population study.

PubMed

Petroze, Robin T; Joharifard, Shahrzad; Groen, Reinou S; Niyonkuru, Francine; Ntaganda, Edmond; Kushner, Adam L; Guterbock, Thomas M; Kyamanywa, Patrick; Calland, J Forrest

2015-01-01

Disparities in access to quality injury care are a growing concern worldwide, with over 90 % of global injury-related morbidity and mortality occurring in low-income countries. We describe the use of a survey tool that evaluates the prevalence of surgical conditions at the population level, with a focus on the burden of traumatic injuries, subsequent disabilities, and barriers to injury care in Rwanda. The Surgeons OverSeas Assessment of Surgical Need (SOSAS) tool is a cross-sectional, cluster-based population survey designed to measure conditions that may necessitate surgical consultation or intervention. Questions are structured anatomically and designed around a representative spectrum of surgical conditions. Households in Rwanda were sampled using two-stage cluster sampling, and interviews were conducted over a one-month period in 52 villages nationwide, with representation of all 30 administrative districts. Injury-related results were descriptively analyzed and population-weighted by age and gender. A total of 1,627 households (3,175 individuals) were sampled; 1,185 lifetime injury-related surgical conditions were reported, with 38 % resulting in some form of perceived disability. Of the population, 27.4 % had ever had a serious injury-related condition, with 2.8 % having an injury-related condition at the time of interview. Over 30 % of household deaths in the previous year may have been surgically treatable, but only 4 % were injury-related. Determining accurate injury and disability burden is crucial to health system planning in low-income countries. SOSAS is a useful survey for determining injury epidemiology at the community level, which can in turn help to plan prevention efforts and optimize provision of care.

Longitudinal Theory of Mind (ToM) Development From Preschool to Adolescence With and Without ToM Delay.

PubMed

Peterson, Candida C; Wellman, Henry M

2018-04-16

Longitudinal tracking of 107 three- to-thirteen-year-olds in a cross-sequential design showed a 6-step theory of mind (ToM) sequence identified by a few past cross-sectional studies validly depicted longitudinal ToM development from early to middle childhood for typically developing (TD) children and those with ToM delays owing to deafness or autism. Substantively, all groups showed ToM progress throughout middle childhood. Atypical development was more extended and began and ended at lower levels than for TD children. Yet most children in all groups progressed over the study's mean 1.5 years. Findings help resolve theoretical debates about ToM development for children with and without delay and gain strength and weight via their applicability to three disparate groups varying in ToM timing and sequencing. © 2018 Society for Research in Child Development.

The Effect of Agave tequilana Weber Inulin on Postprandial Ghrelin Concentration in Obese Patients.

PubMed

Contreras-Haro, Betsabe; Robles-Cervantes, Jose A; Gonzalez-Ortiz, Manuel; Martinez-Abundis, Esperanza; Espinel-Bermudez, Claudia; Gallegos-Arreola, Martha P; Morgado-Castillo, Karina C

2017-02-01

This study was performed to investigate the effect of Agave tequilana Weber inulin on postprandial ghrelin levels in obese patients. A randomized, double-blind, cross-over design was performed. A total of 14 patients were allocated into two groups: one group received a drink that contained 500 mL lemon water, 24 g of A. tequilana Weber inulin, and 75 g glucose and the other group received a placebo drink with 500 mL lemon drink and 75 g of glucose. After a 7-day washout period, the groups were crossed. The primary outcome measure was postprandial ghrelin levels between minute 240 and minute 270. A. tequilana Weber inulin did not change postprandial ghrelin concentration in obese patients.

Bioavailability of sulforaphane from two broccoli sprout beverages: Results of a short term, cross-over clinical trial in Qidong, China

PubMed Central

Egner, Patricia A.; Chen, Jian Guo; Wang, Jin Bing; Wu, Yan; Sun, Yan; Lu, Jian Hua; Zhu, Jian; Zhang, Yong Hui; Chen, Yong Sheng; Friesen, Marlin D.; Jacobson, Lisa P.; Muñoz, Alvaro; Ng, Derek; Qian, Geng Sun; Zhu, Yuan Rong; Chen, Tao Yang; Botting, Nigel P.; Zhang, Qingzhi; Fahey, Jed W.; Talalay, Paul; Groopman, John D; Kensler, Thomas W.

2011-01-01

One of several challenges in design of clinical chemoprevention trials is the selection of the dose, formulation and dose schedule of the intervention agent. Therefore, a cross-over clinical trial was undertaken to compare the bioavailability and tolerability of sulforaphane from two of broccoli sprout-derived beverages: one glucoraphanin-rich (GRR) and the other sulforaphane-rich (SFR). Sulforaphane was generated from glucoraphanin contained in GRR by gut microflora or formed by treatment of GRR with myrosinase from daikon (Raphanus sativus) sprouts to provide SFR. Fifty healthy, eligible participants were requested to refrain from crucifer consumption and randomized into two treatment arms. The study design was as follows: 5-day run-in period, 7-day administration of beverages, 5-day washout period, and 7-day administration of the opposite intervention. Isotope dilution mass spectrometry was used to measure levels of glucoraphanin, sulforaphane and sulforaphane thiol conjugates in urine samples collected daily throughout the study. Bioavailability, as measured by urinary excretion of sulforaphane and its metabolites (in approximately 12 hour collections after dosing), was substantially greater with the SFR (mean = 70%) than with GRR (mean = 5%) beverages. Interindividual variability in excretion was considerably lower with SFR than GRR beverage. Elimination rates were considerably slower with GRR allowing for achievement of steady state dosing as opposed to bolus dosing with SFR. Optimal dosing formulations in future studies should consider blends of sulforaphane and glucoraphanin as SFR and GRR mixtures to achieve peak concentrations for activation of some targets and prolonged inhibition of others implicated in the protective actions of sulforaphane. PMID:21372038

CAGE IIIA Distributed Simulation Design Methodology

DTIC Science & Technology

2014-05-01

2 VHF Very High Frequency VLC Video LAN Codec – an Open-source cross-platform multimedia player and framework VM Virtual Machine VOIP Voice Over...Implementing Defence Experimentation (GUIDEx). The key challenges for this methodology are with understanding how to: • design it o define the...operation and to be available in the other nation’s simulations. The challenge for the CAGE campaign of experiments is to continue to build upon this

A randomised cross-over pharmacokinetic bioavailability study of synthetic versus kiwifruit-derived vitamin C.

PubMed

Carr, Anitra C; Bozonet, Stephanie M; Vissers, Margreet C M

2013-11-11

Kiwifruit are a rich source of vitamin C and also contain numerous phytochemicals, such as flavonoids, which may influence the bioavailability of kiwifruit-derived vitamin C. The aim of this study was to compare the relative bioavailability of synthetic versus kiwifruit-derived vitamin C using a randomised cross-over pharmacokinetic study design. Nine non-smoking males (aged 18-35 years) received either a chewable tablet (200 mg vitamin C) or the equivalent dose from gold kiwifruit (Actinidia chinensis var. Sungold). Fasting blood and urine were collected half hourly to hourly over the eight hours following intervention. The ascorbate content of the plasma and urine was determined using HPLC with electrochemical detection. Plasma ascorbate levels increased from 0.5 h after the intervention (P = 0.008). No significant differences in the plasma time-concentration curves were observed between the two interventions (P = 0.645). An estimate of the total increase in plasma ascorbate indicated complete uptake of the ingested vitamin C tablet and kiwifruit-derived vitamin C. There was an increase in urinary ascorbate excretion, relative to urinary creatinine, from two hours post intervention (P < 0.001). There was also a significant difference between the two interventions, with enhanced ascorbate excretion observed in the kiwifruit group (P = 0.016). Urinary excretion was calculated as ~40% and ~50% of the ingested dose from the vitamin C tablet and kiwifruit arms, respectively. Overall, our pharmacokinetic study has shown comparable relative bioavailability of kiwifruit-derived vitamin C and synthetic vitamin C.

Effects of 7.5% CO2 challenge in generalized anxiety disorder.

PubMed

Seddon, Kate; Morris, Kelly; Bailey, Jayne; Potokar, John; Rich, Ann; Wilson, Sue; Bettica, Paolo; Nutt, David J

2011-01-01

We have previously developed a putative model of generalized anxiety disorder in healthy volunteers using a 20-minute 7.5% carbon dioxide (CO(2)) inhalation challenge. The aim of this study was to validate the 7.5% CO(2) paradigm by assessing its effects in patients with generalized anxiety disorder in a test-retest design. Twelve medication-free generalized anxiety disorder patients attended our lab for two study days. On each study day placebo (compressed air) and 7.5% CO(2) mixture were randomly administered over 20 min, at least 30 min apart, in a single blind, randomized, placebo-controlled cross-over design. Subjective ratings, cardiovascular measures and cortisol levels were collected throughout. CO(2) challenge significantly increased ratings for anxiety and other subjective symptoms associated with generalized anxiety disorder, compared with air. It also significantly increased systolic blood pressure on day 2, indicating increased autonomic arousal. There was no change between the two test days in mean anxiety rating scores, and there also appeared to be a correlation for individual scores on a number of the subjective measures. In conclusion, 20 min of 7.5% CO(2) gas inhalation increases anxiety responses in patients with generalized anxiety disorder, and this is reliable over time.

77 FR 47924 - Determinations Concerning Illnesses Discussed in National Academy of Sciences Report: Veterans...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-10

... significant increased prevalence of hypertension. The cross-sectional design of this study (in which subjects.... This study was also cross-sectional in design, limiting its ability to quantify risk, establish a... for significant confounders or by other methodological concerns. Accordingly, [[Page 47927

Designing and Delivering Cross-Cultural Instruction.

ERIC Educational Resources Information Center

Ben-Yoseph, Miriam

A course on management in a cross-cultural environment was designed to address dilemmas and opportunities that individuals might encounter in work or study. The course attracted students with a broad variety of backgrounds. A main textbook was supplemented with readings, guest lectures, and a variety of class activities including case studies,…

Parametric Weight Study of Cryogenic Metallic Tanks for the ``Bimodal'' NTR Mars Vehicle Concept

NASA Astrophysics Data System (ADS)

Kosareo, Daniel N.; Roche, Joseph M.

2006-01-01

A parametric weight assessment of large cryogenic metallic tanks was conducted using the design optimization capabilities in the ANSYS ® finite element analysis code. This analysis was performed to support the sizing of a ``bimodal'' nuclear thermal rocket (NTR) Mars vehicle concept developed at the NASA Glenn Research Center. The tank design study was driven by two load conditions: an in-line, ``Shuttle-derived'' heavy-lift launch with the tanks filled and pressurized, and a burst-test pressure. The main tank structural arrangement is a state-of-the art metallic construction which uses an aluminum-lithium alloy stiffened internally with a ring and stringer framework. The tanks must carry liquid hydrogen in separate launches to orbit where all vehicle components will dock and mate. All tank designs stayed within the available mass and payload volume limits of both the in-line heavy lift and Shuttle derived launch vehicles. Weight trends were developed over a range of tank lengths with varying stiffener cross-sections and tank wall thicknesses. The object of this parametric study was to verify that the proper mass was allocated for the tanks in the overall vehicle sizing model. This paper summarizes the tank weights over a range of tank lengths.

Tough and deformable glasses with bioinspired cross-ply architectures.

PubMed

Yin, Zhen; Dastjerdi, Ahmad; Barthelat, Francois

2018-05-15

Glasses are optically transparent, hard materials that have been in sustained demand and usage in architectural windows, optical devices, electronics and solar panels. Despite their outstanding optical qualities and durability, their brittleness and low resistance to impact still limits wider applications. Here we present new laminated glass designs that contain toughening cross-ply architectures inspired from fish scales and arthropod cuticles. This seemingly minor enrichment completely transforms the way laminated glass deforms and fractures, and it turns a traditionally brittle material into a stretchy and tough material with little impact on surface hardness and optical quality. Large ply rotation propagates over large volumes, and localization is delayed in tension, even if a strain softening interlayer is used, in a remarkable mechanism which is generated by the kinematics of the plies and geometrical hardening. Compared to traditional laminated glass which degrades significantly in performance when damaged, our cross-ply architecture glass is damage-tolerant and 50 times tougher in energy terms. Despite the outstanding optical qualities and durability of glass, its brittleness and low resistance to impact still limits its wider application. Here we present new laminated glass designs that contain toughening cross-ply architectures inspired from fish scales and arthropod cuticles. Enriching laminated designs with crossplies completely transforms the material deforms and fractures, and turns a traditionally brittle material into a stretchy and tough material - with little impact on surface hardness and optical quality. Large ply rotation propagates over large volumes and localization is delayed in tension because of a remarkable and unexpected geometrical hardening effect. Compared to traditional laminated glass which degrades significantly in performance when damaged, our cross-ply architecture glass is damage-tolerant and it is 50 times tougher in energy terms. Our glass-based, transparent material is highly innovative and it is the first of its kind. We believe it will have impact in broad range of applications in construction, coatings, chemical engineering, electronics, photovoltaics. Copyright © 2018. Published by Elsevier Ltd.

Shaping the Development of Prejudice: Latent Growth Modeling of the Influence of Social Dominance Orientation on Outgroup Affect in Youth.

PubMed

Bratt, Christopher; Sidanius, Jim; Sheehy-Skeffington, Jennifer

2016-12-01

Social dominance orientation (SDO) has been theorized as a stable, early-emerging trait influencing outgroup evaluations, a view supported by evidence from cross-sectional and two-wave longitudinal research. Yet, the limitations of identifying causal paths with cross-sectional and two-wave designs are increasingly being acknowledged. This article presents the first use of multi-wave data to test the over-time relationship between SDO and outgroup affect among young people. We use cross-lagged and latent growth modeling (LGM) of a three-wave data set employing Norwegian adolescents (over 2 years, N = 453) and a five-wave data set with American university students (over 4 years, N = 748). Overall, SDO exhibits high temporal rank-order stability and predicts changes in outgroup affect. This research represents the strongest test to date of SDO's role as a stable trait that influences the development of prejudice, while highlighting LGM as a valuable tool for social and political psychology. © 2016 by the Society for Personality and Social Psychology, Inc.

A longitudinal study of an intervention to improve road safety climate: climate as an organizational boundary spanner.

PubMed

Naveh, Eitan; Katz-Navon, Tal

2015-01-01

This study presents and tests an intervention to enhance organizational climate and expands existing conceptualization of organizational climate to include its influence on employee behaviors outside the organization's physical boundaries. In addition, by integrating the literatures of climate and work-family interface, the study explored climate spillover and crossover from work to the home domain. Focusing on an applied practical problem within organizations, we investigated the example of road safety climate and employees' and their families' driving, using a longitudinal study design of road safety intervention versus control groups. Results demonstrated that the intervention increased road safety climate and decreased the number of traffic violation tickets and that road safety climate mediated the relationship between the intervention and the number of traffic violation tickets. Road safety climate spilled over to the family domain but did not cross over to influence family members' driving. (c) 2015 APA, all rights reserved.

Perfectionism, Procrastination, and Psychological Distress

ERIC Educational Resources Information Center

Rice, Kenneth G.; Richardson, Clarissa M. E.; Clark, Dustin

2012-01-01

Using a cross-panel design and data from 2 successive cohorts of college students ( N = 357), we examined the stability of maladaptive perfectionism, procrastination, and psychological distress across 3 time points within a college semester. Each construct was substantially stable over time, with procrastination being especially stable. We also…

Sentence Context Prevails Over Word Association in Aphasia Patients with Spared Comprehension: Evidence from N400 Event-Related Potential

PubMed Central

Khachatryan, Elvira; De Letter, Miet; Vanhoof, Gertie; Goeleven, Ann; Van Hulle, Marc M.

2017-01-01

Behavioral and event-related potential (ERP) studies on aphasia patients showed that lexical information is not lost but rather its integration into the working context is hampered. Studies have been conducted on the processing of sentence-level information (meaningful versus meaningless) and of word-level information (related versus unrelated) in aphasia patients, but we are not aware of any study that assesses the relationship between the two. In healthy subjects the processing of a single word in a sentence context has been studied using the N400 ERP. It was shown that, even when there is only a weak expectation of a final word in a sentence, this expectation will dominate word relatedness. In order to study the effect of semantic relatedness between words in sentence processing in aphasia patients, we conducted a crossed-design ERP study, crossing the factors of word relatedness and sentence congruity. We tested aphasia patients with mild to minimum comprehension deficit and healthy young and older (age-matched with our patients) controls on a semantic anomaly judgment task when simultaneously recording EEG. Our results show that our aphasia patient’s N400 amplitudes in response to the sentences of our crossed-design study were similar to those of our age-matched healthy subjects. However, we detected an increase in the N400 ERP latency in those patients, indicating a delay in the integration of the new word into the working context. Additionally, we observed a positive correlation between comprehension level of those patients and N400 effect in response to meaningful sentences without word relatedness contrasted to meaningless sentences without word relatedness. PMID:28119590

Within- and between-session replicability of cognitive brain processes: An MEG study with an N-back task.

PubMed

Ahonen, L; Huotilainen, M; Brattico, E

2016-05-01

In the vast majority of electrophysiological studies on cognition, participants are only measured once during a single experimental session. The dearth of studies on test-retest reliability in magnetoencephalography (MEG) within and across experimental sessions is a preventing factor for longitudinal designs, imaging genetics studies, and clinical applications. From the recorded signals, it is not straightforward to draw robust and steady indices of brain activity that could directly be used in exploring behavioral effects or genetic associations. To study the variations in markers associated with cognitive functions, we extracted three event-related field (ERF) features from time-locked global field power (GFP) epochs using MEG while participants were performing a numerical N-back task in four consecutive measurements conducted during two different days separated by two weeks. We demonstrate that the latency of the M170, a neural correlate associated with cognitive functions such as working memory, was a stable parameter and did not show significant variations over time. In addition, the M170 peak amplitude and the mean amplitude of late positive component (LPP) also expressed moderate-to-strong reliability across multiple measures over time over many sensor spaces and between participants. The M170 amplitude varied more significantly between the measurements in some conditions but showed consistency over the participants over time. In addition we demonstrated significant correlation with the M170 and LPP parameters and cognitive load. The results are in line with the literature showing less within-subject fluctuation for the latency parameters and more consistency in between-subject comparisons for amplitude based features. The within-subject consistency was apparent also with longer delays between the measurements. We suggest that with a few limitations the ERF features show sufficient reliability and stability for longitudinal research designs and clinical applications for cognitive functions in single as well as cross-subject designs. Copyright © 2016 Elsevier Inc. All rights reserved.

Sampling pig farms at the abattoir in a cross-sectional study - Evaluation of a sampling method.

PubMed

Birkegård, Anna Camilla; Halasa, Tariq; Toft, Nils

2017-09-15

A cross-sectional study design is relatively inexpensive, fast and easy to conduct when compared to other study designs. Careful planning is essential to obtaining a representative sample of the population, and the recommended approach is to use simple random sampling from an exhaustive list of units in the target population. This approach is rarely feasible in practice, and other sampling procedures must often be adopted. For example, when slaughter pigs are the target population, sampling the pigs on the slaughter line may be an alternative to on-site sampling at a list of farms. However, it is difficult to sample a large number of farms from an exact predefined list, due to the logistics and workflow of an abattoir. Therefore, it is necessary to have a systematic sampling procedure and to evaluate the obtained sample with respect to the study objective. We propose a method for 1) planning, 2) conducting, and 3) evaluating the representativeness and reproducibility of a cross-sectional study when simple random sampling is not possible. We used an example of a cross-sectional study with the aim of quantifying the association of antimicrobial resistance and antimicrobial consumption in Danish slaughter pigs. It was not possible to visit farms within the designated timeframe. Therefore, it was decided to use convenience sampling at the abattoir. Our approach was carried out in three steps: 1) planning: using data from meat inspection to plan at which abattoirs and how many farms to sample; 2) conducting: sampling was carried out at five abattoirs; 3) evaluation: representativeness was evaluated by comparing sampled and non-sampled farms, and the reproducibility of the study was assessed through simulated sampling based on meat inspection data from the period where the actual data collection was carried out. In the cross-sectional study samples were taken from 681 Danish pig farms, during five weeks from February to March 2015. The evaluation showed that the sampling procedure was reproducible with results comparable to the collected sample. However, the sampling procedure favoured sampling of large farms. Furthermore, both under-sampled and over-sampled areas were found using scan statistics. In conclusion, sampling conducted at abattoirs can provide a spatially representative sample. Hence it is a possible cost-effective alternative to simple random sampling. However, it is important to assess the properties of the resulting sample so that any potential selection bias can be addressed when reporting the findings. Copyright © 2017 Elsevier B.V. All rights reserved.

Cross/bar polymer electro-optic routing switch with broadband flatting spectral response over 130 nm: Principle, design and analysis

NASA Astrophysics Data System (ADS)

Zheng, Chuan-Tao; Zheng, Li-Hua; Luo, Qian-Qian; Liang, Lei; Ma, Chun-Sheng; Zhang, Da-Ming

2013-05-01

A novel non-resonance 2×2 polymer electro-optic (EO) switch with flatting spectral response is proposed by employing two-section reversed active Mach-Zehnder interferometers (MZIs), a passive middle directional coupler (M-DC) and two passive phase generating couplers (PGCs). Two crosstalk compensations are performed by optimizing the PGCs to broaden the spectrum under bar-state and optimizing the two active MZIs to broaden the spectrum under cross-state. The bar-state and cross-state voltages are 0 and ±4 V, respectively, with the two optimized MZI EO region lengths of 4068 and 5941 μm. Sufficiently considering wavelength dispersion of material and waveguide, a wide spectrum over 130 nm (1473-1603 nm) is achieved for dropping the crosstalk below -30 dB, and within this range, an insertion loss of 1.8-12.3 dB is observed. Under the same crosstalk level, this spectrum is over 2 times of that of the traditional 2×2 MZI switch (60 nm) based on the same materials. This broadband 2×2 switch is more attractive than our previously reported broadband 1×1 switch due to cross/bar routing operations other than simple ON/OFF functions.

Calibration Matters: Advances in Strapdown Airborne Gravimetry

NASA Astrophysics Data System (ADS)

Becker, D.

2015-12-01

Using a commercial navigation-grade strapdown inertial measurement unit (IMU) for airborne gravimetry can be advantageous in terms of cost, handling, and space consumption compared to the classical stable-platform spring gravimeters. Up to now, however, large sensor errors made it impossible to reach the mGal-level using such type IMUs as they are not designed or optimized for this kind of application. Apart from a proper error-modeling in the filtering process, specific calibration methods that are tailored to the application of aerogravity may help to bridge this gap and to improve their performance. Based on simulations, a quantitative analysis is presented on how much IMU sensor errors, as biases, scale factors, cross couplings, and thermal drifts distort the determination of gravity and the deflection of the vertical (DOV). Several lab and in-field calibration methods are briefly discussed, and calibration results are shown for an iMAR RQH unit. In particular, a thermal lab calibration of its QA2000 accelerometers greatly improved the long-term drift behavior. Latest results from four recent airborne gravimetry campaigns confirm the effectiveness of the calibrations applied, with cross-over accuracies reaching 1.0 mGal (0.6 mGal after cross-over adjustment) and DOV accuracies reaching 1.1 arc seconds after cross-over adjustment.

Ion profiling in an ambient drift tube-ion mobility spectrometer using a high pixel density linear array detector IonCCD.

PubMed

Davila, Stephen J; Hadjar, Omar; Eiceman, Gary A

2013-07-16

A linear pixel-based detector array, the IonCCD, is characterized for use under ambient conditions with thermal (<1 eV) positive ions derived from purified air and a 10 mCi (63)Ni foil. The IonCCD combined with a drift tube-ion mobility spectrometer permitted the direct detection of gas phase ions at atmospheric pressure and confirmed a limit of detection of 3000 ions/pixel/frame established previously in both the keV (1-2 keV) and the hyper-thermal (10-40 eV) regimes. Results demonstrate the "broad-band" application of the IonCCD over 10(5) orders in ion energy and over 10(10) in operating pressure. The Faraday detector of a drift tube for an ion mobility spectrometer was replaced with the IonCCD providing images of ion profiles over the cross-section of the drift tube. Patterns in the ion profiles were developed in the drift tube cross-section by control of electric fields between wires of Bradbury Nielson and Tyndall Powell shutter designs at distances of 1-8 cm from the detector. Results showed that ion beams formed in wire sets, retained their shape with limited mixing by diffusion and Coulombic repulsion. Beam broadening determined as 95 μm/cm for hydrated protons in air with moisture of ~10 ppmv. These findings suggest a value of the IonCCD in further studies of ion motion and diffusion of thermalized ions, enhancing computational results from simulation programs, and in the design or operation of ion mobility spectrometers.

Spacelab Accomplishments Forum 4

NASA Technical Reports Server (NTRS)

Emond, J. (Editor); Bennet, N. (Compiler); McCauley, D. (Compiler); Murphy, K. (Compiler); Baugher, Charles R. (Technical Monitor)

1999-01-01

The Spacelab Module, exposed platforms, and supporting instrumentation were designed and developed by the European Space Agency to house advanced experiments inside the Space Shuttle cargo bay. The Spacelab program has hosted a cross-disciplinary research agenda over a 17-year flight history. Several variations of Spacelab were used to host payloads for almost every space research discipline that NASA pursues-life sciences, microgravity research, space sciences, and earth observation studies. After seventeen years of flight, Spacelab modules, pallets, or variations thereof flew on the Shuttle 36 times for a total of 375 flight days.

Immediate Effects of Ankle Balance Taping with Kinesiology Tape for Amateur Soccer Players with Lateral Ankle Sprain: A Randomized Cross-Over Design

PubMed Central

Kim, Myoung Kwon; Shin, Young Jun

2017-01-01

Background The objective of this study was to investigate the immediate effect on gait function when ankle balance taping is applied to amateur soccer players with lateral ankle sprain. Material/Methods A cross-over randomized design was used. Twenty-two soccer players with an ankle sprain underwent 3 interventions in a random order. Subjects were randomly assigned to ankle balance taping, placebo taping, and no taping groups. The assessment was performed using the GAITRite portable walkway system, which records the location and timing of each footfall during ambulation. Results Significant differences were found in the velocity, step length, stride length, and H-H base support among the 3 different taping methods (p<0.05). The ankle balance taping group showed significantly greater velocity, step length, and stride length in comparison to the placebo and no taping group. The ankle balance taping group showed a statistically significant decrease (p<0.05) in the H-H base support compared to the placebo and no taping groups, and the placebo group showed significantly greater velocity in comparison to the no taping group (p<0.05). Conclusions We conclude that ankle balance taping that uses kinesiology tape instantly increased the walking ability of amateur soccer players with lateral ankle sprain. Therefore, ankle balance taping is a useful alternative to prevent and treat ankle sprain of soccer players. PMID:29158472

Design, Analysis, and On-Sun Evaluation of Reflective Strips Under Controlled Buckling

NASA Technical Reports Server (NTRS)

Jaworske, Donald A.; Sechkar, Edward A.; Colozza, Anthony J.

2014-01-01

Solar concentrators are envisioned for use in a variety of space-based applications, including applications involving in situ resource utilization. Identifying solar concentrators that minimize mass and cost are of great interest, especially since launch cost is driven in part by the mass of the payload. Concentrators must also be able to survive the wide temperature excursions on the lunar surface. Identifying smart structures which compensate for changes in concentrator geometry brought about by temperature extremes are of interest. Some applications may benefit from the ability to change the concentrators focal pattern at will. This paper addresses a method of designing a single reflective strip to produce a desired focal pattern through the use of controlled buckling. Small variations in the cross section over the length of the reflective strip influence the distribution of light in the focal region. A finite element method of analysis is utilized here which calculates the curve produced for a given strip cross section and axial load. Varying axial force and strip cross section over the length of the reflective strip provide a means of optimizing ray convergence in the focal region. Careful selection of a tapered cross section yields a reflective strip that approximates a parabola. An array of reflective strips under controlled buckling produces a light weight concentrator and adjustments in the compression of individual strips provide a means of compensating for temperature excursions or changing the focal pattern at will.

Design, Analysis, and On-Sun Evaluation of Reflective Strips Under Controlled Buckling

NASA Technical Reports Server (NTRS)

Jaworske, D. A.; Sechkar, E. A.; Colozza, A. J.

2014-01-01

Solar concentrators are envisioned for use in a variety of space-based applications, including applications involving in situ resource utilization. Identifying solar concentrators that minimize mass and cost are of great interest, especially since launch cost is driven in part by the mass of the payload. Concentrators must also be able to survive the wide temperature excursions on the lunar surface. Identifying smart structures which compensate for changes in concentrator geometry brought about by temperature extremes are of interest. Some applications may benefit from the ability to change the concentrator's focal pattern at will. This paper addresses a method of designing a single reflective strip to produce a desired focal pattern through the use of controlled buckling. Small variations in the cross section over the length of the reflective strip influence the distribution of light in the focal region. A finite element method of analysis is utilized here which calculates the curve produced for a given strip cross section and axial load. Varying axial force and strip cross section over the length of the reflective strip provide a means of optimizing ray convergence in the focal region. Careful selection of a tapered cross section yields a reflective strip that approximates a parabola. An array of reflective strips under controlled buckling produces a light weight concentrator and adjustments in the compression of individual strips provide a means of compensating for temperature excursions or changing the focal pattern at will.

Cross-guide Moreno directional coupler in empty substrate integrated waveguide

NASA Astrophysics Data System (ADS)

Miralles, E.; Belenguer, A.; Esteban, H.; Boria, V.

2017-05-01

Substrate integrated waveguides (SIWs) combine the advantages of rectangular waveguides (low losses) and planar circuits (low cost and low profile). Empty substrate integrated waveguide (ESIW) has been proposed as a novel configuration in SIWs recently. This technology significantly reduces the losses of conventional SIW by removing its inner dielectric. The cross-guide directional coupler is a well-known low-profile design for having a broadband waveguide coupler. In this paper a cross-guide coupler with ESIW technique is proposed. In such a manner, the device can be integrated with microwave circuits and other printed circuit board components. It is the first time that a cross-guide coupler is implemented in ESIW technology. The designed, fabricated, and measured device presents good results as a matter of insertion loss of 1 dB (including transitions), reflection under 20 dB, coupling between 19.5 and 21.5 dB, and directivity higher than 15 dB over targeted frequency range from 12.4 GHz to 18 GHz. The coupler implemented in ESIW improves the directivity when compared to similar solutions in other empty substrate integrated waveguide solutions.

Reliability of 3-Dimensional Measures of Single-Leg Cross Drop Landing Across 3 Different Institutions

PubMed Central

DiCesare, Christopher A.; Bates, Nathaniel A.; Barber Foss, Kim D.; Thomas, Staci M.; Wordeman, Samuel C.; Sugimoto, Dai; Roewer, Benjamin D.; Medina McKeon, Jennifer M.; Di Stasi, Stephanie; Noehren, Brian W.; Ford, Kevin R.; Kiefer, Adam W.; Hewett, Timothy E.; Myer, Gregory D.

2015-01-01

Background: Anterior cruciate ligament (ACL) injuries are physically and financially devastating but affect a relatively small percentage of the population. Prospective identification of risk factors for ACL injury necessitates a large sample size; therefore, study of this injury would benefit from a multicenter approach. Purpose: To determine the reliability of kinematic and kinetic measures of a single-leg cross drop task across 3 institutions. Study Design: Controlled laboratory study. Methods: Twenty-five female high school volleyball players participated in this study. Three-dimensional motion data of each participant performing the single-leg cross drop were collected at 3 institutions over a period of 4 weeks. Coefficients of multiple correlation were calculated to assess the reliability of kinematic and kinetic measures during the landing phase of the movement. Results: Between-centers reliability for kinematic waveforms in the frontal and sagittal planes was good, but moderate in the transverse plane. Between-centers reliability for kinetic waveforms was good in the sagittal, frontal, and transverse planes. Conclusion: Based on these findings, the single-leg cross drop task has moderate to good reliability of kinematic and kinetic measures across institutions after implementation of a standardized testing protocol. Clinical Relevance: Multicenter collaborations can increase study numbers and generalize results, which is beneficial for studies of relatively rare phenomena, such as ACL injury. An important step is to determine the reliability of risk assessments across institutions before a multicenter collaboration can be initiated. PMID:26779550

Optimal Sparse Upstream Sensor Placement for Hydrokinetic Turbines

NASA Astrophysics Data System (ADS)

Cavagnaro, Robert; Strom, Benjamin; Ross, Hannah; Hill, Craig; Polagye, Brian

2016-11-01

Accurate measurement of the flow field incident upon a hydrokinetic turbine is critical for performance evaluation during testing and setting boundary conditions in simulation. Additionally, turbine controllers may leverage real-time flow measurements. Particle image velocimetry (PIV) is capable of rendering a flow field over a wide spatial domain in a controlled, laboratory environment. However, PIV's lack of suitability for natural marine environments, high cost, and intensive post-processing diminish its potential for control applications. Conversely, sensors such as acoustic Doppler velocimeters (ADVs), are designed for field deployment and real-time measurement, but over a small spatial domain. Sparsity-promoting regression analysis such as LASSO is utilized to improve the efficacy of point measurements for real-time applications by determining optimal spatial placement for a small number of ADVs using a training set of PIV velocity fields and turbine data. The study is conducted in a flume (0.8 m2 cross-sectional area, 1 m/s flow) with laboratory-scale axial and cross-flow turbines. Predicted turbine performance utilizing the optimal sparse sensor network and associated regression model is compared to actual performance with corresponding PIV measurements.

Physical Activity among Older People and Related Factors

ERIC Educational Resources Information Center

Persson, Ann; While, Alison

2012-01-01

Objective: To investigate the duration, intensity and type of physical activity undertaken by people aged 60 years and over in relation to their reported levels of participation in social activities and their perceptions of their neighbourhood. Design: A cross-sectional questionnaire survey of older people attending two luncheon and eight social…

36 CFR 7.86 - Big Cypress National Preserve.

Code of Federal Regulations, 2010 CFR

2010-07-01

... designed, modified for or capable of cross country travel on or immediately over land, water, marsh... National Park Service within the boundaries of the Preserve. (2) Travel in Preserve areas. (i) Unless... permit, and (iv) Acknowledges in the permit that he/she has no interest in the real property. (2...

Phenotyping a RIL Population for Middle-Season Drought Resistance in Cultivated Peanut

USDA-ARS?s Scientific Manuscript database

A RIL population of 150 genotypes, resulting from the cross of “Tifrunner” and “C76-16,” was examined for middle-season drought tolerance over two different growing seasons, using an augmented experimental design. Plants were grown in environmentally-controlled rainout shelters and phenotyped using...

A Cross-Cultural Journey into Literacy Research

ERIC Educational Resources Information Center

Tour, Ekaterina

2012-01-01

A significant body of literacy and language research over the last two decades has been informed by a sociocultural perspective and an associated qualitative design, which are often seen as valuable and appropriate for researching literacy. As an emergent researcher, whose understanding of language education was mostly informed by individualistic…

InternationaL cross-sectIonAl and longItudinal assessment on aSthma cONtrol in European adult patients - the LIAISON study protocol

PubMed Central

2013-01-01

Background According to international guidelines, the goal of asthma management is to achieve and maintain control of the disease, which can be assessed using composite measures. Prospective studies are required to determine how these measures are associated with asthma outcomes and/or future risk. The ‘InternationaL cross-sectIonAl and longItudinal assessment on aSthma cONtrol (LIAISON)’ observational study has been designed to evaluate asthma control and its determinants, including components of asthma management. Methods/design The LIAISON study will be conducted in 12 European countries and comprises a cross-sectional phase and a 12-month prospective phase. Both phases will aim at assessing asthma control (six-item Asthma Control Questionnaire, ACQ), asthma-related quality of life (Mini Asthma Quality of Life Questionnaire, Mini-AQLQ), risk of non-adherence to treatment (four-item Morisky Medication Adherence Scale, MMAS-4), potential reasons for poor control, treatment strategies and associated healthcare costs. The cross-sectional phase will recruit > 8,000 adult patients diagnosed with asthma for at least 6 months and receiving the same asthma treatment in the 4 weeks before enrolment. The prospective phase will include all patients with uncontrolled/poorly controlled asthma at the initial visit to assess the proportion reaching control during follow-up and to examine predictors of future risk. Visits will take place after 3, 6 and 12 months. Discussion The LIAISON study will provide important information on the prevalence of asthma control and on the quality of life in a broad spectrum of real-life patient populations from different European countries and will also contribute to evaluate differences in management strategies and their impact on healthcare costs over 12 months of observation. Trial registration ClinicalTrials.gov identifier, NCT01567280. PMID:23530817

Does Life Seem Better on a Sunny Day? Examining the Association between Daily Weather Conditions and Life Satisfaction Judgments

PubMed Central

Lucas, Richard E.; Lawless, Nicole M.

2013-01-01

Weather conditions have been shown to affect a broad range of thoughts, feelings, and behaviors. The current study examines whether these effects extend to life satisfaction judgments. We examine the association between daily weather conditions and life satisfaction in a representative sample of over 1 million Americans from all 50 states who were assessed (in a cross-sectional design) over a 5-year period. Most daily weather conditions were unrelated to life satisfaction judgments, and those effects that were significant reflect very small effects that were only detectable because of the extremely high power of these analyses. These results show that weather does not reliably affect judgments of life satisfaction. PMID:23607534

Cross-modal links among vision, audition, and touch in complex environments.

PubMed

Ferris, Thomas K; Sarter, Nadine B

2008-02-01

This study sought to determine whether performance effects of cross-modal spatial links that were observed in earlier laboratory studies scale to more complex environments and need to be considered in multimodal interface design. It also revisits the unresolved issue of cross-modal cuing asymmetries. Previous laboratory studies employing simple cues, tasks, and/or targets have demonstrated that the efficiency of processing visual, auditory, and tactile stimuli is affected by the modality, lateralization, and timing of surrounding cues. Very few studies have investigated these cross-modal constraints in the context of more complex environments to determine whether they scale and how complexity affects the nature of cross-modal cuing asymmetries. Amicroworld simulation of battlefield operations with a complex task set and meaningful visual, auditory, and tactile stimuli was used to investigate cuing effects for all cross-modal pairings. Significant asymmetric performance effects of cross-modal spatial links were observed. Auditory cues shortened response latencies for collocated visual targets but visual cues did not do the same for collocated auditory targets. Responses to contralateral (rather than ipsilateral) targets were faster for tactually cued auditory targets and each visual-tactile cue-target combination, suggesting an inhibition-of-return effect. The spatial relationships between multimodal cues and targets significantly affect target response times in complex environments. The performance effects of cross-modal links and the observed cross-modal cuing asymmetries need to be examined in more detail and considered in future interface design. The findings from this study have implications for the design of multimodal and adaptive interfaces and for supporting attention management in complex, data-rich domains.

Collaboration in recall: do pairs of people cross-cue each other to produce new memories?

PubMed

Meudell, P R; Hitch, G J; Boyle, M M

1995-02-01

When people collaborate over their recall of a shared experience, it might be expected that they could "cross-cue" each other so as to produce new memories not available to either member of the pair on their own. In a previous series of experiments (Meudell et al., 1992), we found that pairs of people always recalled more than one person, but we failed to show that social interaction facilitated performance so as to produce such "emergent" new memories. However, a phenomenon akin to cross-cuing was employed by Tulving and Pearlstone (1966) in their classic study of the availability and accessibility of memories; accordingly, in this study, we repeated Tulving and Pearlstone's work directly in a social context. So as to assess whether new memories emerged in collaborating pairs, a sequential design was employed. People learned categorized lists of words, and then all the subjects recalled the items strictly on their own. Subjects then recalled again in pairs (collaboratively) or once more on their own. The results showed that even when the opportunity for cross-cuing was directly manipulated through the provision of categorized lists, no additional new memories emerged in the collaborating groups. Possible mechanisms for the results are considered.

Microbially synthesized modular virus-like particles and capsomeres displaying group A streptococcus hypervariable antigenic determinants.

PubMed

Chuan, Yap P; Wibowo, Nani; Connors, Natalie K; Wu, Yang; Hughes, Fiona K; Batzloff, Michael R; Lua, Linda H L; Middelberg, Anton P J

2014-06-01

Effective and low-cost vaccines are essential to control severe group A streptococcus (GAS) infections prevalent in low-income nations and the Australian aboriginal communities. Highly diverse and endemic circulating GAS strains mandate broad-coverage and customized vaccines. This study describes an approach to deliver cross-reactive antigens from endemic GAS strains using modular virus-like particle (VLP) and capsomere systems. The antigens studied were three heterologous N-terminal peptides (GAS1, GAS2, and GAS3) from the GAS surface M-protein that are specific to endemic strains in Australia Northern Territory Aboriginal communities. In vivo data presented here demonstrated salient characteristics of the modular delivery systems in the context of GAS vaccine design. First, the antigenic peptides, when delivered by unadjuvanted modular VLPs or adjuvanted capsomeres, induced high titers of peptide-specific IgG antibodies (over 1 × 10(4) ). Second, delivery by capsomere was superior to VLP for one of the peptides investigated (GAS3), demonstrating that the delivery system relative effectiveness was antigen-dependant. Third, significant cross-reactivity of GAS2-induced IgG with GAS1 was observed using either VLP or capsomere, showing the possibility of broad-coverage vaccine design using these delivery systems and cross-reactive antigens. Fourth, a formulation containing three pre-mixed modular VLPs, each at a low dose of 5 μg (corresponding to <600 ng of each GAS peptide), induced significant titers of IgGs specific to each peptide, demonstrating that a multivalent, broad-coverage VLP vaccine formulation was possible. In summary, the modular VLPs and capsomeres reported here demonstrate, with promising preliminary data, innovative ways to design GAS vaccines using VLP and capsomere delivery systems amenable to microbial synthesis, potentially adoptable by developing countries. © 2013 Wiley Periodicals, Inc.

Exposure to polychlorinated biphenyls and the thyroid gland - examining and discussing possible longitudinal health effects in humans.

PubMed

Gaum, Petra M; Lang, Jessica; Esser, André; Schettgen, Thomas; Neulen, Joseph; Kraus, Thomas; Gube, Monika

2016-07-01

Many previous studies have dealt with the effect of polychlorinated biphenyls (PCBs) on the thyroid gland, but their findings are inconsistent. One problem of these studies has been their use of cross-sectional designs. The aim of the current study is to investigate longitudinal effects of PCBs on the thyroid gland, focusing on: morphological changes in thyroid tissue (i.e. thyroid volume), changes in thyroid hormones and in thyroid antibodies. A total of 122 individuals (Mage=44.7) were examined over a period of four years (t(1) until t(4)). Medical history was collected via interviews, an ultrasound examination was performed and blood samples were taken to determine plasma PCB levels, thyroid stimulating hormone (TSH), free triiodthyronine (fT3), free thyroxine (fT4), thyroid peroxidase antibodies (TPOab), thyreoglobulin antibodies (TGab) and thyroid-stimulating hormone receptor antibodies (TSHRab). Rank correlation coefficients and mixed effect models were performed controlling for age and total lipids. There were negative correlations between higher chlorinated biphenyls and fT3, cross-sectionally as well as longitudinally. We also found an interaction effect of higher-chlorinated PCBs over time for fT4 as well as TSHRab. In case of high exposure, a decrease in fT4 and an increase in TSHRab level were found over time. In regards to the other variables, our findings yielded no clear results in the examined time period. This is the first study to shows a PCB-related effect on fT3, fT4 and TSHRab over a four year period. The data also suggest that morphological and antibody findings remain inconsistent and do not allow for unambiguous interpretation. Copyright © 2016 Elsevier Inc. All rights reserved.

Determining wildlife use of wildlife crossing structures under different scenarios.

DOT National Transportation Integrated Search

2012-05-01

This research evaluated Utahs wildlife crossing structures to help UDOT and the Utah Division of Wildlife Resources assess crossing efficacy. In this study, remote motion-sensed cameras were used at 14 designated wildlife crossing culverts and bri...

The Impact of a Signalized Crosswalk on Traffic Speed and Street-Crossing Behaviors of Residents in an Underserved Neighborhood.

PubMed

Schultz, Courtney L; Sayers, Stephen P; Wilhelm Stanis, Sonja A; Thombs, Lori A; Thomas, Ian M; Canfield, Shannon M

2015-10-01

Infrastructure improvements such as pedestrian crosswalks that calm traffic and increase access to physical activity opportunities could alleviate important barriers to active living in underserved communities with outdated built environments. The purpose of this study was to explore how the built environment influences street-crossing behaviors and traffic speeds in a low-income neighborhood with barriers to active living in Columbia, Missouri. In 2013, a signalized pedestrian crosswalk and 400-ft-long median was constructed along a busy 5-lane, high-speed arterial highway linking low-income housing with a park and downtown areas. Data collection occurred prior to June 2012, and after June 2013, completion of the project at the intervention site and control site. Direct observation of street-crossing behaviors was performed at designated intersections/crosswalks or non-designated crossing points. Traffic volume and speed were captured using embedded magnetic traffic detectors. At the intervention site, designated crossings increased at the new crosswalk (p < 0.001), but not at non-designated crossings (p = 0.52) or designated crossings at intersections (p = 0.41). At the control site, there was no change in designated crossings (p = 0.94) or non-designated crossings (p = 0.79). Motor vehicles traveling above the speed limit of 35 mph decreased from 62,056 (46 %) to 46,256 (35 %) (p < 0.001) at the intervention site and increased from 57,891 (49 %) to 65,725 (59 %) (p < 0.001) at the control site. The installation of a signalized crosswalk facilitated an increase in safe street crossings and calmed traffic volume and speed in an underserved neighborhood. We believe these findings have significant public health implications that could be critical to advocacy efforts to improve infrastructure projects in similar communities.

Are Video Games a Gateway to Gambling? A Longitudinal Study Based on a Representative Norwegian Sample.

PubMed

Molde, Helge; Holmøy, Bjørn; Merkesdal, Aleksander Garvik; Torsheim, Torbjørn; Mentzoni, Rune Aune; Hanns, Daniel; Sagoe, Dominic; Pallesen, Ståle

2018-06-05

The scope and variety of video games and monetary gambling opportunities are expanding rapidly. In many ways, these forms of entertainment are converging on digital and online video games and gambling sites. However, little is known about the relationship between video gaming and gambling. The present study explored the possibility of a directional relationship between measures of problem gaming and problem gambling, while also controlling for the influence of sex and age. In contrast to most previous investigations which are based on cross-sectional designs and non-representative samples, the present study utilized a longitudinal design conducted over 2 years (2013, 2015) and comprising 4601 participants (males 47.2%, age range 16-74) drawn from a random sample from the general population. Video gaming and gambling were assessed using the Gaming Addiction Scale for Adolescents and the Canadian Problem Gambling Index, respectively. Using an autoregressive cross-lagged structural equation model, we found a positive relationship between scores on problematic gaming and later scores on problematic gambling, whereas we found no evidence of the reverse relationship. Hence, video gaming problems appear to be a gateway behavior to problematic gambling behavior. In future research, one should continue to monitor the possible reciprocal behavioral influences between gambling and video gaming.

Analysis of a Chevron Beam Thermal Actuator

NASA Astrophysics Data System (ADS)

Joshi, Amey Sanjay; Mohammed, Hussain; Kulkarni, S. M., Dr.

2018-02-01

Thermal MEMS (Micro-Electro-Mechanical Systems) actuators and sensors have a wide range of applications. The chevron type thermal actuators comparatively show superior performance over other existing electrostatic and thermal actuators. This paper describes the design and analysis of chevron type thermal actuator. Here standard design of Chevron type thermal actuator is considered which comprises of proof mass at center and array of six beams of a uniform cross section of 3 3 microns and an initial angle of 5°. The thermal actuator was designed and analyzed using analytical and finite element method and the results were compared. The model was also analyzed for initial angles of 2.5° and 7.5°, and the results were compared with FEA model. The cross section of the beam was varied and the finite element analysis of all three models was compared to suggest the best suitable thermal actuator structure.

Teaching scientific literacy in an introductory women's studies course: a case study in interdisciplinary collaboration

NASA Astrophysics Data System (ADS)

Fuselier, Linda; Murphy, Claudia; Bender, Anita; Creel Falcón, Kandace

2015-01-01

Background and purpose:The purpose of this exploratory case study is to describe how scholars negotiated disciplinary divides to develop and communicate to their students an understanding of the basic features of scientific knowledge. Our goals were to examine boundary crossing in interdisciplinary collaboration and to assess the efficacy of adding science content to an introductory Women's Studies course. Sample:We studied a collaboration between faculty in Biology and Women's Studies and evaluated science modules in a Women's Studies course at a regional four-year university in the Midwestern USA. The study included 186 student participants over three semesters and four faculty from Philosophy, Women's Studies and Biology. Design and method:Women's Studies and Biology faculty collaborated to design and implement science content learning modules that included the case of women and science in an introductory Women's Studies course. Qualitative data collected from faculty participants in the form of peer debrief sessions and narrative reflections were used to examine the process of interdisciplinary collaboration. Students exposed to curriculum changes were administered pre- and post-lesson surveys to evaluate their understanding of issues faced by women in science careers, the nature of science, and interest in science studies. Data from collaborators, student journal reflections, and pre-/post-lesson surveys were considered together in an evaluation of how knowledge of science was understood and taught in a Women's Studies course over a longitudinal study of three semesters. Results:We found evidence of discipline-based challenges to interdisciplinarity and disciplinary boundary crossing among collaborators. Three themes emerged from our collaboration: challenges posed by disciplinary differences, creation of a space for interdisciplinary work, and evidence of boundary crossing. Student participants exhibited more prior knowledge of Women's Studies content than nature of science but showed learning in the areas of scientific literacy and the understanding of issues related to women in science careers. Student understanding of science content was enhanced by the participation of a woman scientist in the learning module. Conclusion:This case study illustrates how creating an inclusive space for interdisciplinary collaboration led to successful curriculum transformation and academic boundary crossing by faculty participants. Success is evident in the legacy of interdisciplinarity in the curriculum and learning gains by students. Use of a feminist science studies framework was successful at helping students learn about the influence of values on science and the tentative nature of scientific conclusions. It was less successful in teaching the distinction between science and other ways of knowing and the conception that science is an evidence-based approach to understanding the natural world. This study highlights the importance of interdisciplinary teams of faculty members collaborating to help students learn about science by modeling that there are multiple ways of knowing.

Designing Interaction for Next Generation Personal Computing

NASA Astrophysics Data System (ADS)

de Michelis, Giorgio; Loregian, Marco; Moderini, Claudio; Marti, Patrizia; Colombo, Cesare; Bannon, Liam; Storni, Cristiano; Susani, Marco

Over two decades of research in the field of Interaction Design and Computer Supported Cooperative Work convinced us that the current design of workstations no longer fits users’ needs. It is time to design new personal computers based on metaphors alternative to the desktop one. With this SIG, we are seeking to involve international HCI professionals into the challenges of designing products that are radically new and tackling the many different issues of modern knowledge workers. We would like to engage a wider cross-section of the community: our focus will be on issues of development and participation and the impact of different values in our work.

An examination of the effectiveness of Handwriting Without Tears instruction.

PubMed

Roberts, Gwenyth I; Derkach-Ferguson, Alanna F; Siever, Jodi E; Rose, M Sarah

2014-04-01

Handwriting is an important childhood occupation, and implications of poor handwriting may have significant long-term effects. The purpose of this study was to determine the effectiveness of Handwriting Without Tears (HWT) on Grade I students' handwriting and perception of skills. A cross-over design was used. Repeated measures, at three points, included the Minnesota Handwriting Assessment (MHA) and performance rating scales. Eighty-three boys and 66 girls with an average age of 6.2 years participated in the study. Students receiving HWT achieved significantly higher improvements compared to students with teacher-designed instruction in MHA Total Test Score and in MHA components of form, size, space, and alignment (all p < .05). Students had higher average performance ratings when receiving HWT in the first half of the school year. Instruction using HWT improves students' perception and skill in handwriting performance.

Methodology Series Module 4: Clinical Trials.

PubMed

Setia, Maninder Singh

2016-01-01

In a clinical trial, study participants are (usually) divided into two groups. One group is then given the intervention and the other group is not given the intervention (or may be given some existing standard of care). We compare the outcomes in these groups and assess the role of intervention. Some of the trial designs are (1) parallel study design, (2) cross-over design, (3) factorial design, and (4) withdrawal group design. The trials can also be classified according to the stage of the trial (Phase I, II, III, and IV) or the nature of the trial (efficacy vs. effectiveness trials, superiority vs. equivalence trials). Randomization is one of the procedures by which we allocate different interventions to the groups. It ensures that all the included participants have a specified probability of being allocated to either of the groups in the intervention study. If participants and the investigator know about the allocation of the intervention, then it is called an "open trial." However, many of the trials are not open - they are blinded. Blinding is useful to minimize bias in clinical trials. The researcher should familiarize themselves with the CONSORT statement and the appropriate Clinical Trials Registry of India.

Methodology Series Module 4: Clinical Trials

PubMed Central

Setia, Maninder Singh

2016-01-01

In a clinical trial, study participants are (usually) divided into two groups. One group is then given the intervention and the other group is not given the intervention (or may be given some existing standard of care). We compare the outcomes in these groups and assess the role of intervention. Some of the trial designs are (1) parallel study design, (2) cross-over design, (3) factorial design, and (4) withdrawal group design. The trials can also be classified according to the stage of the trial (Phase I, II, III, and IV) or the nature of the trial (efficacy vs. effectiveness trials, superiority vs. equivalence trials). Randomization is one of the procedures by which we allocate different interventions to the groups. It ensures that all the included participants have a specified probability of being allocated to either of the groups in the intervention study. If participants and the investigator know about the allocation of the intervention, then it is called an “open trial.” However, many of the trials are not open – they are blinded. Blinding is useful to minimize bias in clinical trials. The researcher should familiarize themselves with the CONSORT statement and the appropriate Clinical Trials Registry of India. PMID:27512184

Pipeline corridors through wetlands -- Impacts on plant communities: Little Timber Creek Crossing, Gloucester County, New Jersey. Topical report, August 1991--January 1993

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

Shem, L.M.; Zimmerman, R.E.; Alsum, S.K.

1994-12-01

The goal of the Gas Research Institute Wetland Corridors Program is to document impacts of existing pipelines on the wetlands they traverse. To accomplish this goal, 12 existing wetland crossings were surveyed. These sites varied in elapsed time since pipeline construction, wetland type, pipeline installation techniques, and right-of-way (ROW) management practices. This report presents results of a survey conducted over the period of August 5--7, 1991, at the Little Timber Creek crossing in Gloucester County, New Jersey, where three pipelines, constructed in 1950, 1960, and 1990, cross the creek and associated wetlands. The old side of the ROW, created bymore » the installation of the 1960 pipeline, was designed to contain a raised peat bed over the 1950 pipeline and an open-water ditch over the 1960 pipeline. The new portion of the ROW, created by installation of the 1990 pipeline, has an open-water ditch over the pipeline (resulting from settling of the backfill) and a raised peat bed (resulting from rebound of compacted peat). Both the old and new ROWs contain dense stands of herbs; the vegetation on the old ROW was more similar to that in the adjacent natural area than was vegetation in the new ROW. The ROW increased species and habitat diversity in the wetlands. It may contribute to the spread of purple loosestrife and affect species sensitive to habitat fragmentation.« less

Effects of Pelvic and Core Strength Training on High School Cross-Country Race Times.

PubMed

Clark, Anne W; Goedeke, Maggie K; Cunningham, Saengchoy R; Rockwell, Derek E; Lehecka, Bryan J; Manske, Robert C; Smith, Barbara S

2017-08-01

Clark, AW, Goedeke, MK, Cunningham, SR, Rockwell, DE, Lehecka, BJ, Manske, RC, and Smith, BS. Effects of pelvic and core strength training on high school cross-country race times. J Strength Cond Res 31(8): 2289-2295, 2017-There is only limited research examining the effect of pelvic and core strength training on running performance. Pelvic and core muscle fatigue is believed to contribute to excess motion along frontal and transverse planes which decreases efficiency in normal sagittal plane running motions. The purpose of this study was to determine whether adding a 6-week pelvic and core strengthening program resulted in decreased race times in high school cross-country runners. Thirty-five high school cross-country runners (14-19 years old) from 2 high schools were randomly assigned to a strengthening group (experimental) or a nonstrengthening group (control). All participants completed 4 standardized isometric strength tests for hip abductors, adductors, extensors, and core musculature in a test-retest design. The experimental group performed a 6-week pelvic and core strengthening program along with their normal training. Participants in the control group performed their normal training without additional pelvic and core strengthening. Baseline, 3-week, and 6-week race times were collected using a repeated measures design. No significant interaction between experimental and control groups regarding decreasing race times and increasing pelvic and core musculature strength occurred over the 6-week study period. Both groups increased strength and decreased overall race times. Clinically significant findings reveal a 6-week pelvic and core stability strengthening program 3 times a week in addition to coach led team training may help decrease race times.

Determination of channel change for selected streams, Maricopa County, Arizona

USGS Publications Warehouse

Capesius, Joseph P.; Lehman, Ted W.

2002-01-01

In Maricopa County, Arizona, 10 sites on seven streams were studied to determine the lateral and vertical change of the channel. Channel change was studied over time scales ranging from individual floods to decades using cross-section surveys, discharge measurements, changes in the point of zero flow, and repeat photography. All of the channels showed some change in cross-section area or hydraulic radius over the time scales studied, but the direction and mag-nitude of change varied considerably from one flow, or series of flows, to another. The documentation of cross-section geometry for streams in Maricopa County for long-term monitoring was begun in this study.

What Can Repeated Cross-Sectional Studies Tell Us about Student Growth? Research Report. ETS RR-12-17

ERIC Educational Resources Information Center

Almond, Russell G.; Sinharay, Sandip

2012-01-01

To answer questions about how students' proficiencies are changing over time, educational researchers are looking for data sources that span many years. Clearly, for answering questions about student growth, a longitudinal study--in which a single sample is followed over many years--is preferable to repeated cross-sectional samples--in which a…

Polarization Properties of A Broadband Multi-Moded Concentrator

NASA Technical Reports Server (NTRS)

Kogut, Alan; Fixsen, Dale J.; Hill, Robert S.

2015-01-01

We present the design and performance of a non-imaging concentrator for use in broad-band polarimetry at millimeter through submillimeter wavelengths. A rectangular geometry preserves the input polarization state as the concentrator couples f/2 incident optics to a 2pi sr detector. Measurements of the co-polar and cross-polar beams in both the few-mode and highly over-moded limits agree with a simple model based on mode truncation. The measured co-polar beam pattern is nearly independent of frequency in both linear polarizations. The cross-polar beam pattern is dominated by a uniform term corresponding to polarization efficiency 94%. After correcting for efficiency, the remaining cross-polar response is -18 dB.

Behavior Treatment of Deviant Sex-Role Behaviors in a Male Child.

ERIC Educational Resources Information Center

Rekers, George A.; And Others

This study demonstrated reinforcement control over pronounced feminine behaviors in a male child who had been psychologically evaluated as manifesting "childhood cross-gender identity." Reinforcement control over cross-gender behavior was demonstrated by identifying some behavioral treatment conditions under which feminine behaviors could be…

Road crossing designs and their impact on fish assemblages of Great Plains streams

USGS Publications Warehouse

Bouska, Wesley W.; Paukert, Craig P.

2010-01-01

A mark-recapture field study was conducted to determine fish passage at 5 concrete box culverts and 5 low-water crossings (concrete slabs vented by culverts) as well as 10 control sites (below a natural riffle) in Flint Hills streams of northeastern Kansas. Additionally, we tested the upstream passage of four fish species native to Great Plains streams (Topeka shiner Notropis topeka, green sunfish Lepomis cyanellus, red shiner Cyprinella lutrensis, and southern redbelly dace Phoxinus erythrogaster) through three simulated crossing designs (box culverts, round corrugated culverts, and natural rock riffles) at water velocities of 0.1 to 1.1 m/s in an experimental stream. The field study indicated that cyprinids were twice as likely to move upstream of box culverts than low-water crossings and 1.4 times as likely to move upstream of control reaches than any crossing type. The best models indicated that the proportion of cyprinids that moved upstream increased with decreased culvert slope and length, perching, and increased culvert width. Our controlled experiment indicated that fish can move through velocities up to 1.1 m/s in a 1.86-m simulated stream and that the proportion of fish that moved upstream did not differ among crossing designs for southern redbelly dace, green sunfish, or Topeka shiner; however, natural rock riffles had lower proportional movements (mean = 0.19) than the box (0.38) or corrugated culvert designs (0.43) for red shiners. Water velocity did not affect the proportional upstream movement of any species except that of Topeka shiners, which increased with water velocity. Crossing design alone may not determine fish passage, and water velocities up to 1.1 m/s may not affect the passage of many Great Plains fishes. Barriers to fish movement may be the result of other factors (e.g., perching, slope, and crossing length). The use of properly designed and installed crossings has promise in conserving Great Plains stream fishes.

A cross-validation package driving Netica with python

USGS Publications Warehouse

Fienen, Michael N.; Plant, Nathaniel G.

2014-01-01

Bayesian networks (BNs) are powerful tools for probabilistically simulating natural systems and emulating process models. Cross validation is a technique to avoid overfitting resulting from overly complex BNs. Overfitting reduces predictive skill. Cross-validation for BNs is known but rarely implemented due partly to a lack of software tools designed to work with available BN packages. CVNetica is open-source, written in Python, and extends the Netica software package to perform cross-validation and read, rebuild, and learn BNs from data. Insights gained from cross-validation and implications on prediction versus description are illustrated with: a data-driven oceanographic application; and a model-emulation application. These examples show that overfitting occurs when BNs become more complex than allowed by supporting data and overfitting incurs computational costs as well as causing a reduction in prediction skill. CVNetica evaluates overfitting using several complexity metrics (we used level of discretization) and its impact on performance metrics (we used skill).

On the role of passion for work in burnout: a process model.

PubMed

Vallerand, Robert J; Paquet, Yvan; Philippe, Frederick L; Charest, Julie

2010-02-01

The purpose of the present research was to test a model on the role of passion for work in professional burnout. This model posits that obsessive passion produces conflict between work and other life activities because the person cannot let go of the work activity. Conversely, harmonious passion is expected to prevent conflict while positively contributing to work satisfaction. Finally, conflict is expected to contribute to burnout, whereas work satisfaction should prevent its occurrence. This model was tested in 2 studies with nurses in 2 cultures. Using a cross-sectional design, Study 1 (n=97) provided support for the model with nurses from France. In Study 2 (n=258), a prospective design was used to further test the model with nurses from the Province of Quebec over a 6-month period. Results provided support for the model. Specifically, harmonious passion predicted an increase in work satisfaction and a decrease in conflict. Conversely, obsessive passion predicted an increase of conflict. In turn, work satisfaction and conflict predicted decreases and increases in burnout changes that took place over time. The results have important implications for theory and research on passion as well as burnout.

New cochlear implant research coding strategy based on the MP3(000™) strategy to reintroduce the virtual channel effect.

PubMed

Neben, Nicole; Lenarz, Thomas; Schuessler, Mark; Harpel, Theo; Buechner, Andreas

2013-05-01

Results for speech recognition in noise tests when using a new research coding strategy designed to introduce the virtual channel effect provided no advantage over MP3(000™). Although statistically significant smaller just noticeable differences (JNDs) were obtained, the findings for pitch ranking proved to have little clinical impact. The aim of this study was to explore whether modifications to MP3000 by including sequential virtual channel stimulation would lead to further improvements in hearing, particularly for speech recognition in background noise and in competing-talker conditions, and to compare results for pitch perception and melody recognition, as well as informally collect subjective impressions on strategy preference. Nine experienced cochlear implant subjects were recruited for the prospective study. Two variants of the experimental strategy were compared to MP3000. The study design was a single-blinded ABCCBA cross-over trial paradigm with 3 weeks of take-home experience for each user condition. Comparing results of pitch-ranking, a significantly reduced JND was identified. No significant effect of coding strategy on speech understanding in noise or competing-talker materials was found. Melody recognition skills were the same under all user conditions.

Estimation of available global solar radiation using sunshine duration over South Korea

NASA Astrophysics Data System (ADS)

Das, Amrita; Park, Jin-ki; Park, Jong-hwa

2015-11-01

Besides designing a solar energy system, accurate insolation data is also a key component for many biological and atmospheric studies. But solar radiation stations are not widely available due to financial and technical limitations; this insufficient number affects the spatial resolution whenever an attempt is made to construct a solar radiation map. There are several models in literature for estimating incoming solar radiation using sunshine fraction. Seventeen of such models among which 6 are linear and 11 non-linear, have been chosen for studying and estimating solar radiation on a horizontal surface over South Korea. The better performance of a non-linear model signifies the fact that the relationship between sunshine duration and clearness index does not follow a straight line. With such a model solar radiation over 79 stations measuring sunshine duration is computed and used as input for spatial interpolation. Finally monthly solar radiation maps are constructed using the Ordinary Kriging method. The cross validation results show good agreement between observed and predicted data.

Preliminary Weight Savings Estimate for a Commercial Transport Wing Using Rod-Stiffened Stitched Composite Technology

NASA Technical Reports Server (NTRS)

Lovejoy, Andrew E.

2015-01-01

A structural concept called pultruded rod stitched efficient unitized structure (PRSEUS) was developed by the Boeing Company to address the complex structural design aspects associated with a pressurized hybrid wing body (HWB) aircraft configuration. While PRSEUS was an enabling technology for the pressurized HWB structure, limited investigation of PRSEUS for other aircraft structures, such as circular fuselages and wings, has been done. Therefore, a study was undertaken to investigate the potential weight savings afforded by using the PRSEUS concept for a commercial transport wing. The study applied PRSEUS to the Advanced Subsonic Technology (AST) Program composite semi-span test article, which was sized using three load cases. The initial PRSEUS design was developed by matching cross-sectional stiffnesses for each stringer/skin combination within the wing covers, then the design was modified to ensure that the PRSEUS design satisfied the design criteria. It was found that the PRSEUS wing design exhibited weight savings over the blade-stiffened composite AST Program wing of nearly 9%, and a weight savings of 49% and 29% for the lower and upper covers, respectively, compared to an equivalent metallic wing.

A Cross-Sectional Analysis of Publication Types in Quality Improvement Journals.

PubMed

Wong, Christopher J; White, Andrew A; Merel, Susan E; Brock, Douglas M; Staiger, Thomas O

2016-07-01

Despite widespread engagement in quality improvement activities, little is known about the designs of studies currently published in quality improvement journals. This study's goal is to establish the prevalence of the types of research conducted in articles published in journals dedicated to quality improvement. A cross-sectional analysis was performed of 145 research articles published in 11 quality improvement journals in 2011. The majority of study designs were considered pre-experimental (95%), with a small percentage of quasi-experimental and experimental designs. Of the studies that reported the results of an intervention (n = 60), the most common research designs were pre-post studies (33%) and case studies (25%). There were few randomized controlled trials or quasi-experimental study designs (12% of intervention studies). These results suggest that there are opportunities for increased use of quasi-experimental study designs. © The Author(s) 2015.

Development and application of a newly designed massage instrument for deep cross-friction massage in chronic non-specific low back pain.

PubMed

Yoon, Yong-Soon; Yu, Ki-Pi; Lee, Kwang Jae; Kwak, Soo-Hyun; Kim, Jong Yun

2012-02-01

To introduce a newly designed massage instrument, the Hand Grip T-bar (HT-bar) and use it to relieve chronic non-specific low back pain (nLBP) through deep cross-friction massage (roptrotherapy). 22 subjects (9 males and 13 females, aged 51.6±6.7) with chronic nLBP were allocated randomly to a Roptrotherapy group (n=12) and a Transcutaneous Electrical Nerve Stimulation (TENS) group (n=10). The Roptrotherapy group received deep cross-friction massage with the HT-bar, which was made of metal and had a cylinder for increasing weight and grooves for an easy grip. It was applied across the middle and lower back for 20 minutes a day, 3 days a week for 2 weeks. The TENS group received TENS for 20 minutes a day, 5 days a week for 2 weeks. The outcome was measured on the pain numeric rating scale (PNRS), by the Oswestry disability index (ODI), and by the Roland & Morris Disability Questionnaire (RMDQ) at pre-treatment, at immediate post-treatment and 2 weeks later. The application of the HT-bar was assessed by a questionnaire to 19 therapists. At post-treatment, immediately and 2 weeks later, both groups showed significant improvement in PNRS, ODI and RMDQ. During the two weeks after post-treatment, however, the Roptrotherapy group improved in PNRS, ODI and RMDQ, but the TENS group did not. Over 80% of the therapists responded that the HT-bar was useful and comfortable. This study suggests that deep cross-friction massage can be a beneficial therapeutic technique and that the HT-bar can be a useful instrument in deep cross-friction massage for chronic nLBP patients.

Electronically cloaked nanoparticles

NASA Astrophysics Data System (ADS)

Shen, Wenqing

The concept of electronic cloaking is to design objects invisible to conduction electrons. The approach of electronic cloaking has been recently suggested to design invisible nanoparticle dopants with electronic scattering cross section smaller than 1% of the physical cross section (pi a2), and therefore to enhance the carrier mobility of bulk materials. The proposed nanoparticles have core-shell structures. The dopants are incorporated inside the core, while the shell layer serves both as a spacer to separate the charge carriers from their parent atoms and as a cloaking shell to minimize the scattering cross section of the electrons from the ionized nanoparticles. Thermoelectric materials are usually highly doped to have enough carrier density. Using invisible dopants could achieve larger thermoelectric power factors by enhancing the electronic mobility. Core-shell nanoparticles show an advantage over one-layer nanoparticles, which are proposed in three-dimensional modulation doping. However designing such nanoparticles is not easy as there are too many parameters to be considered. This thesis first shows an approach to design hollow nanoparticles by applying constrains on variables. In the second part, a simple mapping approach is introduced where one can identify possible core-shell particles by comparing the dimensionless parameters of chosen materials with provided maps. In both parts of this work, several designs with realistic materials were made and proven to achieve electronic cloaking. Improvement in the thermoelectric power factor compared to the traditional impurity doping method was demonstrated in several cases.

Advanced Clothing Studies

NASA Technical Reports Server (NTRS)

Orndoff, Evelyne; Poritz, Darwin

2014-01-01

All human space missions require significant logistical mass and volume that add an unprecedented burden on longduration missions beyond low-Earth orbit. For these missions with limited cleaning resources, a new wardrobe must be developed to reduce this logistical burden by reducing clothing mass and extending clothing wear. The present studies have been undertaken, for the first time, to measure length of wear and to assess the acceptance of such extended wear. Garments in these studies are commercially available exercise T-shirts and shorts, routine-wear T-shirts, and longsleeved pullover shirts. Fabric composition (cotton, polyester, light-weight, superfine Merino wool, modacrylic, cotton/rayon, polyester/Cocona, modacrylic/Xstatic, modacrylic/rayon, modacrylic/lyocell/aramid), construction (open knit, tight knit, open weave, tight weave), and finishing treatment (none, quaternary ammonium salt) are the independent variables. Eleven studies are reported here: five studies of exercise T-shirts, three of exercise shorts, two of routine wear Tshirts, and one of shirts used as sleep-wear. All studies are conducted in a climate-controlled environment, similar to a space vehicle's. For exercise clothing, study participants wear the garments during aerobic exercise. For routine wear clothing, study participants wear the T-shirts daily in an office or laboratory. Daily questionnaires collected data on ordinal preferences of nine sensory elements and on reason for retiring a used garment. Study 1 compares knitted cotton, polyester, and Merino exercise T-shirts (61 participants), study 2, knitted polyester, modacrylic, and polyester/Cocona exercise T-shirts (40 participants), study 3, cotton and polyester exercise shorts, knitted and woven (70 participants), all three using factorial experimental designs with and without a finishing treatment, conducted at the Johnson Space Center, sharing study participants. Study 4 compares knitted polyester and ZQ Merino exercise T-shirts, study 5, knitted ZQ Merino and modacrylic routine-wear T-shirts, with study 6 using only knitted polyester exercise shorts. No finishing treatment is used. Studies 4 and 5 use cross-over experimental designs, and all three studies were conducted aboard the ISS with six crew. Studies 4 and 6 were repeated on the ground with the same participants to learn if perception was affected microgravity. Study 7 is a longer-term, single-blind panel study of knitted routine-wear undershirts with at least 12 participants to assess tolerance to Merino by comparing it with a cotton/rayon blends, using a cross-over design, eliminating carryover effects with wash-out periods between shirts.

A Randomised Cross-Over Pharmacokinetic Bioavailability Study of Synthetic versus Kiwifruit-Derived Vitamin C

PubMed Central

Carr, Anitra C.; Bozonet, Stephanie M.; Vissers, Margreet C. M.

2013-01-01

Kiwifruit are a rich source of vitamin C and also contain numerous phytochemicals, such as flavonoids, which may influence the bioavailability of kiwifruit-derived vitamin C. The aim of this study was to compare the relative bioavailability of synthetic versus kiwifruit-derived vitamin C using a randomised cross-over pharmacokinetic study design. Nine non-smoking males (aged 18–35 years) received either a chewable tablet (200 mg vitamin C) or the equivalent dose from gold kiwifruit (Actinidia chinensis var. Sungold). Fasting blood and urine were collected half hourly to hourly over the eight hours following intervention. The ascorbate content of the plasma and urine was determined using HPLC with electrochemical detection. Plasma ascorbate levels increased from 0.5 h after the intervention (P = 0.008). No significant differences in the plasma time-concentration curves were observed between the two interventions (P = 0.645). An estimate of the total increase in plasma ascorbate indicated complete uptake of the ingested vitamin C tablet and kiwifruit-derived vitamin C. There was an increase in urinary ascorbate excretion, relative to urinary creatinine, from two hours post intervention (P < 0.001). There was also a significant difference between the two interventions, with enhanced ascorbate excretion observed in the kiwifruit group (P = 0.016). Urinary excretion was calculated as ~40% and ~50% of the ingested dose from the vitamin C tablet and kiwifruit arms, respectively. Overall, our pharmacokinetic study has shown comparable relative bioavailability of kiwifruit-derived vitamin C and synthetic vitamin C. PMID:24284610

Do obesity and weight loss affect vocal function?

PubMed

Solomon, Nancy Pearl; Helou, Leah B; Dietrich-Burns, Katie; Stojadinovic, Alexander

2011-02-01

Obesity may be associated with increased tissue bulk in the laryngeal airway, neck, and chest wall, and as such may affect vocal function. Eight obese and eight nonobese adults participated in this study; the obese participants underwent bariatric surgical procedures. This mixed-design study included cross-sectional analysis for group differences and longitudinal analysis for multidimensional changes in vocal function from four assessments collected over 6 months. No significant differences were detected between groups from the preoperative assessment. Further, no changes were detected over time for acoustic parameters, maximum phonation time, laryngeal airway resistance, and airflow during a sustained vowel for either group. Only minor differences were detected for strain, pitch, and loudness perceptions of voice over time, but not between groups. Phonation threshold pressure (PTP), at comfortable and high pitches (30% and 80% of the F0 range) changed significantly over time, but not between groups. Examination of individual data revealed a trend for PTP at 30% F0 to decrease as body mass index decreased. PTP may be informative for assessing vocal function in clients who present with obesity and voice symptoms. © Thieme Medical Publishers.

Radiation characteristics and polarisation of undulated microstrip line antennas

NASA Astrophysics Data System (ADS)

Shafai, L.; Sebak, A. A.

1985-12-01

A numerical method is used to investigate the radiation from undulated microstrip line antennas. The undulated line is assumed to be suspended over a ground plane and its current distribution is determined using a moment method type solution. This current distribution is then used to compute the co-polar and cross-polar radiation fields. It is found that the current distribution has an oscillating behavior along the line, with a frequency which is twice the number of undulations. The cross-polarization is found to be high and relatively independent of the undulating shape. Its relative level, however, is reduced for large arrays, due to the array factor affecting the co-polar field. A procedure for the reduction or elimination of the cross-polarization is then proposed, which is based on utilizing two undulated lines with mutually inverted undulations. A design method for achieving low sidelobe levels is also proposed and a design example with sidelobes around the -40 dB range is presented.

Polyphenols from cocoa and vascular health-a critical review.

PubMed

Rimbach, Gerald; Melchin, Mona; Moehring, Jennifer; Wagner, Anika E

2009-11-20

Cocoa is a rich source of dietary polyphenols. In vitro as well as cell culture data indicate that cocoa polyphenols may exhibit antioxidant and anti-inflammatory, as well as anti-atherogenic activity. Several molecular targets (e.g., nuclear factor kappa B, endothelial nitric oxide synthase, angiotensin converting enzyme) have been recently identified which may partly explain potential beneficial cardiovascular effects of cocoa polyphenols. However cocoa polyphenol concentrations, as used in many cell culture studies, are not physiologically achievable. Bioavailability studies indicate that plasma concentrations of cocoa polyphenols following dietary intake are low and in the nanomolar range. Human studies regarding the effect of cocoa polyphenols on vascular health are often underpowered and lack a rigorous study design. If dietary cocoa polyphenol intake is due to chocolate its high energy content needs to be taken into account. In order to determine potential health benefits of cocoa polyphenols large scale, long term, randomized, placebo controlled studies, (ideally with a cross-over design) as well as prospective studies are warranted.

Polyphenols from Cocoa and Vascular Health—A Critical Review

PubMed Central

Rimbach, Gerald; Melchin, Mona; Moehring, Jennifer; Wagner, Anika E.

2009-01-01

Cocoa is a rich source of dietary polyphenols. In vitro as well as cell culture data indicate that cocoa polyphenols may exhibit antioxidant and anti-inflammatory, as well as anti-atherogenic activity. Several molecular targets (e.g., nuclear factor kappa B, endothelial nitric oxide synthase, angiotensin converting enzyme) have been recently identified which may partly explain potential beneficial cardiovascular effects of cocoa polyphenols. However cocoa polyphenol concentrations, as used in many cell culture studies, are not physiologically achievable. Bioavailability studies indicate that plasma concentrations of cocoa polyphenols following dietary intake are low and in the nanomolar range. Human studies regarding the effect of cocoa polyphenols on vascular health are often underpowered and lack a rigorous study design. If dietary cocoa polyphenol intake is due to chocolate its high energy content needs to be taken into account. In order to determine potential health benefits of cocoa polyphenols large scale, long term, randomized, placebo controlled studies, (ideally with a cross-over design) as well as prospective studies are warranted. PMID:20057946

Study of different cross-shaped microchannels affecting thermal-bubble-actuated microparticle manipulation

NASA Astrophysics Data System (ADS)

Li, Weichen; Tsou, Chingfu

2015-10-01

This paper presents a thermal-bubble-actuated microfluidic chip with cross-shaped microchannels for evaluating the effect of different microchannel designs on microparticle manipulation. Four cross-shaped microchannel designs, with orthogonal, misaligned, skewed, and antiskewed types, were proposed in this study. The thermal bubble micropump, which is based on a resistive bulk microheater, was used to drive fluid transportation, and it can be realized using a simple microfabrication process with a silicon-on-isolator wafer. Using commercial COMSOL software, the flow profiles of microfluidics in various cross-shaped microchannels were simulated qualitatively under different pumping pressures. Microbeads, with a diameter of 20 μm, manipulated in four cross-shaped microchannels, were also implemented in this experiment. The results showed that a skewed microchannel design has a higher sorting rate compared with orthogonal, misaligned, and antiskewed microchannels because its flow velocity in the main microchannel is significantly reduced by pumping pressure. Typically, the successful sorting rate for this type of skewed microchannel can reach 30% at a pumping frequency of 100 Hz.

Safety effectiveness of pedestrian crossing enhancements : final report.

DOT National Transportation Integrated Search

2017-02-01

Over the last decade, the Oregon DOT and other agencies have systematically implemented many pedestrian crossing enhancements (PCEs) across the state. This study explored the safety performance of these enhanced crossing in Oregon. Detailed data were...

Genetic Expression in Cystic Fibrosis Related Bone Disease. An Observational, Transversal, Cross-Sectional Study.

PubMed

Ciuca, Ioana M; Pop, Liviu L; Rogobete, Alexandru F; Onet, Dan I; Guta-Almajan, Bogdan; Popa, Zoran; Horhat, Florin G

2016-09-01

Cystic fibrosis (CF) is the most frequent monogenic genetic disease with autosomal recessive transmission and characterized by important clinical polymorphism and significant lethal prospective. CF related bone disease occurs frequently in adults with CF. Childhood is the period of bone formation, and therefore, children are more susceptible to low bone density. Several factors like pancreatic insufficiency, hormone imbalance, and physical inactivity contribute to CF bone disease development. Revealing this would be important for prophylactic treatment against bone disease occurrence. The study was observational, transversal, with a cross-sectional design. The study included 68 children with cystic fibrosis, genotyped and monitored in the National CF Centre. At the annual assessment, besides clinical examination, biochemical evaluation for pancreatic insufficiency, and diabetes, they were evaluated for bone mineral density using dual energy X-ray absorptiometry (DXA). Twenty-six patients, aged over 10 years were diagnosed with CF bone disease, without significant gender gap. Bone disease was frequent in patients aged over 10 years with exocrine pancreatic insufficiency, carriers of severe mutations, and CF liver disease. CF carriers of a severe genotype which associates pancreatic insufficiency and CF liver disease, are more likely predisposed to low bone mineral density. Further studies should discover other significant influences in order to prevent the development of CF bone disease and an improved quality of life in cystic fibrosis children.

Challenges and opportunities for growing blackberries in areas with adverse environmental conditions

USDA-ARS?s Scientific Manuscript database

The rotating cross-arm (RCA) technology (Fig. 1) combines a unique trellis design and cane training protocol. Developed over the last two decades, this technology is beginning to have an impact on the blackberry (Genus Rubus, subgenus Rubus) industry in the United States of America (USA). It has b...

Regeneration of Russian wildrye foundation seed and its effect on genetic diversity and linkage disequilibrium

USDA-ARS?s Scientific Manuscript database

Maintaining the genetic integrity and performance of released cultivars over multiple generations of seed increase continues to be of concern in cross-pollinating grasses. It is not an uncommon practice when seed supplies are low or foundation seed is not available to designate registered seed as f...

Estimation of Complex Generalized Linear Mixed Models for Measurement and Growth

ERIC Educational Resources Information Center

Jeon, Minjeong

2012-01-01

Maximum likelihood (ML) estimation of generalized linear mixed models (GLMMs) is technically challenging because of the intractable likelihoods that involve high dimensional integrations over random effects. The problem is magnified when the random effects have a crossed design and thus the data cannot be reduced to small independent clusters. A…

The Impact of Oxytocin on Food Intake and Emotion Recognition in Patients with Eating Disorders: A Double Blind Single Dose Within-Subject Cross-Over Design.

PubMed

Kim, Youl-Ri; Eom, Jin-Sup; Yang, Jae-Won; Kang, Jiwon; Treasure, Janet

2015-01-01

Social difficulties and problems related to eating behaviour are common features of both anorexia nervosa (AN) and bulimia nervosa (BN). The aim of this study was to examine the impact of intranasal oxytocin on consummatory behaviour and emotional recognition in patients with AN and BN in comparison to healthy controls. A total of 102 women, including 35 patients with anorexia nervosa (AN), 34 patients with bulimia nervosa (BN), and 33 healthy university students of comparable age and intelligence, participated in a double-blind, single dose placebo-controlled cross-over study. A single dose of intranasal administration of oxytocin (40 IU) (or a placebo) was followed by an emotional recognition task and an apple juice drink. Food intake was then recorded for 24 hours post-test. Oxytocin produced no significant change in appetite in the acute or 24 hours free living settings in healthy controls, whereas there was a decrease in calorie consumption over 24 hours in patients with BN. Oxytocin produced a small increase in emotion recognition sensitivity in healthy controls and in patients with BN, In patients with AN, oxytocin had no effect on emotion recognition sensitivity or on consummatory behaviour. The impact of oxytocin on appetite and social cognition varied between people with AN and BN. A single dose of intranasal oxytocin decreased caloric intake over 24 hours in people with BN. People with BN showed enhanced emotional sensitivity under oxytocin condition similar to healthy controls. Those effects of oxytocin were not found in patients with AN. ClinicalTrials.gov KCT00000716.

'Petite' mutagenesis and mitotic crossing-over in yeast by DNA-targeted alkylating agents.

PubMed

Ferguson, L R; Turner, P M; Gourdie, T A; Valu, K K; Denny, W A

1989-12-01

Although the biological properties (cytotoxicity, mutagenicity and carcinogenicity) of alkylating agents result from their bonding interactions with DNA, such compounds generally do not show any special binding affinity for DNA. A series of acridine-linked aniline mustards of widely-varying alkylator reactivity have been designed as DNA-directed alkylating agents. We have considered whether such DNA targeting has an effect on mutagenic properties by evaluating this series of drugs in comparison with their untargeted counterparts for toxic, recombinogenic and mutagenic properties in Saccharomyces cerevisiae strain D5. The simple untargeted aniline mustards are effective inducers of mitotic crossing-over in this strain, but resemble other reported alkylators in being rather inefficient inducers of the "petite" or mitochondrial mutation in yeast. However, the majority of the DNA-targeted mustards were very efficient petite mutagens, while showing little evidence of mitotic crossing-over or other nuclear events. The 100% conversion of cells into petites and the lack of a differential between growing and non-growing cells are similar to the effects of the well characterised mitochondrial mutagen ethidium bromide. These data suggest very different modes of action between the DNA-targeted alkylators and their non-targeted counterparts.

Investigation of novel fractal shape of the nano-aperture as a metasurface for bio sensing application

NASA Astrophysics Data System (ADS)

Heydari, Samaneh; Rastan, Iman; Parvin, Amin; Pirooj, Azadeh; Zarrabi, Ferdows B.

2017-01-01

Recently, nano-aperture is noticed due to its good transmission in the optical regime. Also, the nano-apertures are developed at the metasurface design for circular polarization; for this aim, various shapes of the nano-aperture are suggested. To reach this objective, we have developed a novel Jerusalem cross fractal shape for a mid-infrared application. We have simulated various formations of the nano-fractal Jerusalem cross based on a simple cross to show the effect of nano-aperture shape on electrical field enhancement in the near-field which is important in spectroscopy and optical imaging. In addition, we have used a single layer graphene over the aperture as a coat for making reconfigurable characteristic also creating a membrane for placement of nano-particle over the aperture. Implementation of the graphene is an amendment to the transfer of the nano-apertures. The biological materials with a thickness of 80 nm have been placed over the graphene layer and the Figures of Merits (FOM) have been obtained. Additionally, the prototype of nano-antenna is independent from incident wave polarization. The Finite Difference Time Domain (FDTD) calculations have been implemented in the simulation and modeling the nano-apertures.

Rating Apathy in Huntington’s Disease: Patients and Companions Agree.

PubMed

Mason, Sarah; Barker, Roger A

2015-01-01

Apathy is a common feature of Huntington’s disease (HD), even from early disease. However, patients are believed to lack insight into their own apathy and therefore clinicians and/or companions are relied upon to estimate the extent of a patient’s apathy. In addition, the evolution of apathy over time in HD has not been unequivocally established. OBJECTIVEs: The purpose of this study was to determine whether HD patient’s self-rated apathy scores were consistent with the scores given by companions who were also asked to rate the patients apathy. Furthermore, the clinical correlates of apathy and its stability over time were examined for both self-rated and companion-rated scores. METHODs: Apathy was measured in a large cross-sectional population of HD patients ranging from early to late stage disease (n = 106) using the Apathy Evaluation Scale; a subgroup of whom were followed longitudinally (n = 62) on average 18.7 (1.2 SD) months later. Comparisons were made between self-rated and companion-rated apathy and the relationship between apathy and motor, cognitive and functional performance was explored. Analysis of the cross-sectional data revealed that self-rated and companion-rated apathy were highly correlated, establishing the validity of using self-rated instead of, or in combination with, companion-rated assessments of apathy in future studies. Both self-rated and companion-rated scores had a relationship with motor and functional impairment, but had a complex relationship with cognition. The results of the longitudinal comparison revealed that apathy did not change over time in this cohort.CONCLUSIONs: Apathy can be equally well assessed by either patients or companions and does not change significantly over an18 month period. These findings have implications in the design of studies looking at treating this important aspect of HD.

A Comparison of the Results of Many-Facet Rasch Analyses Based on Crossed and Judge Pair Designs

ERIC Educational Resources Information Center

Ilhan, Mustafa

2016-01-01

The aim of this study was to compare the results of many-facet Rasch analyses based on crossed and judge pair designs. The study was conducted with 168 eighth grade students and five judges. The study data were collected using an achievement test with open-ended questions and a holistic rubric that was used to rate the responses. In the data…

A comparison between over-the-head and lateral cardiopulmonary resuscitation with a single rescuer by bag-valve mask

PubMed Central

Nasiri, Ebrahim; Nasiri, Reza

2014-01-01

Context: mask fixation in the lateral position is difficult during CPR. Aim: the aim of this study is to compare the lateral CPR for the use of bag-valve mask by single paramedic rescuer as well as over-the-head CPR on the chest compression and ventilation on the manikin. Settings and Design: Mazandaran University of Medical Sciences. The design of this study was a randomized cross-over trial. Methods: participants learned a standardized theoretical introduction CPR according to the 2010 guidelines. The total number of chest compressions per two minutes was measured. Total number of correct and wrong ventilation per two minutes was evaluated. Statistical Analysis: we used Wilcoxon signed-rank test to analyze the non-normally distributed data in dependence groups A. P-value of more than 0.05 was considered to show statistical significance. Results: there were 100 participants (45 women and 55 men) who participated in the study from September to March, 2011. The compression and ventilation rate in lateral CPR was lower than OTH CPR. Around 51% of participants had correct chest compression rate more than 90 beats per minute in lateral CPR and 65% of them had equal or more than ten correct ventilations per minute. Conclusions: in conclusion, this study confirmed that in a simulated CPR model over-the-head position CPR led to a better BLS than the lateral position CPR by a single paramedic student with a BVM device. We also concluded that by this new BVM fixation method on the face of the patients in the lateral position CPR can be a good alternative over-the-head mask fixation by a single trained rescuer. PMID:24665237

S-band omnidirectional antenna for the SERT-C satellite

NASA Technical Reports Server (NTRS)

Bassett, H. L.; Cofer, J. W., Jr.; Sheppard, R. R.; Sinclair, M. J.

1975-01-01

The program to design an S-band omnidirectional antenna system for the SERT-C spacecraft is discussed. The program involved the tasks of antenna analyses by computer techniques, scale model radiation pattern measurements of a number of antenna systems, full-scale RF measurements, and the recommended design, including detailed drawings. A number of antenna elements were considered: the cavity-backed spiral, quadrifilar helix, and crossed-dipoles were chosen for in-depth studies. The final design consisted of a two-element array of cavity-backed spirals mounted on opposite sides of spacecraft and fed in-phase through a hybrid junction. This antenna system meets the coverage requirement of having a gain of at least minus 10 dBi over 50 percent of a 4 pi steradian sphere with the solar panels in operation. This coverage level is increased if the ground station has the capability to change polarization.

The Misconception of Case-Control Studies in the Plastic Surgery Literature: A Literature Audit.

PubMed

Hatchell, Alexandra C; Farrokhyar, Forough; Choi, Matthew

2017-06-01

Case-control study designs are commonly used. However, many published case-control studies are not true case-controls and are in fact mislabeled. The purpose of this study was to identify all case-control studies published in the top three plastic surgery journals over the past 10 years, assess which were truly case-control studies, clarify the actual design of the articles, and address common misconceptions. MEDLINE, Embase, and Web of Science databases were searched for case-control studies in the three highest-impact factor plastic surgery journals (2005 to 2015). Two independent reviewers screened the resulting titles, abstracts, and methods, if applicable, to identify articles labeled as case-control studies. These articles were appraised and classified as true case-control studies or non-case-control studies. The authors found 28 articles labeled as case-control studies. However, only six of these articles (21 percent) were truly case-control designs. Of the 22 incorrectly labeled studies, one (5 percent) was a randomized controlled trial, three (14 percent) were nonrandomized trials, two (9 percent) were prospective comparative cohort designs, 14 (64 percent) were retrospective comparative cohort designs, and two (9 percent) were cross-sectional designs. The mislabeling was worse in recent years, despite increases in evidence-based medicine awareness. The majority of published case-control studies are not in fact case-control studies. This misunderstanding is worsening with time. Most of these studies are actually comparative cohort designs. However, some studies are truly clinical trials and thus a higher level of evidence than originally proposed.

Effect of cross sectional geometry on PDMS micro peristaltic pump performance: comparison of SU-8 replica molding vs. micro injection molding.

PubMed

Graf, Neil J; Bowser, Michael T

2013-10-07

Two different fabrication methods were employed to fabricate micropumps with different cross-sectional channel geometries. The first was to fabricate rectangular cross-sectional microchannel geometries using the well known fabrication method of replica molding (REM). The second, and far less utilized fabrication technique, was to create microchannel molds using an in-house fabricated handheld micro injection molding apparatus. The injection mold apparatus was designed for use with elastomeric room temperature vulcanization (RTV) polymers, as opposed to most other injection molding machines, which are designed for use with thermoplastic polymers. The injection mold's bottom plate was used as a microchannel molding template. The molding template was created by threading a small-diameter wire (150 μm or less) through the injection mold's bottom plate, with subsequent adhesion and smoothing of a thin piece of aluminum foil over the wire-raised injection mold template. When molded against, the template produced a rounded/Gaussian-shaped PDMS microchannel. The design of the injection mold will be presented, along with a direct comparison for micropump performance metrics such as flow rate, valving characteristics, and maximum backpressures attainable for each of the respective micropump channel geometries.

Performance analysis of cross-layer design with average PER constraint over MIMO fading channels

NASA Astrophysics Data System (ADS)

Dang, Xiaoyu; Liu, Yan; Yu, Xiangbin

2015-12-01

In this article, a cross-layer design (CLD) scheme for multiple-input and multiple-output system with the dual constraints of imperfect feedback and average packet error rate (PER) is presented, which is based on the combination of the adaptive modulation and the automatic repeat request protocols. The design performance is also evaluated over wireless Rayleigh fading channel. With the constraint of target PER and average PER, the optimum switching thresholds (STs) for attaining maximum spectral efficiency (SE) are developed. An effective iterative algorithm for finding the optimal STs is proposed via Lagrange multiplier optimisation. With different thresholds available, the analytical expressions of the average SE and PER are provided for the performance evaluation. To avoid the performance loss caused by the conventional single estimate, multiple outdated estimates (MOE) method, which utilises multiple previous channel estimation information, is presented for CLD to improve the system performance. It is shown that numerical simulations for average PER and SE are in consistent with the theoretical analysis and that the developed CLD with average PER constraint can meet the target PER requirement and show better performance in comparison with the conventional CLD with instantaneous PER constraint. Especially, the CLD based on the MOE method can obviously increase the system SE and reduce the impact of feedback delay greatly.

A regularized variable selection procedure in additive hazards model with stratified case-cohort design.

PubMed

Ni, Ai; Cai, Jianwen

2018-07-01

Case-cohort designs are commonly used in large epidemiological studies to reduce the cost associated with covariate measurement. In many such studies the number of covariates is very large. An efficient variable selection method is needed for case-cohort studies where the covariates are only observed in a subset of the sample. Current literature on this topic has been focused on the proportional hazards model. However, in many studies the additive hazards model is preferred over the proportional hazards model either because the proportional hazards assumption is violated or the additive hazards model provides more relevent information to the research question. Motivated by one such study, the Atherosclerosis Risk in Communities (ARIC) study, we investigate the properties of a regularized variable selection procedure in stratified case-cohort design under an additive hazards model with a diverging number of parameters. We establish the consistency and asymptotic normality of the penalized estimator and prove its oracle property. Simulation studies are conducted to assess the finite sample performance of the proposed method with a modified cross-validation tuning parameter selection methods. We apply the variable selection procedure to the ARIC study to demonstrate its practical use.

Defining SNAP by cross-sectional and longitudinal definitions of neurodegeneration.

PubMed

Wisse, L E M; Das, S R; Davatzikos, C; Dickerson, B C; Xie, S X; Yushkevich, P A; Wolk, D A

2018-01-01

Suspected non-Alzheimer's pathophysiology (SNAP) is a biomarker driven designation that represents a heterogeneous group in terms of etiology and prognosis. SNAP has only been identified by cross-sectional neurodegeneration measures, whereas longitudinal measures might better reflect "active" neurodegeneration and might be more tightly linked to prognosis. We compare neurodegeneration defined by cross-sectional 'hippocampal volume' only (SNAP/L-) versus both cross-sectional and longitudinal 'hippocampal atrophy rate' (SNAP/L+) and investigate how these definitions impact prevalence and the clinical and biomarker profile of SNAP in Mild Cognitive Impairment (MCI). 276 MCI patients from ADNI-GO/2 were designated amyloid "positive" (A+) or "negative" (A-) based on their florbetapir scan and neurodegeneration 'positive' or 'negative' based on cross-sectional hippocampal volume and longitudinal hippocampal atrophy rate. 74.1% of all SNAP participants defined by the cross-sectional definition of neurodegeneration also met the longitudinal definition of neurodegeneration, whereas 25.9% did not. SNAP/L+ displayed larger white matter hyperintensity volume, a higher conversion rate to dementia over 5 years and a steeper decline on cognitive tasks compared to SNAP/L- and the A- CN group. SNAP/L- had more abnormal values on neuroimaging markers and worse performance on cognitive tasks than the A- CN group, but did not show a difference in dementia conversion rate or longitudinal cognition. Using a longitudinal definition of neurodegeneration in addition to a cross-sectional one identifies SNAP participants with significant cognitive decline and a worse clinical prognosis for which cerebrovascular disease may be an important driver.

Spinal Orthoses: The Crucial Role of Comfort on Compliance of Wearing - Monocentric Prospective Pilot Study of Randomized Cross-Over Design.

PubMed

Herget, G W; Patermann, S; Strohm, P C; Zwingmann, J; Eichelberger, P; Südkamp, N P; Hirschmüller, A

2017-01-01

PURPOSE OF THE STUDY Various spine disorders are regularly treated by orthoses, and success of treatment depends on wearing these devices. In this study we examined the compliance, wear comfort, subjective stabilization and side effects associated with spinal orthoses using an individualized questionnaire and the Compact Short Form-12 Health Survey (SF-12). MATERIAL AND METHODS In this prospective pilot study of randomized cross-over design, twelve healthy volunteers with a mean age of 31.2 years wore three different types of orthoses, each for one week: A hyperextension brace (HB), a custom-made semirigid orthosis (SO) and a custom-made rigid orthosis (RO). The daily duration of wearing the orthosis was defined as primary endpoint; contentment was measured using an individualized questionnaire and the standardized SF-12. RESULTS In the study population calculated probability of wearing the HB and RO was between 0.2 und 38.5% (95% confidence interval). No volunteer wore the SO orthosis for the predefined time. The SO and RO each displayed high subjective stabilization, while the RO was more often associated with side effects like skin pressure marks than the SO. The need for rework due to discomfort was mainly necessary with the RO. We observed no substantial differences in feeling compression and sweating. Noteworthy, eight of 12 subjects complained of uncomfortable sternal pressure due to the upper pad of the HB. The SF-12: scores ranged from 52.1 to 48.6 on the physical (PCS), and from 53.7 to 50.8 on the mental component score (MCS), demonstrating an influence on QoL. DISCUSSION AND CONCLUSIONS The design as well as the orthosis itself influence the compliance of wearing and exert a moderate negative, but acceptable impact on QoL. The SO appeared to correlate with the best overall compromise between comfort and subjective stabilization. Further investigations are necessary in patients with spinal diseases, for whom the effect of orthosis wearing may surpass the potential discomfort. Key words: thoracolumbar spine, orthoses, SF-12 - Quality of Life - QoL, comfort, compliance.

Impact of Different e-Cigarette Generation and Models on Cognitive Performances, Craving and Gesture: A Randomized Cross-Over Trial (CogEcig).

PubMed

Caponnetto, Pasquale; Maglia, Marilena; Cannella, Maria Concetta; Inguscio, Lucio; Buonocore, Mariachiara; Scoglio, Claudio; Polosa, Riccardo; Vinci, Valeria

2017-01-01

Introduction: Most electronic-cigarettes (e-cigarette) are designed to look like traditional cigarettes and simulate the visual, sensory, and behavioral aspects of smoking traditional cigarettes. This research aimed to explore whether different e-cigarette models and smokers' usual classic cigarettes can impact on cognitive performances, craving and gesture. Methods: The study is randomized cross-over trial designed to compare cognitive performances, craving, and gesture in subjects who used first generation electronic cigarettes, second generation electronic cigarettes with their usual cigarettes. (Trial registration: ClinicalTrials.gov number NCT01735487). Results: Cognitive performance was not affected by "group condition." Within-group repeated measures analyses showed a significant time effect, indicating an increase of participants' current craving measure in group "usual classic cigarettes (group C)," "disposable cigalike electronic cigarette loaded with cartridges with 24 mg nicotine (group H), second generation electronic cigarette, personal vaporizer model Ego C, loaded with liquid nicotine 24 mg (group E). Measures of gesture not differ over the course of the experiment for all the products under investigation Conclusion: All cognitive measures attention, executive function and working memory are not influenced by the different e-cigarette and gender showing that in general electronics cigarettes could become a strong support also from a cognitive point of view for those who decide to quit smoking. It seems that not only craving and other smoke withdrawal symptoms but also cognitive performance is not only linked to the presence of nicotine; this suggests that the reasons behind the dependence and the related difficulty to quit smoking needs to be looked into also other factors like the gesture. www.ClinicalTrials.gov, identifier NCT01735487.

Impact of Different e-Cigarette Generation and Models on Cognitive Performances, Craving and Gesture: A Randomized Cross-Over Trial (CogEcig)

PubMed Central

Caponnetto, Pasquale; Maglia, Marilena; Cannella, Maria Concetta; Inguscio, Lucio; Buonocore, Mariachiara; Scoglio, Claudio; Polosa, Riccardo; Vinci, Valeria

2017-01-01

Introduction: Most electronic-cigarettes (e-cigarette) are designed to look like traditional cigarettes and simulate the visual, sensory, and behavioral aspects of smoking traditional cigarettes. This research aimed to explore whether different e-cigarette models and smokers' usual classic cigarettes can impact on cognitive performances, craving and gesture. Methods: The study is randomized cross-over trial designed to compare cognitive performances, craving, and gesture in subjects who used first generation electronic cigarettes, second generation electronic cigarettes with their usual cigarettes. (Trial registration: ClinicalTrials.gov number NCT01735487). Results: Cognitive performance was not affected by “group condition.” Within-group repeated measures analyses showed a significant time effect, indicating an increase of participants' current craving measure in group “usual classic cigarettes (group C),” “disposable cigalike electronic cigarette loaded with cartridges with 24 mg nicotine (group H), second generation electronic cigarette, personal vaporizer model Ego C, loaded with liquid nicotine 24 mg (group E). Measures of gesture not differ over the course of the experiment for all the products under investigation Conclusion: All cognitive measures attention, executive function and working memory are not influenced by the different e-cigarette and gender showing that in general electronics cigarettes could become a strong support also from a cognitive point of view for those who decide to quit smoking. It seems that not only craving and other smoke withdrawal symptoms but also cognitive performance is not only linked to the presence of nicotine; this suggests that the reasons behind the dependence and the related difficulty to quit smoking needs to be looked into also other factors like the gesture. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT01735487. PMID:28337155

Controlled irrigation of a structured packing as a method for increasing the efficiency of liquid mixture separation in the distillation column

NASA Astrophysics Data System (ADS)

Pavlenko, A. N.; Zhukov, V. E.; Pecherkin, N. I.; Nazarov, A. D.; Li, X.; Li, H.; Gao, X.; Sui, H.

2017-09-01

The use of modern structured packing in the distillation columns allows much more even distribution of the liquid film over the packing surface, but it does not completely solve the problem of uniform distribution of flow parameters over the entire height of the packing. Negative stratification of vapor along the packing height caused by different densities of vapor mixture components and higher temperature in the lower part of the column leads to formation of large-scale maldistributions of temperature and mixture composition over the column cross-section even under the conditions of uniform irrigation of packing with liquid. In these experiments, the idea of compensatory action of liquid distributor on the large-scale maldistribution of mixture composition over the column cross-section was implemented. The experiments were carried out in the distillation column with the diameter of 0.9 m on 10 layers of the Mellapak 350Y packing with the total height of 2.1 m. The mixture of R-21 and R-114 was used as the working mixture. To irrigate the packing, the liquid distributorr with 126 independently controlled solenoid valves overlapping the holes with the diameter of 5 mm, specially designed by the authors, was used. Response of the column to the action of liquid distributor was observed in real time according to the indications of 3 groups of thermometers mounted in 3 different cross-sections of the column. The experiments showed that the minimal correction of the drip point pattern in the controlled liquid distributor can significantly affect the pattern of flow parameter distribution over the cross-section and height of the mass transfer surface and increase separation efficiency of the column within 20%.

Combined N-of-1 trials to investigate mexiletine in non-dystrophic myotonia using a Bayesian approach; study rationale and protocol.

PubMed

Stunnenberg, Bas C; Woertman, Willem; Raaphorst, Joost; Statland, Jeffrey M; Griggs, Robert C; Timmermans, Janneke; Saris, Christiaan G; Schouwenberg, Bas J; Groenewoud, Hans M; Stegeman, Dick F; van Engelen, Baziel G M; Drost, Gea; van der Wilt, Gert Jan

2015-03-25

To obtain evidence for the clinical and cost-effectiveness of treatments for patients with rare diseases is a challenge. Non-dystrophic myotonia (NDM) is a group of inherited, rare muscle diseases characterized by muscle stiffness. The reimbursement of mexiletine, the expert opinion drug for NDM, has been discontinued in some countries due to a lack of independent randomized controlled trials (RCTs). It remains unclear however, which concessions can be accepted towards the level 1 evidence needed for coverage decisions, in rare diseases. Considering the large number of rare diseases with a lack of treatment evidence, more experience with innovative trial designs is needed. Both NDM and mexiletine are well suited for an N-of-1 trial design. A Bayesian approach allows for the combination of N-of-1 trials, which enables the assessment of outcomes on the patient and group level simultaneously. We will combine 30 individual, double-blind, randomized, placebo-controlled N-of-1 trials of mexiletine (600 mg daily) vs. placebo in genetically confirmed NDM patients using hierarchical Bayesian modeling. Our results will be compared and combined with the main results of an international cross-over RCT (mexiletine vs. placebo in NDM) published in 2012 that will be used as an informative prior. Similar criteria of eligibility, treatment regimen, end-points and measurement instruments are employed as used in the international cross-over RCT. The treatment of patients with NDM with mexiletine offers a unique opportunity to compare outcomes and efficiency of novel N-of-1 trial-based designs and conventional approaches in producing evidence of clinical and cost-effectiveness of treatments for patients with rare diseases. ClinicalTrials.gov Identifier: NCT02045667.

How can you capture cultural dynamics?

PubMed Central

Kashima, Yoshihisa

2014-01-01

Cross-cultural comparison is a critical method by which we can examine the interaction between culture and psychological processes. However, comparative methods tend to overlook cultural dynamics – the formation, maintenance, and transformation of cultures over time. The present article gives a brief overview of four different types of research designs that have been used to examine cultural dynamics in the literature: (1) cross-temporal methods that trace medium- to long-term changes in a culture; (2) cross-generational methods that explore medium-term implications of cultural transmission; (3) experimental simulation methods that investigate micro-level mechanisms of cultural dynamics; and (4) formal models and computer simulation methods often used to investigate long-term and macro-level implications of micro-level mechanisms. These methods differ in terms of level of analysis for which they are designed (micro vs. macro-level), scale of time for which they are typically used (short-, medium-, or long-term), and direction of inference (deductive vs. empirical method) that they imply. The paper describes examples of these methods, discuss their strengths and weaknesses, and point to their complementarity in inquiries about cultural change. Because cultural dynamics research is about meaning over time, issues deriving from interpretation of meaning and temporal distance between researchers and objects of inquiry can pose threats to the validity of the research and its findings. The methodological question about hermeneutic circle is recalled and further inquiries are encouraged. PMID:25309476

How older people in the United States and Germany fared in the growth years of the 1980s: a cross-sectional versus a longitudinal view.

PubMed

Burkhauser, R V; Cutts, A C; Lillard, D R

1999-09-01

The goal of the study was to show that cross-sectional and longitudinal data yield dramatically different answers to a basic question: "How did older persons fare in the recovery years of the 1980s?" The United States Panel Study of Income Dynamics and the German Socio-Economic Panel are used cross-sectionally to capture changes in the economic well-being of older persons in the trough and peak years of the 1980s business cycle, and longitudinally to trace how the economic well-being of a given cohort of older persons changed over those years. Kernel density estimation is then used to show how the distribution of economic well-being of these populations changed over these years. Cross-sectional comparisons confirm that persons aged 65 and over in the peak year were better off than persons aged 65 and over in the trough year in both countries. Longitudinal comparisons, however, show that persons aged 65 and over in the trough year who survived to the peak year received a substantially smaller share of the rewards of economic recovery than cross-sectional comparisons imply. Moreover, the entire income distribution of older persons in the United States shifted downwards. Compositional changes in the cross-sectional data, caused by the entry of high-income persons who are young in the peak year but old in the trough year, obscure the decline in the economic well-being of the cohort of older persons who survived the trough year, in cross-sectional comparisons of older populations in the United States in the 1980s.

Understanding Cross-Cultural Meaning through Visual Media.

ERIC Educational Resources Information Center

Hedberg, John G.; Brown, Ian

2002-01-01

Discusses cultural differences in Web site design for cross-cultural contexts and describes a study of Masters Degree students in Hong Kong that investigated their perceptions of Web learning environments that had been designed in Australia and delivered into Hong Kong and China. Considers the appropriateness of western interface design…

The Design and Analysis of Helium Turbine Expander Impeller with a Given All-Over-Controlled Vortex Distribution

NASA Astrophysics Data System (ADS)

Liu, Xiaodong; Fu, Bao; Zhuang, Ming

2014-03-01

To make the large-scale helium cryogenic system of fusion device EAST (experimental advanced super-conducting tokamak) run stably, as the core part, the helium turbine expander must meet the requirement of refrigeration capacity. However, previous designs were based on one dimension flow to determine the average fluid parameters and geometric parameters of impeller cross-sections, so that it could not describe real physical processes in the internal flow of the turbine expander. Therefore, based on the inverse proposition of streamline curvature method in the context of quasi-three-dimensional flows, the all-over-controlled vortex concept was adopted to design the impeller under specified condition. The wrap angle of the impeller blade and the whole flow distribution on the meridian plane were obtained; meanwhile the performance of the designed impeller was analyzed. Thus a new design method is proposed here for the inverse proposition of the helium turbine expander impeller.

Multimodal ophthalmic imaging using handheld spectrally encoded coherence tomography and reflectometry (SECTR)

NASA Astrophysics Data System (ADS)

Leeburg, Kelsey C.; El-Haddad, Mohamed T.; Malone, Joseph D.; Terrones, Benjamin D.; Tao, Yuankai K.

2018-02-01

Scanning laser ophthalmoscopy (SLO) provides high-speed, noninvasive en face imaging of the retinal fundus. Optical coherence tomography (OCT) is the current "gold-standard" for ophthalmic diagnostic imaging and enables depth-resolved visualization of ophthalmic structures and image-based surrogate biomarkers of disease. We present a compact optical and mechanical design for handheld spectrally encoded coherence tomography and reflectometry (SECTR) for multimodality en face spectrally encoded reflectometry (SER) and cross-sectional OCT imaging. We custom-designed a double-pass telecentric scan lens, which halves the size of 4-f optical relays and allowed us to reduce the footprint of our SECTR scan-head by a factor of >2.7x (volume) over our previous design. The double-pass scan lens was optimized for diffraction-limited performance over a +/-10° scan field. SECTR optics and optomechanics were combined in a compact rapid-prototyped enclosure with dimensions 87 x 141.8 x 137 mm (w x h x d). SECTR was implemented using a custom-built 400 kHz 1050 nm swept-source. OCT and SER were simultaneously digitized on dual input channels of a 4 GS/s digitizer at 1.4 GS/s per channel. In vivo human en face SER and cross-sectional OCT images were acquired at 350 fps. OCT volumes of 1000 B-scans were acquired in 2.86 s. We believe clinical translation of our compact handheld design will benefit point-of-care ophthalmic diagnostics in patients who are unable to be imaged on conventional slit-lamp based systems, such as infants and the bedridden. When combined with multi-volumetric registration methods, handheld SECTR will have advantages in motion-artifact free imaging over existing handheld technologies.

The CMS Level-1 Calorimeter Trigger for LHC Run II

NASA Astrophysics Data System (ADS)

Sinthuprasith, Tutanon

2017-01-01

The phase-1 upgrades of the CMS Level-1 calorimeter trigger have been completed. The Level-1 trigger has been fully commissioned and it will be used by CMS to collect data starting from the 2016 data run. The new trigger has been designed to improve the performance at high luminosity and large number of simultaneous inelastic collisions per crossing (pile-up). For this purpose it uses a novel design, the Time Multiplexed Design, which enables the data from an event to be processed by a single trigger processor at full granularity over several bunch crossings. The TMT design is a modular design based on the uTCA standard. The architecture is flexible and the number of trigger processors can be expanded according to the physics needs of CMS. Intelligent, more complex, and innovative algorithms are now the core of the first decision layer of CMS: the upgraded trigger system implements pattern recognition and MVA (Boosted Decision Tree) regression techniques in the trigger processors for pT assignment, pile up subtraction, and isolation requirements for electrons, and taus. The performance of the TMT design and the latency measurements and the algorithm performance which has been measured using data is also presented here.

Microbial mutagenic effects of the DNA minor groove binder pibenzimol (Hoechst 33258) and a series of mustard analogues.

PubMed

Ferguson, L R; Denny, W A

1995-06-01

A series of aniline mustards and half-mustards targeted to DNA by linkage (through a polymethylene chain) to the bisbenzimidazole chromophore of pibenzimol (Hoechst 33258) have been evaluated for their mutagenic properties, as estimated in three strains of Salmonella typhimurium, and for their mitotic crossing-over and petite mutagenesis activities in Saccharomyces cerevisiae strain D5. Agarose gel electrophoresis studies showed that only the derivative with the longest linker chain cross-linked DNA, with the remaining compounds being monoalkylators. The parent (non-alkylator) minor groove binding ligand (Hoechst 33258) was inactive in the bacterial strains TA98 or TA100 but weakly mutagenic in TA102, and caused neither mitotic crossing-over nor 'petite' mutagenesis in yeast. Aniline half-mustard itself (monoalkylator) was an effective base-pair substitution mutagen (events in S. typhimurium strain TA100) with some frameshift mutagenesis activity in TA98, but showed only weak effects in the yeast assays, whereas aniline mustard (cross-linker) was inactive in these bacterial systems but caused substantial amounts of mitotic crossing-over in yeast. The composite molecules studied here showed effects more characteristic of the minor groove binding chromophore than of alkylating moieties. All showed weak mutagenic activity in TA102 and none in TA98. The only compound to show significant mitotic crossing-over ability was the long-chain derivative which cross-linked DNA. For most of the compounds, the mutagenicity data provided no supportive evidence for DNA alkylation. Since other evidence suggests this does occur readily, it is likely to have a different target to that seen with untargeted aniline mustards. The significant antitumor activity and low mutagenic potential shown by these compounds make them worthy of further study.

A New ECR Ion Source for Nuclear Astrophysics Studies

NASA Astrophysics Data System (ADS)

Cesaratto, John M.

2008-10-01

The Laboratory for Experimental Nuclear Astrophysics (LENA) is a low energy facility designed to study nuclear reactions of astrophysical interest at energies which are important for nucleosysthesis. In general, these reactions have extremely small cross sections, requiring intense beams and efficient detection systems. Recently, a new, high intensity electron-cyclotron-resonance (ECR) ion source has been constructed (based on a design by Wills et al.[1]), which represents a substantial improvement in the capabilities of LENA. Beam is extracted from an ECR plasma excited at 2.45 GHz and confined by an array of permanent magnets. It has produced H^+ beams in excess of 1 mA on target over the energy range 100 - 200 keV, which greatly increases our ability to measure small cross sections. Initial measurements will focus on the ^23Na(p,γ)^24Mg reaction, which is of interest in a variety of astrophysical scenarios. The present uncertainty in the rate of this reaction is the result of an unobserved resonance expected at Elab =144 keV, which should be detectable using beams from the new ECR source. In collaboration with Arthur E. Champagne and Thomas B. Clegg, University of North Carolina, Chapel Hill and TUNL. [3pt] [1] J. S. C. Wills et al., Rev. Sci. Instrum. 69, 65 (1999).

SSRPrimer and SSR Taxonomy Tree: Biome SSR discovery

PubMed Central

Jewell, Erica; Robinson, Andrew; Savage, David; Erwin, Tim; Love, Christopher G.; Lim, Geraldine A. C.; Li, Xi; Batley, Jacqueline; Spangenberg, German C.; Edwards, David

2006-01-01

Simple sequence repeat (SSR) molecular genetic markers have become important tools for a broad range of applications such as genome mapping and genetic diversity studies. SSRs are readily identified within DNA sequence data and PCR primers can be designed for their amplification. These PCR primers frequently cross amplify within related species. We report a web-based tool, SSR Primer, that integrates SPUTNIK, an SSR repeat finder, with Primer3, a primer design program, within one pipeline. On submission of multiple FASTA formatted sequences, the script screens each sequence for SSRs using SPUTNIK. Results are then parsed to Primer3 for locus specific primer design. We have applied this tool for the discovery of SSRs within the complete GenBank database, and have designed PCR amplification primers for over 13 million SSRs. The SSR Taxonomy Tree server provides web-based searching and browsing of species and taxa for the visualisation and download of these SSR amplification primers. These tools are available at . PMID:16845092

SSRPrimer and SSR Taxonomy Tree: Biome SSR discovery.

PubMed

Jewell, Erica; Robinson, Andrew; Savage, David; Erwin, Tim; Love, Christopher G; Lim, Geraldine A C; Li, Xi; Batley, Jacqueline; Spangenberg, German C; Edwards, David

2006-07-01

Simple sequence repeat (SSR) molecular genetic markers have become important tools for a broad range of applications such as genome mapping and genetic diversity studies. SSRs are readily identified within DNA sequence data and PCR primers can be designed for their amplification. These PCR primers frequently cross amplify within related species. We report a web-based tool, SSR Primer, that integrates SPUTNIK, an SSR repeat finder, with Primer3, a primer design program, within one pipeline. On submission of multiple FASTA formatted sequences, the script screens each sequence for SSRs using SPUTNIK. Results are then parsed to Primer3 for locus specific primer design. We have applied this tool for the discovery of SSRs within the complete GenBank database, and have designed PCR amplification primers for over 13 million SSRs. The SSR Taxonomy Tree server provides web-based searching and browsing of species and taxa for the visualisation and download of these SSR amplification primers. These tools are available at http://bioinformatics.pbcbasc.latrobe.edu.au/ssrdiscovery.html.

Predictors of over-the-counter medication: A cross-sectional Indian study.

PubMed

Panda, Abinash; Pradhan, Supriya; Mohapatro, Gurukrushna; Kshatri, Jaya Singh

2017-01-01

The determinants of over-the-counter (OTC) medication need to be understood to design adequate drug information policies. To determine the prevalence and predictors of OTC medication among the adult population of Berhampur town in Odisha, India. It was a prospective, cross-sectional, observational study carried out in the private retail pharmacy on a convenience sample of 880 adults over a period of 6 months at Berhampur, Odisha, India. Medication use behavior was explored using a data collection form that had three parts. The first part captured data on the sociodemographic characteristics of drug consumers. The second and third part collected data on drug history and attitude toward the available health-care facility, respectively. Descriptive statistics was used to represent the prevalence of OTC medication. Odds ratio and 95% confidence intervals (CIs) were used to determine the predictors of OTC medication. The overall prevalence of OTC medication use was 18.72% (95% CI: 15.34-47.16%). Younger age, male gender, lower income, and poor lifestyle were the predictors of OTC medication. Perception of poor accessibility to health care, the presence of chronic diseases and having a symptom count of more than two significantly increased the likelihood of OTC medication ( P < 0.05). Sociodemographic profile, drug history, and attitude toward health-care availability in the locality can predict OTC medication behavior. Interventions aimed at changing the perceptions of the public regarding accessibility, affordability of the health care is likely to influence OTC medication behavior and make it safer.

Modeling time-to-event (survival) data using classification tree analysis.

PubMed

Linden, Ariel; Yarnold, Paul R

2017-12-01

Time to the occurrence of an event is often studied in health research. Survival analysis differs from other designs in that follow-up times for individuals who do not experience the event by the end of the study (called censored) are accounted for in the analysis. Cox regression is the standard method for analysing censored data, but the assumptions required of these models are easily violated. In this paper, we introduce classification tree analysis (CTA) as a flexible alternative for modelling censored data. Classification tree analysis is a "decision-tree"-like classification model that provides parsimonious, transparent (ie, easy to visually display and interpret) decision rules that maximize predictive accuracy, derives exact P values via permutation tests, and evaluates model cross-generalizability. Using empirical data, we identify all statistically valid, reproducible, longitudinally consistent, and cross-generalizable CTA survival models and then compare their predictive accuracy to estimates derived via Cox regression and an unadjusted naïve model. Model performance is assessed using integrated Brier scores and a comparison between estimated survival curves. The Cox regression model best predicts average incidence of the outcome over time, whereas CTA survival models best predict either relatively high, or low, incidence of the outcome over time. Classification tree analysis survival models offer many advantages over Cox regression, such as explicit maximization of predictive accuracy, parsimony, statistical robustness, and transparency. Therefore, researchers interested in accurate prognoses and clear decision rules should consider developing models using the CTA-survival framework. © 2017 John Wiley & Sons, Ltd.

LunarCubes: Application of the Cubesat Paradigm to Lunar Missions

NASA Technical Reports Server (NTRS)

Clark, P. E.; MacDowall, R.; Reuter, D.; Mauk, R.; Patel, D.; Hudeck, J.; Altunc, S.; Mentzel, E.; Hernandez, A.; Farrell, W.;

A randomized cross-over controlled study on cognitive rehabilitation of instrumental activities of daily living in Alzheimer disease.

PubMed

Thivierge, Stéphanie; Jean, Léonie; Simard, Martine

2014-11-01

The goal of the study was to investigate the effectiveness of a memory rehabilitation program to re-learn instrumental activities of daily living (IADLs) in patients with Alzheimer disease (AD). This was a 6-month block-randomized cross-over controlled study. All evaluation and training sessions were performed at each patient's home. Twenty participants with mild to moderate AD. The trained IADL was chosen by the patient and his/her caregiver in order to target the patient's needs and interests. Participants were trained twice a week for 4 weeks with the errorless learning (ELL) and spaced retrieval (SR) cognitive techniques. After training, there were several follow-ups over a period of at least 3 months. Performance on the trained IADL was assessed by a Direct Measure of Training (DMT), an observational instrument adapted from a well-validated scale. General cognitive function, everyday memory functioning, quality of life, neuropsychiatric symptoms and ADL/IADL of patients, as well as the caregiver's burden were assessed as secondary outcomes. A statistical significant difference was found between the trained and untrained groups on the DMT immediately following the intervention. Improvements were maintained for a 3-month period. The training did not have effects on any other measures. The present study showed that it is possible for AD patients to relearn significant IADLs with the ELL and SR techniques and to maintain these gains during at least 3 months. The findings of this study emphasize the importance to design robust but individualized intervention tailored on patients' particular needs. Copyright © 2014 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Impact of inter-genotypic recombination and probe cross-reactivity on the performance of the Abbott RealTime HCV Genotype II assay for hepatitis C genotyping.

PubMed

Sridhar, Siddharth; Yip, Cyril C Y; Chan, Jasper F W; To, Kelvin K W; Cheng, Vincent C C; Yuen, Kwok-Yung

2018-05-01

The Abbott RealTime HCV Genotype II assay (Abbott-RT-HCV assay) is a real-time PCR based genotyping method for hepatitis C virus (HCV). This study measured the impact of inter-genotypic recombination and probe cross-reactivity on the performance of the Abbott-RT-HCV assay. 517 samples were genotyped using the Abbott-RT-HCV assay over a one-year period, 34 (6.6%) were identified as HCV genotype 1 without further subtype designation raising the possibility of inaccurate genotyping. These samples were subjected to confirmatory sequencing. 27 of these 34 (79%) samples were genotype 1b while five (15%) were genotype 6. One HCV isolate was an inter-genotypic 1a/4o recombinant. This is a novel natural HCV recombinant that has never been reported. Inter-genotypic recombination and probe cross-reactivity can affect the accuracy of the Abbott-RT-HCV assay, both of which have significant implications on antiviral regimen choice. Confirmatory sequencing of ambiguous results is crucial for accurate genotyping. Copyright © 2018 Elsevier Inc. All rights reserved.

Medical students' attitudes towards peer physical examination: findings from an international cross-sectional and longitudinal study.

PubMed

Rees, Charlotte E; Wearn, Andy M; Vnuk, Anna K; Sato, Toshio J

2009-03-01

Although studies have begun to shed light on medical students' attitudes towards peer physical examination (PPE), they have been conducted at single sites, and have generally not examined changes in medical students' attitudes over time. Employing both cross-sectional and longitudinal designs, the current study examines medical students' attitudes towards PPE at schools from different geographical and cultural regions and assess changes in their attitudes over their first year of medical study. Students at six schools (Peninsula, UK; Durham, UK; Auckland, New Zealand; Flinders, Australia; Sapporo, Japan and Li Ka Shing, Hong Kong) completed the Examining Fellow Students (EFS) questionnaire near the start of their academic year (T1), and students at four schools (Peninsula, Durham, Auckland and Flinders) completed the EFS for a second time, around the end of their academic year (T2). Univariate and multivariate analyses revealed a high level of acceptance for PPE of non-intimate body regions amongst medical students from all schools (greater than 83%, hips, at T1 and 94.5%, hips and upper body, at T2). At T1 and T2, students' willingness to engage in PPE was associated with their gender, ethnicity, religiosity and school. Typically, students least comfortable with PPE at T1 and T2 were female, non-white, religious and studying at Auckland. Although students' attitudes towards PPE were reasonably stable over their first year of study, and after exposure to PPE, we did find some statistically significant differences in attitudes between T1 and T2. Interestingly, attitude changes were consistently predicted by gender, even when controlling for school. While male students' attitudes towards PPE were relatively stable over time, females' attitudes were changeable. In this paper, we discuss our findings in light of existing research and theory, and discuss their implications for educational practice and further research.

Influence of shift work on the physical work capacity of Tunisian nurses: a cross-sectional study in two university hospitals.

PubMed

Merchaoui, Irtyah; Bouzgarrou, Lamia; Mnasri, Ahlem; Mghanem, Mounir; Akrout, Mohamed; Malchaire, Jacques; Chaari, Neila

2017-01-01

This study has been performed to determine the influence of rotating shift work on physical working capacity of Tunisian nurses and to design recommendations to managers so that they implement effective preventive measures. It is a cross-sectional design using a standardized questionnaire and many physical capacity tests on a representative sample of 1181 nurses and nursing assistants from two university hospital centers of the school of Medicine of Monastir located in the Tunisian Sahel. 293 participants have been recruited by stratified random sampling according to gender and departments. Maximum Grip strength, 30s sit-to-stand test, one leg test, Fingertip-to-Floor test, Saltsa test and peak expiratory flow were used to assess physical capacity. Work ability was assessed through the workability index. Mental and physical loads were heavily perceived in shift healthcare workers (p=0.01; p=0.02). The maximum grip force was stronger in rotating shift work nurses (p=0.0001). Regarding to the seniority subgroups in each kind of work schedule, the Body Mass Index was increasing with seniority in both schedules. All the physical tests, were better in less-than-ten-year groups. Peak Flow and grip strength were significantly better in less-than-ten-year seniority in shift work group. There is a need to improve the design of the existing shift systems and to reduce as much as possible shift schedule as well as to avoid shift schedule for over-10-year-seniority nurses.

Global Research Trends on Early-Life Feeding Practices and Early Childhood Caries: a Systematic Review

PubMed Central

Cheng, Ashley

2014-01-01

Objective Describe the epidemiologic literature related to early-life feeding practices and early childhood caries (ECC) with regard to publication attributes and trends in these attributes over time. Methods Systematic literature review including electronic and manual searches (in BIOSIS, CINAHL, Cochrane Library, LILACS, MEDLINE, Web of Science, and WHOLIS), covering the years 1990–2013. Attributes of publications meeting a priori inclusion criteria were abstracted and organized by global region and trends over time. Attributes included country of origin and study design of included publications and age and caries prevalence of the populations studied. Results 244 publications drawn from 196 independent study populations were included. The number of publications and the countries represented increased over time, although some world regions remained underrepresented. Most publications were cross sectional (75%); while this percentage remained fairly constant over time, the percentage of studies to account for confounding factors increased. Publications varied with respect to the caries experience and age range of children included in each study. Conclusions Publication productivity regarding feeding practices and ECC research has grown, but this growth has not been evenly distributed globally. Individual publication attributes (i.e. methods and context) can differ significantly and should be considered when interpreting and synthesizing the literature. PMID:25328911

Drug-Triggered and Cross-Linked Self-Assembling Nanofibrous Hydrogels

PubMed Central

Kumar, Vivek A.; Shi, Siyu; Wang, Benjamin K.; Li, I-Che; Jalan, Abhishek A.; Sarkar, Biplab; Wickremasinghe, Navindee C.; Hartgerink, Jeffrey D.

2015-01-01

Self-assembly of multidomain peptides (MDP) can be tailored to carry payloads that modulate the extracellular environment. Controlled release of growth factors, cytokines, and small-molecule drugs allows for unique control of in vitro and in vivo responses. In this study, we demonstrate this process of ionic cross-linking of peptides using multivalent drugs to create hydrogels for sustained long-term delivery of drugs. Using phosphate, heparin, clodronate, trypan, and suramin, we demonstrate the utility of this strategy. Although all multivalent anions result in good hydrogel formation, demonstrating the generality of this approach, suramin led to the formation of the best hydrogels per unit concentration and was studied in greater detail. Suramin ionically cross-linked MDP into a fibrous meshwork as determined by scanning and transmission electron microscopy. We measured material storage and loss modulus using rheometry and showed a distinct increase in G′ and G″ as a function of suramin concentration. Release of suramin from scaffolds was determined using UV spectroscopy and showed prolonged release over a 30 day period. Suramin bioavailability and function were demonstrated by attenuated M1 polarization of THP-1 cells compared to positive control. Overall, this design strategy has allowed for the development of a novel class of polymeric delivery vehicles with generally long-term release and, in the case of suramin, cross-linked hydrogels that can modulate cellular phenotype. PMID:25831137

Entering New Territory: Crossing over to Fully Synchronous, E-Learning Courses

ERIC Educational Resources Information Center

Robertson, Lorayne; Hardman, Wendy

2012-01-01

A training module of six sessions was designed for professors in higher education who were transitioning to teaching synchronous, e-learning courses from formerly teaching in either asynchronous courses or in face-to-face courses. Since the participants were experienced educators, the boundary of their expertise to be extended was moving to the…

General study of asymmetrical crossed Czerny-Turner spectrometer.

PubMed

Tang, Ming; Fan, Xianguang; Wang, Xin; Xu, Yingjie; Que, Jing; He, Jian

2015-11-20

A study of the spectrum resolution, wavelength range, and primary aberration of the asymmetrical crossed Czerny-Turner spectrometer is presented by deducing the relationship between them and structural parameters of the spectrometer in a new way of thinking based on simple but effective geometric models. The analysis was verified in an experiment and simulation performed on the optical design program ZEMAX, and the obtained results agree with the analysis. Owing to the analysis, initial designed parameters of the spectrometer were given and then optimized by ZEMAX; with the instruction of the study, a small adjustment was made in the actual alignment to obtain the desired final spectrometer. The spectrometer successfully measured the last four characteristic peaks of the Raman spectrum of CCL4, which demonstrates that the research provides important guidance to the design and alignment of an asymmetrical crossed Czerny-Turner spectrometer.

Risk factors for adult overweight and obesity in the Quebec Family Study: have we been barking up the wrong tree?

PubMed

Chaput, Jean-Philippe; Leblanc, Claude; Pérusse, Louis; Després, Jean-Pierre; Bouchard, Claude; Tremblay, Angelo

2009-10-01

The aim of this study was to determine the independent contribution of previously reported risk factors for adult overweight and obesity. A cross-sectional (n=537) and a longitudinal (n=283; 6-year follow-up period) analysis was performed for nine risk factors for overweight and obesity assessed in adult participants (aged 18-64 years) of the Quebec Family Study (QFS). The main outcome measure was overweight/obesity, defined as a BMI>or=25 kg/m2. Using logistic regression analysis adjusted for age, sex, and socioeconomic status, short sleep duration, high disinhibition eating behavior, low dietary calcium intake, high susceptibility to hunger behavior, nonparticipation in high-intensity physical exercise, high dietary restraint behavior, nonconsumption of multivitamin and dietary supplements, high dietary lipid intake, and high alcohol intake were all significantly associated with overweight and obesity in the cross-sectional sample. The analysis of covariance adjusted for age, socioeconomic status, and all other risk factors revealed that only individuals characterized by short sleep duration, high disinhibition eating behavior, and low dietary calcium intake had significantly higher BMI compared to the reference category in both sexes. Over the 6-year follow-up period, short-duration sleepers, low calcium consumers, and those with a high disinhibition and restraint eating behavior score were significantly more likely to gain weight and develop obesity. These results show that excess body weight or weight gain results from a number of obesogenic behaviors that have received considerable attention over the past decade. They also indicate that the four factors, which have the best predictive potential of variations in BMI, be it in a cross-sectional or a longitudinal analytical design, do not have a "caloric value" per se.

Sport stacking in auditory and visual attention of grade 3 learners.

PubMed

Mortimer, J; Krysztofiak, J; Custard, S; McKune, A J

2011-08-01

The effect of sport stacking on auditory and visual attention in 32 Grade 3 children was examined using a randomised, cross-over design. Children were randomly assigned to a sport stacking (n=16) or arts/crafts group (n=16) with these activities performed over 3 wk. (12 30-min. sessions, 4 per week). This was followed by a 3-wk. wash-out period after which there was a cross-over and the 3-wk. intervention repeated, with the sports stacking group performing arts/crafts and the arts/crafts group performing sports stacking. Performance on the Integrated Visual and Auditory Continuous Performance Test, a measure of auditory and visual attention, was assessed before and after each of the 3-wk. interventions for each group. Comparisons indicated that sport stacking resulted in significant improvement in high demand function and fine motor regulation, while it caused a significant reduction in low demand function. Auditory and visual attention adaptations to sport stacking may be specific to the high demand nature of the task.

Methodology for safety optimization of highway cross-sections for horizontal curves with restricted sight distance.

PubMed

Ibrahim, Shewkar E; Sayed, Tarek; Ismail, Karim

2012-11-01

Several earlier studies have noted the shortcomings with existing geometric design guides which provide deterministic standards. In these standards the safety margin of the design output is generally unknown and there is little knowledge of the safety implications of deviating from the standards. To mitigate these shortcomings, probabilistic geometric design has been advocated where reliability analysis can be used to account for the uncertainty in the design parameters and to provide a mechanism for risk measurement to evaluate the safety impact of deviations from design standards. This paper applies reliability analysis for optimizing the safety of highway cross-sections. The paper presents an original methodology to select a suitable combination of cross-section elements with restricted sight distance to result in reduced collisions and consistent risk levels. The purpose of this optimization method is to provide designers with a proactive approach to the design of cross-section elements in order to (i) minimize the risk associated with restricted sight distance, (ii) balance the risk across the two carriageways of the highway, and (iii) reduce the expected collision frequency. A case study involving nine cross-sections that are parts of two major highway developments in British Columbia, Canada, was presented. The results showed that an additional reduction in collisions can be realized by incorporating the reliability component, P(nc) (denoting the probability of non-compliance), in the optimization process. The proposed approach results in reduced and consistent risk levels for both travel directions in addition to further collision reductions. Copyright © 2012 Elsevier Ltd. All rights reserved.

Influence of core design, production technique, and material selection on fracture behavior of yttria-stabilized tetragonal zirconia polycrystal fixed dental prostheses produced using different multilayer techniques: split-file, over-pressing, and manually built-up veneers.

PubMed

Mahmood, Deyar Jallal Hadi; Linderoth, Ewa H; Wennerberg, Ann; Vult Von Steyern, Per

2016-01-01

To investigate and compare the fracture strength and fracture mode in eleven groups of currently, the most commonly used multilayer three-unit all-ceramic yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) fixed dental prostheses (FDPs) with respect to the choice of core material, veneering material area, manufacturing technique, design of connectors, and radii of curvature of FDP cores. A total of 110 three-unit Y-TZP FDP cores with one intermediate pontic were made. The FDP cores in groups 1-7 were made with a split-file design, veneered with manually built-up porcelain, computer-aided design-on veneers, and over-pressed veneers. Groups 8-11 consisted of FDPs with a state-of-the-art design, veneered with manually built-up porcelain. All the FDP cores were subjected to simulated aging and finally loaded to fracture. There was a significant difference (P<0.05) between the core designs, but not between the different types of Y-TZP materials. The split-file designs with VITABLOCS(®) (1,806±165 N) and e.max(®) ZirPress (1,854±115 N) and the state-of-the-art design with VITA VM(®) 9 (1,849±150 N) demonstrated the highest mean fracture values. The shape of a split-file designed all-ceramic reconstruction calls for a different dimension protocol, compared to traditionally shaped ones, as the split-file design leads to sharp approximal indentations acting as fractural impressions, thus decreasing the overall strength. The design of a framework is a crucial factor for the load bearing capacity of an all-ceramic FDP. The state-of-the-art design is preferable since the split-file designed cores call for a cross-sectional connector area at least 42% larger, to have the same load bearing capacity as the state-of-the-art designed cores. All veneering materials and techniques tested in the study, split-file, over-press, built-up porcelains, and glass-ceramics are, with a great safety margin, sufficient for clinical use both anteriorly and posteriorly. Analysis of the fracture pattern shows differences between the milled veneers and over-pressed or built-up veneers, where the milled ones show numerically more veneer cracks and the other groups only show complete connector fractures.

The effect of sitting and calf activity on leg fluid and snoring.

PubMed

Singh, Bhajan; Yadollahi, Azadeh; Lyons, Owen; Alshaer, Hisham; Bradley, T Douglas

2017-06-01

Prolonged sitting may promote leg fluid retention that redistributes to the neck during sleep and contributes to snoring. This could be attenuated by calf activity while sitting. In 16 healthy non-obese subjects we measured leg fluid volume (LFV) below the knees using bioelectrical impedance while sitting for 4h, snoring using a portable BresoDx™ device, and Mallampati grade. Using a double cross-over study design, subjects were randomized to one of two arms and crossed-over one week later: control arm - no calf exercise while sitting; intervention arm - calf contraction against a pedal resistance while sitting. The effects of sitting±calf activity on LFV and snoring were compared. We found that LFV increased by 216±101.0ml (p<0.0001) after sitting. Calf activity while sitting attenuated LFV by 53.8ml (p<0.0001) and, in all five subjects with severe upper airway narrowing (Mallampati grade IV), reduced snoring duration (from 357±132.9 to 116.2±72.1s/h, p=0.02) suggesting reduced overnight rostral fluid shift to the neck. Copyright © 2017 Elsevier B.V. All rights reserved.

Amphetamine-type stimulants and HIV infection among men who have sex with men: implications on HIV research and prevention from a systematic review and meta-analysis

PubMed Central

Thu Vu, Nga Thi; Maher, Lisa; Zablotska, Iryna

2015-01-01

Introduction HIV infections and the use of amphetamine-type stimulants (ATS) among men who have sex with men (MSM) have been increasing internationally, but the role of ATS use as a co-factor for HIV infection remains unclear. We aimed to summarize the association between ATS use and HIV infection among MSM. Methods We conducted a systematic search of MEDLINE, EMBASE, GLOBAL HEALTH and PsycINFO for relevant English, peer-reviewed articles of quantitative studies published between 1980 and 25 April 2013. Pooled estimates of the association – prevalence rate ratios (PRR, cross-sectional studies), odds ratio (OR, case-control studies) and hazard ratio (HR, longitudinal studies), with 95% Confidence Intervals (CI) – were calculated using random-effects models stratified by study design and ATS group (meth/amphetamines vs. ecstasy). We assessed the existence of publication bias in funnel plots and checked for sources of heterogeneity using meta-regression and subgroup analysis. Results We identified 6710 article titles, screened 1716 abstracts and reviewed 267 full text articles. A total of 35 publications were eligible for data abstraction and meta-analysis, resulting in 56 records of ATS use. Most studies (31/35) were conducted in high-income countries. Published studies used different research designs, samples and measures of ATS use. The pooled association between meth/amphetamine use and HIV infection was statistically significant in all three designs (PRR=1.86; 95% CI: 1.57–2.17; OR=2.73; 95% CI: 2.16–3.46 and HR=3.43; 95% CI: 2.98–3.95, respectively, for cross-sectional, case-control and longitudinal studies). Ecstasy use was not associated with HIV infection in cross-sectional studies (PRR=1.15; 95% CI: 0.88–1.49; OR=3.04; 95% CI: 1.29–7.18 and HR=2.48; 95% CI: 1.42–4.35, respectively, for cross-sectional, case-control and longitudinal studies). Results in cross-sectional studies were highly heterogeneous due to issues with ATS measurement and different sampling frames. Conclusions While meth/amphetamine use was significantly associated with HIV infection among MSM in high-income countries in all study designs, evidence of the role of ecstasy in HIV infection was lacking in cross-sectional studies. Cross-sectional study design, measurement approaches and source populations may also be important modifiers of the strength and the direction of associations. Event-specific measure of individual drug is required to establish temporal relationship between ATS use and HIV infection. HIV prevention programmes targeting MSM should consider including interventions designed to address meth/amphetamine use. PMID:25609214

Understanding Gender, Creativity, and Entrepreneurial Intentions

ERIC Educational Resources Information Center

Smith, Ronda Marie; Sardeshmukh, Shruti R.; Combs, Gwendolyn M.

2016-01-01

Purpose: The purpose of this paper is to explore the complex relationships between gender and entrepreneurial intentions. Design/methodology/approach: This paper uses a two study design where the second study is a constructive replication of the first study. The first study uses a cross-sectional design, while the second uses a design where data…

Effects of ultrafine particles on the allergic inflammation in the lung of asthmatics: results of a double-blinded randomized cross-over clinical pilot study

PubMed Central

2014-01-01

Background Epidemiological and experimental studies suggest that exposure to ultrafine particles (UFP) might aggravate the allergic inflammation of the lung in asthmatics. Methods We exposed 12 allergic asthmatics in two subgroups in a double-blinded randomized cross-over design, first to freshly generated ultrafine carbon particles (64 μg/m3; 6.1 ± 0.4 × 105 particles/cm3 for 2 h) and then to filtered air or vice versa with a 28-day recovery period in-between. Eighteen hours after each exposure, grass pollen was instilled into a lung lobe via bronchoscopy. Another 24 hours later, inflammatory cells were collected by means of bronchoalveolar lavage (BAL). (Trial registration: NCT00527462) Results For the entire study group, inhalation of UFP by itself had no significant effect on the allergen induced inflammatory response measured with total cell count as compared to exposure with filtered air (p = 0.188). However, the subgroup of subjects, which inhaled UFP during the first exposure, exhibited a significant increase in total BAL cells (p = 0.021), eosinophils (p = 0.031) and monocytes (p = 0.013) after filtered air exposure and subsequent allergen challenge 28 days later. Additionally, the potential of BAL cells to generate oxidant radicals was significantly elevated at that time point. The subgroup that was exposed first to filtered air and 28 days later to UFP did not reveal differences between sessions. Conclusions Our data demonstrate that pre-allergen exposure to UFP had no acute effect on the allergic inflammation. However, the subgroup analysis lead to the speculation that inhaled UFP particles might have a long-term effect on the inflammatory course in asthmatic patients. This should be reconfirmed in further studies with an appropriate study design and sufficient number of subjects. PMID:25204642

A Pilot Study of the Interface Design of Cross-Cultural Web Sites through Usability Testing of Multilanguage Web Sites and Determining the Preferences of Taiwanese and American Users

ERIC Educational Resources Information Center

Ku, David Tawei; Chang, Chia-Chi

2014-01-01

By conducting usability testing on a multilanguage Web site, this study analyzed the cultural differences between Taiwanese and American users in the performance of assigned tasks. To provide feasible insight into cross-cultural Web site design, Microsoft Office Online (MOO) that supports both traditional Chinese and English and contains an almost…

KSI's Cross Insulated Core Transformer Technology

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

Uhmeyer, Uwe

2009-08-04

Cross Insulated Core Transformer (CCT) technology improves on Insulated Core Transformer (ICT) implementations. ICT systems are widely used in very high voltage, high power, power supply systems. In an ICT transformer ferrite core sections are insulated from their neighboring ferrite cores. Flux leakage is present at each of these insulated gaps. The flux loss is raised to the power of stages in the ICT design causing output voltage efficiency to taper off with increasing stages. KSI's CCT technology utilizes a patented technique to compensate the flux loss at each stage of an ICT system. Design equations to calculate the fluxmore » compensation capacitor value are presented. CCT provides corona free operation of the HV stack. KSI's CCT based High Voltage power supply systems offer high efficiency operation, high frequency switching, low stored energy and smaller size over comparable ICT systems.« less

Exposure to polychlorinated biphenyls and the thyroid gland – examining and discussing possible longitudinal health effects in humans

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

Gaum, Petra M., E-mail: pgaum@ukaachen.de; Lang, Jessica; Esser, André

Background: Many previous studies have dealt with the effect of polychlorinated biphenyls (PCBs) on the thyroid gland, but their findings are inconsistent. One problem of these studies has been their use of cross-sectional designs. Objectives: The aim of the current study is to investigate longitudinal effects of PCBs on the thyroid gland, focusing on: morphological changes in thyroid tissue (i.e. thyroid volume), changes in thyroid hormones and in thyroid antibodies. Methods: A total of 122 individuals (M{sub age}=44.7) were examined over a period of four years (t{sup 1} until t{sup 4}). Medical history was collected via interviews, an ultrasound examinationmore » was performed and blood samples were taken to determine plasma PCB levels, thyroid stimulating hormone (TSH), free triiodthyronine (fT3), free thyroxine (fT4), thyroid peroxidase antibodies (TPOab), thyreoglobulin antibodies (TGab) and thyroid-stimulating hormone receptor antibodies (TSHRab). Rank correlation coefficients and mixed effect models were performed controlling for age and total lipids. Results: There were negative correlations between higher chlorinated biphenyls and fT3, cross-sectionally as well as longitudinally. We also found an interaction effect of higher-chlorinated PCBs over time for fT4 as well as TSHRab. In case of high exposure, a decrease in fT4 and an increase in TSHRab level were found over time. In regards to the other variables, our findings yielded no clear results in the examined time period. Conclusion: This is the first study to shows a PCB-related effect on fT3, fT4 and TSHRab over a four year period. The data also suggest that morphological and antibody findings remain inconsistent and do not allow for unambiguous interpretation. - Highlights: • This is a longitudinal study which includes data from four cross sections. • Higher-chlorinated biphenyls are negatively correlated with fT3. • There are interactions of time and higher-chlorinated biphenyls to TSHRab and fT4. • There is an interaction of time and dioxin-like polychlorinated biphenyls to fT4. • No consistent effects were found for thyroid volume, TSH, TPOab and TGab.« less

Mapping the Diagnosis Axis of an Interface Terminology to the NANDA International Taxonomy

PubMed Central

Juvé Udina, Maria-Eulàlia; Gonzalez Samartino, Maribel; Matud Calvo, Cristina

2012-01-01

Background. Nursing terminologies are designed to support nursing practice but, as with any other clinical tool, they should be evaluated. Cross-mapping is a formal method for examining the validity of the existing controlled vocabularies. Objectives. The study aims to assess the inclusiveness and expressiveness of the nursing diagnosis axis of a newly implemented interface terminology by cross-mapping with the NANDA-I taxonomy. Design/Methods. The study applied a descriptive design, using a cross-sectional, bidirectional mapping strategy. The sample included 728 concepts from both vocabularies. Concept cross-mapping was carried out to identify one-to-one, negative, and hierarchical connections. The analysis was conducted using descriptive statistics. Results. Agreement of the raters' mapping achieved 97%. More than 60% of the nursing diagnosis concepts in the NANDA-I taxonomy were mapped to concepts in the diagnosis axis of the new interface terminology; 71.1% were reversely mapped. Conclusions. Main results for outcome measures suggest that the diagnosis axis of this interface terminology meets the validity criterion of cross-mapping when mapped from and to the NANDA-I taxonomy. PMID:22830046

Mapping the Diagnosis Axis of an Interface Terminology to the NANDA International Taxonomy.

PubMed

Juvé Udina, Maria-Eulàlia; Gonzalez Samartino, Maribel; Matud Calvo, Cristina

2012-01-01

Background. Nursing terminologies are designed to support nursing practice but, as with any other clinical tool, they should be evaluated. Cross-mapping is a formal method for examining the validity of the existing controlled vocabularies. Objectives. The study aims to assess the inclusiveness and expressiveness of the nursing diagnosis axis of a newly implemented interface terminology by cross-mapping with the NANDA-I taxonomy. Design/Methods. The study applied a descriptive design, using a cross-sectional, bidirectional mapping strategy. The sample included 728 concepts from both vocabularies. Concept cross-mapping was carried out to identify one-to-one, negative, and hierarchical connections. The analysis was conducted using descriptive statistics. Results. Agreement of the raters' mapping achieved 97%. More than 60% of the nursing diagnosis concepts in the NANDA-I taxonomy were mapped to concepts in the diagnosis axis of the new interface terminology; 71.1% were reversely mapped. Conclusions. Main results for outcome measures suggest that the diagnosis axis of this interface terminology meets the validity criterion of cross-mapping when mapped from and to the NANDA-I taxonomy.

Simple, empirical approach to predict neutron capture cross sections from nuclear masses

NASA Astrophysics Data System (ADS)

Couture, A.; Casten, R. F.; Cakirli, R. B.

2017-12-01

Background: Neutron capture cross sections are essential to understanding the astrophysical s and r processes, the modeling of nuclear reactor design and performance, and for a wide variety of nuclear forensics applications. Often, cross sections are needed for nuclei where experimental measurements are difficult. Enormous effort, over many decades, has gone into attempting to develop sophisticated statistical reaction models to predict these cross sections. Such work has met with some success but is often unable to reproduce measured cross sections to better than 40 % , and has limited predictive power, with predictions from different models rapidly differing by an order of magnitude a few nucleons from the last measurement. Purpose: To develop a new approach to predicting neutron capture cross sections over broad ranges of nuclei that accounts for their values where known and which has reliable predictive power with small uncertainties for many nuclei where they are unknown. Methods: Experimental neutron capture cross sections were compared to empirical mass observables in regions of similar structure. Results: We present an extremely simple method, based solely on empirical mass observables, that correlates neutron capture cross sections in the critical energy range from a few keV to a couple hundred keV. We show that regional cross sections are compactly correlated in medium and heavy mass nuclei with the two-neutron separation energy. These correlations are easily amenable to predict unknown cross sections, often converting the usual extrapolations to more reliable interpolations. It almost always reproduces existing data to within 25 % and estimated uncertainties are below about 40 % up to 10 nucleons beyond known data. Conclusions: Neutron capture cross sections display a surprisingly strong connection to the two-neutron separation energy, a nuclear structure property. The simple, empirical correlations uncovered provide model-independent predictions of neutron capture cross sections, extending far from stability, including for nuclei of the highest sensitivity to r -process nucleosynthesis.

Implementation of knowledge-based palliative care in nursing homes and pre-post post evaluation by cross-over design: a study protocol.

PubMed

Ahlström, Gerd; Nilsen, Per; Benzein, Eva; Behm, Lina; Wallerstedt, Birgitta; Persson, Magnus; Sandgren, Anna

2018-03-22

The demography of the world is changing as the population is ageing. Because of this change to a higher proportion of older people, the WHO has called for improved palliative care for older persons. A large number of all deaths in the industrialised world occur while older people are living in nursing homes and therefore a key question becomes how the principles of palliative care can be implemented in that context. The aims of this study are: a) to describe a model of an educational intervention with the goal of implementing knowledge-based palliative care in nursing homes, and b) to describe the design of the evaluation of the effectiveness regarding the implementation of knowledge-based palliative care. A complex intervention is evaluated by means of a cross-over design. An educational intervention concerning palliative care consisting of five seminars during 6 months for staff and managers has been developed and conducted in 20 nursing homes in two counties. Before the intervention started, the feasibility was tested in a pilot study conducted in nursing homes not included in the main study. The intervention is evaluated through a non-randomized experimental design with intervention and control groups and pre- and post-assessments. The evaluation includes older persons living in nursing homes, next-of-kin, staff and managers. Data collection consists of quantitative methods such as questionnaires and register data and qualitative methods in the form of individual interviews, focus-group interviews and participant observations. The research will contribute to new knowledge about how to implement knowledge-based palliative care in a nursing home setting. A strength of this project is that the Medical Research Council framework of complex intervention is applied. The four recommended stages, Development, Feasibility and piloting, Evaluation and Implementation, are combined for the educational intervention, which functions as a strategy to achieve knowledge-based palliative care in the nursing homes. Implementation is always a question of change and a good theoretical understanding is needed for drawing valid conclusions about the causal mechanisms of change. The topic is highly relevant considering the world's ageing population. The data collection is completed and the analysis is ongoing. NCT02708498 .

Study on the preparation process of cross-linked porous cassava starch

NASA Astrophysics Data System (ADS)

Yin, Xiulian; You, Qinghong; Wan, Miaomiao; Zhang, Xuejuan; Dai, Chunhua

2017-04-01

Using cassava starch as raw material, preparation process of porous cross-linked cassava starch was studied. Using TSTP as cross-linking agents, Orthogonal design was applied for the optimization of cross-linked porous starch preparation process. The results showed that the opitmal conditions of cross-linked porous cassava starch were as follows: reaction temperature 45°C, reaction time 20 h, 1% of the amount of the enzyme, the enzyme ratio of 1:5, pH 5.50, substrate concentration of 40%.

The potential for improvement of outcomes by personalized insulin treatment of type 1 diabetes as assessed by analysis of single-patient data from a randomized controlled cross-over insulin trial.

PubMed

Pedersen-Bjergaard, Ulrik; Kristensen, Peter L; Beck-Nielsen, Henning; Nørgaard, Kirsten; Perrild, Hans; Christiansen, Jens S; Jensen, Tonny; Parving, Hans-Henrik; Thorsteinsson, Birger; Tarnow, Lise

2017-01-01

The evidence for optimal insulin treatment in type 1 diabetes is mainly based on randomised controlled trials applying a parallel-group design. Such trials yield robust general results but crucial individual treatment effects cannot be extracted. We aimed to assess the potential for further improvement of outcomes by personalized insulin therapy by analyzing data from a cross-over trial at individual level. Post hoc analysis of data from a two-year multicentre, prospective, randomised, open, blinded endpoint (PROBE) trial (the HypoAna trial). In a cross-over design 114 patients with type 1 diabetes and recurrent severe hypoglycemia were treated with basal-bolus therapy based on analog (detemir/aspart) or human (NPH/regular) insulin aiming at maintenance of baseline HbA1c levels. For each patient a superior outcome was defined as fewer events of severe hypoglycemia defined by need for third party treatment assistance or a more than 0.4% (4.4mmol/mol) lower HbA1c. Only one quarter had comparable outcome of the two treatments in terms of rate of severe hypoglycemia or HbA1c. Twice as many patients had superior outcome of analog-based as compared to human insulin-based insulin treatment. The rate of severe hypoglycemia with the superior treatment was lower compared to the rates obtained with analog insulin and with human insulin (0.67, 1.09, and 1.57 episode per patient-year, respectively (p<0.0001)). Personalized insulin treatment of type 1 diabetes based on single-patient evidence may improve outcomes significantly compared to a general treatment approach. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Post-electroconvulsive therapy recovery and reorientation time with methohexital and ketamine: a randomized, longitudinal cross-over design trial

PubMed Central

Yen, Tony; Khafaja, Mohamad; Lam, Nicholas; Crumbacher, James; Schrader, Ronald; Rask, John; Billstrand, Mary; Rothfork, Jacob; Abbott, Christopher C.

2014-01-01

Objectives Methohexital, a barbiturate anesthetic commonly used for electroconvulsive therapy (ECT), possesses dose-dependent anticonvulsant properties, and its use can interfere with effective seizure therapy in patients with high seizure thresholds. Ketamine, a NMDA-antagonist with epileptogenic properties not broadly used for ECT inductions, is a commonly used induction agent for general anesthesia. Recent studies suggest that the use of ketamine is effective in allowing successful ECT treatment in patients with high seizure thresholds without an increase in side-effects. In this preliminary study, we directly compared the recovery and re-orientation times of subjects receiving ketamine and methohexital for ECTs. Methods Twenty patients were randomized in a cross-over design to receive methohexital and ketamine for ECT inductions in alternating fashion for six trials. Primary outcome measures were recovery time (voluntary movement, respiratory effort, blood pressure, consciousness, and O2 saturation) and re-orientation time. Secondary outcome measures were individual recovery variables, side-effect occurrence, and seizure duration. Results: Overall recovery time was not significantly different between the two treatment arms (F(1,17) = 0.72, P = 0.41). Re-orientation time was faster in the methohexital arm (F(1,17) = 9.23, P = 0.007). Conclusion Ketamine inductions resulted in higher number of side-effects, higher subject dropout rates, and a longer reorientation time with respect to methohexital inductions. No significant difference in post-anesthesia recovery time was found between the ketamine and methohexital arms. Intolerability to ketamine affected a significant proportion of subjects, and suggests that ketamine should remain as an alternative or adjunctive agent for patients with high seizure thresholds. PMID:24755722

A Murine Model of Robotic Training to Evaluate Skeletal Muscle Recovery after Injury.

PubMed

Lai, Stefano; Panarese, Alessandro; Lawrence, Ross; Boninger, Michael L; Micera, Silvestro; Ambrosio, Fabrisia

2017-04-01

In vivo studies have suggested that motor exercise can improve muscle regeneration after injury. Nevertheless, preclinical investigations still lack reliable tools to monitor motor performance over time and to deliver optimal training protocols to maximize force recovery. Here, we evaluated the utility of a murine robotic platform (i) to detect early impairment and longitudinal recovery after acute skeletal muscle injury and (ii) to administer varying intensity training protocols to enhance forelimb motor performance. A custom-designed robotic platform was used to train mice to perform a forelimb retraction task. After an acute injury to bilateral biceps brachii muscles, animals performed a daily training protocol in the platform at high (HL) or low (LL) loading levels over the course of 3 wk. Control animals were not trained (NT). Motor performance was assessed by quantifying force, time, submovement count, and number of movement attempts to accomplish the task. Myofiber number and cross-sectional area at the injury site were quantified histologically. Two days after injury, significant differences in the time, submovement count, number of movement attempts, and exerted force were observed in all mice, as compared with baseline values. Interestingly, the recovery time of muscle force production differed significantly between intervention groups, with HL group showing a significantly accelerated recovery. Three weeks after injury, all groups showed motor performance comparable with baseline values. Accordingly, there were no differences in the number of myofibers or average cross-sectional area among groups after 3 wk. Our findings demonstrate the utility of our custom-designed robotic device for the quantitative assessment of skeletal muscle function in preclinical murine studies. Moreover, we demonstrate that this device may be used to apply varying levels of resistance longitudinally as a means manipulate physiological muscle responses.

Statistical analysis of the location of the Martian magnetic pileup boundary and bow shock and the influence of crustal magnetic fields

NASA Astrophysics Data System (ADS)

Edberg, N. J. T.; Lester, M.; Cowley, S. W. H.; Eriksson, A. I.

2008-08-01

We use the data set from the magnetometer and electron reflectometer instruments on board the Mars Global Surveyor spacecraft to show that the crustal magnetic fields of Mars affect the location of the magnetic pileup boundary (MPB) and bow shock (BS) globally. We search for crossings of the MPB and BS in the data that were observed over the first 16 months of the mission. To identify the influence of the crustal magnetic fields, all crossings are extrapolated to the terminator plane in order to remove the solar zenith angle (SZA) dependence, and to make it possible to compare crossings independently of location. The MPB crossings that were observed over regions on Mars, which contain strong crustal magnetic fields, are on average located further out than crossings observed over regions with weak crustal fields. This is shown in three separate longitude intervals. We also find that the dayside BS crossings observed over the southern hemisphere of Mars are on average located further out than the BS crossings observed over the northern hemisphere, possibly because of the influence of the crustal fields. We also study the magnetic field strength and its variation at the inside of the MPB and their dependence on the SZA and altitude. We find that the magnitude of the magnetic field in the MPB is closely linked to the altitude of the MPB, with the magnitude increasing as the MPB is observed closer to the planet.

Changing trends in the prevalence of blindness and visual impairment in a rural district of India: Systematic observations over a decade

PubMed Central

Khanna, Rohit C; Marmamula, Srinivas; Krishnaiah, Sannapaneni; Giridhar, Pyda; Chakrabarti, Subhabrata; Rao, Gullapalli N

2012-01-01

Context: Globally, limited data are available on changing trends of blindness from a single region. Aims: To report the changing trends in the prevalence of blindness, visual impairment (VI), and visual outcomes of cataract surgery in a rural district of Andhra Pradesh, India, over period of one decade. Settings and Design: Rural setting; cross-sectional study. Materials and Methods: Using a validated Rapid Assessment of Cataract Surgical Services (RACSS) method, population-based, cross-sectional survey was done in a rural district in the state of Andhra Pradesh, India. Two-stage sampling procedure was used to select participants ≥50 years of age. Further, a comparative analysis was done with participants ≥50 years from the previously concluded Andhra Pradesh Eye Disease Study (APEDS) study, who belonged to the same district. Statistical Analysis: Done using 11th version of Stata. Results: Using RACSS, 2160/2300 (93.9%) participants were examined as compared with the APEDS dataset (n=521). Age and sex adjusted prevalence of blindness in RACSS and APEDS was 8% (95% CI, 6.9–9.1%) and 11% (95% CI, 8.3–13.7%), while that of VI was 13.6% (95% CI, 12.2–15.1%) and 40.3% (95% CI, 36.1–44.5%), respectively. Cataract was the major cause of blindness in both the studies. There was a significant reduction in blindness following cataract surgery as observed through RACSS (17.3%; 95% CI, 13.5–21.8%) compared with APEDS (34%; 95% CI, 20.9–49.3%). Conclusion: There was a significant reduction in prevalence of blindness and VI in this rural district of India over a decade. PMID:22944766

Changing trends in the prevalence of blindness and visual impairment in a rural district of India: systematic observations over a decade.

PubMed

Khanna, Rohit C; Marmamula, Srinivas; Krishnaiah, Sannapaneni; Giridhar, Pyda; Chakrabarti, Subhabrata; Rao, Gullapalli N

2012-01-01

Context : Globally, limited data are available on changing trends of blindness from a single region. Aims : To report the changing trends in the prevalence of blindness, visual impairment (VI), and visual outcomes of cataract surgery in a rural district of Andhra Pradesh, India, over period of one decade. Settings and Design : Rural setting; cross-sectional study. Materials and Methods : Using a validated Rapid Assessment of Cataract Surgical Services (RACSS) method, population-based, cross-sectional survey was done in a rural district in the state of Andhra Pradesh, India. Two-stage sampling procedure was used to select participants ≥50 years of age. Further, a comparative analysis was done with participants ≥50 years from the previously concluded Andhra Pradesh Eye Disease Study (APEDS) study, who belonged to the same district. Statistical Analysis : Done using 11 th version of Stata. Results : Using RACSS, 2160/2300 (93.9%) participants were examined as compared with the APEDS dataset (n=521). Age and sex adjusted prevalence of blindness in RACSS and APEDS was 8% (95% CI, 6.9-9.1%) and 11% (95% CI, 8.3-13.7%), while that of VI was 13.6% (95% CI, 12.2-15.1%) and 40.3% (95% CI, 36.1-44.5%), respectively. Cataract was the major cause of blindness in both the studies. There was a significant reduction in blindness following cataract surgery as observed through RACSS (17.3%; 95% CI, 13.5-21.8%) compared with APEDS (34%; 95% CI, 20.9-49.3%). Conclusion : There was a significant reduction in prevalence of blindness and VI in this rural district of India over a decade.

Manipulating the fidelity of lower extremity visual feedback to identify obstacle negotiation strategies in immersive virtual reality.

PubMed

Kim, Aram; Zhou, Zixuan; Kretch, Kari S; Finley, James M

2017-07-01

The ability to successfully navigate obstacles in our environment requires integration of visual information about the environment with estimates of our body's state. Previous studies have used partial occlusion of the visual field to explore how information about the body and impending obstacles are integrated to mediate a successful clearance strategy. However, because these manipulations often remove information about both the body and obstacle, it remains to be seen how information about the lower extremities alone is utilized during obstacle crossing. Here, we used an immersive virtual reality (VR) interface to explore how visual feedback of the lower extremities influences obstacle crossing performance. Participants wore a head-mounted display while walking on treadmill and were instructed to step over obstacles in a virtual corridor in four different feedback trials. The trials involved: (1) No visual feedback of the lower extremities, (2) an endpoint-only model, (3) a link-segment model, and (4) a volumetric multi-segment model. We found that the volumetric model improved success rate, placed their trailing foot before crossing and leading foot after crossing more consistently, and placed their leading foot closer to the obstacle after crossing compared to no model. This knowledge is critical for the design of obstacle negotiation tasks in immersive virtual environments as it may provide information about the fidelity necessary to reproduce ecologically valid practice environments.

Meiotic gene-conversion rate and tract length variation in the human genome.

PubMed

Padhukasahasram, Badri; Rannala, Bruce

2013-02-27

Meiotic recombination occurs in the form of two different mechanisms called crossing-over and gene-conversion and both processes have an important role in shaping genetic variation in populations. Although variation in crossing-over rates has been studied extensively using sperm-typing experiments, pedigree studies and population genetic approaches, our knowledge of variation in gene-conversion parameters (ie, rates and mean tract lengths) remains far from complete. To explore variability in population gene-conversion rates and its relationship to crossing-over rate variation patterns, we have developed and validated using coalescent simulations a comprehensive Bayesian full-likelihood method that can jointly infer crossing-over and gene-conversion rates as well as tract lengths from population genomic data under general variable rate models with recombination hotspots. Here, we apply this new method to SNP data from multiple human populations and attempt to characterize for the first time the fine-scale variation in gene-conversion parameters along the human genome. We find that the estimated ratio of gene-conversion to crossing-over rates varies considerably across genomic regions as well as between populations. However, there is a great degree of uncertainty associated with such estimates. We also find substantial evidence for variation in the mean conversion tract length. The estimated tract lengths did not show any negative relationship with the local heterozygosity levels in our analysis.European Journal of Human Genetics advance online publication, 27 February 2013; doi:10.1038/ejhg.2013.30.

An Ultra-Wideband Cross-Correlation Radiometer for Mesoscopic Experiments

NASA Astrophysics Data System (ADS)

Toonen, Ryan; Haselby, Cyrus; Qin, Hua; Eriksson, Mark; Blick, Robert

2007-03-01

We have designed, built and tested a cross-correlation radiometer for detecting statistical order in the quantum fluctuations of mesoscopic experiments at sub-Kelvin temperatures. Our system utilizes a fully analog front-end--operating over the X- and Ku-bands (8 to 18 GHz)--for computing the cross-correlation function. Digital signal processing techniques are used to provide robustness against instrumentation drifts and offsets. The economized version of our instrument can measure, with sufficient correlation efficiency, noise signals having power levels as low as 10 fW. We show that, if desired, we can improve this performance by including cryogenic preamplifiers which boost the signal-to-noise ratio near the signal source. By adding a few extra components, we can measure both the real and imaginary parts of the cross-correlation function--improving the overall signal-to-noise ratio by a factor of sqrt[2]. We demonstrate the utility of our cross-correlator with noise power measurements from a quantum point contact.

Methodological issues in HIV-related social research in Nigeria.

PubMed

Erinosho, Olayiwola; Joseph, Richard; Isiugo-Abanihe, Uche; Dike, Nkem; Aderinto, Adeyinka A

2013-12-01

This paper is about methodological issues in a community-wide study in Nigeria on an infectious disease, namely HIV/AIDS. The study was designed to ascertain the risk factors that contribute to the spread of HIV/AIDS and how that can be tackled in order to bring about behavioural change. The research team believed at the onset that a study on the interplay between HIV/AIDS and sensitive issues like sexual mores and sexuality requires much more than a straightjacket social science method, such as simply doing a cross-section study and/or using interview schedule. This paper reviews the essence of cross-disciplinary approach; team building; as well as the use of a non-participatory observational approach in data collection. It also shows why ample consideration was given to ethical issues which are often glossed over in social research in developing countries. The lessons from the study underscore the methodological imperatives in social research that focus on sensitive issues in largely non-literate context like Nigeria. Although there are formidable challenges in community-based studies in largely non-literate societies, nevertheless they could easily be surmounted if there are ample time and resources to navigate the various sticking points.

Enhanced bioavailability of lycopene when consumed as cis-isomers from tangerine compared to red tomato juice, a randomized, cross-over clinical trial.

PubMed

Cooperstone, Jessica L; Ralston, Robin A; Riedl, Ken M; Haufe, Thomas C; Schweiggert, Ralf M; King, Samantha A; Timmers, Cynthia D; Francis, David M; Lesinski, Gregory B; Clinton, Steven K; Schwartz, Steven J

2015-04-01

Tangerine tomatoes (Solanum lycopersicum) are rich in tetra-cis-lycopene resulting from natural variation in carotenoid isomerase. Our objective was to compare the bioavailability of lycopene from tangerine to red tomato juice, and elucidate physical deposition forms of these isomers in tomatoes by light and electron microscopy. Following a randomized cross-over design, subjects (n = 11, 6 M/5 F) consumed two meals delivering 10 mg lycopene from tangerine (94% cis) or red tomato juice (10% cis). Blood was sampled over 12 h and triglyceride-rich lipoprotein fractions of plasma were isolated and analyzed using HPLC-DAD-MS/MS. Lycopene was crystalline in red tomato chromoplasts and globular in tangerine tomatoes. With tangerine tomato juice we observed a marked 8.5-fold increase in lycopene bioavailability compared to red tomato juice (p < 0.001). Fractional absorption was 47.70 ± 8.81% from tangerine and 4.98 ± 1.92% from red tomato juices. Large heterogeneity was observed among subjects. Lycopene is markedly more bioavailable from tangerine than from red tomato juice, consistent with a predominance of cis-lycopene isomers and presence in chromoplasts in a lipid dissolved globular state. These results justify using tangerine tomatoes as a lycopene source in studies examining the potential health benefits of lycopene-rich foods. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Comparative Evaluation of Stress Distribution in Experimentally Designed Nickel-titanium Rotary Files with Varying Cross Sections: A Finite Element Analysis.

PubMed

Basheer Ahamed, Shadir Bughari; Vanajassun, Purushothaman Pranav; Rajkumar, Kothandaraman; Mahalaxmi, Sekar

2018-04-01

Single cross-sectional nickel-titanium (NiTi) rotary instruments during continuous rotations are subjected to constant and variable stresses depending on the canal anatomy. This study was intended to create 2 new experimental, theoretic single-file designs with combinations of triple U (TU), triangle (TR), and convex triangle (CT) cross sections and to compare their bending stresses in simulated root canals with a single cross-sectional instrument using finite element analysis. A 3-dimensional model of the simulated root canal with 45° curvature and NiTi files with 5 cross-sectional designs were created using Pro/ENGINEER Wildfire 4.0 software (PTC Inc, Needham, MA) and ANSYS software (version 17; ANSYS, Inc, Canonsburg, PA) for finite element analysis. The NiTi files of 3 groups had single cross-sectional shapes of CT, TR, and TU designs, and 2 experimental groups had a CT, TR, and TU (CTU) design and a TU, TR, and CT (UTC) design. The file was rotated in simulated root canals to analyze the bending stress, and the von Mises stress value for every file was recorded in MPa. Statistical analysis was performed using the Kruskal-Wallis test and the Bonferroni-adjusted Mann-Whitney test for multiple pair-wise comparison with a P value <.05 (95 %). The maximum bending stress of the rotary file was observed in the apical third of the CT design, whereas comparatively less stress was recorded in the CTU design. The TU and TR designs showed a similar stress pattern at the curvature, whereas the UTC design showed greater stress in the apical and middle thirds of the file in curved canals. All the file designs showed a statistically significant difference. The CTU designed instruments showed the least bending stress on a 45° angulated simulated root canal when compared with all the other tested designs. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Acceptability of different oral formulations in infants and preschool children

PubMed Central

van Riet-Nales, Diana A; de Neef, Barbara J; Schobben, Alfred F A M; Ferreira, José A; Egberts, Toine C G; Rademaker, Catharine M A

2013-01-01

Objective Liquid medicines are easy to swallow. However, they may have disadvantages, such as a bad taste or refrigerated storage conditions. These disadvantages may be avoided by the use of oral solid medicines, such as powders or tablets. The aim of this study was to investigate the acceptability of and preference among four oral formulations in domiciliary infants and preschool children in The Netherlands. Methods Parents administered four oral placebo dosage forms that were aimed at a neutral taste, at home, to their child (1–4 years of age) twice on one day following a randomised cross-over design: small (4 mm) tablet, powder, suspension and syrup. They were asked to report the child's acceptability by a score on a 10 cm visual analogue scale (VAS score) and by the result of the intake. At the end of the study, they were asked to report the preference of the child and themselves. Results 183 children were included and 148 children were evaluated. The data revealed a period/cross-over effect. The estimate of the mean VAS score was significantly higher for the tablet than for the suspension (tablet 9.39/9.01; powder 8.84/8.20, suspension 8.26/7.90, syrup 8.35/8.19; data day 1/all days). The estimate of the mean number of intakes fully swallowed was significantly higher for the tablet than for the other formulations (all p values <0.05). Children and parents preferred the tablet and syrup over the suspension and the suspension over the powder (all p values <0.05). Conclusions All formulations were well accepted. The tablets were the best accepted formulation; the tablets and syrup the most preferred. Trial Registration number ISRCTN63138435. PMID:23853004

Stochastic resonance training reduces musculoskeletal symptoms in metal manufacturing workers: a controlled preventive intervention study.

PubMed

Burger, Christian; Schade, Volker; Lindner, Christina; Radlinger, Lorenz; Elfering, Achim

2012-01-01

This study examined the effects of stochastic resonance whole-body vibration training on work-related musculoskeletal symptoms and accidents. Participants were white and blue-collar employees of a Swiss metal manufacturer (N=38), and participation was voluntary. The study was designed as a switching-replications longitudinal trial with randomized group allocation. The randomized controlled cross-over design consisted of two groups each given four weeks of exercise and no intervention during a second four-week period. Outcome was measured on a daily basis with questionnaires. Three components constituted musculoskeletal symptoms: musculoskeletal pain, related function limitations and musculoskeletal well-being. Accidents were assessed by ratings for balance and daily near-accidents. For statistical analysis, a mixed model was calculated. At the end of the training period musculoskeletal pain and related function limitation were significantly reduced, whereas musculoskeletal well-being had significantly increased. For function limitation and musculoskeletal well-being, change over time was linear. There was no effect on balance or near-accidents. Stochastic resonance whole-body vibration was found to be effective in the prevention of work-related musculoskeletal symptoms. It is well suited for the use in a work environment since it requires very little effort in terms of infrastructure, time and investment from participants.

A methodology using in-chair movements as an objective measure of discomfort for the purpose of statistically distinguishing between similar seat surfaces.

PubMed

Cascioli, Vincenzo; Liu, Zhuofu; Heusch, Andrew; McCarthy, Peter W

2016-05-01

This study presents a method for objectively measuring in-chair movement (ICM) that shows correlation with subjective ratings of comfort and discomfort. Employing a cross-over controlled, single blind design, healthy young subjects (n = 21) sat for 18 min on each of the following surfaces: contoured foam, straight foam and wood. Force sensitive resistors attached to the sitting interface measured the relative movements of the subjects during sitting. The purpose of this study was to determine whether ICM could statistically distinguish between each seat material, including two with subtle design differences. In addition, this study investigated methodological considerations, in particular appropriate threshold selection and sitting duration, when analysing objective movement data. ICM appears to be able to statistically distinguish between similar foam surfaces, as long as appropriate ICM thresholds and sufficient sitting durations are present. A relationship between greater ICM and increased discomfort, and lesser ICM and increased comfort was also found. Copyright © 2016. Published by Elsevier Ltd.

Development of Improved Design and 3D Printing Manufacture of Cross-Flow Fan Rotor

DTIC Science & Technology

2016-06-01

the design study, each solver run was monitored. Plotting the value of the mass flows, as well as the torque on the rotor blades , allowed a simple...DISTRIBUTION CODE A 13. ABSTRACT (maximum 200 words) This study determined the optimum blade stagger angle for a cross-flow fan rotor and evaluated the...parametric study determined optimum blade stagger angle using thrust, power, and thrust-to-power ratio as desired output variables. A MarkForged Mark One 3D

Overcoming ecologic bias using the two-phase study design.

PubMed

Wakefield, Jon; Haneuse, Sebastien J-P A

2008-04-15

Ecologic (aggregate) data are widely available and widely utilized in epidemiologic studies. However, ecologic bias, which arises because aggregate data cannot characterize within-group variability in exposure and confounder variables, can only be removed by supplementing ecologic data with individual-level data. Here the authors describe the two-phase study design as a framework for achieving this objective. In phase 1, outcomes are stratified by any combination of area, confounders, and error-prone (or discretized) versions of exposures of interest. Phase 2 data, sampled within each phase 1 stratum, provide accurate measures of exposure and possibly of additional confounders. The phase 1 aggregate-level data provide a high level of statistical power and a cross-classification by which individuals may be efficiently sampled in phase 2. The phase 2 individual-level data then provide a control for ecologic bias by characterizing the within-area variability in exposures and confounders. In this paper, the authors illustrate the two-phase study design by estimating the association between infant mortality and birth weight in several regions of North Carolina for 2000-2004, controlling for gender and race. This example shows that the two-phase design removes ecologic bias and produces gains in efficiency over the use of case-control data alone. The authors discuss the advantages and disadvantages of the approach.

Exploring Structural Dynamics within and between Sensory and Intellectual Functioning in Old and Very Old Age: Longitudinal Evidence from the Berlin Aging Study

ERIC Educational Resources Information Center

Ghisletta, Paolo; Lindenberger, Ulman

2005-01-01

Cross-sectional and longitudinal analyses of age-heterogeneous samples have revealed correlational links between and within intellectual, sensory, and sensorimotor domains. Due to basic limitations of cross-sectional designs and a reluctance to disentangle antecedent-consequent relations in longitudinal designs, the functional significance and…

Comparative evaluation of stress levels before, during, and after periodontal surgical procedures with and without nitrous oxide-oxygen inhalation sedation.

PubMed

Sandhu, Gurkirat; Khinda, Paramjit Kaur; Gill, Amarjit Singh; Singh Khinda, Vineet Inder; Baghi, Kamal; Chahal, Gurparkash Singh

2017-01-01

Periodontal surgical procedures produce varying degree of stress in all patients. Nitrous oxide-oxygen inhalation sedation is very effective for adult patients with mild-to-moderate anxiety due to dental procedures and needle phobia. The present study was designed to perform periodontal surgical procedures under nitrous oxide-oxygen inhalation sedation and assess whether this technique actually reduces stress physiologically, in comparison to local anesthesia alone (LA) during lengthy periodontal surgical procedures. This was a randomized, split-mouth, cross-over study. A total of 16 patients were selected for this randomized, split-mouth, cross-over study. One surgical session (SS) was performed under local anesthesia aided by nitrous oxide-oxygen inhalation sedation, and the other SS was performed on the contralateral quadrant under LA. For each session, blood samples to measure and evaluate serum cortisol levels were obtained, and vital parameters including blood pressure, heart rate, respiratory rate, and arterial blood oxygen saturation were monitored before, during, and after periodontal surgical procedures. Paired t -test and repeated measure ANOVA. The findings of the present study revealed a statistically significant decrease in serum cortisol levels, blood pressure and pulse rate and a statistically significant increase in respiratory rate and arterial blood oxygen saturation during periodontal surgical procedures under nitrous oxide inhalation sedation. Nitrous oxide-oxygen inhalation sedation for periodontal surgical procedures is capable of reducing stress physiologically, in comparison to LA during lengthy periodontal surgical procedures.

Immediate acid-suppressing effects of ranitidine hydrochloride and rabeprazole sodium following initial administration and reintroduction: A randomized, cross-over study using wireless pH monitoring capsules.

PubMed

Ono, Shouko; Kato, Mototsugu; Ono, Yuji; Imai, Aki; Yoshida, Takeshi; Shimizu, Yuichi; Asaka, Masahiro

2009-04-01

Histamine 2 receptor antagonists and proton-pump inhibitors, drugs that are widely used for the treatment of acid-related diseases, have different clinical characteristics. The objective of this study was to compare the acid-suppressing effects of ranitidine hydrochloride and those of rabeprazole sodium at the first administration and re-administration after withdrawal. The study was designed as an open-label, randomized, two-way cross-over trial. Seven Helicobacter pylori-negative healthy volunteers were enrolled in this study. Ranitidine hydrochloride (300 mg/day) or rabeprazole sodium (20 mg/day) was administered from days 1 to 7 and from days 11 to 13. The percentage of time with gastric pH < 4 and the median gastric pH were evaluated for 15 consecutive days by a Bravo capsule fixed to the stomach. On day 1, there was no significant difference between the acid-suppressing effects of the two drugs (ranitidine vs rabeprazole: not significant). Although rabeprazole sodium maintained a potent and stable effect from days 2 to 7 (ranitidine vs rabeprazole: P < 0.05), the effect of ranitidine hydrochloride was attenuated after day 4. In addition, the effect of ranitidine hydrochloride at re-administration was attenuated (days 11, 12, and 13 vs pre-administration: not significant). In view of our observations, we expect symptoms associated with gastric acidity to be more adequately controlled with rabeprazole sodium in the short term when compared to ranitidine hydrochloride.

An intelligent monitoring and management system for cross-enterprise biomedical data sharing platform

NASA Astrophysics Data System (ADS)

Wang, Tusheng; Yang, Yuanyuan; Zhang, Jianguo

2013-03-01

In order to enable multiple disciplines of medical researchers, clinical physicians and biomedical engineers working together in a secured, efficient, and transparent cooperative environment, we had designed an e-Science platform for biomedical imaging research and application cross multiple academic institutions and hospitals in Shanghai by using grid-based or cloud-based distributed architecture and presented this work in SPIE Medical Imaging conference held in San Diego in 2012. However, when the platform integrates more and more nodes over different networks, the first challenge is that how to monitor and maintain all the hosts and services operating cross multiple academic institutions and hospitals in the e-Science platform, such as DICOM and Web based image communication services, messaging services and XDS ITI transaction services. In this presentation, we presented a system design and implementation of intelligent monitoring and management which can collect system resource status of every node in real time, alert when node or service failure occurs, and can finally improve the robustness, reliability and service continuity of this e-Science platform.

The Collaborative Cross at Oak Ridge National Laboratory: developing a powerful resource for systems genetics

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

Chesler, Elissa J; Branstetter, Lisa R; Churchill, Gary A

2008-01-01

Complex traits and disease co-morbidity in humans and in model organisms are the result of naturally occurring polymorphisms that interact with each other and with the environment. To ensure the availability of the resources needed to investigate biomolecular networks and ultimately systems level phenotypes, we have initiated breeding of a new genetic reference population of mice, the Collaborative Cross. This population has been designed to optimally support systems genetics analysis. Its novel and important features include high levels of genetic diversity, a large population size to ensure sufficient power in high-dimensional studies, and high mapping precision through accumulation of independentmore » recombination events. Implementation of the Collaborative Cross has been in progress at the Oak Ridge National Laboratory (ORNL) since May 2005. This is achieved through a software assisted breeding program with fully traceable lineages, performed in a uniform environment. Currently, there are 650 lines in production with almost 200 lines over seven generations of inbreeding. Retired breeders enter a high-throughput phenotyping protocol and DNA samples are banked for analysis of recombination history, allele loss, and population structure. Herein we present a progress report of the Collaborative Cross breeding program at ORNL and a description of the kinds of investigations that this resource will support.« less

Development of a Composite Measure of State-Level Malpractice Environment

PubMed Central

Chung, Jeanette W; Sohn, Min-Woong; Merkow, Ryan P; Oh, Elissa H; Minami, Christina; Black, Bernard S; Bilimoria, Karl Y

2014-01-01

Objective To develop a composite measure of state-level malpractice environment. Data Sources Public use data from the National Practitioner Data Bank, Medical Liability Monitor, the National Conference of State Legislatures, and the American Bar Association. Study Design Principal component analysis of state-level indicators (paid claims rate, malpractice premiums, lawyers per capita, average award size, and malpractice laws), with indirect validation of the composite using receiver-operating characteristic curves to determine how accurately the composite could identify states with high-tort activity and costs. Principal Findings A single composite accounted for over 73 percent of total variance in the seven indicators and demonstrated reasonable criterion validity. Conclusion An empirical composite measure of state-level malpractice risk may offer advantages over single indicators in measuring overall risk and may facilitate cross-state comparisons of malpractice environments. PMID:24117397

Spelling and Reading Development: The Effect of Teaching Children Multiple Levels of Representation in Their Orthography

ERIC Educational Resources Information Center

Devonshire, Victoria; Morris, Paul; Fluck, Michael

2013-01-01

A novel intervention was developed to teach reading and spelling literacy to 5 to 7 year-old students using explicit instruction of morphology, etymology, phonology, and form rules. We examined the effects of the intervention compared to a phonics-based condition using a cross-over design with a baseline measure. One hundred and twenty children…

Implementation of cross correlation for energy discrimination on the time-of-flight spectrometer CORELLI.

PubMed

Ye, Feng; Liu, Yaohua; Whitfield, Ross; Osborn, Ray; Rosenkranz, Stephan

2018-04-01

The CORELLI instrument at Oak Ridge National Laboratory is a statistical chopper spectrometer designed and optimized to probe complex disorder in crystalline materials through diffuse scattering experiments. On CORELLI, the high efficiency of white-beam Laue diffraction combined with elastic discrimination have enabled an unprecedented data collection rate to obtain both the total and the elastic-only scattering over a large volume of reciprocal space from a single measurement. To achieve this, CORELLI is equipped with a statistical chopper to modulate the incoming neutron beam quasi-randomly, and then the cross-correlation method is applied to reconstruct the elastic component from the scattering data. Details of the implementation of the cross-correlation method on CORELLI are given and its performance is discussed.

Implementation of cross correlation for energy discrimination on the time-of-flight spectrometer CORELLI

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

Ye, Feng; Liu, Yaohua; Whitfield, Ross

The CORELLI instrument at Oak Ridge National Laboratory is a statistical chopper spectrometer designed and optimized to probe complex disorder in crystalline materials through diffuse scattering experiments. On CORELLI, the high efficiency of white-beam Laue diffraction combined with elastic discrimination have enabled an unprecedented data collection rate to obtain both the total and the elastic-only scattering over a large volume of reciprocal space from a single measurement. To achieve this, CORELLI is equipped with a statistical chopper to modulate the incoming neutron beam quasi-randomly, and then the cross-correlation method is applied to reconstruct the elastic component from the scattering data.more » Lastly, details of the implementation of the cross-correlation method on CORELLI are given and its performance is discussed.« less

Implementation of cross correlation for energy discrimination on the time-of-flight spectrometer CORELLI

DOE PAGES

Ye, Feng; Liu, Yaohua; Whitfield, Ross; ...

2018-03-26

The CORELLI instrument at Oak Ridge National Laboratory is a statistical chopper spectrometer designed and optimized to probe complex disorder in crystalline materials through diffuse scattering experiments. On CORELLI, the high efficiency of white-beam Laue diffraction combined with elastic discrimination have enabled an unprecedented data collection rate to obtain both the total and the elastic-only scattering over a large volume of reciprocal space from a single measurement. To achieve this, CORELLI is equipped with a statistical chopper to modulate the incoming neutron beam quasi-randomly, and then the cross-correlation method is applied to reconstruct the elastic component from the scattering data.more » Lastly, details of the implementation of the cross-correlation method on CORELLI are given and its performance is discussed.« less

Computer classes and games in virtual reality environment to reduce loneliness among students of an elderly reference center: Study protocol for a randomised cross-over design.

PubMed

Antunes, Thaiany Pedrozo Campos; Oliveira, Acary Souza Bulle de; Crocetta, Tania Brusque; Antão, Jennifer Yohanna Ferreira de Lima; Barbosa, Renata Thais de Almeida; Guarnieri, Regiani; Massetti, Thais; Monteiro, Carlos Bandeira de Mello; Abreu, Luiz Carlos de

2017-03-01

Physical and mental changes associated with aging commonly lead to a decrease in communication capacity, reducing social interactions and increasing loneliness. Computer classes for older adults make significant contributions to social and cognitive aspects of aging. Games in a virtual reality (VR) environment stimulate the practice of communicative and cognitive skills and might also bring benefits to older adults. Furthermore, it might help to initiate their contact to the modern technology. The purpose of this study protocol is to evaluate the effects of practicing VR games during computer classes on the level of loneliness of students of an elderly reference center. This study will be a prospective longitudinal study with a randomised cross-over design, with subjects aged 50 years and older, of both genders, spontaneously enrolled in computer classes for beginners. Data collection will be done in 3 moments: moment 0 (T0) - at baseline; moment 1 (T1) - after 8 typical computer classes; and moment 2 (T2) - after 8 computer classes which include 15 minutes for practicing games in VR environment. A characterization questionnaire, the short version of the Short Social and Emotional Loneliness Scale for Adults (SELSA-S) and 3 games with VR (Random, MoviLetrando, and Reaction Time) will be used. For the intervention phase 4 other games will be used: Coincident Timing, Motor Skill Analyser, Labyrinth, and Fitts. The statistical analysis will compare the evolution in loneliness perception, performance, and reaction time during the practice of the games between the 3 moments of data collection. Performance and reaction time during the practice of the games will also be correlated to the loneliness perception. The protocol is approved by the host institution's ethics committee under the number 52305215.3.0000.0082. Results will be disseminated via peer-reviewed journal articles and conferences. This clinical trial is registered at ClinicalTrials.gov identifier: NCT02798081.

Effect of Cross Sectional Geometry on PDMS Micro Peristaltic Pump Performance: Comparison of SU-8 Replica Molding vs. Micro Injection Molding

PubMed Central

Graf, Neil J.

2013-01-01

Two different fabrication methods were employed to fabricate micropumps with different cross-sectional channel geometries. The first was to fabricate rectangular cross-sectional microchannel geometries using the well known fabrication method of replica molding (REM).1 The second, and far less utilized fabrication technique, was to create microchannel molds using an in-house fabricated handheld micro injection molding apparatus. The injection mold apparatus was designed for use with elastomeric room temperature vulcanization (RTV) polymers, as opposed to most other injection molding machines, which are designed for use with thermoplastic polymers. The injection mold’s bottom plate was used as a microchannel molding template. The molding template was created by threading a small-diameter wire (150 μm or less) through the injection mold’s bottom plate, with subsequent adhesion and smoothing of a thin piece of aluminum foil over the wire-raised injection mold template. When molded against, the template produced a rounded/Gaussian-shaped PDMS microchannel. The design of the injection mold will be presented, along with a direct comparison for micropump performance metrics such as flow rate, valving characteristics, and maximum backpressures attainable for each of the respective micropump channel geometries. PMID:23917263

Direct Reactions at the Facility for Experiments on Nuclear Reactions in Stars (FENRIS)

NASA Astrophysics Data System (ADS)

Longland, Richard; Kelley, John; Marshall, Caleb; Portillo, Federico; Setoodehnia, Kiana

2017-09-01

Nuclear cross sections are a key ingredient in stellar models designed to understand how stars evolve. Determining these cross sections, therefore, is critical for obtaining reliable predictions from stellar models. While many charged-particle reaction cross sections can be measured in the laboratory, the Coulomb barrier means that they cannot always be measured at the low energies relevant to astrophysics. In other cases, radioactive targets make the measurements unfeasible. Radioactive ion beam experiments in inverse kinematics are one solution, but low beam intensities mean that cross sections plague these attempts further. Direct measurements, particularly particle transfer experiments, are one tool in our inventory that provides us with the necessary information to infer reaction cross sections at stellar energies. I will present an overview of one facility: the Facility for Experiments on Nuclear Reactions in Stars (FENRIS), which is dedicated to performing particle transfer measurements for astrophysical cross sections. Over the past few years, FENRIS has been fully upgraded and characterized. I will show highlights of our upgrade activities and current capabilities. I will also highlight our recent experimental results and discuss current upgrade efforts.

Genomic Dissection of Leaf Angle in Maize (Zea mays L.) Using a Four-Way Cross Mapping Population.

PubMed

Ding, Junqiang; Zhang, Luyan; Chen, Jiafa; Li, Xiantang; Li, Yongming; Cheng, Hongliang; Huang, Rongrong; Zhou, Bo; Li, Zhimin; Wang, Jiankang; Wu, Jianyu

2015-01-01

Increasing grain yield by the selection for optimal plant architecture has been the key focus in modern maize breeding. As a result, leaf angle, an important determinant of plant architecture, has been significantly improved to adapt to the ever-increasing plant density in maize production over the past several decades. To extend our understanding on the genetic mechanisms of leaf angle in maize, we developed the first four-way cross mapping population, consisting of 277 lines derived from four maize inbred lines with varied leaf angles. The four-way cross mapping population together with the four parental lines were evaluated for leaf angle in two environments. In this study, we reported linkage maps built in the population and quantitative trait loci (QTL) on leaf angle detected by inclusive composite interval mapping (ICIM). ICIM applies a two-step strategy to effectively separate the cofactor selection from the interval mapping, which controls the background additive and dominant effects at the same time. A total of 14 leaf angle QTL were identified, four of which were further validated in near-isogenic lines (NILs). Seven of the 14 leaf angle QTL were found to overlap with the published leaf angle QTL or genes, and the remaining QTL were unique to the four-way population. This study represents the first example of QTL mapping using a four-way cross population in maize, and demonstrates that the use of specially designed four-way cross is effective in uncovering the basis of complex and polygenetic trait like leaf angle in maize.

Genomic Dissection of Leaf Angle in Maize (Zea mays L.) Using a Four-Way Cross Mapping Population

PubMed Central

Li, Xiantang; Li, Yongming; Cheng, Hongliang; Huang, Rongrong; Zhou, Bo; Li, Zhimin; Wang, Jiankang; Wu, Jianyu

2015-01-01

Increasing grain yield by the selection for optimal plant architecture has been the key focus in modern maize breeding. As a result, leaf angle, an important determinant of plant architecture, has been significantly improved to adapt to the ever-increasing plant density in maize production over the past several decades. To extend our understanding on the genetic mechanisms of leaf angle in maize, we developed the first four-way cross mapping population, consisting of 277 lines derived from four maize inbred lines with varied leaf angles. The four-way cross mapping population together with the four parental lines were evaluated for leaf angle in two environments. In this study, we reported linkage maps built in the population and quantitative trait loci (QTL) on leaf angle detected by inclusive composite interval mapping (ICIM). ICIM applies a two-step strategy to effectively separate the cofactor selection from the interval mapping, which controls the background additive and dominant effects at the same time. A total of 14 leaf angle QTL were identified, four of which were further validated in near-isogenic lines (NILs). Seven of the 14 leaf angle QTL were found to overlap with the published leaf angle QTL or genes, and the remaining QTL were unique to the four-way population. This study represents the first example of QTL mapping using a four-way cross population in maize, and demonstrates that the use of specially designed four-way cross is effective in uncovering the basis of complex and polygenetic trait like leaf angle in maize. PMID:26509792

Effects of Crossed Brassiere Straps on Pain, Range of Motion, and Electromyographic Activity of Scapular Upward Rotators in Women With Scapular Downward Rotation Syndrome.

PubMed

Kang, Min-Hyeok; Choi, Ji-Young; Oh, Jae-seop

2015-12-01

Scapular downward rotation syndrome manifests as an abnormally downward-rotated scapula at rest or with arm motion and typically results in neck and shoulder pain. The brassiere strap has been suggested as a possible contributing factor to scapula downward rotation and pain in the upper trapezius because of increased downward rotational force on the lateral aspect of the scapula. No study, however, has examined the influences of a modified brassiere strap on pain in and the function of the scapular muscles. To examine the effects of crossed brassiere straps on the pressure pain threshold (PPT) of the upper trapezius, neck rotation range of motion (ROM), and electromyographic activity of the scapular upward rotators in females with scapular downward rotation syndrome. Cross-over design. Laboratory. In total, 15 female subjects with scapular downward rotation syndrome were recruited at hospitals and a local university. All participants performed neck rotation and humeral elevation under 2 different conditions: parallel and crossed brassiere straps. The PPT of the upper trapezius was measured using an analog algometer, whereas neck rotation ROM was quantified with a 3-dimensional ultrasonic motion analysis system. The electromyographic activities of the upper trapezius, serratus anterior, and lower trapezius during humeral elevation were assessed with a surface electromyography system. Outcome measures were assessed under parallel and crossed brassiere strap conditions, and differences in outcomes between the conditions were analyzed using a paired t-test. The PPT and neck rotation ROM were increased when the subject was wearing the brassiere with crossed versus parallel straps (P < .001). Greater electromyographic activities of the serratus anterior, lower trapezius, and lesser upper trapezius muscles during humeral elevation were found under the crossed strap condition than the parallel strap condition (P < .05). These findings provide useful information for clinicians when designing management programs to decrease pain and improve biomechanical function for females with scapular downward rotation syndrome. Copyright © 2015 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Biophysical characterization of a de novo elastin

NASA Astrophysics Data System (ADS)

Greenland, Kelly Nicole

Natural human elastin is found in tissue such as the lungs, arteries, and skin. This protein is formed at birth with no mechanism present to repair or supplement the initial quantity formed. As a result, the functionality and durability of elastin's elasticity is critically important. To date, the mechanics of this ability to stretch and recoil is not fully understood. This study utilizes de novo protein design to create a small library of simplistic versions of elastin-like proteins, demonstrate the elastin-like proteins, maintain elastin's functionality, and inquire into its structure using solution nuclear magnetic resonance (NMR). Elastin is formed from cross-linked tropoelastin. Therefore, the first generation of designed proteins consisted of one protein that utilized homogony of interspecies tropoelastin by using three common domains, two hydrophobic and one cross-linking domains. Basic modifications were made to open the hydrophobic region and also to make the protein easier to purify and characterize. The designed protein maintained its functionality, self-aggregating as the temperature increased. Uniquely, the protein remained self-aggregated as the temperature returned below the critical transition temperature. Self-aggregation was additionally induced by increasing salt concentrations and by modifying the pH. The protein appeared to have little secondary structure when studied with solution NMR. These results fueled a second generation of designed elastin-like proteins. This generation contained variations designed to study the cross-linking domain, one specific hydrophobic domain, and the effect of the length of the elastin-like protein. The cross-linking domain in one variation has been significantly modified while the flanking hydrophobic domains have remained unchanged. This characterization of this protein will answer questions regarding the specificity of the homologous nature of the cross-linking domain of tropoelastin across species. A second protein has additional hydrophobic domains flanking the originally designed elastin-like protein. The characterization of this protein will answer questions regarding the functionality of longer or more hydrophobic elastin-like proteins. The final variation designed is one hydrophobic domain and the new cross-linking domain repeating several times. The characterization of this protein will answer questions regarding the specific hydrophobic domain and its functionality.

Depressive symptoms in elderly participants of an open university for elderly

PubMed Central

Batistoni, Samila Sathler Tavares; Ordonez, Tiago Nascimento; da Silva, Thaís Bento Lima; do Nascimento, Priscila Pascarelli Pedrico; Kissaki, Priscilla Tiemi; Cachioni, Meire

2011-01-01

Although the prevalence of depressive disorders among the elderly is lower than among the younger population, the presence of significant symptoms of depression is common in this group. Studies report that participation in social, educational and leisure activities is related to fewer depressive symptoms in this population. Objective The aim of this study was to examine the prevalence of depression among elderly participants of an Open University for the Third Age, in terms of the time studying. Methods The study had a cross-sectional design and the participation of 95.2% (n=184) of total enrollers in the first half of 2010 on the activities of the Third Age Open University’s School of Arts, Sciences and Humanities of the University of São Paulo. All participants answered a socio-demographic questionnaire and the Geriatric Depression Scale (GDS-15). Results An association between studying time of over one semester at the University of the Third Age and a lower rate of depressive symptoms, was observed. Conclusion Study time of over one semester was associated with less depressive symptoms, acting as a possible protective factor against depression. PMID:29213728

Cross-Validation of easyCBM Reading Cut Scores in Washington: 2009-2010. Technical Report #1109

ERIC Educational Resources Information Center

Irvin, P. Shawn; Park, Bitnara Jasmine; Anderson, Daniel; Alonzo, Julie; Tindal, Gerald

2011-01-01

This technical report presents results from a cross-validation study designed to identify optimal cut scores when using easyCBM[R] reading tests in Washington state. The cross-validation study analyzes data from the 2009-2010 academic year for easyCBM[R] reading measures. A sample of approximately 900 students per grade, randomly split into two…

Occupational Stress and Management Strategies of Secondary School Principals in Cross River State, Nigeria

ERIC Educational Resources Information Center

Anyanwu, Joy; Ezenwaji, Ifeyinwa; Okenjom, Godian; Enyi, Chinwe

2015-01-01

The study aimed at finding out sources and symptoms of occupational stress and management strategies of principals in secondary schools in Cross River State, Nigeria. Descriptive survey research design was adopted for the study with a population of 420 principals (304 males and 116 females) in secondary schools in Cross River State, Nigeria. Three…

Coil End Parts Development Using BEND and Design for MQXF by LARP

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

Yu, Miao; Ambrosio, G.; Bermudez, S. Izquierdo

2016-09-06

End parts are critical components for saddle-shaped coils. They have a structural function where the cables are deformed in order to cross over the magnet aperture. Based on the previous design of the US LARP program for 90 mm aperture quadrupoles (TQ/LQ) and 120 mm aperture quadrupoles (HQ/LHQ) using BEND, the coil ends of the low-β quadruples (MQXF) for the HiLumi LHC upgrade were developed. This paper shows the design of the MQXF coil ends, the analysis of the coil ends during the coil fabrication, the autopsy analysis of the coil ends and the feedback to BEND parameters.

The early maximum likelihood estimation model of audiovisual integration in speech perception.

PubMed

Andersen, Tobias S

2015-05-01

Speech perception is facilitated by seeing the articulatory mouth movements of the talker. This is due to perceptual audiovisual integration, which also causes the McGurk-MacDonald illusion, and for which a comprehensive computational account is still lacking. Decades of research have largely focused on the fuzzy logical model of perception (FLMP), which provides excellent fits to experimental observations but also has been criticized for being too flexible, post hoc and difficult to interpret. The current study introduces the early maximum likelihood estimation (MLE) model of audiovisual integration to speech perception along with three model variations. In early MLE, integration is based on a continuous internal representation before categorization, which can make the model more parsimonious by imposing constraints that reflect experimental designs. The study also shows that cross-validation can evaluate models of audiovisual integration based on typical data sets taking both goodness-of-fit and model flexibility into account. All models were tested on a published data set previously used for testing the FLMP. Cross-validation favored the early MLE while more conventional error measures favored more complex models. This difference between conventional error measures and cross-validation was found to be indicative of over-fitting in more complex models such as the FLMP.

Multi-functional polyelectrolyte multilayer films: combining mechanical resistance, biodegradability and bioactivity

PubMed Central

Schneider, Aurore; Vodouhê, Constant; Richert, Ludovic; Francius, Gregory; Le Guen, Erell; Schaaf, Pierre; Voegel, Jean-Claude; Frisch, Benoît; Picart, Catherine

2008-01-01

Cross-linked polyelectrolyte multilayer films (CL PEM) have an increased rigidity and are mechanically more resistant than native (e.g. uncrosslinked) films. However, they are still biodegradable, which make them interesting candidates for biomedical applications. In this study, CL PEM films have been explored for their multifunctional properties as i) mechanically resistant ii) biodegradable and iii) bioactive films. Toward this end, we investigated drug loading into CL chitosan/hyaluronan (CHI/HA) and poly(L-lysine)/hyaluronan (PLL/HA) films by simple diffusion of the drugs. Sodium diclofenac and paclitaxel were chosen as model drugs and were successfully loaded into the films. The effect of varying the number of layers in the (CHI/HA) films as well as the cross-linker concentration on diclofenac loading were studied. Diclofenac was released from the film in about ten hours. Paclitaxel was also found to diffuse within CL films. Its activity was maintained after loading in the CL films and cellular viability could be reduced by about 55% over three days. Such simple approach may be applied to other types of cross-linked films and to other drugs. These results prove that it is possible to design multifunctional multilayer films that combine mechanical resistance, biodegradability and bioactivity properties into a single PEM architecture. PMID:17206799

Who Gets Designated a Terrorist and Why?

ERIC Educational Resources Information Center

Beck, Colin J.; Miner, Emily

2013-01-01

This study examines formal terrorism designations by governments through the lens of organization studies research on categorization processes. It is argued that designations hinge on markers from the organizational profile of a militant group. Using cross-sectional data on militant organizations and designations by the United States, the United…

Data on a single oral dose of camu camu (Myrciaria dubia) pericarp extract on flow-mediated vasodilation and blood pressure in young adult humans.

PubMed

Miyashita, Tadayoshi; Koizumi, Ryosuke; Myoda, Takao; Sagane, Yoshimasa; Niwa, Koichi; Watanabe, Toshihiro; Minami, Kazuhiro

2018-02-01

This data article describes the flow-mediated vasodilation (FMD) responses, represented by changes in arterial diameter, and blood pressure changes in young adults after a single oral dose of camu camu ( Myrciaria dubia ) pericarp extract or placebo (cross-over design). Ten healthy men and 10 healthy women participated in this study. Ultrasonic diagnostic equipment was used to monitor arterial diameter changes, indicative of FMD, for 110 s after the administration of the camu camu extract or placebo. In addition, the systolic and diastolic blood pressure values were recorded.

Tranexamic acid therapy in ulcerative colitis

PubMed Central

Hollanders, D.; Thomson, Jean M.; Schofield, Phillip F.

1982-01-01

The antifibrinolytic drug tranexamic acid was assessed in controlling bleeding in 12 patients with left-sided proctocolitis. The study was designed as a double-blind cross-over trial employing a dose of 4·5 g of tranexamic acid/day together with identical placebo. A statistically significant reduction in rectal bleeding was achieved in 50% of cases with a minimum of side effects. Sigmoidoscopic grading of rectal mucosal appearances was improved. Frequency of diarrhoea and stool consistency were not altered. Tranexamic acid may have a part to play in the management of selected patients with ulcerative colitis in whom bleeding is difficult to control with orthodox treatment. PMID:6980404

Comparing the efficiency of supersonic oxygen-iodine laser with different mixing designs

NASA Astrophysics Data System (ADS)

Vyskubenko, Boris A.; Adamenkov, A. A.; Bakshin, V. V.; Efremov, V. I.; Ilyin, S. P.; Kolobyanin, Yu. V.; Krukovsky, I. M.; Kudryashov, E. A.; Moiseyev, V. B.

2003-11-01

The paper presents experimental studies of supersonic oxygen-iodine laser (OIL) using twisted-flow singlet oxygen generator (SOG) over a wide range of the singlet oxygen pressures and the buffer gas flow rates. The experiments used different designs of the nozzle unit and mixing system for singlet oxygen and iodine gas with the carrier gas (such as nitrogen or helium). For a wide range of the key parameters, the study looked at the efficiency of supersonic OIL with variation of the singlet oxygen pressure. The measurements were made for different positions of the iodine injection plane with respect to the critical cross-section (both in the subsonic part of the nozzle and in the supersonic flow). The gas pressure at the nozzle unit entry was varied from 50 to 250 Torr. The total pressure loss have been found for different mixing designs. Experimental curves are given for energy performance and chemical efficiency of the supersonic OIL as a function of the key parameters. Comparison is made between the calculated and experimental data. For the optimum conditions of OIL operation, chemical efficiency of 25-30% has been achieved.

How Many Interviews Are Enough to Identify Metathemes in Multisited and Cross-Cultural Research? Another Perspective on Guest, Bunce, and Johnson's (2006) Landmark Study

ERIC Educational Resources Information Center

Hagaman, Ashley K.; Wutich, Amber

2017-01-01

There is much debate over the number of interviews needed to reach data saturation for themes and metathemes in qualitative research. The primary purpose of this study is to determine the number of interviews needed to reach data saturation for metathemes in multisited and cross-cultural research. The analysis is based on a cross-cultural study on…

Novel restricted access to vasectomy in Iran: addressing changing trends in vasectomy clients' characteristics over 16 years in northwestern Iran.

PubMed

Farrokh-Eslamlou, Hamidreza; Oshnouei, Sima; Alinejad, Vahid

2015-11-01

This study is designed to evaluate the popularity of vasectomy in Iran. The study was conducted to calculate the frequency of vasectomy over time, to compare vasectomy users' characteristics with the general population and whether these characteristics have changed over time. A cross-sectional study of 7864 men undergoing vasectomy in a 16-year period was conducted in Urmia, Iran. Comparative statistics described differences between vasectomy users and nonusers. The data were analyzed separately in two 8-year periods, 1996-2003 and 2004-2011. The time period did not involve 2012, the year which vasectomy became outlawed in the whole country. During the study period, the contraceptive prevalence rate of vasectomy increased from 0.1% to 3.35%. Vasectomy users were predominantly older, better educated, had more children and more urban residents than the general male population (p<0.001). Over time, men who underwent vasectomy tended to be younger, have well-educated wife and rural resident (p<0.05). This study highlighted a dramatic rise in the use of vasectomy between 1996 and 2011 in Iran. While the characteristics of vasectomy users versus general population were different, especially in age, education, resident area, number and sex of their children, there were significant changes from two 8-year study time periods. Copyright © 2015 Elsevier Inc. All rights reserved.

Persistent psychological well-being predicts improved self-rated health over 9–10 years: Longitudinal evidence from MIDUS

PubMed Central

Radler, Barry T; Friedman, Elliot M

2015-01-01

Psychological well-being has been linked with better health, but mostly with cross-sectional evidence. Using MIDUS, a national sample of US adults (N = 4963), longitudinal profiles of well-being were used to predict cross-time change in self-reported health over 9–10 years. Well-being was largely stable, although adults differed in whether they had persistently high versus persistently low or moderate levels of well-being. After adjusting for sociodemographic factors, those with persistently high well-being reported better health (subjective health, chronic conditions, symptoms, and functional impairment) across time compared to those with persistently low well-being. Furthermore, persistently high well-being was protective of improved health especially among the educationally disadvantaged. The findings underscore the importance of intervention and educational programs designed to promote well-being for greater segments of society. PMID:26617988

Benchmarking protein classification algorithms via supervised cross-validation.

PubMed

Kertész-Farkas, Attila; Dhir, Somdutta; Sonego, Paolo; Pacurar, Mircea; Netoteia, Sergiu; Nijveen, Harm; Kuzniar, Arnold; Leunissen, Jack A M; Kocsor, András; Pongor, Sándor

2008-04-24

Development and testing of protein classification algorithms are hampered by the fact that the protein universe is characterized by groups vastly different in the number of members, in average protein size, similarity within group, etc. Datasets based on traditional cross-validation (k-fold, leave-one-out, etc.) may not give reliable estimates on how an algorithm will generalize to novel, distantly related subtypes of the known protein classes. Supervised cross-validation, i.e., selection of test and train sets according to the known subtypes within a database has been successfully used earlier in conjunction with the SCOP database. Our goal was to extend this principle to other databases and to design standardized benchmark datasets for protein classification. Hierarchical classification trees of protein categories provide a simple and general framework for designing supervised cross-validation strategies for protein classification. Benchmark datasets can be designed at various levels of the concept hierarchy using a simple graph-theoretic distance. A combination of supervised and random sampling was selected to construct reduced size model datasets, suitable for algorithm comparison. Over 3000 new classification tasks were added to our recently established protein classification benchmark collection that currently includes protein sequence (including protein domains and entire proteins), protein structure and reading frame DNA sequence data. We carried out an extensive evaluation based on various machine-learning algorithms such as nearest neighbor, support vector machines, artificial neural networks, random forests and logistic regression, used in conjunction with comparison algorithms, BLAST, Smith-Waterman, Needleman-Wunsch, as well as 3D comparison methods DALI and PRIDE. The resulting datasets provide lower, and in our opinion more realistic estimates of the classifier performance than do random cross-validation schemes. A combination of supervised and random sampling was used to construct model datasets, suitable for algorithm comparison.

An analysis of characteristics of post-authorisation studies registered on the ENCePP EU PAS Register

PubMed Central

Carroll, Robert; Ramagopalan, Sreeram V.; Cid-Ruzafa, Javier; Lambrelli, Dimitra; McDonald, Laura

2017-01-01

Background: The objective of this study was to investigate the study design characteristics of Post-Authorisation Studies (PAS) requested by the European Medicines Agency which were recorded on the European Union (EU) PAS Register held by the European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (ENCePP). Methods: We undertook a cross-sectional descriptive analysis of all studies registered on the EU PAS Register as of 18 th October 2016. Results: We identified a total of 314 studies on the EU PAS Register, including 81 (26%) finalised, 160 (51%) ongoing and 73 (23%) planned. Of those studies identified, 205 (65%) included risk assessment in their scope, 133 (42%) included drug utilisation and 94 (30%) included effectiveness evaluation. Just over half of the studies (175; 56%) used primary data capture, 135 (43%) used secondary data and 4 (1%) used a hybrid design combining both approaches. Risk assessment and effectiveness studies were more likely to use primary data capture (60% and 85% respectively as compared to 39% and 14% respectively for secondary). The converse was true for drug utilisation studies where 59% were secondary vs. 39% for primary. For type 2 diabetes mellitus, database studies were more commonly used (80% vs 3% chart review, 3% hybrid and 13% primary data capture study designs) whereas for studies in oncology, primary data capture were more likely to be used (85% vs 4% chart review, and 11% database study designs). Conclusions: Results of this analysis show that PAS design varies according to study objectives and therapeutic area. PMID:29188016

Magnetization reversal dynamics in Co nanowires with competing magnetic anisotropies

NASA Astrophysics Data System (ADS)

Pal, Semanti; Saha, Susmita; Polley, Debanjan; Barman, Anjan

2011-12-01

We present the magnetization reversal dynamics of Co nanowires with competing magnetic anisotropies. The aspect ratio ( R) of the nanowires is varied between 2.5 and 60, and we observe a cross-over of the directions of the magnetic easy and hard axes at R=6.8. Micromagnetic simulations qualitatively reproduce the observed cross-over and give detailed insight into the reversal mechanisms associated with the cross-over. The reversal mechanism for a field applied along the long axis of the nanowire exhibits a quasi-coherent rotation mode and a corkscrew-like mode, respectively, above and below the cross-over, with the formation of a Bloch domain near the cross-over region. For a field applied along the short axis, the reversal occurs by nucleation and propagation of reversed domains from the two ends of the nanowires for very high values of the aspect ratio down to the cross-over region, but it transforms into quasi-coherent rotation mode for smaller aspect ratios (below the cross-over region).

Predicting the Intention to Use Condoms and Actual Condom Use Behaviour: A Three-Wave Longitudinal Study in Ghana

PubMed Central

Teye-Kwadjo, Enoch; Kagee, Ashraf; Swart, Hermann

2017-01-01

Background Growing cross-sectional research shows that the theory of planned behaviour (TPB) is robust in predicting intentions to use condoms and condom use behaviour. Yet, little is known about the TPB’s utility in explaining intentions to use condoms and condom use behaviour over time. Methods This study used a longitudinal design and latent variable structural equation modelling to test the longitudinal relationships postulated by the TPB. School-going youths in Ghana provided data on attitudes, subjective norms, perceived control, intentions, and behaviour regarding condom use at three-time points, spaced approximately three-months apart. Results As predicted by the TPB, the results showed that attitudes were significantly positively associated with intentions to use condoms over time. Contrary to the TPB, subjective norms were not significantly associated with intentions to use condoms over time. Perceived control did not predict intentions to use condoms over time. Moreover, intentions to use condoms were not significantly associated with self-reported condom use over time. Conclusion These results suggest that school-going youths in Ghana may benefit from sex education programmes that focus on within-subject attitude formation and activation. The theoretical and methodological implications of these results are discussed. PMID:27925435

Organizing Participation in Cross-Sex Jump Rope: Situating Gender Differences within Longitudinal Studies of Activities.

ERIC Educational Resources Information Center

Goodwin, Marjorie Harness

2001-01-01

Investigates how children use directives and forms of exclusion to organize play activity. Elementary school children of mixed ethnicity were observed playing jump rope over one month. Girls' dominance in the game was observed to change over time. The ability to use actions that tell others what to do in a very direct fashion in cross-sex…

Design and Implementation WebGIS for Improving the Quality of Exploration Decisions at Sin-Quyen Copper Mine, Northern Vietnam

NASA Astrophysics Data System (ADS)

Quang Truong, Xuan; Luan Truong, Xuan; Nguyen, Tuan Anh; Nguyen, Dinh Tuan; Cong Nguyen, Chi

2017-12-01

The objective of this study is to design and implement a WebGIS Decision Support System (WDSS) for reducing uncertainty and supporting to improve the quality of exploration decisions in the Sin-Quyen copper mine, northern Vietnam. The main distinctive feature of the Sin-Quyen deposit is an unusual composition of ores. Computer and software applied to the exploration problem have had a significant impact on the exploration process over the past 25 years, but up until now, no online system has been undertaken. The system was completely built on open source technology and the Open Geospatial Consortium Web Services (OWS). The input data includes remote sensing (RS), Geographical Information System (GIS) and data from drillhole explorations, the drillhole exploration data sets were designed as a geodatabase and stored in PostgreSQL. The WDSS must be able to processed exploration data and support users to access 2-dimensional (2D) or 3-dimensional (3D) cross-sections and map of boreholles exploration data and drill holes. The interface was designed in order to interact with based maps (e.g., Digital Elevation Model, Google Map, OpenStreetMap) and thematic maps (e.g., land use and land cover, administrative map, drillholes exploration map), and to provide GIS functions (such as creating a new map, updating an existing map, querying and statistical charts). In addition, the system provides geological cross-sections of ore bodies based on Inverse Distance Weighting (IDW), nearest neighbour interpolation and Kriging methods (e.g., Simple Kriging, Ordinary Kriging, Indicator Kriging and CoKriging). The results based on data available indicate that the best estimation method (of 23 borehole exploration data sets) for estimating geological cross-sections of ore bodies in Sin-Quyen copper mine is Ordinary Kriging. The WDSS could provide useful information to improve drilling efficiency in mineral exploration and for management decision making.

Fish oil-supplementation increases appetite in healthy adults. A randomized controlled cross-over trial.

PubMed

Damsbo-Svendsen, Signe; Rønsholdt, Mia Dybkjær; Lauritzen, Lotte

2013-07-01

Marine n-3 fatty acids are hypothesized to have beneficial effects on obesity and cancer cachexia possibly via an effect on appetite. The aim of this study was to investigate, if fish oil-supplementation affects appetite in healthy individuals. In a randomized cross-over study, 20 normal-weight subjects (50% females) were given ten 0.5-mL capsules/day of fish oil or soybean oil for 3 weeks separated by 1-week wash-out. In the end of each period, appetite was assessed by 10-cm visual analog scales immediately before and after a standardized breakfast. Results were analyzed in accordance with the paired design considering oil sequence and gender. All subjects completed both periods with a compliance of 96% and oil sequence did not affect the results. There was no difference between the two supplements in any pre-breakfast appetite scores, but the post-prandial sensation of being full was 1.21 cm (0.20; 2.22) lower after the fish oil-period. Furthermore, there was a supplement × gender-interaction on "desire to eat more" due to a score increase of 1.09 cm (0.28; 1.90) in women only. These results suggest that marine n-3 fatty acid may increase appetite. This finding would be potentially beneficial for patients with compromised nutritional status. Copyright © 2013 Elsevier Ltd. All rights reserved.

Using acupressure and Montessori-based activities to decrease agitation for residents with dementia: a cross-over trial.

PubMed

Lin, Li-Chan; Yang, Man-Hua; Kao, Chieh-Chun; Wu, Shiao-Chi; Tang, Sai-Hung; Lin, Jaung-Geng

2009-06-01

To explore the effectiveness of acupressure and Montessori-based activities in decreasing the agitated behaviors of residents with dementia. A double-blinded, randomized (two treatments and one control; three time periods) cross-over design was used. Six special care units for residents with dementia in long-term care facilities in Taiwan were the sites for the study. One hundred thirty-three institutionalized residents with dementia. Subjects were randomized into three treatment sequences: acupressure-presence-Montessori methods, Montessori methods-acupressure-presence and presence-Montessori methods-acupressure. All treatments were done once a day, 6 days per week, for a 4-week period. The Cohen-Mansfield Agitation Inventory, Ease-of-Care, and the Apparent Affect Rating Scale. After receiving the intervention, the acupressure and Montessori-based-activities groups saw a significant decrease in agitated behaviors, aggressive behaviors, and physically nonaggressive behaviors than the presence group. Additionally, the ease-of-care ratings for the acupressure and Montessori-based-activities groups were significantly better than for the presence group. In terms of apparent affect, positive affect in the Montessori-based-activities group was significantly better than in the presence group. This study confirms that a blending of traditional Chinese medicine and a Western activities program would be useful in elderly care and that in-service training for formal caregivers in the use of these interventions would be beneficial for patients

Muscle Activation of Vastus Medialis Oblique and Vastus Lateralis in Sling-Based Exercises in Patients with Patellofemoral Pain Syndrome: A Cross-Over Study

PubMed Central

Chang, Wen-Dien; Huang, Wei-Syuan; Lai, Ping-Tung

2015-01-01

Objectives. To examine what changes are caused in the activity of the vastus medialis oblique (VMO) and vastus lateralis (VL) at the time of sling-based exercises in patients with patellofemoral pain syndrome (PFPS) and compare the muscular activations in patients with PFPS among the sling-based exercises. Methods. This was a cross-over study. Sling-based open and closed kinetic knee extension and hip adduction exercises were designed for PFPS, and electromyography was applied to record maximal voluntary contraction during the exercises. The VMO and VL activations and VMO : VL ratios for the three exercises were analyzed and compared. Results. Thirty male (age = 21.19 ± 0.68 y) and 30 female (age = 21.12 ± 0.74 y) patients with PFPS were recruited. VMO activations during the sling-based open and closed kinetic knee extension exercises were significantly higher (P = 0.04 and P = 0.001) than those during hip adduction exercises and VMO : VL ratio for the sling-based closed kinetic knee extension and hip adduction exercises approximated to 1. Conclusions. The sling-based closed kinetic knee extension exercise produced the highest VMO activation. It also had an appropriate VMO : VL ratio similar to sling-based hip adduction exercise and had beneficial effects on PFPS. PMID:26504480

Effect of aggregation form on bioavailability of zeaxanthin in humans: a randomised cross-over study.

PubMed

Hempel, Judith; Fischer, Anja; Fischer, Monique; Högel, Josef; Bosy-Westphal, Anja; Carle, Reinhold; Schweiggert, Ralf M

2017-11-01

Carotenoid bioavailability from plant and animal food is highly variable depending on numerous factors such as the physical deposition form of carotenoids. As the carotenoid zeaxanthin is believed to play an important role in eye and brain health, we sought to compare the human bioavailability of an H-aggregated with that of a J-aggregated deposition form of zeaxanthin encapsulated into identical formulation matrices. A randomised two-way cross-over study with sixteen participants was designed to compare the post-prandial bioavailability of an H-aggregated zeaxanthin and a J-aggregated zeaxanthin dipalmitate formulation, both delivering 10 mg of free zeaxanthin. Carotenoid levels in TAG-rich lipoprotein fractions were analysed over 9·5 h after test meal consumption. Bioavailability from the J-aggregated formulation (AUC=55·9 nmol h/l) was 23 % higher than from the H-aggregated one (AUC=45·5 nmol h/l), although being only marginally significant (P=0·064). Furthermore, the same formulations were subjected to an internationally recognised in vitro digestion protocol to reveal potential strengths and weaknesses of simulated digestions. In agreement with our human study, liberation of zeaxanthin from the J-aggregated formulation into the simulated duodenal fluids was superior to that from the H-aggregated form. However, micellization rate (bioaccessibility) of the J-aggregated zeaxanthin dipalmitate was lower than that of the H-aggregated zeaxanthin, being contradictory to our in vivo results. An insufficient ester cleavage during simulated digestion was suggested to be the root cause for these observations. In brief, combining our in vitro and in vivo observations, the effect of the different aggregation forms on human bioavailability was lower than expected.

Hybrid bilayer plasmonic metasurface efficiently manipulates visible light.

PubMed

Qin, Fei; Ding, Lu; Zhang, Lei; Monticone, Francesco; Chum, Chan Choy; Deng, Jie; Mei, Shengtao; Li, Ying; Teng, Jinghua; Hong, Minghui; Zhang, Shuang; Alù, Andrea; Qiu, Cheng-Wei

2016-01-01

Metasurfaces operating in the cross-polarization scheme have shown an interesting degree of control over the wavefront of transmitted light. Nevertheless, their inherently low efficiency in visible light raises certain concerns for practical applications. Without sacrificing the ultrathin flat design, we propose a bilayer plasmonic metasurface operating at visible frequencies, obtained by coupling a nanoantenna-based metasurface with its complementary Babinet-inverted copy. By breaking the radiation symmetry because of the finite, yet small, thickness of the proposed structure and benefitting from properly tailored intra- and interlayer couplings, such coupled bilayer metasurface experimentally yields a conversion efficiency of 17%, significantly larger than that of earlier single-layer designs, as well as an extinction ratio larger than 0 dB, meaning that anomalous refraction dominates the transmission response. Our finding shows that metallic metasurface can counterintuitively manipulate the visible light as efficiently as dielectric metasurface (~20% in conversion efficiency in Lin et al.'s study), although the metal's ohmic loss is much higher than dielectrics. Our hybrid bilayer design, still being ultrathin (~λ/6), is found to obey generalized Snell's law even in the presence of strong couplings. It is capable of efficiently manipulating visible light over a broad bandwidth and can be realized with a facile one-step nanofabrication process.

Hybrid bilayer plasmonic metasurface efficiently manipulates visible light

PubMed Central

Qin, Fei; Ding, Lu; Zhang, Lei; Monticone, Francesco; Chum, Chan Choy; Deng, Jie; Mei, Shengtao; Li, Ying; Teng, Jinghua; Hong, Minghui; Zhang, Shuang; Alù, Andrea; Qiu, Cheng-Wei

2016-01-01

Metasurfaces operating in the cross-polarization scheme have shown an interesting degree of control over the wavefront of transmitted light. Nevertheless, their inherently low efficiency in visible light raises certain concerns for practical applications. Without sacrificing the ultrathin flat design, we propose a bilayer plasmonic metasurface operating at visible frequencies, obtained by coupling a nanoantenna-based metasurface with its complementary Babinet-inverted copy. By breaking the radiation symmetry because of the finite, yet small, thickness of the proposed structure and benefitting from properly tailored intra- and interlayer couplings, such coupled bilayer metasurface experimentally yields a conversion efficiency of 17%, significantly larger than that of earlier single-layer designs, as well as an extinction ratio larger than 0 dB, meaning that anomalous refraction dominates the transmission response. Our finding shows that metallic metasurface can counterintuitively manipulate the visible light as efficiently as dielectric metasurface (~20% in conversion efficiency in Lin et al.’s study), although the metal’s ohmic loss is much higher than dielectrics. Our hybrid bilayer design, still being ultrathin (~λ/6), is found to obey generalized Snell’s law even in the presence of strong couplings. It is capable of efficiently manipulating visible light over a broad bandwidth and can be realized with a facile one-step nanofabrication process. PMID:26767195

Approaches to Cross-Cultural Research in Art Education.

ERIC Educational Resources Information Center

Anderson, Frances E.

1979-01-01

The author defines the aims of cross-cultural research in art education and examines the problems inherent in such research, using as an illustration a summary chart of Child's cross-cultural studies of esthetic sensitivity. Emphasis is placed on the need for rigor in research design and execution. (SJL)

Silicone hydrogel mini-scleral contact lenses in early stage after corneal collagen cross-linking for keratoconus: a retrospective case series.

PubMed

Severinsky, Boris; Wajnsztajn, Denise; Frucht-Pery, Joseph

2013-11-01

 The aim was to the evaluate performance of a novel silicone hydrogel mini-scleral contact lens (SHmS) for optical correction of keratoconus in the early stages after the corneal collagen cross-linking procedure (CXL).  We retrospectively analysed the visual acuity improvement and corneal adaptation in the first 10 eyes of nine patients fitted with SHmS lenses one to 3.5 months after corneal collagen cross-linking. The lenses were designed to rest over the patients' sclera and peri-limbal cornea and vault the central cornea with minimal support over it. Visual acuities with manifest refraction and contact lenses, refractive and topographical values (Kmin and Kmax) were evaluated on lens dispensing and after six month of lens wearing. Ocular physiological responses were evaluated using the Institute of Eye Research (IER) grading scales.  SHmS fitting was performed 2.1 ± 0.97 (SD) months after collagen cross-linking. Mean follow up was 10.9 ± 4.41 months (range six to 18 months). Mean decimal visual acuity with SHmS was 0.66 ± 0.22 (approximately 6/9 Snellen fraction, range 0.3 to 0.1) or 0.75 ± 0.14 (approximately 6/8.1, range 0.5 to 1.0), when omitting two amblyopic eyes. Nine (90 per cent) eyes were successfully fitted, that is, able to wear the lenses for 10 hours per day or longer. Mean wearing time was 11.7 hours (range six to 14) per day. No corneal neovascularisation or papillary reaction was found in all fitted eyes.  SHmS contact lenses provide successful visual rehabilitation shortly after corneal collagen cross-linking. This new soft contact lens design with scleral fixation and minimal apical touch was demonstrated to be safe shortly after collagen cross-linking, as the avoidance of contact with the treated zone minimises contact lens influence on corneal recovery. © 2013 The Authors. Clinical and Experimental Optometry © 2013 Optometrists Association Australia.

Recognition of Cross-Cultural Meaning When Developing Online Web Displays.

ERIC Educational Resources Information Center

Brown, Ian; Hedberg, John

The perceptions and practical experiences are important influences when creating and developing online learning experiences in cross cultural contexts. In this study, 15 educational designers studying for their Master's Degree were asked to contribute their interpretations to an ongoing study of what meaning and interpretations were generated from…

Urban form and older residents' service use, walking, driving, quality of life, and neighborhood satisfaction.

PubMed

Patterson, Patricia K; Chapman, Nancy J

2004-01-01

This study explored the relationship between pedestrian-friendly urban form as reflected in new urbanism design guidelines, and neighborhood service use, walking, driving, quality of life, and neighborhood satisfaction among older women. A cross-sectional survey compared residents of census tracts similar indemographic characteristics but differing in urban form. The setting was urban and suburban areas of Portland, Oregon. The sample consisted of 372 females living alone over age 70 in six census tracts; 133 (36%) completed surveys. The New Urbanism Index rated the physical features of respondents' neighborhoods. The Neighborhood Resident Survey assessed travel modes and neighborhood satisfaction. The Quality of Life Index measured resident well-being. The Dartmouth COOP Functional Health Charts measured health status. Group comparisons were made with t-tests and regression analysis. Although limited by the cross-sectional design, the study showed that new urbanism partially explained several differences in service use and activity: distance to a grocery store (r2 change = .11, p = .001), number of services used within 1 mile from home (r2 change = .06, p = .007), number of walking activities (r2 change = .08, p = .001), number of services accessed by walking (r2 change = .14, p = .000), and number of services accessed by driving (r2 change = .05, p = .001). Traditional urban neighborhoods with mixed services and good pedestrian access were associated with increased walking among older residents.

Inflammation and Arterial Stiffness in Chronic Kidney Disease: Findings From the CRIC Study.

PubMed

Peyster, Eliot; Chen, Jing; Feldman, Harold I; Go, Alan S; Gupta, Jayanta; Mitra, Nandita; Pan, Qiang; Porter, Anna; Rahman, Mahboob; Raj, Dominic; Reilly, Muredach; Wing, Maria R; Yang, Wei; Townsend, Raymond R

2017-04-01

Chronic kidney disease (CKD) and arterial stiffness are associated with increased cardiovascular morbidity and mortality. Inflammation is proposed to have a role in the development of arterial stiffness, and CKD is recognized as a proinflammatory state. Arterial stiffness is increased in CKD, and cross-sectional data has suggested a link between increased inflammatory markers in CKD and higher measures of arterial stiffness. However, no large scale investigations have examined the impact of inflammation on the progression of arterial stiffness in CKD. We performed baseline assessments of 5 inflammatory markers in 3,939 participants from the chronic renal insufficiency cohort (CRIC), along with serial measurements of arterial stiffness at 0, 2, and 4 years of follow-up. A total of 2,933 participants completed each of the follow-up stiffness measures. In cross-sectional analysis at enrollment, significant associations with at least 2 measures of stiffness were observed for fibrinogen, interleukin-6, high-sensitivity C-reactive protein, proteinuria, and composite inflammation score after adjustment for confounders. In longitudinal analyses, there were few meaningful correlations between baseline levels of inflammation and changes in metrics of arterial stiffness over time. In a large cohort of CKD participants, we observed multiple significant correlations between initial markers of inflammation and metrics of arterial stiffness, but baseline inflammation did not predict changes in arterial stiffness over time. While well-described biologic mechanisms provide the basis for our understanding of the cross-sectional results, continued efforts to design longitudinal studies are necessary to fully elucidate the relationship between chronic inflammation and arterial stiffening. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Employment contracts: cross-sectional and longitudinal relations with quality of working life, health and well-being.

PubMed

Kompier, Michiel; Ybema, Jan Fekke; Janssen, Julia; Taris, Toon

2009-01-01

The aim of this study was to enhance (i) insight in the relationship between different types of employment contract and the quality of working life, health and well-being, and (ii) our causal understanding of these relationships by comparing employees whose contract type changes across time. Analyses were based on a two-year prospective cohort study. Cross-sectional analyses were based upon a sample of 2,454 Dutch employees (2004). Longitudinal data were available for 1,865 respondents (2004-2006). We distinguished among 5 contract types, and subgroups of 'Upward' (i.e., towards permanent employment) and 'Downward' (towards temporary employment) movers across time. Data were analysed with analysis of variance and cross table analysis. Cross-sectionally, we found differences between contract types in quality of working life: generally permanent employees had better jobs, whereas temporary agency workers and on call workers had more 'bad work characteristics'. We also found a difference in health behaviour (smoking) and that psychological health was worst among temporary agency workers. In longitudinal analyses we found some evidence that a positive change in employment contract was associated with a better quality of working life and better psychological health, whereas the opposite was true for a negative contract change. The quality of working life, health and well-being are unequally distributed over employment contract groups. Temporary agency workers and on-call workers deserve special attention in terms of job design and human resource management.

Cross-Validation of easyCBM Reading Cut Scores in Oregon: 2009-2010. Technical Report #1108

ERIC Educational Resources Information Center

Park, Bitnara Jasmine; Irvin, P. Shawn; Anderson, Daniel; Alonzo, Julie; Tindal, Gerald

2011-01-01

This technical report presents results from a cross-validation study designed to identify optimal cut scores when using easyCBM[R] reading tests in Oregon. The cross-validation study analyzes data from the 2009-2010 academic year for easyCBM[R] reading measures. A sample of approximately 2,000 students per grade, randomly split into two groups of…

Social Capital, Economic Development, and Homicide: A Cross-National Investigation

ERIC Educational Resources Information Center

Robbins, Blaine; Pettinicchio, David

2012-01-01

This article draws from an ongoing debate over explanations of homicide. Within this debate, we investigate the pro-social effects of civil society and social capital. Few cross-national studies explore whether elements of social capital either increase or decrease homicide. The cross-national work that does is often characterized by small,…

Unresolved legal questions in cross-border health care in Europe: liability and data protection.

PubMed

van der Molen, I N; Commers, M J

2013-11-01

Directive 2011/24/EU was designed to clarify the rights of EU citizens in evaluating, accessing and obtaining reimbursement for cross-border care. Based on three regional case studies, the authors attempted to assess the added value of the Directive in helping clarify issues in to two key areas that have been identified as barriers to cross-border care: liability and data protection. Qualitative case study employing secondary data sources including research of jurisprudence, that set up a Legal framework as a base to investigate liability and data protection in the context of cross-border projects. By means of three case studies that have tackled liability and data protection hurdles in cross-border care implementation, this article attempts to provide insight into legal certainty and uncertainty regarding cross-border care in Europe. The case studies reveal that the Directive has not resolved core uncertainties related to liability and data protection issues within cross-border health care. Some issues related to the practice of cross-border health care in Europe have been further clarified by the Directive and some direction has been given to possible solutions for issues connected to liability and data protection. Directive 2011/24/EU is clearly a transposition of existing regulations on data protection and ECJ case law, plus a set of additional, mostly, voluntary rules that might enhance regional border cooperation. Therefore, as shown in the case studies, a practical and case by case approach is still necessary in designing and providing cross-border care. © 2013 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Vascular provisions for a local utero-ovarian cross-over pathway in new world camelids.

PubMed

Del Campo, M R; Del Campo, C H; Ginther, O J

1996-10-15

The right uterine horn of alpacas causes luteolysis in the right ovary, whereas the left horn causes luteolysis in both ovaries. Female reproductive tracts were studied in 32 adult llamas, 12 adult alpacas, and 21 mid-gestation female fetuses to determine if there is a dichotomy in the vascular anatomy between the 2 sides. Adult tracts were studied by either injection of colored latex into the veins and arteries followed by tissue clearing or by injection of colored fluids during transillumination. Fetal uteri were studied by transillumination. The angioarchitecture of the ovarian vascular pedicle was similar to that reported for ewes. There was no vessel comparable to the middle uterine artery, which is the largest uterine artery in the other farm species. A striking difference from the uterine vascular of other farm species was the presence of a major branch of the right uterine artery that crossed the cranial intercornual area to supply much of the left uterine horn. A corresponding major vein originated from the left horn, crossed the mid-line, and terminated as a branch of the right uterine vein. Thus, the vascular anatomy indicated that much venous blood from the left horn drained to the right side. This was confirmed by injection of colored fluid into a small venous branch at the tip of the left horn. The prominent cross-over vessels were observed in the fetal uteri, and the diameter of the left uterine fetal horn (6.7 +/- 0.6 mm) was greater (P < 0.001) than the diameter of the right horn (5.8 +/- 0.5 mm). The presence of a large cross-over vein traversing from the left horn to the right side is compatible with the hypothesis that the left horn can exert luteolytic control over the corpus luteum in the right ovary through a veno-arterial pathway. The area of veno-arterial transfer of the luteolysin from a vein containing blood from the left horn into an artery supplying the right ovary was not defined in this study. However, the results provide an anatomical basis for functional testing of the cross-over hypothesis and defining the area of venoarterial transfer in camelids.

Prospective Prediction of Nonsuicidal Self-Injury: A 1-Year Longitudinal Study in Young Adults

ERIC Educational Resources Information Center

Glenn, Catherine R.; Klonsky, E. David

2011-01-01

Nonsuicidal self-injury (NSSI) has become a significant public health problem. Although numerous studies have examined cross-sectional psychological correlates of NSSI, there has been little research examining predictors of NSSI over time. The present study examined cross-sectional and longitudinal correlates of NSSI in 81 young adult…

EVALUATION OF ENGINEERING CONTROLS FOR THE MIXING OF FLAVORINGS CONTAINING DIACETYL AND OTHER VOLATILE INGREDIENTS

PubMed Central

Hirst, Deborah V.L.; Dunn, Kevin H.; Shulman, Stanley A.; Hammond, Duane R.; Sestito, Nicholas

2015-01-01

Exposures to diacetyl, a primary ingredient of butter flavoring, have been shown to cause respiratory disease among workers who mix flavorings. This study focused on evaluating ventilation controls designed to reduce emissions from the flavor mixing tanks, the major source of diacetyl in the plants. Five exhaust hood configurations were evaluated in the laboratory: standard hinged lid-opened, standard hinged lid-closed, hinged lid-slotted, dome with 38-mm gap, and dome with 114-mm gap. Tracer gas tests were performed to evaluate quantitative capture efficiency for each hood. A perforated copper coil was used to simulate an area source within the 1.2-meter diameter mixing tank. Capture efficiencies were measured at four hood exhaust flow rates (2.83, 5.66, 11.3, and 17.0 cubic meters per minute) and three cross draft velocities (0, 30, and 60 meters per minute). All hoods evaluated performed well with capture efficiencies above 90% for most combinations of exhaust volume and cross drafts. The standard hinged lid was the least expensive to manufacture and had the best average capture efficiency (over 99%) in the closed configuration for all exhaust flow rates and cross drafts. The hinged lid-slotted hood had some of the lowest capture efficiencies at the low exhaust flow rates compared to the other hood designs. The standard hinged lid performed well, even in the open position, and it provided a flexible approach to controlling emissions from mixing tanks. The dome hood gave results comparable to the standard hinged lid but it is more expensive to manufacture. The results of the study indicate that emissions from mixing tanks used in the production of flavorings can be controlled using simple inexpensive exhaust hoods. PMID:24649880

Temporal development of near-native functional properties and correlations with qMRI in self-assembling fibrocartilage treated with exogenous lysyl oxidase homolog 2.

PubMed

Hadidi, Pasha; Cissell, Derek D; Hu, Jerry C; Athanasiou, Kyriacos A

2017-12-01

Advances in cartilage tissue engineering have led to constructs with mechanical integrity and biochemical composition increasingly resembling that of native tissues. In particular, collagen cross-linking with lysyl oxidase has been used to significantly enhance the mechanical properties of engineered neotissues. In this study, development of collagen cross-links over time, and correlations with tensile properties, were examined in self-assembling neotissues. Additionally, quantitative MRI metrics were examined in relation to construct mechanical properties as well as pyridinoline cross-link content and other engineered tissue components. Scaffold-free meniscus fibrocartilage was cultured in the presence of exogenous lysyl oxidase, and assessed at multiple time points over 8weeks starting from the first week of culture. Engineered constructs demonstrated a 9.9-fold increase in pyridinoline content, reaching 77% of native tissue values, after 8weeks of culture. Additionally, engineered tissues reached 66% of the Young's modulus in the radial direction of native tissues. Further, collagen cross-links were found to correlate with tensile properties, contributing 67% of the tensile strength of engineered neocartilages. Finally, examination of quantitative MRI metrics revealed several correlations with mechanical and biochemical properties of engineered constructs. This study displays the importance of culture duration for collagen cross-link formation, and demonstrates the potential of quantitative MRI in investigating properties of engineered cartilages. This is the first study to demonstrate near-native cross-link content in an engineered tissue, and the first study to quantify pyridinoline cross-link development over time in a self-assembling tissue. Additionally, this work shows the relative contributions of collagen and pyridinoline to the tensile properties of collagenous tissue for the first time. Furthermore, this is the first investigation to identify a relationship between qMRI metrics and the pyridinoline cross-link content of an engineered collagenous tissue. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

A Rigid Mid-Lift-to-Drag Ratio Approach to Human Mars Entry, Descent, and Landing

NASA Technical Reports Server (NTRS)

Cerimele, Christopher J.; Robertson, Edward A.; Sostaric, Ronald R.; Campbell, Charles H.; Robinson, Phil; Matz, Daniel A.; Johnson, Breanna J.; Stachowiak, Susan J.; Garcia, Joseph A.; Bowles, Jeffrey V.;

Towards Phosphate Detection in Hydroponics Using Molecularly Imprinted Polymer Sensors.

PubMed

Storer, Christopher S; Coldrick, Zachary; Tate, Daniel J; Donoghue, Jack Marsden; Grieve, Bruce

2018-02-10

An interdigitated electrode sensor was designed and microfabricated for measuring the changes in the capacitance of three phosphate selective molecularly imprinted polymer (MIP) formulations, in order to provide hydroponics users with a portable nutrient sensing tool. The MIPs investigated were synthesised using different combinations of the functional monomers methacrylic acid (MAA) and N -allylthiourea, against the template molecules diphenyl phosphate, triethyl phosphate, and trimethyl phosphate. A cross-interference study between phosphate, nitrate, and sulfate was carried out for the MIP materials using an inductance, capacitance, and resistance (LCR) meter. Capacitance measurements were taken by applying an alternating current (AC) with a potential difference of 1 V root mean square (RMS) at a frequency of 1 kHz. The cross-interference study demonstrated a strong binding preference to phosphate over the other nutrient salts tested for each formulation. The size of template molecule and length of the functional monomer side groups also determined that a short chain functional monomer in combination with a template containing large R-groups produced the optimal binding site conditions when synthesising a phosphate selective MIP.

Towards Phosphate Detection in Hydroponics Using Molecularly Imprinted Polymer Sensors

PubMed Central

Storer, Christopher S.; Coldrick, Zachary; Donoghue, Jack Marsden

2018-01-01

An interdigitated electrode sensor was designed and microfabricated for measuring the changes in the capacitance of three phosphate selective molecularly imprinted polymer (MIP) formulations, in order to provide hydroponics users with a portable nutrient sensing tool. The MIPs investigated were synthesised using different combinations of the functional monomers methacrylic acid (MAA) and N-allylthiourea, against the template molecules diphenyl phosphate, triethyl phosphate, and trimethyl phosphate. A cross-interference study between phosphate, nitrate, and sulfate was carried out for the MIP materials using an inductance, capacitance, and resistance (LCR) meter. Capacitance measurements were taken by applying an alternating current (AC) with a potential difference of 1 V root mean square (RMS) at a frequency of 1 kHz. The cross-interference study demonstrated a strong binding preference to phosphate over the other nutrient salts tested for each formulation. The size of template molecule and length of the functional monomer side groups also determined that a short chain functional monomer in combination with a template containing large R-groups produced the optimal binding site conditions when synthesising a phosphate selective MIP. PMID:29439386

Effects over time of self-reported direct and vicarious racial discrimination on depressive symptoms and loneliness among Australian school students.

PubMed

Priest, Naomi; Perry, Ryan; Ferdinand, Angeline; Kelaher, Margaret; Paradies, Yin

2017-02-03

Racism and racial discrimination are increasingly acknowledged as a critical determinant of health and health inequalities. However, patterns and impacts of racial discrimination among children and adolescents remain under-investigated, including how different experiences of racial discrimination co-occur and influence health and development over time. This study examines associations between self-reported direct and vicarious racial discrimination experiences and loneliness and depressive symptoms over time among Australian school students. Across seven schools, 142 students (54.2% female), age at T1 from 8 to 15 years old (M = 11.14, SD = 2.2), and from diverse racial/ethnic and migration backgrounds (37.3% born in English-speaking countries as were one or both parents) self-reported racial discrimination experiences (direct and vicarious) and mental health (depressive symptoms and loneliness) at baseline and 9 months later at follow up. A full cross-lagged panel design was modelled using MPLUS v.7 with all variables included at both time points. A cross-lagged effect of perceived direct racial discrimination on later depressive symptoms and on later loneliness was found. As expected, the effect of direct discrimination on both health outcomes was unidirectional as mental health did not reciprocally influence reported racism. There was no evidence that vicarious racial discrimination influenced either depressive symptoms or loneliness beyond the effect of direct racial discrimination. Findings suggest direct racial discrimination has a persistent effect on depressive symptoms and loneliness among school students over time. Future work to explore associations between direct and vicarious discrimination is required.

Development of a high stability pointing mechanism for wide application

NASA Technical Reports Server (NTRS)

Brunnen, A. J. D.; Bentall, R. H.

1982-01-01

A recurrent requirement of spaceborne instruments and communications equipment is that of accurate pointing. This need is recognizable in such diverse applications as Star Sensor trimming, Momentum Wheel gimballing, in-orbit adjustment or alignment of equipment, inter-satellite communication and Antenna Pointing. A pointing mechanism of novel design having several advantages over the more conventional gimbal, centre-pivoted, or cross axis pointing concepts is described.

Nonshared Environmental Mediation of the Association between Deviant Peer Affiliation and Adolescent Externalizing Behaviors over Time: Results from a Cross-Lagged Monozygotic Twin Differences Design

ERIC Educational Resources Information Center

Burt, S. Alexandra; McGue, Matt; Iacono, William G.

2009-01-01

It has been argued that peers are the most important agent of adolescent socialization and, more specifically, that this socialization process occurs at the child-specific (or nonshared environmental) level (J. R. Harris, 1998; R. Plomin & Asbury, 2005). The authors sought to empirically evaluate this nonshared environmental peer influence…

Comparison of ELISA and LC-MS/MS for the measurement of flunixin plasma concentrations in beef cattle after intravenous and subcutaneous administration

USDA-ARS?s Scientific Manuscript database

The feasibility of using an enzyme linked immunosorbant assay (ELISA) with only simple preparation steps to determine flunixin plasma concentrations in healthy beef cattle was explored. Eight cattle (288 ± 22 kg) were treated with 2.2 mg/kg bw flunixin free acid in a cross-over design by subcutaneo...

Stirling engine design manual

NASA Technical Reports Server (NTRS)

Martini, W. R.

1978-01-01

This manual is intended to serve both as an introduction to Stirling engine analysis methods and as a key to the open literature on Stirling engines. Over 800 references are listed and these are cross referenced by date of publication, author and subject. Engine analysis is treated starting from elementary principles and working through cycles analysis. Analysis methodologies are classified as first, second or third order depending upon degree of complexity and probable application; first order for preliminary engine studies, second order for performance prediction and engine optimization, and third order for detailed hardware evaluation and engine research. A few comparisons between theory and experiment are made. A second order design procedure is documented step by step with calculation sheets and a worked out example to follow. Current high power engines are briefly described and a directory of companies and individuals who are active in Stirling engine development is included. Much remains to be done. Some of the more complicated and potentially very useful design procedures are now only referred to. Future support will enable a more thorough job of comparing all available design procedures against experimental data which should soon be available.

Improvement in health-related quality of life after therapy with omeprazole in patients with coronary artery disease and recurrent angina-like chest pain. A double-blind, placebo-controlled trial of the SF-36 survey

PubMed Central

2011-01-01

Background Many patients with coronary artery disease (CAD) have overlapping gastroenterological causes of recurrent chest pain, mainly due to gastroesophageal reflux (GER) and aspirin-induced gastrointestinal tract damage. These symptoms can be alleviated by proton pump inhibitors (PPIs). The study addressed whether omeprazole treatment also affects general health-related quality of life (HRQL) in patients with CAD. Study 48 patients with more than 50% narrowing of the coronary arteries on angiography without clinically overt gastrointestinal symptoms were studied. In a double-blind, placebo-controlled, cross-over study design, patients were randomized to take omeprazole 20 mg bid or a placebo for two weeks, and then crossed over to the other study arm. The SF-36 questionnaire was completed before treatment and again after two weeks of therapy. Results Patients treated with omeprazole in comparison to the subjects taking the placebo had significantly greater values for the SF-36 survey (which relates to both physical and mental health), as well as for bodily pain, general health perception, and physical health. In comparison to the baseline values, therapy with omeprazole led to a significant increase in the three summarized health components: total SF-36; physical and mental health; and in the following detailed health concept scores: physical functioning, limitations due to physical health problems, bodily pain and emotional well-being. Conclusions A double dose of omeprazole improved the general HRQL in patients with CAD without severe gastrointestinal symptoms more effectively than the placebo. PMID:21939510

A method for (n,alpha) and (n,p) cross section measurements using a lead slowing-down spectrometer

NASA Astrophysics Data System (ADS)

Thompson, Jason Tyler

The need for nuclear data comes from several sources including astrophysics, stockpile stewardship, and reactor design. Photodisintegration, neutron capture, and charged particle out reactions on stable or short-lived radioisotopes play crucial roles during stellar evolution and forming solar isotopic abundances whereas these reactions can affect the safety of our national weapons stockpile or criticality and safety calculations for reactors. Although models can be used to predict some of these values, these predictions are only as good as the experimental data that constrains them. For neutron-induced emission of α particles and protons ((n,α) and (n,p) reactions) at energies below 1 MeV, the experimental data is at best scarce and models must rely on extrapolations from unlike situations, (i.e. different reactions, isotopes, and energies) providing ample room for uncertainty. In this work a new method of measuring energy dependent (n,α) and (n,p) cross sections was developed for the energy range of 0.1 eV - ˜100 keV using a lead slowing-down spectrometer (LSDS). The LSDS provides a ˜10 4 neutron flux increase over the more conventionally used time-of-flight (ToF) methods at equivalent beam conditions, allowing for the measurement of small cross sections (µb’s to mb’s) while using small sample masses (µg’s to mg’s). Several detector concepts were designed and tested, including specially constructed Canberra passivated, implanted, planar silicon (PIPS) detectors; and gas-electron-multiplier (GEM) foils. All designs are compensated to minimize γ-flash problems. The GEM detector was found to function satisfactory for (n,α) measurements, but the PIPS detectors were found to be better suited for (n,p) reaction measurements. A digital data acquisition (DAQ) system was programmed such that background can be measured simultaneously with the reaction cross section. Measurements of the 147Sm(n,α)144Nd and 149 Sm(n,α)146Nd reaction cross sections were performed as proofs of concept. The measurement of 147Sm verified and extended a previous measurement while the measurement of 149Sm is the first over the majority of the 0.1 eV to 100 keV energy region.

Probiotic strain Lactobacillus plantarum 299v increases iron absorption from an iron-supplemented fruit drink: a double-isotope cross-over single-blind study in women of reproductive age.

PubMed

Hoppe, Michael; Önning, Gunilla; Berggren, Anna; Hulthén, Lena

2015-10-28

Iron deficiency is common, especially among young women. Adding probiotics to foods could be one way to increase iron absorption. The aim of this study was to test the hypothesis that non-haem iron absorption from a fruit drink is improved by adding Lactobacillus plantarum 299v (Lp299v). Iron absorption was studied in healthy women of reproductive age using a single-blind cross-over design in two trials applying the double-isotope (55Fe and 59Fe) technique. In Trial 1, iron absorption from a fruit drink containing 109 colony-forming units (CFU) Lp299v was compared with that from a control drink without Lp299v. Trial 2 had the same design but 1010 CFU were used. The test and control drinks contained approximately 5 mg of iron as ferrous lactate and were labelled with 59Fe (B) and 55Fe (A), respectively, and consumed on 4 consecutive days in the order AABB. Retention of the isotopes was measured with whole-body counting and in blood. Mean iron absorption from the drink containing 109 CFU Lp299v (28·6(sd 12·5) %) was significantly higher than from the control drink (18·5(sd 5·8) %), n 10, P<0·028). The fruit drink with 1010 CFU Lp299v gave a mean iron absorption of 29·1(sd 17·0) %, whereas the control drink gave an absorption of (20·1(sd 6·4) %) (n 11, P<0·080). The difference in iron absorption between the 109 CFU Lp299v and the 1010 CFU Lp299v drinks was not significant (P=0·941). In conclusion, intake of probiotics can increase iron absorption by approximately 50 % from a fruit drink having an already relatively high iron bioavailability.

EFFECT of daily antiseptic body wash with octenidine on nosocomial primary bacteraemia and nosocomial multidrug-resistant organisms in intensive care units: design of a multicentre, cluster-randomised, double-blind, cross-over study

PubMed Central

Meißner, Anne; Hasenclever, Dirk; Brosteanu, Oana; Chaberny, Iris Freya

2017-01-01

Introduction Nosocomial infections are serious complications that increase morbidity, mortality and costs and could potentially be avoidable. Antiseptic body wash is an approach to reduce dermal micro-organisms as potential pathogens on the skin. Large-scale trials with chlorhexidine as the antiseptic agent suggest a reduction of nosocomial infection rates. Octenidine is a promising alternative agent which could be more effective against Gram-negative organisms. We hypothesise that daily antiseptic body wash with octenidine reduces the risk of intensive care unit (ICU)-acquired primary bacteraemia and ICU-acquired multidrug-resistant organisms (MDRO) in a standard care setting. Methods and analysis EFFECT is a controlled, cluster-randomised, double-blind study. The experimental intervention consists in using octenidine-impregnated wash mitts for the daily routine washing procedure of the patients. This will be compared with using placebo wash mitts. Replacing existing washing methods is the only interference into clinical routine. Participating ICUs are randomised in an AB/BA cross-over design. There are two 15-month periods, each consisting of a 3-month wash-out period followed by a 12-month intervention and observation period. Randomisation determines only the sequence in which octenidine-impregnated or placebo wash mitts are used. ICUs are left unaware of what mitts packages they are using. The two coprimary endpoints are ICU-acquired primary bacteraemia and ICU-acquired MDRO. Endpoints are defined based on individual ward-movement history and microbiological test results taken from the hospital information systems without need for extra documentation. Data on clinical symptoms of infection are not collected. EFFECT aims at recruiting about 45 ICUs with about 225 000 patient-days per year. Ethics and dissemination The study was approved by the ethics committee of the University of Leipzig (number 340/16-ek) in November 2016. Findings will be published in peer-reviewed journals. Trial registration number DRKS-ID: DRKS00011282. PMID:29122787

Effects of Acute Exercise on Resting EEG in Children with Attention-Deficit/Hyperactivity Disorder.

PubMed

Huang, Chung-Ju; Huang, Ching-Wen; Hung, Chiao-Ling; Tsai, Yu-Jung; Chang, Yu-Kai; Wu, Chien-Ting; Hung, Tsung-Min

2018-06-05

This two stage study examined the effects of acute exercise on resting electroencephalographic (EEG) patterns of children with attention-deficit hyperactivity disorder (ADHD). The first stage compared the neural oscillatory patterns of children with and without ADHD. Resting EEGs were recorded under an open-eyes condition from 24 boys with ADHD and 28 matched controls. The second stage of the study employed a randomized cross-over trial design. The 24 boys with ADHD engaged in a 30-min intervention that consisted of either running on a treadmill or watching a video on alternative days, with resting EEGs recorded before and after treatment. The first stage found that children with ADHD exhibited significantly higher theta/beta ratios over the midline electrodes sites than controls. The second stage further indicated that children with ADHD displayed smaller theta/beta ratios following the exercise condition compared with the video-watching condition. This finding suggests that acute exercise normalizes arousal and alertness of children with ADHD, as reflected in resting EEG readings.

Draw-and-Write Technique Elicits Children's Perceptions of Health in the USA and Guatemala

ERIC Educational Resources Information Center

Renslow, Jillian; Maupin, Jonathan

2018-01-01

Objective: Using the draw-and-write methodology, this study examined cross-cultural similarities and differences in children's perceptions of health. Design: Cross-sectional design. Setting: One public elementary school in the USA and in Guatemala. Method: The total sample included 161 children 9-10 years of age, 80 in the USA and 81 in Guatemala.…

Importance of Preserving Cross-correlation in developing Statistically Downscaled Climate Forcings and in estimating Land-surface Fluxes and States

NASA Astrophysics Data System (ADS)

Das Bhowmik, R.; Arumugam, S.

2015-12-01

Multivariate downscaling techniques exhibited superiority over univariate regression schemes in terms of preserving cross-correlations between multiple variables- precipitation and temperature - from GCMs. This study focuses on two aspects: (a) develop an analytical solutions on estimating biases in cross-correlations from univariate downscaling approaches and (b) quantify the uncertainty in land-surface states and fluxes due to biases in cross-correlations in downscaled climate forcings. Both these aspects are evaluated using climate forcings available from both historical climate simulations and CMIP5 hindcasts over the entire US. The analytical solution basically relates the univariate regression parameters, co-efficient of determination of regression and the co-variance ratio between GCM and downscaled values. The analytical solutions are compared with the downscaled univariate forcings by choosing the desired p-value (Type-1 error) in preserving the observed cross-correlation. . For quantifying the impacts of biases on cross-correlation on estimating streamflow and groundwater, we corrupt the downscaled climate forcings with different cross-correlation structure.

Intracycle angular velocity control of cross-flow turbines

NASA Astrophysics Data System (ADS)

Strom, Benjamin; Brunton, Steven L.; Polagye, Brian

2017-08-01

Cross-flow turbines, also known as vertical-axis turbines, are attractive for power generation from wind and water currents. Some cross-flow turbine designs optimize unsteady fluid forces and maximize power output by controlling blade kinematics within one rotation. One established method is to dynamically pitch the blades. Here we introduce a mechanically simpler alternative: optimize the turbine rotation rate as a function of angular blade position. We demonstrate experimentally that this approach results in a 59% increase in power output over standard control methods. Analysis of fluid forcing and blade kinematics suggest that power increase is achieved through modification of the local flow conditions and alignment of fluid force and rotation rate extrema. The result is a low-speed, structurally robust turbine that achieves high efficiency and could enable a new generation of environmentally benign turbines for renewable power generation.

Cross-sectional and longitudinal associations of functional and health status with institutional care use: results from the Survey of Health and Living Status of the Elderly in Taiwan.

PubMed

Tsai, Hsin-Jen

2013-07-01

This study evaluated the cross-sectional and longitudinal associations of functional and health status with institutional care, and examined determinants of institutional care use over time. Data of this study were obtained from the Survey of Health and Living Status of the Elderly in Taiwan (SHLSET), which was launched in 1989 and involved a nationally representative sample of nearly-old and old Taiwanese. The baseline data in this present study were collected in 1999, and followed in 2003 and 2007. Participants with institutional care use had a higher activities of daily living (ADL) score, more self-reported diseases and poorer self-reported health status than participants without institutional care use (all P<0.05). Cross-sectional analysis showed that a higher ADL score, having heart diseases and having a stroke were positively associated with institutional care use (P<0.05); whereas the number of self-reported diseases and poor self-reported health status were not associated with institutional care use. Longitudinal analysis showed that increased ADL scores and the number of self-reported diseases over 4- and 8 years were associated with an increased likelihood of subsequent institutional care use (all P<0.05). Worsening health status over 4 years was associated with an increased likelihood of subsequent institutional care use, but this association did not exist over 8 years. Only ADL and ADL deterioration over time are cross-sectionally and longitudinally associated with increased institutional care use. Declining functional status is a major determinant of institutional care use for Taiwanese aged over 53 years. © 2012 Japan Geriatrics Society.

Fan-shaped antennas: Realization of wideband characteristics and generation of stop bands

NASA Astrophysics Data System (ADS)

Nakano, H.; Morishita, K.; Iitsuka, Y.; Mimaki, H.; Yoshida, T.; Yamauchi, J.

2008-08-01

This paper presents four fan-shaped antennas: U.S.-FAN, CROSS-FAN, CROSS-FAN-W, and CROSS-FAN-S. Each of these antennas stands upright above a ground plane, and has edges expressed by an exponential function and a circle function. The four antennas are investigated using frequencies from 1.5 GHz to 11 GHz. The CROSS-FAN is found to have a lower VSWR over a wide frequency band compared to the U.S.-FAN. The CROSS-FAN-W and CROSS-FAN-S are modified versions of the CROSS-FAN, each designed to have a stop band (a high VSWR frequency range) for interference cancellation. The stop band for the CROSS-FAN-W is controlled by a wire (total length 4Lwire) that connects the fan-shaped elements. The center frequency of the stop band fstop is close to the frequency corresponding to a wire segment length Lwire of half the wavelength. It is also found that the stop band in the CROSS-FAN-S can be controlled by four slots, one cut into each of the fan-shaped elements. The center frequency of the stop band fstop is close to the frequency corresponding to a slot length Lslot of one-quarter of the wavelength. Experimental work is performed to confirm the theoretical results, using the CROSS-FAN-S.

Behaviour of Reinforced Concrete Columns of Various Cross-Sections Subjected to Fire

NASA Astrophysics Data System (ADS)

Balaji, Aneesha; Muhamed Luquman, K.; Nagarajan, Praveen; Madhavan Pillai, T. M.

2016-09-01

Fire resistance is one of the crucial design regulations which are now mandatory in most of the design codes. Therefore, a thorough knowledge of behaviour of structures exposed to fire is required in this aspect. Columns are the most vulnerable structural member to fire as it can be exposed to fire from all sides. However, the data available for fire resistant design for columns are limited. Hence the present work is focused on the effect of cross-sectional shape of column in fire resistance design. The various cross-sections considered are Square, Ell (L), Tee (T), and Plus (`+') shape. Also the effect of size and shape and distribution of steel reinforcement on fire resistance of columns is studied. As the procedure for determining fire resistance is not mentioned in Indian Standard code IS 456 (2000), the simplified method (500 °C isotherm method) recommended in EN 1992-1-2:2004 (E) (Eurocode 2) is adopted. The temperature profiles for various cross-sections are developed using finite element method and these profiles are used to predict fire resistance capability of compression members. The fire resistance based on both numerical and code based methods are evaluated and compared for various types of cross-section.

Border Crossings: Engaging Students in Diversity Work and Intergroup Relations

ERIC Educational Resources Information Center

Rose, Susan D.; Bylander, Joyce

2007-01-01

As an innovative model for diversity education, Dickinson College designed the "Crossing Borders" program to encourage culturally diverse students to live, work, and study together in multiple contexts both within the United States and abroad. Envisioning a series of crossings, the program brings together up to 20 students from Dickinson…

Cross-layer Energy Optimization Under Image Quality Constraints for Wireless Image Transmissions.

PubMed

Yang, Na; Demirkol, Ilker; Heinzelman, Wendi

2012-01-01

Wireless image transmission is critical in many applications, such as surveillance and environment monitoring. In order to make the best use of the limited energy of the battery-operated cameras, while satisfying the application-level image quality constraints, cross-layer design is critical. In this paper, we develop an image transmission model that allows the application layer (e.g., the user) to specify an image quality constraint, and optimizes the lower layer parameters of transmit power and packet length, to minimize the energy dissipation in image transmission over a given distance. The effectiveness of this approach is evaluated by applying the proposed energy optimization to a reference ZigBee system and a WiFi system, and also by comparing to an energy optimization study that does not consider any image quality constraint. Evaluations show that our scheme outperforms the default settings of the investigated commercial devices and saves a significant amount of energy at middle-to-large transmission distances.

Experimental and Numerical Study on Performance of Ducted Hydrokinetic Turbines with Pre-Swirl Stator Blades.

NASA Astrophysics Data System (ADS)

Gish, Andrew

2015-11-01

Ducts (also called shrouds) have been shown to improve performance of hydrokinetic turbines in some situations, bringing the power coefficient (Cp) closer to the Betz limit. Here we investigate optimization of the duct design as well as the addition of stator blades upstream of the turbine rotor to introduce pre-swirl in the flow. A small scale three-bladed turbine was tested in a towing tank. Three cases (bare turbine, with duct, and with duct and stators) were tested over a range of flow speeds. Important parameters include duct cross-sectional shape, blade-duct gap, stator cross-sectional shape, and stator angle. For each test, Cp was evaluated as a function of tip speed ratio (TSR). Experimental results were compared with numerical simulations. Results indicate that ducts and stators can improve performance at slower flow speeds and lower the stall speed compared to a bare turbine, but may degrade performance at higher speeds. Ongoing efforts to optimize duct and stator configurations will be discussed.

Net-aware bitstreams that upgrade FPGA hardware remotely over the Internet: creating intelligent bitstreams that know where to go, what to do when they get there, and can report back when they're done

NASA Astrophysics Data System (ADS)

Casselman, Steve; Schewel, John

2002-07-01

Success in the marketplace may well depend upon the ability to upgrade and test hardware designs instantly around the world. An upgrade management strategy requires more than just the bitstream file, email or a JTAG cable. A well-managed methodology, capable of transmitting bitstreams directly into targeted FPGAs over the network or internet is an essential element for a successful FPGA based product strategy. Virtual Computer Corporation"s HOTMan, Bitstream Management Environment combines a feature rich cross-platform API with an Object Oriented Bitstream technique for Remote Upgrading of Hardware over the Internet.

The effect of psychological stress on diet-induced thermogenesis and resting metabolic rate.

PubMed

Weststrate, J A; Van der Kooy, K; Deurenberg, P; Hautvast, J G

1990-04-01

The effect of psychological stress on resting metabolic rate (RMR) and diet-induced thermogenesis (DIT) was assessed in 12 healthy young non-obese men of body weight 70.2 +/- 1.2 kg (mean +/- s.e.m.) and age 25 +/- 0.6 years. Two types of commercially available motion pictures (video films) were shown to the subjects during the measurements, ie stress-inducing horror films and as a control, romantic family films. The study was conducted according to a cross-over design. RMR and respiratory quotients were not significantly influenced by the type of film shown to the subjects. DIT, assessed over 4 h, was significantly increased by the stress-inducing treatment, 0.95 +/- 0.05 kJ/min (mean +/- s.e.m.) versus 0.76 +/- 0.06 kJ/min (control). No significant effect was observed of psychological stress on postprandial substrate oxidation rates, nutrient balances, and urinary catecholamine excretion.

Natural convection enhancement by a discrete vibrating plate and a cross-flow opening: a numerical investigation

NASA Astrophysics Data System (ADS)

Florio, L. A.; Harnoy, A.

2011-06-01

In this study, a unique combination of a vibrating plate and a cross-flow passage is proposed as a means of enhancing natural convection cooling. The enhancement potential was estimated based on numerical studies involving a representative model which includes a short, transversely oscillating plate, placed over a transverse cross-flow opening in a uniformly heated vertical channel wall dividing two adjacent vertical channels. The resulting velocity and temperature fields are analyzed, with the focus on the local thermal effects near the opening. The simulation indicates up to a 50% enhancement in the local heat transfer coefficient for vibrating plate amplitudes of at least 30% of the mean clearance space and frequencies of over 82 rad/s.

Designing a biocompatible hydrogel for the delivery of mesalamine.

PubMed

Neufeld, Lena; Bianco-Peled, Havazelet

2015-08-01

A new design for nanocomposite hydrogels based on cross-linked chitosan for the delivery of mesalamine is presented. To enhance drug loading in chitosan, the mineral montmorillonite was incorporated into the matrix. The exfoliated silica montmorillonite nanosheets form interactions with both chitosan and mesalamine, which affect the hydrogel's drug release mechanism and swelling properties. The impact of montmorillonite and glutaraldehyde concentrations on the hydrogel properties was investigated. In vitro drug-release studies detected slower release over short times when montmorillonite was introduced into the matrix. This study is the first to evaluate the influence of pH during mixing and on mixing duration. It was shown that lowering the pH during mixing delayed the release since the positively charged drug was better introduced between the montmorillonite layers, as confirmed by differential scanning calorimetry (DSC) and fourier transform infrared spectroscopy (FTIR) analysis. All hydrogels showed prolonged sustained release of mesalamine over 24h in simulated colonic fluid (pH 7.4). When modeled, the mesalamine release profile suggests a complex release mechanism, involving adsorption of the drug to the montmorillonite and its diffusion. The results imply that chitosan-montmorillonite hydrogels can serve as potential drug carriers for controlled-release applications. Copyright © 2015 Elsevier B.V. All rights reserved.

Cross-Cultural Pedagogy: Practical Strategies for a Successful Interprofessional Study Abroad Course

ERIC Educational Resources Information Center

Bai, Jieru; Larimer, Susan; Riner, Mary Beth

2016-01-01

This article discusses some practical strategies for designing and implementing a cross-cultural interprofessional study abroad course, including pre-departure preparation, facilitating small groups with local students, establishing a weekly theme, utilizing role-play and reflective assignments, and implementing meaningful evaluation strategies.…

Biomarkers Predicting Progression of Human Immunodeficiency Virus-Related Disease

PubMed Central

Kanekar, Amar

2010-01-01

Biomarkers in predicting the progression of HIV infected individuals to a state of HIV disease (AIDS) are studied over more than a decade. Use of surrogate markers in the past for tracking clinical progression of the disease was limited, as little knowledge existed about the disease. The aim of this review was to address various changes in biomarker related studies taking place over the last five years, especially the trend towards use of newer biomarkers and experimentation with novel molecules in a quest for halting HIV disease progression. An open search of PUBMED database was made with search 'key words' such as 'Biomarkers' and 'AIDS (Acquired Immunodeficiency Syndrome)'.The following were the inclusion criteria for articles: a) all articles published in English language, b) years of publication between 2002-2008 and c) articles limited to adult population. This yielded a total of 417 articles. The criteria used for further judging these studies considered a) type of research design, b) number of biomarkers studied, c) validity of the biomarkers, d) techniques to assess the biomarkers and the impact of the studies in furthering biomarker research, e) sample size for the studies and f) article title or abstracts having the following key words 'biomarker' or 'biomarkers' and 'predict progression to AIDS'. A total of 27 abstracts were reviewed and 12 studies met the above criteria. These 12 different studies consisted of three reviews, four cohort designs, three cross-sectional designs, one each of an observational, and an in-vitro design. The various biomarkers emerging as a results were primarily a mix of viral, neural, immunological, HLA (human leukocyte antigen) markers along with lymphocyte counts. Although there have been quite a few advancements in biomarker-related studies, majority of the novel biomarkers discovered need to be further evaluated and replicated in bigger, long-term efficacy trials. Efforts should also be made to discover newer genetic markers of disease progression. Biomarker feedback, a new concept, can be utilized in future studies addressing prevention of HIV infection or halting disease progression. Keywords Biomarkers; Progression; Designs; HIV; AIDS; Validity PMID:21811520

Modeling and design of optimal flow perfusion bioreactors for tissue engineering applications.

PubMed

Hidalgo-Bastida, L Araida; Thirunavukkarasu, Sundaramoorthy; Griffiths, Sarah; Cartmell, Sarah H; Naire, Shailesh

2012-04-01

Perfusion bioreactors have been used in different tissue engineering applications because of their consistent distribution of nutrients and flow-induced shear stress within the tissue-engineering scaffold. A widely used configuration uses a scaffold with a circular cross-section enclosed within a cylindrical chamber and inlet and outlet pipes which are connected to the chamber on either side through which media is continuously circulated. However, fluid-flow experiments and simulations have shown that the majority of the flow perfuses through the center. This pattern creates stagnant zones in the peripheral regions as well as in those of high flow rate near the inlet and outlet. This non-uniformity of flow and shear stress, owing to a circular design, results in limited cell proliferation and differentiation in these areas. The focus of this communication is to design an optimized perfusion system using computational fluid dynamics as a mathematical tool to overcome the time-consuming trial and error experimental method. We compared the flow within a circular and a rectangular bioreactor system. Flow simulations within the rectangular bioreactor are shown to overcome the limitations in the circular design. This communication challenges the circular cross-section bioreactor configuration paradigm and provides proof of the advantages of the new design over the existing one. Copyright © 2011 Wiley Periodicals, Inc.

Smoking Behavior and Exposure: Results of a Menthol Cigarette Cross-over Study.

PubMed

Watson, Christina Vaughan; Richter, Patricia; de Castro, B Rey; Sosnoff, Connie; Potts, Jennifer; Clark, Pamela; McCraw, Joan; Yan, Xizheng; Chambers, David; Watson, Clifford

2017-05-01

Our objective was to improve understanding of the differences in use behavior and exposure when smoking menthol and non-menthol cigarettes using a 2-part cross-over design. Adult daily smokers were assigned randomly to alternate between 2 weeks of exclusively smoking a menthol test cigarette or a non-menthol test cigarette. Urine and saliva were collected for biomarker measurements; carbon monoxide (CO) was measured, and participants smoked test cigarettes through a CreSS® smoking topography device during 3 clinic visits. Participants turned in their cigarette butts from the test periods for determination of mouth level nicotine and completed subjective questionnaires related to the test cigarettes. Regardless of cigarette preference, participants had higher salivary cotinine when smoking the non-menthol test cigarette, but there were no significant differences detected in urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol between the 2 test cigarettes. Mouth level nicotine, puff volume, and puff duration were significantly higher when smoking the menthol brand. Both menthol and non-menthol smokers reported significantly lower enjoyment and satisfaction scores for test cigarettes compared with their brand of choice. Our results suggest that mentholation has an effect on measures of smoking behavior and that mouth level nicotine is a useful indicator of between-brand smoke exposure.

A novel way to detect correlations on multi-time scales, with temporal evolution and for multi-variables

NASA Astrophysics Data System (ADS)

Yuan, Naiming; Xoplaki, Elena; Zhu, Congwen; Luterbacher, Juerg

2016-06-01

In this paper, two new methods, Temporal evolution of Detrended Cross-Correlation Analysis (TDCCA) and Temporal evolution of Detrended Partial-Cross-Correlation Analysis (TDPCCA), are proposed by generalizing DCCA and DPCCA. Applying TDCCA/TDPCCA, it is possible to study correlations on multi-time scales and over different periods. To illustrate their properties, we used two climatological examples: i) Global Sea Level (GSL) versus North Atlantic Oscillation (NAO); and ii) Summer Rainfall over Yangtze River (SRYR) versus previous winter Pacific Decadal Oscillation (PDO). We find significant correlations between GSL and NAO on time scales of 60 to 140 years, but the correlations are non-significant between 1865-1875. As for SRYR and PDO, significant correlations are found on time scales of 30 to 35 years, but the correlations are more pronounced during the recent 30 years. By combining TDCCA/TDPCCA and DCCA/DPCCA, we proposed a new correlation-detection system, which compared to traditional methods, can objectively show how two time series are related (on which time scale, during which time period). These are important not only for diagnosis of complex system, but also for better designs of prediction models. Therefore, the new methods offer new opportunities for applications in natural sciences, such as ecology, economy, sociology and other research fields.

Radio Wave Propagation over Salem

NASA Astrophysics Data System (ADS)

Jaiswal, R. S.; Uma, S.; Raj, M. V. A.

2007-07-01

In this paper study of rainfall has been carried out over Salem, a place in Southern India. Rainfall rate values have been recorded using a fast response rain gauge installed at Sona College of Technology. The derived rainfall rates have been used to estimate attenuation in the 10-100 GHz frequency range. Using the estimated co-polar attenuation cross polar discriminations (XPD) have been computed using ITU-R(2002) model in the 10-35 GHz range. The study shows that attenuation and cross polarization vary with frequency, elevation angle and rainfall rate. The study also depicts the cumulative distribution of rainfall rate, attenuation and XPD.

CFD analysis of the two-phase bubbly flow characteristics in helically coiled rectangular and circular tube heat exchangers

NASA Astrophysics Data System (ADS)

Hussain, Alamin; Fsadni, Andrew M.

2016-03-01

Due to their ease of manufacture, high heat transfer efficiency and compact design, helically coiled heat exchangers are increasingly being adopted in a number of industries. The higher heat transfer efficiency over straight pipes is due to the secondary flow that develops as a result of the centrifugal force. In spite of the widespread use of helically coiled heat exchangers, and the presence of bubbly two-phase flow in a number of systems, very few studies have investigated the resultant flow characteristics. This paper will therefore present the results of CFD simulations for the two-phase bubbly flow in helically coiled heat exchangers as a function of the volumetric void fraction and the tube cross-section design. The CFD results are compared to the scarce flow visualisation experimental results available in the open literature.

Cross-sector surveys assessing perceptions of key stakeholders towards barriers, concerns and facilitators to the appropriate use of adaptive designs in confirmatory trials.

PubMed

Dimairo, Munyaradzi; Julious, Steven A; Todd, Susan; Nicholl, Jonathan P; Boote, Jonathan

2015-12-23

Appropriately conducted adaptive designs (ADs) offer many potential advantages over conventional trials. They make better use of accruing data, potentially saving time, trial participants, and limited resources compared to conventional, fixed sample size designs. However, one can argue that ADs are not implemented as often as they should be, particularly in publicly funded confirmatory trials. This study explored barriers, concerns, and potential facilitators to the appropriate use of ADs in confirmatory trials among key stakeholders. We conducted three cross-sectional, online parallel surveys between November 2014 and January 2015. The surveys were based upon findings drawn from in-depth interviews of key research stakeholders, predominantly in the UK, and targeted Clinical Trials Units (CTUs), public funders, and private sector organisations. Response rates were as follows: 30(55 %) UK CTUs, 17(68 %) private sector, and 86(41 %) public funders. A Rating Scale Model was used to rank barriers and concerns in order of perceived importance for prioritisation. Top-ranked barriers included the lack of bridge funding accessible to UK CTUs to support the design of ADs, limited practical implementation knowledge, preference for traditional mainstream designs, difficulties in marketing ADs to key stakeholders, time constraints to support ADs relative to competing priorities, lack of applied training, and insufficient access to case studies of undertaken ADs to facilitate practical learning and successful implementation. Associated practical complexities and inadequate data management infrastructure to support ADs were reported as more pronounced in the private sector. For funders of public research, the inadequate description of the rationale, scope, and decision-making criteria to guide the planned AD in grant proposals by researchers were all viewed as major obstacles. There are still persistent and important perceptions of individual and organisational obstacles hampering the use of ADs in confirmatory trials research. Stakeholder perceptions about barriers are largely consistent across sectors, with a few exceptions that reflect differences in organisations' funding structures, experiences and characterisation of study interventions. Most barriers appear connected to a lack of practical implementation knowledge and applied training, and limited access to case studies to facilitate practical learning.

A time projection chamber for high accuracy and precision fission cross-section measurements

DOE PAGES

Heffner, M.; Asner, D. M.; Baker, R. G.; ...

2014-05-22

The fission Time Projection Chamber (fissionTPC) is a compact (15 cm diameter) two-chamber MICROMEGAS TPC designed to make precision cross-section measurements of neutron-induced fission. The actinide targets are placed on the central cathode and irradiated with a neutron beam that passes axially through the TPC inducing fission in the target. The 4π acceptance for fission fragments and complete charged particle track reconstruction are powerful features of the fissionTPC which will be used to measure fission cross-sections and examine the associated systematic errors. This study provides a detailed description of the design requirements, the design solutions, and the initial performance ofmore » the fissionTPC.« less

Cross-over endocytosis of claudins is mediated by interactions via their extracellular loops.

PubMed

Gehne, Nora; Lamik, Agathe; Lehmann, Martin; Haseloff, Reiner F; Andjelkovic, Anuska V; Blasig, Ingolf E

2017-01-01

Claudins (Cldns) are transmembrane tight junction (TJ) proteins that paracellularly seal endo- and epithelial barriers by their interactions within the TJs. However, the mechanisms allowing TJ remodeling while maintaining barrier integrity are largely unknown. Cldns and occludin are heterophilically and homophilically cross-over endocytosed into neighboring cells in large, double membrane vesicles. Super-resolution microscopy confirmed the presence of Cldns in these vesicles and revealed a distinct separation of Cldns derived from opposing cells within cross-over endocytosed vesicles. Colocalization of cross-over endocytosed Cldn with the autophagosome markers as well as inhibition of autophagosome biogenesis verified involvement of the autophagosomal pathway. Accordingly, cross-over endocytosed Cldns underwent lysosomal degradation as indicated by lysosome markers. Cross-over endocytosis of Cldn5 depended on clathrin and caveolin pathways but not on dynamin. Cross-over endocytosis also depended on Cldn-Cldn-interactions. Amino acid substitutions in the second extracellular loop of Cldn5 (F147A, Q156E) caused impaired cis- and trans-interaction, as well as diminished cross-over endocytosis. Moreover, F147A exhibited an increased mobility in the membrane, while Q156E was not as mobile but enhanced the paracellular permeability. In conclusion, the endocytosis of TJ proteins depends on their ability to interact strongly with each other in cis and trans, and the mobility of Cldns in the membrane is not necessarily an indicator of barrier permeability. TJ-remodeling via cross-over endocytosis represents a general mechanism for the degradation of transmembrane proteins in cell-cell contacts and directly links junctional membrane turnover to autophagy.

[IBEAS design: adverse events prevalence in Latin American hospitals].

PubMed

Aranaz-Andrés, J M; Aibar-Remón, C; Limón-Ramírez, R; Amarilla, A; Restrepo, F R; Urroz, O; Sarabia, O; Inga, R; Santivañez, A; Gonseth-García, J; Larizgoitia-Jauregui, I; Agra-Varela, Y; Terol-García, E

2011-01-01

To describe the methodological characteristics of the IBEAS study: adverse events prevalence in Latin American hospitals, with the aim of analysing the magnitude, significance and impact of adverse events (AE); to identify the main problems associated with patient safety AE; to increase the capacity of professionals involved in patient safety; and the setting up of patient safety agendas in the participating countries. A patient safety study launched in 35 Latin American hospitals through the analysis of AE in 5 countries: Argentina, Colombia, Costa Rica, Mexico and Peru, using a cross-sectional study using a review of clinical records as the main method. The implications of using a cross-sectional design when studying AE are described, in terms of resources required, internal validity and usefulness related to risk management. The cross-sectional design seems an efficient methodology in terms of time and resources spent, as well as being easy to carry out. Although the cross-sectional design does not review the all hospital episodes, it is able to provide a reliable estimate of prevalence and to support a surveillance system. Because of a possible survival bias, it is likely that the AE which led to hospital admissions will be overestimated, as well as the health related infections or those adverse events which are difficult to identify if the patient is not examined (e.g. contusions). Communication with the ward staff (if the patient is still hospitalised) help in finding the causality and their prevention. Copyright © 2010 SECA. Published by Elsevier Espana. All rights reserved.

Minimalist design of water-soluble cross-[beta] architecture

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

Biancalana, Matthew; Makabe, Koki; Koide, Shohei

Demonstrated successes of protein design and engineering suggest significant potential to produce diverse protein architectures and assemblies beyond those found in nature. Here, we describe a new class of synthetic protein architecture through the successful design and atomic structures of water-soluble cross-{beta} proteins. The cross-{beta} motif is formed from the lamination of successive {beta}-sheet layers, and it is abundantly observed in the core of insoluble amyloid fibrils associated with protein-misfolding diseases. Despite its prominence, cross-{beta} has been designed only in the context of insoluble aggregates of peptides or proteins. Cross-{beta}'s recalcitrance to protein engineering and conspicuous absence among the knownmore » atomic structures of natural proteins thus makes it a challenging target for design in a water-soluble form. Through comparative analysis of the cross-{beta} structures of fibril-forming peptides, we identified rows of hydrophobic residues ('ladders') running across {beta}-strands of each {beta}-sheet layer as a minimal component of the cross-{beta} motif. Grafting a single ladder of hydrophobic residues designed from the Alzheimer's amyloid-{beta} peptide onto a large {beta}-sheet protein formed a dimeric protein with a cross-{beta} architecture that remained water-soluble, as revealed by solution analysis and x-ray crystal structures. These results demonstrate that the cross-{beta} motif is a stable architecture in water-soluble polypeptides and can be readily designed. Our results provide a new route for accessing the cross-{beta} structure and expanding the scope of protein design.« less

Minimalist design of water-soluble cross-beta architecture.

PubMed

Biancalana, Matthew; Makabe, Koki; Koide, Shohei

2010-02-23

Demonstrated successes of protein design and engineering suggest significant potential to produce diverse protein architectures and assemblies beyond those found in nature. Here, we describe a new class of synthetic protein architecture through the successful design and atomic structures of water-soluble cross-beta proteins. The cross-beta motif is formed from the lamination of successive beta-sheet layers, and it is abundantly observed in the core of insoluble amyloid fibrils associated with protein-misfolding diseases. Despite its prominence, cross-beta has been designed only in the context of insoluble aggregates of peptides or proteins. Cross-beta's recalcitrance to protein engineering and conspicuous absence among the known atomic structures of natural proteins thus makes it a challenging target for design in a water-soluble form. Through comparative analysis of the cross-beta structures of fibril-forming peptides, we identified rows of hydrophobic residues ("ladders") running across beta-strands of each beta-sheet layer as a minimal component of the cross-beta motif. Grafting a single ladder of hydrophobic residues designed from the Alzheimer's amyloid-beta peptide onto a large beta-sheet protein formed a dimeric protein with a cross-beta architecture that remained water-soluble, as revealed by solution analysis and x-ray crystal structures. These results demonstrate that the cross-beta motif is a stable architecture in water-soluble polypeptides and can be readily designed. Our results provide a new route for accessing the cross-beta structure and expanding the scope of protein design.

Examining Development of Curriculum Knowledge of Prospective Mathematics Teachers

ERIC Educational Resources Information Center

Sahin, Ömer; Soylu, Yasin

2017-01-01

Explanatory-confirmatory research design, one of the mixed methods research designs, was used in this study to investigate Curriculum Knowledge developments of prospective teachers regarding algebra. Cross-sectional study method, as a type of descriptive research and one of the non-experimental research designs, was used to collect quantitative…

Priority issues, study designs and geographical distribution in nutrition journals.

PubMed

Ortiz-Moncada, R; González-Zapata, L; Ruiz-Cantero, M T; Clemente-Gómez, V

2011-01-01

The increased number of articles published in nutrition is a reflection of the relevance to scientific community. The characteristics and quality of nutritional studies determine whether readers can obtain valid conclusions from them, as well as their usefulness for evidence-based strategic policies. To determine the characteristics of papers published in nutrition journals. Descriptive study design. We reviewed 330 original papers published between January-June 2007. From: American Journal of Clinical Nutrition (AJCN), Journal of Nutrition, European Journal Nutrition, European Journal of Clinical Nutrition and Public Health Nutrition. We classified them according to the subjects studied; risk factors, study design and country of origin. Almost half the papers studied healthy people (53.3%). The most frequent illness was obesity (13.9%). Food consumption is the most frequent risk factor (63.3%). Social factors appear exclusively only in 3.6% of the papers. Clinical trials were the most common analytical design (31.8%), mainly in the AJCN (45.6%). Cross-sectional studies were the most frequent type of observational design (37.9%). Ten countries produced over half of the papers (51.3%). The US publishes the highest number of papers (20.6%), whilst developing countries make only scarce contributions to scientific literature on nutrition. Most of the papers had inferential power. They generally studied both healthy and sick subjects, coinciding with the aims of international scientific policies. However, the topics covered reflect a clear bias, prioritizing problems pertaining to developed countries. Social determinants of health should also be considered, along with behavioral and biological risk factors.

Respiratory-Induced Haemodynamic Changes: A Contributing Factor to IVC Filter Penetration

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

Laborda, Alicia, E-mail: alaborda@unizar.es; Kuo, William T., E-mail: wkuo@stanford.edu; Ioakeim, Ignatios, E-mail: ignacio.ioakim@hotmail.es

2015-10-15

PurposeThe purpose of the study is to evaluate the influence of respiratory-induced vena caval hemodynamic changes on filter migration/penetration.Materials and MethodsAfter placement of either a Gunther Tulip or Celect IVC filter, 101 consecutive patients scheduled for filter retrieval were prospectively enrolled in this study. Pre-retrieval CT scans were used to assess filter complications and to calculate cross-sectional area in three locations: at level of filter strut fixation, 3 cm above and 3 cm below. A 3D finite element simulation was constructed on these data and direct IVC pressure was recorded during filter retrieval. Cross-sectional areas and pressures of the vena cava weremore » measured during neutral breathing and in Valsalva maneuver and identified filter complications were recorded. A statistical analysis of these variables was then performed.ResultsDuring Valsalva maneuvers, a 60 % decrease of the IVC cross-sectional area and a fivefold increase in the IVC pressure were identified (p < 0.001). There was a statistically significant difference in the reduction of the cross-sectional area at the filter strut level (p < 0.001) in patient with filter penetration. Difficulty in filter retrieval was higher in penetrated or tilted filters (p < 0.001; p = 0.005). 3D computational models showed significant IVC deformation around the filter during Valsalva maneuver.ConclusionCaval morphology and hemodynamics are clearly affected by Valsalva maneuvers. A physiological reduction of IVC cross-sectional area is associated with higher risk of filter penetration, despite short dwell times. Physiologic data should be used to improve future filter designs to remain safely implanted over longer dwell times.« less

Anticipating market demand: tracking enrollee satisfaction and health over time.

PubMed

Allen, H

1998-12-01

To assess guidelines, set by the National Committee for Quality Assurance, for the Health Plan Employer Data and Information Set (HEDIS) 1999 CAHPS 2.0H Survey (formerly the HEDIS 1999 Consumer Survey) in the light of user's needs to monitor health plan performance over time, monitor sick enrollees, and prioritize determinants (drivers) of enrollee experience. A two-wave, cross-sectional/longitudinal panel design, consisting of national surveys mailed to employees of three major USA corporations in 1993 and 1995. Samples included employees selected to represent 23 major managed care and indemnity plans in five regions of the USA. In 1993, 14 587 employees responded and in 1995 9018 employees responded (response rates: 51 and 52%). The longitudinal panel sample included 5729 employees who completed both surveys and stayed in the same plan for both years. STUDY MEASURES: The main 1993 and 1995 surveys consisted of 154 and 116 items, respectively. Panel survey content assessed care delivery, plan administration, functional status, well being, and chronic disease. CAHPS 2.0H's point-in-time, cross-sectional design was unable to detect selection bias and led to an inaccurate view of change in performance. CAHPS 2.0H's use of aggregate samples masked key differences between healthy and sick enrollees; e.g. the sick became less satisfied over time. The association-based, statistical techniques that many survey users will employ to prioritize the 'drivers' of enrollee experience in the absence of CAHPS 2.0H guidelines yielded a less efficient account of change than the multi-method/multi-trait approach developed for this project. Consumer experience of plan performance is best understood when the separate contributions of longitudinal membership and movement in and out of plans are clarified, changes in health are identified, changes for sick and healthy enrollees are compared, and plan performance on satisfaction criteria is probed to give confirmation and detail. Changes to the CAHPS 2.0H approach in HEDIS 1999 will facilitate user application of these principles.

Perspectives on Highly Adaptive or Morphing Aircraft

NASA Technical Reports Server (NTRS)

McGowan, Anna-Maria R.; Vicroy, Dan D.; Busan, Ronald C.; Hahn, Andrew S.

2009-01-01

The ability to adapt to different flight conditions has been fundamental to aircraft design since the Wright Brothers first flight. Over a hundred years later, unconventional aircraft adaptability, often called aircraft morphing has become a topic of considerable renewed interest. In the past two decades, this interest has been largely fuelled by advancements in multi-functional or smart materials and structures. However, highly adaptive or morphing aircraft is certainly a cross-discipline challenge that stimulates a wide range of design possibilities. This paper will review some of the history of morphing aircraft including recent research programs and discuss some perspectives on this work.

Experimental Aeroheating Study of Mid-L/D Entry Vehicle Geometries: NASA LaRC 20-Inch Mach 6 Air Tunnel Test 6966

NASA Technical Reports Server (NTRS)

Hollis, Brian R.; Hollingsworth, Kevin E.

2014-01-01

Aeroheating data on mid lift-to-drag ratio entry vehicle configurations has been obtained through hypersonic wind tunnel testing. Vehicles of this class have been proposed for high-mass Mars missions, such as sample return and crewed exploration, for which the conventional sphere-cone entry vehicle geometries of previous Mars missions are insufficient. Several configurations were investigated, including elliptically-blunted cylinders with both circular and elliptical cross sections, biconic geometries based on launch vehicle dual-use shrouds, and parametrically-optimized analytic geometries. Testing was conducted at Mach 6 over a range of Reynolds numbers sufficient to generate laminar, transitional, and turbulent flow. Global aeroheating data were obtained using phosphor thermography. Both stream-wise and cross-flow transition occured on different configurations. Comparisons were made with laminar and turbulent computational predictions generated with an algebraic turbulence model. Predictions were generally in good agreement in regions of laminar or fully-turbulent flow; however for transitional cases, the lack of a transition onset prediction capability produced less accurate comparisons. The data obtained in this study are intended to be used for prelimary mission design studies and the development and validation of computational methods.

Multinational Corporations, Democracy and Child Mortality: A Quantitative, Cross-National Analysis of Developing Countries

ERIC Educational Resources Information Center

Shandra, John M.; Nobles, Jenna E.; London, Bruce; Williamson, John B.

2005-01-01

This study presents quantitative, sociological models designed to account for cross-national variation in child mortality. We consider variables linked to five different theoretical perspectives that include the economic modernization, social modernization, political modernization, ecological-evolutionary, and dependency perspectives. The study is…

Psychological effects of (S)-ketamine and N,N-dimethyltryptamine (DMT): a double-blind, cross-over study in healthy volunteers.

PubMed

Gouzoulis-Mayfrank, E; Heekeren, K; Neukirch, A; Stoll, M; Stock, C; Obradovic, M; Kovar, K-A

2005-11-01

Pharmacological challenges with hallucinogens are used as models for psychosis in experimental research. The state induced by glutamate antagonists such as phencyclidine (PCP) is often considered as a more appropriate model of psychosis than the state induced by serotonergic hallucinogens such as lysergic acid diethylamide (LSD), psilocybin and N,N-dimethyltryptamine (DMT). However, so far, the psychological profiles of the two types of hallucinogenic drugs have never been studied directly in an experimental within-subject design. Fifteen healthy volunteers were included in a double-blind, cross-over study with two doses of the serotonin 5-HT2A agonist DMT and the glutamate N-methyl-D-aspartate (NMDA) antagonist (S)-ketamine. Data are reported for nine subjects who completed both experimental days with both doses of the two drugs. The intensity of global psychological effects was similar for DMT and (S)-ketamine. However, phenomena resembling positive symptoms of schizophrenia, particularly positive formal thought disorder and inappropriate affect, were stronger after DMT. Phenomena resembling negative symptoms of schizophrenia, attention deficits, body perception disturbances and catatonia-like motor phenomena were stronger after (S)-ketamine. The present study suggests that the NMDA antagonist model of psychosis is not overall superior to the serotonin 5-HT2A agonist model. Rather, the two classes of drugs tend to model different aspects or types of schizophrenia. The NMDA antagonist state may be an appropriate model for psychoses with prominent negative and possibly also catatonic features, while the 5-HT2A agonist state may be a better model for psychoses of the paranoid type.

Pedestrian Safety in Road Traffic in Poland

NASA Astrophysics Data System (ADS)

Budzynski, Marcin; Jamroz, Kazimierz; Mackun, Tomasz

2017-10-01

Every third road accident in Poland involves a pedestrian as a participant or, most of the time, a casualty. Pedestrian accidents are usually the result of complex situations and the outcome of a number of factors related to driver and pedestrian behaviour and road infrastructure. Safety depends largely on how well the traffic condition is perceived and on visibility in traffic. The paper presents the results of analyses of methodologies for systematic studies of pedestrian behaviour and pedestrian-driver relations. The effects of the location of the site, type of cross-section and other selected parameters on pedestrian and driver behaviour are demonstrated. The analyses showed that pedestrians are most often put at risk by too long pedestrian crossings, vehicles going too fast around pedestrian crossings, lack of proper sight distance and poorly lit or unlit pedestrian crossings. The reason for such defective infrastructure is that planners, designers, contractors and maintenance services are not receiving any support from design, marking and maintenance regulations for pedestrian traffic. In addition, the Road Traffic Law is not restrictive enough when it comes to drivers’ obligations towards pedestrian safety. Polish design regulations allow long pedestrian crossings up to four lanes in one direction or three lanes in two directions irrespective of traffic control and speed limits. Pedestrian crossings should be kept at a maximum of three lanes. There is nothing in the design regulations about the required driver-pedestrian sight distance. Neither does the Road Traffic Law help engineers with that. It is legal to park vehicles within 10 m of a pedestrian crossing which does not guarantee the necessary sight distance. Drivers must be able to see a pedestrian waiting or stepping onto the crossing from a distance that will help them come to a stop safely. It is safer to follow the principle of providing adequate pedestrian sight distance. Recommendations for pedestrian crossing design are also provided.

Polarimetric Measurements Over the Sea-Surface with the Airborne STORM Radar in the Context of the Geophysical Validation of the ENVISAT ASAR

NASA Astrophysics Data System (ADS)

Podvin, D. Hauser. T.; Dechambre, M.; Valentin, R.; Caudal, G.; Daloze, J.-F.; Mouche, A.

2003-04-01

Among the new specificities of the ENVISAT/ASAR particular polarization diversity make the instrument very promising, but require complementary studies in addition to those already completed with the ERS data. Moreover, in the context of the preparation of other missions which will embark polarimetric SAR (e.g. RADARSAT2) it is important to better assess the benefit of multi-polarization or polarimetric SAR systems. In particular, over the ocean the question remains open regarding the estimate of wind speed, directional spectra of surface ocean waves and maybe other parameters related to wave breaking. CETP has designed and developed a new airborne radar called STORM], which has a full polarimetric capability. STORM is a new-version of the RESSAC airborne radar already used in previous experiments (Hauser et al, JGR 1992). STORM is a real-aperture, C-Band system with a FM/CW transmission and with a rotating antenna to explore in azimuth. In addition to RESSAC (which was mono-polarized) it offers a polarization diversity (receiving simultaneously in H and V polarizations) which enables us to analyze the radar cross- section in HH, VV, HV, and other cross-polarized terms related to the scattering matrix. In the context of the validation of the ASAR wave mode of ENVISAT, a field experiment will be carried out in October and November 2002 over the ocean (offshore the coasts of Brittany, France), with STORM] embarked on the MERLIN-IV aircraft of Meteo-France. We intend to perform about 20 flights under the ENVISAT SAR swath during a one-month experiment, with overpasses over a directional wave buoy also equipped with wind measurements. The ASAR image mode (in HH or VV) or alternating polarization mode will be requested during these flights. STORM will be used in a mode which will permit to measure the full complex scattering matrix over the sea surface at incidence angles ranging from 10 to 35°. In addition to conventional analysis of the radar cross-sections in HH, and VV polarizations to estimate wind speed and directional wave spectra, cross-polarized cross-sections and parameters derived from the full polarimetric matrix will be analyzed to investigate their relation with the environmental conditions (wind, waves), using co-located in situ measurements. With this combination of measurements we will first assess the performance of the ASAR products and inversion scheme to estimate the 2D wave spectra and wind in various configurations of polarization state. In addition, we expect new results on the parameters related to the full polarimetric matrix and their relation with environmental conditions. During this workshop, first results of this experiment will be presented.

Beyond Borders: Participatory Design Research and the Changing Role of Design

ERIC Educational Resources Information Center

Blair-Early, Adream

2010-01-01

University art and design programs are branching out and creating cross-disciplinary programs and research centers that connect design students and faculty across various disciplines such as business, engineering, architecture, information studies, health sciences and education. A human-centered, problem-based approach to design research looks to…

Pressure and heating-rate distributions on a corrugated surface in a supersonic turbulent boundary layer

NASA Technical Reports Server (NTRS)

Sawyer, J. W.

1977-01-01

Drag and heating rates on wavy surfaces typical of current corrugated plate designs for thermal protection systems were determined experimentally. Pressure-distribution, heating-rate, and oil-flow tests were conducted in the Langley Unitary Plan wind tunnel at Mach numbers of 2.4 and 4.5 with the corrugated surface exposed to both thick and thin turbulent boundary layers. Tests were conducted with the corrugations at cross-flow angles from 0 deg to 90 deg to the flow. Results show that for cross-flow angles of 30 deg or less, the pressure drag coefficients are less than the local flat-plate skin-friction coefficients and are not significantly affected by Mach number, Reynolds number, or boundary-layer thickness over the ranges investigated. For cross-flow angles greater than 30 deg, the drag coefficients increase significantly with cross-flow angle and moderately with Reynolds number. Increasing the Mach number causes a significant reduction in the pressure drag. The average and peak heating penalties due to the corrugated surface are small for cross-flow angles of 10 deg or less but are significantly higher for the larger cross-flow angles.

[Genetic control of mitotic crossing-over in yeasts. III. Induction by 8-methoxypsoralen and long-wave UV irradiation (lambda=365 nm)].

PubMed

Fedorova, I V; Marfin, S V

1982-02-01

The lethal effect of 8-methoxypsoralen (8-MOP) plus 365 nm light has been studied in haploid radiosensitive strains of Saccharomyces cerevisiae. The diploid of wild type and the diploid homozygous for the rad2 mutation (this mutation blocks the excision of UV-induced pyrimidine dimers) were more resistant to the lethal effect of 8-MOP plus 365 nm light than the haploid of wild type and rad2 haploid, respectively. The diploid homozygous for rad54 mutation (the mutation blocks the repair of double-strand breaks in DNA) was more sensitive than haploid rad54. The method of repeated irradiation allowed to study the capacity of radiosensitive diploids to remove monoadducts induced by 8-MOP in DNA. This process was very effective in diploids of wild type and in the rad54 rad54 diploid, while the rad2 rad2 diploid was characterized by nearly complete absence of monoadduct excision. The study of mitotic crossing over and mitotic segregation in yeast diploids, containing a pair of complementing alleles of the ade2 gene (red/pink) has shown a very high recombinogenic effect of 8-MOP plus 365 nm light. The rad2 mutation slightly increased the frequency of mitotic segregation and mitotic crossing over. The rad54 mutation decreased the frequency of mitotic segregation and entirely suppressed mitotic crossing over. The method of repeated irradiation showed that the cross-links, but not monoadducts, are the main cause of high recombinogenic effect of 8-MOP plus 365 nm light. The possible participation of different repair systems in recombinational processes induced by 8-MOP in yeast cells is discussed.

Susceptibility to depression expressed as alterations in cortisol day curve: a cross-twin, cross-trait study.

PubMed

Wichers, Marieke C; Myin-Germeys, Inez; Jacobs, Nele; Kenis, Gunter; Derom, Catherine; Vlietinck, Robert; Delespaul, Philippe; Mengelers, Ron; Peeters, Frenk; Nicolson, Nancy; Van Os, Jim

2008-04-01

To examine, using a cross-twin cross-trait design, the hypotheses 1) that the genetic and environmental susceptibility to depression is expressed, in part, as alterations in cortisol day curves and 2) that cortisol abnormalities are not merely the consequence of depressive states or the stressors associated with its onset. Alteration of diurnal secretion of cortisol is a possible endophenotype of depression, as depressed patients show alterations in cortisol dynamics over the day. Salivary cortisol measurements were obtained in a sample of 279 twin pairs at 10 random times a day for 5 days. A structured clinical interview for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th Edition) axis I mood disorder (SCID) was administered. Using multilevel regression analysis, the moderating influence of a lifetime diagnosis of depression in the co-twin on the association between time of day and cortisol concentrations in the proband twin was examined. Diurnal variation in cortisol in the proband twin differed as a function of lifetime diagnosis of depression in the co-twin. In addition, this moderating effect was significantly stronger for dizygotic than for monozygotic twins. Probands of co-twins with lifetime depression have a different diurnal cortisol profile than those without, suggesting that altered hypothalamic-pituitary-adrenal axis functioning is an indicator of depression susceptibility.

Treatment of asthma patients with herbal medicine TJ-96: a randomized controlled trial.

PubMed

Urata, Y; Yoshida, S; Irie, Y; Tanigawa, T; Amayasu, H; Nakabayashi, M; Akahori, K

2002-06-01

Alternative medicine use has increased at a remarkable pace all over the world in recent years. Although herbal medicine for the treatment of asthma is becoming the focus of public attention, randomized studies had not been performed, even in Eastern countries including Japan. This study was designed to investigate whether one of the Japanese government approved herbal complexes Saiboku-to (TJ-96) is effective for the treatment of atopic asthma, and to investigate whether this protective activity is associated with a reduction in eosinophilic inflammation. A double-blind, randomized, crossover design was used. Subjects received 2.5 g of TJ-96 or placebo orally 3 times daily for 4 weeks and then, after a washout period of at least 4 weeks, crossed over to receive the alternative treatment. We assessed the effects of pretreatment with TJ-96 on bronchoconstriction precipitated by inhalation of methacholine. Furthermore, eosinophil counts and measurement of eosinophilic cationic protein (ECP) were performed. After 4 weeks of treatment with TJ-96, values of PC20 -methacholine significantly improved in the treatment with TJ-96. Also, patients' symptoms, blood eosinophils, serum ECP, sputum eosinophils, and sputum ECP were significantly decreased. Our results suggest that TJ-96 has an antiinflammatory effect on bronchial eosinophilic infiltration. This study raises further interesting therapeutic possibilities and argues for further trials of new approaches to the treatment of asthma.

Annual Review of Asian American Psychology, 2014

PubMed Central

Kim, Su Yeong; Shen, Yishan; Hou, Yang; Tilton, Kelsey E.; Juang, Linda; Wang, Yijie

2015-01-01

This 2014 review of Asian American psychology is the sixth review in the series. It includes 316 articles that met the inclusion criteria established by the past five annual reviews. Featured articles were derived from three sources: 137 were generated via the search term “Asian American” in PyscINFO, 111 were generated via a search for specific Asian American ethnic groups, and 32 were generated via author searches of articles that met the inclusion criteria. The top primary topic was health and health-related behaviors, the most frequently employed study design was cross-sectional, and the most studied Asian American ethnic group was Chinese. This year’s review includes information on the target population of the primary topic, the age range and developmental period of participants, and whether the study design was cross-sectional or longitudinal. It also identifies top authors and journals contributing to the 2014 annual review. These new features reveal that the most common target population of the primary topic was youths; studies most commonly included emerging adults ages 18–25; cross-sectional study design was employed more often than longitudinal design; the top contributor to the 2014 review was Stephen Chen, who authored the highest number of papers included; and the Asian American Journal of Psychology generated the highest number of publications for this review. PMID:26925199

Truck freight crossing the Canada-U.S. border : an analysis of the cross-border component of the 1999 Canadian National Roadside Study

DOT National Transportation Integrated Search

2002-09-23

The United States and Canada are each others largest trading partner. Trade and traffic between the countries, especially by land transportation, has been increasing at a rapid rate over the past 25 years. This study, produced by the Eastern Border T...

AN ANALYSIS OF THE CROSS-CULTURAL STUDY OF CHILDREN'S SOCIAL BEHAVIOR, FINAL REPORT.

ERIC Educational Resources Information Center

LONGABAUGH, RICHARD

SYSTEMATICALLY OBSERVED, RECORDED, AND CODED INTERPERSONAL BEHAVIORS OF CHILDREN, AGES 3 TO 11, WERE EXAMINED FOR THE EXISTENCE OF CROSS-CULTURALLY CONSISTENT RELATIONS BETWEEN THEIR BEHAVIORS. THE STUDY SAMPLE CONSISTED OF OVER 130 CHILDREN FROM DIVERSE CULTURES, AND WAS SELECTED FROM COMMUNITIES IN NEW ENGLAND, MEXICO, AFRICA, INDIA, OKINAWA,…

Inflammatory response of a new synthetic dialyzer membrane. A randomised cross-over comparison between polysulfone and helixone.

PubMed

Stefoni, S; Colì, L; Cianciolo, G; Donati, G; Ruggeri, G; Ramazzotti, E; Pohlmeier, R; Lang, D

2003-01-01

Hemodialysis patients suffer from chronic inflammation due to intradialytic contact of blood with artificial materials. The FX 60 dialyzer which belongs to the new FX-class series of dialyzers is composed of the new membrane Helixone. This membrane is derived from the original Fresenius Polysulfone membrane. The FX-class design is based on modified geometry of fibres and housing and has resulted in a new dialyzer with improved efficiency, safety and ease of handling compared to the F series (F 60S) dialyzer. The aim of the study was to investigate whether the biocompatibility pattern in terms of inflammatory parameters of the new type of polysulfone dialyzer has changed compared to the standard. A clinical in vivo study was conducted to compare the intradialytic inflammatory response of the two dialyzers, FX 60 and F 60S. Eight chronic dialysis patients were selected for the study: mean age 65.5 +/- 15.5 years, mean time on dialysis 100 +/- 95 months. The randomized cross-over study involved a treatment period of 2 weeks (total 6 sessions), one week with each dialyzer, starting with one or the other according to the randomization scheme. Blood samples were taken at 0 (T0), 15, 60, and 240 minutes to evaluate white blood cell (WBC) count, complement factor C5a, leukocyte elastase, soluble intercellular adhesion molecule 1 (sICAM-1), platelet count, C-reactive protein (CRP). At 15 min, WBC count showed a comparably, low decrease for both dialyzers: -7.6% for FX 60 versus -6.6% for F 60S, p=not significant (ns). At the same time the C5a concentration decreased from 15.0 +/- 7.5 ng/ml to 13.5 +/- 6.7 ng/ml (p=ns) for FX 60, and from 15.1 +/- 12.5 ng/ml to 14.9 +/- 25.0 ng/ml for F 60S (p=ns). The elastase concentration progressively increased over time with no statistical difference between the two dialyzers. The levels of sICAM-1, CRP, and platelet count were similar at each time point for both dialyzers, varying around the baseline values (p=ns). No significant difference emerged in terms of inflammatory response between the two dialyzers, hemo demonstrating that the biocompatibility of the F-series was maintained in the FX-class series of dialyzers and is independent of design factors.

Plasma clearance of neostigmine and pyridostigmine in the dog.

PubMed Central

Baker, P R; Calvey, T N; Chan, K; Macnee, C M; Taylor, K

1978-01-01

1 The pharmacokinetics of neostigmine and pyridostigmine was studied in conscious dogs by the use of a cross-over design. 2 Both neostigmine and pyridostigmine were cleared from plasma in a biexponential manner. 3 The apparent volume of distribution of pyridostigmine was invariably greater than that of neostigmine, and its fast disposition half-life was approximately three times longer. 4 The whole body clearance and the urinary elimination of pyridostigmine was approximately twice that of neostigmine. 5 The slow disposition half-life of pyridostigmine was approximately three times longer than that of neostigmine, suggesting that the longer duration of action of pyridostigmine is related to the differential clearance of the two quarternary amines from plasma. PMID:667495

Terahertz broadband polarization converter based on metamaterials

NASA Astrophysics Data System (ADS)

Li, Yonghua; Zhao, Guozhong

2018-01-01

Based on the metamaterial composed of symmetrical split resonant ring, a broadband reflective terahertz polarization converter is proposed. The numerical simulation shows that it can rotate the polarization direction of linear polarized wave 90° in the range of 0.7-1.8THz and the polarization conversion ratio is over 90%. The reflection coefficient of the two electric field components in the diagonal direction is the same and the phase difference is 180° ,which leads to the cross-polarization rotation.In order to further study the physical mechanism of high polarization conversion, we analyze the surface current distribution of the resonant ring. The polarization converter has potential applications in terahertz wave plate and metamaterial antenna design.

Evaluation of Speech Perception via the Use of Hearing Loops and Telecoils

PubMed Central

Holmes, Alice E.; Kricos, Patricia B.; Gaeta, Laura; Martin, Sheridan

2015-01-01

A cross-sectional, experimental, and randomized repeated-measures design study was used to examine the objective and subjective value of telecoil and hearing loop systems. Word recognition and speech perception were tested in 12 older adult hearing aid users using the telecoil and microphone inputs in quiet and noise conditions. Participants were asked to subjectively rate cognitive listening effort and self-confidence for each condition. Significant improvement in speech perception with the telecoil over microphone input in both quiet and noise was found along with significantly less reported cognitive listening effort and high self-confidence. The use of telecoils with hearing aids should be recommended for older adults with hearing loss. PMID:28138458

National suicide rates a century after Durkheim: do we know enough to estimate error?

PubMed

Claassen, Cynthia A; Yip, Paul S; Corcoran, Paul; Bossarte, Robert M; Lawrence, Bruce A; Currier, Glenn W

2010-06-01

Durkheim's nineteenth-century analysis of national suicide rates dismissed prior concerns about mortality data fidelity. Over the intervening century, however, evidence documenting various types of error in suicide data has only mounted, and surprising levels of such error continue to be routinely uncovered. Yet the annual suicide rate remains the most widely used population-level suicide metric today. After reviewing the unique sources of bias incurred during stages of suicide data collection and concatenation, we propose a model designed to uniformly estimate error in future studies. A standardized method of error estimation uniformly applied to mortality data could produce data capable of promoting high quality analyses of cross-national research questions.

'Poor me' versus 'Bad me' paranoia: the association between self-beliefs and the instability of persecutory ideation.

PubMed

Melo, Sara Sigmaringa; Bentall, Richard P

2013-06-01

To investigate whether different self-attributes would be associated with different degrees of deservedness of persecution in a clinical paranoid sample. Some studies have shown differences between the self-esteem (SE) of individuals with 'Poor Me' (PM) and 'Bad Me' (BM) paranoia (Bentall et al., 2009; Chadwick, Trower, Juusti-Butler, & Maguire, 2005). Most studies investigating this relationship have employed a cross-sectional design, precluding the investigation of changes over time. In the cross-sectional part of the study, 45 clinical participants and 25 controls were assessed in terms of paranoia, deservedness of persecution, SE, self-discrepancies, daily events, and coping strategies. In the longitudinal part of the study, the clinical group was re-assessed over a period of another 2 days, in order to study changes in these variables. At baseline, there were no differences between the SE of the two paranoia presentations, which was significantly lower than the controls'. However, the paired-samples repeated analysis found the SE of individuals when in a PM presentation was higher than when they were BM. Only BM paranoia was found to be associated with higher self-ideal:self-actual self-discrepancies than the other groups. The longitudinal analysis indicated that, having been PM and having low SE at the previous assessment day made it more likely that individuals would be in BM subsequently. No differences in causal attributions made for ecological events were found between the groups. Higher SE was found to be more likely when individuals coped with adversities by using social support. Both deservedness of persecution and self-views appear to be unstable in individuals with paranoia and to change consistently over time, a finding which is in keeping with Bentall et al.'s (2001) dynamic model of paranoia. © 2012 The British Psychological Society.

Robust Crossfeed Design for Hovering Rotorcraft

NASA Technical Reports Server (NTRS)

Catapang, David R.

1993-01-01

Control law design for rotorcraft fly-by-wire systems normally attempts to decouple angular responses using fixed-gain crossfeeds. This approach can lead to poor decoupling over the frequency range of pilot inputs and increase the load on the feedback loops. In order to improve the decoupling performance, dynamic crossfeeds may be adopted. Moreover, because of the large changes that occur in rotorcraft dynamics due to small changes about the nominal design condition, especially for near-hovering flight, the crossfeed design must be 'robust'. A new low-order matching method is presented here to design robust crossfeed compensators for multi-input, multi-output (MIMO) systems. The technique identifies degrees-of-freedom that can be decoupled using crossfeeds, given an anticipated set of parameter variations for the range of flight conditions of concern. Cross-coupling is then reduced for degrees-of-freedom that can use crossfeed compensation by minimizing off-axis response magnitude average and variance. Results are presented for the analysis of pitch, roll, yaw and heave coupling of the UH-60 Black Hawk helicopter in near-hovering flight. Robust crossfeeds are designed that show significant improvement in decoupling performance and robustness over nominal, single design point, compensators. The design method and results are presented in an easily used graphical format that lends significant physical insight to the design procedure. This plant pre-compensation technique is an appropriate preliminary step to the design of robust feedback control laws for rotorcraft.

Surveying drainage culvert use by carnivores: sampling design and cost-benefit analyzes of track-pads vs. video-surveillance methods.

PubMed

Mateus, Ana Rita A; Grilo, Clara; Santos-Reis, Margarida

2011-10-01

Environmental assessment studies often evaluate the effectiveness of drainage culverts as habitat linkages for species, however, the efficiency of the sampling designs and the survey methods are not known. Our main goal was to estimate the most cost-effective monitoring method for sampling carnivore culvert using track-pads and video-surveillance. We estimated the most efficient (lower costs and high detection success) interval between visits (days) when using track-pads and also determined the advantages of using each method. In 2006, we selected two highways in southern Portugal and sampled 15 culverts over two 10-day sampling periods (spring and summer). Using the track-pad method, 90% of the animal tracks were detected using a 2-day interval between visits. We recorded a higher number of crossings for most species using video-surveillance (n = 129) when compared with the track-pad technique (n = 102); however, the detection ability using the video-surveillance method varied with type of structure and species. More crossings were detected in circular culverts (1 m and 1.5 m diameter) than in box culverts (2 m to 4 m width), likely because video cameras had a reduced vision coverage area. On the other hand, carnivore species with small feet such as the common genet Genetta genetta were detected less often using the track-pad surveying method. The cost-benefit analyzes shows that the track-pad technique is the most appropriate technique, but video-surveillance allows year-round surveys as well as the behavior response analyzes of species using crossing structures.

Emotion regulation difficulties as a prospective predictor of posttraumatic stress symptoms following a mass shooting.

PubMed

Bardeen, Joseph R; Kumpula, Mandy J; Orcutt, Holly K

2013-03-01

A strong positive association between emotion regulation difficulties (ERD) and posttraumatic stress symptoms (PTSS) has been consistently evidenced in cross-sectional research. However, a lack of prospective research has limited hypotheses regarding the temporal relationship between trauma exposure, ERD, and PTSS. The present prospective study investigated the role of pre-trauma difficulties with emotion regulation in the development of PTSS following exposure to a potentially traumatic event. Between Time 1 (T1) and Time 2 (T2), a mass shooting occurred at the participants' (n=691) university campus. ERD and PTSS were assessed prior to the shooting (T1), in the acute aftermath of the shooting (T2), and approximately eight months later (T3). Using a cross-lagged panel design, ERD was found to prospectively predict PTSS from T1 to T2 and T2 to T3. Additionally, PTSS prospectively predicted ERD from T1 to T2. However, T2 PTSS failed to predict T3 PTSS. Results indicate that ERD and PTSS are reciprocally influential from pre- to post-shooting. Further, results suggest that emotion dysregulation in the aftermath of a potentially traumatic event influences one's ability to recover from PTSS over time, even after accounting for the effects of existing symptomatology. To examine the specificity of temporal relations between ERD and PTSS a second cross-lagged panel design, in which a general distress construct was substituted for PTSS, was conducted. Results of this analysis, as well as conceptual and clinical implications, will be discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Providing Academic Leadership in Universities in Cross River State, Nigeria: Assessment of Departmental Heads' Effectiveness

ERIC Educational Resources Information Center

Akuegwu, Basil A.; Nwi-ue, Felix D.

2017-01-01

This study assessed Heads of Departments' effectiveness in providing academic leadership at the departmental level. I research question and 2 hypotheses were formulated to give direction to this investigation. Survey design was adopted for the study. The population of the study comprised 110 Heads of Departments from 2 universities in Cross River…

Adolescent Idiopathic Scoliosis and Eating Disorders: Is There a Relation? Results of a Cross-Sectional Study

ERIC Educational Resources Information Center

Zaina, Fabio; Donzelli, Sabrina; Lusini, Monia; Vismara, Luca; Capodaglio, Paolo; Neri, Laura; Negrini, Stefano

2013-01-01

A recent study suggests a correlation between idiopathic scoliosis in adolescence and eating disorders. However, this does not correspond with our clinical experience in the same population. The aim of this study was to verify the correlation between scoliosis and eating disorders in adolescence. A cross-sectional study was designed including 187…

Over-the-counter sales of antibiotics from community pharmacies in Abu Dhabi.

PubMed

Dameh, Majd; Green, James; Norris, Pauline

2010-10-01

The aim of this study is to investigate over-the-counter sale of antibiotics from community pharmacies in Abu Dhabi city, focusing on the extent, demographic and socioeconomic determinants of this practice. The study was conducted in the capital of the United Arab Emirates, Abu Dhabi, and involved 17 randomly selected private pharmacies. A cross-sectional design using structured observations of 30 clients purchasing antibiotics from a pharmacy staff (either a pharmacist or pharmacy assistant) at each selected pharmacy. A total of 510 interactions were observed. Statistical analysis was performed using SPSS. The extent and types of antibiotics sold over-the-counter in Abu Dhabi city as observed in the selected sample of community pharmacies, and the demographic and socioeconomic factors that contributed to this practice. Sixty eight percent (68.4%) of the observed antibiotic sales were sold over-the-counter without prescriptions. Injection antibiotics constituted 2.2% of the antibiotics sold, 45.5% of which were sold over-the-counter. Combination of penicillins including β-lactamase inhibitors (34.0%), penicillins with extended spectrum (22.3%) and second generation cephalosporins (11.2%) were the mostly commonly sold antibiotic groups. Respiratory conditions (63.1%) were the most frequent reason for purchasing antibiotics. Over-the-counter sales of antibiotics were related to client ethnicity and age, gender of pharmacy staff and health complaint. Our study revealed high sales of over-the-counter antibiotics, despite this being illegal. The ineffectiveness of antibiotics in treating respiratory conditions of viral origin and effects of such practice on the emergence of bacterial resistance necessitates prompt action.

[Saarland Growth Study: sampling design].

PubMed

Danker-Hopfe, H; Zabransky, S

2000-01-01

The use of reference data to evaluate the physical development of children and adolescents is part of the daily routine in the paediatric ambulance. The construction of such reference data is based on the collection of extensive reference data. There are different kinds of reference data: cross sectional references, which are based on data collected from a big representative cross-sectional sample of the population, longitudinal references, which are based on follow-up surveys of usually smaller samples of individuals from birth to maturity, and mixed longitudinal references, which are a combination of longitudinal and cross-sectional reference data. The advantages and disadvantages of the different methods of data collection and the resulting reference data are discussed. The Saarland Growth Study was conducted for several reasons: growth processes are subject to secular changes, there are no specific reference data for children and adolescents from this part of the country and the growth charts in use in the paediatric praxis are possibly not appropriate any more. Therefore, the Saarland Growth Study served two purposes a) to create actual regional reference data and b) to create a database for future studies on secular trends in growth processes of children and adolescents from Saarland. The present contribution focusses on general remarks on the sampling design of (cross-sectional) growth surveys and its inferences for the design of the present study.

A randomised study of leadership interventions for healthcare managers.

PubMed

Lornudd, Caroline; Bergman, David; Sandahl, Christer; von Thiele Schwarz, Ulrica

2016-10-03

Purpose The purpose of this paper was to assess two different leader development interventions by comparing their effects on leadership behaviour and evaluating their combined impact after two years, from the viewpoints of both the participating managers and external raters. Design/methodology/approach The study was a longitudinal randomised controlled trial with a cross-over design. Health care managers ( n = 177) were first randomised to either of two 10-month interventions and a year later were switched to the other intervention. Leadership behaviour was rated at pre-test and 12 and 24 months by participating managers and their superiors, colleagues and subordinates using a 360-degree instrument. Analysis of variance and multilevel regression analysis was performed. Findings No difference in effect on leadership behaviour was found between the two interventions. The evaluation of the combined effect of the interventions on leadership behaviour showed inconsistent (i.e. both increased and decreased) ratings by the various rater sources. Practical implications This study provides some evidence that participation in leadership development programmes can improve managers' leadership behaviours, but the results also highlight the interpretive challenges connected with using a 360-degree instrument to evaluate such development. Originality/value The longitudinal randomised controlled design and the large sample comprising both managers and external raters make this study unusually rigorous in the field of leadership development evaluations.

Can a low-cost webcam be used for a remote neurological exam?

PubMed

Wood, Jeffrey; Wallin, Mitchell; Finkelstein, Joseph

2013-01-01

Multiple sclerosis (MS) is a demyelinating and axonal degenerative disease of the central nervous system. It is the most common progressive neurological disorder of young adults affecting over 1 million persons worldwide. Despite the increased use of neuroimaging and other tools to measure MS morbidity, the neurological examination remains the primary method to document relapses and progression in disease. The goal of this study was to demonstrate the feasibility and validity of using a low-cost webcam for remote neurological examination in home-setting for patients with MS. Using cross-over design, 20 MS patients were evaluated in-person and via remote televisit and results of the neurological evaluation were compared. Overall, we found that agreement between face-to-face and remote EDSS evaluation was sufficient to provide clinically valid information. Another important finding of this study was high acceptance of patients and their providers of using remote televisits for conducting neurological examinations at MS patient homes. The results of this study demonstrated potential of using low-cost webcams for remote neurological exam in patients with MS.

Prevalence and predictors of over-the-counter medication use among adolescents in the United Arab Emirates.

PubMed

Barakat-Haddad, Caroline; Siddiqua, Ayesha

2018-01-02

The patterns of over-the-counter medication (OTC) usage among adolescents living in the United Arab Emirates (UAE) remains largely understudied. The objectives of this study are: (1) to determine the profile of OTC use among UAE adolescents; and (2) to determine the biological or physical, psychological or behavioural, and social predictors of OTC use among the UAE adolescent population. Using a cross-sectional study design, data were collected on the prevalence of OTC use for a sample of 6363 adolescents. Overall, 51% of participants in this study reported OTC use. The most common form of OTC used was acetaminophen. Significant predictors of OTC use were: nationality (UAE, GCC, Arab / Middle East, Arab / Africa, Western, other); needed health care but did not receive it; sex (female); age (15-18 years); any medical diagnosis; unconventional drug use; spending more than 5 hours using TV and computer daily; and using prescription medicines. Thus, there is a need to develop public health policies and strategies that promote appropriate use of OTC in the population.

The efficacy of intra-articularly administered MYC 2095, triamcinolone hexacetonide and placebo in gonarthritis. A combined double-blind clinical trial.

PubMed

Cats, A; van IJzerloo, J A; Davinova, Y; Werthauer-Rodrigues Pereira, M; Blakemore, C B; Steiner, F J

1979-01-01

We report the results of a double-blind three-centre study, employing a cross-over design, set up to compare the efficacy of intra-articular injections of Myc 2095 (20 mg), triamcinolone hexacetonide (Lederspan) (20 mg) and placebo in 40 patients with synovitis of the knee joint. Each patient included in the study contributed data on 2 of the 3 treatment variables being compared. Seven clinical parameters were assessed every 6 weeks, while the doctor's and the patient's assessments were scored. Intra articular treatment both with Myc 2095 and triamcinolone hexacetonide proved to be effective. Placebo response was also very high. After the first Myc 2095 injection, improvement in "tenderness", "pain under load" and "swelling and hydrops" was significantly superior to that following placebo treatment. The evaluation of the second injections indicated a marked carry-over effect from the first course. This was also evident from the doctor's and patient's assessments. The importance of including a placebo in the evaluation of anti-phlogistic drugs in clinical trials, emerged from this study.

Can psychotherapists function as their own controls? Meta-analysis of the crossed therapist design in comparative psychotherapy trials.

PubMed

Falkenström, Fredrik; Markowitz, John C; Jonker, Hanske; Philips, Björn; Holmqvist, Rolf

2013-05-01

Clinical trials sometimes have the same therapists deliver more than 1 psychotherapy, ostensibly to control for therapist effects. This "crossed therapist" design makes controlling for therapist allegiance imperative, as therapists may prefer one treatment they deliver to the other(s). Research has established a strong relationship between principal investigators' allegiances and treatment outcome. Study therapists' allegiances probably also influence outcome, yet this moderating factor on outcome has never been studied. English language abstracts in PsycINFO and MEDLINE from January 1985 to December 2011 were searched for keywords psychotherapy and randomized trial. The search yielded 990 abstracts that were searched manually. Trials using the same therapists in more than 1 condition were included. Thirty-nine studies fulfilled inclusion criteria. Meta-regression analyses assessed the influence of researchers' allegiance on treatment outcome, testing the hypothesis that studies poorly controlling for therapist allegiance would show stronger influence of researcher allegiance on outcome. A single-item measure assessed researchers' reported attempts to control for therapist allegiance. Only 1 of 39 studies (3%) measured therapist treatment allegiance. Another 5 (13%) mentioned controlling for, without formally assessing, therapist allegiance. Most publications (67%) did not even mention therapist allegiance. In studies not controlling for therapist allegiance, researcher allegiance strongly influenced outcome, whereas studies reporting control for therapist allegiance showed no differential researcher allegiance. Researchers with cognitive-behavioral therapy allegiance described controlling for therapist allegiance less frequently than other researchers. The crossed therapist design is subject to bias due to differential psychotherapist allegiance. Worrisome results suggest that researchers strongly allied to a treatment may ignore therapist allegiance, potentially skewing outcomes. All clinical trials, and especially crossed therapist designs, should measure psychotherapist allegiance to evaluate this possible bias. © Copyright 2013 Physicians Postgraduate Press, Inc.

Cost-Effectiveness of Capping Freeways for Use as Parks: The New York Cross-Bronx Expressway Case Study

PubMed Central

Zafari, Zafar; Bellanger, Martine; Muennig, Peter Alexander

2018-01-01

Objectives. To examine health benefits and cost-effectiveness of implementing a freeway deck park to increase urban green space. Methods. Using the Cross-Bronx Expressway in New York City as a case study, we explored the cost-effectiveness of implementing deck parks. We built a microsimulation model that included increased exercise, fewer accidents, and less pollution as well as the cost of implementation and maintenance of the park. We estimated both the quality-adjusted life years gained and the societal costs for 2017. Results. Implementation of a deck park over sunken parts of Cross-Bronx Expressway appeared to save both lives and money. Savings were realized for 84% of Monte Carlo simulations. Conclusions. In a rapidly urbanizing world, reclaiming green space through deck parks can bring health benefits alongside economic savings over the long term. Public Health Implications. Policymakers are seeking ways to create cross-sectorial synergies that might improve both quality of urban life and health. However, such projects are very expensive, and there is little information on their return of investment. Our analysis showed that deck parks produce exceptional value when implemented over below-grade sections of road. PMID:29345999

Short-term overeating results in incomplete energy intake compensation regardless of energy density or macronutrient composition

PubMed Central

Apolzan, John W.; Bray, George A.; Hamilton, Marc T.; Zderic, Theodore W.; Han, Hongmei; Champagne, Catherine M.; Shepard, Desti; Martin, Corby K.

2013-01-01

Objective To evaluate the effects of overeating (140% of energy requirements) a high-fat low-energy density diet (HF/LED, 1.05kcal/g), high-fat high-energy density diet (HF/HED, 1.60kcal/g), and high-carbohydrate (HC) LED (1.05kcal/g) for 2-days on subsequent 4-day energy intake (EI), activity levels, appetite, and mood. Design and Methods Using a randomized cross-over design, energy expenditure and EI were standardized during overeating. Results In 20 adults with a mean±SD BMI of 30.7±4.6kg/m2, EI was not suppressed until the second day after overeating and accounted for ~30% of the excess EI. Reductions in EI did not differ among the 3 diets or across days. Overeating had no effect on subsequent energy expenditure but steps/day decreased after the HC/LED and HF/HED. Sleep time was increased after the HF/HED compared to both LEDs. After overeating a HF/HED vs. HF/LED, carbohydrate cravings, hunger, prospective food consumption, and sadness increased and satisfaction, relaxation, and tranquility decreased. Conclusions Diet type, time, or their interaction had no impact on compensation over 4 days. No adaptive thermogenesis was observed. The HF/HED vs. HF/LED had detrimental effects on food cravings, appetite, and mood. These results suggest short-term overeating is associated with incomplete compensation. PMID:23913807

Evaluating the suitability of highly cross-linked and remelted materials for use in posterior stabilized knees.

PubMed

Huot, J Caitlin; Van Citters, Douglas W; Currier, John H; Currier, Barbara H; Mayor, Michael B; Collier, John P

2010-11-01

Posterior stabilized (PS) knee designs are a popular choice for cruciate sacrificing knee arthroplasty procedures. The introduction of PS inserts fabricated from highly cross-linked and remelted Ultra High Molecular Weight Polyethylene (UHMWPE) has recently generated concern as these materials have been shown to possess reduced mechanical properties. This study investigated whether highly cross-linked and remelted UHMWPE material (referred to as XRP) can be expected to perform similarly to historical gamma-air polyethylene, which has suffered few reported incidences of tibial post failure. Never-implanted gamma-air PS tibial inserts shelf-aged 14 years were examined and compared to XRP materials. Evaluation of oxidation levels, impact toughness, and fatigue strength demonstrated never-implanted gamma-air PS tibial inserts to possess nonuniform mechanical properties. Despite severe oxidation along the exterior of gamma-air tibial posts, comparatively low oxidation levels at the center of the tibial posts corresponded to sufficiently high mechanical properties. XRP material (75 kGy) showed superior impact toughness over shelf aged gamma-air material; however, tibial post fatigue testing demonstrated XRP material (100 kGy) to be less resistant to fatigue failure than historical gamma-air material. Results from this study indicate that XRP materials (100 kGy) may demonstrate an inferior resistance to tibial post failure than historical polyethylene. © 2010 Wiley Periodicals, Inc.

Cross-calibration of the Terra MODIS, Landsat 7 ETM+ and EO-1 ALI sensors using near-simultaneous surface observation over the Railroad Valley Playa, Nevada, test site

USGS Publications Warehouse

Chander, G.; Angal, A.; Choi, T.; Meyer, D.J.; Xiong, X.; Teillet, P.M.

2007-01-01

A cross-calibration methodology has been developed using coincident image pairs from the Terra Moderate Resolution Imaging Spectroradiometer (MODIS), the Landsat 7 (L7) Enhanced Thematic Mapper Plus (ETM+) and the Earth Observing EO-1 Advanced Land Imager (ALI) to verify the absolute radiometric calibration accuracy of these sensors with respect to each other. To quantify the effects due to different spectral responses, the Relative Spectral Responses (RSR) of these sensors were studied and compared by developing a set of "figures-of-merit." Seven cloud-free scenes collected over the Railroad Valley Playa, Nevada (RVPN), test site were used to conduct the cross-calibration study. This cross-calibration approach was based on image statistics from near-simultaneous observations made by different satellite sensors. Homogeneous regions of interest (ROI) were selected in the image pairs, and the mean target statistics were converted to absolute units of at-sensor reflectance. Using these reflectances, a set of cross-calibration equations were developed giving a relative gain and bias between the sensor pair.

Walkability and cardiometabolic risk factors: Cross-sectional and longitudinal associations from the Multi-Ethnic Study of Atherosclerosis.

PubMed

Braun, Lindsay M; Rodríguez, Daniel A; Evenson, Kelly R; Hirsch, Jana A; Moore, Kari A; Diez Roux, Ana V

2016-05-01

We used data from 3227 older adults in the Multi-Ethnic Study of Atherosclerosis (2004-2012) to explore cross-sectional and longitudinal associations between walkability and cardiometabolic risk factors. In cross-sectional analyses, linear regression was used to estimate associations of Street Smart Walk Score® with glucose, triglycerides, HDL and LDL cholesterol, systolic and diastolic blood pressure, and waist circumference, while logistic regression was used to estimate associations with odds of metabolic syndrome. Econometric fixed effects models were used to estimate longitudinal associations of changes in walkability with changes in each risk factor among participants who moved residential locations between 2004 and 2012 (n=583). Most cross-sectional and longitudinal associations were small and statistically non-significant. We found limited evidence that higher walkability was cross-sectionally associated with lower blood pressure but that increases in walkability were associated with increases in triglycerides and blood pressure over time. Further research over longer time periods is needed to understand the potential for built environment interventions to improve cardiometabolic health. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microfluidic Device with Tunable Post Arrays and Integrated Electrodes for Studying Cellular Release

PubMed Central

Selimovic, Asmira; Erkal, Jayda L.; Spence, Dana M.; Martin, R. Scott

2015-01-01

In this paper, we describe the development of a planar, pillar array device that can be used to image either side of a tunable membrane, as well as sample and detect small molecules in a cell-free region of the microchip. The pores are created by sealing two parallel PDMS microchannels (a cell channel and a collector channel) over a gold pillar array (5 or 10 µm in height), with the device being characterized and optimized for small molecule cross-over while excluding a flowing cell line (here, red blood cells, RBCs). The device was characterized in terms of the flow rate dependence of cross-over of analyte and cell exclusion as well as the ability to perform amperometric detection of catechol and nitric oxide (NO) as they cross-over into the collector channel. Using catechol as the test analyte, the limits of detection (LOD) of the cross-over for the 10 µm and 5 µm pillar array heights were shown to be 50 nM and 106 nM, respectively. Detection of NO was made possible with a glassy carbon detection electrode (housed in the collector channel) modified with Pt-black and Nafion, to enhance sensitivity and selectivity, respectively. Reproducible cross-over of NO as a function of concentration resulted in a linear correlation (r2 = 0.995, 7.6 µM - 190 µM), with an LOD for NO of 230 nM on the glassy carbon-Pt-black-0.05% Nafion electrode. The applicability of the device was demonstrated by measuring the NO released from hypoxic RBCs, with the device allowing the released NO to cross-over into a cell free channel where it was detected in close to real-time. This type of device is an attractive alternative to the use of 3-dimensional devices with polycarbonate membranes, as either side of the membrane can be imaged and facile integration of electrochemical detection is possible. PMID:25105251

A longitudinal mediation analysis of the effect of negative-self-schemas on positive symptoms via negative affect.

PubMed

Jaya, E S; Ascone, L; Lincoln, T M

2018-06-01

Cognitive models postulate that negative-self-schemas (NSS) cause and maintain positive symptoms and that negative affect mediates this link. However, only few studies have tested the temporal mediation claim systematically using an appropriate design. A longitudinal cohort design in an online community sample (N = 962) from Germany, Indonesia, and the USA was used. NSS, negative affect and positive symptoms were measured at four time-points (T0-T3) over a 1-year period. Cross-lagged panel and longitudinal mediation analyses with structural equation modeling were used to test the temporal mediation. Independent cross-lagged panel models showed a significant unidirectional longitudinal path from NSS to positive symptoms (T2-T3, β = 0.18, p < 0.01) and bidirectional longitudinal associations from NSS to negative affect (T0-T1, γ = 0.14, p < 0.01) and vice versa (T0-T1, γ = 0.19, p < 0.01). There was also a significant indirect pathway from NSS at baseline via negative affect at T1 and T2 to positive symptoms at T3 (unstandardized indirect effect coefficient = 0.020, p < 0.05, BCa CI 0.004-0.035), indicating mediation. Our findings support the postulated affective pathway from NSS to positive symptoms via negative affect. Specifically, our data indicate that NSS and negative affect influence each other and build up over the course of several months before leading on to positive symptoms. We conclude that interrupting this process by targeting NSS and negative affect early in the process could be a promising strategy to prevent the exacerbation of positive symptoms.

Knowledge of Metabolic Syndrome in Chinese Adults: Implications for Health Education

ERIC Educational Resources Information Center

Lo, Sally Wai Sze; Chair, Sek Ying; Lee, Iris Fung Kam

2016-01-01

Objective: The objective of this study was to assess knowledge of metabolic syndrome (MS) among Chinese adults and provide directions for designing healthcare promotion schemes for improving MS awareness in the community. Design: The study adopted a cross-sectional design and a convenience sampling method. Method: Chinese adults aged 18-65 years…

Cross-Cultural Interface Design and the Classroom-Learning Environment in Taiwan

ERIC Educational Resources Information Center

Chang, Chia-Lin; Su, Yelin

2012-01-01

This study examined whether using localized interface designs would make a difference in users' learning results and their perceptions of the interface design in a classroom learning environment. This study also sought to learn more about users' attitudes toward the localized interface features. To assess the impact of using localized interfaces…

Personality, work characteristics, and employee well-being: a longitudinal analysis of additive and moderating effects.

PubMed

Houkes, Inge; Janssen, Peter P M; de Jonge, Jan; Bakker, Arnold B

2003-01-01

This study tested the longitudinal influence of personality (measured by the characteristics growth need strength, negative affectivity [NA], and upward striving) on 3 psychological outcomes (intrinsic work motivation, emotional exhaustion, and turnover intention), using a pattern of specific relationships between work characteristics and these outcomes as a framework. The study hypotheses were tested in a multioccupational sample consisting of bank employees and teachers, using a 2-wave panel design with a 1-year time interval and structural equation modeling. NA had a cross-lagged direct and additive relationship with emotional exhaustion and also moderated the relationship between Time 1 workload and Time 2 emotional exhaustion. The authors concluded that NA may have multiple effects on emotional exhaustion that persist over time.

Effect of an acidic beverage (Coca-Cola) on the pharmacokinetics of carbamazepine in healthy volunteers.

PubMed

Malhotra, S; Dixit, R K; Garg, S K

2002-01-01

The effect of an acidic beverage (Coca-Cola) on the pharmacokinetics of a single dose of carbamazepine was studied. In a two-way cross-over design with a 1 week washout period, 10 healthy volunteers were randomized to received 200 mg carbamazepine orally with 300 ml of Coca-Cola or water. Blood samples were collected at 0, 0.5, 1, 2, 3, 6, 9, 12, 24, 48 and 72 h after drug administration. Plasma carbamazepine levels were higher with Coca-Cola as compared to water. The AUC0-infinity and Cmax of carbamazepine were significantly enhanced after Coca-Cola while tmax was achieved earlier with Coca-Cola. The results of the study indicate that concomitant administration of Coca-Cola enhances the rate and extent of absorption of carbamazepine.

Prevalence Odds Ratio versus Prevalence Ratio: Choice Comes with Consequences

PubMed Central

Tamhane, Ashutosh R; Westfall, Andrew O; Burkholder, Greer A; Cutter, Gary R

2016-01-01

Odds ratio (OR), risk ratio (RR), and prevalence ratio (PR) are some of the measures of association which are often reported in research studies quantifying the relationship between an independent variable and the outcome of interest. There has been much debate on the issue of which measure is appropriate to report depending on the study design. However, the literature on selecting a particular category of the outcome to be modeled and/or change in reference group for categorical independent variables and the effect on statistical significance, although known, is scantly discussed nor published with examples. In this article, we provide an example of a cross-sectional study wherein PR was chosen over (Prevalence) OR and demonstrate the analytic implications of the choice of category to be modeled and choice of reference level for independent variables. PMID:27460748

Impact of HMO mergers and acquisitions on financial performance.

PubMed

Weech-Maldonado, Robert

2002-01-01

This study examines the effect of health maintenance organization (HMO) mergers and acquisitions on financial performance, as indicated by cash flow returns, profitability ratios, and efficiency indicators. Pooled, cross-sectional files of financial performance data were created for HMO mergers occurring in the period of 1988 to 1994. The study uses a time-series design involving the analysis of pre- and post-acquisition financial performance measured over a period of four years. Change scores for the industry-adjusted financial performance measures were calculated and then evaluated using t-tests. The study showed that HMO mergers had a positive effect on financial performance and efficiency. This effect disappeared, however, after adjusting for HMO industry returns. Potential synergies arising from HMO mergers have been largely illusory. Mergers may have been a result of non-value enhancing motives or management overconfidence.

Reciprocal relations between teacher-child conflict and aggressive behavior in kindergarten: a three-wave longitudinal study.

PubMed

Doumen, Sarah; Verschueren, Karine; Buyse, Evelien; Germeijs, Veerle; Luyckx, Koen; Soenens, Bart

2008-07-01

In recent developmental theorizing, it has been hypothesized that teacher-child conflict and children's externalizing behavior affect one another reciprocally over time. However, the relation between teacher-child conflict and externalizing behavior has been mainly studied from a unidirectional point of view. Therefore, this study aimed to test the hypothesis of bidirectionality by means of a cross-lagged longitudinal design with kindergarten teacher reports on core variables at 3 measurement occasions in 1 year. Structural equation modeling with data of 148 kindergartners provided evidence for the hypothesis of bidirectionality. Specifically, results supported a transactional sequence in which children's aggressive behavior at the beginning of kindergarten led to increases in teacher-child conflict midyear, which in turn led to an increase of aggressive behavior at the end of the kindergarten school year.

Using Popular Movies in Teaching Cross-Cultural Management

ERIC Educational Resources Information Center

Pandey, Satish

2012-01-01

Purpose: The present study aims to understand context and dynamics of cognitive learning of students as an outcome of the usage of popular movies as a learning tool in the management classroom and specifically in the context of a course on cross-cultural management issues. Design/methodology/approach: This is an exploratory study based on…

A Cross-Cultural Study of Self-Report Depressive Symptoms among College Students.

ERIC Educational Resources Information Center

Crittenden, Kathleen S.; And Others

1992-01-01

A study of self-report depressive symptoms measured by the Zung Self-Rating Depression Scale was conducted in Korea, the Philippines, Taiwan, and the United States with 953 college students. There are marked differences among countries in symptoms reported. Research designs and measurement strategies for cross-cultural research are discussed. (SLD)

End-of-High-School Mathematics Attainment: How Did Students Get There?

ERIC Educational Resources Information Center

Newton, Xiaoxia A.

2010-01-01

Background: Many studies have looked at students' mathematics achievement in the middle and high school years and the kinds of factors that are associated with their achievement. Within this domain, however, most research utilized cross-sectional data. Cross-sectional designs have both statistical and conceptual limitations. Few studies used…

Evaluating the effect of energy-dense foods consumption on preschool children's body mass index: a prospective analysis from 2 to 4 years of age.

PubMed

Durão, Catarina; Severo, Milton; Oliveira, Andreia; Moreira, Pedro; Guerra, António; Barros, Henrique; Lopes, Carla

2015-08-01

The aim of this study was to study the association between the consumption of energy-dense foods at 2 years and body mass index (BMI) at 4 years, using a cross-lagged panel design. The present study included 589 children evaluated at 2 and 4 years of age, as part of the birth cohort generation XXI. Information was obtained by face-to-face interviews. Consumption of energy-dense foods (salty snacks, soft drinks, cakes, and sweets) was measured using a food frequency questionnaire. Children's weight and height were measured by standard procedures, and BMI standard deviation scores (BMI z-scores) were calculated according to the World Health Organization. Linear regression and cross-lagged panel design models were fitted to estimate the associations between the consumption of energy-dense foods and BMI z-scores (controlled for maternal age, education and prepregnancy BMI, and children's exact age at 2 years). The consumption of energy-dense foods at 2 years was significantly associated with their consumption at 4 years (β = 0.522, 95% CI 0.432-0.612). Children's BMI z-scores at 2 years were associated with posterior BMI z-scores (β = 0.747, 95% CI 0.688-0.806). In the cross-lagged analysis, consumption of energy-dense foods at 2 years had no effect on subsequent BMI z-scores (β = -0.030, 95% CI -0.095 to 0.035) and BMI z-scores at 2 years were not significantly associated with the consumption of energy-dense foods at 4 years (β = -0.012, 95% CI -0.086 to 0.062). Consumption of energy-dense foods and BMI tracked over time, but the consumption of energy-dense foods at 2 years was not associated with BMI z-scores at 4 years.

A systematic review of global publication trends regarding long-term outcomes of ADHD.

PubMed

Hodgkins, Paul; Arnold, L Eugene; Shaw, Monica; Caci, Hervé; Kahle, Jennifer; Woods, Alisa G; Young, Susan

2011-01-01

There is increased global recognition of attention deficit hyperactivity disorder (ADHD) as a serious medical condition with long-term consequences. Although originally conceived of as a childhood disorder, ADHD is being increasingly recognized in adults. Individual geographic regions may have specific interests and objectives for the study of ADHD. A systematic review of long-term outcomes (LTOs) in ADHD was conducted to evaluate research on ADHD LTOs on a global scale. Studies that were at least 2 years in duration were examined. A total of 351 studies were identified in the final analysis. We identified nine outcomes of interest and classified studies by specific geographical regions, age groups studied and study design by region and over time. Published studies of LTOs in ADHD have increased in all geographical regions over the past three decades, with a peak number of 42 publications in 2008. This rise in publications on ADHD LTOs may reflect a rise in global interest and recognition of consequences and impairment associated with ADHD. Although many world regions have published on ADHD LTOs, the majority of studies have emerged from the US and Canada, followed by Europe. While investigators in the US and Canada were predominantly interested in drug addiction as a LTO, European researchers were more interested in antisocial behavior, and Eastern Asian investigators focused on both of these LTOs as well as self-esteem. Geographical differences in the focus of ADHD LTO studies may reflect regional variations in cultural values. Proportionally fewer prospective longitudinal studies and proportionally more retrospective and cross-sectional studies have been published in more recent decades. Finally, more studies focusing on ADHD in adolescents and adults have been conducted in recent years, and particularly adolescents in Eastern Asia. These changes in basic study design may reflect an increase in the recognition that ADHD is a lifetime chronic disorder. This systematic review analysis of publication trends in ADHD LTOs reflects geographically based interests that change over time.

A Systematic Review of Global Publication Trends Regarding Long-Term Outcomes of ADHD

PubMed Central

Hodgkins, Paul; Arnold, L. Eugene; Shaw, Monica; Caci, Hervé; Kahle, Jennifer; Woods, Alisa G; Young, Susan

2012-01-01

There is increased global recognition of attention deficit hyperactivity disorder (ADHD) as a serious medical condition with long-term consequences. Although originally conceived of as a childhood disorder, ADHD is being increasingly recognized in adults. Individual geographic regions may have specific interests and objectives for the study of ADHD. A systematic review of long-term outcomes (LTOs) in ADHD was conducted to evaluate research on ADHD LTOs on a global scale. Studies that were at least 2 years in duration were examined. A total of 351 studies were identified in the final analysis. We identified nine outcomes of interest and classified studies by specific geographical regions, age groups studied and study design by region and over time. Published studies of LTOs in ADHD have increased in all geographical regions over the past three decades, with a peak number of 42 publications in 2008. This rise in publications on ADHD LTOs may reflect a rise in global interest and recognition of consequences and impairment associated with ADHD. Although many world regions have published on ADHD LTOs, the majority of studies have emerged from the US and Canada, followed by Europe. While investigators in the US and Canada were predominantly interested in drug addiction as a LTO, European researchers were more interested in antisocial behavior, and Eastern Asian investigators focused on both of these LTOs as well as self-esteem. Geographical differences in the focus of ADHD LTO studies may reflect regional variations in cultural values. Proportionally fewer prospective longitudinal studies and proportionally more retrospective and cross-sectional studies have been published in more recent decades. Finally, more studies focusing on ADHD in adolescents and adults have been conducted in recent years, and particularly adolescents in Eastern Asia. These changes in basic study design may reflect an increase in the recognition that ADHD is a lifetime chronic disorder. This systematic review analysis of publication trends in ADHD LTOs reflects geographically based interests that change over time. PMID:22279437

The PCIe-based readout system for the LHCb experiment

NASA Astrophysics Data System (ADS)

Cachemiche, J. P.; Duval, P. Y.; Hachon, F.; Le Gac, R.; Réthoré, F.

2016-02-01

The LHCb experiment is designed to study differences between particles and anti-particles as well as very rare decays in the beauty and charm sector at the LHC. The detector will be upgraded in 2019 in order to significantly increase its efficiency, by removing the first-level hardware trigger. The upgrade experiment will implement a trigger-less readout system in which all the data from every LHC bunch-crossing are transported to the computing farm over 12000 optical links without hardware filtering. The event building and event selection are carried out entirely in the farm. Another original feature of the system is that data transmitted through these fibres arrive directly to computers through a specially designed PCIe card called PCIe40. The same board handles the data acquisition flow and the distribution of fast and slow controls to the detector front-end electronics. It embeds one of the most powerful FPGAs currently available on the market with 1.2 million logic cells. The board has a bandwidth of 480 Gbits/s in both input and output over optical links and 100 Gbits/s over the PCI Express bus to the CPU. We will present how data circulate through the board and in the PC server for achieving the event building. We will focus on specific issues regarding the design of such a board with a very large FPGA, in particular in terms of power supply dimensioning and thermal simulations. The features of the board will be detailed and we will finally present the first performance measurements.

Preliminary Structural Design Considerations and Mass Efficiencies for Lunar Surface Manipulator Concepts

NASA Technical Reports Server (NTRS)

Dorsey, John T.; Mikulas, Martin M.; Doggett, William R.

2008-01-01

The mass and sizing characteristics of manipulators for Lunar and Mars planetary surface applications are investigated by analyzing three structural configurations: a simple cantilevered boom with a square tubular cross-section; a hybrid cable/boom configuration with a square tubular cross-section support structure; and a hybrid cable/boom configuration with a square truss cross-section support structure. Design procedures are developed for the three configurations and numerical examples are given. A new set of performance parameters are developed that relate the mass of manipulators and cranes to a loading parameter. These parameters enable the masses of different manipulator configurations to be compared over a wide range of design loads and reach envelopes (radii). The use of these parameters is demonstrated in the form of a structural efficiency chart using the newly considered manipulator configurations. To understand the performance of Lunar and Mars manipulators, the design procedures were exercised on the three manipulator configurations assuming graphite/epoxy materials for the tubes and trusses. It is also assumed that the actuators are electric motor, gear reduction systems. Numerical results for manipulator masses and sizes are presented for a variety of manipulator reach and payload mass capabilities. Results are presented that demonstrate the sensitivity of manipulator mass to operational radius, tip force, and actuator efficiency. The effect of the value of gravitational force on the ratio of manipulator-mass to payload-mass is also shown. Finally, results are presented to demonstrate the relative mass reduction for the use of graphite/epoxy compared to aluminum for the support structure.

The Categorical Stability of Gambling Motives Among Community-Recruited Gamblers: A Longitudinal Assessment.

PubMed

McGrath, Daniel S; Konkolÿ Thege, Barna

2018-03-01

Over the past decade, several motivational models have been proposed to explain the role of motives in gambling disorder. In the model captured by the four-factor Gambling Motives Questionnaire Financial (GMQ-F), gamblers are described as being primarily motivated to gamble for 'coping', 'enhancement', 'social', and 'financial' reasons. Although this model has received significant empirical support; to date, research assessing the role of motives in gambling disorder has been primarily cross-sectional in nature. Thus, the extent to which gambling motives remain stable over time has yet to be explored. In the current study, the stability versus fluidity of self-assessed gambling motives was investigated using the Quinte Longitudinal Study, a longitudinal dataset of gambling behaviour collected over 5 years. Gambling motives of 2795 gamblers were examined over all five annual assessments. The total proportion of gamblers who stayed in the same primary motive category across each of the 5 consecutive assessments was 22%, indicating substantial fluidity in category membership. Substantial movement between categories was seen for each GMQ-F group, as well as an additional group of non-classified motives. Logistic regression analyses suggest that greater resistance to gambling fallacies significantly predicted stability between the baseline assessment and a follow-up 1 year later, but gambling severity did not. Potential limitations in the study design and opportunities for future research are discussed.

Where are my hands? Influence of limb posture on tactile extinction.

PubMed

Auclair, Laurent; Barra, Julien; Raibaut, Patrick

2012-05-01

Tactile localization on the skin involves both a somatotopic and a postural schema (body-schema) representation. The present study determines the extent to which body posture influences tactile perception in right-brain-damaged patients. In a first set of experiments, patients were asked to detect single tactile stimulation delivered to their left or right hands or to both hands simultaneously (double stimulation) in different arm postures. Only patients who had no difficulty localizing single and double tactile stimulations when their hands were placed in anatomic position were tested. Participant's hands were crossed, one over the other, and the tactile stimuli were delivered either to the hand (beyond the crossing point, Experiment 1) or to the forearm (before the crossing point, Experiment 2). In Experiment 3, the left hand was placed in the right hemispace and the right hand in the left hemispace without crossing over (opposite condition). In a second set of experiments, patients were asked to detect stimulation delivered to the forefinger. The fingers were crossed, one over the other at the level of the middle phalanx, and stimuli were delivered either beyond or before the crossing point. In all experimental conditions, control participants performed at ceiling. We observed a left-hand tactile extinction on double stimulation in the crossed condition. These results suggest that tactile stimuli can be encoded based on multiple specific body-part representations rather than on an integrated body-schema representation.

Stepping over obstacles: gait patterns of healthy young and old adults.

PubMed

Chen, H C; Ashton-Miller, J A; Alexander, N B; Schultz, A B

1991-11-01

Falls associated with tripping over an obstacle can be devastating to elderly individuals, yet little is known about the strategies used for stepping over obstacles by either old or young adults. The gait of gender-matched groups of 24 young and 24 old healthy adults (mean ages 22 and 71 years) was studied during a 4 m approach to and while stepping over obstacles of 0, 25, 51, or 152 mm height and in level obstacle-free walking. Optoelectronic cameras and recorders were used to record approach and obstacle crossing speeds as well as bilateral lower extremity kinematic parameters that described foot placement and movement trajectories relative to the obstacle. The results showed that age had no effect on minimum swing foot clearance (FC) over an obstacle. For the 25 mm obstacle, mean FC was 64 mm, or approximately three times that used in level gait; FC increased nonlinearly with obstacle height for all subjects. Although no age differences were found in obstacle-free gait, old adults exhibited a significantly more conservative strategy when crossing obstacles, with slower crossing speed, shorter step length, and shorter obstacle-heel strike distance. In addition, the old adults crossed the obstacle so that it was 10% further forward in their obstacle-crossing step. Although all subjects successfully avoided the riskiest form of obstacle contact, tripping, 4/24 healthy old adults stepped on an obstacle, demonstrating an increased risk for obstacle contact with age.

Whole-body cryotherapy (extreme cold air exposure) for preventing and treating muscle soreness after exercise in adults.

PubMed

Costello, Joseph T; Baker, Philip R A; Minett, Geoffrey M; Bieuzen, Francois; Stewart, Ian B; Bleakley, Chris

2015-09-18

Recovery strategies are often used with the intention of preventing or minimising muscle soreness after exercise. Whole-body cryotherapy, which involves a single or repeated exposure(s) to extremely cold dry air (below -100 °C) in a specialised chamber or cabin for two to four minutes per exposure, is currently being advocated as an effective intervention to reduce muscle soreness after exercise. To assess the effects (benefits and harms) of whole-body cryotherapy (extreme cold air exposure) for preventing and treating muscle soreness after exercise in adults. We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, the British Nursing Index and the Physiotherapy Evidence Database. We also searched the reference lists of articles, trial registers and conference proceedings, handsearched journals and contacted experts.The searches were run in August 2015. We aimed to include randomised and quasi-randomised trials that compared the use of whole-body cryotherapy (WBC) versus a passive or control intervention (rest, no treatment or placebo treatment) or active interventions including cold or contrast water immersion, active recovery and infrared therapy for preventing or treating muscle soreness after exercise in adults. We also aimed to include randomised trials that compared different durations or dosages of WBC. Our prespecified primary outcomes were muscle soreness, subjective recovery (e.g. tiredness, well-being) and adverse effects. Two review authors independently screened search results, selected studies, assessed risk of bias and extracted and cross-checked data. Where appropriate, we pooled results of comparable trials. The random-effects model was used for pooling where there was substantial heterogeneity. We assessed the quality of the evidence using GRADE. Four laboratory-based randomised controlled trials were included. These reported results for 64 physically active predominantly young adults (mean age 23 years). All but four participants were male. Two trials were parallel group trials (44 participants) and two were cross-over trials (20 participants). The trials were heterogeneous, including the type, temperature, duration and frequency of WBC, and the type of preceding exercise. None of the trials reported active surveillance of predefined adverse events. All four trials had design features that carried a high risk of bias, potentially limiting the reliability of their findings. The evidence for all outcomes was classified as 'very low' quality based on the GRADE criteria.Two comparisons were tested: WBC versus control (rest or no WBC), tested in four studies; and WBC versus far-infrared therapy, also tested in one study. No studies compared WBC with other active interventions, such as cold water immersion, or different types and applications of WBC.All four trials compared WBC with rest or no WBC. There was very low quality evidence for lower self-reported muscle soreness (pain at rest) scores after WBC at 1 hour (standardised mean difference (SMD) -0.77, 95% confidence interval (CI) -1.42 to -0.12; 20 participants, 2 cross-over trials); 24 hours (SMD -0.57, 95% CI -1.48 to 0.33) and 48 hours (SMD -0.58, 95% CI -1.37 to 0.21), both with 38 participants, 2 cross-over studies, 1 parallel group study; and 72 hours (SMD -0.65, 95% CI -2.54 to 1.24; 29 participants, 1 cross-over study, 1 parallel group study). Of note is that the 95% CIs also included either no between-group differences or a benefit in favour of the control group. One small cross-over trial (9 participants) found no difference in tiredness but better well-being after WBC at 24 hours post exercise. There was no report of adverse events.One small cross-over trial involving nine well-trained runners provided very low quality evidence of lower levels of muscle soreness after WBC, when compared with infrared therapy, at 1 hour follow-up, but not at 24 or 48 hours. The same trial found no difference in well-being but less tiredness after WBC at 24 hours post exercise. There was no report of adverse events. There is insufficient evidence to determine whether whole-body cryotherapy (WBC) reduces self-reported muscle soreness, or improves subjective recovery, after exercise compared with passive rest or no WBC in physically active young adult males. There is no evidence on the use of this intervention in females or elite athletes. The lack of evidence on adverse events is important given that the exposure to extreme temperature presents a potential hazard. Further high-quality, well-reported research in this area is required and must provide detailed reporting of adverse events.

A cross-lagged model of the reciprocal associations of loneliness and memory functioning.

PubMed

Ayalon, Liat; Shiovitz-Ezra, Sharon; Roziner, Ilan

2016-05-01

The study was designed to evaluate the reciprocal associations of loneliness and memory functioning using a cross-lagged model. The study was based on the psychosocial questionnaire of the Health and Retirement Study, which is a U.S. nationally representative survey of individuals over the age of 50 and their spouses of any age. A total of 1,225 respondents had complete data on the loneliness measure in 2004 and at least in 1 of the subsequent waves (e.g., 2008, 2012) and were maintained for analysis. A cross-lagged model was estimated to examine the reciprocal associations of loneliness and memory functioning, controlling for age, gender, education, depressive symptoms, number of medical conditions, and the number of close social relationships. The model had adequate fit indices: χ2(860, N = 1,225) = 1,401.54, p < .001, Tucker-Lewis index = .957, comparative fit index = .963, and root mean square error of approximation = .023 (90% confidence interval [.021, .025]). The lagged effect of loneliness on memory functioning was nonsignificant, B(SE) = -.11(.08), p = .15, whereas the lagged effect of memory functioning on loneliness was significant, B(SE) = -.06(.02), p = .01, indicating that lower levels of memory functioning precede higher levels of loneliness 4 years afterward. Further research is required to better understand the mechanisms responsible for the temporal association between reduced memory functioning and increased loneliness. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Influence of two different flap designs on the sequelae of mandibular third molar surgery.

PubMed

Erdogan, Ozgür; Tatlı, Ufuk; Ustün, Yakup; Damlar, Ibrahim

2011-09-01

The aim of this study was to compare the influence of triangular and envelope flaps on trismus, pain, and facial swelling after mandibular third molar surgery. Twenty healthy patients with bilateral, symmetrically impacted mandibular third molars were included in this double-blinded, prospective, cross-over, randomized study. The patients were operated with envelope flap on one side and triangular flap on the other side. Trismus was determined by measuring maximum interincisal opening, and facial swelling was evaluated using a tape measuring method. Pain was determined using visual analog scale (VAS) and recording the number of pain pills taken. The facial swelling measurements and VAS scores were lower in the envelope flap group compared to the triangular flap group. There was no significant difference between the two flap designs in operation time, maximum interincisal opening, and the number of analgesics taken. Envelope flap yields to less facial swelling and reduced VAS scores in comparison to triangular flap. There is no clinical difference in trismus between the two flap designs. Despite the higher VAS scores with triangular flap, no additional doses of analgesics were required in triangular flap.

Comparison of safety effect estimates obtained from empirical Bayes before-after study, propensity scores-potential outcomes framework, and regression model with cross-sectional data.

PubMed

Wood, Jonathan S; Donnell, Eric T; Porter, Richard J

2015-02-01

A variety of different study designs and analysis methods have been used to evaluate the performance of traffic safety countermeasures. The most common study designs and methods include observational before-after studies using the empirical Bayes method and cross-sectional studies using regression models. The propensity scores-potential outcomes framework has recently been proposed as an alternative traffic safety countermeasure evaluation method to address the challenges associated with selection biases that can be part of cross-sectional studies. Crash modification factors derived from the application of all three methods have not yet been compared. This paper compares the results of retrospective, observational evaluations of a traffic safety countermeasure using both before-after and cross-sectional study designs. The paper describes the strengths and limitations of each method, focusing primarily on how each addresses site selection bias, which is a common issue in observational safety studies. The Safety Edge paving technique, which seeks to mitigate crashes related to roadway departure events, is the countermeasure used in the present study to compare the alternative evaluation methods. The results indicated that all three methods yielded results that were consistent with each other and with previous research. The empirical Bayes results had the smallest standard errors. It is concluded that the propensity scores with potential outcomes framework is a viable alternative analysis method to the empirical Bayes before-after study. It should be considered whenever a before-after study is not possible or practical. Copyright © 2014 Elsevier Ltd. All rights reserved.

Rational Design, Synthesis and Evaluation of γ-CD-Containing Cross-Linked Polyvinyl Alcohol Hydrogel as a Prednisone Delivery Platform.

PubMed

Marican, Adolfo; Avila-Salas, Fabián; Valdés, Oscar; Wehinger, Sergio; Villaseñor, Jorge; Fuentealba, Natalia; Arenas-Salinas, Mauricio; Argandoña, Yerko; Carrasco-Sánchez, Verónica; Durán-Lara, Esteban F

2018-03-07

This study describes the in-silico rational design, synthesis and evaluation of cross-linked polyvinyl alcohol hydrogels containing γ-cyclodextrin (γ-CDHSAs) as platforms for the sustained release of prednisone (PDN). Through in-silico studies using semi-empirical quantum mechanical calculations, the effectiveness of 20 dicarboxylic acids to generate a specific cross-linked hydrogel capable of supporting different amounts of γ-cyclodextrin (γ-CD) was evaluated. According to the interaction energies calculated with the in-silico studies, the hydrogel made from PVA cross-linked with succinic acids (SA) was shown to be the best candidate for containing γ-CD. Later, molecular dynamics simulation studies were performed in order to evaluate the intermolecular interactions between PDN and three cross-linked hydrogel formulations with different proportions of γ-CD (2.44%, 4.76% and 9.1%). These three cross-linked hydrogels were synthesized and characterized. The loading and the subsequent release of PDN from the hydrogels were investigated. The in-silico and experimental results showed that the interaction between PDN and γ-CDHSA was mainly produced with the γ-CDs linked to the hydrogels. Thus, the unique structures and properties of γ-CDHSA demonstrated an interesting multiphasic profile that could be utilized as a promising drug carrier for controlled, sustained and localized release of PDN.

Rational Design, Synthesis and Evaluation of γ-CD-Containing Cross-Linked Polyvinyl Alcohol Hydrogel as a Prednisone Delivery Platform

PubMed Central

Marican, Adolfo; Valdés, Oscar; Wehinger, Sergio; Villaseñor, Jorge; Fuentealba, Natalia; Argandoña, Yerko; Carrasco-Sánchez, Verónica

2018-01-01

This study describes the in-silico rational design, synthesis and evaluation of cross-linked polyvinyl alcohol hydrogels containing γ-cyclodextrin (γ-CDHSAs) as platforms for the sustained release of prednisone (PDN). Through in-silico studies using semi-empirical quantum mechanical calculations, the effectiveness of 20 dicarboxylic acids to generate a specific cross-linked hydrogel capable of supporting different amounts of γ-cyclodextrin (γ-CD) was evaluated. According to the interaction energies calculated with the in-silico studies, the hydrogel made from PVA cross-linked with succinic acids (SA) was shown to be the best candidate for containing γ-CD. Later, molecular dynamics simulation studies were performed in order to evaluate the intermolecular interactions between PDN and three cross-linked hydrogel formulations with different proportions of γ-CD (2.44%, 4.76% and 9.1%). These three cross-linked hydrogels were synthesized and characterized. The loading and the subsequent release of PDN from the hydrogels were investigated. The in-silico and experimental results showed that the interaction between PDN and γ-CDHSA was mainly produced with the γ-CDs linked to the hydrogels. Thus, the unique structures and properties of γ-CDHSA demonstrated an interesting multiphasic profile that could be utilized as a promising drug carrier for controlled, sustained and localized release of PDN. PMID:29518980

A Holistic Approach for Risk Management During Design

NASA Technical Reports Server (NTRS)

Meshkat, Leila

2006-01-01

In this paper, an approach for the identification, assessment, mitigation and continuous management of risks during the process of designing a space mission is presented. This approach has been developed by observing the risk patterns that occur at the Project Design Center of the Jet Propulsion Laboratory (TeamX) which develops conceptual, concurrent design of Space Missions. TeamX develops an end-to-end conceptual design of a Space Mission in a matter of one or two weeks. As the risk chair in TeamX, the author has had the opportunity to observe the risk patterns that occur during design over the course of many design sessions. This paper introduces an abstraction and generalization of those patterns. Risk is defined as anything that can go wrong, along with its approximate likelihood and consequence. The indicators, and causes, and effects of these risks are cross cutting across the multiple levels of people and processes involved in the design, and the actual design product itself.

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.

Pharmacodynamic evaluation of intragastric pH and implications for famotidine dosing in the prophylaxis of non-steroidal anti-inflammatory drug induced gastropathy-a proof of concept analysis.

PubMed

Kent, Jeffery D; Holt, Robert J; Jung, Donald; Tidmarsh, George F; Grahn, Amy Y; Ball, Julie; Peura, David A

2014-01-01

Famotidine given at a dose of 80 mg/day is effective in preventing NSAID-induced gastropathy. The aim of this proof of concept study was to compare twice a day (BID) vs 3-times a day (TID) administration of this total dose of famotidine on intragastric pH in healthy volunteers. Two analyses were undertaken: (1) a 13 subject controlled cross-over 24-h intragastric pH evaluation of the BID and TID administration of 80 mg/day of famotidine, as well as measures for drug accumulation over 5 days (EudraCT, number 2006-002930-39); and (2) a pharmacokinetic (PK)/pharmacodynamic (PD) model which predicted steady-state famotidine plasma concentrations and pH of the two regimens. For the cross-over study, gastric pH was above 3.5 for a mean of 20 min longer for TID dosing compared to BID dosing on Day 1. On Day 5, the mean time above this threshold was higher with the BID regimen by ∼25 min. For pH 4, subjects' gastric pH was above this pH value for a mean of 25 min longer for TID dosing compared to BID dosing on Day 1. For Day 5, the pH was above 4 for ∼45 min longer with the TID regimen as compared with the BID regimen. The mean 24-h gastric pH values when taken in the upright position trended higher for the TID dosing period compared to the BID regimen on Day 1. The steady-state simulation model indicated that, following TID dosing, intragastric pH will be above 3 for 24 h vs 16 h for the BID regimen. There was no evidence for plasma accumulation of famotidine with TID dosing as compared to BID dosing from either analysis. The data indicate that overall more time is spent above the acidic threshold pH values when 80 mg/day of famotidine is administered TID vs BID. Key limitations included small study size with a short duration and lack of a baseline examination, but was compensated for by the cross-over and PK/PD modeling design. Although most of the comparisons in this proof of concept study were not statistically significant these results have important implications for future research on gastric acid lowering agents used for the prevention of NSAID-induced gastropathy.

Photouncaged Sequence-specific Interstrand DNA Cross-Linking with Photolabile 4-oxo-enal-modified Oligonucleotides

PubMed Central

Sun, Jingjing; Tang, Xinjing

2015-01-01

DNA cross-linking technology is an attractive tool for the detection, regulation, and manipulation of genes. In this study, a series of photolabile 4-oxo-enal-modified oligonucleotides functionalized with photosensitive ο-nitrobenzyl derivatives were rationally designed as a new kind of photocaged cross-linking agents. A comprehensive evaluation of cross-linking reactions for different nucleobases in complementary strands under different conditions suggested that the modified DNA oligonucleotides tended to form interstrand cross-linking to nucleobases with the potential of thymidine > guanosine » cytidine ~ adenosine. Different from previous literature reports that cytidine and adenosine were preferential cross-linked nucleobases with 4-oxo-enal moieties, our study represents the first example of DNA cross-linking for T and G selectivity using 4-oxo-enal moiety. The cross-linked adducts were identified and their cross-linking mechanism was also illustrated. This greatly expands the applications of 4-oxo-enal derivatives in the studies of DNA damage and RNA structure PMID:26020694

Photouncaged Sequence-specific Interstrand DNA Cross-Linking with Photolabile 4-oxo-enal-modified Oligonucleotides.

PubMed

Sun, Jingjing; Tang, Xinjing

2015-05-28

DNA cross-linking technology is an attractive tool for the detection, regulation, and manipulation of genes. In this study, a series of photolabile 4-oxo-enal-modified oligonucleotides functionalized with photosensitive ο-nitrobenzyl derivatives were rationally designed as a new kind of photocaged cross-linking agents. A comprehensive evaluation of cross-linking reactions for different nucleobases in complementary strands under different conditions suggested that the modified DNA oligonucleotides tended to form interstrand cross-linking to nucleobases with the potential of thymidine > guanosine » cytidine ~ adenosine. Different from previous literature reports that cytidine and adenosine were preferential cross-linked nucleobases with 4-oxo-enal moieties, our study represents the first example of DNA cross-linking for T and G selectivity using 4-oxo-enal moiety. The cross-linked adducts were identified and their cross-linking mechanism was also illustrated. This greatly expands the applications of 4-oxo-enal derivatives in the studies of DNA damage and RNA structure.