Study on novel functional materials carboxymethyl cellulose lithium (CMC-Li) improve high-performance lithium-ion battery.

PubMed

Qiu, Lei; Shao, Ziqiang; Xiang, Pan; Wang, Daxiong; Zhou, Zhenwen; Wang, Feijun; Wang, Wenjun; Wang, Jianquan

2014-09-22

Novel cellulose derivative CMC-Li was synthesized by cotton as raw material. The mechanism of the CMC-Li modified electrode materials by electrospinning was reported. CMC-Li/lithium iron phosphate (LiFePO4, LFP) composite fiber coated with LFP and CMC-Li nanofibers was successfully obtained by electrospinning. Then, CMC-Li/LFP nano-composite fiber was carbonized under nitrogen at a high temperature formed CNF/LFP/Li (CLL) composite nanofibers as cathode material. It can increase the contents of Li+, and improving the diffusion efficiency and specific capacity. The battery with CLL as cathode material retained close to 100% of initial reversible capacity after 200 cycles at 168 mAh g(-1), which was nearly the theoretical specific capacity of LFP. The cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and scanning electron microscope (SEM) were characterizing material performance. The batteries have good electrochemical property, outstanding pollution-free, excellent stability. Copyright © 2014 Elsevier Ltd. All rights reserved.

Synchronous versus Asynchronous CMC and Transfer to Japanese Oral Performance

ERIC Educational Resources Information Center

Hirotani, Maki

2009-01-01

This study investigated the effects of synchronous and asynchronous CMC (computer-mediated communication)on the development of linguistic features of learners' speech in Japanese. Using learners from fourth-semester Japanese classes, the following research questions were examined: (a) Does CMC have positive effects on the development of oral…

Generic Pharmaceutical Association (GPhA) - 2015 CMC Workshop (June 9-10, 2015 - Bethesda, Maryland, USA).

PubMed

Komlos, D

2015-07-01

Nearly 400 professionals attended the 2-day Generic Pharmaceutical Association (GPhA) workshop dedicated to fostering discussions on the FDA's chemistry, manufacturing and controls (CMC) expectations for abbreviated new drug applications (ANDAs), enhanced regulatory filing requirements, and other topics, as CMC takes root in the Office of Pharmaceutical Quality (OPQ). Following the keynote address by Janet Woodcock, Director of the FDA's Center for Drug Evaluation and Research (CDER) and Acting Director of OPQ, and an update from the Office of Generic Drugs (OGD) by Ted Sherwood, Acting Director of the OGD's Office of Regulatory Operations, plenary sessions took place covering OPQ updates, management plans, Generic Drug User Fee Amendments of 2012 (GDUFA) backlog, year 1 and 2 cohorts, drug substance, defining starting materials, quality related refuse-to-receive standards, risk and team-based integrated quality assessment, deficiencies and information requests - CMC submissions, emerging technologies, compliance and inspection, lifecycle management of drug products, quality metrics, pharmaceutically relevant dissolution specifications, and communication and project management. This report will provide a summary of conference highlights. Copyright 2015 Prous Science, S.A.U. or its licensors. All rights reserved.

Gender and CMC: A Review on Conflict and Harassment

ERIC Educational Resources Information Center

Li, Qing

2005-01-01

This paper reviews the literature related to gender and communication in CMC environments. A brief summary of gender related literature concerning general communication patterns in CMC is outlined first, to set the stage. Then, a review of literature in gender and CMC with a specific focus on conflict and harassment is presented. Comments upon…

Q-marker based strategy for CMC research of Chinese medicine: A case study of Panax Notoginseng saponins.

PubMed

Zhong, Yi; Zhu, Jieqiang; Yang, Zhenzhong; Shao, Qing; Fan, Xiaohui; Cheng, Yiyu

2018-01-31

To ensure pharmaceutical quality, chemistry, manufacturing and control (CMC) research is essential. However, due to the inherent complexity of Chinese medicine (CM), CMC study of CM remains a great challenge for academia, industry, and regulatory agencies. Recently, quality-marker (Q-marker) was proposed to establish quality standards or quality analysis approaches of Chinese medicine, which sheds a light on Chinese medicine's CMC study. Here manufacture processes of Panax Notoginseng Saponins (PNS) is taken as a case study and the present work is to establish a Q-marker based research strategy for CMC of Chinese medicine. The Q-markers of Panax Notoginseng Saponins (PNS) is selected and established by integrating chemical profile with pharmacological activities. Then, the key processes of PNS manufacturing are identified by material flow analysis. Furthermore, modeling algorithms are employed to explore the relationship between Q-markers and critical process parameters (CPPs) of the key processes. At last, CPPs of the key processes are optimized in order to improving the process efficiency. Among the 97 identified compounds, Notoginsenoside R 1 , ginsenoside Rg 1 , Re, Rb 1 and Rd are selected as the Q-markers of PNS. Our analysis on PNS manufacturing show the extraction process and column chromatography process are the key processes. With the CPPs of each process as the inputs and Q-markers' contents as the outputs, two process prediction models are built separately for the extraction process and column chromatography process of Panax notoginseng, which both possess good prediction ability. Based on the efficiency models of extraction process and column chromatography process we constructed, the optimal CPPs of both processes are calculated. Our results show that the Q-markers derived from CMC research strategy can be applied to analyze the manufacturing processes of Chinese medicine to assure product's quality and promote key processes' efficiency simultaneously

Multicomponent ionic liquid CMC prediction.

PubMed

Kłosowska-Chomiczewska, I E; Artichowicz, W; Preiss, U; Jungnickel, C

2017-09-27

We created a model to predict CMC of ILs based on 704 experimental values published in 43 publications since 2000. Our model was able to predict CMC of variety of ILs in binary or ternary system in a presence of salt or alcohol. The molecular volume of IL (V m ), solvent-accessible surface (Ŝ), solvation enthalpy (Δ solv G ∞ ), concentration of salt (C s ) or alcohol (C a ) and their molecular volumes (V ms and V ma , respectively) were chosen as descriptors, and Kernel Support Vector Machine (KSVM) and Evolutionary Algorithm (EA) as regression methodologies to create the models. Data was split into training and validation set (80/20) and subjected to bootstrap aggregation. KSVM provided better fit with average R 2 of 0.843, and MSE of 0.608, whereas EA resulted in R 2 of 0.794 and MSE of 0.973. From the sensitivity analysis it was shown that V m and Ŝ have the highest impact on ILs micellization in both binary and ternary systems, however surprisingly in the presence of alcohol the V m becomes insignificant/irrelevant. Micelle stabilizing or destabilizing influence of the descriptors depends upon the additives. Previous attempts at modelling the CMC of ILs was generally limited to small number of ILs in simplified (binary) systems. We however showed successful prediction of the CMC over a range of different systems (binary and ternary).

Sub-CMC solubilization of dodecane by rhamnolipid in saturated porous media

NASA Astrophysics Data System (ADS)

Yang, X.; Zhong, H.; Zhang, H.; Brusseau, M. L.

2016-12-01

Sub-CMC solubilization of dodecane by rhamnolipid in saturated porous mediaXin Yang1,Hua Zhong1, 2, 3 *, Hui Zhang1, Mark L Brusseau31 College of Environmental Science and Engineering, Hunan University, Changsha 410082, China;2 School of Water Resources and Hydropower Engineering, Wuhan University, Wuhan 430072, China;3 Department of Soil, Water and Environmental Science, University of Arizona, Tucson, Arizona 85721;*Corresponding author, E-mail: zhonghua@hnu.edu.cn, Tel: +86-731-88664182Purpose: Investigate solubilization of dodecane by monorhamnolipid at sub-CMC concentrations in porous media under dynamic flow conditions. Testify aggregate formation mechanism for the solubilization. Methods:One-dimension column experiment was implemented to test dodecane solubilization in glass beads by rhamnolipid at sub-CMC concentrations, and the effect of solubilization on the residual NAPL morphology was examined using X-ray tomography. A two-dimension flow cell was used to examine mobilization and solubilization of dodecane in quartz sand by sub-CMC rhamnolipid. The result of solubilization was compared to that of two synthetic surfactants, SDBS and Triton X-100, and a solvent, ethanol. Size, zeta potential and the morphology of particles in the effluent were also examined. Results: Results of the column and 2-D flow cell studies show enhancement of dodecane solubility by sub-CMC monorhamnolipid in the porous medium. Retention of rhamnolipid and detection of nano-size aggregates show that the solubilization is based on a sub-CMC aggregate-formation mechanism. The rhamnolipid is more efficient for the solubilization compared to the synthetic surfactants and ethanol, and significant solubilization could occur at a rhamnolipid concentration that did not cause mobilization. Conclusions:Results of the study demonstrate the aggregate-based solubilization of dodecane in porous media by rhamnolipid at sub-CMC concentrations. These results indicate a strategy of employing low

The reactivity of Fe/Ni colloid stabilized by carboxymethylcellulose (CMC-Fe/Ni) toward chloroform.

PubMed

Jin, Xin; Li, Qun; Yang, Qi

2018-05-16

The use of stabilizers can prevent the reactivity loss of nanoparticles due to aggregation. In this study, carboxymethylcellulose (CMC) was selected as the stabilizer to synthesize a highly stable CMC-stabilized Fe/Ni colloid (CMC-Fe/Ni) via pre-aggregation stabilization. The reactivity of CMC-Fe/Ni was evaluated via the reaction of chloroform (CF) degradation. The effect of background solution which composition was affected by the preparation of Fe/Ni (Fe/Ni precursors, NaBH 4 dosage) and the addition of solute (common ions, sulfur compounds) on the reactivity of CMC-Fe/Ni was also investigated. Additionally, the dried CMC-Fe/Ni was used for characterization in terms of scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The experimental results indicated that CMC stabilization greatly improved the reactivity of Fe/Ni bimetal and CF (10 mg/L) could be completely degraded by CMC-Fe/Ni (0.1 g/L) within 45 min. The use of different Fe/Ni precursors resulting in the variations of background solution seemed to have no obvious influence on the reactivity of CMC-Fe/Ni, whereas the dosage of NaBH 4 in background solution showed a negative correlation with the reactivity of CMC-Fe/Ni. Besides, the individual addition of external solutes into background solution all had an adverse effect on the reactivity of CMC-Fe/Ni, of which the poisoning effect of sulfides (Na 2 S, Na 2 S 2 O 4 ) was significant than common ions and sulfite.

Active Oxidation of a UHTC-Based CMC

NASA Technical Reports Server (NTRS)

Glass, David E.; Splinter, Scott C.

2012-01-01

The active oxidation of ceramic matrix composites (CMC) is a severe problem that must be avoided for multi-use hypersonic vehicles. Much work has been performed studying the active oxidation of silicon-based CMCs such as C/SiC and SiC-coated carbon/carbon (C/C). Ultra high temperature ceramics (UTHC) have been proposed as a possible material solution for high-temperature applications on hypersonic vehicles. However, little work has been performed studying the active oxidation of UHTCs. The intent of this paper is to present test data indicating an active oxidation process for a UHTC-based CMC similar to the active oxidation observed with Si-based CMCs. A UHTC-based CMC was tested in the HyMETS arc-jet facility (or plasma wind tunnel, PWT) at NASA Langley Research Center, Hampton, VA. The coupon was tested at a nominal surface temperature of 3000 F (1650 C), with a stagnation pressure of 0.026 atm. A sudden and large increase in surface temperature was noticed with negligible increase in the heat flux, indicative of the onset of active oxidation. It is shown that the surface conditions, both temperature and pressure, fall within the region for a passive to active transition (PAT) of the oxidation.

Managing CMC-Based Task through Text-Based Dialogue: An Exploratory Study in a Chinese EFL Context

ERIC Educational Resources Information Center

Yu, Lianfen; Zeng, Gang

2011-01-01

This paper examines EFL learners' dialogic interaction in the implementation of a computer-mediated communication (CMC) task. Within the framework of sociocultural theory, the research focuses on how learners working in pairs collaboratively perform task management and build relationship in the synchronous CMC context. Sixteen Chinese tertiary EFL…

Ceramic Matrix Composites (CMC) Life Prediction Method Development

NASA Technical Reports Server (NTRS)

Levine, Stanley R.; Calomino, Anthony M.; Ellis, John R.; Halbig, Michael C.; Mital, Subodh K.; Murthy, Pappu L.; Opila, Elizabeth J.; Thomas, David J.; Thomas-Ogbuji, Linus U.; Verrilli, Michael J.

2000-01-01

Advanced launch systems (e.g., Reusable Launch Vehicle and other Shuttle Class concepts, Rocket-Based Combine Cycle, etc.), and interplanetary vehicles will very likely incorporate fiber reinforced ceramic matrix composites (CMC) in critical propulsion components. The use of CMC is highly desirable to save weight, to improve reuse capability, and to increase performance. CMC candidate applications are mission and cycle dependent and may include turbopump rotors, housings, combustors, nozzle injectors, exit cones or ramps, and throats. For reusable and single mission uses, accurate prediction of life is critical to mission success. The tools to accomplish life prediction are very immature and not oriented toward the behavior of carbon fiber reinforced silicon carbide (C/SiC), the primary system of interest for a variety of space propulsion applications. This paper describes an approach to satisfy the need to develop an integrated life prediction system for CMC that addresses mechanical durability due to cyclic and steady thermomechanical loads, and takes into account the impact of environmental degradation.

Approaches to polymer-derived CMC matrices

NASA Technical Reports Server (NTRS)

Hurwitz, Frances I.

1992-01-01

The use of polymeric precursors to ceramics permits the fabrication of large, complex-shaped ceramic matrix composites (CMC's) at temperatures which do not degrade the fiber. Processing equipment and techniques readily available in the resin matrix composite industry can be adapted for CMC fabrication using this approach. Criteria which influence the choice of candidate precursor polymers, the use of fillers, and the role of fiber architecture and ply layup are discussed. Three polymer systems, polycarbosilanes, polysilazanes, and polysilsesquioxanes, are compared as candidate ceramic matrix precursors.

Preparation of CMC-modified melamine resin spherical nano-phase change energy storage materials.

PubMed

Hu, Xiaofeng; Huang, Zhanhua; Zhang, Yanhua

2014-01-30

A novel carboxymethyl cellulose (CMC)-modified melamine-formaldehyde (MF) phase change capsule with excellent encapsulation was prepared by in situ polymerization. Effects of CMC on the properties of the capsules were studied by Fourier transformation infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electronic microscopy (SEM), X-ray diffractometry (XRD), and thermogravimetric analysis (TGA). The results showed that the CMC-modified capsules had an average diameter of about 50nm and good uniformity. The phase change enthalpy of the capsules was increased and the cracking ratio decreased by incorporating a suitable amount of CMC. The optimum phase change enthalpy of the nanocapsules was 83.46J/g, and their paraffin content was 63.1%. The heat resistance of the capsule shells decreased after CMC modification. In addition, the nanocapsule cracking ratio of the nanocapsules was 11.0%, which is highly attractive for their application as nano phase change materials. Copyright © 2013 Elsevier Ltd. All rights reserved.

Multilayering of Calcium Aerosol-OT at the Mica/Water Interface Studied with Neutron Reflection: Formation of a Condensed Lamellar Phase at the CMC.

PubMed

Griffin, L R; Browning, K L; Lee, S Y; Skoda, M W A; Rogers, S; Clarke, S M

2016-12-13

Using specular neutron reflection, the adsorption of sodium and calcium salts of the surfactant bis(2-ethylhexyl) sulfosuccinate (Aerosol-OT or AOT) has been studied at the mica/water interface at concentrations between 0.1 and 2 CMC. The pH dependence of the adsorption was also probed. No evidence of the adsorption of Na(AOT) was found even at the critical micelle concentration (CMC) while the calcium salt was found to adsorb significantly at concentrations of 0.5 CMC and above. This interesting and somewhat unexpected finding demonstrates that counterion identity may be used to tune the adsorption of anionic surfactants on anionic surfaces. At the CMC, three condensed bilayers of Ca(AOT) 2 were adsorbed at pH 7 and 9 and four bilayers adsorbed at pH 4. Multilayering at the CMC of Ca(AOT) 2 on the mica surface is an unusual feature of this surfactant/surface combination. Only single bilayer adsorption has been observed at other surfaces at the CMC. We suggest this arises from the high charge density of mica which must provide an excellent template for the surfactant.

Attachment of Free Filament Thermocouples for Temperature Measurements on CMC

NASA Technical Reports Server (NTRS)

Lei, Jih-Fen; Cuy, Michael D.; Wnuk, Stephen P.

1997-01-01

Ceramic Matrix Composites (CMC) are being developed for use as enabling materials for advanced aeropropulsion engine and high speed civil transport applications. The characterization and testing of these advanced materials in hostile, high-temperature environments require accurate measurement of the material temperatures. Commonly used wire Thermo-Couples (TC) can not be attached to this ceramic based material via conventional spot-welding techniques. Attachment of wire TC's with commercially available ceramic cements fail to provide sufficient adhesion at high temperatures. While advanced thin film TC technology provides minimally intrusive surface temperature measurement and has good adhesion on the CMC, its fabrication requires sophisticated and expensive facilities and is very time consuming. In addition, the durability of lead wire attachments to both thin film TC's and the substrate materials requires further improvement. This paper presents a newly developed attachment technique for installation of free filament wire TC's with a unique convoluted design on ceramic based materials such as CMC's. Three CMC's (SiC/SiC CMC and alumina/alumina CMC) instrumented with type IC, R or S wire TC's were tested in a Mach 0.3 burner rig. The CMC temperatures measured from these wire TC's were compared to that from the facility pyrometer and thin film TC's. There was no sign of TC delamination even after several hours exposure to 1200 C. The test results proved that this new technique can successfully attach wire TC's on CMC's and provide temperature data in hostile environments. The sensor fabrication process is less expensive and requires very little time compared to that of the thin film TC's. The same installation technique/process can also be applied to attach lead wires for thin film sensor systems.

Aggregate-based sub-CMC Solubilization of n-Alkanes by Monorhamnolipid Biosurfactant.

PubMed

Zhong, Hua; Yang, Xin; Tan, Fei; Brusseau, Mark L; Yang, Lei; Liu, Zhifeng; Zeng, Guangming; Yuan, Xingzhong

2016-03-01

Solubilization of n -decane, dodecane, tetradecane and hexadecane by monorhamnolipid biosurfactant (monoRL) at concentrations near the critical micelle concentration (CMC) was investigated. The apparent solubility of all the four alkanes increases linearly with increasing monoRL concentration either below or above CMC. The capacity of solubilization presented by the molar solubilization ratio (MSR), however, is stronger at monoRL concentrations below CMC than above CMC. The MSR decreases following the order dodecane > decane > tetradecane > hexadecane at monoRL concentration below CMC. Formation of aggregates at sub-CMC monoRL concentrations was demonstrated by dynamic light scattering (DLS) and cryo-transmission electron microscopy examination. DLS-based size ( d ) and zeta potential of the aggregates decrease with increasing monoRL concentration. The surface excess ( Γ ) of monoRL calculated based on alkane solubility and aggregate size data increases rapidly with increasing bulk monoRL concentration, and then asymptotically approaches the maximum surface excess ( Γ max ). Relation between Γ and d indicates that the excess of monoRL molecules at the aggregate surface greatly impacts the surface curvature. The results demonstrate formation of aggregates for alkane solubilization at monoRL concentrations below CMC, indicating the potential of employing low-concentration rhamnolipid for enhanced solubilization of hydrophobic organic compounds.

Computer-Mediated Communication (CMC) in L2 Oral Proficiency Development: A Meta-Analysis

ERIC Educational Resources Information Center

Lin, Huifen

2015-01-01

The ever growing interest in the development of foreign or second (L2) oral proficiency in a computer-mediated communication (CMC) classroom has resulted in a large body of studies looking at both the direct and indirect effects of CMC interventions on the acquisition of oral competences. The present study employed a quantitative meta-analytic…

The dynamic magnetoviscoelastic properties of biomineralized (Fe3O4) PVP-CMC hydrogel

NASA Astrophysics Data System (ADS)

Ray, Ayan; Saha, Nabanita; Saha, Petr

2017-05-01

The Polyvinylpyrrolidone (PVP) and carboxymethylcellulose (CMC) based polymer matrix was used as a template for the preparation of magnetic hydrogel. This freshly prepared PVP-CMC hydrogel template was successfully mineralized by in situ synthesis of magnetic nanoparticles (Fe3O4) via chemical co-precipitation reaction using liquid diffusion method. The present study emphasizes on the rheological behavior of non-mineralized and mineralized PVP-CMC hydrogels. Scanning Electron Microscopy (SEM), transmission electron microscopy (TEM), X-ray Diffraction (XRD) pattern, Fourier transform infrared spectroscopy (FT-TR), Vibrating sample magnetometer (VSM) and dynamic magneto rheometer were used to study the morphological, physical, chemical and magnetic properties of nanoparticle (Fe3O4) filled PVP-CMC hydrogel respectively in order to monitor how Fe3O4 magnetic nanoparticles affects the mechanical properties of the hydrogel network. The storage (G') and loss (G") moduli with a complex viscosity of the system was measured using a parallel plate rheometer. Frequency and amplitude sweep with temperature variation was performed to determine the frequency and amplitude dependent magneto viscoelastic moduli for both hydrogel samples. A strong shear thinning effect was observed in both (non-mineralized and mineralized) PVP-CMC hydrogels, which confirm that Fe3O4 filled magnetic hydrogels, are pseudoplastic in nature. This Fe3O4 filled PVP-CMC hydrogel can be considered as stimuli-responsive soft matter that may be used as an actuator in medical devices.

Short- and long-term efficiency of carboxymethylcellulose (CMC) to prevent crystal formation in South African wine.

PubMed

Greeff, A E; Robillard, B; du Toit, W J

2012-01-01

Crystal formation in bottled wine occurs due to the over-saturation of wine with potassium bitartrate (KHT) salt when exposed to low temperatures. In this study, special focus was given to the efficiency of a crystallisation-inhibiting additive, carboxymethylcellulose (CMC), which is widely used in the food industry. In 2008, CMC was authorised by the International Organisation of Vine and Wine (OIV) for use in white and sparkling wines, but is not yet officially permitted in all wine-producing countries. The use of CMC could be of economical importance to the wine industry because energy costs due to cooling can be reduced. Unlike traditional cooling methods, the use of CMC theoretically prevents the loss of acidity. In this study, the short- and long-term efficiencies of CMC were investigated in South African white, rosé and red wines. Efficiency was determined primarily by measuring changes in potassium (K(+)) and tartaric acid (H(2)T) concentrations and visual crystal formation. As part of this study CMC's efficiency was compared with several other crystal inhibition treatments, and was also evaluated for its temperature stability over a year. CMC's effect on colour and total phenols was also assessed. The results reveal a high efficiency in preventing losses in K(+) and H(2)T concentrations in white wines, even with an ageing period of up to 12 months. The addition of CMC to rosé wines also delivered certain positive results, but less so for red wine. Three different commercial CMCs were also compared with mannoproteins to prevent changes in K(+) and H(2)T concentrations in three different wines. Furthermore, sensory evaluation was performed to determine certain organoleptic changes as a result of CMC treatments.

Biodegradation of PVP-CMC hydrogel film: a useful food packaging material.

PubMed

Roy, Niladri; Saha, Nabanita; Kitano, Takeshi; Saha, Petr

2012-06-20

Hydrogels can offer new opportunities for the design of efficient packaging materials with desirable properties (i.e. durability, biodegradability and mechanical strength). It is a promising and emerging concept, as most of the biopolymer based hydrogels are supposed to be biodegradable, they can be considered as alternative eco-friendly packaging materials. This article reports about synthetic (polyvinylpyrrolidone (PVP)) and biopolymer (carboxymethyl cellulose (CMC)) based a novel hydrogel film and its nature of biodegradability under controlled environmental condition. The dry hydrogel films were prepared by solution casting method and designated as 'PVP-CMC hydrogel films'. The hydrogel film containing PVP and CMC in a ratio of 20:80 shows best mechanical properties among all the test samples (i.e. 10:90, 20:80, 50:50, 80:20 and 90:10). Thus, PVP-CMC hydrogel film of 20:80 was considered as a useful food packaging material and further experiments were carried out with this particular hydrogel film. Biodegradation of the PVP-CMC hydrogel films were studied in liquid state (Czapec-Dox liquid medium+soil extracts) until 8 weeks. Variation in mechanical, viscoelastic properties and weight loss of the hydrogel films with time provide the direct evidence of biodegradation of the hydrogels. About 38% weight loss was observed within 8 weeks. FTIR spectra of the hydrogel films (before and after biodegradation) show shifts of the peaks and also change in the peak intensities, which refer to the physico-chemical change in the hydrogel structure and SEM views of the hydrogels show how internal structure of the PVP-CMC film changes in the course of biodegradation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mechanism of interactions between CMC binder and Si single crystal facets.

PubMed

Vogl, U S; Das, P K; Weber, A Z; Winter, M; Kostecki, R; Lux, S F

2014-09-02

Interactions of the active material particles with the binder are crucial in tailoring the properties of composite electrodes used in lithium-ion batteries. The dependency of the protonation degree of the carboxyl group in the carboxymethyl cellulose (CMC) structure on the pH value of the preparation solution was investigated by Fourier transform infrared spectroscopy (FTIR). Three different distinctive chemical states of CMC binder were chosen (protonated, deprotonated, and half-half), and their interactions with different silicon single crystal facets were investigated. The different Si surface orientations display distinct differences of strength of interactions with the CMC binder. The CMC/Si adhesion forces in solution and Si wettability of the silicon are also strongly dependent on the protonation degree of the CMC. This work provides an insight into the nature of these interactions, which determine the electrochemical performance of silicon composite electrodes.

Exploring the usefulness of comprehensive care plans for children with medical complexity (CMC): a qualitative study.

PubMed

Adams, Sherri; Cohen, Eyal; Mahant, Sanjay; Friedman, Jeremy N; Macculloch, Radha; Nicholas, David B

2013-01-19

The Medical Home model recommends that Children with Special Health Care Needs (CSHCN) receive a medical care plan, outlining the child's major medical issues and care needs to assist with care coordination. While care plans are a primary component of effective care coordination, the creation and maintenance of care plans is time, labor, and cost intensive, and the desired content of the care plan has not been studied. The purpose of this qualitative study was to understand the usefulness and desired content of comprehensive care plans by exploring the perceptions of parents and health care providers (HCPs) of children with medical complexity (CMC). This qualitative study utilized in-depth semi-structured interviews and focus groups. HCPs (n = 15) and parents (n = 15) of CMC who had all used a comprehensive care plan were recruited from a tertiary pediatric academic health sciences center. Themes were identified through grounded theory analysis of interview and focus group data. A multi-dimensional model of perceived care plan usefulness emerged. The model highlights three integral aspects of the care plan: care plan characteristics, activating factors and perceived outcomes of using a care plan. Care plans were perceived as a useful tool that centralized and focused the care of the child. Care plans were reported to flatten the hierarchical relationship between HCPs and parents, resulting in enhanced reciprocal information exchange and strengthened relationships. Participants expressed that a standardized template that is family-centered and includes content relevant to both the medical and social needs of the child is beneficial when integrated into overall care planning and delivery for CMC. Care plans are perceived to be a useful tool to both health care providers and parents of CMC. These findings inform the utility and development of a comprehensive care plan template as well as a model of how and when to best utilize care plans within family-centered models

Methodological Hurdles in Capturing CMC Data: The Case of the Missing Self-Repair

ERIC Educational Resources Information Center

Smith, Bryan

2008-01-01

This paper reports on a study of the use of self-repair among learners of German in a task-based CMC environment. The purpose of the study was two-fold. The first goal sought to establish how potential interpretations of CMC data may be very different depending on the method of data collection and evaluation employed. The second goal was to…

The use of the Artelon CMC Spacer for osteoarthritis of the basal joint of the thumb.

PubMed

Richard, Marc J; Lunich, Julie A; Correll, Gretchen R

2014-01-01

Favorable clinical outcomes have been reported with the Artelon CMC Spacer, however, several studies have documented complications with the device. The purpose of this study is to review a single surgeon's experience with the Artelon CMC Spacer for the treatment of basal joint arthritis of the thumb. Five thumbs in 6 patients with symptomatic osteoarthritis of the thumb carpometacarpal (CMC) joint were treated with the Artelon CMC Spacer. The mean age of the patients was 60.8 years old. Patients were followed for a mean of 39.3 months (6-63) post-operatively. Complications occurred in 4 of the 6 thumbs and half of the thumbs required at least one secondary operative procedure. A documented foreign-body reaction was present in 2 of the 6 thumbs. The Artelon CMC Spacer is an interposition material that acts as a biologic spacer for arthritic joints while maintaining mechanical strength. Due to an unacceptably high complication rate, we no longer use the Artelon CMC Spacer for the management of basal joint arthritis of the thumb. 4. Copyright © 2014 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Postoperative Therapy for Chronic Thumb Carpometacarpal (CMC) Joint Dislocation.

PubMed

Wollstein, Ronit; Michael, Dafna; Harel, Hani

2016-01-01

Surgical arthroplasty of thumb carpometacarpal (CMC) joint osteoarthritis is commonly performed. Postoperative therapeutic protocols aim to improve range of motion and function of the revised thumb. We describe a case in which the thumb CMC joint had been chronically dislocated before surgery, with shortening of the soft-tissue dynamic and static stabilizers of the joint. The postoperative protocol addressed the soft tissues using splinting and exercises aimed at lengthening and strengthening these structures, with good results. It may be beneficial to evaluate soft-tissue tension and the pattern of thumb use after surgery for thumb CMC joint osteoarthritis to improve postoperative functional results. Copyright © 2016 by the American Occupational Therapy Association, Inc.

CMC Research at NASA Glenn in 2014: Recent Progress and Plans

NASA Technical Reports Server (NTRS)

Grady, Joseph E.

2014-01-01

As part of NASA's Aeronautical Sciences project, Glenn Research Center has developed advanced fiber and matrix constituents for a 2700F CMC for turbine engine applications. Fiber, matrix and CMC development activities will be reviewed and the improvements in the properties and durability of each will be summarized. Plans for 2014 will be summarized, including fabrication and durability testing of the 2700F CMC and status updates on research collaborations underway with AFRL and DOE

Synthesis and characterization of CMC from water hyacinth for lithium-ion battery applications

NASA Astrophysics Data System (ADS)

Hidayat, Sahrul; Susanty, Riveli, Nowo; Suroto, Bambang Joko; Rahayu, Iman

2018-02-01

Recently, the most dominating power supply on the mobile electronics market are rechargeable Lithium-ion batteries. This is because of a higher energy density and longer lifetime compared to similar rechargeable battery systems. One of the components that determine the performance of a lithium ion battery is the binder material, whether at the anode or the cathode. In commercial batteries, the material used as the binder is Polyvinylidene Difluoride (PVDF), with n-methyl-2-phyrrolidone (NMP) as the solvent. Both are synthetic materials that are expensive, toxic and harmful to the environment. An alternative binder material for lithium-ion battery electrodes is CMC (carboxymethyl cellulose) in a water solvent. CMC is cheaper than PVDF, non-toxic and more environmental friendly. CMC can be synthesized from several types of plants, such as water hyacinth, which is a weed plant with high cellulose content. The synthesis of CMC consists of three main steps, namely 1) the isolation process from water hyacinth, 2) the alkalization and carboxymethylation process and 3) the purification process to obtain CMC in high purity. FTIR characterization of the CMC shows five region of absorption bands. The bands in the region 1330-1400 cm-1 are due to symmetrical deformations of CH2 and OH groups. The ether bonds in CMC occur in the fingerprint region of 1250-1060 cm-1. The presence of new and strong absorption band around 1600 cm-1 is confirmed to the stretching vibration of the carboxyl group (COO-), while the one around 1415 cm-1 is assigned to carboxyl groups as it salts. The broad absorption band above 3400 cm-1 is due to the stretching frequency of the hydroxyl group (-OH). Purity test on three samples (CMC mesh-100, CMC mesh-60 and CMC, mesh-40) gives purity values of 99.89%, 99.99% and 99.89%, respectively. This proves that CMC have actually been formed with high purity.

Reliability and Creep/Fatigue Analysis of a CMC Component

NASA Technical Reports Server (NTRS)

Murthy, Pappu L. N.; Mital, Subodh K.; Gyekenyesi, John Z.; Gyekenyesi, John P.

2007-01-01

High temperature ceramic matrix composites (CMC) are being explored as viable candidate materials for hot section gas turbine components. These advanced composites can potentially lead to reduced weight and enable higher operating temperatures requiring less cooling; thus leading to increased engine efficiencies. There is a need for convenient design tools that can accommodate various loading conditions and material data with their associated uncertainties to estimate the minimum predicted life as well as the failure probabilities of a structural component. This paper presents a review of the life prediction and probabilistic analyses performed for a CMC turbine stator vane. A computer code, NASALife, is used to predict the life of a 2-D woven silicon carbide fiber reinforced silicon carbide matrix (SiC/SiC) turbine stator vane due to a mission cycle which induces low cycle fatigue and creep. The output from this program includes damage from creep loading, damage due to cyclic loading and the combined damage due to the given loading cycle. Results indicate that the trends predicted by NASALife are as expected for the loading conditions used for this study. In addition, a combination of woven composite micromechanics, finite element structural analysis and Fast Probability Integration (FPI) techniques has been used to evaluate the maximum stress and its probabilistic distribution in a CMC turbine stator vane. Input variables causing scatter are identified and ranked based upon their sensitivity magnitude. Results indicate that reducing the scatter in proportional limit strength of the vane material has the greatest effect in improving the overall reliability of the CMC vane.

Injectable CMC/PEI gel as an in vivo scaffold for demineralized bone matrix.

PubMed

Kim, Kyung Sook; Kang, Yun Mi; Lee, Ju Young; Kim, E Sle; Kim, Chun Ho; Min, Byoung Hyun; Lee, Hai Bang; Kim, Jae Ho; Kim, Moon Suk

2009-01-01

A number of materials have been considered as sources of grafts to repair bone defects. Here, we examined the possibility of creating in situ-forming gels from sodium carboxymethylcellulose (CMC) and poly(ethyleneimine) (PEI) for use as an in vivo carrier of demineralized bone matrix (DBM). The interaction between anionic CMC and cationic PEI was examined by evaluating phase transition behavior and viscosity of CMC solutions containing 0-30 wt% PEI. CMC solutions containing 10 wt% PEI exhibited a sol-to-gel phase transition at temperatures greater than 35 degrees C. The phase transition is caused by electrostatic crosslinking of the CMC/PEI solution to form a gel with a three-dimensional network structure. In situ-formed gel implants were successfully fabricated in vivo by simple subcutaneous injection of the CMC/PEI (90/10) solution (with and without DBM) into Fisher rats. The resulting in situ-formed implant maintained its shape for 28 days in vitro and in vivo. Our results show that in situ-forming CMC/PEI gels can serve as a DBM carrier that can be delivered with a minimally invasive procedure.

Viscoplastic properties of laponite-CMC mixes.

PubMed

Tarhini, Z; Jarny, S; Texier, A

2017-04-01

In this dataset, 15 samples of laponite-CMC mixes were realized and their viscoplastic properties are determined. Rheological parameters are then expressed as a function of age and components concentrations.

Effect of carboxymethyl cellulose (CMC) as biopolymers to the edible film sorghum starch hydrophobicity characteristics

NASA Astrophysics Data System (ADS)

Putri, Rr. Dewi Artanti; Setiawan, Aji; Anggraini, Puji D.

2017-03-01

The use of synthetic plastic should be limited because it causes the plastic waste that can not be decomposed quickly, triggering environmental problems. The solution of the plastic usage is the use of biodegradable plastic as packaging which is environmentally friendly. Synthesis of edible film can be done with a variety of components. The component mixture of starch and cellulose derivative products are one of the methods for making edible film. Sorghum is a species of cereal crops containing starch amounted to 80.42%, where the use of sorghum in Indonesia merely fodder. Therefore, sorghum is a potential material to be used as a source of starch synthesis edible film. This research aims to study the characteristics of edible starch films Sorghum and assess the effect of CMC (Carboxymethyl Cellulose) as additional materials on the characteristics of biopolymers edible film produced sorghum starch. This study is started with the production of sorghum starch, then the film synthesizing with addition of CMC (5, 10, 15, 20, and 25% w/w starch), and finally the hydrophobicity characteristics test (water uptake test and water solubility test). The addition of CMC will decrease the percentage of water absorption to the film with lowest level of 65.8% in the degree of CMC in 25% (w/w starch). The addition of CMC also influences the water solubility of film, where in the degree of 25% CMC (w/w starch) the solubility of water was the lowest, which was 28.2% TSM.

The novel calicheamicin-conjugated CD22 antibody inotuzumab ozogamicin (CMC-544) effectively kills primary pediatric acute lymphoblastic leukemia cells.

PubMed

de Vries, J F; Zwaan, C M; De Bie, M; Voerman, J S A; den Boer, M L; van Dongen, J J M; van der Velden, V H J

2012-02-01

We investigated whether the newly developed antibody (Ab) -targeted therapy inotuzumab ozogamicin (CMC-544), consisting of a humanized CD22 Ab linked to calicheamicin, is effective in pediatric primary B-cell precursor acute lymphoblastic leukemia (BCP-ALL) cells in vitro, and analyzed which parameters determine its efficacy. CMC-544 induced dose-dependent cell kill in the majority of BCP-ALL cells, although IC(50) values varied substantially (median 4.8 ng/ml, range 0.1-1000 ng/ml at 48 h). The efficacy of CMC-544 was highly dependent on calicheamicin sensitivity and CD22/CMC-544 internalization capacity of BCP-ALL cells, but hardly on basal and renewed CD22 expression. Although CD22 expression was essential for uptake of CMC-544, a repetitive loop of CD22 saturation, CD22/CMC-544 internalization and renewed CD22 expression was not required to achieve intracellular threshold levels of calicheamicin sufficient for efficient CMC-544-induced apoptosis in BCP-ALL cells. This is in contrast to studies with the comparable CD33 immunotoxin gemtuzumab ozogamicin (Mylotarg) in acute myeloid leukemia (AML) patients, in which complete and prolonged CD33 saturation was required for apoptosis induction. These data suggest that CMC-544 treatment may result in higher response rates in ALL compared with response rates obtained in AML with Mylotarg, and that therefore clinical studies in ALL, preferably with multiple low CMC-544 dosages, are warranted.

CMC Research at NASA Glenn in 2017: Recent Progress and Plans

NASA Technical Reports Server (NTRS)

Grady, Joseph E.

2017-01-01

As part of NASA's Aeronautics research mission, Glenn Research Center has developed advanced constituents for 2700F CMC turbine engine applications. In this presentation, fiber and matrix development and characterization for SiCSiC composites will be reviewed and resulting improvements in CMC durability and mechanical properties will be summarized. Progress toward the development and validation of models predicting the effects of the engine environment on durability of CMC and Environmental Barrier Coatings will be summarized and plans for research and collaborations in 2017 will be summarized.

In situ remediation of hexavalent chromium contaminated soil by CMC-stabilized nanoscale zero-valent iron composited with biochar.

PubMed

Zhang, Runyuan; Zhang, Nuanqin; Fang, Zhanqiang

2018-03-01

In this study, the remediation experiments were performed outdoors in natural conditions. Carboxymethyl cellulose (CMC)-stabilized nanoscale zero-valent iron (CMC-nZVI), biochar (BC) and CMC-stabilized nanoscale zero-valent iron composited with biochar (CMC-nZVI/BC) were synthesized and investigated for their effect on the in situ remediation of hexavalent chromium [Cr(VI)] contaminated soil and the concentration of available iron was tested after the remediation, compared with the untreated soil. The results of toxicity characteristic leaching procedure (TCLP) test showed that CMC-nZVI and CMC-nZVI/BC used as remediation materials could obviously improve the remediation rate of Cr contaminated soil and when the ratio of CMC-nZVI to Fe 0 was 2.5 g/Kg, the leachability of Cr(VI) and Cr total can be reduced by 100% and 95.8% simultaneously. Moreover, sequential extraction procedure (SEP) showed that most exchangeable Cr converted to carbonate-bound and Fe-Mn oxides-bound, reducing the availability and leachability of Cr in the soil.

Development of the Virginia Tech Department of Geosciences MEDL-CMC

NASA Astrophysics Data System (ADS)

Glesener, G. B.

2016-12-01

In 2015 the Virginia Tech Department of Geosciences took a leading role in increasing the level of support for Geoscience instructors by investing in the development of the Geosciences Modeling and Educational Demonstrations Laboratory Curriculum Materials Center (MEDL-CMC). The MEDL-CMC is an innovative curriculum materials center designed to foster new collaborative teaching and learning environments by providing hands-on physical models combined with education technology for instructors and outreach coordinators. The mission of the MEDL-CMC is to provide advanced curriculum material resources for the purpose of increasing and sustaining high impact instructional capacity in STEM education for both formal and informal learning environments. This presentation describes the development methods being used to implement the MEDL-CMC. Major development methods include: (1) adopting a project management system to support collaborations with stakeholders, (2) using a diversified funding approach to achieve financial sustainability and the ability to evolve with the educational needs of the community, and (3) establishing a broad collection of systems-based physical analog models and data collection tools to support integrated sciences such as the geosciences. Discussion will focus on how these methods are used for achieving organizational capacity in the MEDL-CMC and on their intended role in reducing instructor workload in planning both classroom activities and research grant broader impacts.

32 CFR 724.305 - Functions of the CMC and CNO.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 5 2013-07-01 2013-07-01 false Functions of the CMC and CNO. 724.305 Section 724.305 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL... of the CMC and CNO. In the case of Navy, CNMPC, under the CNP, shall discharge responsibilities of...

32 CFR 724.305 - Functions of the CMC and CNO.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Functions of the CMC and CNO. 724.305 Section 724.305 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL... of the CMC and CNO. In the case of Navy, CNMPC, under the CNP, shall discharge responsibilities of...

32 CFR 724.305 - Functions of the CMC and CNO.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 32 National Defense 5 2014-07-01 2014-07-01 false Functions of the CMC and CNO. 724.305 Section 724.305 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL... of the CMC and CNO. In the case of Navy, CNMPC, under the CNP, shall discharge responsibilities of...

32 CFR 724.305 - Functions of the CMC and CNO.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 5 2012-07-01 2012-07-01 false Functions of the CMC and CNO. 724.305 Section 724.305 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL... of the CMC and CNO. In the case of Navy, CNMPC, under the CNP, shall discharge responsibilities of...

32 CFR 724.305 - Functions of the CMC and CNO.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 5 2011-07-01 2011-07-01 false Functions of the CMC and CNO. 724.305 Section 724.305 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL... of the CMC and CNO. In the case of Navy, CNMPC, under the CNP, shall discharge responsibilities of...

Oxide_Oxide Ceramic Matrix Composite (CMC) Exhaust Mixer Development in the NASA Environmentally Responsible Aviation (ERA) Project

NASA Technical Reports Server (NTRS)

Kiser, J. Douglas; Bansal, Narottam P.; Szelagowski, James; Sokhey, Jagdish; Heffernan, Tab; Clegg, Joseph; Pierluissi, Anthony; Riedell, Jim; Wyen, Travis; Atmur, Steven;

Ceramic Matrix Composites (CMC) Life Prediction Development

NASA Technical Reports Server (NTRS)

Levine, Stanley R.; Verrilli, Michael J.; Thomas, David J.; Halbig, Michael C.; Calomino, Anthony M.; Ellis, John R.; Opila, Elizabeth J.

1990-01-01

Advanced launch systems will very likely incorporate fiber reinforced ceramic matrix composites (CMC) in critical propulsion and airframe components. The use of CMC will save weight, increase operating margin, safety and performance, and improve reuse capability. For reusable and single mission use, accurate life prediction is critical to success. The tools to accomplish this are immature and not oriented toward the behavior of carbon fiber reinforced silicon carbide (C/SiC), the primary system of interest for many applications. This paper describes an approach and progress made to satisfy the need to develop an integrated life prediction system that addresses mechanical durability and environmental degradation.

Physical and mechanical properties of gelatin-CMC composite films under the influence of electrostatic interactions.

PubMed

Esteghlal, Sara; Niakousari, Mehrdad; Hosseini, Seyed Mohammad Hashem

2018-07-15

The objective of current study was to examine the electrostatic interactions between gelatin and carboxymethyl cellulose (CMC) as a function of pH and mixing ratio (MR) and to observe how the physical and mechanical properties of gelatin-CMC composite films are affected by these interactions. The interaction between biopolymers was studied using turbidometric analysis at different gelatin: CMC MRs and pH values. A reduction in pH and MR enhanced the electrostatic interactions; while, decreased the relative viscosity of mixed system. Physical and mechanical properties of resultant composite films were examined and compared with those of control gelatin films. Changes in the intensity of interactions between the two biopolymers resulted in films with different properties. Polymer complexation led to formation of resistant film networks of less solubility and swellability. Water vapor permeability (WVP) was not significantly (P≤0.05) influenced by incorporating CMC into continuous gelatin films. Composite films prepared at MR of 9:1 and pH opt (corresponding to the maximum amount of interaction) revealed different characteristics such as maximum amounts of WVP and swelling and minimum amounts of tensile strength and solubility. FTIR spectra of composite films confirmed that gelatin and CMC were not covalently bonded. Copyright © 2018 Elsevier B.V. All rights reserved.

Experimental And Numerical Study Of CMC Leading Edges In Hypersonic Flows

NASA Astrophysics Data System (ADS)

Kuhn, Markus; Esser, Burkard; Gulhan, Ali; Dalenbring, Mats; Cavagna, Luca

2011-05-01

Future transportation concepts aim at high supersonic or hypersonic speeds, where the formerly sharp boundaries between aeronautic and aerospace applications become blurred. One of the major issues involved to high speed flight are extremely high aerothermal loads, which especially appear at the leading edges of the plane’s wings and at sharp edged air intake components of the propulsion system. As classical materials like metals or simple ceramics would thermally and structurally fail here, new materials have to be applied. In this context, lightweight ceramic matrix composites (CMC) seem to be prospective candidates as they are high-temperature resistant and offer low thermal expansion along with high specific strength at elevated temperature levels. A generic leading edge model with a ceramic wing assembly with a sweep back angle of 53° was designed, which allowed for easy leading edge sample integration of different CMC materials. The samples consisted of the materials C/C-SiC (non-oxide), OXIPOL and WHIPOX (both oxide) with a nose radius of 2 mm. In addition, a sharp edged C/C-SiC sample was prepared to investigate the nose radius influence. Overall, 13 thermocouples were installed inside the entire model to measure the temperature evolution at specific locations, whereby 5 thermocouples were placed inside the leading edge sample itself. In addition, non-intrusive techniques were applied for surface temperature measurements: An infrared camera was used to measure the surface temperature distribution and at specific spots, the surface temperature was also measured by pyrometers. Following, the model was investigated in DLR’s arc-heated facility L3K at a total enthalpy of 8.5 MJ/kg, Mach number of 7.8, different angles of attack and varying wing inclination angles. These experiments provide a sound basis for the simulation of aerothermally loaded CMC leading edge structures. Such fluid-structure coupled approaches have been performed by FOI, basing on a

CMC determination of nonionic surfactants in protein formulations using ultrasonic resonance technology.

PubMed

Horiuchi, Shohei; Winter, Gerhard

2015-05-01

Biological products often contain surfactants as stabilizers in their formulations to avoid surface adsorption, interfacial denaturation and aggregation of the protein drug and thereby improve the overall pharmaceutical quality of the product. On the other hand, when the surfactant concentration exceeds the critical micelle concentration (CMC) in a protein formulation, protein-loaded micelles could be formed which could potentially be the cause of immunogenicity. Therefore, the actual CMC and the presence of micelles generally need to be confirmed for each protein formulation because the CMC is affected by the presence of protein and other formulation factors. In this study, the ultrasonic resonance technology (URT) was applied to determine CMC of surfactants in pharmaceutical protein solutions in comparison with surface tensiometry (TE) and dynamic light scattering (DLS). According to our results, the ultrasonic resonance technology can easily and precisely provide CMCs of surfactants in protein formulations while it is not working for protein-free formulations. This indicates that the signal we measure with ultrasonic velocity comes from complex micelles composed of surfactant and protein molecules. DLS did not provide reliable data for protein/surfactant systems. Interestingly, a protein formulation with arginine and polysorbate 20 behaved differently when studied with TE and URT allowing us to see that arginine is bound to protein and that the complex interacts with the surfactant. Copyright © 2015 Elsevier B.V. All rights reserved.

Overview of CMC Research at NASA Glenn Research Center

NASA Technical Reports Server (NTRS)

Grady, Joseph E.

2011-01-01

CMC technology development in the Ceramics Branch at NASA Glenn Research Center addresses Aeronautics propulsion goals across subsonic, supersonic and hypersonic flight regimes. Combustor, turbine and exhaust nozzle applications of CMC materials will enable NASA to demonstrate reduced fuel consumption, emissions, and noise in advanced gas turbine engines. Applications ranging from basic Fundamental Aeronautics research activities to technology demonstrations in the new Integrated Systems Research Program will be discussed.

Thin-walled reinforcement lattice structure for hollow CMC buckets

DOEpatents

de Diego, Peter

2017-06-27

A hollow ceramic matrix composite (CMC) turbine bucket with an internal reinforcement lattice structure has improved vibration properties and stiffness. The lattice structure is formed of thin-walled plies made of CMC. The wall structures are arranged and located according to high stress areas within the hollow bucket. After the melt infiltration process, the mandrels melt away, leaving the wall structure to become the internal lattice reinforcement structure of the bucket.

Analyzing CMC Content for What?

ERIC Educational Resources Information Center

Naidu, Som; Jarvela, Sanna

2006-01-01

Computer mediated communication (CMC) refers to communication between individuals and among groups via networked computers. Such forms of communication can be "asynchronous" or "synchronous" and serve a wide variety of useful functions ranging from administration to building understanding and knowledge. As such there are many reasons for interest…

CMC Technologies for Teaching Foreign Languages: What's on the Horizon?

ERIC Educational Resources Information Center

Lafford, Peter A.; Lafford, Barbara A.

2005-01-01

Computer-mediated communication (CMC) technologies have begun to play an increasingly important role in the teaching of foreign/second (L2) languages. Its use in this context is supported by a growing body of CMC research that highlights the importance of the negotiation of meaning and computer-based interaction in the process of second language…

Radiation synthesis of superabsorbent CMC based hydrogels for agriculture applications

NASA Astrophysics Data System (ADS)

Raafat, Amany I.; Eid, Mona; El-Arnaouty, Magda B.

2012-07-01

A series of superabsorbent hydrogel based on carboxymethylcellulose (CMC) and polyvinylpyrrolidone (PVP) crosslinked with gamma irradiation have been proposed for agriculture application. The effect of preparation conditions such as feed solution composition and absorbed irradiation dose on the gelation and swelling degree was evaluated. The structure and the morphology of the superabsorbent CMC/PVP hydrogel were characterized using Fourier transform infrared spectroscopy technique (FTIR), and scanning electron microscope (SEM). Effect of ionic strength and cationic and anionic kinds on the swelling behavior of the obtained hydrogel was investigated. Urea as an agrochemical model was loaded onto the obtained hydrogel to provide nitrogen (N) nutrients. The water retention capability and the urea release behavior of the CMC/PVP hydrogels were investigated. It was found that, the obtained CMC/PVP hydrogels have good swelling degree that greatly affected by its composition and absorbed dose. The swelling was also extremely sensitive to the ionic strength and cationic kind. Owing to its considerable slow urea release, good water retention capacity, being economical, and environment-friendly, it might be useful for its application in agriculture field.

A Meta-Synthesis of Empirical Research on the Effectiveness of Computer-Mediated Communication (CMC) in SLA

ERIC Educational Resources Information Center

Lin, Huifen

2015-01-01

This meta-analysis reports the results of a systematic synthesis of primary studies on the effectiveness of computer-mediated communication (CMC) in second language acquisition (SLA) for the period 2000-2012. By extracting information on 21 features from each primary study, this meta-analysis intends to summarize the CMC research literature for…

Lightweight, Ultra-High-Temperature, CMC-Lined Carbon/Carbon Structures

NASA Technical Reports Server (NTRS)

Wright, Matthew J.; Ramachandran, Gautham; Williams, Brian E.

2011-01-01

Carbon/carbon (C/C) is an established engineering material used extensively in aerospace. The beneficial properties of C/C include high strength, low density, and toughness. Its shortcoming is its limited usability at temperatures higher than the oxidation temperature of carbon . approximately 400 C. Ceramic matrix composites (CMCs) are used instead, but carry a weight penalty. Combining a thin laminate of CMC to a bulk structure of C/C retains all of the benefits of C/C with the high temperature oxidizing environment usability of CMCs. Ultramet demonstrated the feasibility of combining the light weight of C/C composites with the oxidation resistance of zirconium carbide (ZrC) and zirconium- silicon carbide (Zr-Si-C) CMCs in a unique system composed of a C/C primary structure with an integral CMC liner with temperature capability up to 4,200 F (.2,315 C). The system effectively bridged the gap in weight and performance between coated C/C and bulk CMCs. Fabrication was demonstrated through an innovative variant of Ultramet fs rapid, pressureless melt infiltration processing technology. The fully developed material system has strength that is comparable with that of C/C, lower density than Cf/SiC, and ultra-high-temperature oxidation stability. Application of the reinforced ceramic casing to a predominantly C/C structure creates a highly innovative material with the potential to achieve the long-sought goal of long-term, cyclic high-temperature use of C/C in an oxidizing environment. The C/C substructure provided most of the mechanical integrity, and the CMC strengths achieved appeared to be sufficient to allow the CMC to perform its primary function of protecting the C/C. Nozzle extension components were fabricated and successfully hot-fire tested. Test results showed good thermochemical and thermomechanical stability of the CMC, as well as excellent interfacial bonding between the CMC liner and the underlying C/C structure. In particular, hafnium-containing CMCs on

A LES-CMC formulation for premixed flames including differential diffusion

NASA Astrophysics Data System (ADS)

Farrace, Daniele; Chung, Kyoungseoun; Bolla, Michele; Wright, Yuri M.; Boulouchos, Konstantinos; Mastorakos, Epaminondas

2018-05-01

A finite volume large eddy simulation-conditional moment closure (LES-CMC) numerical framework for premixed combustion developed in a previous studyhas been extended to account for differential diffusion. The non-unity Lewis number CMC transport equation has an additional convective term in sample space proportional to the conditional diffusion of the progress variable, that in turn accounts for diffusion normal to the flame front and curvature-induced effects. Planar laminar simulations are first performed using a spatially homogeneous non-unity Lewis number CMC formulation and validated against physical-space fully resolved reference solutions. The same CMC formulation is subsequently used to numerically investigate the effects of curvature for laminar flames having different effective Lewis numbers: a lean methane-air flame with Leeff = 0.99 and a lean hydrogen-air flame with Leeff = 0.33. Results suggest that curvature does not affect the conditional heat release if the effective Lewis number tends to unity, so that curvature-induced transport may be neglected. Finally, the effect of turbulence on the flame structure is qualitatively analysed using LES-CMC simulations with and without differential diffusion for a turbulent premixed bluff body methane-air flame exhibiting local extinction behaviour. Overall, both the unity and the non-unity computations predict the characteristic M-shaped flame observed experimentally, although some minor differences are identified. The findings suggest that for the high Karlovitz number (from 1 to 10) flame considered, turbulent mixing within the flame weakens the differential transport contribution by reducing the conditional scalar dissipation rate and accordingly the conditional diffusion of the progress variable.

[PLA-O-CMC nanoparticles: HGF loading and delivery behaviors in vitro].

PubMed

Li, Zhifeng; Chen, Zhong; Chang, Ren'an

2011-04-01

This paper is aimed to observe the hepatocyte growth factor (HGF) loading and delivery ability of polylactic acid and oxygen carboxymethylated chitosan copolyer nanoparticles (PLA-O-CMC NPs). We prepared PLA-O-CMC NPs loaded with HGF by ultrasound in combination with magnetic stirring method. The NPs were characterized by transmission electron microscopy, embedding ratio; drug loading and drug delivery behaviors were observed by ELISA. The characteristics of PLA-O-CMC NPs loaded with HGF showed that the mean size was 139. 82 nm, polydispersity was 0.108, maximal HGF-embedding ratio was 76. 32%. The cumulative HGF release gradually increased in the first 24 hours in vitro, with sharp increasing in the first 7 hours, and moderate and steady increasing in the following 17 hours. The HGF had a burst release in the first 24 hours, and in this process the released HGF took up 36.7% of the whole release. From the second day,the HGF release decreased obviously, while it kept on releasing steadily (45-55 ng/d) for quite long time up to 30 days. The experiment proved that PLA-O-CMC NPs is a favourable carrier of HGF. PLA-O-CMC NPs loaded with HGF could rapidly release HGF in vitro. The released HGF reached the effective drug concentration and maintained the certain effective drug concentration for a long time.

Optimization of preparation of NDV F Gene encapsulated in N-2-HACC-CMC nanoparticles

NASA Astrophysics Data System (ADS)

Li, S. S.; Zhang, Y.; Zhao, K.; Wang, X. H.

2018-01-01

In this study, the biodegradable materials N-2-hydroxypropyl trimethyl ammonium chloride chitosan (N-2-HACC) and N, O-carboxymethyl chitosan (CMC) are used as delivery carrier for the pVAX I -F(o)-C3d6. The optimal preparation condition is as follows: concentration of N-2-HACC is 1.0 mg/ml, concentration of CMC is 0.85 mg/ml, concentration of pVAX I -F(o)-C3d6 is 100 μg ml. The results show that the prepared N-2-HACC-CMC/pFDNA NPs have regular round shape, smooth surface and good dispersion, the particle size is 310 nm, Zeta potential is 50 mV, the entrapment efficiency is 92 %, the loading capacity is 51 % (n=3).

Structural reliability analysis of laminated CMC components

NASA Technical Reports Server (NTRS)

Duffy, Stephen F.; Palko, Joseph L.; Gyekenyesi, John P.

1991-01-01

For laminated ceramic matrix composite (CMC) materials to realize their full potential in aerospace applications, design methods and protocols are a necessity. The time independent failure response of these materials is focussed on and a reliability analysis is presented associated with the initiation of matrix cracking. A public domain computer algorithm is highlighted that was coupled with the laminate analysis of a finite element code and which serves as a design aid to analyze structural components made from laminated CMC materials. Issues relevant to the effect of the size of the component are discussed, and a parameter estimation procedure is presented. The estimation procedure allows three parameters to be calculated from a failure population that has an underlying Weibull distribution.

Development of a Hydrogen Uptake-Release Mg-Based Alloy by Adding a Polymer CMC (Carboxymethylcellulose, Sodium Salt) via Reaction-Accompanying Milling

NASA Astrophysics Data System (ADS)

Kwak, Young Jun; Choi, Eunho; Song, Myoung Youp

2018-03-01

The addition of carboxymethylcellulose, sodium salt (CMC) might improve the hydrogen uptake and release properties of Mg since it has a relatively low melting point and the melting of CMC during milling in hydrogen (reaction-accompanying milling) may make the milled samples be in good states to absorb and release hydrogen rapidly and to have a large hydrogen-storage capacity. Samples with compositions of 95 w/o Mg + 5 w/o CMC (named Mg-5CMC) and 90 w/o Mg + 10 w/o CMC (named Mg-10CMC) were prepared by adding CMC via reaction-accompanying milling. Activation of Mg-10CMC was completed after about 3 hydrogen uptake-release cycles. Mg-10CMC had a higher initial hydrogen uptake rate and a larger amount of hydrogen absorbed in 60 min, U (60 min), than Mg-5CMC before and after activation. At the cycle number of three (CN = 3), Mg-10CMC had a very high initial hydrogen uptake rate (1.56 w/o H/min) and a large U (60 min) (5.57 w/o H) at 593 K in hydrogen of 12 bar, showing that the activated Mg-10CMC has an effective hydrogen-storage capacity of about 5.6 w/o at 593 K in hydrogen of 12 bar at CN = 3. At CN = 2, Mg-10CMC released 1.00 w/o H in 2.5 min, 4.67 w/o H in 10 min, and 4.76 w/o H in 60 min at 648 K in hydrogen of 1.0 bar. The milling in hydrogen of Mg with CMC is believed to generate imperfections and cracks and reduce the particle size. The addition of 10 w/o CMC was more effective on the initial hydrogen uptake rate and U (60 min) compared with the 10 w/o additions of NbF5, TaF5, Fe2O3, and MnO, and the 10 w/o simultaneous addition of Ni, Fe, and Ti. To the best of our knowledge, this study is the first in which a polymer CMC is added to Mg by reaction-accompanying milling to improve the hydrogen storage properties of Mg.

Simulations of spray autoignition and flame establishment with two-dimensional CMC

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

Wright, Y.M.; Boulouchos, K.; De Paola, G.

2005-12-01

The unsteady two-dimensional conditional moment closure (CMC) model with first-order closure of the chemistry and supplied with standard models for the conditional convection and turbulent diffusion terms has been interfaced with a commercial engine CFD code and analyzed with two numerical methods, an 'exact' calculation with the method of lines and a faster fractional-step method. The aim was to examine the sensitivity of the predictions to the operator splitting errors and to identify the extent to which spatial transport terms are important for spray autoignition problems. Despite the underlying simplifications, solution of the full CMC equations allows a single modelmore » to be used for the autoignition, flame propagation ('premixed mode'), and diffusion flame mode of diesel combustion, which makes CMC a good candidate model for practical engine calculations. It was found that (i) the conditional averages have significant spatial gradients before ignition and during the premixed mode and (ii) that the inclusion of physical-space transport affects the calculation of the autoignition delay time, both of which suggest that volume-averaged CMC approaches may be inappropriate for diesel-like problems. A balance of terms in the CMC equation before and after autoignition shows the relative magnitude of spatial transport and allows conjectures on the structure of the premixed phase of diesel combustion. Very good agreement with available experimental data is found concerning ignition delays and the effect of background air turbulence on them.« less

CMC vane assembly apparatus and method

DOEpatents

Schiavo, Anthony L; Gonzalez, Malberto F; Huang, Kuangwei; Radonovich, David C

2012-10-23

A metal vane core or strut (64) is formed integrally with an outer backing plate (40). An inner backing plate (38) is formed separately. A spring (74) with holes (75) is installed in a peripheral spring chamber (76) on the strut. Inner and outer CMC shroud covers (46, 48) are formed, cured, then attached to facing surfaces of the inner and outer backing plates (38, 40). A CMC vane airfoil (22) is formed, cured, and slid over the strut (64). The spring (74) urges continuous contact between the strut (64) and airfoil (66), eliminating vibrations while allowing differential expansion. The inner end (88) of the strut is fastened to the inner backing plate (38). A cooling channel (68) in the strut is connected by holes (69) along the leading edge of the strut to peripheral cooling paths (70, 71) around the strut. Coolant flows through and around the strut, including through the spring holes.

Nanocomposite films based on CMC, okra mucilage and ZnO nanoparticles: Physico mechanical and antibacterial properties.

PubMed

Mohammadi, Hamid; Kamkar, Abolfazl; Misaghi, Ali

2018-02-01

This work examined the physico mechanical parameters and antibacterial activity of CMC/okra mucilage (OM) blend films containing ZnO nanoparticles (NPs). Different proportions of CMC and okra mucilage (100/0; 70/30; 60/40 and 50/50 respectively), were mixed and casted to posterior analysis of formed films. The more colored films were obtained by higher contents of okra mucilage and adding ZnO nanoparticles. The incorporation of ZnO NPs into CMC film decreased the elongation at the break (EB) value of the films and increased the tensile strength (TS) value of the film. With increase in CMC concentration in the films, higher water vapor permeability and higher solubility in water were achieved. Microstructure analysis using SEM showed a smooth and compact surface morphology, homogeneous structure, and a rough surface for CMC, CMC+ZnO, and CMC/OM30%+ZnO, respectively. Nanocomposite films presented antibacterial activity against tested bacteria. Films contained okra mucilage showed more antibacterial activity. The inhibitory activities of resultant films were stronger against S. aureus than E. coli. Copyright © 2017 Elsevier Ltd. All rights reserved.

Facile fabrication and characterization of a novel oral pH-sensitive drug delivery system based on CMC hydrogel and HNT-AT nanohybrid.

PubMed

Hossieni-Aghdam, Seyed Jamal; Foroughi-Nia, Behrouz; Zare-Akbari, Zhila; Mojarad-Jabali, Solmaz; Motasadizadeh, Hamidreza; Farhadnejad, Hassan

2018-02-01

The main aim of the present study was to design pH-sensitive bionanocomposite hydrogel beads based on CMC and HNT-AT nanohybrid and evaluate whether prepared bionanocomposite beads have the potential to be used in drug delivery applications. Atenolol (AT), as a model drug, was incorporated into the lumen of HA nanotubes via the co-precipitation technique. HNT/AT nanohybrid and CMC/HNT-AT beads were characterized via XRD, SEM, TGA, and FT-IR techniques. Drug loading and encapsulation efficiency was found to be high for CMC/HNT3 beads. Moreover, the swelling and drug release properties of the prepared CMC/HA-AT beads were investigated, and showed a pH sensitive swelling behavior with maximum its content at pH 6.8. Also, it was found that the swelling ratio of CMC/HNT beads was lower than that of pristine CMC beads. Drug release behavior of CMC/HNT-AT bionanocomposite hydrogel beads were investigated. A more sustained and controlled drug releases were observed for CMC/HNT-AT beads. Copyright © 2017 Elsevier B.V. All rights reserved.

Therapeutic potential of CD22-specific antibody-targeted chemotherapy using inotuzumab ozogamicin (CMC-544) for the treatment of acute lymphoblastic leukemia.

PubMed

Dijoseph, J F; Dougher, M M; Armellino, D C; Evans, D Y; Damle, N K

2007-11-01

CMC-544 (inotuzumab ozogamicin) is a CD22-specific cytotoxic immunoconjugate of calicheamicin intended for the treatment of B-lymphoid malignancies. This preclinical study investigated antitumor activity of CMC-544 against CD22+ acute lymphoblastic leukemia (ALL). CMC-544 inhibited in vitro growth of ALL cell lines more potently than that of Ramos B-lymphoma cells. When administered to nude mice with established sc xenografts of REH ALL, CMC-544 caused dose-dependent inhibition of xenograft growth producing complete tumor regression and cures in tumor-bearing mice at the highest dose of 160 microg/kg of conjugated calicheamicin. In contrast, a nonbinding control conjugate was 16-fold less effective than CMC-544 in inhibiting growth of REH ALL xenografts. When REH cells were injected intravenously in scid mice and allowed to disseminate systemically, mice developed hind-limb paralysis that was effectively prevented by treatment with CMC-544. Flow cytometric analysis of cells recovered from the bone marrow from mice with disseminated disease verified the presence of engrafted ALL cells. Significantly reduced numbers of ALL cells were recovered from the bone marrow of CMC-544-treated mice than from vehicle-treated mice with disseminated disease. The anti-leukemia activity of CMC-544 demonstrated here further supports clinical evaluation of CMC-544 for the treatment of CD22+ leukemia.

Effects of Synchronous and Asynchronous Computer-Mediated Communication (CMC) Oral Conversations on English Language Learners' Discourse Functions

ERIC Educational Resources Information Center

AbuSeileek, Ali Farhan; Qatawneh, Khaleel

2013-01-01

This study aimed to explore the effects of synchronous and asynchronous computer mediated communication (CMC) oral discussions on question types and strategies used by English as a Foreign Language (EFL) learners. The participants were randomly assigned to two treatment conditions/groups; the first group used synchronous CMC, while the second…

Sub-CMC solubilization of dodecane by rhamnolipid in saturated porous media.

PubMed

Zhong, Hua; Zhang, Hui; Liu, Zhifeng; Yang, Xin; Brusseau, Mark L; Zeng, Guangming

2016-09-13

Experiments were conducted with a two-dimensional flow cell to examine the effect of monorhamnolipid surfactant at sub-CMC concentrations on solubilization of dodecane in porous media under dynamic flow conditions. Quartz sand was used as the porous medium and artificial groundwater was used as the background solution. The effectiveness of the monorhamnolipid was compared to that of SDBS, Triton X-100, and ethanol. The results demonstrated the enhancement of dodecane solubility by monorhamnolipid surfactant at concentrations lower than CMC. The concentrations (50-210 μM) are sufficiently low that they do not cause mobilization of the dodecane. Retention of rhamnolipid in the porous medium and detection of nano-size aggregates in the effluent show that the solubilization is based on a sub-CMC aggregate-formation mechanism, which is significantly stronger than the solubilization caused by the co-solvent effect. The rhamnolipid biosurfactant is more efficient for the solubilization compared to the synthetic surfactants. These results indicate a strategy of employing low concentrations of rhamnolipid for surfactant-enhanced aquifer remediation (SEAR), which may overcome the drawbacks of using surfactants at hyper-CMC concentrations.

Thin Film Heat Flux Sensor Development for Ceramic Matrix Composite (CMC) Systems

NASA Technical Reports Server (NTRS)

Wrbanek, John D.; Fralick, Gustave C.; Hunter, Gary W.; Zhu, Dongming; Laster, Kimala L.; Gonzalez, Jose M.; Gregory, Otto J.

2010-01-01

The NASA Glenn Research Center (GRC) has an on-going effort for developing high temperature thin film sensors for advanced turbine engine components. Stable, high temperature thin film ceramic thermocouples have been demonstrated in the lab, and novel methods of fabricating sensors have been developed. To fabricate thin film heat flux sensors for Ceramic Matrix Composite (CMC) systems, the rough and porous nature of the CMC system posed a significant challenge for patterning the fine features required. The status of the effort to develop thin film heat flux sensors specifically for use on silicon carbide (SiC) CMC systems with these new technologies is described.

Apparatus and method to reduce wear and friction between CMC-to-metal attachment and interface

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

Cairo, Ronald Ralph; Parolini, Jason Robert; Delvaux, John McConnell

An apparatus to reduce wear and friction between CMC-to-metal attachment and interface, including a metal layer configured for insertion between a surface interface between a CMC component and a metal component. The surface interface of the metal layer is compliant relative to asperities of the surface interface of the CMC component. A coefficient of friction between the surface interface of the CMC component and the metal component is about 1.0 or less at an operating temperature between about 300.degree. C. to about 325.degree. C. and a limiting temperature of the metal component.

[Preparation of Coated CMC-Fe0 Using Rheological Phase Reaction Method and Research on Degradation of TCE in Water].

PubMed

Fan, Wen-jing; Cheng, Yue; Yu, Shu-zhen; Fan, Xiao-feng

2015-06-01

The coated nanoscale zero-valent iron (coated CMC-Fe0) was synthesized with cheap and environment friendly CMC as the coating agent using rheological phase reaction. The sample was characterized by means of XRD, SEM, TEM and N2 adsorption-stripping and used to study reductive dechlorination of TCE. The experimental results indicated that the removal rate of TCE was about 100% when the CMC-Fe0 dosage was 6 g x L(-1), the initial TCE concentration was 5 mg x L(-1) and the reaction time was 40 h. The TCE degradation reaction of coated CMC-Fe0 followed a pseudo-first-order kinetic model. Finally, the product could be simply recovered.

Complications with the use of Artelon in thumb CMC joint arthritis.

PubMed

Clarke, Sylvan; Hagberg, William; Kaufmann, Robert A; Grand, Aaron; Wollstein, Ronit

2011-09-01

Complications with the use of the Artelon spacer in thumb carpometacarpal (CMC) joint arthritis include inflammation, osteolysis, and persistent pain. We evaluated our short-term results and complications. A retrospective review of 29 patients was performed. Pre- and postoperative radiographs, operative techniques, complications, and subsequent surgeries were analyzed. Pearson's and chi-squared testing was used to identify associations between complications and surgical technique or preoperative radiographic criteria. The average age was age 51 ± 7.7 (34-66), average follow-up was 8 months (1-26). Twelve patients sustained complications. Nine patients displayed postoperative osteolysis. Four patients underwent conversion to CMC suspensionplasty due to persistent pain. The rate of revision surgery and radiographic postoperative osteolysis were not significantly associated with preoperative arthritis grade, metacarpal subluxation, or surgical techniques: fixation method, the bony surface(s) involved in the osteotomy, or spacer modifications. Our study found a significant short-term complication rate following Artelon spacer arthroplasty of the CMC joint. This is higher than previously described. We could not identify any factors that were significantly associated with the complications. It is possible that the inherent instability of the joint or the material of the spacer is involved in implant failure. Further study is necessary to better define the indications for use and specific techniques for the use of the implant.

Power, Voice and Democratization: Feminist Pedagogy and Assessment in CMC.

ERIC Educational Resources Information Center

Campbell, Katy

2002-01-01

Discussion of differences in the ways that female and male faculty approach the use of technology in teaching focuses on a study of female faculty learning design preferences in critical feminist teaching. Considers learner-centered approaches; interactions with students in computer-mediated communication (CMC); democratization in online…

A qualitative study of health care providers' perceptions and experiences of working together to care for children with medical complexity (CMC).

PubMed

Altman, Lisa; Zurynski, Yvonne; Breen, Christie; Hoffmann, Tim; Woolfenden, Susan

2018-01-31

Children with medical complexity (CMC) have a wide range of long term health problems and disabilities that have an adverse impact on their quality of life. They have high levels of family identified health care needs and health care utilisation. There is no Australian literature on the experiences of health care providers working in the Australian tertiary, secondary and primary health care system, whilst managing CMC. This information is essential to inform the design of integrated health care systems for these children. We address this knowledge gap by exploring the perceptions and experiences of health care providers on the provision of health care for CMC aged 0 to 18 years. A qualitative research study was undertaken. Stakeholder forums, group and individual in depth interviews were undertaken using a semi-structured interview guide. The stakeholder forums were audio recorded and transcribed verbatim. Field notes of the stakeholder forums, group and individual interviews were taken. Inductive thematic analysis was undertaken to identify key themes. One hundred and three providers took part in the stakeholder forums and interviews across 3 local health districts, a tertiary paediatric hospital network, and primary health care organisations. Providers expressed concern regarding family capacity to negotiate the system, which was impacted by the medical complexity of the children and psychosocial complexity of their families. Lack of health care provider capacity in terms of their skills, time and availability to manage CMC was also a key problem. These issues occurred within a health system that had impaired capacity in terms of fragmentation of care and limited communication among health care providers. When designing integrated care models for CMC, it is essential to understand and address the challenges experienced by their health care providers. This requires adequate training of providers, additional resources and time for coordination of care, improved

Small deformation viscoelastic and thermal behaviours of pomegranate seed pips CMC gels.

PubMed

Savadkoohi, Sobhan; Farahnaky, Asgar

2015-07-01

The current investigation presents an exploration in phase behaviour of carboxymethyl cellulose (CMC) produced from pomegranate seed pips compared to low and high viscosity CMCs (LMCMC and HMCMC) primarily at low solid concentrations. Cellulose was extracted with 10 % NaOH at 35 °C for 22 h from pomegranate seed pips and converted to CMC by etherification process. Thermomechanical analysis and micro-imaging were carried out using small deformation dynamic oscillation in shear, modulated differential scanning calorimetry (MDSC) and scanning electron microscopy (SEM). The results emphasize the importance of molecular interaction and the degree of substitution in produced CMC. Thermal gravimetric analysis (TGA) thermograms showed an initial weight loss in pomegranate seed pips CMC (PSCMC) sample, which we attribute to presence of amount of moisture in sample powder. MDSC analysis of PSCMC showed five different peaks at 84, 104, 173, 307 and 361 °C. Moreover, G' and G" changes were found to be dependent on both concentration and frequency. The results of frequency sweep and tan δ indicate that PSCMC solutions can be classified as weak gels.

Fired Cartridge Case Identification Using Optical Images and the Congruent Matching Cells (CMC) Method.

PubMed

Tong, Mingsi; Song, John; Chu, Wei; Thompson, Robert M

2014-01-01

The Congruent Matching Cells (CMC) method for ballistics identification was invented at the National Institute of Standards and Technology (NIST). The CMC method is based on the correlation of pairs of small correlation cells instead of the correlation of entire images. Four identification parameters - T CCF, T θ, T x and T y are proposed for identifying correlated cell pairs originating from the same firearm. The correlation conclusion (matching or non-matching) is determined by whether the number of CMC is ≥ 6. This method has been previously validated using a set of 780 pair-wise 3D topography images. However, most ballistic images stored in current local and national databases are in an optical intensity (grayscale) format. As a result, the reliability of applying the CMC method on optical intensity images is an important issue. In this paper, optical intensity images of breech face impressions captured on the same set of 40 cartridge cases are correlated and analyzed for the validation test of CMC method using optical images. This includes correlations of 63 pairs of matching images and 717 pairs of non-matching images under top ring lighting. Tests of the method do not produce any false identification (false positive) or false exclusion (false negative) results, which support the CMC method and the proposed identification criterion, C = 6, for firearm breech face identifications using optical intensity images.

Fired Cartridge Case Identification Using Optical Images and the Congruent Matching Cells (CMC) Method

PubMed Central

Tong, Mingsi; Song, John; Chu, Wei; Thompson, Robert M

2014-01-01

The Congruent Matching Cells (CMC) method for ballistics identification was invented at the National Institute of Standards and Technology (NIST). The CMC method is based on the correlation of pairs of small correlation cells instead of the correlation of entire images. Four identification parameters – TCCF, Tθ, Tx and Ty are proposed for identifying correlated cell pairs originating from the same firearm. The correlation conclusion (matching or non-matching) is determined by whether the number of CMC is ≥ 6. This method has been previously validated using a set of 780 pair-wise 3D topography images. However, most ballistic images stored in current local and national databases are in an optical intensity (grayscale) format. As a result, the reliability of applying the CMC method on optical intensity images is an important issue. In this paper, optical intensity images of breech face impressions captured on the same set of 40 cartridge cases are correlated and analyzed for the validation test of CMC method using optical images. This includes correlations of 63 pairs of matching images and 717 pairs of non-matching images under top ring lighting. Tests of the method do not produce any false identification (false positive) or false exclusion (false negative) results, which support the CMC method and the proposed identification criterion, C = 6, for firearm breech face identifications using optical intensity images. PMID:26601045

CMC-544 (inotuzumab ozogamicin), an anti-CD22 immuno-conjugate of calicheamicin, alters the levels of target molecules of malignant B-cells.

PubMed

Takeshita, A; Yamakage, N; Shinjo, K; Ono, T; Hirano, I; Nakamura, S; Shigeno, K; Tobita, T; Maekawa, M; Kiyoi, H; Naoe, T; Ohnishi, K; Sugimoto, Y; Ohno, R

2009-07-01

We studied the effect of CMC-544, the calicheamicin-conjugated anti-CD22 monoclonal antibody, used alone and in combination with rituximab, analyzing the quantitative alteration of target molecules, that is, CD20, CD22, CD55 and CD59, in Daudi and Raji cells as well as in cells obtained from patients with B-cell malignancies (BCM). Antibody inducing direct antiproliferative and apoptotic effect, complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) were tested separately. In Daudi and Raji cells, the CDC effect of rituximab significantly increased within 12 h following incubation with CMC-544. The levels of CD22 and CD55 were significantly reduced (P<0.001 in both cells) after incubation with CMC-544, but CD20 level remained constant or increased for 12 h. Similar results were obtained in cells from 12 patients with BCM. The antiproliferative and apoptotic effect of CMC-544 were greater than that of rituximab. The ADCC of rituximab was not enhanced by CMC-544. Thus, the combination of CMC-544 and rituximab increased the in vitro cytotoxic effect in BCM cells, and sequential administration for 12 h proceeded by CMC-544 was more effective. The reduction of CD55 and the preservation of CD20 after incubation with CMC-544 support the rationale for the combined use of CMC-544 and rituximab.

Turbine Airfoil With CMC Leading-Edge Concept Tested Under Simulated Gas Turbine Conditions

NASA Technical Reports Server (NTRS)

Robinson, R. Craig; Hatton, Kenneth S.

2000-01-01

Silicon-based ceramics have been proposed as component materials for gas turbine engine hot-sections. When the Navy s Harrier fighter experienced engine (Pegasus F402) failure because of leading-edge durability problems on the second-stage high-pressure turbine vane, the Office of Naval Research came to the NASA Glenn Research Center at Lewis Field for test support in evaluating a concept for eliminating the vane-edge degradation. The High Pressure Burner Rig (HPBR) was selected for testing since it could provide temperature, pressure, velocity, and combustion gas compositions that closely simulate the engine environment. The study focused on equipping the stationary metal airfoil (Pegasus F402) with a ceramic matrix composite (CMC) leading-edge insert and evaluating the feasibility and benefits of such a configuration. The test exposed the component, with and without the CMC insert, to the harsh engine environment in an unloaded condition, with cooling to provide temperature relief to the metal blade underneath. The insert was made using an AlliedSignal Composites, Inc., enhanced HiNicalon (Nippon Carbon Co. LTD., Yokohama, Japan) fiber-reinforced silicon carbide composite (SiC/SiC CMC) material fabricated via chemical vapor infiltration. This insert was 45-mils thick and occupied a recessed area in the leading edge and shroud of the vane. It was designed to be free floating with an end cap design. The HPBR tests provided a comparative evaluation of the temperature response and leading-edge durability and included cycling the airfoils between simulated idle, lift, and cruise flight conditions. In addition, the airfoils were aircooled, uniquely instrumented, and exposed to the exact set of internal and external conditions, which included gas temperatures in excess of 1370 C (2500 F). In addition to documenting the temperature response of the metal vane for comparison with the CMC, a demonstration of improved leading-edge durability was a primary goal. First, the

Effect of a freeze-dried CMC/PLGA microsphere matrix of rhBMP-2 on bone healing.

PubMed

Schrier, J A; Fink, B F; Rodgers, J B; Vasconez, H C; DeLuca, P P

2001-10-07

The hypothesis of this research was that implants of poly(lactide-co-glycolide) (PLGA) microspheres loaded with bone morphogenetic protein-2 (rhBMP-2) and distributed in a freeze-dried carboxymethylcellulose (CMC) matrix would produce more new bone than would matrix implants of non-protein-loaded microspheres or matrix implants of only CMC. To test this hypothesis it was necessary to fashion microsphere-loaded CMC implants that were simple to insert, fit precisely into a defect, and would not elicit swelling. Microspheres were produced via a water-in-oil-in-water double-emulsion system and were loaded with rhBMP-2 by soaking them in a buffered solution of the protein at a concentration of 5.4 mg protein per gram of PLGA. Following recovery of the loaded microspheres by lyophilization, matrices for implantation were prepared by lyophilizing a suspension of the microspheres in 2% CMC in flat-bottom tissue culture plates. Similar matrices were made with 2% CMC and with 2% CMC containing blank microspheres. A full-thickness calvarial defect model in New Zealand white rabbits was used to assess bone growth. Implants fit the defect well, allowing for direct application. Six weeks postsurgery, defects were collected and processed for undecalcified histology. In vitro, 60% of the loaded rhBMP-2 released from devices or microspheres in 5 to 7 days, with the unembedded microspheres releasing faster than those embedded in CMC. In vivo, the rhBMP-2 microspheres greatly enhanced bone healing, whereas nonloaded PLGA microspheres in the CMC implants had little effect. The results showed that a lyophilized device of rhBMP-2/PLGA microspheres in CMC was an effective implantable protein-delivery system for use in bone repair.

Impact of carboxymethyl cellulose (CMC) and microcrystalline cellulose (MCC) on functional characteristics of emulsified sausages.

PubMed

Schuh, Valerie; Allard, Karin; Herrmann, Kurt; Gibis, Monika; Kohlus, Reinhard; Weiss, Jochen

2013-02-01

Inclusion of fibers, such as carboxymethyl cellulose (CMC) and microcrystalline cellulose (MCC), at the expense of fat or protein in meat batters could be used to produce healthier sausages while lowering production costs. To study the impact of CMC/MCC on structural/functional characteristics of emulsified sausages, standard-fat Lyoner-style sausages were formulated with CMC/MCC at concentrations of 0.3-2.0%. Methods of analysis included rheology, water binding capacity (WBC), texture measurements, and Confocal Laser Scanning Microscopy (CLSM). WBC, texture measurements, and rheology all indicated that addition of CMC (>0.7%) led to destabilization of the batter, which upon heating could no longer be converted into a coherent protein network, a fact that was also revealed in CLSM images. In contrast, MCC was highly compatible with the matrix and improved firmness (1405-1651N/100g) with increasing concentration compared to control (1381N/100g) while keeping WBC (4.6-5.9%) with <2% MCC at the level of the control (4.8%). Results were discussed in terms of molecular interactions of meat proteins with celluloses. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of CMC and arabic gum in the manufacture of jackfruit velva (Artocarpus heterophyllus)

NASA Astrophysics Data System (ADS)

Yudhistira, B.; Riyadi, N. H.; Pangestika, A. D.; Pertiwi, S. R.

2018-03-01

Velva is one type of frozen dessert which is made from fruit/vegetable with ice cream maker, low fat and high fiber content. Jackfruit is a raw material for the manufacture of velva because of the high fiber content of 2.31 gr. The use of a stabilizers combination of CMC and arabic gum in the manufacture of velva will provide a better gel mix than single use. The purpose of this research is to know the influence of variation of CMC and arabic gum stabilizer on the characteristics (physical, chemical, and sensory) of jackfruit velva (Artocarpus heterophyllus) and determine variations in the most appropriate combinations of stabilizers to produce jackfruit velva with the best quality. This research applied Completely Randomized Design consist of one factor which is the combination of CMC and arabic gum levels in the making of jackfruit velva with two replicates and two replications of the analysis. The data obtained then analyzed statistically using one way analysis of variance (ANOVA), when there is a significant difference, then followed by Duncan’s Multiple Range Test (DMRT) at significance level of 0.05. The results of this study concluded that the jackfruit velva with the addition of various concentrations of CMC and arabic gum is significantly affecting the taste, texture and overall parameters, but no significant difference on the color and flavor parameters of jackfruit velva. Based on the results of physical characteristics, chemical and sensory jackfruit velva with the addition of a stabilizing concentration of CMC and arabic gum 1: 1 result in best jackfruit velva. The best jackfruit velva with stabilizing the concentration of CMC and arabic gum 1: 1 contains a water content of 61.95%, dietary fiber 2.231%, total dissolved solids 20.38 °Brix, overrun 19.709%, meltdown 28.215 minutes. As for the color attribute score 3.72; Taste 4; flavor 3.60; Texture 3.68, and overall 3.88.

An Improved Algorithm of Congruent Matching Cells (CMC) Method for Firearm Evidence Identifications.

PubMed

Tong, Mingsi; Song, John; Chu, Wei

2015-01-01

The Congruent Matching Cells (CMC) method was invented at the National Institute of Standards and Technology (NIST) for firearm evidence identifications. The CMC method divides the measured image of a surface area, such as a breech face impression from a fired cartridge case, into small correlation cells and uses four identification parameters to identify correlated cell pairs originating from the same firearm. The CMC method was validated by identification tests using both 3D topography images and optical images captured from breech face impressions of 40 cartridge cases fired from a pistol with 10 consecutively manufactured slides. In this paper, we discuss the processing of the cell correlations and propose an improved algorithm of the CMC method which takes advantage of the cell correlations at a common initial phase angle and combines the forward and backward correlations to improve the identification capability. The improved algorithm is tested by 780 pairwise correlations using the same optical images and 3D topography images as the initial validation.

An Improved Algorithm of Congruent Matching Cells (CMC) Method for Firearm Evidence Identifications

PubMed Central

Tong, Mingsi; Song, John; Chu, Wei

2015-01-01

The Congruent Matching Cells (CMC) method was invented at the National Institute of Standards and Technology (NIST) for firearm evidence identifications. The CMC method divides the measured image of a surface area, such as a breech face impression from a fired cartridge case, into small correlation cells and uses four identification parameters to identify correlated cell pairs originating from the same firearm. The CMC method was validated by identification tests using both 3D topography images and optical images captured from breech face impressions of 40 cartridge cases fired from a pistol with 10 consecutively manufactured slides. In this paper, we discuss the processing of the cell correlations and propose an improved algorithm of the CMC method which takes advantage of the cell correlations at a common initial phase angle and combines the forward and backward correlations to improve the identification capability. The improved algorithm is tested by 780 pairwise correlations using the same optical images and 3D topography images as the initial validation. PMID:26958441

Form-focused Communicative Practice via CMC: What Language Learners Say

ERIC Educational Resources Information Center

Meskill, Carla; Anthony, Natasha

2007-01-01

Computer-mediated communication (CMC) is being used widely to support and extend foreign language instruction. Language learners are practicing the target language by communicating with their instructors, peers, and native speakers at a distance. This study examines high-beginning and low-intermediate learners of Russian and their uses of, and…

Radiographic Analysis of Simulated First Dorsal Interosseous and Opponens Pollicis Loading Upon Thumb CMC Joint Subluxation: A Cadaver Study.

PubMed

Adams, Julie E; O'Brien, Virginia; Magnusson, Erik; Rosenstein, Benjamin; Nuckley, David J

2018-01-01

Therapy programs to treat thumb carpometacarpal (CMC) arthritis may engage selective activation and reeducation of thenar muscles, particularly the first dorsal interosseous (FDI) and opponens pollicis (OP) to reduce subluxation of the joint. We describe the effect of simulated selective activation of the FDI and OP muscles upon radiographic subluxation of the thumb CMC joint. In a cadaver model of CMC subluxation, loads were applied to the FDI, the OP, and then concomitantly at 0%, 25%, 50%, 75%, and 100% maximal loads and radial subluxation of the joint and reduction in subluxation was measured. Selective activation of the OP, alone, improved the subluxation ratio (SR) in a dose-dependent manner. Selective activation of FDI, alone, demonstrated minimal effects on SR. Concomitant activation of OP and FDI improved the SR across all loading states, and activation of 75% and greater, when compared with FDI activation alone, resulted in a statistically significant improvement in SR to within 10% of the presubluxed joint. Concomitant activation of the FDI and OP acts to reduce subluxation of the thumb CMC joint in a dose-dependent fashion. The OP is likely the predominant reducing force. Hand therapy programs that focus on selective strengthening programs likely function in part to encourage patients to activate the easily palpable and easily understood FDI. Concomitant coactivation of the OP may be the major reducing force to elicit clinical and radiographic reduction of subluxation, improved thumb positioning, and reduction of pain and arthritic symptoms.

A Multi-Perspective Investigation into Learners' Interaction in Asynchronous Computer-Mediated Communication (CMC)

ERIC Educational Resources Information Center

Çardak, Çigdem Suzan

2016-01-01

This article focusses on graduate level students' interactions during asynchronous CMC activities of an online course about the teaching profession in Turkey. The instructor of the course designed and facilitated a semester-long asynchronous CMC on forum discussions, and investigated the interaction of learners in multiple perspectives: learners'…

CMC Research at NASA Glenn in 2015: Recent Progress and Plans

NASA Technical Reports Server (NTRS)

Grady, Joseph E.

2015-01-01

As part of NASAs Aeronautical Sciences project, Glenn Research Center has developed advanced fiber and matrix constituents for a 2700F CMC for turbine engine applications. Fiber and matrix development and characterization will be reviewed. Resulting improvements in CMC mechanical properties and durability will be summarized. Plans for 2015 will be described, including development and validation of models predicting effects of the engine environment on durability of SiC/SiC composites with Environmental Barrier Coatings

CMC prediction for ionic surfactants in pure water and aqueous salt solutions based solely on tabulated molecular parameters.

PubMed

Karakashev, Stoyan I; Smoukov, Stoyan K

2017-09-01

The critical micelle concentration (CMC) of various surfactants is difficult to predict accurately, yet often necessary to do in both industry and science. Hence, quantum-chemical software packages for precise calculation of CMC were developed, but they are expensive and time consuming. We show here an easy method for calculating CMC with a reasonable accuracy. Firstly, CMC 0 (intrinsic CMC, absent added salt) was coupled with quantitative structure - property relationship (QSPR) with defined by us parameter "CMC predictor" f 1 . It can be easily calculated from a number of tabulated molecular parameters - the adsorption energy of surfactant's head, the adsorption energy of its methylene groups, its number of carbon atoms, the specific adsorption energy of its counter-ions, their valency and bare radius. We applied this method to determine CMC 0 to a test set of 11 ionic surfactants, yielding 7.5% accuracy. Furthermore, we calculated CMC in the presence of added salts using the advanced version of Corrin-Harkins equation, which accounts for both the intrinsic and the added counter-ions. Our salt-saturation multiplier, accounts for both the type and concentration of the added counter-ions. We applied our theory to a test set containing 11 anionic/cationic surfactant+salt systems, achieving 8% accuracy. Copyright © 2017 Elsevier Inc. All rights reserved.

Strategic Use of Modality during Synchronous CMC

ERIC Educational Resources Information Center

Sauro, Shannon

2009-01-01

Research on computer-mediated communication (CMC) in the second language (L2) classroom has revealed the potential for technology to promote learner interaction and opportunities for negotiation of meaning as well as to provide opportunities for language access outside the classroom environment. Despite this potential, social, linguistic, and…

CMC Research at NASA Glenn in 2016: Recent Progress and Plans

NASA Technical Reports Server (NTRS)

Grady, Joseph E.

2016-01-01

As part of NASA's Aeronautical Sciences project, Glenn Research Center has developed advanced fiber and matrix constituents for a 2700 degrees Fahrenheit CMC (Ceramic Matrix Composite) for turbine engine applications. Fiber and matrix development and characterization will be reviewed. Resulting improvements in CMC mechanical properties and durability will be summarized. Plans for 2015 will be described, including development and validation of models predicting effects of the engine environment on durability of SiCSiC composites with Environmental Barrier Coatings (EBCs).

Initial experience with CMC-544 (inotuzumab ozogamicin) in pediatric patients with relapsed B-cell acute lymphoblastic leukemia.

PubMed

Rytting, Michael; Triche, Lisa; Thomas, Deborah; O'Brien, Susan; Kantarjian, Hagop

2014-02-01

Survival is poor in pediatric patients with relapsed or refractory acute B-cell lymphoblastic leukemia (ALL) and therapeutic options are limited. CMC-544 (inotuzumab ozogamicin) has shown significant activity in adult patients with relapsed and refractory ALL. We evaluated CMC-544 in pediatric patients with multiply relapsed ALL. Five children 4-15 years old with relapsed, CD 22 positive B-cell ALL were enrolled on a phase II non-randomized trial of CMC-544. CMC-544 was initially administered at 1.3 mg/m(2) every 3 weeks. The dose then increased to 1.8 mg/m(2) every 3 weeks. Subsequently, a weekly schedule of CMC-544 given as 0.8 mg/m(2) on day 1 followed by 0.5 mg/m(2) on days 8 and 15 was administered. All five patients had refractory relapsed B-cell ALL. Lymphoblasts for all patients highly expressed CD22. Four patients had two or more relapses before starting the study drug. One patient achieved a complete remission in the bone marrow and normal peripheral counts, and two patients achieved bone marrow morphologic remission with absolute neutrophils >1,000/µl but platelets <100,000/µl. Two patients had no response to the drug. Toxicities consisted of fever, sepsis, and liver enzyme elevation. Single agent CMC-544 given at the single dose of 1.8 mg/m(2) every 3 weeks or given as a split, weekly dose was generally well tolerated considering the inherent risks in this population of patients and showed promising activity in pediatric patients with relapsed and refractory ALL. © 2013 Wiley Periodicals, Inc.

The Adsorption Capacity of GONs/CMC/Fe₃O₄ Magnetic Composite Microspheres and Applications for Purifying Dye Wastewater.

PubMed

Lv, Shenghua; Zhu, Linlin; Li, Ying; Jia, Chunmao; Sun, Shiyu

2017-01-11

Graphene oxide nanosheets (GONs)/carboxymethyl chitosan (CMC)/Fe₃O₄ magnetic composite microspheres (MCMs) were prepared by enclosing Fe₃O₄ particles with CMC and GONs in turn. The microstructures of GONs and GONs/CMC/Fe₃O₄ MCMs were characterized by FTIR, XRD, TEM, and SEM. The effects of GON content, pH value, and adsorption time on the adsorption capacity of the MCMs were investigated. The results show that the GONs/CMC/Fe₃O₄ MCMs have a greater specific surface area and a strong adsorption capacity for dye wastewater. Meanwhile, the adsorption mechanism was investigated, and the results accorded with the pseudo-second-order kinetic model and the Freundlich isotherm model. The search results indicate that GONs/CMC/Fe₃O₄ MCMs can be used to purify dye wastewater and has an important potential use in the practical purification of dye wastewater.

The Effects of CMC Applications on ESL Writing Anxiety among Postgraduate Students

ERIC Educational Resources Information Center

Hussin, Supyan; Abdullah, Mohamad Yahya; Ismail, Noriah; Yoke, Soo Kum

2015-01-01

This study investigates the effects of the CMC applications on the ESL/EFL writing anxiety. This is a descriptive study using a mixed-method that adopted both quantitative and qualitative approaches. Three instruments were employed to answer the research questions of the current study which are Second Language Writing Anxiety Inventory (SLWAI),…

Rheological Characterization of Polyoxyethylene (POE) and Carboxymethyl Cellulose (CMC) Suspensions with Added Solids

NASA Astrophysics Data System (ADS)

Mora, A.; Skurtys, O.; Osorio, F.

2015-04-01

The rheological properties of high molecular weight POE and CMC suspensions by adding micro-metric solid particles such as fibers or spheres were studied. The volume fraction, Φ, was varied between 0 and 0.4. Their rheological properties were obtained after fitting a Cross model. For POE suspending fluid with spherical particle, the behavior of the normalized steady shear viscosity, μ/μ0, as function of the fraction volume followed a Thomas model. However, for CMC suspensions, μ/μ0 seems to be lineal with Φ. For a pure fluid or a suspension with Φ = 0; 2, the suspension presented an elastic behavior whereas it was observed a viscous behavior when the volume fraction was increased.

Psychological underpinnings of intrafamilial computer-mediated communication: a preliminary exploration of CMC uptake with parents and siblings.

PubMed

Goby, Valerie Priscilla

2011-06-01

This preliminary study investigates the uptake of computer-mediated communication (CMC) with parents and siblings, an area on which no research appears to have been conducted. Given the lack of relevant literature, grounded theory methodology was used and online focus group discussions were conducted in an attempt to generate suitable hypotheses for further empirical studies. Codification of the discussion data revealed various categories of meaning, namely: a perceived inappropriateness of CMC with members of family of origin; issues relating to the family generational gap; the nature of the offline sibling/parent relationship; the non-viability of online affordances such as planned self-disclosure, deception, identity construction; and disinhibition in interactions with family-of-origin members. These themes could be molded into hypotheses to assess the psychosocial limitations of CMC and to determine if it can indeed become a ubiquitous alternative to traditional communication modes as some scholars have claimed.

Synergistic effects of guanidine-grafted CMC on enhancing antimicrobial activity and dry strength of paper.

PubMed

Liu, Kai; Xu, Yaoguang; Lin, Xinxing; Chen, Lihui; Huang, Liulian; Cao, Shilin; Li, Jian

2014-09-22

In order to improve the strength property and antimicrobial activity of paper simultaneously, we prepared a novel multifunctional agent based on carboxymethyl cellulose (CMC) by a simple two-stage method. The first stage was the oxidation of CMC to obtain the dialdehyde CMC (DCMC), and the second stage was the graft of guanidine hydrochloride (GH) onto DCMC to obtain DCMC-GH polymer. The strength property and antimicrobial activity of DCMC-GH-coated copy paper have been studied by the tensile test and inhibition zone method, respectively. The results showed that the dry strength index could increase about 20% after the paper was coated with DCMC-GH. The coating of DCMC-GH on paper also resulted in excellent antimicrobial activities against Escherichia coli and Staphylococcus aureus, and the inhibition zone became larger as the GH content grafted on DCMC increased. The novel DCMC-GH polymer would be a multifunctional coating agent for food packaging paper. Copyright © 2014 Elsevier Ltd. All rights reserved.

It's Just a Game, Right? Types of Play in Foreign Language CMC

ERIC Educational Resources Information Center

Warner, Chantelle N.

2004-01-01

This study focuses on the various playful uses of language that occurred during a semester-long study of two German language courses using one type of synchronous network-based medium, the MOO. Research and use of synchronous computer-mediated communication (CMC) have flourished in the study of second-language acquisition (SLA) since the late…

The influence of carboxymethylcellulose (CMC) on the reactivity of Fe NPs toward decabrominated diphenyl ether: The Ni doping, temperature, pH, and anion effects.

PubMed

Tso, Chih-Ping; Shih, Yang-Hsin

2017-01-15

Polybrominated diphenyl ethers (PBDEs) are commonly used brominated flame retardants in many products. They have accumulated in the environment and become widely dispersed. In this study, carboxymethylcellulose (CMC) was applied to modify nanoscale zerovalent iron (NZVI) and bimetallic Ni/Fe nanoparticles (NPs) to prevent NP aggregation. In this study the removal kinetics of the decabrominated diphenyl ethers (DBDE) with CMC-stabilized Fe NPs were evaluated. CMC-stabilized Ni/Fe NPs with an average size of 86.7nm contained metallic Fe 0 and reduced Ni. The colloidal stability decreased with a decrease in pH, which was further accompanied by a change in the removal rate of DBDE. Our results showed that anions do not change the removal rates of DBDE, with the exception of 10mM NO 3 - , which induced the formation of Fe (hydro)oxides on the Fe NP surface, which could further coagulate with DBDE. This study provides important information for our understanding of the influence of CMC coatings on the reactivity of Fe NPs. Because CMC coatings prevent the passivation of Fe in the presence of anions, CMC-coated Fe NPs show potential for the in-situ remediation of PBDEs in the environment. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of CMC addition on steady and dynamic shear rheological properties of binary systems of xanthan gum and guar gum.

PubMed

Bak, J H; Yoo, B

2018-04-12

The effect of CMC on the steady and dynamic shear rheological properties of binary mixtures of XG and GG was examined at different mixing ratios. All XG-GG-CMC ternary mixtures had high shear-thinning behavior and the n value of the sample with 5% CMC was the smallest compared with those of other samples. A marked increase in K and η a,50 values was observed for ternary mixtures at a lower content (5%) of CMC, indicating that the synergistic interactions of the XG-GG binary mixture were affected by the content of CMC. The effect of temperature on the η a,50 was well described by the Arrhenius equation for all samples. The activation energy values of all ternary gum mixtures are higher than that of binary gum mixture, and these values also decreased with an increase in CMC content from 5 to 15%. The dynamic moduli of ternary gum mixtures decreased with an increase in CMC content. The tan δ value of the ternary gum mixture with 5% CMC was much lower than those of other ternary mixtures. In general, these results suggest that the flow and dynamic shear rheological properties of XG-GG binary mixtures are strongly influenced by a small addition of CMC. Copyright © 2018. Published by Elsevier B.V.

Simultaneous adsorption of Cu2+ and Acid fuchsin (AF) from aqueous solutions by CMC/bentonite composite.

PubMed

Gong, Ning; Liu, Yanping; Huang, Ruihua

2018-04-21

Carboxymethyl-chitosan (CMC)/bentonite composite was prepared by the method of membrane-forming, and characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques. The simultaneous adsorption of Cu 2+ and Acid fuchsin (AF) applying CMC/bentonite composite as an adsorbent in single or binary systems was investigated. The adsorption study was conducted systematically by varying the ratio of CMC to bentonite, adsorbent dosage, initial pH value, initial Cu 2+ (or AF) concentration, contact time and the interaction of two components in binary solutions. The results showed that the presence of Cu 2+ hindered the adsorption of AF, while the presence of AF almost had no influence on the adsorption of Cu 2+ in binary systems. The adsorption data of Cu 2+ and AF were both suitable for Langmuir isotherm model, and the maximum adsorption capacities of CMC/bentonite composite, according to the Langmuir isotherm model were 81.4 mg/g for Cu 2+ and 253.2 mg/g for AF at 298 K. The pseudo-second-order model could better describe the adsorption process of Cu 2+ and AF. Thermodynamic constant values illustrated that the adsorption of Cu 2+ was endothermic, while the adsorption process of AF was exothermic. Copyright © 2018. Published by Elsevier B.V.

Verification of RRA and CMC in OpenSim

NASA Astrophysics Data System (ADS)

Ieshiro, Yuma; Itoh, Toshiaki

2013-10-01

OpenSim is the free software that can handle various analysis and simulation of skeletal muscle dynamics with PC. This study treated RRA and CMC tools in OpenSim. It is remarkable that we can simulate human motion with respect to nerve signal of muscles using these tools. However, these tools seem to still in developmental stages. In order to verify applicability of these tools, we analyze bending and stretching motion data which are obtained from motion capture device using these tools. In this study, we checked the consistency between real muscle behavior and numerical results from these tools.

Catalytic hydrodechlorination of trichloroethylene in water with supported CMC-stabilized palladium nanoparticles.

PubMed

Zhang, Man; Bacik, Deborah B; Roberts, Christopher B; Zhao, Dongye

2013-07-01

In this work, we developed and tested a new class of supported Pd catalysts by immobilizing CMC (carboxymethyl cellulose) stabilized Pd nanoparticles onto alumina support. The alumina supported Pd nanoparticles were able to facilitate rapid and complete hydrodechlorination of TCE (trichloroethylene) without intermediate by-products detected. With a Pd mass loading of 0.33 wt% of the alumina mass, the observed pseudo first order reaction rate constant, k(obs), for the catalyst was increased from 28 to 109 L/min/g when CMC concentration was raised from 0.005 to 0.15 wt%. The activity increase was in accord with an increase of the Pd dispersion (measured via CO chemisorption) from 30.4% to 45.1%. Compared to the commercial alumina supported Pd, which has a lower Pd dispersion of 21%, our CMC-stabilized Pd nanoparticles offered more than 7 times greater activity. Pre-calcination treatment of the supported catalyst resulted in minor drop in activity, yet greatly reduced bleeding (<6%) of the Pd nanoparticles from the support during multiple cycles of applications. The presence of DOM (dissolved organic matter) at up to 10 mg/L as TOC had negligible effect on the catalytic activity. The alumina supported CMC-stabilized Pd nanoparticles may serve as a class of more effective catalysts for water treatment uses. Copyright © 2013 Elsevier Ltd. All rights reserved.

Facile preparation and characterization of pH sensitive Mt/CMC nanocomposite hydrogel beads for propranolol controlled release.

PubMed

Farhadnejad, Hassan; Mortazavi, Seyed Alireza; Erfan, Mohammad; Darbasizadeh, Behzad; Motasadizadeh, Hamidreza; Fatahi, Yousef

2018-05-01

The main aim of the present study was to design pH-sensitive nanocomposite hydrogel beads, based on carboxymethyl cellulose (CMC) and montmorillonite (Mt)-propranolol (PPN) nanohybrid, and evaluate whether the prepared nanocomposite beads could potentially be used as oral drug delivery systems. PPN-as a model drug-was intercalated into the interlayer space of Mt clay mineral via the ion exchange procedure. The resultant nanohybrid (Mt-PPN) was applied to fabricate nanocomposite hydrogel beads by association with carboxymethyl cellulose. The characterization of test samples was performed using different techniques: X-Ray Diffraction (XRD), IR spectroscopy (FT-IR), thermal gravity analysis (TGA), and scanning electron microscopy (SEM). The drug encapsulation efficiency was evaluated by UV-vis spectroscopy, and was found to be high for Mt/CMC beads. In vitro drug release test was performed in the simulated gastrointestinal conditions to evaluate the efficiency of Mt-PPN/CMC nanocomposite beads as a controlled-release drug carrier. The drug release profiles indicated that the Mt-PPN/CMC nanocomposite beads had high stability against stomach acid and a sustained- and controlled-release profile for PPN under the simulated intestinal conditions. Copyright © 2018 Elsevier B.V. All rights reserved.

Overview of CMC (Ceramic Matrix Composite) Research at the NASA Glenn Research Center

NASA Technical Reports Server (NTRS)

Kiser, J. Douglas; Grady, Joseph E.; Bhatt, Ramakrishna T.; Wiesner, Valerie L.; Zhu, Dongming

2016-01-01

In support of NASAs Aeronautics Research Mission, the Glenn Research Center has developed and assessed various constituents for a high temperature (2700F) SiCSiC CMC system for turbine engine applications. Combinations of highly creep-resistant SiC fibers, advanced 3D weaves, durable environmental barrier coatings (EBCs), and a 2700F-capable hybrid SiC matrix are being developed evaluated. The resulting improvements in CMC mechanical properties and durability will be summarized. The development and validation of models for predicting the effects of the environment on the durability of CMCs and EBCs and other operating-environment challenges including the effect of CMAS (calcium magnesium aluminosilicate) degradation of EBCs will be discussed. Progress toward the development of CMC joining technology for 2400F joint applications will also be reviewed.

Comparison of the effects of Mitomycin-C and sodium hyaluronate/carboxymethylcellulose [NH/CMC] (Seprafilm) on abdominal adhesions.

PubMed

Ozerhan, Ismail Hakkı; Urkan, Murat; Meral, Ulvi Mehmet; Unlu, Aytekin; Ersöz, Nail; Demirag, Funda; Yagci, Gokhan

2016-01-01

Intra-abdominal adhesions (IA) may occur after abdominal surgery and also may lead to complications such as infertility, intestinal obstruction and chronic pain. The aim of this study was to compare the effects of Mitomycin-C (MM-C) and sodium hyaluronate/carboxymethylcellulose [NH/CMC] on abdominal adhesions in a cecal abrasion model and to investigate the toxicity of MM-C on complete blood count (CBC) and bone marrow analyses. The study comprised forty rats in four groups (Control, Sham, Cecal abrasion + MM-C, and Cecal abrasion + NH/CMC). On postoperative day 21, all rats except for the control (CBC + femur resection) group, were sacrificed. Macroscopical and histopathological evaluations of abdominal adhesions were performed. In order to elucidate the side effects of MM-C; CBC analyses and femur resections were performed to examine bone marrow cellularity. CBC analyses and bone marrow cellularity assessment revealed no statistically significant differences between MM-C, NH/CMC and control groups. No significant differences in inflammation scores were observed between the groups. The MM-C group had significantly lower fibrosis scores compared to the NH/CMC and sham groups. Although the adhesion scores were lower in the MM-C group, the differences were not statistically significant. Despite its potential for systemic toxicity, MM-C may show some anti-fibrosis and anti-adhesive effects. MM-C is a promising agent for the prevention of IAs, and as such, further trials are warranted to study efficacy.

Effect of polysaccharide admixtures on expression of multiple polysaccharide-degrading enzymes in Microbulbifer strain CMC-5.

PubMed

Jonnadula, RaviChand; Imran, Md; Poduval, Preethi B; Ghadi, Sanjeev C

2018-03-01

Microbulbifer strain CMC-5 produces agarase, alginate lyase, xylanase, carboxymethyl cellulase and carrageenase. The extracellular production of the above carbohydrases was investigated by growing Microbulbifer strain CMC-5 in a sea water based medium containing homologous/heterologous polysaccharides as a single substrate or as a combination of mixed assorted substrate. Presence of singular homologous polysaccharides in the growth medium induces respective carbohydrase at high levels. Any two polysaccharides in various combinations produced high level of homologous carbohydrase and low level of other heterologous carbohydrase. All five carbohydrases were consistently produced by strain CMC-5, when carboxymethyl cellulose was included as one of the substrate in dual substrate combination, or in presence of mix blends of all five polysaccharides. Interestingly, thalli of Gracilaria sp. that contain agar and cellulose predominantly in their cell wall induces only agarase expression in strain CMC-5.

The Computer-Mediated Communication (CMC) Classroom: A Challenge of Medium, Presence, Interaction, Identity, and Relationship

ERIC Educational Resources Information Center

Sherblom, John C.

2010-01-01

There is a "prevalence of computer-mediated communication (CMC) in education," and a concern for its negative psychosocial consequences and lack of effectiveness as an instructional tool. This essay identifies five variables in the CMC research literature and shows their moderating effect on the psychosocial, instructional expevrience of the CMC…

Presentation on the Modeling and Educational Demonstrations Laboratory Curriculum Materials Center (MEDL-CMC): A Working Model and Progress Report

NASA Astrophysics Data System (ADS)

Glesener, G. B.; Vican, L.

2015-12-01

Physical analog models and demonstrations can be effective educational tools for helping instructors teach abstract concepts in the Earth, planetary, and space sciences. Reducing the learning challenges for students using physical analog models and demonstrations, however, can often increase instructors' workload and budget because the cost and time needed to produce and maintain such curriculum materials is substantial. First, this presentation describes a working model for the Modeling and Educational Demonstrations Laboratory Curriculum Materials Center (MEDL-CMC) to support instructors' use of physical analog models and demonstrations in the science classroom. The working model is based on a combination of instructional resource models developed by the Association of College & Research Libraries and by the Physics Instructional Resource Association. The MEDL-CMC aims to make the curriculum materials available for all science courses and outreach programs within the institution where the MEDL-CMC resides. The sustainability and value of the MEDL-CMC comes from its ability to provide and maintain a variety of physical analog models and demonstrations in a wide range of science disciplines. Second, the presentation then reports on the development, progress, and future of the MEDL-CMC at the University of California Los Angeles (UCLA). Development of the UCLA MEDL-CMC was funded by a grant from UCLA's Office of Instructional Development and is supported by the Department of Earth, Planetary, and Space Sciences. Other UCLA science departments have recently shown interest in the UCLA MEDL-CMC services, and therefore, preparations are currently underway to increase our capacity for providing interdepartmental service. The presentation concludes with recommendations and suggestions for other institutions that wish to start their own MEDL-CMC in order to increase educational effectiveness and decrease instructor workload. We welcome an interuniversity collaboration to

Biotech outsourcing strategies cmc--biologics stream. June 17, 2010, Copenhagen, Denmark.

PubMed

Hamer, Kate

2010-01-01

Now in its third year, the Biotech Outsourcing Strategies (BOS) meeting organized by Bio2Business took place at the Søhuset Conference Centre in Hørsholm, Copenhagen. The focus of this year's event was the demanding and challenging area of chemistry, manufacturing and controls (CMC), and the meeting provided ample opportunity for lively discussion of the key issues surrounding this area. New for the 2010 conference, a biologics-focused lecture stream ran in parallel to the established small molecule stream. Both streams boasted a distinguished panel of keynote speakers who discussed all aspects of CMC from early stage scale-up through late stage clinical development. In addition to the keynote speakers, selected contract research organizations (CROs) gave short presentations on the solutions that they could provide to some of the challenges facing CMC. The meeting attracted more than 150 delegates from leading drug development companies and CRO service providers, and greatly facilitated the forging of new working relationships through pre-arranged one-to-one meetings. Moreover, exhibitions from event sponsors and considerable scheduled networking time over lunch and evening reception further enhanced the highly productive and interactive nature of the meeting.

The use of sodium hyaluronate-carboxymethylcellulose (HA-CMC) barrier in gynecologic malignancies: a retrospective review of outcomes.

PubMed

Tan, Annie; Argenta, Peter; Ramirez, Rose; Bliss, Robin; Geller, Melissa

2009-02-01

Concerns exist regarding the safety of sodium hyaluronate-carboxymethylcellulose (HA-CMC, Seprafilm) adhesion barrier in regard to cancer survival as a result of in vitro data demonstrating that hyaluronan, a component of HA-CMC, may promote tumor growth. We sought to determine whether use of HA-CMC is associated with duration of disease-free or overall survival and rates of immediate complication in patients with gynecologic malignancies. We identified 202 consecutive patients with epithelial ovarian, fallopian tube, and primary peritoneal cancer who underwent initial surgical staging or interval debulking at the University of Minnesota between January 2001 and December 2004. Information on patients' demographics, medical history, surgical procedures, postoperative complications, disease stage, histology, adjuvant therapy, and disease-free and overall survival was collected from medical records. Survival curves were compared between patients receiving or not receiving HA-CMC by stratified Cox regression models, log rank, and Wilcoxon tests. The level of significance was set to alpha = .05 for each test. Eighty patients received intraoperative placement of HA-CMC and 122 did not. Immediate postoperative complication rates were equivalent in both groups. Median follow-up was 2.1 years. There was no difference in disease-free survival (5-year estimate 23.6% vs. 33.3%, P = .80) or overall survival (5-year estimate 29.7% vs. 40.3%, P = .75) between those who received HA-CMC and those who did not. Our retrospective analysis suggests that HA-CMC adhesion barrier does not affect disease-free survival or overall survival; nor does it increase the immediate postoperative complication rates in patients undergoing abdominal surgery for ovarian, fallopian tube, and primary peritoneal carcinomas.

Biomimetic remineralization of demineralized dentine using scaffold of CMC/ACP nanocomplexes in an in vitro tooth model of deep caries.

PubMed

Chen, Zhen; Cao, Shansong; Wang, Haorong; Li, Yanqiu; Kishen, Anil; Deng, Xuliang; Yang, Xiaoping; Wang, Yinghui; Cong, Changhong; Wang, Huajun; Zhang, Xu

2015-01-01

Currently, it is still a tough task for dentists to remineralize dentine in deep caries. The aim of this study was to remineralize demineralized dentine in a tooth model of deep caries using nanocomplexes of carboxymethyl chitosan/amorphous calcium phosphate (CMC/ACP) based on mimicking the stabilizing effect of dentine matrix protein 1 (DMP1) on ACP in the biomineralization of dentine. The experimental results indicate that CMC can stabilize ACP to form nanocomplexes of CMC/ACP, which is able to be processed into scaffolds by lyophilization. In the single-layer collagen model, ACP nanoparticles are released from scaffolds of CMC/ACP nanocomplexes dissolved and then infiltrate into collagen fibrils via the gap zones (40 nm) to accomplish intrafibrillar mineralization of collagen. With this method, the completely demineralized dentine was partially remineralized in the tooth mode. This is a bottom-up remineralizing strategy based on non-classical crystallization theory. Since nanocomplexes of CMC/ACP show a promising effect of remineralization on demineralized dentine via biomimetic strategy, thereby preserving dentinal tissue to the maximum extent possible, it would be a potential indirect pulp capping (IPC) material for the management of deep caries during vital pulp therapy based on the concept of minimally invasive dentistry (MID).

Biomimetic Remineralization of Demineralized Dentine Using Scaffold of CMC/ACP Nanocomplexes in an In Vitro Tooth Model of Deep Caries

PubMed Central

Chen, Zhen; Cao, Shansong; Wang, Haorong; Li, Yanqiu; Kishen, Anil; Deng, Xuliang; Yang, Xiaoping; Wang, Yinghui; Cong, Changhong; Wang, Huajun; Zhang, Xu

2015-01-01

Currently, it is still a tough task for dentists to remineralize dentine in deep caries. The aim of this study was to remineralize demineralized dentine in a tooth model of deep caries using nanocomplexes of carboxymethyl chitosan/amorphous calcium phosphate (CMC/ACP) based on mimicking the stabilizing effect of dentine matrix protein 1 (DMP1) on ACP in the biomineralization of dentine. The experimental results indicate that CMC can stabilize ACP to form nanocomplexes of CMC/ACP, which is able to be processed into scaffolds by lyophilization. In the single-layer collagen model, ACP nanoparticles are released from scaffolds of CMC/ACP nanocomplexes dissolved and then infiltrate into collagen fibrils via the gap zones (40 nm) to accomplish intrafibrillar mineralization of collagen. With this method, the completely demineralized dentine was partially remineralized in the tooth mode. This is a bottom-up remineralizing strategy based on non-classical crystallization theory. Since nanocomplexes of CMC/ACP show a promising effect of remineralization on demineralized dentine via biomimetic strategy, thereby preserving dentinal tissue to the maximum extent possible, it would be a potential indirect pulp capping (IPC) material for the management of deep caries during vital pulp therapy based on the concept of minimally invasive dentistry (MID). PMID:25587986

CMC Property Variability and Life Prediction Methods for Turbine Engine Component Application

NASA Technical Reports Server (NTRS)

Cheplak, Matthew L.

2004-01-01

The ever increasing need for lower density and higher temperature-capable materials for aircraft engines has led to the development of Ceramic Matrix Composites (CMCs). Today's aircraft engines operate with >3000"F gas temperatures at the entrance to the turbine section, but unless heavily cooled, metallic components cannot operate above approx.2000 F. CMCs attempt to push component capability to nearly 2700 F with much less cooling, which can help improve engine efficiency and performance in terms of better fuel efficiency, higher thrust, and reduced emissions. The NASA Glenn Research Center has been researching the benefits of the SiC/SiC CMC for engine applications. A CMC is made up of a matrix material, fibers, and an interphase, which is a protective coating over the fibers. There are several methods or architectures in which the orientation of the fibers can be manipulated to achieve a particular material property objective as well as a particular component geometric shape and size. The required shape manipulation can be a limiting factor in the design and performance of the component if there is a lack of bending capability of the fiber as making the fiber more flexible typically sacrifices strength and other fiber properties. Various analysis codes are available (pcGINA, CEMCAN) that can predict the effective Young's Moduli, thermal conductivities, coefficients of thermal expansion (CTE), and various other properties of a CMC. There are also various analysis codes (NASAlife) that can be used to predict the life of CMCs under expected engine service conditions. The objective of this summer study is to utilize and optimize these codes for examining the tradeoffs between CMC properties and the complex fiber architectures that will be needed for several different component designs. For example, for the pcGINA code, there are six variations of architecture available. Depending on which architecture is analyzed, the user is able to specify the fiber tow size, tow

Non-CMC solutions to the Einstein constraint equations on asymptotically Euclidean manifolds with apparent horizon boundaries

NASA Astrophysics Data System (ADS)

Holst, Michael; Meier, Caleb

2015-01-01

In this article we further develop the solution theory for the Einstein constraint equations on an n-dimensional, asymptotically Euclidean manifold M with interior boundary Σ. Building on recent results for both the asymptotically Euclidean and compact with boundary settings, we show the existence of far-from-CMC and near-CMC solutions to the conformal formulation of the Einstein constraints when nonlinear Robin boundary conditions are imposed on Σ, similar to those analyzed previously by Dain (2004 Class. Quantum Grav. 21 555-73), by Maxwell (2004, 2005 Commun. Math. Phys. 253 561-83), and by Holst and Tsogtgerel (2013 Class. Quantum Grav. 30 205011) as a model of black holes in various CMC settings, and by Holst et al (2013 Non-CMC solutions to the einstein constraint equations with apparent horizon boundaries arXiv:1310.2302v1) in the setting of far-from-CMC solutions on compact manifolds with boundary. These ‘marginally trapped surface’ Robin conditions ensure that the expansion scalars along null geodesics perpendicular to the boundary region Σ are non-positive, which is considered the correct mathematical model for black holes in the context of the Einstein constraint equations. Assuming a suitable form of weak cosmic censorship, the results presented in this article guarantee the existence of initial data that will evolve into a space-time containing an arbitrary number of black holes. A particularly important feature of our results are the minimal restrictions we place on the mean curvature, giving both near- and far-from-CMC results that are new.

Oxide_Oxide Ceramic Matrix Composite (CMC) Exhaust Mixer Development in the NASA Environmentally Responsible Aviation (ERA) Project

NASA Technical Reports Server (NTRS)

Kiser, James D.; Bansal, Narottam P.; Szelagowski, J.; Sokhey, J.; Heffernan, T.; Clegg, J.; Pierluissi, A.; Riedell, J.; Atmur, S.; Wyen, T.;

Synthesis and characterization of tat-mediated O-CMC magnetic nanoparticles having anticancer function

NASA Astrophysics Data System (ADS)

Zhao, Aijie; Yao, Peng; Kang, Chunshang; Yuan, Xubo; Chang, Jin; Pu, Peiyu

2005-08-01

This paper describes a new formulation of magnetic nanoparticles coated by a novel polymer matrix—O-carboxylmethylated chitosan (O-CMC) as drug/gene carrier. The O-CMC magnetic nanoparticles were derivatized with a peptide sequence from the HIV-tat protein to improve the translocational property and cellar uptake of the nanoparticles. To evaluate the O-MNPs-tat as drug carriers, MTX was incorporated as a model drug and MTX-loaded O-MNPs-tat with an average diameter of 45-60 nm were prepared and characterized by TEM, AFM and VSM. The cytotoxicity of MTX-loaded O-MNPs-tat was investigated with U-937 tumor cells. The results showed that the MTX-loaded O-MNPs-tat retained significant antitumor toxicity; additionally, sustained release of MTX from O-CMC nanoparticles was observed in vitro, suggesting that the tat-O-MNPs could be a novel magnetic targeting carrier.

Language Learning Going Global: Linking Teachers and Learners via Commercial Skype-Based CMC

ERIC Educational Resources Information Center

Terhune, N. M.

2016-01-01

This paper reports on students' use of face-to-face synchronous computer-mediated communication (CMC) for oral language learning. It describes a university English language class designed to prepare students for overseas study in which a Skype-based English conversation school was piloted. The study offers analysis of how students used the CMC…

The Impact of Text-Based CMC on Improving L2 Oral Fluency

ERIC Educational Resources Information Center

Razagifard, P.

2013-01-01

This paper reports on a study investigating the potential effect of synchronous and asynchronous text-based computer-mediated communication (CMC) on oral fluency development of second-language (L2) learners. Sixty-three intermediate learners of English were randomly assigned to one of three groups (two experimental groups and one control group),…

Influence of xanthan, guar, CMC and gum acacia on functional properties of water chestnut (Trapa bispinosa) starch.

PubMed

Lutfi, Zubala; Nawab, Anjum; Alam, Feroz; Hasnain, Abid; Haider, Syed Zia

2017-10-01

This study was performed to determine the effect of xanthan, guar, CMC and gum acacia on functional and pasting properties of starch isolated from water chestnut (Trapa bispinosa). Morphological properties of water chestnut starch with CMC were studied by scanning electron microscopy (SEM). The addition of hydrocolloids significantly enhanced the solubility of water chestnut starch (WCS) while reduced swelling power and freeze-thaw stability. The hydrophilic tendency of WCS was increased by xanthan gum; however, with addition of gum acacia it decreased significantly. Starch was modified with guar and gum acacia exhibited highest% syneresis. Guar gum was found to be effective in increasing the clarity of water chestnut starch paste. The addition of CMC significantly reduced the pasting temperature of WCS indicating ease of gelatinization. The setback was accelerated in the presence of xanthan gum but gum acacia delayed this effect during the cooling of the starch paste. Only xanthan gum was found to be effective in increasing breakdown showing good paste stability of WCS. Copyright © 2017 Elsevier B.V. All rights reserved.

Perceptions of Talk, Text, Transactions, and Technology: Preservice Teachers, CMC, and Reader Response

ERIC Educational Resources Information Center

Akers, Anne Trice Thompson

2009-01-01

This qualitative study examined middle grades preservice language arts teachers' perceptions of young adult literature through the lenses of reader response, new literacy, and activity theory. Undergraduate preservice teachers used synchronous and asynchronous computer-mediated communication (CMC) to respond online to three young adult books with…

Viscoelastic behavior of mineralized (CaCO3) chitin based PVP-CMC hydrogel scaffolds

NASA Astrophysics Data System (ADS)

Čadež, Vida; Saha, Nabanita; Sikirić, Maja Dutour; Saha, Petr

2017-05-01

Enhancement of the mechanical as well as functional properties of the perspective mineralized PVP-CMC-CaCO3 hydrogel scaffold applicable for bone tissue engineering is quite essential. Therefore, the incorporation feasibility of chitin, a bioactive, antibacterial and biodegradable material, was examined in order to test its ability to enchance mechanical properties of the PVP-CMC-CaCO3 hydrogel scaffold. Chitin based PVP-CMC hydrogels were prepared and characterized both as non-mineralized and mineralized (CaCO3) form of hydrogel scaffolds. Both α-chitin (commercially bought) and β-chitin (isolated from the cuttlebone) were individually tested. It was observed that at 1% strain all hydrogel scaffolds have linear trend, with highly pronounced elastic properties in comparison to viscous ones. The complex viscosity has directly proportional behavior with negative slope against angular frequency within the range of ω = 0.1 - 100 rad.s-1. Incorporation of β-chitin increased storage modulus of all mineralized samples, making it interesting for further research.

Milestones Towards Hot CMC Structures for Operational Space Rentry Vehicles

NASA Astrophysics Data System (ADS)

Hald, H.; Weihs, H.; Reimer, T.

2002-01-01

Hot structures made of ceramic matrix composites (CMC) for space reentry vehicles play a key role regarding feasibility of advanced and reusable future space transportation systems. Thus realization of applicable flight hardware concerning hot primary structures like a nose cap or body flaps and thermal protection systems (TPS) requires system competence w.r.t. sophisticated know how in material processing, manufacturing and qualification of structural components and in all aspects from process control, use of NDI techniques, arc jet testing, hot structure testing to flight concept validation. This goal has been achieved so far by DLR while following a dedicated development road map since more than a decade culminating at present in the supply of the nose cap system for NASA's X-38; the flight hardware has been installed successfully in October 2001. A number of unique hardware development milestones had to be achieved in the past to finally reach this level of system competence. It is the intention of this paper to highlight the most important technical issues and achievements from the essential projects and developments to finally provide a comprehensive insight into DLR's past and future development road map w.r.t. CMC hot structures for space reentry vehicles. Based on DLR's C/C-SiC material which is produced with the inhouse developed liquid silicon infiltration process (LSI) the development strategy first concentrated on basic material properties evaluation in various arc jet testing facilities. As soon as a basic understanding of oxidation and erosion mechanisms had been achieved further efforts concentrated on inflight verification of both materials and design concepts for hot structures. Consequently coated and uncoated C/C-SiC specimens were integrated into the ablative heat shield of Russian FOTON capsules and they were tested during two missions in 1992 and 1994. Following on, a hot structure experiment called CETEX which principally was a kind of a

Pd(0)-CMC@Ce(OH)(4) organic/inorganic hybrid as highly active catalyst for the Suzuki-Miyaura reaction.

PubMed

Lin, Bijin; Liu, Xiaoping; Zhang, Zhuan; Chen, Yang; Liao, Xiaojian; Li, Yiqun

2017-07-01

A very easy sequential metathesis for the synthesis of Pd(II)-CMC@Ce(OH) 4 organic/inorganic hybrid and its application as effective pre-catalyst for the Suzuki-Miyaura reaction have been reported. It was found that the Pd nanoparticles (Pd NPs) were formed in situ in the course of the Suzuki-Miyaura couplings when Pd(II)-CMC@Ce(OH) 4 was used as a pre-catalyst. The activity of the Pd NPs in the reaction was enhanced synergistically by the unique redox properties (Ce 3+ /Ce 4+ ) of Ce(OH) 4 and coordination with carboxyl groups as well as free hydroxyl groups of the hybrid of CMC@Ce(OH) 4 . The results exhibit the Pd(0)-CMC@Ce(OH) 4 is super over Pd(II)@CMC, Pd(II)@CeO 2 , and Pd(II)@Ce(OH) 4 catalysts in the Suzuki-Miyaura reaction. Moreover, the catalyst could be easily separated by simple filtration and reused at least seven runs without losing its activity. Copyright © 2017 Elsevier Inc. All rights reserved.

Practical use of CMC-amended rhizobial inoculant for Mucuna pruriens cultivation to enhance the growth and protection against Macrophomina phaseolina.

PubMed

Aeron, Abhinav; Khare, Ekta; Kumar Arora, Naveen; Kumar Maheshwari, Dinesh

2012-01-01

In many parts of the world Mucuna pruriens is used as an important medicinal, forage and green manure crop. In the present investigation the effect of the addition of CMC in carrier during development of bioformulation on shelflife, plant growth promotive and biocontrol activity against Macrophomina phaseolina was screened taking M. pruriens as a test crop. Ensifer meliloti RMP6(Ery+Kan+) and Bradyrhizobium sp. BMP7(Tet+Kan+) (kanamycin resistance engineered by Tn5 transposon mutagenesis) used in the study showed production of siderophore, IAA, solubilizing phosphate and biocontrol of M. phaseolina. RMP6(Ery+Kan+) also showed ACC deaminase activity. The survival of both the strains in sawdust-based bioformulation was enhanced with an increase in the concentration of CMC from 0 to 1%. At 0% CMC Bradyrhizobium sp. BMP7(Tet+Kan+) showed more increase in nodule number/plant (500.00%) than E. meliloti RMP6(Ery+Kan+) (52.38%), over the control in M. phaseolina-infested soil. There was 185.94% and 59.52% enhancement in nodule number/plant by RMP6(Ery+Kan+) and BMP7(Tet+Kan+) with an increase in the concentration of CMC from 0% to 1% in the bioformulations. However further increase in concentration of CMC did not result in enhancement in survival of either the strains or nodule number/plant.

The Adsorption Capacity of GONs/CMC/Fe3O4 Magnetic Composite Microspheres and Applications for Purifying Dye Wastewater

PubMed Central

Lv, Shenghua; Zhu, Linlin; Li, Ying; Jia, Chunmao; Sun, Shiyu

2017-01-01

Graphene oxide nanosheets (GONs)/carboxymethyl chitosan (CMC)/Fe3O4 magnetic composite microspheres (MCMs) were prepared by enclosing Fe3O4 particles with CMC and GONs in turn. The microstructures of GONs and GONs/CMC/Fe3O4 MCMs were characterized by FTIR, XRD, TEM, and SEM. The effects of GON content, pH value, and adsorption time on the adsorption capacity of the MCMs were investigated. The results show that the GONs/CMC/Fe3O4 MCMs have a greater specific surface area and a strong adsorption capacity for dye wastewater. Meanwhile, the adsorption mechanism was investigated, and the results accorded with the pseudo-second-order kinetic model and the Freundlich isotherm model. The search results indicate that GONs/CMC/Fe3O4 MCMs can be used to purify dye wastewater and has an important potential use in the practical purification of dye wastewater. PMID:28772419

Carboxymethylcellulose (CMC) formed nanogels with branched poly(ethyleneimine) (bPEI) for inhibition of cytotoxicity in human MSCs as a gene delivery vehicles.

PubMed

Yang, Han Na; Park, Ji Sun; Jeon, Su Yeon; Park, Keun-Hong

2015-05-20

Specific vehicles are necessary for safe and efficient gene transfection into cells. Nano-type hydrogels (nanogel) comprising carboxymethylcellulose (CMC) complexed with branched type cationic poly(ethleneimine) (bPEI) were used as gene delivery vehicles. When complexes of CMC and bPEI were used in vitro, CMC showed nano-gel type properties, as shown by the results of a viscosity test, and bPEI showed low cytotoxicity comparing to bPEI alone. Together, these properties are shown to maintain high gene transfection efficiency. In viability experiments using three types of adult stem cells, cell viability varied depending on the branch form of PEI and whether or not it is in a complex with CMC. The gene delivery efficacy showed that the CMC nanogel complexed with bPEI (CMC-bPEI) showed more uptaking and gene transfection ability in hMSCs comparing to bPEI alone. In osteogenesis, the CMC-bPEI complexed with OSX pDNA showed more easy internalization than bPEI alone complexed with OSX pDNA in hMSCs. Specific genes and proteins related in osteogenic differentiation were expressed in hMSCs when the CMC-bPEI complexed with OSX pDNA was used. Copyright © 2015 Elsevier Ltd. All rights reserved.

Improvement of Fish Sauce Quality by Strain CMC5-3-1: A Novel Species of Staphylococcus sp.

PubMed

Udomsil, Natteewan; Rodtong, Sureelak; Tanasupawat, Somboon; Yongsawatdigul, Jirawat

2015-09-01

Staphylococcus sp. CMC5-3-1 and CMS5-7-5 isolated from fermented fish sauce at 3 to 7 mo, respectively, showed different characteristics on protein hydrolysis and volatile formation. These Gram-positive cocci were able to grow in up to 15% NaCl with the optimum at 0.5% to 5% NaCl in tryptic soy broth. Based on ribosomal 16S rRNA gene sequences, Staphylococcus sp. CMC5-3-1 and CMS5-7-5 showed 99.0% similarity to that of Staphylococcus piscifermentans JCM 6057(T) , but DNA-DNA relatedness was <30%, indicating that they were likely to be new species. DNA relatedness between these 2 strains was only 65%, suggesting that they also belonged to different species. The α-amino group content of 6-month-old fish sauce inoculated with Staphylococcus sp. CMC5-3-1 was 740.5 mM, which was higher than that inoculated by the strain CMS5-7-5 (662.14 mM, P < 0.05). Histamine was not produced during fermentations with both strains. Fish sauce inoculated with Staphylococcus sp. CMC5-3-1 showed the highest content of total glutamic acid (P < 0.05). The major volatile compound detected in fish sauce inoculated with Staphylococcus sp. CMC5-3-1 was 2-methypropanal, contributing to the desirable dark chocolate note. Staphylococcus sp. CMC5-3-1 could be applied as a starter culture to improve the umami and aroma of fish sauce. © 2015 Institute of Food Technologists®

The effect of CMC and arabic gum stabilizer combination on the characteristics of soursop velva (Annona muricata L.)

NASA Astrophysics Data System (ADS)

Parnanto, N. H. R.; Yudhistira, B.; Pertiwi, S. R.; Pangestika, A.

2018-03-01

The aims of this study were to determine the effect of the combination of CMC and Arabic Gum stabilizer toward the soursop velva characteristics and to determine the best stabilizer combination of soursop velva. This study was performed using Completely Randomized Design (CRD) with one factor: combination of CMC and Arabic Gum stabilizer using two sample replications and the analysis was repeated three times. The result showed that the use of the combination of CMC and Arabic Gum stabilizer gave a significant effect on the overrun value, melting power, total dissolved solids, moisture content, dietary fiber, taste, texture and overalls. Moreover, there were no significant effect on color and flavor of the soursop velva. The experiment showed that soursop velva F4 (3:1) was the best formula with overrun value 9.93%, the melting power was 22 minutes 52 seconds, the total dissolved solids 19,10°Brix, the moisture content 71.508%, dietary fiber 3.301% and it has sensory values of color, taste, flavor, texture, overall at 3.66, 3.267, 3.33, 4.06, 3.10 respectively.

FEAMAC-CARES Software Coupling Development Effort for CMC Stochastic-Strength-Based Damage Simulation

NASA Technical Reports Server (NTRS)

Nemeth, Noel N.; Bednarcyk, Brett A.; Pineda, Evan; Arnold, Steven; Mital, Subodh; Murthy, Pappu; Walton, Owen

2015-01-01

Reported here is a coupling of two NASA developed codes: CARES (Ceramics Analysis and Reliability Evaluation of Structures) with the MACGMC composite material analysis code. The resulting code is called FEAMACCARES and is constructed as an Abaqus finite element analysis UMAT (user defined material). Here we describe the FEAMACCARES code and an example problem (taken from the open literature) of a laminated CMC in off-axis loading is shown. FEAMACCARES performs stochastic-strength-based damage simulation response of a CMC under multiaxial loading using elastic stiffness reduction of the failed elements.

CMC Arthroplasty of the Thumb: A Review

PubMed Central

Ilyas, Asif; Thoder, Joseph J.

2007-01-01

Arthritis of the first carpometacarpal (CMC) joint of the hand is a common and often debilitating disease. Diagnosis can be readily made with history, physical exam, and radiographic evaluation. Patients with advanced disease who have failed conservative treatment modalities have multiple surgical options including ligament reconstruction, resection arthroplasty, silicone implantation, tendon interposition, or total joint arthroplasty. This article will describe the variety of approaches to treatment as well as the author’s preferred method. PMID:18780059

Immobilization and phytotoxicity of chromium in contaminated soil remediated by CMC-stabilized nZVI.

PubMed

Wang, Yu; Fang, Zhanqiang; Kang, Yuan; Tsang, Eric Pokeung

2014-06-30

The toxic effect of Cr(VI)-contaminated soil remediated by sodium carboxymethyl cellulose stabilized nanoscale zero-valent iron (CMC-stabilized nZVI) was assessed through in vitro toxicity and phytotoxicity tests. In vitro tests showed that 0.09 g L(-1) of Fe(0) nanoparticles (soil-to-solution ratio was 1 g:5 mL) significantly reduced the toxicity characteristic leaching procedure (TCLP) leachability and physiological based extraction test (PBET) bioaccessibility of Cr by 82% and 58%, respectively. Sequential extraction procedures (SEP) revealed that exchangeable (EX) Cr was completely converted to Fe-Mn oxides (OX) and organic matter (OM). Accordingly, phytotoxicity tests indicated that after 72-h remediation, Cr uptakes by edible rape and Chinese cabbage were suppressed by 61% and 36%, respectively. Moreover, no significant increase in Cr uptake was observed for either species after a 1-month static period for the amended soil. Regarding Fe absorption, germination and seedling growth, both plant species were significantly affected by CMC-nZVI-exposed soils. However, similar phytotoxicity tests conducted after 1 month showed an improvement in cultivation for both plants. Overall, this study demonstrated that CMC-nZVI could significantly enhance Cr immobilization, which reduced its leachability, bioavailability and bioaccumulation by plants. From a detoxification perspective, such remediation is technologically feasible and shows great potential in field applications. Copyright © 2014 Elsevier B.V. All rights reserved.

An exploratory examination of the relationship between motivational factors and the degree to which the higher education faculty integrate computer-mediated communication (CMC) tools into their courses

NASA Astrophysics Data System (ADS)

Murage, Francis Ndwiga

The stated research problem of this study was to examine the relationship between motivational factors and the degree to which the higher education faculty integrate CMC tools into their courses. The study population and sample involved higher education faculty teaching in science departments at one public university and three public colleges in the state of West Virginia (N = 153). A Likert-type rating scale survey was used to collect data based on the research questions. Two parts of the survey were adopted from previous studies while the other two were self-constructed. Research questions and hypothesis were analyzed using both descriptive and inferential analyses. The study results established a positive relationship between motivational factors and the degree the higher education faculty integrate CMC tools in their courses. The results in addition established that faculty are highly motivated to integrate CMC tools by intrinsic factors, moderately motivated by environmental factors and least motivated by extrinsic factors. The results also established that the most integrated CMC tools were those that support asynchronous methods of communication while the least integrated were those that support synchronous methods of communication. A major conclusion made was that members of higher education faculty are more likely to be motivated to integrate CMC tools into their courses by intrinsic factors rather than extrinsic or environmental factors. It was further concluded that intrinsic factors that supported and enhanced student learning as well as those that were altruistic in nature significantly influenced the degree of CMC integration. The study finally concluded that to larger extent, there is a relationship between motivational factors and the degree to which the higher education faculty integrate CMC tools in their courses. A major implication of this study was that institutions that wish to promote integration of CMC technologies should provide as much

EFL Writing Revision with Blind Expert and Peer Review Using a CMC Open Forum

ERIC Educational Resources Information Center

Wu, Wen-Chi Vivian; Petit, Emily; Chen, Ching-Huei

2015-01-01

This exploratory computer assisted-language learning (CALL) study used a computer-mediated communication (CMC) interface to allow English as a foreign language (EFL) writing students in classes at two universities to give each other anonymous peer feedback about essay-writing assignments reacting to selected news stories. Experts also provided…

Removal of uranium and fluorine from wastewater by double-functional microsphere adsorbent of SA/CMC loaded with calcium and aluminum

NASA Astrophysics Data System (ADS)

Wu, Liping; Lin, Xiaoyan; Zhou, Xingbao; Luo, Xuegang

2016-10-01

A novel dual functional microsphere adsorbent of alginate/carboxymethyl cellulose sodium composite loaded with calcium and aluminum (SA/CMC-Ca-Al) is prepared by an injection device to remove fluoride and uranium, respectively, from fluoro-uranium mixed aqueous solution. Batch experiments are performed at different conditions: pH, temperature, initial concentration and contact time. The results show that the maximum adsorption amount for fluoride is 35.98 mg/g at pH 2.0, 298.15 K concentration 100 mg/L, while that for uranium is 101.76 mg/g at pH 4.0, 298.15 K concentration 100 mg/L. Both of the adsorption process could be well described by Langmuir model. The adsorption kinetic data is fitted well with pseudo-first-order model for uranium and pseudo-second-order model for fluoride. Thermodynamic parameters are also evaluated, indicating that the adsorption of uranium on SA/CMC-Ca-Al is a spontaneous and exothermic process, while the removal of fluoride is non-spontaneous and endothermic process. The mechanism of modification and adsorption process on SA/CMC-Ca-Al is characterized by FT-IR, SEM, EDX and XPS. The results show that Ca (II) and Al (III) are loaded on SA/CMC through ion-exchange of sodium of SA/CMC. The coordination reaction and ion-exchange happen during the adsorption process between SA/CMC-Ca-Al and uranium, fluoride. Results suggest that the SA/CMC-Ca-Al adsorbent has a great potential in removing uranium and fluoride from aqueous solution.

A convergence algorithm for correlation of breech face images based on the congruent matching cells (CMC) method.

PubMed

Chen, Zhe; Song, John; Chu, Wei; Soons, Johannes A; Zhao, Xuezeng

2017-11-01

The Congruent Matching Cells (CMC) method was invented at the National Institute of Standards and Technology (NIST) for accurate firearm evidence identification and error rate estimation. The CMC method is based on the principle of discretization. The toolmark image of the reference sample is divided into correlation cells. Each cell is registered to the cell-sized area of the compared image that has maximum surface topography similarity. For each resulting cell pair, one parameter quantifies the similarity of the cell surface topography and three parameters quantify the pattern congruency of the registration position and orientation. An identification (declared match) requires a significant number of CMCs, that is, cell pairs that meet both similarity and pattern congruency requirements. The use of cell correlations reduces the effects of "invalid regions" in the compared image pairs and increases the correlation accuracy. The identification accuracy of the CMC method can be further improved by considering a feature named "convergence," that is, the tendency of the x-y registration positions of the correlated cell pairs to converge at the correct registration angle when comparing same-source samples at different relative orientations. In this paper, the difference of the convergence feature between known matching (KM) and known non-matching (KNM) image pairs is characterized, based on which an improved algorithm is developed for breech face image correlations using the CMC method. Its advantage is demonstrated by comparison with three existing CMC algorithms using four datasets. The datasets address three different brands of consecutively manufactured pistol slides, with significant differences in the distribution overlap of cell pair topography similarity for KM and KNM image pairs. For the same CMC threshold values, the convergence algorithm demonstrates noticeably improved results by reducing the number of false-positive or false-negative CMCs in a comparison

Connection Map for Compounds (CMC): A Server for Combinatorial Drug Toxicity and Efficacy Analysis.

PubMed

Liu, Lei; Tsompana, Maria; Wang, Yong; Wu, Dingfeng; Zhu, Lixin; Zhu, Ruixin

2016-09-26

Drug discovery and development is a costly and time-consuming process with a high risk for failure resulting primarily from a drug's associated clinical safety and efficacy potential. Identifying and eliminating inapt candidate drugs as early as possible is an effective way for reducing unnecessary costs, but limited analytical tools are currently available for this purpose. Recent growth in the area of toxicogenomics and pharmacogenomics has provided with a vast amount of drug expression microarray data. Web servers such as CMap and LTMap have used this information to evaluate drug toxicity and mechanisms of action independently; however, their wider applicability has been limited by the lack of a combinatorial drug-safety type of analysis. Using available genome-wide drug transcriptional expression profiles, we developed the first web server for combinatorial evaluation of toxicity and efficacy of candidate drugs named "Connection Map for Compounds" (CMC). Using CMC, researchers can initially compare their query drug gene signatures with prebuilt gene profiles generated from two large-scale toxicogenomics databases, and subsequently perform a drug efficacy analysis for identification of known mechanisms of drug action or generation of new predictions. CMC provides a novel approach for drug repositioning and early evaluation in drug discovery with its unique combination of toxicity and efficacy analyses, expansibility of data and algorithms, and customization of reference gene profiles. CMC can be freely accessed at http://cadd.tongji.edu.cn/webserver/CMCbp.jsp .

Synchronous and Asynchronous Text-Based CMC in Educational Contexts: A Review of Recent Research

ERIC Educational Resources Information Center

Johnson, Genevieve, Marie

2006-01-01

This paper presents a review of recent research that examines the relative instructional utility of text-based synchronous and asynchronous computer-mediated communication (CMC). As a mechanism for limiting the number of studies reviewed as well as controlling for emergent technologies, only research published since 2000 was reviewed. The goal was…

Preparation of CMC-g-P(SPMA) super adsorbent hydrogels: Exploring their capacity for MB removal from waste water.

PubMed

Salama, Ahmed

2018-01-01

A novel superadsorbent anionic hydrogel was synthesized by grafting of poly (3-sulfopropyl methacrylate), P(SPMA), onto carboxymethyl cellulose (CMC). CMC-g-P(SPMA) superadsorbent hydrogel was applied as an efficient and sustainable adsorbent to remove methylene blue (MB) from waste water. Batch adsorption experiments showed that the solution pH had an obvious effect on the adsorption capacity with an optimal sorption pH at 6. The CMC-g-P(SPMA) hydrogel had rapid adsorption kinetics for MB and the adsorption equilibrium reached within 40min. The adsorption kinetics were more accurately described by pseudo second-order model and the Langmuir-fitted adsorption isotherms revealed a maximum capacity of 1675mg/g. The current anionic hydrogel is reusable as the adsorption capacity remained at 89% level after five adsorption-desorption cycles. CMC-g-P(SPMA) hydrogel was presented as a sustainable promising adsorbent with high adsorption capacity and good regenerability for effective cationic dyes removal. Copyright © 2017 Elsevier B.V. All rights reserved.

SiC-CMC-Zircaloy-4 Nuclear Fuel Cladding Performance during 4-Point Tubular Bend Testing

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

IJ van Rooyen; WR Lloyd; TL Trowbridge

2013-09-01

The U.S. Department of Energy Office of Nuclear Energy (DOE NE) established the Light Water Reactor Sustainability (LWRS) program to develop technologies and other solutions to improve the reliability, sustain the safety, and extend the life of current reactors. The Advanced LWR Nuclear Fuel Development Pathway in the LWRS program encompasses strategic research focused on improving reactor core economics and safety margins through the development of an advanced fuel cladding system. Recent investigations of potential options for “accident tolerant” nuclear fuel systems point to the potential benefits of silicon carbide (SiC) cladding. One of the proposed SiC-based fuel cladding designsmore » being investigated incorporates a SiC ceramic matrix composite (CMC) as a structural material supplementing an internal Zircaloy-4 (Zr-4) liner tube, referred to as the hybrid clad design. Characterization of the advanced cladding designs will include a number of out-of-pile (nonnuclear) tests, followed by in-pile irradiation testing of the most promising designs. One of the out-of-pile characterization tests provides measurement of the mechanical properties of the cladding tube using four point bend testing. Although the material properties of the different subsystems (materials) will be determined separately, in this paper we present results of 4-point bending tests performed on fully assembled hybrid cladding tube mock-ups, an assembled Zr-4 cladding tube mock-up as a standard and initial testing results on bare SiC-CMC sleeves to assist in defining design parameters. The hybrid mock-up samples incorporated SiC-CMC sleeves fabricated with 7 polymer impregnation and pyrolysis (PIP) cycles. To provide comparative information; both 1- and 2-ply braided SiC-CMC sleeves were used in this development study. Preliminary stress simulations were performed using the BISON nuclear fuel performance code to show the stress distribution differences for varying lengths between

Predicting the development of diabetes using the product of triglycerides and glucose: the Chungju Metabolic Disease Cohort (CMC) study.

PubMed

Lee, Seung-Hwan; Kwon, Hyuk-Sang; Park, Yong-Moon; Ha, Hee-Sung; Jeong, Seung Hee; Yang, Hae Kyung; Lee, Jin-Hee; Yim, Hyeon-Woo; Kang, Moo-Il; Lee, Won-Chul; Son, Ho-Young; Yoon, Kun-Ho

2014-01-01

To determine whether the TyG index, a product of the levels of triglycerides and fasting plasma glucose (FPG) might be a valuable marker for predicting future diabetes. A total of 5,354 nondiabetic subjects who had completed their follow-up visit for evaluating diabetes status were selected from a large cohort of middle-aged Koreans in the Chungju Metabolic Disease Cohort study. The risk of diabetes was assessed according to the baseline TyG index, calculated as ln[fasting triglycerides (mg/dL) × FPG (mg/dL)/2]. The median follow-up period was 4.6 years. During the follow-up period, 420 subjects (7.8%) developed diabetes. The baseline values of the TyG index were significantly higher in these subjects compared with nondiabetic subjects (8.9 ± 0.6 vs. 8.6 ± 0.6; P<0.0001) and the incidence of diabetes increased in proportion to TyG index quartiles. After adjusting for age, gender, body mass index, waist circumference, systolic blood pressure, high-density lipoprotein (HDL)-cholesterol level, a family history of diabetes, smoking, alcohol drinking, education level and serum insulin level, the risk of diabetes onset was more than fourfold higher in the highest vs. the lowest quartile of the TyG index (relative risk, 4.095; 95% CI, 2.701-6.207). The predictive power of the TyG index was better than the triglyceride/HDL-cholesterol ratio or the homeostasis model assessment of insulin resistance. The TyG index, a simple measure reflecting insulin resistance, might be useful in identifying individuals at high risk of developing diabetes.

Predicting the Development of Diabetes Using the Product of Triglycerides and Glucose: The Chungju Metabolic Disease Cohort (CMC) Study

PubMed Central

Lee, Seung-Hwan; Kwon, Hyuk-Sang; Park, Yong-Moon; Ha, Hee-Sung; Jeong, Seung Hee; Yang, Hae Kyung; Lee, Jin-Hee; Yim, Hyeon-Woo; Kang, Moo-Il; Lee, Won-Chul; Son, Ho-Young; Yoon, Kun-Ho

2014-01-01

Background To determine whether the TyG index, a product of the levels of triglycerides and fasting plasma glucose (FPG) might be a valuable marker for predicting future diabetes. Methods A total of 5,354 nondiabetic subjects who had completed their follow-up visit for evaluating diabetes status were selected from a large cohort of middle-aged Koreans in the Chungju Metabolic Disease Cohort study. The risk of diabetes was assessed according to the baseline TyG index, calculated as ln[fasting triglycerides (mg/dL) × FPG (mg/dL)/2]. The median follow-up period was 4.6 years. Results During the follow-up period, 420 subjects (7.8%) developed diabetes. The baseline values of the TyG index were significantly higher in these subjects compared with nondiabetic subjects (8.9±0.6 vs. 8.6±0.6; P<0.0001) and the incidence of diabetes increased in proportion to TyG index quartiles. After adjusting for age, gender, body mass index, waist circumference, systolic blood pressure, high-density lipoprotein (HDL)-cholesterol level, a family history of diabetes, smoking, alcohol drinking, education level and serum insulin level, the risk of diabetes onset was more than fourfold higher in the highest vs. the lowest quartile of the TyG index (relative risk, 4.095; 95% CI, 2.701–6.207). The predictive power of the TyG index was better than the triglyceride/HDL-cholesterol ratio or the homeostasis model assessment of insulin resistance. Conclusions The TyG index, a simple measure reflecting insulin resistance, might be useful in identifying individuals at high risk of developing diabetes. PMID:24587359

Estimation of AOT and SDS CMC in a methanol using conductometry, viscometry and pyrene fluorescence spectroscopy methods

NASA Astrophysics Data System (ADS)

Mitsionis, Anastasios I.; Vaimakis, Tiverios C.

2012-09-01

Critical micelle concentration (CMC) of two anionic surfactants in methanol was estimated using conductometry, viscometry and pyrene fluorescence spectroscopy methods. The surfactants used, were sodium bis(2-ethylhexyl) sulfosuccinate (Aerosol-OT, AOT) and sodium dodecyl sulfate (SDS) dispersed in pure methanol. The CMC determination was evaluated in room temperature. The results have shown nearly similar concentrations.

Novel Anti-Adhesive CMC-PE Hydrogel Significantly Enhanced Morphological and Physiological Recovery after Surgical Decompression in an Animal Model of Entrapment Neuropathy.

PubMed

Urano, Hideki; Iwatsuki, Katsuyuki; Yamamoto, Michiro; Ohnisi, Tetsuro; Kurimoto, Shigeru; Endo, Nobuyuki; Hirata, Hitoshi

2016-01-01

We developed a novel hydrogel derived from sodium carboxymethylcellulose (CMC) in which phosphatidylethanolamine (PE) was introduced into the carboxyl groups of CMC to prevent perineural adhesions. This hydrogel has previously shown excellent anti-adhesive effects even after aggressive internal neurolysis in a rat model. Here, we confirmed the effects of the hydrogel on morphological and physiological recovery after nerve decompression. We prepared a rat model of chronic sciatic nerve compression using silicone tubing. Morphological and physiological recovery was confirmed at one, two, and three months after nerve decompression by assessing motor conduction velocity (MCV), the wet weight of the tibialis anterior muscle and morphometric evaluations of nerves. Electrophysiology showed significantly quicker recovery in the CMC-PE group than in the control group (24.0 ± 3.1 vs. 21.0± 2.1 m/s (p < 0.05) at one months and MCV continued to be significantly faster thereafter. Wet muscle weight at one month significantly differed between the CMC-PE (BW) and control groups (0.148 ± 0.020 vs. 0.108 ± 0.019%BW). The mean wet muscle weight was constantly higher in the CMC-PE group than in the control group throughout the experimental period. The axon area at one month was twice as large in the CMC-PE group compared with the control group (24.1 ± 17.3 vs. 12.3 ± 9 μm2) due to the higher ratio of axons with a larger diameter. Although the trend continued throughout the experimental period, the difference decreased after two months and was not statistically significant at three months. Although anti-adhesives can reduce adhesion after nerve injury, their effects on morphological and physiological recovery after surgical decompression of chronic entrapment neuropathy have not been investigated in detail. The present study showed that the new anti-adhesive CMC-PE gel can accelerate morphological and physiological recovery of nerves after decompression surgery.

Enhanced electrochemical properties of LiFePO4 (LFP) cathode using the carboxymethyl cellulose lithium (CMC-Li) as novel binder in lithium-ion battery.

PubMed

Qiu, Lei; Shao, Ziqiang; Wang, Daxiong; Wang, Wenjun; Wang, Feijun; Wang, Jianquan

2014-10-13

Novel water-based binder CMC-Li is synthesized using cotton as raw material. The mechanism of the CMC-Li as a binder is reported. Electrochemical properties of batteries cathodes based on commercially available lithium iron phosphate (LiFePO4, LFP) and CMC-Li as a water-soluble binder are investigated. CMC-Li is a novel lithium-ion binder. Compare with conventional poly(vinylidene fluoride) (PVDF) binder, and the battery with CMC-Li as the binder retained 97.8% of initial reversible capacity after 200 cycles at 176 mAh g(-1), which is beyond the theoretical specific capacity of LFP. Constant current charge-discharge test results demonstrate that the LFP electrode using CMC-Li as the binder has the highest rate capability, follow closely by that using PVDF binder. The batteries have good electrochemical property, outstanding pollution-free and excellent stability. Copyright © 2014 Elsevier Ltd. All rights reserved.

Long term impacts of CMC/nZVI amendment injection on organohalide-respiring microbial communities at a chlorinated solvent field site

NASA Astrophysics Data System (ADS)

Kocur, C. M.; Lomheim, L.; Boparai, H. K.; Chowdhury, A. I.; Weber, K.; Austrins, L. M.; Sleep, B.; O'Carroll, D. M.; Edwards, E.

2014-12-01

Injection of carboxymethyl-cellulose stabilized nanoscale Zero Valent Iron (CMC/nZVI) has received significant attention in the last decade as an emerging alternative for in-situ remediation of chlorinated solvents and other recalcitrant compounds. There has also been some indication that injection of nZVI will create conditions that will stimulate in-situ microbial populations, leading to further contaminant degradation. Carboxy-methyl cellulose (CMC) is commonly used for nZVI synthesis as it provides steric stabilization for the nanoparticles, however, the CMC is equally important as a subsurface amendment as it may act as a fermentable substrate for microorganisms in-situ. In this study, microbial communities were monitored over a 2.5 year period following the injection of CMC/nZVI at a chlorinated solvent remediation site. Dehalococcoides spp. genetic markers and vinyl chloride reductase genes (vcrA) were targeted in the 16s RNA using quantitative polymerase chain reaction (qPCR). This analysis was complimented with a suite of aqueous chlorinated ethene, ethane, and methane compounds to monitor degradation. Following the injection of CMC/nZVI a decline of parent chlorinated compound concentrations was observed as well as the emergence of daughter products. A period of abiotic nZVI oxidation is believed to be responsible for a portion of the degradation at the site, however, a prolonged period of contaminant degradation followed and is believed to be the result of organohalide-respiring microorganisms native to the site. Further analysis was performed on the microbial samples using 454 pyrotag sequencing of amplified 16S rRNA genes to obtain the genetic profile of the microbial community. Of particular interest within this large genomic profile is the characterization of the stable population of important organohalide-respiring microorganisms on site. Results suggest that there is a distinctly different response in the organohalide-respiring microbial community

Compact, Lightweight, Ceramic Matrix Composite (CMC) Based Acoustic Liners for Reducing Subsonic Jet Aircraft Engine Noise

NASA Technical Reports Server (NTRS)

Kiser, J. Douglas; Grady, Joseph E.; Miller, Christopher J.; Hultgren, Lennart S.; Jones, Michael G.

2016-01-01

Recent developments have reduced fan and jet noise contributions to overall subsonic aircraft jet-engine noise. Now, aircraft designers are turning their attention toward reducing engine core noise. The NASA Glenn Research Center and NASA Langley Research Center have teamed to investigate the development of a compact, lightweight acoustic liner based on oxide/oxide ceramic matrix composite (CMC) materials. The NASA team has built upon an existing oxide/oxide CMC sandwich structure concept that provides monotonal noise reduction. Oxide/oxide composites have good high temperature strength and oxidation resistance, which could allow them to perform as core liners at temperatures up to 1000C (1832F), and even higher depending on the selection of the composite constituents. NASA has initiated the evaluation of CMC-based liners that use cells of different lengths (variable-depth channels) or effective lengths to achieve broadband noise reduction. Reducing the overall liner thickness is also a major goal, to minimize the volume occupied by the liner. As a first step toward demonstrating the feasibility of our concepts, an oxide/oxide CMC acoustic testing article with different channel lengths was tested. Our approach, summary of test results, current status, and goals for the future are reported.

Fabrication and characterization of tea polyphenols loaded pullulan-CMC electrospun nanofiber for fruit preservation.

PubMed

Shao, Ping; Niu, Ben; Chen, Hangjun; Sun, Peilong

2018-02-01

Edible packaging films using polymer for food preservation have been developed for a long time. In this study, the effects of different concentrations (0.5%, 1%, 1.5%, w/v) of tea polyphenols incorporated into pullulan-Carboxymethylcellulose sodium (Pul-CMC) solutions on electrospun nanofiber films were evaluated. The fiber size distribution was characterized by scanning electron microscopy. The morphological features of nanofibers were modulated through adjusting process parameters (e.g. concentration of polymer solution, applied voltage and feeding rate). Increasing the applied voltage from 19 to 21kV and the feed rate from 0.36 to 0.6mL/h leads to a reduction in mean fiber diameter. Fruit packaging potential was evaluated using strawberry. The pullulan-CMC-TP nanofibers significantly decreased weight loss and maintained the firmness of the strawberries, and improved the quality of the fruit during storage. The findings demonstrate a facile packaging route to improve food sustainability and reduce waste. Copyright © 2017 Elsevier B.V. All rights reserved.

Canonical Measure of Correlation (CMC) and Canonical Measure of Distance (CMD) between sets of data. Part 3. Variable selection in classification.

PubMed

Ballabio, Davide; Consonni, Viviana; Mauri, Andrea; Todeschini, Roberto

2010-01-11

In multivariate regression and classification issues variable selection is an important procedure used to select an optimal subset of variables with the aim of producing more parsimonious and eventually more predictive models. Variable selection is often necessary when dealing with methodologies that produce thousands of variables, such as Quantitative Structure-Activity Relationships (QSARs) and highly dimensional analytical procedures. In this paper a novel method for variable selection for classification purposes is introduced. This method exploits the recently proposed Canonical Measure of Correlation between two sets of variables (CMC index). The CMC index is in this case calculated for two specific sets of variables, the former being comprised of the independent variables and the latter of the unfolded class matrix. The CMC values, calculated by considering one variable at a time, can be sorted and a ranking of the variables on the basis of their class discrimination capabilities results. Alternatively, CMC index can be calculated for all the possible combinations of variables and the variable subset with the maximal CMC can be selected, but this procedure is computationally more demanding and classification performance of the selected subset is not always the best one. The effectiveness of the CMC index in selecting variables with discriminative ability was compared with that of other well-known strategies for variable selection, such as the Wilks' Lambda, the VIP index based on the Partial Least Squares-Discriminant Analysis, and the selection provided by classification trees. A variable Forward Selection based on the CMC index was finally used in conjunction of Linear Discriminant Analysis. This approach was tested on several chemical data sets. Obtained results were encouraging.

CCARES: A computer algorithm for the reliability analysis of laminated CMC components

NASA Technical Reports Server (NTRS)

Duffy, Stephen F.; Gyekenyesi, John P.

1993-01-01

Structural components produced from laminated CMC (ceramic matrix composite) materials are being considered for a broad range of aerospace applications that include various structural components for the national aerospace plane, the space shuttle main engine, and advanced gas turbines. Specifically, these applications include segmented engine liners, small missile engine turbine rotors, and exhaust nozzles. Use of these materials allows for improvements in fuel efficiency due to increased engine temperatures and pressures, which in turn generate more power and thrust. Furthermore, this class of materials offers significant potential for raising the thrust-to-weight ratio of gas turbine engines by tailoring directions of high specific reliability. The emerging composite systems, particularly those with silicon nitride or silicon carbide matrix, can compete with metals in many demanding applications. Laminated CMC prototypes have already demonstrated functional capabilities at temperatures approaching 1400 C, which is well beyond the operational limits of most metallic materials. Laminated CMC material systems have several mechanical characteristics which must be carefully considered in the design process. Test bed software programs are needed that incorporate stochastic design concepts that are user friendly, computationally efficient, and have flexible architectures that readily incorporate changes in design philosophy. The CCARES (Composite Ceramics Analysis and Reliability Evaluation of Structures) program is representative of an effort to fill this need. CCARES is a public domain computer algorithm, coupled to a general purpose finite element program, which predicts the fast fracture reliability of a structural component under multiaxial loading conditions.

Effects of Online Interaction via Computer-Mediated Communication (CMC) Tools on an E-Mathematics Learning Outcome

ERIC Educational Resources Information Center

Okonta, Olomeruom

2010-01-01

Recent research studies in open and distance learning have focused on the differences between traditional learning versus online learning, the benefits of computer-mediated communication (CMC) tools in an e-learning environment, and the relationship between online discussion posts and students' achievement. In fact, there is an extant…

Initial development of goCMC: a GPU-oriented fast cross-platform Monte Carlo engine for carbon ion therapy

PubMed Central

Qin, Nan; Pinto, Marco; Tian, Zhen; Dedes, Georgios; Pompos, Arnold; Jiang, Steve B.; Parodi, Katia; Jia, Xun

2017-01-01

Monte Carlo (MC) simulation is considered as the most accurate method for calculation of absorbed dose and fundamental physics quantities related to biological effects in carbon ion therapy. To improve its computational efficiency, we have developed a GPU-oriented fast MC package named goCMC, for carbon therapy. goCMC simulates particle transport in voxelized geometry with kinetic energy up to 450 MeV/u. Class II condensed history simulation scheme with a continuous slowing down approximation was employed. Energy straggling and multiple scattering were modeled. δ-electrons were terminated with their energy locally deposited. Four types of nuclear interactions were implemented in goCMC, i.e., carbon-hydrogen, carbon-carbon, carbon-oxygen and carbon-calcium inelastic collisions. Total cross section data from Geant4 were used. Secondary particles produced in these interactions were sampled according to particle yield with energy and directional distribution data derived from Geant4 simulation results. Secondary charged particles were transported following the condensed history scheme, whereas secondary neutral particles were ignored. goCMC was developed under OpenCL framework and is executable on different platforms, e.g. GPU and multi-core CPU. We have validated goCMC with Geant4 in cases with different beam energy and phantoms including four homogeneous phantoms, one heterogeneous half-slab phantom, and one patient case. For each case 3 × 107 carbon ions were simulated, such that in the region with dose greater than 10% of maximum dose, the mean relative statistical uncertainty was less than 1%. Good agreements for dose distributions and range estimations between goCMC and Geant4 were observed. 3D gamma passing rates with 1%/1 mm criterion were over 90% within 10%) isodose line except in two extreme cases, and those with 2%/1 mm criterion were all over 96%. Efficiency and code portability were tested with different GPUs and CPUs. Depending on the beam energy and

Initial development of goCMC: a GPU-oriented fast cross-platform Monte Carlo engine for carbon ion therapy

NASA Astrophysics Data System (ADS)

Qin, Nan; Pinto, Marco; Tian, Zhen; Dedes, Georgios; Pompos, Arnold; Jiang, Steve B.; Parodi, Katia; Jia, Xun

2017-05-01

Monte Carlo (MC) simulation is considered as the most accurate method for calculation of absorbed dose and fundamental physics quantities related to biological effects in carbon ion therapy. To improve its computational efficiency, we have developed a GPU-oriented fast MC package named goCMC, for carbon therapy. goCMC simulates particle transport in voxelized geometry with kinetic energy up to 450 MeV u-1. Class II condensed history simulation scheme with a continuous slowing down approximation was employed. Energy straggling and multiple scattering were modeled. δ-electrons were terminated with their energy locally deposited. Four types of nuclear interactions were implemented in goCMC, i.e. carbon-hydrogen, carbon-carbon, carbon-oxygen and carbon-calcium inelastic collisions. Total cross section data from Geant4 were used. Secondary particles produced in these interactions were sampled according to particle yield with energy and directional distribution data derived from Geant4 simulation results. Secondary charged particles were transported following the condensed history scheme, whereas secondary neutral particles were ignored. goCMC was developed under OpenCL framework and is executable on different platforms, e.g. GPU and multi-core CPU. We have validated goCMC with Geant4 in cases with different beam energy and phantoms including four homogeneous phantoms, one heterogeneous half-slab phantom, and one patient case. For each case 3× {{10}7} carbon ions were simulated, such that in the region with dose greater than 10% of maximum dose, the mean relative statistical uncertainty was less than 1%. Good agreements for dose distributions and range estimations between goCMC and Geant4 were observed. 3D gamma passing rates with 1%/1 mm criterion were over 90% within 10% isodose line except in two extreme cases, and those with 2%/1 mm criterion were all over 96%. Efficiency and code portability were tested with different GPUs and CPUs. Depending on the beam

Initial development of goCMC: a GPU-oriented fast cross-platform Monte Carlo engine for carbon ion therapy.

PubMed

Qin, Nan; Pinto, Marco; Tian, Zhen; Dedes, Georgios; Pompos, Arnold; Jiang, Steve B; Parodi, Katia; Jia, Xun

2017-05-07

Monte Carlo (MC) simulation is considered as the most accurate method for calculation of absorbed dose and fundamental physics quantities related to biological effects in carbon ion therapy. To improve its computational efficiency, we have developed a GPU-oriented fast MC package named goCMC, for carbon therapy. goCMC simulates particle transport in voxelized geometry with kinetic energy up to 450 MeV u -1 . Class II condensed history simulation scheme with a continuous slowing down approximation was employed. Energy straggling and multiple scattering were modeled. δ-electrons were terminated with their energy locally deposited. Four types of nuclear interactions were implemented in goCMC, i.e. carbon-hydrogen, carbon-carbon, carbon-oxygen and carbon-calcium inelastic collisions. Total cross section data from Geant4 were used. Secondary particles produced in these interactions were sampled according to particle yield with energy and directional distribution data derived from Geant4 simulation results. Secondary charged particles were transported following the condensed history scheme, whereas secondary neutral particles were ignored. goCMC was developed under OpenCL framework and is executable on different platforms, e.g. GPU and multi-core CPU. We have validated goCMC with Geant4 in cases with different beam energy and phantoms including four homogeneous phantoms, one heterogeneous half-slab phantom, and one patient case. For each case [Formula: see text] carbon ions were simulated, such that in the region with dose greater than 10% of maximum dose, the mean relative statistical uncertainty was less than 1%. Good agreements for dose distributions and range estimations between goCMC and Geant4 were observed. 3D gamma passing rates with 1%/1 mm criterion were over 90% within 10% isodose line except in two extreme cases, and those with 2%/1 mm criterion were all over 96%. Efficiency and code portability were tested with different GPUs and CPUs. Depending on the

An Investigation of Mixed Student Reactions to CMC for Instructional Purposes.

ERIC Educational Resources Information Center

Lu, Xin-An

Research indicates that computer-mediated communication (CMC) is a great motivator of learning for the student (e.g., Gatlin-Watts, Arn, & Kordsmeier, 1998). However, the author's experience communicating with students through the Web indicates very divided student reactions to this manner of communication. In view of a relative lack of literature…

Recurrent furunculosis: Efficacy of the CMC regimen--skin disinfection (chlorhexidine), local nasal antibiotic (mupirocin), and systemic antibiotic (clindamycin).

PubMed

Davido, Benjamin; Dinh, Aurélien; Salomon, Jérôme; Roux, Anne Laure; Gosset-Woimant, Marine; Pierre, Isabelle; Perronne, Christian; Bernard, Louis

2013-11-01

The treatment of recurrent furunculosis is poorly documented and represents a public health challenge. The medical care of this disease is often disappointing, especially as the disease evolution is uncertain and relapses occur. We report the efficacy and safety of our CMC regimen: skin disinfection (chlorhexidine), local nasal antibiotic (mupirocin), and systemic antibiotic (clindamycin). Patients attending our institution during the period 2006-2012 for recurrent furunculosis (≥ 4 episodes/y) were enrolled in the study. Clinical and bacteriological data were collected. Staphylococcus aureus colonization was also investigated in close contacts, and carriers were treated. Patients were treated with the CMC regimen: skin disinfection with chlorhexidine for 21 days, nasal mupirocin ointment for 5 days, and oral clindamycin 1800-2400 mg for 21 days. Nineteen patients were included. Their mean age was 36 ± 14.5 y and the male to female sex ratio was 1.1. Screening swabs from all sites were S. aureus-positive in 63% (n = 12), including 4 methicillin-resistant S. aureus (MRSA). Before the CMC regimen, the median time to relapse was 31 days (mean 52 days). The mean number of recurrences was 5.5 ± 2.4/y. After the CMC regimen, among 16 patients who had a complete follow-up, 14 were healed beyond 9 months. Two recurrences occurred, 1 in an MRSA carrier and 1 in a patient with an insufficiently treated dermatosis. No serious side effect occurred that required the cessation of treatment. There are 2 major routes involved in recurrent furunculosis: risk factors and staphylococcal colonization of close contacts. Our procedure is safe and effective, with 87% remission beyond 9 months. It merits testing on larger numbers of participants.

Methodology Series Module 1: Cohort Studies

PubMed Central

Setia, Maninder Singh

2016-01-01

Cohort design is a type of nonexperimental or observational study design. In a cohort study, the participants do not have the outcome of interest to begin with. They are selected based on the exposure status of the individual. They are then followed over time to evaluate for the occurrence of the outcome of interest. Some examples of cohort studies are (1) Framingham Cohort study, (2) Swiss HIV Cohort study, and (3) The Danish Cohort study of psoriasis and depression. These studies may be prospective, retrospective, or a combination of both of these types. Since at the time of entry into the cohort study, the individuals do not have outcome, the temporality between exposure and outcome is well defined in a cohort design. If the exposure is rare, then a cohort design is an efficient method to study the relation between exposure and outcomes. A retrospective cohort study can be completed fast and is relatively inexpensive compared with a prospective cohort study. Follow-up of the study participants is very important in a cohort study, and losses are an important source of bias in these types of studies. These studies are used to estimate the cumulative incidence and incidence rate. One of the main strengths of a cohort study is the longitudinal nature of the data. Some of the variables in the data will be time-varying and some may be time independent. Thus, advanced modeling techniques (such as fixed and random effects models) are useful in analysis of these studies. PMID:26955090

Methodology Series Module 1: Cohort Studies.

PubMed

Setia, Maninder Singh

2016-01-01

Cohort design is a type of nonexperimental or observational study design. In a cohort study, the participants do not have the outcome of interest to begin with. They are selected based on the exposure status of the individual. They are then followed over time to evaluate for the occurrence of the outcome of interest. Some examples of cohort studies are (1) Framingham Cohort study, (2) Swiss HIV Cohort study, and (3) The Danish Cohort study of psoriasis and depression. These studies may be prospective, retrospective, or a combination of both of these types. Since at the time of entry into the cohort study, the individuals do not have outcome, the temporality between exposure and outcome is well defined in a cohort design. If the exposure is rare, then a cohort design is an efficient method to study the relation between exposure and outcomes. A retrospective cohort study can be completed fast and is relatively inexpensive compared with a prospective cohort study. Follow-up of the study participants is very important in a cohort study, and losses are an important source of bias in these types of studies. These studies are used to estimate the cumulative incidence and incidence rate. One of the main strengths of a cohort study is the longitudinal nature of the data. Some of the variables in the data will be time-varying and some may be time independent. Thus, advanced modeling techniques (such as fixed and random effects models) are useful in analysis of these studies.

Computed Tomography and Thermography Increases CMC Material and Process Development Efficiency and Testing Effectiveness

NASA Technical Reports Server (NTRS)

Effinger, Michael; Beshears, Ron; Hufnagle, David; Walker, James; Russell, Sam; Stowell, Bob; Myers, David

2002-01-01

Nondestructive characterization techniques have been used to steer development and testing of CMCs. Computed tomography is used to determine the volumetric integrity of the CMC plates and components. Thermography is used to determine the near surface integrity of the CMC plates and components. For process and material development, information such as density uniformity, part delamination, and dimensional tolerance conformity is generated. The information from the thermography and computed tomography is correlated and then specimen cutting maps are superimposed on the thermography images. This enables for tighter data and potential explanation of off nominal test data. Examples of nondestructive characterization utilization to make decisions in process and material development and testing are presented.

Determination of Consciousness and Awareness of the Public in Lefka about the Cyprus Mining Corporation (CMC)

ERIC Educational Resources Information Center

Gündüz, Serife; Erbulut, Can; Öznacar, Behcet; Bastas, Mert

2016-01-01

Supporting the increase of environmental consciousness with environmental education is always important in order to make healthy recommendations specific to the countries. Aim of this study is to determine the awareness and consciousness of the local community against the environmental pollution caused by the CMC mine by survey technique. 123…

The Effect of Fiber Architecture on Matrix Cracking in Sic/sic Cmc's

NASA Technical Reports Server (NTRS)

Morscher, Gregory N.

2005-01-01

Applications incorporating silicon carbide fiber reinforced silicon carbide matrix composites (CMC's) will require a wide range of fiber architectures in order to fabricate complex shape. The stress-strain response of a given SiC/SiC system for different architectures and orientations will be required in order to design and effectively life-model future components. The mechanism for non-linear stress-strain behavior in CMC's is the formation and propagation of bridged-matrix cracks throughout the composite. A considerable amount of understanding has been achieved for the stress-dependent matrix cracking behavior of SiC fiber reinforced SiC matrix systems containing melt-infiltrated Si. This presentation will outline the effect of 2D and 3D architectures and orientation on stress-dependent matrix-cracking and how this information can be used to model material behavior and serve as the starting point foe mechanistic-based life-models.

NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 38: Computer Mediated Communication (CMC) and the communication of technical information in aerospace

NASA Technical Reports Server (NTRS)

Murphy, Daniel J.; Pinelli, Thomas E.

1994-01-01

This paper discusses the use of computers as a medium for communication (CMC) used by aerospace engineers and scientists to obtain and/or provide technical information related to research and development activities. The data were obtained from a questionnaire survey that yielded 1006 mail responses. In addition to communication media, the research also investigates degrees of task uncertainty, environmental complexity, and other relevant variables that can affect aerospace workers' information-seeking strategies. While findings indicate that many individuals report CMC is an important function in their communication patterns, the research indicates that CMC is used less often and deemed less valuable than other more conventional media, such as paper documents, group meetings, telephone and face-to-face conversations. Fewer than one third of the individuals in the survey account for nearly eighty percent of the reported CMC use, and another twenty percent indicate they do not use the medium at all, its availability notwithstanding. These preliminary findings suggest that CMC is not as pervasive a communication medium among aerospace workers as the researcher expect a priori. The reasons underlying the reported media use are not yet fully known, and this suggests that continuing research in this area may be valuable.

Preclinical anti-tumor activity of antibody-targeted chemotherapy with CMC-544 (inotuzumab ozogamicin), a CD22-specific immunoconjugate of calicheamicin, compared with non-targeted combination chemotherapy with CVP or CHOP.

PubMed

DiJoseph, John F; Dougher, Maureen M; Evans, Deborah Y; Zhou, Bin-Bing; Damle, Nitin K

2011-04-01

CMC-544 (inotuzumab ozogamicin) is a CD22-specific immunoconjugate of calicheamicin currently being evaluated in patients with non-Hodgkin's B-cell lymphoma (BCL). CHOP and CVP represent untargeted combination chemotherapy comprised of cyclophosphamide, vincristine and prednisone with or without doxorubicin, commonly used in the treatment of NHL. Here, we describe anti-tumor efficacy of CMC-544, CHOP or CVP against human BCL xenografts. In vitro, human BCLs were cultured with CMC-544 or individual constituents of CHOP for inhibition of their growth. In vivo, immunocompromised mice with established BCL xenografts were administered CHOP, CVP or CMC-544 to monitor their survival and BCL growth. In vitro, CMC-544 was more potent in causing growth inhibition of various BCL than cyclophosphamide, doxorubicin, vincristine or dexamethasone. In vivo, treatment with CHOP or CVP inhibited growth of BCL xenografts for up to 40 days after which BCL relapsed. Tumor growth inhibition by CMC-544 (>100 days) lasted longer than that by CHOP or CVP. BCL xenografts that relapsed after the treatment with CHOP or CVP were far less responsive to CHOP or CVP re-treatment but regressed upon subsequent treatment with CMC-544. CVP could be co-administered with suboptimal doses of CMC-544, while CHOP could be administered on alternant days with CMC-544 to cause enhanced regression of established BCL xenografts. Preclinically, CMC-544 provides greater therapeutic benefit than CVP or CHOP against BCL xenografts. CMC-544 may also be co-administered with standard chemotherapeutic regimens in the treatment of B-NHL for superior anti-tumor activity.

Reliability Growth of Tactical Coolers at CMC Electronics Cincinnati: 1/5-Watt Cooler Test Report

NASA Astrophysics Data System (ADS)

Kuo, D. T.; Lody, T. D.

2004-06-01

CMC Electronics Cincinnati (CMC) is conducting a reliability growth program to extend the life of tactical Stirling-cycle cryocoolers. The continuous product improvement processes consist of testing production coolers to failure, determining the root cause, incorporating improvements and verification. The most recent life data for the 1/5-Watt Cooler (Model B512B) is presented with a discussion of leading root causes and potential improvements. The mean time to failure (MTTF) life of the coolers was found to be 22,552 hours with the root cause of failure attributed to the accumulation of methane and carbon dioxide in the cooler and the wear of the piston.

Volar denervation and osteophyte resection to relieve volar CMC joint pain.

PubMed

Dellon, A Lee

2017-01-01

At mean 125.6 months, pain was reduced from mean of 8.7 to 0.67, p  < .001. Each of three patients, two of whom were musicians, returned to full professional ability. It is concluded that volar CMC joint denervation is a useful procedure, preserving joint function and relieving pain long-term.

Manganese chloride tetrahydrate (CMC-001) enhanced liver MRI: evaluation of efficacy and safety in healthy volunteers.

PubMed

Albiin, Nils; Kartalis, Nikolaos; Bergquist, Annika; Sadigh, Bita; Brismar, Torkel B

2012-10-01

To evaluate the efficacy of three dose levels of the oral hepatobiliary manganese-based magnetic resonance imaging (MRI) contrast agent CMC-001, and assess its safety profile and patient acceptability. After ethics committee approval, 32 healthy volunteers (males/females: 18/14) were included. Liver MRI was performed before and 3 h after ingestion of 0.8, 0.4, and 0.2 g of CMC-001 on separate occasions. Liver-to-muscle signal intensity (SI) ratio from baseline to post-contrast and image quality was assessed. Adverse drug reactions/adverse events (ADRs/AEs) and clinico-laboratory tests were monitored. The increase in liver-to-muscle SI ratio was significantly higher after 0.8 g (0.696) compared to 0.4 g (0.458) and 0.2 g (0.223) (in all pair-wise comparisons, P < 0.0001). The overall image quality was superior after 0.8 g. ADRs/AEs were dose-related and predominantly of mild intensity. Liver MRI using 0.8 g CMC-001 has the highest efficacy and still acceptable ADRs and should therefore be preferred.

Development and testing of CMC components for automotive gas turbine engines

NASA Technical Reports Server (NTRS)

Khandelwal, Pramod K.

1991-01-01

Ceramic matrix composite (CMC) materials are currently being developed and evaluated for advanced gas turbine engine components because of their high specific strength and resistance to catastrophic failure. Components with 2D and 3D composite architectures have been successfully designed and fabricated. This is an overview of the test results for a backplate, combustor, and a rotor.

Risk Factors for 30-Day Complications After Thumb CMC Joint Arthroplasty: An American College of Surgeons National Surgery Quality Improvement Program Study.

PubMed

Shah, Kalpit N; Defroda, Steven F; Wang, Bo; Weiss, Arnold-Peter C

2017-12-01

The first carpometacarpal (CMC) joint is a common site of osteoarthritis, with arthroplasty being a common procedure to provide pain relief and improve function with low complications. However, little is known about risk factors that may predispose a patient for postoperative complications. All CMC joint arthroplasty from 2005 to 2015 in the prospectively collected American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database were identified. Bivariate testing and multiple logistic regressions were performed to determine which patient demographics, surgical variables and medical comorbidities were significant predictors for complications. These included wound related, cardiopulmonary, neurological and renal complications, return to the operating room (OR) and readmission. A total of 3344 patients were identified from the database. Of those, 45 patients (1.3%) experienced a complication including wound issues (0.66%), return to the OR (0.15%) and readmission (0.27%) amongst others. When performing bivariate analysis, age over 65, American Society of Anesthesiologists (ASA) Class, diabetes and renal dialysis were significant risk factors. Multiple logistic regression after adjusting for confounding factors demonstrated that insulin-dependent diabetes and ASA Class 4 had a strong trend while renal dialysis was a significant risk factor. CMC arthroplasty has a very low overall complication rate of 1.3% and wound complication rate of 0.66%. Diabetes requiring insulin and ASA Class 4 trended towards significance while renal dialysis was found to be a significant risk factors in logistic regression. This information may be useful for preoperative counseling and discussion with patients who have these risk factors.

CMC-544 (inotuzumab ozogamicin) shows less effect on multidrug resistant cells: analyses in cell lines and cells from patients with B-cell chronic lymphocytic leukaemia and lymphoma.

PubMed

Takeshita, Akihiro; Shinjo, Kaori; Yamakage, Nozomi; Ono, Takaaki; Hirano, Isao; Matsui, Hirotaka; Shigeno, Kazuyuki; Nakamura, Satoki; Tobita, Tadasu; Maekawa, Masato; Ohnishi, Kazunori; Sugimoto, Yoshikazu; Kiyoi, Hitoshi; Naoe, Tomoki; Ohno, Ryuzo

2009-06-01

The effect of CMC-544, a calicheamicin-conjugated anti-CD22 monoclonal antibody, was analysed in relation to CD22 and P-glycoprotein (P-gp) in B-cell chronic lymphocytic leukaemia (CLL) and non-Hodgkin lymphoma (NHL) in vitro. The cell lines used were CD22-positive parental Daudi and Raji, and their P-gp positive sublines, Daudi/MDR and Raji/MDR. Cells obtained from 19 patients with B-cell CLL or NHL were also used. The effect of CMC-544 was analysed by viable cell count, morphology, annexin-V staining, and cell cycle distribution. A dose-dependent, selective cytotoxic effect of CMC-544 was observed in cell lines that expressed CD22. CMC-544 was not effective on Daudi/MDR and Raji/MDR cells compared with their parental cells. The MDR modifiers, PSC833 and MS209, restored the cytotoxic effect of CMC-544 in P-gp-expressing sublines. In clinical samples, the cytotoxic effect of CMC-544 was inversely related to the amount of P-gp (P = 0.003), and to intracellular rhodamine-123 accumulation (P < 0.001). On the other hand, the effect positively correlated with the amount of CD22 (P = 0.010). The effect of CMC-544 depends on the levels of CD22 and P-gp. Our findings will help to predict the clinical effectiveness of this drug on these B-cell malignancies, suggesting a beneficial effect with combined use of CMC-544 and MDR modifiers.

CMC-Based Projects and L2 Learning: Confirming the Importance of Nativisation

ERIC Educational Resources Information Center

Grosbois, Muriel

2011-01-01

Despite the spread of reliable desktop audio and videoconferencing facilities, some CMC-based projects still rely on asynchronous written environments, if only because of the temporal constraints of synchronicity (Guichon, 2009; Develotte, Guichon & Vincent, 2010). Yet speaking is usually the skill students most need to improve when learning a…

Cohort Profile Update: The China Jintan Child Cohort Study

PubMed Central

Liu, Jianghong; Cao, Siyuan; Chen, Zehang; Raine, Adrian; Hanlon, Alexandra; Ai, Yuexian; Zhou, Guoping; Yan, Chonghuai; Leung, Patrick W; McCauley, Linda; Pinto-Martin, Jennifer

2015-01-01

The China Jintan Child Cohort study began in 2004 with 1656 pre-school participants and a research focus on studying the impact of environmental exposures, such as lead, on children’s neurobehavioural outcomes. This population cohort now includes around 1000 of the original participants, who have been assessed three times over a period of 10 years. Since the original IJE cohort profile publication in 2010, participants have experienced a critical developmental transition from pre-school to school age and then adolescence. The study has also witnessed an increase in breadth and depth of data collection from the original aim of risk assessment. This cohort has added new directions to investigate the mechanisms and protective factors for the relationship between early health factors and child physical and mental health outcomes, with an emphasis on neurobehavioural consequences. The study now encompasses 11 domains, composed of repeated measures of the original variables and new domains of biomarkers, sleep, psychophysiology, neurocognition, personality, peer relationship, mindfulness and family dynamics. Depth of evaluation has increased from parent/teacher report to self/peer report and intergenerational family report. Consequently, the cohort has additional directions to include: (i) classmates of the original cohort participants for peer relationship assessment; and (ii) parental and grandparental measures to assess personality and dynamics within families. We welcome interest in our study and ask investigators to contact the corresponding author for additional information on data acquisition. PMID:26323725

Carboxymethyl cellulose (CMC)-loaded Co-Cu doped manganese ferrite nanorods as a new dual-modal simultaneous contrast agent for magnetic resonance imaging and nanocarrier for drug delivery system

NASA Astrophysics Data System (ADS)

Abbasi Pour, Sajjad; Shaterian, Hamid Reza; Afradi, Mojgan; Yazdani-Elah-Abadi, Afshin

2017-09-01

We synthesized Co0.25Cu0.25Mn0.5Fe2O4@CMC (CCMFe2O4@CMC) nanorods as a new dual-modal simultaneous for magnetic resonance imaging contrast agent and nanocarrier for drug delivery system. Impact of CCMFe2O4@CMC nanorods were investigated on the longitudinal (T1), transverse (T2) and transverse (T2∗) relaxation times for in vitro MRI contrast agent in water and also for drug delivery system, L-dopa was coated on CCMFe2O4@CMC nanorods and then in vitro drug release test was carried out at three PHs values and different temperatures. In vitro MR imaging demonstrated that r2 value of CCMFe2O4@CMC nanorods is 138.33 mM-1 s-1, CCMFe2O4@CMC is useful as T2 contrast agent relative to other T2 contrast agants. In vitro drug release test shows the amount of released L-dopa from CCMFe2O4@CMC nanorods at medium with pH = 1.2 is more than pH = 5.3 and 7.4.

My First CMC Article Revisited: A Window on Spanish L2 Interlanguage

ERIC Educational Resources Information Center

Blake, Robert

2016-01-01

The computer-assisted language learning (CALL) field seems to change overnight with new technological affordances. Blake revisits his 2000 "LLT" article on computer-mediation communication (CMC) in order to reflect on how the field has examined this topic over the past decade or so. While the Interaction Hypothesis continues to guide…

Arthroscopic Synovectomy Combined with Autologous Fat Grafting in Early Stages of CMC Osteoarthritis of the Thumb.

PubMed

Kemper, Robert; Wirth, Johanna; Baur, Eva-Maria

2018-04-01

Background  Minimal invasive treatments such as arthroscopic techniques may be adequate to restore the anatomy and functional integrity of the thumb CMC (carpometacarpal) joint. In this paper, we reported the interposition of autologous fat tissue in combination with arthroscopic synovectomy/debridement for early stage of the thumb CMC joint osteoarthritis. Patients and Methods  Twelve patients with a mean age of 46 years with early radiological stages of thumb CMC joint osteoarthritis were included. Evaluation of outcome was measured prior and 3, 12, and 24 months after surgery including, Visual Analog Scale (VAS), QuickDASH, grip and pinch strength, range of motion (ROM), and patient satisfaction. Results  Pain at rest (or with load) was reduced from preoperative 4,7 (8,7) to 2 (5,9) at 3 to 6 months; 1,4 (4,3) at 12 months; and 0,75 (2,7) at 2 years after the surgery. Initial preoperative QuickDASH value of 52 points reduced to 33 (17-65) at 6 months, 23 (2-70) at 12 months, and 20 (11-29) at 24 months after the surgery. Grip strength and thumb pinch with respect to the contralateral untreated thumb was reduced in the first 12 months but recovered subsequently. ROM was equal to the contralateral thumb. Three patients suffered from tendinitis and required surgical treatment. One patient indicated prolonged pain symptoms. No infections were noted and no donor-site morbidity or side effects were detected. Conclusion  Arthroscopic synovectomy combined with autologous fat graft is a reliable surgical option for early thumb CMC joint osteoarthritis and that effect continues for more than 24 months.

Scanning electron microscopy (SEM) evaluation of sealing ability of MTA and EndoSequence as root-end filling materials with chitosan and carboxymethyl chitosan (CMC) as retrograde smear layer removing agents.

PubMed

Nagesh, Bolla; Jeevani, Eppala; Sujana, Varri; Damaraju, Bharagavi; Sreeha, Kaluvakolanu; Ramesh, Penumaka

2016-01-01

The purpose of this study was to evaluate the sealing ability of mineral trioxide aggregate (MTA) and EndoSequence with chitosan and carboxymethyl chitosan (CMC) as retrograde smear layer removing agents using scanning electron microscopy (SEM). Forty human single rooted teeth were taken. Crowns were decoronated and canals were obturated. Apically roots were resected and retrograde cavities were done. Based on the type of retrograde material placed and the type of smear layer removal agent used for retrograde cavities, they were divided into four groups (N = 10): Group I chitosan with EndoSequence, group II chitosan with MTA, group III CMC with EndoSequence, and Group IV CMC with MTA. All the samples were longitudinally sectioned, and the SEM analysis was done for marginal adaptation. Kruskal-Wallis and Mann-Witney analysis tests. SEM images showed the presence of less gaps in group III, i.e., CMC with EndoSequence when compared to other groups with statistically significant difference. Within the limited scope of this study, it was concluded that EndoSequence as retrograde material showed better marginal sealing ability.

How are European birth-cohort studies engaging and consulting with young cohort members?

PubMed

Lucas, Patricia J; Allnock, Debra; Jessiman, Tricia

2013-04-11

Birth cohort studies, where parents consent for their child to be enrolled in a longitudinal study prior to or soon after birth, are a powerful study design in epidemiology and developmental research. Participation often continues into adulthood. Where participants are enrolled as infants, provision should be made for consent, consultation and involvement in study design as they age. This study aims to audit and describe the extent and types of consultation and engagement currently used in birth cohorts in Europe. Seventy study groups (representing 84 cohorts) were contacted to ask about their practice in engaging and involving study members. Information was gathered from study websites and publications, 15 cohorts provided additional information via email and 17 cohorts were interviewed over the phone. The cohorts identified confirm the growth of this study design, with more than half beginning since 1990, and 4 since 2011. Most studies maintain a website open to the general public, although many are written for the scientific community only. Five studies have web pages specifically for young cohort members and one study provides a dedicated page for fathers. Cohorts send newsletters, cards, and summaries of findings to participants to stay in touch. Six cohorts use Facebook for this purpose. Five cohorts provide feedback opportunities for participants after completing a round of data collection. We know of just 8 cohorts who have a mechanism for consulting with parents and 3 a mechanism for consulting with young people themselves, although these were 'one off' consultations for some groups. Barriers to further consultation with cohort members were: concerns about impact on quality of research, ethical constraints, resource limitations, lack of importance, and previous adverse experiences. Although the children in some of the cohorts are still young (born in the last 10 years) many are old enough to include some element of consultation. Barriers to greater

Synthesis and swelling characteristics of chitosan and CMC grafted sodium acrylate-co-acrylamide using modified nanoclay and examining its efficacy for removal of dyes.

PubMed

Nagarpita, M V; Roy, Pratik; Shruthi, S B; Sailaja, R R N

2017-09-01

Chitosan/carboxy methyl chitosan (CMC) grafted sodium acrylate-co-acrylamide/nanoclay superabsorbent nanocomposites have been synthesized in this study by following conventional and microwave assisted grafting methods. Microwave assisted grafting method showed higher grafting yield with enhanced reaction rate. Effect of nanoclay on water adsorption and swelling behaviour of both the composites in acidic, neutral and alkaline medium has been studied. Results showed enhanced swelling rate and water adsorption of both composites after adding 5% of silane treated nanoclay. Dye adsorption capacity of both the composites has been investigated for crystal violet, napthol green and sunset yellow dyes. It was observed that addition of 5% nanoclay enhanced the dye adsorption in both the composites. Langmuir and Freundlich isotherm models have been used to explain the dye adsorption capabilities. The chitosan and CMC nanocomposites follow both the models with R 2 value more than 0.97. Both the composites showed enhanced dye adsorption with 5% nanoclay. Effect of pH on dye adsorption has also been studied in both the composites. Chitosan nanocomposites showed better performance in dye removal as compared to CMC nanocomposites. Copyright © 2017 Elsevier B.V. All rights reserved.

Analysis of postoperative complications associated with the use of anti-adhesion sodium hyaluronate-carboxymethylcellulose (HA-CMC) barrier after cytoreductive surgery for ovarian, fallopian tube and peritoneal cancers.

PubMed

Krill, Lauren S; Ueda, Stefanie M; Gerardi, Melissa; Bristow, Robert E

2011-02-01

To evaluate the risk of postoperative complications related to HA-CMC use in patients undergoing optimal cytoreductive surgery for primary and recurrent ovarian, fallopian tube, and peritoneal cancers. A single institution retrospective review identified all patients undergoing optimal (≤1 cm) cytoreductive surgery for primary or recurrent ovarian, fallopian tube, and peritoneal cancers between 1/95 and 12/08. Operative details and post-operative complications (<30 days) were extracted from the medical record. Fisher's exact test, Mann-Whitney-U, and multiple regression analyses were performed to identify factors, including HA-CMC use, associated with post-operative complications. Three hundred seventy-five cases were analyzed: HA-CMC was utilized in 168 debulking procedures. There was no difference in the incidence of overall morbidity for patients with HA-CMC compared to those without HA-CMC (OR 1.07; 95% CI: 0.68-1.67). On univariate analysis, application of HA-CMC increased the risk of pelvic abscess (OR 2.66; 95% CI: 1.21-5.86), particularly in the primary surgery setting (OR 4.65; 95% CI: 1.67-12.98) and in patients undergoing hysterectomy (OR 3.36; 95% CI: 1.18-9.53). After controlling for confounding factors using multiple linear regression, HA-CMC use approached statistical significance in predicting an increased risk of pelvic abscess but not major postoperative morbidity. HA-CMC adhesion barrier placement at the time of optimal cytoreductive surgery for ovarian, fallopian tube, and peritoneal cancer is not associated with major postoperative complications but may be associated with increased risk of pelvic abscess. Copyright © 2010 Elsevier Inc. All rights reserved.

Fatigue behavior of a ceramic matrix composite (CMC), 2D C{sub fiber}/SiC{sub matrix}

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

Rodrigues, P.A.; Rosa, L.G.; Steen, M.

The material described in this study is a 2D CMC of continuous carbon fibers embedded in a SiC matrix. This work presents the tensile behaviour of the material at room temperature (RT) and 1200{degrees}C. Results of uniaxial tension-tension fatigue tests carried out at both temperatures (RT and 1200{degrees}C) are also presented.

Development of a combustor liner composed of ceramic matrix composite (CMC)

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

Nishio, K.; Igashira, K.I.; Take, K.

The Research Institute of Advanced Materials Gas-Generator (AMG), which is a joint effort by the Japan Key Technology Center and 14 firms in Japan, has, since fiscal year 1992, been conducting technological studies on an innovative gas generator that will use 20% less fuel, weight 50% less, and emit 70% less NO{sub x} than the conventional gas generator through the use of advanced materials. Within this project, there is an R and D program for applying ceramic matrix composite (CMC) liners to the combustor, which is a major component of the gas generator. In the course of R and D,more » continuous SiC fiber-reinforced SiC composite (SiC{sup F}/SiC) was selected as the most suitable CMD for the combustor liner because of its thermal stability and formability. An evaluation of the applicability of the SiC{sup F}/SiC composite to the combustor liner on the basis of an evaluation of its mechanical properties and stress analysis of a SiC{sup F}/SiC combustor liner was carried out, and trial SiC{sup F}/SiC combustor liners, the largest of which was 500-mm in diameter, were fabricated by the filament winding and PIP (polymer impregnation and pyrolysis) method. Using a SiC{sup F}/SiC liner built to the actual dimensions, a noncooling combustion test was carried out and even when the gas temperature was raised to 1873K at outlet of the liner, no damage was observed after the test. Through their studies, the authors have confirmed the applicability of the selected SiC{sup F}/SiC composite as a combustor liner. In this paper, the authors describe the present state of the R and D of a CMC combustor liner.« less

Non-CMC Solutions of the Einstein Constraint Equations on Compact Manifolds with Apparent Horizon Boundaries

NASA Astrophysics Data System (ADS)

Holst, Michael; Meier, Caleb; Tsogtgerel, G.

2018-01-01

In this article we continue our effort to do a systematic development of the solution theory for conformal formulations of the Einstein constraint equations on compact manifolds with boundary. By building in a natural way on our recent work in Holst and Tsogtgerel (Class Quantum Gravity 30:205011, 2013), and Holst et al. (Phys Rev Lett 100(16):161101, 2008, Commun Math Phys 288(2):547-613, 2009), and also on the work of Maxwell (J Hyperbolic Differ Eqs 2(2):521-546, 2005a, Commun Math Phys 253(3):561-583, 2005b, Math Res Lett 16(4):627-645, 2009) and Dain (Class Quantum Gravity 21(2):555-573, 2004), under reasonable assumptions on the data we prove existence of both near- and far-from-constant mean curvature (CMC) solutions for a class of Robin boundary conditions commonly used in the literature for modeling black holes, with a third existence result for CMC appearing as a special case. Dain and Maxwell addressed initial data engineering for space-times that evolve to contain black holes, determining solutions to the conformal formulation on an asymptotically Euclidean manifold in the CMC setting, with interior boundary conditions representing excised interior black hole regions. Holst and Tsogtgerel compiled the interior boundary results covered by Dain and Maxwell, and then developed general interior conditions to model the apparent horizon boundary conditions of Dainand Maxwell for compact manifolds with boundary, and subsequently proved existence of solutions to the Lichnerowicz equation on compact manifolds with such boundary conditions. This paper picks up where Holst and Tsogtgerel left off, addressing the general non-CMC case for compact manifolds with boundary. As in our previous articles, our focus here is again on low regularity data and on the interaction between different types of boundary conditions. While our work here serves primarily to extend the solution theory for the compact with boundary case, we also develop several technical tools that have

Probabilistic Assessment of a CMC Turbine Vane

NASA Technical Reports Server (NTRS)

Murthy, Pappu L. N.; Brewer, Dave; Mital, Subodh K.

2004-01-01

In order to demonstrate the advanced CMC technology under development within the Ultra Efficient Engine Technology (UEET) program, it has been planned to fabricate, test and analyze an all CMC turbine vane made of a SiC/SiC composite material. The objective was to utilize a 5-II Satin Weave SiC/CVI SiC/ and MI SiC matrix material that was developed in-house under the Enabling Propulsion Materials (EPM) program, to design and fabricate a stator vane that can endure successfully 1000 hours of engine service conditions operation. The design requirements for the vane are to be able to withstand a maximum of 2400 F within the substrate and the hot surface temperature of 2700 F with the aid of an in-house developed Environmental/Thermal Barrier Coating (EBC/TBC) system. The vane will be tested in a High Pressure Burner Rig at NASA Glenn Research Center facility. This rig is capable of simulating the engine service environment. The present paper focuses on a probabilistic assessment of the vane. The material stress/strain relationship shows a bilinear behavior with a distinct knee corresponding to what is often termed as first matrix cracking strength. This is a critical life limiting consideration for these materials. The vane is therefore designed such that the maximum stresses are within this limit so that the structure is never subjected to loads beyond the first matrix cracking strength. Any violation of this design requirement is considered as failure. Probabilistic analysis is performed in order to determine the probability of failure based on this assumption. In the analysis, material properties, strength, and pressures are considered random variables. The variations in properties and strength are based on the actual experimental data generated in house. The mean values for the pressures on the upper surface and the lower surface are known but their distributions are unknown. In the present analysis the pressures are considered normally distributed with a nominal

Synthesis and electrospinning carboxymethyl cellulose lithium (CMC-Li) modified 9,10-anthraquinone (AQ) high-rate lithium-ion battery.

PubMed

Qiu, Lei; Shao, Ziqiang; Liu, Minglong; Wang, Jianquan; Li, Pengfa; Zhao, Ming

2014-02-15

New cellulose derivative CMC-Li was synthesized, and nanometer CMC-Li fiber was applied to lithium-ion battery and coated with AQ by electrospinning. Under the protection of inert gas, modified AQ/carbon nanofibers (CNF)/Li nanometer composite material was obtained by carbonization in 280 °C as lithium battery anode materials for the first time. The morphologies and structures performance of materials were characterized by using IR, (1)H NMR, SEM, CV and EIS, respectively. Specific capacity was increased from 197 to 226.4 mAhg(-1) after modification for the first discharge at the rate of 2C. Irreversible reduction reaction peaks of modified material appeared between 1.5 and 1.7 V and the lowest oxidation reduction peak of the difference were 0.42 V, the polarization was weaker. Performance of cell with CMC-Li with the high degree of substitution (DS) was superior to that with low DS. Cellulose materials were applied to lithium battery to improve battery performance by electrospinning. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of Dielectric Material with Ceramic Matrix Composite (CMC) Produced from Kaolinite and CaCu{sub 3}Ti{sub 4}O{sub 12} (CCTO)

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

Yin, Wong Swee; Hassan, Jumiah; Hashim, Mansor

Ceramic matrix composites (CMC) combine reinforcing ceramic phases, CaCu{sub 3}Ti{sub 4}O{sub 12} (CCTO) with a ceramic matrix, kaolinite to create materials with new and superior properties. 10% and 20% CCTO were prepared by using a conventional solid state reaction method. CMC samples were pre-sintered at 800 deg. C and sintered at 1000 deg. C. The dielectric properties of samples were measured using HP 4192A LF Impedance Analyzer. Microstructures of the samples were observed using an optical microscope. XRD was used to determine the crystalline structure of the samples. The AFM showed the morphology of the samples. The results showed thatmore » the dielectric constant and dielectric loss factor of both samples are frequency dependent. At 10 Hz, the dielectric constant is 10{sup 11} for both samples. The CMC samples were independent with temperature with low dielectric constant in the frequency range of 10{sup 4}-10{sup 6} Hz. Since the CMC samples consist of different amount of kaolinite, so each sample exhibit different defect mechanism. Different reaction may occur for different composition of material. The effects of processing conditions on the microstructure and electrical properties of CMC are also discussed.« less

Cohort profile: the Spanish WORKing life Social Security (WORKss) cohort study

PubMed Central

López Gómez, María Andrée; Durán, Xavier; Zaballa, Elena; Sanchez-Niubo, Albert; Delclos, George L; Benavides, Fernando G

2016-01-01

Purpose The global economy is changing the labour market and social protection systems in Europe. The effect of both changes on health needs to be monitored in view of an ageing population and the resulting increase in prevalence of chronic health conditions. The Spanish WORKing life Social Security (WORKss) cohort study provides unique longitudinal data to study the impact of labour trajectories and employment conditions on health, in terms of sickness absence, permanent disability and death. Participants The WORKss cohort originated from the Continuous Working Life Sample (CWLS) generated by the General Directorate for the Organization of the Social Security in Spain. The CWLS contains a 4% representative sample of all individuals in contact with the Social Security system. The WORKss cohort exclusively includes individuals with a labour trajectory from 1981 or later. In 2004, the cohort was initiated with 1 022 779 Social Security members: 840 770 (82.2%) contributors and 182 009 (17.8%) beneficiaries aged 16 and older. Findings to date The WORKss cohort includes demographic characteristics, chronological data about employment history, retirement, permanent disability and death. These data make possible the measurement of incidence of permanent disability, the number of potential years of working life lost, and the number of contracts and inactive periods with the Social Security system. The WORKss cohort was linked to temporary sickness absence registries to study medical diagnoses that lead to permanent disability and consequently to an earlier exit from the labour market in unhealthy conditions. Future plans Thanks to its administrative source, the WORKss cohort study will continue follow-up in the coming years, keeping the representativeness of the Spanish population affiliated to the Social Security system. The linkage between the WORKss cohort and temporary sickness absence registries is envisioned to continue. Future plans include the linkage of

Developing of a magnetite film of carboxymethyl cellulose grafted carboxymethyl polyvinyl alcohol (CMC-g-CMPVA) for copper removal.

PubMed

Dahlan, Nuraina Anisa; Veeramachineni, Anand Kumar; Langford, Steven James; Pushpamalar, Janarthanan

2017-10-01

Crosslinked carboxymethyl cellulose grafted carboxymethyl polyvinyl alcohol (CMC-g-CMPVA) was loaded with modified magnetite iron oxide (Fe 3 O 4 ) nanoparticles to synthesise a new and easily separable adsorbent for the removal of copper (II) ions from water. The novel adsorbents were characterised by the presence of the functional group, surface morphology, crystallinity and magnetic property. The equilibrium time from the adsorption studies was found to be less than 240min for both film and bead forms while the rate of Cu 2+ removal decreased as the initial Cu 2+ concentration increased. In addition, CMC-g-CMPVA film loaded with Fe 3 O 4 /SiO 2 nanoparticles was the best adsorbent with maximum adsorption capacity of 35.34mg/g and exhibited a reusable potential. The properties exhibited by the new heterogeneous material is a promising adsorbent for the removal and recovery of copper (II) from wastewater. Copyright © 2017 Elsevier Ltd. All rights reserved.

Potential of L-fucose isolated from Brown Seaweeds as Promising Natural Emulsifier compare to Carboxymethyl Cellulose (CMC)

NASA Astrophysics Data System (ADS)

Al-Baarri, A. N.; Legowo, A. M.; Widayat; Abduh, S. B. M.; Lestari, F. P.; Desnasari, D.; Santoso, I. P. M.

2018-02-01

L-fucose has been understood as sulfated polysaccharides and it could be extracted and fractionated from brown algae. These polysaccharides contains carbohydrate, sulfate, and protein that may be used as emulsifier. This research was aimed to study the emulsification properties of L-fucose through the determination of total dissolved solids (TDS), color CIE L*a*b* and stability of oil-in-water emulsion. As much as 0.5% of high concentrated L-fucose and 0.5% of carboxymethyl cellulose (CMC) were used as emulsifier in a 10% (v/v) oil-in-water (O/W) emulsion. The emulsifier was added to O/W emulsions and then heated at 72°C. Result of stability emulsion and TDS showed that L-fucose was comparable to the CMC but remarkable changed the color of O/W emulsion. Heating process significantly reduced the stability O/W emulsion when L-fucose was applied. As conclusion, L-fucose might be used as natural emulsifier in O/W emulsion but in the low heat treatment of food processing. This study may provide valuable information for utilizing natural emulsifier from abundant resources from nature.

Carboxymethyl Cellulose (CMC) from Oil Palm Empty Fruit Bunch (OPEFB) in the new solvent Dimethyl Sulfoxide (DMSO)/Tetrabutylammonium Fluoride (TBAF)

NASA Astrophysics Data System (ADS)

Eliza, M. Y.; Shahruddin, M.; Noormaziah, J.; Rosli, W. D. Wan

2015-06-01

The surplus of Oil Palm is the most galore wastes in Malaysia because it produced about half of the world palm oil production, which contributes a major disposal problem Synthesis from an empty fruit bunch produced products such as Carboxymethyl Cellulose (CMC), could apply in diverse application such as for paper coating, food packaging and most recently, the potential as biomaterials has been revealed. In this study, CMC was prepared by firstly dissolved the bleached pulp from OPEFB in mixture solution of dimethyl sulfoxide(DMSO)/tetrabutylammonium fluoride (TBAF) without any prior chemical modification. It took only 30 minutes to fully dissolve at temperature 60°C before sodium hydroxide (NaOH) were added for activation and monochloroacetateas terrifying agent. The final product is appeared in white powder, which is then will be analyzedby FTIR analysis. FTIR results show peaks appeared at wavenumber between 1609 cm-1 to 1614 cm-1 proved the existence of carboxymethyl groups which substitute OH groups at anhydroglucose(AGU) unit. As a conclusion, mixture solution of DMSO/TBAF is the suitable solvent used for dissolved cellulose before modifying it into CMC with higher Degree of Substitution (DS). Furthermore, the dissolution of the OPEFB bleached pulp was easy, simple and at a faster rate without prior chemical modification at temperature as low as 60°C.

CMC-coated Fe3O4 nanoparticles as new MRI probes for hepatocellular carcinoma

NASA Astrophysics Data System (ADS)

Sitthichai, Sudarat; Pilapong, Chalermchai; Thongtem, Titipun; Thongtem, Somchai

2015-11-01

Pure Fe3O4 nanoparticles and Fe3O4 magnetic nanoparticles (MNPs) coated with carboxymethyl cellulose (CMC) were successfully prepared by co-precipitating of FeCl2·4H2O and FeCl3·6H2O in the solutions containing ammonia at 80 °C for 3 h. Phase, morphology, particle-sized distribution, surface chemistry, and weight loss were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) including high-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED), thermogravimetric analysis (TGA), and Fourier transform infrared (FTIR) spectroscopy. In this research, CMC-coated Fe3O4 MNPs consisting of Fe2+ and Fe3+ ions with 543.3-mM-1 s-1 high relaxivity were detected and were able to be used for magnetic resonance imaging (MRI) application with very good contrast for targeting hepatocellular carcinoma (HCC) without any further vectorization.

Cohort profile: the Spanish WORKing life Social Security (WORKss) cohort study.

PubMed

López Gómez, María Andrée; Durán, Xavier; Zaballa, Elena; Sanchez-Niubo, Albert; Delclos, George L; Benavides, Fernando G

2016-03-07

The global economy is changing the labour market and social protection systems in Europe. The effect of both changes on health needs to be monitored in view of an ageing population and the resulting increase in prevalence of chronic health conditions. The Spanish WORKing life Social Security (WORKss) cohort study provides unique longitudinal data to study the impact of labour trajectories and employment conditions on health, in terms of sickness absence, permanent disability and death. The WORKss cohort originated from the Continuous Working Life Sample (CWLS) generated by the General Directorate for the Organization of the Social Security in Spain. The CWLS contains a 4% representative sample of all individuals in contact with the Social Security system. The WORKss cohort exclusively includes individuals with a labour trajectory from 1981 or later. In 2004, the cohort was initiated with 1,022 ,79 Social Security members: 840,770 (82.2%) contributors and 182,009 (17.8%) beneficiaries aged 16 and older. The WORKss cohort includes demographic characteristics, chronological data about employment history, retirement, permanent disability and death. These data make possible the measurement of incidence of permanent disability, the number of potential years of working life lost, and the number of contracts and inactive periods with the Social Security system. The WORKss cohort was linked to temporary sickness absence registries to study medical diagnoses that lead to permanent disability and consequently to an earlier exit from the labour market in unhealthy conditions. Thanks to its administrative source, the WORKss cohort study will continue follow-up in the coming years, keeping the representativeness of the Spanish population affiliated to the Social Security system. The linkage between the WORKss cohort and temporary sickness absence registries is envisioned to continue. Future plans include the linkage of the cohort with mortality registries. Published by the BMJ

Reliability analysis of laminated CMC components through shell subelement techniques

NASA Technical Reports Server (NTRS)

Starlinger, A.; Duffy, S. F.; Gyekenyesi, J. P.

1992-01-01

An updated version of the integrated design program C/CARES (composite ceramic analysis and reliability evaluation of structures) was developed for the reliability evaluation of CMC laminated shell components. The algorithm is now split in two modules: a finite-element data interface program and a reliability evaluation algorithm. More flexibility is achieved, allowing for easy implementation with various finite-element programs. The new interface program from the finite-element code MARC also includes the option of using hybrid laminates and allows for variations in temperature fields throughout the component.

Retention of storage quality and post-refrigeration shelf-life extension of plum (Prunus domestica L.) cv. Santa Rosa using combination of carboxymethyl cellulose (CMC) coating and gamma irradiation

NASA Astrophysics Data System (ADS)

Hussain, Peerzada R.; Suradkar, Prashant P.; Wani, Ali M.; Dar, Mohd A.

2015-02-01

Carboxymethyl cellulose (CMC) coatings alone and in combination with gamma irradiation was tested for maintaining the storage quality and extending shelf-life of plum. Matured green plums were CMC coated at levels 0.5-1.0% w/v and gamma irradiated at 1.5 kGy. The treated fruit including control was stored under ambient (temperature 25±2 °C, RH 70%) and refrigerated (temperature 3±1 °C, RH 80%) conditions. In fruits treated with individual treatments of 1.0% w/v CMC; 1.5 kGy irradiation and combination of 1.0% w/v CMC and 1.5 kGy irradiation, no decay was recorded up to 11, 17 and 21 days of ambient storage. Irradiation alone at 1.5 kGy gave 8 days extension in shelf-life of plum compared to 5 days by 1.0% w/v CMC coating following 45 days of refrigeration. All combinatory treatments of CMC coating and irradiation proved beneficial in maintaining the storage quality as well as delaying the decaying of plum during post-refrigerated storage at 25±2 °C, RH 70% but, combination of CMC at 1.0% w/v and 1.5 kGy irradiation was found significantly (p≤0.05) superior to all other treatments in maintaining the storage quality and delaying the decaying of plum. CMC coating of plums at 1.0% w/v followed by irradiation at 1.5 kGy resulted in chlorophyll retention of 19.4% after 16 days compared to 10% in control after 8 days of ambient storage. Under refrigerated conditions, same treatment gave retention of 67.6% in chlorophyll compared to 10.6% in control after 35 days of storage. The above combinatory treatment resulted in extension of 11 days in shelf-life of plum during post-refrigerated storage at 25±2 °C, RH 70% following 45 days of refrigeration. Based on microbial analysis, irradiation alone at 1.5 kGy and in combination with 1.0% w/v CMC resulted in 2.0 and 1.8 log reduction in yeast and mold count of plum fruit after 20 and 35 days of ambient and refrigerated storage, thereby ensuring consumer safety.

Limitations in the application of the Gibbs equation to anionic surfactants at the air/water surface: sodium dodecylsulfate and sodium dodecylmonooxyethylenesulfate above and below the CMC.

PubMed

Xu, Hui; Li, Pei Xun; Ma, Kun; Thomas, Robert K; Penfold, Jeffrey; Lu, Jian Ren

2013-07-30

This is a second paper responding to recent papers by Menger et al. and the ensuing discussion about the application of the Gibbs equation to surface tension (ST) data. Using new neutron reflection (NR) measurements on sodium dodecylsulfate (SDS) and sodium dodecylmonooxyethylene sulfate (SLES) above and below their CMCs and with and without added NaCl, in conjunction with the previous ST measurements on SDS by Elworthy and Mysels (EM), we conclude that (i) ST measurements are often seriously compromised by traces of divalent ions, (ii) adsorption does not generally reach saturation at the CMC, making it difficult to obtain the limiting Gibbs slope, and (iii) the significant width of micellization may make it impossible to apply the Gibbs equation in a significant range of concentration below the CMC. Menger et al. proposed ii as a reason for the difficulty of applying the Gibbs equation to ST data. Conclusions i and iii now further emphasize the failings of the ST-Gibbs analysis for determining the limiting coverage at the CMC, especially for SDS. For SDS, adsorption increases above the CMC to a value of 10 × CMC, which is about 25% greater than at the CMC and about the same as at the CMC in the presence of 0.1 M NaCl. In contrast, the adsorption of SLES reaches a limit at the CMC with no further increase up to 10 × CMC, but the addition of 0.1 M NaCl increases the surface excess by 20-25%. The results for SDS are combined with earlier NR results to generate an adsorption isotherm from 2 to 100 mM. The NR results for SDS are compared to the definitive surface tension (ST) measurements of EM, and the surface excesses agree over the range where they can safely be compared, from 2 to 6 mM. This confirms that the anomalous decrease in the slope of EM's σ - ln c curve between 6 mM and the CMC at 8.2 mM results from changes in activity associated with a significant width of micellization. This anomaly shows that it is impossible to apply the Gibbs equation usefully

Using full-cohort data in nested case-control and case-cohort studies by multiple imputation.

PubMed

Keogh, Ruth H; White, Ian R

2013-10-15

In many large prospective cohorts, expensive exposure measurements cannot be obtained for all individuals. Exposure-disease association studies are therefore often based on nested case-control or case-cohort studies in which complete information is obtained only for sampled individuals. However, in the full cohort, there may be a large amount of information on cheaply available covariates and possibly a surrogate of the main exposure(s), which typically goes unused. We view the nested case-control or case-cohort study plus the remainder of the cohort as a full-cohort study with missing data. Hence, we propose using multiple imputation (MI) to utilise information in the full cohort when data from the sub-studies are analysed. We use the fully observed data to fit the imputation models. We consider using approximate imputation models and also using rejection sampling to draw imputed values from the true distribution of the missing values given the observed data. Simulation studies show that using MI to utilise full-cohort information in the analysis of nested case-control and case-cohort studies can result in important gains in efficiency, particularly when a surrogate of the main exposure is available in the full cohort. In simulations, this method outperforms counter-matching in nested case-control studies and a weighted analysis for case-cohort studies, both of which use some full-cohort information. Approximate imputation models perform well except when there are interactions or non-linear terms in the outcome model, where imputation using rejection sampling works well. Copyright © 2013 John Wiley & Sons, Ltd.

Toward standardized reporting for a cohort study on functioning: The Swiss Spinal Cord Injury Cohort Study.

PubMed

Prodinger, Birgit; Ballert, Carolina S; Brach, Mirjam; Brinkhof, Martin W G; Cieza, Alarcos; Hug, Kerstin; Jordan, Xavier; Post, Marcel W M; Scheel-Sailer, Anke; Schubert, Martin; Tennant, Alan; Stucki, Gerold

2016-02-01

Functioning is an important outcome to measure in cohort studies. Clear and operational outcomes are needed to judge the quality of a cohort study. This paper outlines guiding principles for reporting functioning in cohort studies and addresses some outstanding issues. Principles of how to standardize reporting of data from a cohort study on functioning, by deriving scores that are most useful for further statistical analysis and reporting, are outlined. The Swiss Spinal Cord Injury Cohort Study Community Survey serves as a case in point to provide a practical application of these principles. Development of reporting scores must be conceptually coherent and metrically sound. The International Classification of Functioning, Disability and Health (ICF) can serve as the frame of reference for this, with its categories serving as reference units for reporting. To derive a score for further statistical analysis and reporting, items measuring a single latent trait must be invariant across groups. The Rasch measurement model is well suited to test these assumptions. Our approach is a valuable guide for researchers and clinicians, as it fosters comparability of data, strengthens the comprehensiveness of scope, and provides invariant, interval-scaled data for further statistical analyses of functioning.

A Study of Group Dynamics in Educational Leadership Cohort and Non-Cohort Groups

ERIC Educational Resources Information Center

Greenlee, Bobbie J.; Karanxha, Zorka

2010-01-01

The purpose of this study was to examine group dynamics of educational leadership students in cohorts and make comparisons with the group dynamics characteristics of non-cohort students. Cohorts have emerged as dynamic and adaptive entities with attendant group dynamic processes that shape collective learning and action. Cohort (n=42) and…

Screening of allergic components mediated by H(1)R in homoharringtonine injection through H(1)R/CMC-HPLC/MS.

PubMed

Guo, Ying; Han, Shengli; Cao, Jingjing; Liu, Qi; Zhang, Tao

2014-12-01

It has been reported that the histamine H1 receptor (H(1)R) gene is up-regulated in patients with allergic rhinitis and H(1)R expression level strongly correlates with the severity of allergy symptoms. Drugs for therapy should avoid allergy symptoms, especially for patients with over-expressed H(1)R. Therefore, screening of the components which could induce H(1)R activation is urgently needed for drug safety evaluation. Homoharringtonine injection is a preparation for acute nonlymphocytic leukemia, which is approved by China Food and Drug Administration (CFDA) and US Food and Drug Administration. However, severely adverse reactions often occur with intravenous injection of the preparation. In present study, an H(1)R/CMC model was applied for capturing membrane retained components which could induce H(1)R activation. Retention components were enriched and analyzed by H(1)R/CMC-HPLC/MS. Homoharringtonine was recognized, separated and identified in homoharringtonine injection. Ca(2+) flux assay and p-IP3R expression founded that homoharringtonine retained by the H1 R/CMC model increased phosphorylation of IP3R and promoted cytosolic free Ca(2+) elevation in a dose-dependent manner which further verified the activity of homoharringtonine in activating the H1 R. In conclusion, homoharringtonine was screened and identified as a potential allergic factor. This provides an indication that a patient with over-expressed H1 R should be aware of possible allergic reaction when applying homoharringtonine injection. Copyright © 2014 John Wiley & Sons, Ltd.

One-step assembly of Fe(III)-CMC chelate hydrogel onto nanoneedle-like CuO@Cu membrane with superhydrophilicity for oil-water separation

NASA Astrophysics Data System (ADS)

Dai, Jiangdong; Chang, Zhongshuai; Xie, Atian; Zhang, Ruilong; Tian, Sujun; Ge, Wenna; Yan, Yongsheng; Li, Chunxiang; Xu, Wei; Shao, Rong

2018-05-01

The research of superhydrophilic interface is developing rapidly, but the preparations of superhydrophilic surfaces through simple methods are still challenging. Herein, we reported a facile, rapid and environmentally-friendly approach for preparing a novel superhydrophilic and underwater superoleophobic membrane via the thermal oxidation of Cu mesh and one-step coordinated assembly of Fe(III)-CMC chelate hydrogel. Superhydrophilicity was attributed to the hydrophilicity of Fe(III)-CMC chelate hydrogel and nanoneedle-like rough structure of CuO@Cu membrane. The membrane was used to separate a variety of oil/water mixtures and exhibited excellent separation performance. Moreover, the membrane exhibited the excellent durability and superior stability against corrosion conditions. We envision that the Fe(III)-CMC@CuO@Cu membrane with good underwater superoleophobicity could provide a candidate not only for oil/water separation but also many other potential applications such as underwater oil manipulation, self-clean, and bio-adhesion control.

Tensile behavior of unidirectional and cross-ply CMC`s

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

Herrmann, R.K.; Kampe, S.L.

1996-12-31

The tensile behavior of two ceramic matrix composites (CMC`s) was observed. The materials of interest in this study were a glass-ceramic matrix composite (GCMC) and a Blackglas{trademark} matrix composite, both reinforced with Nicalon (SiC) fibers. Both composites were produced in laminate form with a symmetric cross-ply layup. Microstructural observations indicated the presence of significant porosity and some cracking in the Blackglas{trademark} samples, while the GCMC samples showed considerably less damage. From the observed tensile behavior of the cross-ply composites, a {open_quote}back-out{close_quote} factor for determining the unidirectional, 0{degrees} ply data of the composites was calculated using Classical Lamination Theory (CLT) andmore » compared to actual data. While the tensile properties obtained from the Blackglas{trademark} composites showed good correlation with the back-calculated values, those from the GCMC did not. Analysis indicates that the applicability of this technique is strongly influenced by the initial matrix microstructure of the composite, i.e., porosity and cracking present following processing.« less

Identifying Opportunities in the Development of Ceramic Matrix Composite (CMC) Materials for Armor Applications

DTIC Science & Technology

2017-03-01

a state of compression (Gooch 2002). At the same time research continues within the ceramics community to develop stronger and tougher ceramics...ARL-TR-7987 ● MAR 2017 US Army Research Laboratory Identifying Opportunities in the Development of Ceramic Matrix Composite (CMC...unless so designated by other authorized documents. Citation of manufacturer’s or trade names does not constitute an official endorsement or

[Application of cohort study in cancer prevention and control].

PubMed

Dai, Min; Bai, Yana; Pu, Hongquan; Cheng, Ning; Li, Haiyan; He, Jie

2016-03-01

Cancer control is a long-term work. Cancer research and intervention really need the support of cohort study. In the recent years, more and more cohort studies on cancer control were conducted in China along with the increased ability of scientific research in China. Since 2010, Cancer Hospital, Chinese Academy of Medical Sciences, collaborated with Lanzhou University and the Worker' s Hospital of Jinchuan Group Company Limited, have carried out a large-scale cohort study on cancer, which covered a population of more than 50 000 called " Jinchang cohort". Since 2012, a National Key Public Health Project, "cancer screening in urban China" , has been conducted in Jinchang, which strengthened the Jinchang cohort study. Based on the Jinchang cohort study, historical cohort study, cross-sectional study and prospective cohort study have been conducted, which would provide a lot of evidence for the cancer control in China.

The CMC/3DPNS computer program for prediction of three-dimension, subsonic, turbulent aerodynamic juncture region flow. Volume 2: Users' manual

NASA Technical Reports Server (NTRS)

Manhardt, P. D.

1982-01-01

The CMC fluid mechanics program system was developed to transmit the theoretical solution of finite element numerical solution methodology, applied to nonlinear field problems into a versatile computer code for comprehensive flow field analysis. Data procedures for the CMC 3 dimensional Parabolic Navier-Stokes (PNS) algorithm are presented. General data procedures a juncture corner flow standard test case data deck is described. A listing of the data deck and an explanation of grid generation methodology are presented. Tabulations of all commands and variables available to the user are described. These are in alphabetical order with cross reference numbers which refer to storage addresses.

Returning findings within longitudinal cohort studies: the 1958 birth cohort as an exemplar.

PubMed

Wallace, Susan E; Walker, Neil M; Elliott, Jane

2014-01-01

Population-based, prospective longitudinal cohort studies are considering the issues surrounding returning findings to individuals as a result of genomic and other medical research studies. While guidance is being developed for clinical settings, the process is less clear for those conducting longitudinal research. This paper discusses work conducted on behalf of The UK Cohort and Longitudinal Study Enhancement Resource programme (CLOSER) to examine consent requirements, process considerations and specific examples of potential findings in the context of the 1958 British Birth cohort. Beyond deciding which findings to return, there are questions of whether re-consent is needed and the possible impact on the study, how the feedback process will be managed, and what resources are needed to support that process. Recommendations are made for actions a cohort study should consider taking when making vital decisions regarding returning findings. Any decisions need to be context-specific, arrived at transparently, communicated clearly, and in the best interests of both the participants and the study.

Growth Behavior, Geometrical Shape, and Second CMC of Micelles Formed by Cationic Gemini Esterquat Surfactants.

PubMed

Bergström, L Magnus; Tehrani-Bagha, Alireza; Nagy, Gergely

2015-04-28

Micelles formed by novel gemini esterquat surfactants have been investigated with small-angle neutron scattering (SANS). The growth behavior of the micelles is found to differ conspicuously depending on the length of the gemini surfactant spacer group. The gemini surfactant with a long spacer form rather small triaxial ellipsoidal tablet-shaped micelles that grow weakly with surfactant concentration in the entire range of measured concentrations. Geminis with a short spacer, on the other hand, form weakly growing oblates or tablets at low concentrations that start to grow much more strongly into polydisperse rodlike or wormlike micelles at higher concentrations. The latter behavior is consistent with the presence of a second CMC that marks the transition from the weakly to the strongly growing regime. It is found that the growth behavior in terms of aggregation number as a function of surfactant concentration always appear concave in weakly growing regimes, while switching to convex behavior in strongly growing regimes. As a result, we are able to determine the second CMC of the geminis with short spacer by means of suggesting a rather precise definition of it, located at the point of inflection of the growth curve that corresponds to the transition from concave to convex growth behavior. Our SANS results are rationalized by comparison with the recently developed general micelle model. In particular, this theory is able to explain and reproduce the characteristic appearances of the experimental growth curves, including the presence of a second CMC and the convex strongly growing regime beyond. By means of optimizing the agreement between predictions from the general micelle model and results from SANS experiments, we are able to determine the three bending elasticity constants spontaneous curvature, bending rigidity, and saddle-splay constant for each surfactant.

Identification of novel psychoactive substances 25B-NBOMe and 4-CMC in biological material using HPLC-Q-TOF-MS and their quantification in blood using UPLC-MS/MS in case of severe intoxications.

PubMed

Wiergowski, Marek; Aszyk, Justyna; Kaliszan, Michał; Wilczewska, Kamila; Anand, Jacek Sein; Kot-Wasik, Agata; Jankowski, Zbigniew

2017-01-15

This paper describes cases of poisoning caused by new psychoactive substances such as: 25B-NBOMe (2-(4-bromo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl)methyl]ethanamine) and 4-CMC (1-(4-chlorophenyl)-2-(methylamino)-1-propanone). The analytical procedure includes rapid and selective method for the extraction and determination of 4-CMC and 25B-NBOMe in blood samples using UPLC-MS/MS technique. To the best of our knowledge, this is the first report, that involves a fully validated method for quantification of new-designer drug - 4-CMC in postmortem blood samples. The biological material was also analyzed with the use of routine analytical methods: immunochemical techniques, gas chromatography with flame ionization detection and gas chromatography with electron impact mass spectrometry. The results of real samples analyses correspond to possible toxicological effects: death resulting from 25B-NBOMe - mediated hallucinations (661ng/mL of 25B-NBOMe and 0.887ng/mL of 4-CMC), fatal overdose of 25B-NBOMe and 4-CMC (66.5ng/mL of 25B-NBOMe and 2.14ng/mL of 4-CMC) and non-fatal intoxication of these drugs (38.4ng/mL of 25B NBOMe and 0.181ng/mL of 4-CMC). Additionally, O-demethylathed O, O-bis-demethylathed and glucuronidated metabolites of 25B-NBOMe in biological specimens were detected. Copyright © 2016 Elsevier B.V. All rights reserved.

[Ethical considerations in genomic cohort study].

PubMed

Choi, Eun Kyung; Kim, Ock-Joo

2007-03-01

During the last decade, genomic cohort study has been developed in many countries by linking health data and genetic data in stored samples. Genomic cohort study is expected to find key genetic components that contribute to common diseases, thereby promising great advance in genome medicine. While many countries endeavor to build biobank systems, biobank-based genome research has raised important ethical concerns including genetic privacy, confidentiality, discrimination, and informed consent. Informed consent for biobank poses an important question: whether true informed consent is possible in population-based genomic cohort research where the nature of future studies is unforeseeable when consent is obtained. Due to the sensitive character of genetic information, protecting privacy and keeping confidentiality become important topics. To minimize ethical problems and achieve scientific goals to its maximum degree, each country strives to build population-based genomic cohort research project, by organizing public consultation, trying public and expert consensus in research, and providing safeguards to protect privacy and confidentiality.

Communication Challenges Learners Face Online: Why Addressing CMC and Language Proficiency Will Not Solve Learners' Problems

ERIC Educational Resources Information Center

Jung-Ivannikova, Liubov

2016-01-01

Computer-mediated communication (CMC) has been argued to cause (mis)communication issues. Research and practice suggest a range of tactics and strategies for educators focused on how to encourage and foster communication in a virtual learning environment (VLE) (eg, Salmon). However, while frameworks such as Salmon's support the effective…

Analysis of whisker-toughened CMC structural components using an interactive reliability model

NASA Technical Reports Server (NTRS)

Duffy, Stephen F.; Palko, Joseph L.

1992-01-01

Realizing wider utilization of ceramic matrix composites (CMC) requires the development of advanced structural analysis technologies. This article focuses on the use of interactive reliability models to predict component probability of failure. The deterministic William-Warnke failure criterion serves as theoretical basis for the reliability model presented here. The model has been implemented into a test-bed software program. This computer program has been coupled to a general-purpose finite element program. A simple structural problem is presented to illustrate the reliability model and the computer algorithm.

The Alignment of CMC Language Learning Methodologies with the Bridge21 Model of 21C Learning

ERIC Educational Resources Information Center

Bauer, Ciarán; Devitt, Ann; Tangney, Brendan

2015-01-01

This paper explores the intersection of learning methodologies to promote the development of 21st century skills with the use of Computer-Mediated Communication (CMC) tools to enhance language learning among adolescent learners. Today, technology offers a greater range of affordances in the teaching and learning of second languages while research…

Gain-of-function STAT1 mutations impair STAT3 activity in patients with chronic mucocutaneous candidiasis (CMC).

PubMed

Zheng, Jie; van de Veerdonk, Frank L; Crossland, Katherine L; Smeekens, Sanne P; Chan, Chun M; Al Shehri, Tariq; Abinun, Mario; Gennery, Andrew R; Mann, Jelena; Lendrem, Dennis W; Netea, Mihai G; Rowan, Andrew D; Lilic, Desa

2015-10-01

Signal transducer and activator of transcription 3 (STAT3) triggered production of Th-17 cytokines mediates protective immunity against fungi. Mutations affecting the STAT3/interleukin 17 (IL-17) pathway cause selective susceptibility to fungal (Candida) infections, a hallmark of chronic mucocutaneous candidiasis (CMC). In patients with autosomal dominant CMC, we and others previously reported defective Th17 responses and underlying gain-of-function (GOF) STAT1 mutations, but how this affects STAT3 function leading to decreased IL-17 is unclear. We also assessed how GOF-STAT1 mutations affect STAT3 activation, DNA binding, gene expression, cytokine production, and epigenetic modifications. We excluded impaired STAT3 phosphorylation, nuclear translocation, and sequestration of STAT3 into STAT1/STAT3 heterodimers and confirm significantly reduced transcription of STAT3-inducible genes (RORC/IL-17/IL-22/IL-10/c-Fos/SOCS3/c-Myc) as likely underlying mechanism. STAT binding to the high affinity sis-inducible element was intact but binding to an endogenous STAT3 DNA target was impaired. Reduced STAT3-dependent gene transcription was reversed by inhibiting STAT1 activation with fludarabine or enhancing histone, but not STAT1 or STAT3 acetylation with histone deacetylase (HDAC) inhibitors trichostatin A or ITF2357. Silencing HDAC1, HDAC2, and HDAC3 indicated a role for HDAC1 and 2. Reduced STAT3-dependent gene transcription underlies low Th-17 responses in GOF-STAT1 CMC, which can be reversed by inhibiting acetylation, offering novel targets for future therapies. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

REGRESSION MODELS FOR COHORT MORTALITY STUDIES

EPA Science Inventory

Cohort studies evaluate suspect health hazards from occupational or environmental exposures by recording tile facts and causes of deaths in the exposed group as they occur over an extended time period. his article reviews several methods for analyzing cohort: mortality data and s...

Thumb carpometacarpal joint congruence during functional tasks and thumb range-of-motion activities

PubMed Central

Halilaj, Eni; Moore, Douglas C; Patel, Tarpit K; Laidlaw, David H; Ladd, Amy L; Weiss, Arnold-Peter C; Crisco, Joseph J

2017-01-01

Joint incongruity is often cited as a possible etiological factor for the high incidence of thumb carpometacarpal (CMC) joint osteoarthritis (OA) in older women. There is evidence suggesting that biomechanics plays a role in CMC OA progression, but little is known about how CMC joint congruence, specifically, differs among different cohorts. The purpose of this in vivo study was to determine if CMC joint congruence differs with sex, age, and early stage OA for different thumb positions. Using CT data from 155 subjects and a congruence metric that is based on both articular morphology and joint posture, we did not find any differences in CMC joint congruence with sex or age group, but found that patients in the early stages of OA exhibit lower congruence than healthy subjects of the same age group. PMID:25570956

Thumb carpometacarpal joint congruence during functional tasks and thumb range-of-motion activities.

PubMed

Halilaj, Eni; Moore, Douglas C; Patel, Tarpit K; Laidlaw, David H; Ladd, Amy L; Weiss, Arnold-Peter C; Crisco, Joseph J

2014-01-01

Joint incongruity is often cited as a possible etiological factor for the high incidence of thumb carpometacarpal (CMC) joint osteoarthritis (OA) in older women. There is evidence suggesting that biomechanics plays a role in CMC OA progression, but little is known about how CMC joint congruence, specifically, differs among different cohorts. The purpose of this in vivo study was to determine if CMC joint congruence differs with sex, age, and early stage OA for different thumb positions. Using CT data from 155 subjects and a congruence metric that is based on both articular morphology and joint posture, we did not find any differences in CMC joint congruence with sex or age group, but found that patients in the early stages of OA exhibit lower congruence than healthy subjects of the same age group.

Development of Probabilistic Life Prediction Methodologies and Testing Strategies for MEMS and CMC's

NASA Technical Reports Server (NTRS)

Jadaan, Osama

2003-01-01

This effort is to investigate probabilistic life prediction methodologies for ceramic matrix composites and MicroElectroMechanical Systems (MEMS) and to analyze designs that determine stochastic properties of MEMS. For CMC's this includes a brief literature survey regarding lifing methodologies. Also of interest for MEMS is the design of a proper test for the Weibull size effect in thin film (bulge test) specimens. The Weibull size effect is a consequence of a stochastic strength response predicted from the Weibull distribution. Confirming that MEMS strength is controlled by the Weibull distribution will enable the development of a probabilistic design methodology for MEMS - similar to the GRC developed CARES/Life program for bulk ceramics. A main objective of this effort is to further develop and verify the ability of the Ceramics Analysis and Reliability Evaluation of Structures/Life (CARES/Life) code to predict the time-dependent reliability of MEMS structures subjected to multiple transient loads. A second set of objectives is to determine the applicability/suitability of the CARES/Life methodology for CMC analysis, what changes would be needed to the methodology and software, and if feasible, run a demonstration problem. Also important is an evaluation of CARES/Life coupled to the ANSYS Probabilistic Design System (PDS) and the potential of coupling transient reliability analysis to the ANSYS PDS.

The Hokkaido Birth Cohort Study on Environment and Children's Health: cohort profile-updated 2017.

PubMed

Kishi, Reiko; Araki, Atsuko; Minatoya, Machiko; Hanaoka, Tomoyuki; Miyashita, Chihiro; Itoh, Sachiko; Kobayashi, Sumitaka; Ait Bamai, Yu; Yamazaki, Keiko; Miura, Ryu; Tamura, Naomi; Ito, Kumiko; Goudarzi, Houman

2017-05-18

The Hokkaido Study on Environment and Children's Health is an ongoing study consisting of two birth cohorts of different population sizes: the Sapporo cohort and the Hokkaido cohort. Our primary study goals are (1) to examine the effects of low-level environmental chemical exposures on birth outcomes, including birth defects and growth retardation; (2) to follow the development of allergies, infectious diseases, and neurobehavioral developmental disorders and perform a longitudinal observation of child development; (3) to identify high-risk groups based on genetic susceptibility to environmental chemicals; and (4) to identify the additive effects of various chemicals, including tobacco smoking. The purpose of this report is to update the progress of the Hokkaido Study, to summarize the recent results, and to suggest future directions. In particular, this report provides the basic characteristics of the cohort populations, discusses the population remaining in the cohorts and those who were lost to follow-up at birth, and introduces the newly added follow-up studies and case-cohort study design. In the Sapporo cohort of 514 enrolled pregnant women, various specimens, including maternal and cord blood, maternal hair, and breast milk, were collected for the assessment of exposures to dioxins, polychlorinated biphenyls, organochlorine pesticides, perfluoroalkyl substances, phthalates, bisphenol A, and methylmercury. As follow-ups, face-to-face neurobehavioral developmental tests were conducted at several different ages. In the Hokkaido cohort of 20,926 enrolled pregnant women, the prevalence of complicated pregnancies and birth outcomes, such as miscarriage, stillbirth, low birth weight, preterm birth, and small for gestational age were examined. The levels of exposure to environmental chemicals were relatively low in these study populations compared to those reported previously. We also studied environmental chemical exposure in association with health outcomes

[Quality standards for epidemiologic cohort studies : An evaluated catalogue of requirements for the conduct and preparation of cohort studies].

PubMed

Schmidt, Carsten Oliver; Krabbe, Christine E M; Schössow, Janka; Berger, Klaus; Enzenbach, Cornelia; Kamtsiuris, Panagiotis; Schöne, Gina; Houben, Robin; Meisinger, Christa; Bamberg, Fabian; Hendel, Thomas; Selder, Sonja; Nonnemacher, Michael; Moebus, Susanne; Stausberg, Jürgen

2018-01-01

Cohort studies are a longitudinal observational study type. They are firmly established within epidemiology to assess the course of diseases and risk factors. Yet, standards to describe and evaluate quality characteristics of cohort studies need further development. Within the TMF ("Technologie- und Methodenplattform für die vernetzte medizinische Forschung e. V.") project "Quality management standards in cohort studies", a catalogue of requirements was compiled and evaluated, focusing on the preparation and conduct of epidemiologic cohort studies. The catalogue of requirements was established based on a consensus process between representatives of seven German epidemiologic cohort studies. For this purpose, a set of expert meetings (telephone, face-to-face, web-based) was conducted and the importance of each element of the catalogue was assessed as well as its implementation. A catalogue of requirements with 138 requirements was consented. It is structured into ten sections: 1. Study documentation; 2. Selection of instruments; 3. Study implementation, 4. Organizational structure; 5. Qualification and certification; 6. Participant recruitment; 7. Preparation, conduct and follow-up processing of examinations; 8. Study logistics and maintenance, 9. Data capture and data management; 10. Reporting and monitoring. In total, 41 elements were categorized as being essential, 91 as important, and 6 as less important. The catalogue of requirements provides a guideline to improve the preparation and operation of cohort studies. The evaluation of the importance and degree of implementation of requirements depended on the study design. With adaptations, the catalogue might be transferable to other study types.

Validation of the pooled cohort risk score in an Asian population - a retrospective cohort study.

PubMed

Chia, Yook Chin; Lim, Hooi Min; Ching, Siew Mooi

2014-11-20

The Pooled Cohort Risk Equation was introduced by the American College of Cardiology (ACC) and American Heart Association (AHA) 2013 in their Blood Cholesterol Guideline to estimate the 10-year atherosclerotic cardiovascular disease (ASCVD) risk. However, absence of Asian ethnicity in the contemporary cohorts and limited studies to examine the use of the risk score limit the applicability of the equation in an Asian population. This study examines the validity of the pooled cohort risk score in a primary care setting and compares the cardiovascular risk using both the pooled cohort risk score and the Framingham General Cardiovascular Disease (CVD) risk score. This is a 10-year retrospective cohort study of randomly selected patients aged 40-79 years. Baseline demographic data, co-morbidities and cardiovascular (CV) risk parameters were captured from patient records in 1998. Pooled cohort risk score and Framingham General CVD risk score for each patient were computed. All ASCVD events (nonfatal myocardial infarction, coronary heart disease (CHD) death, fatal and nonfatal stroke) occurring from 1998-2007 were recorded. A total of 922 patients were studied. In 1998, mean age was 57.5 ± 8.8 years with 66.7% female. There were 47% diabetic patients and 59.9% patients receiving anti-hypertensive treatment. More than 98% of patients with pooled cohort risk score ≥7.5% had FRS >10%. A total of 45 CVD events occurred, 22 (7.2%) in males and 23 (3.7%) in females. The median pooled cohort risk score for the population was 10.1 (IQR 4.7-20.6) while the actual ASCVD events that occurred was 4.9% (45/922). Our study showed moderate discrimination with AUC of 0.63. There was good calibration with Hosmer-Lemeshow test χ2 = 12.6, P = 0.12. The pooled cohort risk score appears to overestimate CV risk but this apparent over-prediction could be a result of treatment. In the absence of a validated score in an untreated population, the pooled cohort risk score appears to be

Ceramic Matrix Composite (CMC) Thermal Protection Systems (TPS) and Hot Structures for Hypersonic Vehicles

NASA Technical Reports Server (NTRS)

Glass, David E.

2008-01-01

Thermal protection systems (TPS) and hot structures are required for a range of hypersonic vehicles ranging from ballistic reentry to hypersonic cruise vehicles, both within Earth's atmosphere and non-Earth atmospheres. The focus of this paper is on air breathing hypersonic vehicles in the Earth's atmosphere. This includes single-stage to orbit (SSTO), two-stage to orbit (TSTO) accelerators, access to space vehicles, and hypersonic cruise vehicles. This paper will start out with a brief discussion of aerodynamic heating and thermal management techniques to address the high heating, followed by an overview of TPS for rocket-launched and air-breathing vehicles. The argument is presented that as we move from rocket-based vehicles to air-breathing vehicles, we need to move away from the insulated airplane approach used on the Space Shuttle Orbiter to a wide range of TPS and hot structure approaches. The primary portion of the paper will discuss issues and design options for CMC TPS and hot structure components, including leading edges, acreage TPS, and control surfaces. The current state-of-the-art will be briefly discussed for some of the components. The two primary technical challenges impacting the use of CMC TPS and hot structures for hypersonic vehicles are environmental durability and fabrication, and will be discussed briefly.

Establishing an Empirical Link between Computer-Mediated Communication (CMC) and SLA: A Meta-Analysis of the Research

ERIC Educational Resources Information Center

Lin, Huifen

2014-01-01

Drawing on interactionist and socio-cultural theories, tools provided in computer-mediated communication (CMC) environments have long been considered able to create an environment that shares many communicative features with face-to-face communication. Over the past two decades, researchers have employed a variety of strategies to examine the…

Global teaching and training initiatives for emerging cohort studies

PubMed Central

Paulus, Jessica K.; Santoyo-Vistrain, Rocío; Havelick, David; Cohen, Amy; Kalyesubula, Robert; Ajayi, Ikeoluwapo O.; Mattsson, Jens G.; Adami, Hans-Olov; Dalal, Shona

2015-01-01

A striking disparity exists across the globe, with essentially no large-scale longitudinal studies ongoing in regions that will be significantly affected by the oncoming non-communicable disease epidemic. The successful implementation of cohort studies in most low-resource research environments presents unique challenges that may be aided by coordinated training programs. Leaders of emerging cohort studies attending the First World Cohort Integration Workshop were surveyed about training priorities, unmet needs and potential cross-cohort solutions to these barriers through an electronic pre-workshop questionnaire and focus groups. Cohort studies representing India, Mexico, Nigeria, South Africa, Sweden, Tanzania and Uganda described similar training needs, including on-the-job training, data analysis software instruction, and database and bio-bank management. A lack of funding and protected time for training activities were commonly identified constraints. Proposed solutions include a collaborative cross-cohort teaching platform with web-based content and interactive teaching methods for a range of research personnel. An international network for research mentorship and idea exchange, and modifying the graduate thesis structure were also identified as key initiatives. Cross-cohort integrated educational initiatives will efficiently meet shared needs, catalyze the development of emerging cohorts, speed closure of the global disparity in cohort research, and may fortify scientific capacity development in low-resource settings. PMID:23856451

Thermomechanical Characterization of SiC Fiber Tows and Implications for CMC

NASA Technical Reports Server (NTRS)

Yun, H. M.; DiCarlo, J. A.

1999-01-01

In order to better understand SiC fiber behavior within CMC microstructures, mechanical tests were performed on multifilament tows consisting of different types of as produced and pretreated fibers. Tensile strengths of tows and single fibers were measured at room temperature for nonstoichiometric Hi-Nicalon and ZMI fibers and for stoichiometric Hi-Nicalon-S, Tyranno SA. and Sylramic fibers. Based on simple bundle theory, measured strengths for as-produced and sized tows were in general agreement with the single fiber results. However, after sizing removal under inert conditions, tow strengths for the coarser grained stoichiometric fibers were typically lower than those predicted from individual fiber data. This effect is attributed to enhanced fiber-fiber mechanical interaction caused by sizing removal from the rough surfaces of these fibers. In support of this, tow strengths remained high for those fiber types with fine grains or excess surface carbon; and, when re-coated with a BN interphase coating, tow strengths for the coarser grained fibers returned to their as-produced values. When the tows were pretreated in air at intermediate temperatures, tow strengths decreased in a manner that could be correlated with the oxidation characteristics of each fiber type as measured by thermogravimetric analysis. The creep and rupture properties of Hi-Nicalon and Sylramic tows were also measured in air and argon from 1200 to 1400 C. Although displaying transient and environmental effects similar to single fibers, the tows crept faster at short times and slower at long times. This resulted in the tow rupture strengths at long time being much greater than the rupture strengths of single fibers. The CMC implications of the tow results are discussed, as well as the benefits and limitations of tow testing.

Cohort studies in health sciences librarianship

PubMed Central

Eldredge, Jonathan

2002-01-01

Question: What are the key characteristics of the cohort study design and its varied applications, and how can this research design be utilized in health sciences librarianship? Data Sources: The health, social, behavioral, biological, library, earth, and management sciences literatures were used as sources. Study Selection: All fields except for health sciences librarianship were scanned topically for either well-known or diverse applications of the cohort design. The health sciences library literature available to the author principally for the years 1990 to 2000, supplemented by papers or posters presented at annual meetings of the Medical Library Association. Data Extraction: A narrative review for the health, social, behavioral, biological, earth, and management sciences literatures and a systematic review for health sciences librarianship literature for the years 1990 to 2000, with three exceptions, were conducted. The author conducted principally a manual search of the health sciences librarianship literature for the years 1990 to 2000 as part of this systematic review. Main Results: The cohort design has been applied to answer a wide array of theoretical or practical research questions in the health, social, behavioral, biological, and management sciences. Health sciences librarianship also offers several major applications of the cohort design. Conclusion: The cohort design has great potential for answering research questions in the field of health sciences librarianship, particularly evidence-based librarianship (EBL), although that potential has not been fully explored. PMID:12398244

VizieR Online Data Catalog: Carlsberg Meridian Catalog, Vol. 7 (CMC7, 1993)

NASA Astrophysics Data System (ADS)

Copenhagen University Observatory; Royal Greenwich Observatory

1995-11-01

The Carlsberg Meridian Catalogues give accurate positions, proper motions and magnitudes of stars north of declination -45deg and down to 15th magnitude. They also contain observations of the solar system objects: Mars, Callisto, Saturn, Titan, Iapetus, Uranus, Neptune, Pluto, and many minor planets. Typical mean errors for an entry are 0.1arcsec in position, 3mas/yr in proper motion, and 0.05mag in magnitude. The stars observed belong to a large number of observing programmes typically dealing with the reference frame or with galactic kinematics. The Carlsberg Automatic Meridian Circle on La Palma is operated by Copenhagen University Observatory, Royal Greenwich Observatory, and Real Instituto y Observatorio de la Armada at the Observatory del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. For a detailed introduction, please refer to the printed catalogue. A description of the programme may also be found in the 1993 paper by Fabricius (=1993BICDS..42....5F), from which the present description is derived. Originally the CMC7 was planned to contain only observations from 1991. The actual CMC7 comprises nearly 20 month (January 1991 to August 1992) and is thus more extensive than foreseen when a description was published in Bull. CDS (=1993BICDS..42....5F) Published by Copenhagen University Observatory, Royal Greenwich Observatory and Real Instituto y Observatorio de la Armada en San Fernando. 1993. (5 data files).

Integral Textile Structure for 3-D CMC Turbine Airfoils

NASA Technical Reports Server (NTRS)

Marshall, David B. (Inventor); Cox, Brian N. (Inventor); Sudre, Olivier H. (Inventor)

2017-01-01

An integral textile structure for 3-D CMC turbine airfoils includes top and bottom walls made from an angle-interlock weave, each of the walls comprising warp and weft fiber tows. The top and bottom walls are merged on a first side parallel to the warp fiber tows into a single wall along a portion of their widths, with the weft fiber tows making up the single wall interlocked through the wall's thickness such that delamination of the wall is inhibited. The single wall suitably forms the trailing edge of an airfoil; the top and bottom walls are preferably joined along a second side opposite the first side and parallel to the radial fiber tows by a continuously curved section in which the weave structure remains continuous with the weave structure in the top and bottom walls, the continuously curved section being the leading edge of the airfoil.

Life Prediction for a CMC Component Using the NASALIFE Computer Code

NASA Technical Reports Server (NTRS)

Gyekenyesi, John Z.; Murthy, Pappu L. N.; Mital, Subodh K.

2005-01-01

The computer code, NASALIFE, was used to provide estimates for life of an SiC/SiC stator vane under varying thermomechanical loading conditions. The primary intention of this effort is to show how the computer code NASALIFE can be used to provide reasonable estimates of life for practical propulsion system components made of advanced ceramic matrix composites (CMC). Simple loading conditions provided readily observable and acceptable life predictions. Varying the loading conditions such that low cycle fatigue and creep were affected independently provided expected trends in the results for life due to varying loads and life due to creep. Analysis was based on idealized empirical data for the 9/99 Melt Infiltrated SiC fiber reinforced SiC.

A rare case of idiopathic thumb CMC joint neuropathic arthropathy complicated by blunt trauma.

PubMed

Singh, Manavdeep; Butala, R R; Khedekar, R G; Tripati, Manish

2016-01-01

Neuropathic arthropathy (Charcot joints), which most frequently affects the weight-bearing joints of the body, is commonly associated with a variety of medical and neurological conditions, and is notoriously difficult to treat due to the nature of the underlying pathology. We present a case of idiopathic neuropathic arthropathy of the thumb CMC joint of an elderly female complicated by blunt trauma to the thumb. To our knowledge, this is the first reported case in the literature of this rare association.

A CMC database for use in the next generation launch vehicles (rockets)

NASA Astrophysics Data System (ADS)

Mahanta, Kamala

1994-10-01

Ceramic matrix composites (CMC's) are being envisioned as the state-of-the-art material capable of handling the tough structural and thermal demands of advanced high temperature structures for programs such as the SSTO (Single Stage to Orbit), HSCT (High Speed Civil Transport), etc. as well as for evolution of the industrial heating systems. Particulate, whisker and continuous fiber ceramic matrix (CFCC) composites have been designed to provide fracture toughness to the advanced ceramic materials which have a high degree of wear resistance, hardness, stiffness, and heat and corrosion resistance but are notorious for their brittleness and sensitivity to microscopic flaws such as cracks, voids and impurity.

A CMC database for use in the next generation launch vehicles (rockets)

NASA Technical Reports Server (NTRS)

Mahanta, Kamala

1994-01-01

Ceramic matrix composites (CMC's) are being envisioned as the state-of-the-art material capable of handling the tough structural and thermal demands of advanced high temperature structures for programs such as the SSTO (Single Stage to Orbit), HSCT (High Speed Civil Transport), etc. as well as for evolution of the industrial heating systems. Particulate, whisker and continuous fiber ceramic matrix (CFCC) composites have been designed to provide fracture toughness to the advanced ceramic materials which have a high degree of wear resistance, hardness, stiffness, and heat and corrosion resistance but are notorious for their brittleness and sensitivity to microscopic flaws such as cracks, voids and impurity.

Cohort profile: The lidA Cohort Study—a German Cohort Study on Work, Age, Health and Work Participation

PubMed Central

Hasselhorn, Hans Martin; Peter, Richard; Rauch, Angela; Schröder, Helmut; Swart, Enno; Bender, Stefan; du Prel, Jean-Baptist; Ebener, Melanie; March, Stefanie; Trappmann, Mark; Steinwede, Jacob; Müller, Bernd Hans

2014-01-01

The lidA Cohort Study (German Cohort Study on Work, Age, Health and Work Participation) was set up to investigate and follow the effects of work and work context on the physical and psychological health of the ageing workforce in Germany and subsequently on work participation. Cohort participants are initially employed people subject to social security contributions and born in either 1959 (n = 2909) or 1965 (n = 3676). They were personally interviewed in their homes in 2011 and will be visited every 3 years. Data collection comprises socio-demographic data, work and private exposures, work ability, work and work participation attitudes, health, health-related behaviour, personality and attitudinal indicators. Employment biographies are assessed using register data. Subjective health reports and physical strength measures are complemented by health insurance claims data, where permission was given. A conceptual framework has been developed for the lidA Cohort Study within which three confirmatory sub-models assess the interdependencies of work and health considering age, gender and socioeconomic status. The first set of the data will be available to the scientific community by 2015. Access will be given by the Research Data Centre of the German Federal Employment Agency at the Institute for Employment Research (http://fdz.iab.de/en.aspx). PMID:24618186

A comparison of Cox and logistic regression for use in genome-wide association studies of cohort and case-cohort design.

PubMed

Staley, James R; Jones, Edmund; Kaptoge, Stephen; Butterworth, Adam S; Sweeting, Michael J; Wood, Angela M; Howson, Joanna M M

2017-06-01

Logistic regression is often used instead of Cox regression to analyse genome-wide association studies (GWAS) of single-nucleotide polymorphisms (SNPs) and disease outcomes with cohort and case-cohort designs, as it is less computationally expensive. Although Cox and logistic regression models have been compared previously in cohort studies, this work does not completely cover the GWAS setting nor extend to the case-cohort study design. Here, we evaluated Cox and logistic regression applied to cohort and case-cohort genetic association studies using simulated data and genetic data from the EPIC-CVD study. In the cohort setting, there was a modest improvement in power to detect SNP-disease associations using Cox regression compared with logistic regression, which increased as the disease incidence increased. In contrast, logistic regression had more power than (Prentice weighted) Cox regression in the case-cohort setting. Logistic regression yielded inflated effect estimates (assuming the hazard ratio is the underlying measure of association) for both study designs, especially for SNPs with greater effect on disease. Given logistic regression is substantially more computationally efficient than Cox regression in both settings, we propose a two-step approach to GWAS in cohort and case-cohort studies. First to analyse all SNPs with logistic regression to identify associated variants below a pre-defined P-value threshold, and second to fit Cox regression (appropriately weighted in case-cohort studies) to those identified SNPs to ensure accurate estimation of association with disease.

Age, time period, and birth cohort differences in self-esteem: Reexamining a cohort-sequential longitudinal study.

PubMed

Twenge, Jean M; Carter, Nathan T; Campbell, W Keith

2017-05-01

Orth, Trzesniewski, and Robins (2010) concluded that the nationally representative Americans' Changing Lives (ACL) cohort-sequential study demonstrated moderate to large age differences in self-esteem, and no birth cohort (generational) differences in the age trajectory. In a reanalysis of these data using 2 different statistical techniques, we find significant increases in self-esteem that could be attributed to birth cohort or time period. First, hierarchical linear modeling analyses with birth cohort as a continuous variable (vs. the multiple group formulation used by Orth et al.) find that birth cohort has a measurable influence on self-esteem through its interaction with age. Participants born in later years (e.g., 1960) were higher in self-esteem and were more likely to increase in self-esteem as they aged than participants born in earlier years (e.g., 1920). However, the estimated age trajectory up to age 60 is similar in Orth et al.'s results and in the results from our analyses including cohort. Second, comparing ACL respondents of the same age in 1986 versus 2002 (a time-lag design) yields significant birth cohort differences in self-esteem, with 2002 participants of the same age higher in self-esteem than those in 1986. Combined with some previous studies finding significant increases in self-esteem and positive self-views over time, these results suggest that cultural change in the form of cohort and time period cannot be ignored as influences in cross-sectional and longitudinal studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Cultivating cohort studies for observational translational research.

PubMed

Ransohoff, David F

2013-04-01

"Discovery" research about molecular markers for diagnosis, prognosis, or prediction of response to therapy has frequently produced results that were not reproducible in subsequent studies. What are the reasons, and can observational cohorts be cultivated to provide strong and reliable answers to those questions? Experimental Selected examples are used to illustrate: (i) what features of research design provide strength and reliability in observational studies about markers of diagnosis, prognosis, and response to therapy? (ii) How can those design features be cultivated in existing observational cohorts, for example, within randomized controlled clinical trial (RCT), other existing observational research studies, or practice settings like health maintenance organization (HMOs)? Examples include a study of RNA expression profiles of tumor tissue to predict prognosis of breast cancer, a study of serum proteomics profiles to diagnose ovarian cancer, and a study of stool-based DNA assays to screen for colon cancer. Strengths and weaknesses of observational study design features are discussed, along with lessons about how features that help assure strength might be "cultivated" in the future. By considering these examples and others, it may be possible to develop a process of "cultivating cohorts" in ongoing RCTs, observational cohort studies, and practice settings like HMOs that have strong features of study design. Such an effort could produce sources of data and specimens to reliably answer questions about the use of molecular markers in diagnosis, prognosis, and response to therapy.

A Chemically Modified Curcumin (CMC 2.24) Inhibits Nuclear Factor κB Activation and Inflammatory Bone Loss in Murine Models of LPS-Induced Experimental Periodontitis and Diabetes-Associated Natural Periodontitis.

PubMed

Elburki, Muna S; Rossa, Carlos; Guimarães-Stabili, Morgana R; Lee, Hsi-Ming; Curylofo-Zotti, Fabiana A; Johnson, Francis; Golub, Lorne M

2017-08-01

The purpose of this study was to assess the effect of a novel chemically modified curcumin (CMC 2.24) on NF-κB and MAPK signaling and inflammatory cytokine production in two experimental models of periodontal disease in rats. Experimental model I: Periodontitis was induced by repeated injections of LPS into the gingiva (3×/week, 3 weeks); control rats received vehicle injections. CMC 2.24, or the vehicle, was administered by daily oral gavage for 4 weeks. Experimental model II: Diabetes was induced in adult male rats by streptozotocin injection; periodontal breakdown then results as a complication of uncontrolled hyperglycemia. Non-diabetic rats served as controls. CMC 2.24, or the vehicle, was administered by oral gavage daily for 3 weeks to the diabetics. Hemimaxillae and gingival tissues were harvested, and bone loss was assessed radiographically. Gingival tissues were pooled according to the experimental conditions and processed for the analysis of matrix metalloproteinases (MMPs) and bone-resorptive cytokines. Activation of p38 MAPK and NF-κB signaling pathways was assessed by western blot. Both LPS and diabetes induced an inflammatory process in the gingival tissues associated with excessive alveolar bone resorption and increased activation of p65 (NF-κB) and p38 MAPK. In both models, the administration of CMC 2.24 produced a marked reduction of inflammatory cytokines and MMPs in the gingival tissues, decreased bone loss, and decreased activation of p65 (NF-κB) and p38 MAPK. Inhibition of these cell signaling pathways by this novel tri-ketonic curcuminoid (natural curcumin is di-ketonic) may play a role in its therapeutic efficacy in locally and systemically associated periodontitis.

A 2 m inelastic x-ray scattering spectrometer at CMC-XOR, Advanced Photon Source.

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

Hill, J. P.; Coburn, D. S.; Kim, Y. J.

2007-07-01

The design and commissioning of an inelastic X-ray scattering instrument at CMC-XOR at the Advanced Photon Source is reported. The instrument features a 2 m vertical-scattering arm with a novel counterweight design to reduce the twisting moment as the arm is moved in the scattering plane. A Ge(733) spherical analyzer was fabricated and an overall resolution of 118 meV (FWHM) was obtained with a Si(444) monochromator and a Si(111) pre-monochromator. Early results from a representative cuprate, La{sub 2}CuO{sub 4}, are reported.

Wound Healing Studies Using Punica granatum Peel: An Animal Experimental Study.

PubMed

Zekavat, Omidreza; Amanat, Aida; Karami, Mohammadyasin; Paydar, Shahram; Gramizadeh, Bita; Zareian-Jahromi, Maryam

2016-05-01

The goal of the present study was to evaluate the effects of hydroalcoholic extract-based carboxy methyl cellulose (CMC) gel of Punica granatum peel (PCMC) and CMC on healing of full-thickness skin wounds. Forty-two rats were studied. Each rat had 3 wounds that were treated topically with PCMC as the case, CMC as the positive control, and sterile saline as the negative control. All 3 wounds of each rat were photographed during the wound healing period at days 0 (onset of wound surgery), 3, 6, 9, and 12.The wound area was calculated using Adobe Photoshop CS (version 5) software (Adobe Systems Inc, San Jose, California). Electrocardiogram paper was used for reference scale. The results of this study show that macroscopic and microscopic wound healing took a significantly longer time in wounds treated with normal saline than those treated with PCMC (grossly) and CMC gel (grossly and significantly). The authors' findings show that anti-inflammatory, antihemorrhagic, and antinecrotic effects of CMC lead to early healing of skin wounds.

Cohort profile: the Western Australian Sleep Health Study.

PubMed

Mukherjee, Sutapa; Hillman, David; Lee, Jessica; Fedson, Annette; Simpson, Laila; Ward, Kim; Love, Gregory; Edwards, Cass; Szegner, Bernadett; Palmer, Lyle John

2012-03-01

Epidemiologic and genetic studies of obstructive sleep apnoea (OSA) are limited by a lack of large-scale, well-characterized OSA cohorts. These studies require large sample size to provide adequate power to detect differences between groups. This study describes the development of such a cohort (The Western Australian Sleep Health Study) in OSA patients of Caucasian-European origin attending the only public sleep clinic in Western Australia (WA). The main aim of the study is to phenotype 4,000 OSA patients in order to define the genetics of OSA and its co-morbidities. Almost all underwent laboratory-based attended polysomnography (PSG). Currently complete data (questionnaire, biochemistry, DNA, and PSG) has been obtained on over 3,000 individuals and will reach the target of 4,000 individuals by the end of 2010. In a separate but related study, we have developed a sleep study database containing data from all patients who have undergone PSG at the sleep laboratory since its inception in 1988 until the present day (over 30,000 PSG studies representing data from approximately 20,000 individuals). In addition, data from both cohorts have been linked prospectively to statutory health data collected by the WA Department of Health. This study will be the largest sleep clinic cohort database internationally with access to genetic and epidemiological data. It is unique among sleep clinic cohorts because of its size, the breadth of data collected and the ability to link prospectively to statutory health data. It will be a major tool to comprehensively assess genetic and epidemiologic factors determining OSA and its co-morbidities.

Cohort studies in health sciences librarianship.

PubMed

Eldredge, Jonathan

2002-10-01

What are the key characteristics of the cohort study design and its varied applications, and how can this research design be utilized in health sciences librarianship? The health, social, behavioral, biological, library, earth, and management sciences literatures were used as sources. All fields except for health sciences librarianship were scanned topically for either well-known or diverse applications of the cohort design. The health sciences library literature available to the author principally for the years 1990 to 2000, supplemented by papers or posters presented at annual meetings of the Medical Library Association. A narrative review for the health, social, behavioral, biological, earth, and management sciences literatures and a systematic review for health sciences librarianship literature for the years 1990 to 2000, with three exceptions, were conducted. The author conducted principally a manual search of the health sciences librarianship literature for the years 1990 to 2000 as part of this systematic review. The cohort design has been applied to answer a wide array of theoretical or practical research questions in the health, social, behavioral, biological, and management sciences. Health sciences librarianship also offers several major applications of the cohort design. The cohort design has great potential for answering research questions in the field of health sciences librarianship, particularly evidence-based librarianship (EBL), although that potential has not been fully explored.

Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors’ Offspring

PubMed Central

Grant, Eric J; Kodama, Kazunori

2018-01-01

Cohorts of atomic bomb survivors—including those exposed in utero—and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC) in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF) in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors’ children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young. PMID:29553058

Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors' Offspring.

PubMed

Ozasa, Kotaro; Grant, Eric J; Kodama, Kazunori

2018-04-05

Cohorts of atomic bomb survivors-including those exposed in utero-and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC) in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF) in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors' children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young.

Brain-Science Based Cohort Studies

ERIC Educational Resources Information Center

Koizumi, Hideaki

2011-01-01

This article describes a number of human cohort studies based on the concept of brain-science and education. These studies assess the potential effects of new technologies on babies, children and adolescents, and test hypotheses drawn from animal and genetic case studies to see if they apply to people. A flood of information, virtual media,…

Diagnosing Meteorological Conditions Associated with Sprites and Lightning with Large Charge Moment Changes (CMC) over Oklahoma

NASA Technical Reports Server (NTRS)

Flores-Rivera, Lizxandra; Lang, Timothy J.

2014-01-01

Sprites are a category of Transient Luminous Events (TLEs) that occur in the upper atmosphere above the tops of Mesoscale Convective Systems (MCSs). They are commonly associated with lightning that produce large charge moment changes (CMCs). Synergistic use of satellite and radar-retrieved observations together with sounding data, forecasts, and lightning-detection networks allowed the diagnosis and analysis of the meteorological conditions associated with sprites as well as large-CMC lightning over Oklahoma.

Follow-up methods for retrospective cohort studies in New Zealand.

PubMed

Fawcett, Jackie; Garrett, Nick; Bates, Michael N

2002-01-01

To define a general methodology for maximising the success of follow-up processes for retrospective cohort studies in New Zealand, and to illustrate an approach to developing country-specific follow-up methodologies. We recently conducted a cohort study of mortality and cancer incidence in New Zealand professional fire fighters. A number of methods were used to trace vital status, including matching with records of the New Zealand Health Information Service (NZHIS), pension records of Work and Income New Zealand (WINZ), and electronic electoral rolls. Non-electronic methods included use of paper electoral rolls and the records of the Registrar of Births Deaths and Marriages. 95% of the theoretical person-years of follow-up of the cohort were traced using these methods. In terms of numbers of cohort members traced to end of follow-up, the most useful tracing methods were fire fighter employment records, the NZHIS, WINZ, and the electronic electoral rolls. The follow-up process used for the cohort study was highly successful. On the basis of this experience, we propose a generic, but flexible, model for follow-up of retrospective cohort studies in New Zealand. Similar models could be constructed for other countries. Successful follow-up of cohort studies is possible in New Zealand using established methods. This should encourage the use of cohort studies for the investigation of epidemiological issues. Similar models for follow-up processes could be constructed for other countries.

Case-Cohort Studies: Design and Applicability to Hand Surgery.

PubMed

Vojvodic, Miliana; Shafarenko, Mark; McCabe, Steven J

2018-04-24

Observational studies are common research strategies in hand surgery. The case-cohort design offers an efficient and resource-friendly method for risk assessment and outcomes analysis. Case-cohorts remain underrepresented in upper extremity research despite several practical and economic advantages over case-control studies. This report outlines the purpose, utility, and structure of the case-cohort design and offers a sample research question to demonstrate its value to risk estimation for adverse surgical outcomes. The application of well-designed case-cohort studies is advocated in an effort to improve the quality and quantity of observational research evidence in hand and upper extremity surgery. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Investing in Prospective Cohorts for Etiologic Study of Occupational Exposures

PubMed Central

Blair, A.; Hines, C.J.; Thomas, K.W.; Alavanja, M.C.R.; Beane Freeman, L.E.; Hoppin, J.A.; Kamel, F.; Lynch, C.F.; Lubin, J.H.; Silverman, D.T.; Whelan, E.; Zahm, S. H.; Sandler, D. P.

2015-01-01

Prospective cohorts have played a major role in understanding the contribution of diet, physical activity, medical conditions, and genes to the development of many diseases, but have not been widely used for occupational exposures. Studies in agriculture are an exception. We draw upon our experience using this design to study agricultural workers to identify conditions that might foster use of prospective cohorts to study other occupational settings. Prospective cohort studies are perceived by many as the strongest epidemiologic design. It allows updating of information on exposure and other factors, collection of biologic samples before disease diagnosis for biomarker studies, assessment of effect modification by genes, lifestyle, and other occupational exposures, and evaluation of a wide range of health outcomes. Increased use of prospective cohorts would be beneficial in identifying hazardous exposures in the workplace. Occupational epidemiologists should seek opportunities to initiate prospective cohorts to investigate high priority, occupational exposures. PMID:25603935

Interlaboratory round robin study on axial tensile properties of SiC-SiC CMC tubular test specimens [Interlaboratory round robin study on axial tensile properties of SiC/SiC tubes

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

Singh, Gyanender P.; Gonczy, Steve T.; Deck, Christian P.

An interlaboratory round robin study was conducted on the tensile strength of SiC–SiC ceramic matrix composite (CMC) tubular test specimens at room temperature with the objective of expanding the database of mechanical properties of nuclear grade SiC–SiC and establishing the precision and bias statement for standard test method ASTM C1773. The mechanical properties statistics from the round robin study and the precision statistics and precision statement are presented herein. The data show reasonable consistency across the laboratories, indicating that the current C1773–13 ASTM standard is adequate for testing ceramic fiber reinforced ceramic matrix composite tubular test specimen. Furthermore, it wasmore » found that the distribution of ultimate tensile strength data was best described with a two–parameter Weibull distribution, while a lognormal distribution provided a good description of the distribution of proportional limit stress data.« less

Interlaboratory round robin study on axial tensile properties of SiC-SiC CMC tubular test specimens [Interlaboratory round robin study on axial tensile properties of SiC/SiC tubes

DOE PAGES

Singh, Gyanender P.; Gonczy, Steve T.; Deck, Christian P.; ...

2018-04-19

An interlaboratory round robin study was conducted on the tensile strength of SiC–SiC ceramic matrix composite (CMC) tubular test specimens at room temperature with the objective of expanding the database of mechanical properties of nuclear grade SiC–SiC and establishing the precision and bias statement for standard test method ASTM C1773. The mechanical properties statistics from the round robin study and the precision statistics and precision statement are presented herein. The data show reasonable consistency across the laboratories, indicating that the current C1773–13 ASTM standard is adequate for testing ceramic fiber reinforced ceramic matrix composite tubular test specimen. Furthermore, it wasmore » found that the distribution of ultimate tensile strength data was best described with a two–parameter Weibull distribution, while a lognormal distribution provided a good description of the distribution of proportional limit stress data.« less

Feasibility of cohort studies in Estonia

PubMed Central

Innos, K.; Rahu, M.; Rahu, K.

1999-01-01

OBJECTIVES: To describe the methodology and feasibility of follow up for vital status in retrospective cohort studies in Estonia. METHODS: A cohort of 7412 workers who had been employed at two factories in Tallinn between 1946 and 1988 was followed up for vital status from the date of first employment until death, emigration, or the end of the study, 31 December 1995, whichever occurred first. The cohort was electronically linked with the National Population Registry of Estonia that was created in 1992 and includes personal identification numbers of Estonian citizens and residents, and the Mortality Database that contains information from death certificates issued in 1983-95. A manual search was carried out on several non-computerised population data sources and archives. RESULTS: By 31 December 1995, the vital status of 6780 (91.5%) subjects could be traced (4495 (60.6%) subjects were alive, 1993 (26.9%) had died, and 292 (3.9%) had emigrated). Analysis by calendar period of leaving work showed that the proportion of subjects traced was lowest in the group of workers who had left work between 1946 and 1955 (58.4%), especially those whose age at leaving work was < 30 (53.2%) or > 60 years (42.3%). Among subjects who left work in 1956-65, 1966-75, and 1976-88, the follow up rate was 84.7%, 94.6%, and 98.2%, respectively. CONCLUSIONS: The findings, which are especially important for occupational epidemiology, confirm the feasibility of conducting retrospective cohort studies in Estonia. Most of the issues discussed in the paper apply to other former Soviet countries.   PMID:10472323

The optimization of CMC concentration as graphite binder on the anode of LiFePO4 battery

NASA Astrophysics Data System (ADS)

Hidayat, S.; Cahyono, T.; Mindara, J. Y.; Riveli, N.; Alamsyah, W.; Rahayu, I.

2017-05-01

Recently, the most dominating power supply on the mobile electronics market are rechargeable Lithium-ion batteries. This is because of a higher energy density and a longer lifetime compared to similar rechargeable battery systems. Graphite is commonly used as anode material in the Lithium-ion batteries, because of its excellent electrochemical characteristics and low cost fabrication. In this paper, we reported the optimization of the concentration of the CMC (carboxymethyl cellulose), that acts as the binder for graphite anode. Based on our experimental results, the best composition of graphite : C : CMC is 90 : 8 : 2 in weight %. Anode with such composition has, based on SEM measurement, a relatively good surface morphology, while it also has relatively high conductivity, about 2.68 S/cm. The result of cyclic voltammogram with a scan rate of 10 mV/s in the voltage range of 0 to 1 Volt, shows the peak of reduction voltage at 0.85 Volts and the peak voltage of oxidation is at -1.5 Volt. The performance of the battery system with LiFePO4 set as the cathode, shows that the working voltage is about 2.67 Volts at 1 mA current-loading, with the efficiency around 47%.

Study protocol: the JEU cohort study--transversal multiaxial evaluation and 5-year follow-up of a cohort of French gamblers.

PubMed

Challet-Bouju, Gaëlle; Hardouin, Jean-Benoit; Vénisse, Jean-Luc; Romo, Lucia; Valleur, Marc; Magalon, David; Fatséas, Mélina; Chéreau-Boudet, Isabelle; Gorsane, Mohamed-Ali; Grall-Bronnec, Marie

2014-08-20

There is abundant literature on how to distinguish problem gambling (PG) from social gambling, but there are very few studies of the long-term evolution of gambling practice. As a consequence, the correlates of key state changes in the gambling trajectory are still unknown. The objective of the JEU cohort study is to identify the determinants of key state changes in the gambling practice, such as the emergence of a gambling problem, natural recovery from a gambling problem, resolution of a gambling problem with intermediate care intervention, relapses or care recourse. The present study was designed to overcome the limitations of previous cohort study on PG. Indeed, this longitudinal case-control cohort is the first which plans to recruit enough participants from different initial gambling severity levels to observe these rare changes. In particular, we plan to recruit three groups of gamblers: non-problem gamblers, problem gamblers without treatment and problem gamblers seeking treatment.Recruitment takes place in various gambling places, through the press and in care centers. Cohort participants are gamblers of both sexes who reported gambling on at least one occasion in the previous year and who were aged between 18 and 65. They were assessed through a structured clinical interview and self-assessment questionnaires at baseline and then once a year for five years. Data collection comprises sociodemographic characteristics, gambling habits (including gambling trajectory), the PG section of the DSM-IV, the South Oaks Gambling Screen, the Gambling Attitudes and Beliefs Survey - 23, the Mini International Neuropsychiatric Interview, the Wender-Utah Rating Scale-Child, the Adult ADHD Self-report Scale, somatic comorbidities (especially current treatment and Parkinson disease) and the Temperament and Character Inventory - 125. The JEU cohort study is the first study which proposes to identify the predictive factors of key state changes in gambling practice. This is

Diagnosing the Meteorological Conditions Associated with Sprites and Lightning with Large Change Moment Charges (CMC) over Oklahoma

NASA Technical Reports Server (NTRS)

Rivera Lizxandra Flores; Lang, Timothy

2013-01-01

Sprites are a category of Transient Luminous Events (TLE's) that occur in the upper atmosphere above the tops of Mesoscale Convective Systems (MCSs). They are commonly associated with lightning strokes that produce large charge moment changes (CMCs). Synergistic use of satellite and radar-retrieved observations together with sounding data, forecasts, and lightning-detection-networks allowed the diagnosis and analysis of the meteorological conditions associated with sprites as well as large-CMC lightning over Oklahoma

South Yorkshire Cohort: a 'cohort trials facility' study of health and weight - protocol for the recruitment phase.

PubMed

Relton, Clare; Bissell, Paul; Smith, Christine; Blackburn, Joanna; Cooper, Cindy L; Nicholl, Jon; Tod, Angela; Copeland, Rob; Loban, Amanda; Chater, Tim; Thomas, Kate; Young, Tracy; Weir, Carol; Harrison, Gill; Millbourn, Alison; Manners, Rachel

2011-08-11

Growing levels of both obesity and chronic disease in the general population pose a major public health problem. In the UK, an innovative 'health and weight' cohort trials facility, the 'South Yorkshire Cohort', is being built in order to provide robust evidence to inform policy, commissioning and clinical decisions in this field. This protocol reports the design of the facility and outlines the recruitment phase methods. The South Yorkshire Cohort health and weight study uses the cohort multiple randomised controlled trial design. This design recruits a large observational cohort of patients with the condition(s) of interest which then provides a facility for multiple randomised controlled trials (with large representative samples of participants, long term outcomes as standard, increased comparability between each trial conducted within the cohort and increased efficiency particularly for trials of expensive interventions) as well as ongoing information as to the natural history of the condition and treatment as usual.This study aims to recruit 20,000 participants to the population based South Yorkshire Cohort health and weight research trials facility. Participants are recruited by invitation letters from their General Practitioners. Data is collected using postal and/or online patient self completed Health Questionnaires. NHS numbers will be used to facilitate record linkage and access to routine data. Participants are eligible if they are: aged 16 - 85 years, registered with one of 40 practices in South Yorkshire, provide consent for further contact from the researchers and to have their information used to look at the benefit of health treatments. The first wave of data is being collected during 2010/12 and further waves are planned at 2 - 5 year intervals for the planned 20 year duration of the facility. The South Yorkshire Cohort combines the strengths of the standard observational, longitudinal cohort study design with a population based cohort facility

South Yorkshire Cohort: a 'cohort trials facility' study of health and weight - Protocol for the recruitment phase

PubMed Central

2011-01-01

Background Growing levels of both obesity and chronic disease in the general population pose a major public health problem. In the UK, an innovative 'health and weight' cohort trials facility, the 'South Yorkshire Cohort', is being built in order to provide robust evidence to inform policy, commissioning and clinical decisions in this field. This protocol reports the design of the facility and outlines the recruitment phase methods. Method/Design The South Yorkshire Cohort health and weight study uses the cohort multiple randomised controlled trial design. This design recruits a large observational cohort of patients with the condition(s) of interest which then provides a facility for multiple randomised controlled trials (with large representative samples of participants, long term outcomes as standard, increased comparability between each trial conducted within the cohort and increased efficiency particularly for trials of expensive interventions) as well as ongoing information as to the natural history of the condition and treatment as usual. This study aims to recruit 20,000 participants to the population based South Yorkshire Cohort health and weight research trials facility. Participants are recruited by invitation letters from their General Practitioners. Data is collected using postal and/or online patient self completed Health Questionnaires. NHS numbers will be used to facilitate record linkage and access to routine data. Participants are eligible if they are: aged 16 - 85 years, registered with one of 40 practices in South Yorkshire, provide consent for further contact from the researchers and to have their information used to look at the benefit of health treatments. The first wave of data is being collected during 2010/12 and further waves are planned at 2 - 5 year intervals for the planned 20 year duration of the facility. Discussion The South Yorkshire Cohort combines the strengths of the standard observational, longitudinal cohort study design with

Kidney stones and cardiovascular risk: a meta-analysis of cohort studies.

PubMed

Liu, Yanqiong; Li, Shan; Zeng, Zhiyu; Wang, Jian; Xie, Li; Li, Taijie; He, Yu; Qin, Xue; Zhao, Jinmin

2014-09-01

Recent epidemiologic evidence suggests an association between kidney stones and incident cardiovascular disease after adjusting for other cardiovascular risk factors, but results are inconsistent. Meta-analysis of cohort studies. Patients with kidney stones. Cohort studies with data for kidney stones and cardiovascular morbidity identified in PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and conference proceedings through February 27, 2014. Kidney stones as determined by physician diagnosis, clinical coding, or self-reported scales. Cardiovascular disease, coronary heart disease (CHD), and stroke. 6 cohort studies that contained 49,597 patients with kidney stones and 3,558,053 controls, with 133,589 cardiovascular events, were included. Pooled results suggested that kidney stones were associated with an increased adjusted risk estimate for CHD (HR, 1.19; 95% CI, 1.05-1.35; P=0.05; n=6 cohorts) and stroke (HR, 1.40; 95% CI, 1.20-1.64; P<0.001; n=3 cohorts). In particular, kidney stones conferred HRs of 1.29 (95% CI, 1.10-1.52; n=6 cohorts) and 1.31 (95% CI, 1.05-1.65; n=4 cohorts) for myocardial infarction and coronary revascularization, respectively. Moreover, the pooled female cohorts showed a statistically significant association (HR, 1.49; 95% CI, 1.21-1.82; n=4 cohorts), whereas the male cohorts showed no association (HR, 1.15; 95% CI, 0.89-1.50; n=2 cohorts). Results may be limited by substantial heterogeneity, likelihood of residual confounding, and paucity of studies that separately evaluated for effect modification by sex. Kidney stones were associated with increased cardiovascular risk, including the risk for incident CHD or stroke. There is some suggestion that the risk may be higher in women than men. Further prospective studies are needed to determine whether the association is sex specific. Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

[The design of a nationwide cohort study in Germany : the pretest studies of the German National Cohort (GNC)].

PubMed

Ahrens, W; Greiser, H; Linseisen, J; Kluttig, A; Schipf, S; Schmidt, B; Günther, K

2014-11-01

The German National Cohort (GNC) is the largest population-based cohort study in Germany. Beginning in 2014, a total of 200,000 women and men aged 20-69 years will be examined in 18 study centers. The aim of the study is to investigate the etiology of chronic diseases in relation to lifestyle, genetic, socioeconomic, and environmental factors and to develop appropriate methods for early diagnosis and prevention of diseases such as cardiovascular and respiratory diseases, cancer, diabetes, neurodegenerative/psychiatric diseases, as well as musculoskeletal and infectious diseases. Pretest studies (phase 1 and 2) were conducted to select methods, instruments, and procedures for the main study, to develop standard operating procedures, and to design and test the examination program according to acceptance, expected duration, and feasibility. The pretest studies included testing of interviews, questionnaires, anthropometric measurements, several medical examinations, and the collection of biosamples. In addition, the logistic, technical, and personnel infrastructure for the main study could be established including the study centers, the central infrastructure for data management, processes to coordinate the study, and data protection and quality management concepts. The examination program for the main phase of the GNC was designed and optimized based on the results of the pretest studies. The GNC is a population-based, highly standardized and excellently phenotyped cohort that will be the basis for new strategies for risk assessment and identification, early diagnosis, and prevention of multifactorial diseases.

The protocol of a population-based prospective cohort study in southwest of Iran to analyze common non-communicable diseases: Shahrekord cohort study.

PubMed

Khaledifar, Arsalan; Hashemzadeh, Morteza; Solati, Kamal; Poustchi, Hosseion; Bollati, Valentina; Ahmadi, Ali; Kheiri, Soleiman; Samani, Keihan Ghatreh; Banitalebi, Mehdi; Sedehi, Morteza; Malekzadeh, Reza

2018-05-25

Prospective cohort studies are considered ideal choices to study multiple outcomes and risk factors for Non-communicable diseases (NCDs). Our aim is to set-up the protocol and analyze risk factors, incidence rates, prevalence, trends, and the models of environmental and genetic determinants of NCDs and their outcomes as well as interaction among such determinants. Shahrekord cohort study (SCS) that is a population-based prospective, study on a cohort consisting of people aged 35-70 years started in November 2015 in Iran. The sample size of the original cohort is at least 10,000 people. Annual follow-ups (200,000 person-year) of the cohort were designed to be conducted up to 2036. Exposures (a detailed demographic, socioeconomic, general health, quality of life, physical activity, anthropometric indexes, stress, health literacy, social capital, nutrition and eating habits, lifestyle, occupational history, living place, blindness, deafness, electrocardiography, lung capacities, blood pressure, sleep, smoking and alcohol, contact to animals, physical examinations and medical history, dental health, used drugs and supplements, glucose and lipid profiles) were measured by relevant standard methods and questionnaires. Incidence of common NCDs (cardiovascular diseases, cancer, gastrointestinal, respiratory, renal, hepatic, accidents, injury and neurological diseases), trend of risk factors, hospitalization, disability, and death were considered the outcomes of the cohort. The definition of disease was determined based on the International Classification of Diseases 10th version (ICD-10). Routine hematologic and biochemical tests were conducted and an all-inclusive biobank (blood, hair, nail, and urine specimens) of the cohort was stored for future studies. All steps of data collection and examinations are directly monitored by the quality control team. The SCS is a unique study conducted in southwest of Iran that is a notable work given the climate conditions and

[Study of the effect of surface-active agents on living cells, used as component parts in microemulsions, based on their chemical structures and critical micelle-formative concentration (CMC)].

PubMed

Ujhelyi, Zoltán; Vecsernyés, Miklós; Bácskay, Ildikó

2013-01-01

The aim of this study was to examine the cellular effects of two nonionic amphiphilic tenside groups and their mixtures on human Caco-2 cell monolayers as dependent upon their chemical structures and physicochemical properties. The first group of polyethylene glycol esters is represented by Polysorbates and Labrasol alone and in blends, while the members of the second group:Capryol 90, Capryol PGMC, Lauroglycol 90 and Lauroglycol FCC were used as propylene glycol esters. They are increasingly used in SMEDDS as recent tensides or co-tensides to increase the solubility of hydrophobic drug. Critical micelle concentration was measured by determination of surface tension. CMC refers to the ability of solubilization of surfactants. Cytotoxicity tests were performed on Caco-2 cell monolayers by MTT and LDH methods. Caco-2 cell monolayers are convenient and reliable in vitro models of the gastrointestinal tract. Paracellular permeability was examined with Lucifer yellow assays. The integrity of cell monolayers was observed by TransEpithelial Electrical Resistance (TEER) measurements. Tight junction alterations effected by the surfactants were also characterized as evidence for paracellular pathway. Changes in sub cellular localization of the tight junction proteins: ZO-1, Claudin-land beta-cathenin, were examined by confocal laser scanning microscopy.The results of cytotoxicity assays were in agreement and showed significant differences among the cytotoxic properties of surfactants in a concentration-dependent manner. Polysorbates 20, 60, 80 are the most toxic compounds. In the case of Labrasol, the degree of esterification and lack of sorbit component decreased cytotoxicity. If the hydrophyl head was changed from polyethylene glycol to propylene glycol, the main determined factor of cytotoxicity was the monoester content and the length of carbon chain. In our CMC experiments, we found that only Labrasol showed expressed cytotoxicity above the CMC. It refers to good

Assessing the order of magnitude of outcomes in single-arm cohorts through systematic comparison with corresponding cohorts: An example from the AMOS study

PubMed Central

Hamre, Harald J; Glockmann, Anja; Tröger, Wilfried; Kienle, Gunver S; Kiene, Helmut

2008-01-01

Background When a therapy has been evaluated in the first clinical study, the outcome is often compared descriptively to outcomes in corresponding cohorts receiving other treatments. Such comparisons are often limited to selected studies, and often mix different outcomes and follow-up periods. Here we give an example of a systematic comparison to all cohorts with identical outcomes and follow-up periods. Methods The therapy to be compared (anthroposophic medicine, a complementary therapy system) had been evaluated in one single-arm cohort study: the Anthroposophic Medicine Outcomes Study (AMOS). The five largest AMOS diagnosis groups (A-cohorts: asthma, depression, low back pain, migraine, neck pain) were compared to all retrievable corresponding cohorts (C-cohorts) receiving other therapies with identical outcomes (SF-36 scales or summary measures) and identical follow-up periods (3, 6 or 12 months). Between-group differences (pre-post difference in an A-cohort minus pre-post difference in the respective C-cohort) were divided with the standard deviation (SD) of the baseline score of the A-cohort. Results A-cohorts (5 cohorts with 392 patients) were similar to C-cohorts (84 cohorts with 16,167 patients) regarding age, disease duration, baseline affection and follow-up rates. A-cohorts had ≥ 0.50 SD larger improvements than C-cohorts in 13.5% (70/517) of comparisons; improvements of the same order of magnitude (small or minimal differences: -0.49 to 0.49 SD) were found in 80.1% of comparisons; and C-cohorts had ≥ 0.50 SD larger improvements than A-cohorts in 6.4% of comparisons. Analyses stratified by diagnosis had similar results. Sensitivity analyses, restricting the comparisons to C-cohorts with similar study design (observational studies), setting (primary care) or interventions (drugs, physical therapies, mixed), or restricting comparisons to SF-36 scales with small baseline differences between A- and C-cohorts (-0.49 to 0.49 SD) also had similar results

Overview of the Japan Children’s Study 2004–2009; Cohort Study of Early Childhood Development

PubMed Central

Yamagata, Zentaro; Maeda, Tadahiko; Anme, Tokie; Sadato, Norihiro

2010-01-01

Background There are still a lot of unknown aspects about the childhood development of sociability which are based on neuroscientific basis. Purpose of the Japan Children’s Study (JCS) was to verify the normal process of child development of sociability; the trajectory and factors related development of sociability, and to collect findings and integrate the knowledge to make the plan of long-term and large scale cohort study. Methods A child cohort study underway in Japan since 2005. There are the cohort study including a infant cohort study at age of 4 months to 30 months and a preschool cohort study at age of 5 years old to 8 years old. Questionnaires, direct observation of children and cognitive testing were performed. Results In infant cohort study, 465 infants were recruited at 4 months and 367 children were followed up to 30 months, follow up rate was 78.9% and in the preschool cohort study, total 192 children (112 at 2005 and 80 at 2007) at age of 5 years old and 169 followed up to 6 years (follow up rate was 88.0%), and 79 children were followed up to 8 years old (follow up rate was 70.5%) old. Several new measurements to evaluate child sociability were developed. Some factors related to development of child sociability were found for example the ‘praise’ was related to child sociability in cohort study based on neuroscience findings. Conclusions Though the trajectory of child sociability development were not clarified, some significant factors related to development of sociability, and the basic findings to conduct a long-term and large scale cohort study were provided. PMID:20179361

Drainage Behavior in Soap Films Above and Below the CMC

NASA Astrophysics Data System (ADS)

Berg, S.; Adelizzi, E. A.; Troian, S. M.

2003-11-01

We investigate through laser interferometry the drainage behavior of Newtonian soap films initially entrained on a fiber frame at small and constant capillary number. The initial film thickness is sufficiently small that gravitational drainage is presumed minimal. The drainage of rigid soap films by capillary forces alone should proceed according to h(t) ˜ t^- 1/2. Our experimental results show much more rapid drainage with exponents as large as -2, especially for those solutions whose surfactant concentrations are below the CMC. Video recordings of the entire film surface reveal a variety of structures during the drainage process, some attributable to marginal regeneration. Though still a controversial issue, this regeneration process is believed to be caused by surfactant accumulation in the meniscus region (1). We show that modification of the relevant capillary drainage equation to account for Marangoni effects through a course-grained slip condition at the air-liquid interface produces exponents in better agreement with experimental findings. (1) V. A. Nierstrasz and G. Frens, JCIS 215, 28 (1999).

Rationale, design, and methods for Canadian alliance for healthy hearts and minds cohort study (CAHHM) - a Pan Canadian cohort study.

PubMed

Anand, Sonia S; Tu, Jack V; Awadalla, Philip; Black, Sandra; Boileau, Catherine; Busseuil, David; Desai, Dipika; Després, Jean-Pierre; de Souza, Russell J; Dummer, Trevor; Jacquemont, Sébastien; Knoppers, Bartha; Larose, Eric; Lear, Scott A; Marcotte, Francois; Moody, Alan R; Parker, Louise; Poirier, Paul; Robson, Paula J; Smith, Eric E; Spinelli, John J; Tardif, Jean-Claude; Teo, Koon K; Tusevljak, Natasa; Friedrich, Matthias G

2016-07-27

The Canadian Alliance for Healthy Hearts and Minds (CAHHM) is a pan-Canadian, prospective, multi-ethnic cohort study being conducted in Canada. The overarching objective of the CAHHM is to understand the association of socio-environmental and contextual factors (such as societal structure, activity, nutrition, social and tobacco environments, and access to health services) with cardiovascular risk factors, subclinical vascular disease, and cardiovascular and other chronic disease outcomes. Participants between 35 and 69 years of age are being recruited from existing cohorts and a new First Nations Cohort to undergo a detailed assessment of health behaviours (including diet and physical activity), cognitive function, assessment of their local home and workplace environments, and their health services access and utilization. Physical measures including weight, height, waist/hip circumference, body fat percentage, and blood pressure are collected. In addition, eligible participants undergo magnetic resonance imaging (MRI) of the brain, heart, carotid artery and abdomen to detect early subclinical vascular disease and ectopic fat deposition. CAHHM is a prospective cohort study designed to investigate the impact of community level factors, individual health behaviours, and access to health services, on cognitive function, subclinical vascular disease, fat distribution, and the development of chronic diseases among adults living in Canada.

Observational Studies: Cohort and Case-Control Studies

PubMed Central

Song, Jae W.; Chung, Kevin C.

2010-01-01

Observational studies are an important category of study designs. To address some investigative questions in plastic surgery, randomized controlled trials are not always indicated or ethical to conduct. Instead, observational studies may be the next best method to address these types of questions. Well-designed observational studies have been shown to provide results similar to randomized controlled trials, challenging the belief that observational studies are second-rate. Cohort studies and case-control studies are two primary types of observational studies that aid in evaluating associations between diseases and exposures. In this review article, we describe these study designs, methodological issues, and provide examples from the plastic surgery literature. PMID:20697313

The cmc-value of a bolalipid with two phosphocholine headgroups and a C24 alkyl chain: Unusual binding properties of fluorescence probes to bolalipid aggregates.

PubMed

Kordts, Martin; Kerth, Andreas; Drescher, Simon; Ott, Maria; Blume, Alfred

2017-09-01

Bolalipids with a long alkyl chain and two phosphocholine polar groups self-assemble in water into two different types of aggregate structures, namely helical nanofibers at low temperature and two types of micellar aggregates at higher temperature. We tried to determine the critical aggregation concentration (cac) or critical micellar concentration (cmc) of the bolalipid tetracosane-1,24-bis(phosphocholine) (PC-C24-PC) by using different fluorescent probes. The use of pyrene or pyrene derivatives as fluorophores failed, whereas the probes 1,8-ANS and particularly bis-ANS gave consistent results. The structure of the bolalipid aggregates obviously hinders partitioning or binding of pyrene derivatives into the micellar interior, whereas 1,8-ANS and bis-ANS can bind to the surface of the aggregate structures. The observed large increase in fluorescence intensity of bis-ANS indicates that binding to the hydrophobic surface of the aggregates leads to a reduction of the dye mobility. However, binding of bis-ANS is relatively weak, so that the determination of a cac/cmc-value is difficult. Simulations of the intensity curves for PC-C24-PC lead to estimates of the cac/cmc-value of 0.3-1.0×10 -6 M, depending on the structure of the aggregates. Single molecule fluorescence correlation spectroscopy was used to determine the mobility of bis-ANS as a function of concentration of PC-C24-PC. The dye diffusion time and the molecular brightness are lower at low bolalipid concentration, when only free dye is present, and increase at higher concentration when bis-ANS is bound to the aggregates. The experimental cac/cmc-values are higher than those estimated, using an incremental method for the change in Gibbs free energy for micellization with n-alkyl-phosphocholines with only one polar group as a comparison. Apparently, for PC-C24-PC in micellar or fibrous aggregates, more CH 2 groups are exposed to water than in a conventional micelle of an n-alkyl-phosphocholine. Copyright �

A clinical research analytics toolkit for cohort study.

PubMed

Yu, Yiqin; Zhu, Yu; Sun, Xingzhi; Tao, Ying; Zhang, Shuo; Xu, Linhao; Pan, Yue

2012-01-01

This paper presents a clinical informatics toolkit that can assist physicians to conduct cohort studies effectively and efficiently. The toolkit has three key features: 1) support of procedures defined in epidemiology, 2) recommendation of statistical methods in data analysis, and 3) automatic generation of research reports. On one hand, our system can help physicians control research quality by leveraging the integrated knowledge of epidemiology and medical statistics; on the other hand, it can improve productivity by reducing the complexities for physicians during their cohort studies.

Risk Factors of Clinical and Immunological Failure in South Indian Cohort on Generic Antiretroviral Therapy.

PubMed

Sadashiv, Mucheli Shravan; Rupali, Priscilla; Manesh, Abi; Kannangai, Rajesh; Abraham, Ooriapadickal Cherian; Pulimood, Susanne A; Karthik, Rajiv; Rajkumar, S; Thomas, Kurien

2017-12-01

Since the time of NACO Antiretroviral (ART) roll-out, generic ART has been the mainstay of therapy. There are many studies documenting the efficacy of generic ART but with the passage of time, failure of therapy is on the rise. As institution of second line ART has significant financial implications both for a program and for an individual it is imperative that we determine factors which contribute towards treatment failure in a cohort of patients on generic antiretroviral therapy. This was a nested matched case-control study assessing the predictors for treatment failure in our cohort who had been on Anti-retroviral therapy for at least a year. We identified 42 patients (Cases) with documented treatment failure out of our cohort of 823 patients and 42 sex, age and duration of therapy-matched controls. Using a structured proforma, we collected information from the out-patient and in-patient charts of the Infectious Diseases clinic Cohort in CMC, Vellore. A set of predetermined variables were studied as potential risk factors for treatment failure on ART. Univariate analysis showed significant association with 1) Self-reported nonadherence<95% [OR 12.81 (95%CI 1.54-281.45)]. 2) Treatment interruptions in adherent cases (OR 9.56 (95% CI 1.11-213.35)]. 3) Past inappropriate therapies [OR 9.65 (95% CI 1.12-215.94)]. 4) Diarrhoea [OR 16.40 (95% CI 2.02-3.55.960]. 5) GI opportunistic infections (OR 11.06 (95% CI 1.31 -244.27)] and 6) Drug Toxicity [OR 3.69 (95% CI 1.15-12.35).In multiple logistic regression analysis, we found independent risk factors of treatment failure to be: Self-reported non-adherence (<95%) with OR 15.46(95%CI 1.55 - 154.08), drug toxicity - OR 4.13(95%CI 1.095 - 15.534) and history of diarrhoea - OR 23.446(95%CI 2.572 - 213.70). This study reveals that besides adherence to therapy, presence of diarrhoea and occurrence of drug toxicity are significant risk factors associated with failure of anti-retroviral therapy. There is a need for further

Voluntary control of corticomuscular coherence through neurofeedback: a proof-of-principle study in healthy subjects.

PubMed

von Carlowitz-Ghori, K; Bayraktaroglu, Z; Waterstraat, G; Curio, G; Nikulin, V V

2015-04-02

Corticomuscular coherence (CMC) relates to synchronization between activity in the motor cortex and the muscle activity. The strength of CMC can be affected by motor behavior. In a proof-of-principle study, we examined whether independent of motor output parameters, healthy subjects are able to voluntarily modulate CMC in a neurofeedback paradigm. Subjects received visual online feedback of their instantaneous CMC strength, which was calculated between an optimized spatial projection of multichannel electroencephalography (EEG) and electromyography (EMG) in an individually defined target frequency range. The neurofeedback training consisted of either increasing or decreasing CMC strength using a self-chosen mental strategy while performing a simple motor task. Evaluation of instantaneous coherence showed that CMC strength was significantly larger when subjects had to increase than when to decrease CMC; this difference between the two task conditions did not depend on motor performance. The exclusion of confounding factors such as motor performance, attention and task complexity in study design provides evidence that subjects were able to voluntarily modify CMC independent of motor output parameters. Additional analysis further strengthened the assumption that the subjects' response was specifically shaped by the neurofeedback. In perspective, we suggest that CMC-based neurofeedback could provide a therapeutic approach in clinical conditions, such as motor stroke, where CMC is altered. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Systematic review of birth cohort studies in Africa

PubMed Central

Campbell, Alasdair; Rudan, Igor

2011-01-01

Aim In sub-Saharan Africa, unacceptably high rates of mortality amongst women and children continue to persist. The emergence of research employing new genomic technologies is advancing knowledge on cause of disease. This review aims to identify birth cohort studies conducted in sub-Saharan Africa and to consider their suitability as a platform to support genetic epidemiological studies. Methods A systematic literature review was conducted to identify birth cohort studies in sub-Saharan Africa across the following databases: MEDLINE, EMBASE, AFRO and OpenSIGLE. A total of 8110 papers were retrieved. Application of inclusion/exclusion criteria retained only 189 papers, of which 71 met minimum quality criteria and were retained for full text analysis. Results The search revealed 28 birth cohorts: 14 of which collected biological data, 10 collected blood samples and only one study collected DNA for storage. These studies face many methodological challenges: notably, high rates of attrition and lack of funding for several rounds of study follow up. Population-based ‘biobanks’ have emerged as a major approach to harness genomic technologies in health research and yet the sub-Saharan African region still awaits large scale birth cohort biobanks collecting DNA and associated health and lifestyle data. Conclusion Investment in this field, together with related endeavours to foster and develop research capacity for these studies, may lead to an improved understanding of the determinants of intrauterine growth and development, birth outcomes such as prematurity and low birth weight, the links between maternal and infant health, survival of infectious diseases in the first years of life, and response to vaccines and antibiotic treatment. PMID:23198102

The Netherlands Cohort Study – Meat Investigation Cohort; a population-based cohort over-represented with vegetarians, pescetarians and low meat consumers

PubMed Central

2013-01-01

Background Vegetarian diets have been associated with lower risk of chronic disease, but little is known about the health effects of low meat diets and the reliability of self-reported vegetarian status. We aimed to establish an analytical cohort over-represented with vegetarians, pescetarians and 1 day/week meat consumers, and to describe their lifestyle and dietary characteristics. In addition, we were able to compare self-reported vegetarians with vegetarians whose status has been confirmed by their response on the extensive food frequency questionnaire (FFQ). Study methods Embedded within the Netherlands Cohort Study (n = 120,852; including 1150 self-reported vegetarians), the NLCS-Meat Investigation Cohort (NLCS-MIC) was defined by combining all FFQ-confirmed-vegetarians (n = 702), pescetarians (n = 394), and 1 day/week meat consumers (n = 1,396) from the total cohort with a random sample of 2–5 days/week- and 6–7 days/week meat consumers (n = 2,965 and 5,648, respectively). Results Vegetarians, pescetarians, and 1 day/week meat consumers had more favorable dietary intakes (e.g. higher fiber/vegetables) and lifestyle characteristics (e.g. lower smoking rates) compared to regular meat consumers in both sexes. Vegetarians adhered to their diet longer than pescetarians and 1 day/week meat consumers. 75% of vegetarians with a prevalent cancer at baseline had changed to this diet after diagnosis. 50% of self-reported vegetarians reported meat or fish consumption on the FFQ. Although the misclassification that occurred in terms of diet and lifestyle when merely relying on self-reporting was relatively small, the impact on associations with disease risk remains to be studied. Conclusion We established an analytical cohort over-represented with persons at the lower end of the meat consumption spectrum which should facilitate prospective studies of major cancers and causes of death using ≥20.3 years of follow-up. PMID:24289207

Fabrication of CMC-g-PAM superporous polymer monoliths via eco-friendly Pickering-MIPEs for superior adsorption of methyl violet and methylene blue

NASA Astrophysics Data System (ADS)

Wang, Feng; Zhu, Yongfeng; Wang, Wenbo; Zong, Li; Lu, Taotao; Wang, Aiqin

2017-06-01

A series of superporous carboxymethylcellulose-graft-poly(acrylamide) (CMC-g-PAM) polymer monoliths presenting interconnected pore structure and excellent adsorption properties were prepared by one-step free-radical grafting polymerization reaction of CMC and acrylamide (AM) in the oil-in-water (O/W) Pickering-medium internal phase emulsions (Pickering-MIPEs) composed of non-toxic edible oil as a dispersion phase and natural Pal nanorods as stabilizers. The effects of Pal dosage, AM dosage, and co-surfactant Tween-20 (T-20) on the pore structures of the monoliths were studied. It was revealed that the well-defined pores were formed when the dosages of Pal and T-20 are 9-14% and 3%, respectively. The porous monolith can rapidly adsorb 1585 mg/g of methyl violet (MV) and 1625 mg/g of methylene blue (MB). After the monolith was regenerated by adsorption-desorption process for 5 times, the adsorption capacities still reached 92.1% (for MV) and 93.5% (for MB) of the initial maximum adsorption capacities. The adsorption process was fitted with Langmuir adsorption isotherm model and pseudo-second-order adsorption kinetic model very well, which indicate that mono-layer chemical adsorption mainly contribute to the high-capacity adsorption for dyes. The superporous polymer monolith prepared from eco-friendly Pickering-MIPEs shows good adsorption capacity and fast adsorption rate, which is potential adsorbent for the decontimination of dye-containing wastewater.

Cohort Profile: The JS High School study (JSHS): a cohort study of Korean adolescents.

PubMed

Choi, Dong Phil; Lee, Joo Young; Kim, Hyeon Chang

2017-04-01

Major aetiologies of atherosclerotic cardiovascular diseases begin in childhood and atherosclerotic vascular abnormalities can be observed among children and adolescents. Adolescent cohort studies have important advantages because they can observe earlier changes in vascular structure and function. The purpose of the JS High School study (JSHS) is to identify biomarkers predicting or indicating early structural and functional vascular change in adolescents. The JSHS is a prospective cohort study of a Korean adolescent population. The target population of the JSHS was first-graders (aged 14 to17 years) at a high school of South Korea. Enrolment and baseline examinations were conducted in years 2007, 2010, 2011 and 2012. Among the total eligible population of 1115 students, 1071 (96.1%) participated in the study and completed all baseline examinations. Informed consent forms were obtained from each participant and his/her parent or guardian. Baseline examinations include: questionnaires on demographics, health behaviours, medical history, and depression symptoms; fasting blood analysis; anthropometric measurement; body impedance analysis; blood pressure measurement; radial artery tonometry; bone densitometry; pulmonary function tests; and carotid ultrasonography. Participants enrolled from 2007 through 2012 were re-examined after 30 months of follow-up, and those who enrolled in 2012 were re-examined after 24 months of follow-up. The corresponding author may be contacted for potential collaboration and data access. © The Author 2015; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Cardiovascular Disease Risk in NASA Astronauts Across the Lifespan: Historical Cohort Studies

NASA Technical Reports Server (NTRS)

Charvat, Jacqueline M.; Lee, Stuart M. C.; Davenport, Eddie; Barlow, Carolyn E.; Radford, Nina B.; De Fina, Laura F.; Stenger, Michael B.; Van Baalen, Mary

2017-01-01

Acute effects of spaceflight on the cardiovascular system have been studied extensively, but the combined chronic effects of spaceflight and aging are not well understood. Preparation for and participation in space flight activities are potentially associated with cardiovascular disease risk factors (e.g., altered dietary and exercise habits, physical and emotional stress, circadian shifts, radiation). Further, astronauts who travel into space multiple times may be at an increased risk across their lifespan. However, comparing the risk of cardiovascular disease in astronauts to other large cohorts is difficult. For example, comparisons between astronauts and large national cohorts, such as the National Health and Nutrition Examination Survey and the National Health Information Survey, are hampered by significant differences in health status between astronauts and the general population, and most of these national studies fail to provide longitudinal data on population health. To address those limitations, NASA's Longitudinal Study of Astronaut Health previously sought to compare the astronauts to a cohort of civil servants employed at the Johnson Space Center. However, differences between the astronauts and civil servants at the beginning of the study, as well as differential follow up, limited the ability to interpret the results. To resolve some of these limitations, two unique cohorts of healthy workers, U.S. Air Force aviators and Cooper Center Longitudinal Study participants, have been identified as potential comparison populations for the astronaut corps. The Air Force cohort was chosen due to similarities in health at selection, screening, and some occupational exposures that Air Force aviators endure, many of which mirror that of the astronaut corps. The Cooper Clinic cohort, a generally healthy prevention cohort, was chosen for the vast array of clinical cardiovascular measures collected in a longitudinal manner complementary to those collected on

Cohort Differences in Cognitive Aging in the Longitudinal Aging Study Amsterdam.

PubMed

Brailean, Anamaria; Huisman, Martijn; Prince, Martin; Prina, A Matthew; Deeg, Dorly J H; Comijs, Hannie

2016-09-30

This study aims to examine cohort differences in cognitive performance and rates of change in episodic memory, processing speed, inductive reasoning, and general cognitive performance and to investigate whether these cohort effects may be accounted for by education attainment. The first cohort (N = 705) was born between 1920 and 1930, whereas the second cohort (N = 646) was born between 1931 and 1941. Both birth cohorts were aged 65 to 75 years at baseline and were followed up 3 and 6 years later. Data were analyzed using linear mixed models. The later born cohort had better general cognitive performance, inductive reasoning, and processing speed at baseline, but cohort differences in inductive reasoning and general cognitive performance disappeared after adjusting for education. The later born cohort showed steeper decline in processing speed. Memory decline was steeper in the earlier born cohort but only from Time 1 to Time 3 when the same memory test was administered. Education did not account for cohort differences in cognitive decline. The later born cohort showed better initial performance in certain cognitive abilities, but no better preservation of cognitive abilities overtime compared with the earlier born cohort. These findings carry implications for healthy cognitive aging. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America.

Cohort profile: The Canadian HIV Women's Sexual and Reproductive Health Cohort Study (CHIWOS).

PubMed

Loutfy, Mona; de Pokomandy, Alexandra; Kennedy, V Logan; Carter, Allison; O'Brien, Nadia; Proulx-Boucher, Karène; Ding, Erin; Lewis, Johanna; Nicholson, Valerie; Beaver, Kerrigan; Greene, Saara; Tharao, Wangari; Benoit, Anita; Dubuc, Danièle; Thomas-Pavanel, Jamie; Sereda, Paul; Jabbari, Shahab; Shurgold, Jayson H; Colley, Guillaume; Hogg, Robert S; Kaida, Angela

2017-01-01

Globally, women are at increased vulnerability to HIV due to biological, social, structural, and political reasons. Women living with HIV also experience unique issues related to their medical and social healthcare, which makes a clinical care model specific to their needs worthy of exploration. Furthermore, there is a dearth of research specific to women living with HIV. Research for this population has often been narrowly focused on pregnancy-related issues without considering their complex structural inequalities, social roles, and healthcare and biological needs. For these reasons, we have come together, as researchers, clinicians and community members in Canada, to develop the Canadian HIV Women's Sexual and Reproductive Health Cohort Study (CHIWOS) to investigate the concept of women-centred HIV care (WCHC) and its impact on the overall, HIV, women's, mental, sexual, and reproductive health outcomes of women living with HIV. Here, we present the CHIWOS cohort profile, which describes the cohort and presents preliminary findings related to perceived WCHC. CHIWOS is a prospective, observational cohort study of women living with HIV in British Columbia (BC), Ontario, and Quebec. Two additional Canadian provinces, Saskatchewan and Manitoba, will join the cohort in 2018. Using community-based research principles, CHIWOS engages women living with HIV throughout the entire research process meeting the requirements of the 'Greater Involvement of People living with HIV/AIDS'. Study data are collected through an interviewer-administered questionnaire that uses a web-based platform. From August 2013 to May 2015, a total of 1422 women living with HIV in BC, Ontario, and Quebec were enrolled and completed the baseline visit. Follow-up interviews are being conducted at 18-month intervals. Of the 1422 participants at baseline, 356 were from BC (25%), 713 from Ontario (50%), 353 from Quebec (25%). The median age of the participants at baseline was 43 years (range, 16-74). 22

Health Impact of US Military Service in a Large Population-Based Military Cohort: Findings of the Millennium Cohort Study, 2001-2008

DTIC Science & Technology

2011-01-01

427. 26. Smith TC, Wingard DL, Ryan MA, Kritz- Silverstein D, Slymen DJ, Sallis JF, for the Millennium Cohort Study Team: Prior assault and... Silverstein D, for the Millennium Cohort Study Team: New onset and persistent symptoms of post- traumatic stress disorder self reported after deployment...deployed to the 2003 Iraq war: a cohort study. Lancet 2006, 367(9524):1731-1741. 41. Smith TC, Wingard DL, Ryan MAK, Kritz- Silverstein D, Slymen DJ, Sallis

Statistical Analysis of CMC Constituent and Processing Data

NASA Technical Reports Server (NTRS)

Fornuff, Jonathan

2004-01-01

Ceramic Matrix Composites (CMCs) are the next "big thing" in high-temperature structural materials. In the case of jet engines, it is widely believed that the metallic superalloys currently being utilized for hot structures (combustors, shrouds, turbine vanes and blades) are nearing their potential limits of improvement. In order to allow for increased turbine temperatures to increase engine efficiency, material scientists have begun looking toward advanced CMCs and SiC/SiC composites in particular. Ceramic composites provide greater strength-to-weight ratios at higher temperatures than metallic alloys, but at the same time require greater challenges in micro-structural optimization that in turn increases the cost of the material as well as increases the risk of variability in the material s thermo-structural behavior. to model various potential CMC engine materials and examines the current variability in these properties due to variability in component processing conditions and constituent materials; then, to see how processing and constituent variations effect key strength, stiffness, and thermal properties of the finished components. Basically, this means trying to model variations in the component s behavior by knowing what went into creating it. inter-phase and manufactured by chemical vapor infiltration (CVI) and melt infiltration (MI) were considered. Examinations of: (1) the percent constituents by volume, (2) the inter-phase thickness, (3) variations in the total porosity, and (4) variations in the chemical composition of the Sic fiber are carried out and modeled using various codes used here at NASA-Glenn (PCGina, NASALife, CEMCAN, etc...). The effects of these variations and the ranking of their respective influences on the various thermo-mechanical material properties are studied and compared to available test data. The properties of the materials as well as minor changes to geometry are then made to the computer model and the detrimental effects

Prostate Cancer Stem Cell-Targeted Efficacy of a New-Generation Taxoid, SBT-1214 and Novel Polyenolic Zinc-Binding Curcuminoid, CMC2.24

PubMed Central

Botchkina, Galina I.; Zuniga, Edison S.; Rowehl, Rebecca H.; Park, Rosa; Bhalla, Rahuldev; Bialkowska, Agnieszka B.; Johnson, Francis; Golub, Lorne M.; Zhang, Yu; Ojima, Iwao; Shroyer, Kenneth R.

2013-01-01

Background Prostate cancer is the second leading cause of cancer death among men. Multiple evidence suggests that a population of tumor-initiating, or cancer stem cells (CSCs) is responsible for cancer development and exceptional drug resistance, representing a highly important therapeutic target. The present study evaluated CSC-specific alterations induced by new-generation taxoid SBT-1214 and a novel polyenolic zinc-binding curcuminoid, CMC2.24, in prostate CSCs. Principal Findings The CD133high/CD44high phenotype was isolated from spontaneously immortalized patient-derived PPT2 cells and highly metastatic PC3MM2 cells. Weekly treatment of the NOD/SCID mice bearing PPT2- and PC3MM3-induced tumors with the SBT-1214 led to dramatic suppression of tumor growth. Four of six PPT2 and 3 of 6 PC3MM2 tumors have shown the absence of viable cells in residual tumors. In vitro, SBT-1214 (100nM-1µM; for 72 hr) induced about 60% cell death in CD133high/CD44+/high cells cultured on collagen I in stem cell medium (in contrast, the same doses of paclitaxel increased proliferation of these cells). The cytotoxic effects were increased when SBT-1214 was combined with the CMC2.24. A stem cell-specific PCR array assay revealed that this drug combination mediated massive inhibition of multiple constitutively up-regulated stem cell-related genes, including key pluripotency transcription factors. Importantly, this drug combination induced expression of p21 and p53, which were absent in CD133high/CD44high cells. Viable cells that survived this treatment regimen were no longer able to induce secondary spheroids, exhibited significant morphological abnormalities and died in 2-5 days. Conclusions We report here that the SBT-1214 alone, or in combination with CMC2.24, possesses significant activity against prostate CD133high/CD44+/high tumor-initiating cells. This drug combination efficiently inhibits expression of the majority of stem cell-related genes and pluripotency transcription

Multiple imputation of missing data in nested case-control and case-cohort studies.

PubMed

Keogh, Ruth H; Seaman, Shaun R; Bartlett, Jonathan W; Wood, Angela M

2018-06-05

The nested case-control and case-cohort designs are two main approaches for carrying out a substudy within a prospective cohort. This article adapts multiple imputation (MI) methods for handling missing covariates in full-cohort studies for nested case-control and case-cohort studies. We consider data missing by design and data missing by chance. MI analyses that make use of full-cohort data and MI analyses based on substudy data only are described, alongside an intermediate approach in which the imputation uses full-cohort data but the analysis uses only the substudy. We describe adaptations to two imputation methods: the approximate method (MI-approx) of White and Royston () and the "substantive model compatible" (MI-SMC) method of Bartlett et al. (). We also apply the "MI matched set" approach of Seaman and Keogh () to nested case-control studies, which does not require any full-cohort information. The methods are investigated using simulation studies and all perform well when their assumptions hold. Substantial gains in efficiency can be made by imputing data missing by design using the full-cohort approach or by imputing data missing by chance in analyses using the substudy only. The intermediate approach brings greater gains in efficiency relative to the substudy approach and is more robust to imputation model misspecification than the full-cohort approach. The methods are illustrated using the ARIC Study cohort. Supplementary Materials provide R and Stata code. © 2018, The International Biometric Society.

The Chinese Children and Families Cohort Study

PubMed Central

Potischman, Nancy; Fang, Liwen; Hao, Ling; Bailey, Regan R.; Berrigan, David; Berry, Robert John; Brodie, Alison; Chao, Ann; Chen, Jing; Dodd, Kevin; Feng, Yajing; Ma, Guansheng; He, Yuna; Fan, Jing; Kimlin, Michael; Kitahara, Cari; Linet, Martha; Li, Zhu; Liu, Ailing; Liu, Yashan; Sampson, Joshua; Su, Joseph; Sun, Jiandong; Tasevska, Natasha; Yang, Lichen; Yang, Ruilan; Zhang, Qian; Wang, Ning; Wang, Linhong; Yu, Wang

2018-01-01

This article reports the study design, methodological issues and early results of a pilot study testing methods for collecting nutrition, physical activity, and ultraviolet (UV) radiation exposure data in a groundbreaking study in China. Epidemiological studies suggest that exposures across the entire life course, including in utero, early childhood, and adolescence, may be important in the etiology of adult cancers and other chronic diseases. The Chinese Children and Families Cohort Study intends to follow-up subjects from the 1993 to 1995 Community Intervention Program of folic acid supplementation for the prevention of neural tube defects. This cohort is unique in that only folic acid exposure during pregnancy varies between groups as other supplements were not available, and there were nutrient deficiencies in the populations. Prior to launching a large-scale follow-up effort, a pilot study was conducted to assess the feasibility of recontacting original study participants to collect extensive diet, physical activity, and UV radiation exposure data in this population. The pilot study included 92 mothers and 184 adolescent children aged 14 to 17 years from 1 urban and 1 rural Community Intervention Program site. Subjects completed a Food Frequency Questionnaire, a 3-day food record, a physical activity questionnaire, a 3-day sun exposure diary together with 3 days of personal UV dosimetry, and 7 days of pedometry measurements and provided blood, saliva, and toenail samples. Grip strength and body composition measurements were taken, and ambient solar UV radiation was monitored in both study sites. While most of the assessments were successful, future studies would likely require different dietary intake instruments. The purpose of this report is to describe the study design and methodological issues emerging from this pilot work relevant for the follow-up of this large birth cohort. PMID:29930434

Reliability analysis of laminated CMC components through shell subelement techniques

NASA Technical Reports Server (NTRS)

Starlinger, Alois; Duffy, Stephen F.; Gyekenyesi, John P.

1992-01-01

An updated version of the integrated design program Composite Ceramics Analysis and Reliability Evaluation of Structures (C/CARES) was developed for the reliability evaluation of ceramic matrix composites (CMC) laminated shell components. The algorithm is now split into two modules: a finite-element data interface program and a reliability evaluation algorithm. More flexibility is achieved, allowing for easy implementation with various finite-element programs. The interface program creates a neutral data base which is then read by the reliability module. This neutral data base concept allows easy data transfer between different computer systems. The new interface program from the finite-element code Matrix Automated Reduction and Coupling (MARC) also includes the option of using hybrid laminates (a combination of plies of different materials or different layups) and allows for variations in temperature fields throughout the component. In the current version of C/CARES, a subelement technique was implemented, enabling stress gradients within an element to be taken into account. The noninteractive reliability function is now evaluated at each Gaussian integration point instead of using averaging techniques. As a result of the increased number of stress evaluation points, considerable improvements in the accuracy of reliability analyses were realized.

Thalassaemia and risk of cancer: a population-based cohort study.

PubMed

Chung, Wei-Sheng; Lin, Chun-Liang; Lin, Cheng-Li; Kao, Chia-Hung

2015-11-01

Studies that have investigated the epidemiological relationship between thalassaemia and cancers are scarce. Therefore, we conducted a longitudinal nationwide cohort study to determine whether patients with thalassaemia are at an increased risk of cancer. We investigated the incidence and risk of cancer in 2655 patients diagnosed with thalassaemia between 1998 and 2010 by using data from the Taiwan Longitudinal Health Insurance Database. The comparison cohort comprised 10 620 people from the general population without thalassaemia. The follow-up period extended from the diagnostic date for thalassaemia to the date of a cancer diagnosis, censoring or 31 December 2011. We used Cox proportional hazard regression models to analyse the risks of cancer. The incidences of cancer were 3.96 and 2.60/1000 person-years for the thalassaemia and comparison cohorts, respectively. The overall incidence of cancer was 52% higher in the thalassaemia cohort than in the comparison cohort, with an adjusted HR (aHR) of 1.54 (95% CI 1.15 to 2.07). Patients with thalassaemia had a considerably higher risk of haematological malignancy (aHR=5.32, 95% CI 2.18 to 13.0) and abdominal cancer (aHR=1.96, 95% CI 1.22 to 3.15) than did the comparison cohort. Furthermore, patients with thalassaemia with transfusion exhibited a 9.31-fold risk for developing haematological malignancy and a 9.12-fold risk for developing abdominal cancer compared with those who did not receive transfusion. This nationwide retrospective cohort study indicates that patients with thalassaemia carried substantial risks of haematological malignancy and abdominal cancer compared with those of the general population. 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.

Distress among young adult cancer survivors: a cohort study.

PubMed

Yanez, Betina; Garcia, Sofia F; Victorson, David; Salsman, John M

2013-09-01

Being diagnosed with cancer as a young adult can lead to significant psychological distress and impaired quality of life. Compared to children and older adults diagnosed with cancer, fewer studies have addressed psychological distress among young adult cancer survivors. This study sought to identify the prevalence of, and factors associated with, distress among young adult cancer survivors (ages 18-39). Young adult cancer survivors (N = 335, mean age = 31.8, women = 68.4%) were recruited from an online research panel and stratified by cohort (time postactive treatment: 0-12, 13-24, and 25-60 months). Participants completed measures assessing demographic and clinical characteristics, global impact of cancer, cancer-related education and work interruption, and cancer-specific distress using the impact of event scale (IES). The mean score on the IES (M = 31.0, range = 0-75) was above the cut point of 20, suggesting clinically elevated distress. Analysis of covariance revealed significant main effects for cohort, global impact and cancer-related education/work interruption, and an interaction between cohort and cancer-related education/work interruption on distress. Although there was no significant effect of education/work interruption on distress for those in the 0-12 month cohort (p = .88), survivors in the 13-24 and 25-60 month cohorts reporting education/work interruption were significantly more distressed than those not reporting education/work interruption in the respective cohorts (p < .05). Young adult cancer survivors face unique challenges. These data underscore the importance of attending to cancer-related distress beyond the completion of treatment and may help inform targeted interventions to prevent or reduce significant distress and related sequelae in this population.

STATUS REPORT, BEGIN TO DEVELOP COMPLETE OPERATIONS MANUALS FOR THE COHORT: PREPARE TO IMPLEMENT A COHORT STUDY OF CHILDREN'S ENVIRONMENTAL HEALTH

EPA Science Inventory

As a precursor to the National Children's Study (NCS), the North Carolina Cohort Study (NC Cohort Study) will provide the opportunity to field test procedures to better inform the implementation of the NCS. In order to test some of the study hypotheses, it will be important to ob...

Cohort Profile: Sympathetic activity and Ambulatory Blood Pressure in Africans (SABPA) prospective cohort study.

PubMed

Malan, Leoné; Hamer, Mark; Frasure-Smith, Nancy; Steyn, Hendrik S; Malan, Nicolaas T

2015-12-01

Adapting to an over-demanding stressful urban environment may exhaust the psychophysiological resources to cope with these demands, and lead to sympathetic nervous system dysfunction. The evidence that an urban-dwelling lifestyle may be detrimental to the cardiometabolic health of Africans motivated the design of the Sympathetic activity and Ambulatory Blood Pressure in African Prospective cohort study. We aimed to determine neural mechanistic pathways involved in emotional distress and vascular remodelling. The baseline sample included 409 teachers representing a bi-ethnic sex cohort from South Africa. The study was conducted in 2008-09 and repeated after 3-year follow-up in 2011-12, with an 87.8% successful follow-up rate. Seasonal changes were avoided and extensive clinical assessments were performed in a well-controlled setting. Data collection included sociodemographics, lifestyle habits, psychosocial battery and genetic analysis, mental stress responses mimicking daily life stress (blood pressure and haemostatic, cardiometabolic, endothelial and stress hormones). Target organ damage was assessed in the brain, heart, kidney, blood vessels and retina. A unique highly phenotyped cohort is presented that can address the role of a hyperactive sympathetic nervous system and neural response pathways contributing to the burden of cardiometabolic diseases in Africans. © The Author 2014. Published by Oxford University Press on behalf of the International Epidemiological Association.

Study design of DIACORE (DIAbetes COhoRtE) – a cohort study of patients with diabetes mellitus type 2

PubMed Central

2013-01-01

Background Diabetes mellitus type 2 (DM2) is highly associated with increased risk for chronic kidney disease (CKD), end stage renal disease (ESRD) and cardiovascular morbidity. Epidemiological and genetic studies generate hypotheses for innovative strategies in DM2 management by unravelling novel mechanisms of diabetes complications, which is essential for future intervention trials. We have thus initiated the DIAbetes COhoRtE study (DIACORE). Methods DIACORE is a prospective cohort study aiming to recruit 6000 patients of self-reported Caucasian ethnicity with prevalent DM2 for at least 10 years of follow-up. Study visits are performed in University-based recruiting clinics in Germany using standard operating procedures. All prevalent DM2 patients in outpatient clinics surrounding the recruiting centers are invited to participate. At baseline and at each 2-year follow-up examination, patients are subjected to a core phenotyping protocol. This includes a standardized online questionnaire and physical examination to determine incident micro- and macrovascular DM2 complications, malignancy and hospitalization, with a primary focus on renal events. Confirmatory outcome information is requested from patient records. Blood samples are obtained for a centrally analyzed standard laboratory panel and for biobanking of aliquots of serum, plasma, urine, mRNA and DNA for future scientific use. A subset of the cohort is subjected to extended phenotyping, e.g. sleep apnea screening, skin autofluorescence measurement, non-mydriatic retinal photography and non-invasive determination of arterial stiffness. Discussion DIACORE will enable the prospective evaluation of factors involved in DM2 complication pathogenesis using high-throughput technologies in biosamples and genetic epidemiological studies. PMID:23409726

Fabrication of CMC-g-PAM Superporous Polymer Monoliths via Eco-Friendly Pickering-MIPEs for Superior Adsorption of Methyl Violet and Methylene Blue

PubMed Central

Wang, Feng; Zhu, Yongfeng; Wang, Wenbo; Zong, Li; Lu, Taotao; Wang, Aiqin

2017-01-01

A series of superporous carboxymethylcellulose-graft-poly(acrylamide)/palygorskite (CMC-g-PAM/Pal) polymer monoliths presenting interconnected pore structure and excellent adsorption properties were prepared by one-step free-radical grafting polymerization reaction of CMC and acrylamide (AM) in the oil-in-water (O/W) Pickering-medium internal phase emulsions (Pickering-MIPEs) composed of non-toxic edible oil as a dispersion phase and natural Pal nanorods as stabilizers. The effects of Pal dosage, AM dosage, and co-surfactant Tween-20 (T-20) on the pore structures of the monoliths were studied. It was revealed that the well-defined pores were formed when the dosages of Pal and T-20 are 9–14 and 3%, respectively. The porous monolith can rapidly adsorb 1,585 mg/g of methyl violet (MV) and 1,625 mg/g of methylene blue (MB). After the monolith was regenerated by adsorption-desorption process for five times, the adsorption capacities still reached 92.1% (for MV) and 93.5% (for MB) of the initial maximum adsorption capacities. The adsorption process was fitted with Langmuir adsorption isotherm model and pseudo-second-order adsorption kinetic model very well, which indicate that mono-layer chemical adsorption mainly contribute to the high-capacity adsorption for dyes. The superporous polymer monolith prepared from eco-friendly Pickering-MIPEs shows good adsorption capacity and fast adsorption rate, which is potential adsorbent for the decontamination of dye-containing wastewater. PMID:28642862

Fabrication of CMC-g-PAM Superporous Polymer Monoliths via Eco-Friendly Pickering-MIPEs for Superior Adsorption of Methyl Violet and Methylene Blue.

PubMed

Wang, Feng; Zhu, Yongfeng; Wang, Wenbo; Zong, Li; Lu, Taotao; Wang, Aiqin

2017-01-01

A series of superporous carboxymethylcellulose- graft -poly(acrylamide)/palygorskite (CMC- g -PAM/Pal) polymer monoliths presenting interconnected pore structure and excellent adsorption properties were prepared by one-step free-radical grafting polymerization reaction of CMC and acrylamide (AM) in the oil-in-water (O/W) Pickering-medium internal phase emulsions (Pickering-MIPEs) composed of non-toxic edible oil as a dispersion phase and natural Pal nanorods as stabilizers. The effects of Pal dosage, AM dosage, and co-surfactant Tween-20 (T-20) on the pore structures of the monoliths were studied. It was revealed that the well-defined pores were formed when the dosages of Pal and T-20 are 9-14 and 3%, respectively. The porous monolith can rapidly adsorb 1,585 mg/g of methyl violet (MV) and 1,625 mg/g of methylene blue (MB). After the monolith was regenerated by adsorption-desorption process for five times, the adsorption capacities still reached 92.1% (for MV) and 93.5% (for MB) of the initial maximum adsorption capacities. The adsorption process was fitted with Langmuir adsorption isotherm model and pseudo-second-order adsorption kinetic model very well, which indicate that mono-layer chemical adsorption mainly contribute to the high-capacity adsorption for dyes. The superporous polymer monolith prepared from eco-friendly Pickering-MIPEs shows good adsorption capacity and fast adsorption rate, which is potential adsorbent for the decontamination of dye-containing wastewater.

Historic cohort study in Montreal's fur industry.

PubMed

Guay, D; Siemiatycki, J

1987-01-01

A historic cohort mortality study was carried out among two groups of male workers in the Montreal fur industry: 263 dressers and dyers and 599 fur garment manufacturers. The first group is exposed to a very wide variety of chemicals used in tanning, cleaning, and dyeing fur, including substances considered to be carcinogenic and/or mutagenic. The second group is exposed to residue from the dressing and dyeing stage and to respirable fur dust. The cohorts consisted of all active members of two unions as of January 1, 1966. The mean age of the workers was 43.2 and the mean number of years since first employment 14.1. The follow-up period was from January 1, 1966, to December 31, 1981; 95% of the workers were successfully traced. Observed deaths were compared with those expected based on mortality rates of the population of metropolitan Montreal. Standardized mortality ratios (SMRs) for the manufacturers were significantly low, probably because of the ethnic composition of the cohort and a healthy worker effect. SMRs for the dressers and dyers were also low, but not as low as for the manufacturers. When attention was restricted to the French Canadians in the cohort, the observed deaths were close to the expected; there was a noteworthy excess of colorectal cancer (four observed, 0.8 expected) for dressers and dyers. Apart from this weak suggestive evidence, the results did not indicate any excess mortality risks in the fur industry. However, because of the relatively small number of expected and observed deaths in the cohort and especially among the heavily exposed dressers and dyers, the confidence intervals around SMR estimates were wide and excess risks cannot be ruled out.

Cohort profile: The Canadian HIV Women’s Sexual and Reproductive Health Cohort Study (CHIWOS)

PubMed Central

de Pokomandy, Alexandra; Kennedy, V. Logan; Carter, Allison; O’Brien, Nadia; Proulx-Boucher, Karène; Ding, Erin; Lewis, Johanna; Nicholson, Valerie; Beaver, Kerrigan; Greene, Saara; Tharao, Wangari; Benoit, Anita; Dubuc, Danièle; Thomas-Pavanel, Jamie; Sereda, Paul; Jabbari, Shahab; Shurgold, Jayson H.; Colley, Guillaume; Hogg, Robert S.; Kaida, Angela

2017-01-01

Globally, women are at increased vulnerability to HIV due to biological, social, structural, and political reasons. Women living with HIV also experience unique issues related to their medical and social healthcare, which makes a clinical care model specific to their needs worthy of exploration. Furthermore, there is a dearth of research specific to women living with HIV. Research for this population has often been narrowly focused on pregnancy-related issues without considering their complex structural inequalities, social roles, and healthcare and biological needs. For these reasons, we have come together, as researchers, clinicians and community members in Canada, to develop the Canadian HIV Women’s Sexual and Reproductive Health Cohort Study (CHIWOS) to investigate the concept of women-centred HIV care (WCHC) and its impact on the overall, HIV, women’s, mental, sexual, and reproductive health outcomes of women living with HIV. Here, we present the CHIWOS cohort profile, which describes the cohort and presents preliminary findings related to perceived WCHC. CHIWOS is a prospective, observational cohort study of women living with HIV in British Columbia (BC), Ontario, and Quebec. Two additional Canadian provinces, Saskatchewan and Manitoba, will join the cohort in 2018. Using community-based research principles, CHIWOS engages women living with HIV throughout the entire research process meeting the requirements of the ‘Greater Involvement of People living with HIV/AIDS’. Study data are collected through an interviewer-administered questionnaire that uses a web-based platform. From August 2013 to May 2015, a total of 1422 women living with HIV in BC, Ontario, and Quebec were enrolled and completed the baseline visit. Follow-up interviews are being conducted at 18-month intervals. Of the 1422 participants at baseline, 356 were from BC (25%), 713 from Ontario (50%), 353 from Quebec (25%). The median age of the participants at baseline was 43 years (range, 16

Sardasht-Iran cohort study of chemical warfare victims: design and methods.

PubMed

Ghazanfari, Tooba; Faghihzadeh, Soghrat; Aragizadeh, Hassan; Soroush, Mohammad-Reza; Yaraee, Roya; Mohammad Hassan, Zuhair; Foroutan, Abbas; Vaez-Mahdavi, Mohammad-Reza; Javadi, Mohammad-Ali; Moaiedmohseni, Sakine; Azizi, Fereidoun; Panahi, Yunes; Mostafaie, Ali; Ghasemi, Hassan; Shams, Jalaleddin; Pourfarzam, Shahryar; Jalali-Nadoushan, Mohammad-Reza; Fallahi, Faramarz; Ebtekar, Massoumeh; Davoudi, Seyyed-Masoud; Ghazanfari, Zeinab; Ardestani, Sussan K; Shariat-Panahi, Shamsa; Moin, Athar; Rezaei, Abbas; Kariminia, Amina; Ajdary, Soheila; Mahmoudi, Mahmoud; Roshan, Rasoul; Ghaderi, Sulayman; Babai, Mahmoud; Naghizadeh, Mohammad-Mehdi; Ghanei, Mohammad-Mostafa

2009-01-01

Insights into long-term clinical consequences of sulfur mustard have emerged from some investigations but less is known about the basic and molecular mechanisms of these complications. Sardasht-Iran Cohort Study is a comprehensive historical cohort study on Sardasht chemical victims' population which was designed to find out the long-term complications of sulfur mustard exposure and the basic mechanisms underlying clinical manifestations. This paper describes the design and methodology of Sardasht-Iran Cohort Study. In Sardasht-Iran Cohort Study, 500 individuals including 372 subjects from Sardasht, as the exposed group, and 128 subjects from Rabat, as the unexposed age-matched control group were evaluated. The exposed group was divided into two groups based on the severity of clinical complications at the time of exposure. Different samples including blood, sputum, saliva, tear, urine, and semen were collected for immunologic, hematologic, biochemical, and other laboratory analysis. Data were gathered from medical records, clinical examinations, laboratory tests, and questionnaires for psychological and lifestyle situations. The important distinctions setting this study apart from the previous ones are discussed. The Sardasht-Iran Cohort Study provides important information on various aspects of long-term consequences of sulfur mustard exposure. This database will provide a better position to suggest guidelines for the diagnosis, treatment, and prevention of delayed complications in the patients exposed to sulfur mustard.

Dementia and vagotomy in Taiwan: a population-based cohort study

PubMed Central

Lin, Shih-Yi; Lin, Cheng-Li; Wang, I-Kuan; Lin, Cheng-Chieh; Lin, Chih-Hsueh; Hsu, Wu-Huei

2018-01-01

Objective Truncal vagotomy is associated with a decreased risk of subsequent Parkinson disease (PD), although the effect of vagotomy on dementia is unclear. In response, we investigated the risk of dementia in patients who underwent vagotomy. Setting Population-based cohort study. Participants A total of 155 944 patients who underwent vagotomy (vagotomy cohort) and 155 944 age-matched, sex-matched and comorbidity-matched controls (non-vagotomy cohort) were identified between 2000 and 2011. Primary and secondary outcome measures All patient data were tracked until the diagnosis of dementia, death or the end of 2011. The cumulative incidence of subsequent dementia and HRs were calculated. Results The mean ages of the study patients in the vagotomy and non-vagotomy cohorts were 56.6±17.4 and 56.7±17.3 years, respectively. The overall incidence density rate for dementia was similar in the vagotomy and non-vagotomy cohorts (2.43 and 2.84 per 1000 person-years, respectively). After adjustment for age, sex and comorbidities such as diabetes, hypertension, hyperlipidaemia, stroke, depression, coronary artery disease and PD, the patients in the vagotomy cohort were determined to not be at a higher risk of dementia than those in the non-vagotomy cohort (adjusted HR=1.09, 95% CI 0.87 to 1.36). Moreover, the patients who underwent truncal vagotomy were not associated with risk of dementia (adjusted HR=1.04, 95% CI 0.87 to 1.25), compared with the patients who did not undergo vagotomy. Conclusion Vagotomy, either truncal or selective, is not associated with risk of dementia. PMID:29602843

Diagnosing Meteorological Conditions Associated with Sprites and Lightning with Large Charge Moment Changes (CMC) over Oklahoma

NASA Technical Reports Server (NTRS)

Rivera, Lizxandra Flores; Lang, Timothy

2014-01-01

Sprites are a category of Transient Luminous Events (TLEs) that occur in the upper atmosphere above the tops of Mesoscale Convective Systems (MCSs). They are commonly associated with lightning strokes that produce large charge moment changes (CMCs). Synergistic use of satellite and radar-retrieved observations together with sounding data, forecasts, and lightning-detection networks allowed the diagnosis and analysis of the meteorological conditions associated with sprites as well as large-CMC lightning over Oklahoma. One goal of the NASA-funded effort reported herein is the investigation of the potential for sprite interference with aerospace activities in the 20- 100km altitude range, including research balloons, space missions and other aviation transports.

Fluorophotometric determination of critical micelle concentration (CMC) of ionic and non-ionic surfactants with carbon dots via Stokes shift.

PubMed

Lavkush Bhaisare, Mukesh; Pandey, Sunil; Shahnawaz Khan, M; Talib, Abou; Wu, Hui-Fen

2015-01-01

A new and facile method for the determination of critical micelle concentration (CMC) of ionic and non-ionic surfactants is proposed in this article. Carbon dots exhibited substantial fluorescence and therefore enhanced the sensitivity of this evaluation. Understanding the formation of surfactant micelles is vital for the applications of biomedicine such as drug fabrication and smart molecular vehicles in delivering therapeutic dosage to various molecular sites. The fluorescence property of carbon dots was utilized for the first time to estimate the critical micelle concentration of surfactants. The central concept of the approach is based on the Stokes shift determination of a system composed of constant amount of carbon dots with varying concentrations of ionic and non-ionic surfactants. The synthesized carbon dots were characterized by FTIR, TEM, XRD, Raman, UV, and fluorescence spectroscope. The carbon dots were excited at 280 nm so as to obtain maximum emission for the Stokes shift measurement. The CMC value of cetyltrimethyl ammonium bromide (CTAB), sodium dodecyl sulfate (SDS), Triton X-100, dodecyldimethyl(3-sulfopropyl)ammonium hydroxide (SB-12) evaluated by this approach was found to be 0.98, 7.3, 0.19, and 3.5mM, respectively. The signals of spectra were assigned and explained in terms of both electron transitions between specific molecular orbital and the interaction with solvent. Copyright © 2014 Elsevier B.V. All rights reserved.

"The Refer Less Resolve More" Initiative: A Five-year Experience from CMC Vellore, India.

PubMed

Velavan, Jachin

2012-01-01

India's one billion plus strong population presents huge health care needs. Presently, approximately 250,000 general practitioners and 30,000 Government doctors are a part of the Indian healthcare workforce, but 80% of them are based in urban India. Problems which plague healthcare delivery and attributed to physician practice may be enumerated as - physicians (1) lack competencies, (2) lack updating, (3) prescribe irrationally (pressures from pharmaceutical companies and patients), (4) practice unethically, (5) refer excessively to specialists and other clinical professionals, and (6) investigate for diseases without justification. A multi-competent Family Physician who could provide a single-window, ethical, and holistic healthcare to patients and families is the need of the hour. Therefore, training, equipping, and empowering these 250,000 doctors to become such physicians will reduce health costs considerably. Distance medical education using all the andragogic methods can be used to train large number of individuals without displacing them from their work-places. Distance learning provides a useful interface for rapidly developing a specialized pool of doctors practicing and advocating family medicine as most-needed discipline. This motivated CMC Vellore, a premier institution for medical education in India, to start a the "refer less resolve more initiative" by offering "two year family medicine diploma course" by distance mode. This is an innovatively-written program consisting of problem-based self-learning modules, video-lectures, video-conferencing, and face-to-face contact programs. Ten secondary level hospitals, across the country, under the supervision of national and international family medicine faculty form the pillars of this program. This distance learning program offered by CMC Vellore has become the platform for change as there is special focus is on ethics, rational prescribing, consultation skills, application of family medicine principles

Comparison of Estimates between Cohort and Case-Control Studies in Meta-Analyses of Therapeutic Interventions: A Meta-Epidemiological Study.

PubMed

Lanza, Amy; Ravaud, Philippe; Riveros, Carolina; Dechartres, Agnes

2016-01-01

Observational studies are increasingly being used for assessing therapeutic interventions. Case-control studies are generally considered to have greater risk of bias than cohort studies, but we lack evidence of differences in effect estimates between the 2 study types. We aimed to compare estimates between cohort and case-control studies in meta-analyses of observational studies of therapeutic interventions by using a meta-epidemiological study. We used a random sample of meta-analyses of therapeutic interventions published in 2013 that included both cohort and case-control studies assessing a binary outcome. For each meta-analysis, the ratio of estimates (RE) was calculated by comparing the estimate in case-control studies to that in cohort studies. Then, we used random-effects meta-analysis to estimate a combined RE across meta-analyses. An RE < 1 indicated that case-control studies yielded larger estimates than cohort studies. The final analysis included 23 meta-analyses: 138 cohort and 133 case-control studies. Treatment effect estimates did not significantly differ between case-control and cohort studies (combined RE 0.97 [95% CI 0.86-1.09]). Heterogeneity was low, with between-meta-analysis variance τ2 = 0.0049. Estimates did not differ between case-control and prospective or retrospective cohort studies (RE = 1.05 [95% CI 0.96-1.15] and RE = 0.99 [95% CI, 0.83-1.19], respectively). Sensitivity analysis of studies reporting adjusted estimates also revealed no significant difference (RE = 1.03 [95% CI 0.91-1.16]). Heterogeneity was also low for these analyses. We found no significant difference in treatment effect estimates between case-control and cohort studies assessing therapeutic interventions.

CMC stabilized nano silver synthesis, characterization and its antibacterial and synergistic effect with broad spectrum antibiotics.

PubMed

Prema, P; Thangapandiyan, S; Immanuel, G

2017-02-20

In the present study silver nanoparticles were synthesized by reduction of AgNO 3 using aqueous CMC solution, which acts as both reducing and capping agent. The formation of AgNO 3 nanoparticles was observed visually by color change and these nanoparticles were characterized through UV-vis spectroscopy, FTIR, XRD, SEM, EDS and AFM. The FTIR peaks observed to be ranging from 3300 to 605cm -1 . The AFM image clearly showed the surface morphology of well dispersed nanoparticles. SEM image illustrates the nanoparticles with spherical shape. The crystalline nature of the particles was assured by XRD analysis. The antimicrobial activity of nanoparticles was tested against human bacterial pathogens (Bacillus cereus, Staphylococcus aureus, S. epidermidis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhimurium &Vibrio vulnificus). The bacterial growth was highly inhibited by the nanoparticles. The synergistic effect of nanoparticles in combination with selected broad spectrum antibiotics against the tested bacteria determined strong growth inhibitory activity. Copyright © 2016. Published by Elsevier Ltd.

Possibilities and considerations when merging dietary data from the world's two largest pregnancy cohorts: the Danish National Birth Cohort and the Norwegian Mother and Child Cohort Study.

PubMed

Olsen, Sjurdur F; Birgisdottir, Bryndis Eva; Halldorsson, Thorhallur I; Brantsaeter, Anne Lise; Haugen, Margaretha; Torjusen, Hanne; Petersen, Sesilje B; Strøm, Marin; Meltzer, Helle Margrete

2014-11-01

To elucidate the research possibilities when merging data on maternal diet from the Danish National Birth Cohort (DNBC) and the Norwegian Mother and Child Cohort Study (MoBa), through comparison of (i) the methodology used for dietary assessment and (ii) the estimated intake of selected food groups in the two cohorts. Qualitative and quantitative comparison of the two dietary databases. Two national prospective pregnancy cohorts. Denmark, Norway. Comparison of food intake using food frequency questionnaires (FFQs). The FFQs had overlapping time windows and a majority of the questions in the two FFQs were comparable. Calculation principles shared similar features, including the software used and use of global questions to calibrate intakes of different food groups. A total of 63 food groups were defined that could be compared across the two cohorts; these were further aggregated down to 31 broader groups. A comparison of food intakes (grams/d) showed 39, 74 and 141% lower daily intakes of fish, potatoes and rice, respectively, in DNBC vs. MoBa and 39, 54 and 65% higher daily intakes of milk, butter and potatoes in DNBC vs. MoBa. For most other food groups, differences in consumption data were below 20%. The two FFQs are to a large extent compatible and substantial differences in dietary habits were observed between the two cohorts. This may strengthen studies using pooled analysis to examine diet-disease relations. This is a conclusion of great importance given the colossal and costly task involved to establish each of these two cohorts. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

Incidence of cancer among UK Gulf war veterans: cohort study.

PubMed

Macfarlane, Gary J; Biggs, Anne-Marie; Maconochie, Noreen; Hotopf, Matthew; Doyle, Patricia; Lunt, Mark

2003-12-13

To determine whether incidence rates of cancer are higher in UK service personnel who were deployed in the Gulf war than in those not deployed and whether any increased risk of cancer is related to self reported exposures to potentially hazardous material during the period of deployment. A cohort study with follow up from 1 April 1991 (the end of the Gulf war) to 31 July 2002. 51 721 Gulf war veterans and 50 755 service personnel matched for age, sex, rank, service, and level of fitness who were not deployed in the Gulf (the Era cohort). Incident cancers, identified on the NHS central register. There were 270 incident cancers among the Gulf cohort and 269 among the Era cohort (incidence rate ratio 0.99, 95% confidence interval 0.83 to 1.17). There was no excess in site specific cancers among the Gulf cohort. Adjustment for lifestyle factors (smoking and alcohol consumption) did not alter these results. In the Gulf cohort, risk of cancer was not related to multiple vaccinations or exposure to pesticides or depleted uranium during deployment. There is no current excess risk of cancer overall nor of site specific cancers in Gulf war veterans. Specific exposures during deployment have not resulted in a subsequent increased risk of cancer. The long latent period for cancer, however, necessitates the continued follow up of these cohorts.

What Drives Teacher Engagement: A Study of Different Age Cohorts

ERIC Educational Resources Information Center

Guglielmi, Dina; Bruni, Ilaria; Simbula, Silvia; Fraccaroli, Franco; Depolo, Marco

2016-01-01

Despite the growing body of research on work engagement, little is known about what drives work engagement among different age cohorts. This study aims to investigate whether engagement varies across age cohorts and examines the job resources that foster teacher engagement. A questionnaire was distributed to 537 teachers who were employed in…

An Update on Design Tools for Optimization of CMC 3D Fiber Architectures

NASA Technical Reports Server (NTRS)

Lang, J.; DiCarlo, J.

2012-01-01

Objective: Describe and up-date progress for NASA's efforts to develop 3D architectural design tools for CMC in general and for SIC/SiC composites in particular. Describe past and current sequential work efforts aimed at: Understanding key fiber and tow physical characteristics in conventional 2D and 3D woven architectures as revealed by microstructures in the literature. Developing an Excel program for down-selecting and predicting key geometric properties and resulting key fiber-controlled properties for various conventional 3D architectures. Developing a software tool for accurately visualizing all the key geometric details of conventional 3D architectures. Validating tools by visualizing and predicting the Internal geometry and key mechanical properties of a NASA SIC/SIC panel with a 3D orthogonal architecture. Applying the predictive and visualization tools toward advanced 3D orthogonal SiC/SIC composites, and combining them into a user-friendly software program.

Sequential anaerobic-aerobic biodegradation of 2,3,7,8-TCDD contaminated soil in the presence of CMC-coated nZVI and surfactant.

PubMed

Binh, Nguyen Duy; Imsapsangworn, Chaiyaporn; Kim Oanh, Nguyen Thi; Parkpian, Preeda; Karstensen, Kare; Giao, Pham Huy; DeLaune, Ronald D

2016-01-01

Enriched microorganisms in sediment collected from a dioxin-contaminated site in Vietnam (Bien Hoa airbase) were used for examining the effectiveness in biological treatment of 2,3,7,8-Tetrachlorodibenzo-p-dioxin in soil. Four bio-treatments were investigated using a sequential anaerobic (17 weeks) followed by an aerobic (6 weeks) incubation. The maximum removal efficiency was approximately 60% even at an extremely low pH (approx. 3.6) condition. Surfactant Tween-80 was added to enhance the bioavailability of dioxin in two treatments, but it appeared to biostimulate methanogens rather than dechlorinators. As a result, methane production was the highest while the dioxin removal efficiency was the lowest, as compared with the other bio-treatments. Carboxymethylcellulose (CMC) coated on nanoscale zero valent iron (nZVI) surface used in two treatments could prevent the direct contact between bacterial cell surface and nZVI which prevented cell death and lysis, hence enhancing dioxin removal. The presence of CMC--_nZVI in bio-treatments gradually released H2 required for microbiological processes, but the amount used in the experiments were likely too high to maintain optimum H2 levels for biostimulating dechlorinators rather than methanogens.

Cohort profile: the Italian Network of Longitudinal Metropolitan Studies (IN-LiMeS), a multicentre cohort for socioeconomic inequalities in health monitoring

PubMed Central

Giorgi Rossi, Paolo; Spadea, Teresa; Pacelli, Barbara; Broccoli, Serena; Ballotari, Paola; Costa, Giuseppe; Zengarini, Nicolás; Agabiti, Nera; Bargagli, Anna Maria; Cacciani, Laura; Canova, Cristina; Cestari, Laura; Biggeri, Annibale; Grisotto, Laura; Terni, Gianna; Costanzo, Gianfranco; Mirisola, Concetta; Petrelli, Alessio

2018-01-01

Purpose The Italian Network of Longitudinal Metropolitan Studies (IN-LiMeS) is a system of integrated data on health outcomes, demographic and socioeconomic information, and represents a powerful tool to study health inequalities. Participants IN-LiMeS is a multicentre and multipurpose pool of metropolitan population cohorts enrolled in nine Italian cities: Turin, Venice, Reggio Emilia, Modena, Bologna, Florence, Leghorn, Prato and Rome. Data come from record linkage of municipal population registries, the 2001 population census, mortality registers and hospital discharge archives. Depending on the source of enrolment, cohorts can be closed or open. The census-based closed cohort design includes subjects resident in any of the nine cities at the 2001 census day; 4 466 655 individuals were enrolled in 2001 in the nine closed cohorts. The open cohort design includes subjects resident in 2001 or subsequently registered by birth or immigration until the latest available follow-up (currently 31 December 2013). The open cohort design is available for Turin, Venice, Reggio Emilia, Modena, Bologna, Prato and Rome. Detailed socioeconomic data are available for subjects enrolled in the census-based cohorts; information on demographic characteristics, education and citizenship is available from population registries. Findings to date The first IN-LiMeS application was the study of differentials in mortality between immigrants and Italians. Either using a closed cohort design (nine cities) or an open one (Turin and Reggio Emilia), individuals from high migration pressure countries generally showed a lower mortality risk. However, a certain heterogeneity between the nine cities was noted, especially among men, and an excess mortality risk was reported for some macroareas of origin and specific causes of death. Future plans We are currently working on the linkage of the 2011 population census data, the expansion of geographical coverage and the implementation of the open design

Incidence of cancer among UK Gulf war veterans: cohort study

PubMed Central

Macfarlane, Gary J; Biggs, Anne-Marie; Maconochie, Noreen; Hotopf, Matthew; Doyle, Patricia; Lunt, Mark

2003-01-01

Objectives To determine whether incidence rates of cancer are higher in UK service personnel who were deployed in the Gulf war than in those not deployed and whether any increased risk of cancer is related to self reported exposures to potentially hazardous material during the period of deployment. Design A cohort study with follow up from 1 April 1991 (the end of the Gulf war) to 31 July 2002. Participants 51 721 Gulf war veterans and 50 755 service personnel matched for age, sex, rank, service, and level of fitness who were not deployed in the Gulf (the Era cohort). Main outcome measures Incident cancers, identified on the NHS central register. Results There were 270 incident cancers among the Gulf cohort and 269 among the Era cohort (incidence rate ratio 0.99, 95% confidence interval 0.83 to 1.17). There was no excess in site specific cancers among the Gulf cohort. Adjustment for lifestyle factors (smoking and alcohol consumption) did not alter these results. In the Gulf cohort, risk of cancer was not related to multiple vaccinations or exposure to pesticides or depleted uranium during deployment. Conclusion There is no current excess risk of cancer overall nor of site specific cancers in Gulf war veterans. Specific exposures during deployment have not resulted in a subsequent increased risk of cancer. The long latent period for cancer, however, necessitates the continued follow up of these cohorts. PMID:14670879

Two Studies Examining Argumentation in Asynchronous Computer Mediated Communication

ERIC Educational Resources Information Center

Joiner, Richard; Jones, Sarah; Doherty, John

2008-01-01

Asynchronous computer mediated communication (CMC) would seem to be an ideal medium for supporting development in student argumentation. This paper investigates this assumption through two studies. The first study compared asynchronous CMC with face-to-face discussions. The transactional and strategic level of the argumentation (i.e. measures of…

The role of birth cohorts in studies of adult health: the New York women's birth cohort.

PubMed

Terry, Mary Beth; Flom, Julie; Tehranifar, Parisa; Susser, Ezra

2009-09-01

Epidemiological studies investigating associations between early life factors and adult health are often limited to studying exposures that can be reliably recalled in adulthood or obtained from existing medical records. There are few US studies with detailed data on the pre- and postnatal environment whose study populations are now in adulthood; one exception is the Collaborative Perinatal Project (CPP). We contacted former female participants of the New York site of the CPP who were born from 1959 to 1963 and were prospectively followed for 7 years to examine whether the pre- and postnatal environment is associated with adult health in women 40 years after birth. The New York CPP cohort is particularly diverse; at enrolment, the race/ethnicity distribution of mothers was approximately 30% White, 40% Black and 30% Puerto Rican. Of the 841 eligible women, we successfully traced 375 women (45%) and enrolled 262 women (70% of those traced). Baseline data were available for all eligible women, and we compared those who participated with the remaining cohort (n = 579). Higher family socio-economic status at age 7, availability of maternal social security number, and White race/ethnicity were statistically significantly associated with a higher probability of tracing. Of those traced, race/ethnicity was associated with participation, with Blacks and Puerto Ricans less likely to participate than Whites (OR = 0.5, 95% CI 0.3, 0.8, and OR = 0.5, 95% CI 0.3, 1.0, respectively). In addition, higher weight at 7 years was associated with lower participation (OR = 0.95, 95% CI 0.92, 0.99), but this association was observed only among the non-White participants. None of the other maternal characteristics, infant or early childhood growth measures was associated with participation or with tracing, either overall or within each racial/ethnic subgroup. Daughters' recall of early life factors such as pre-eclampsia (sensitivity = 24%) and birthweight were generally poor, with the

Characterization of LWRS Hybrid SiC-CMC-Zircaloy-4 Fuel Cladding after Gamma Irradiation

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

Isabella J van Rooyen

2012-09-01

The purpose of the gamma irradiation tests conducted at the Idaho National Laboratory (INL) was to obtain a better understanding of chemical interactions and potential changes in microstructural properties of a mock-up hybrid nuclear fuel cladding rodlet design (unfueled) in a simulated PWR water environment under irradiation conditions. The hybrid fuel rodlet design is being investigated under the Light Water Reactor Sustainability (LWRS) program for further development and testing of one of the possible advanced LWR nuclear fuel cladding designs. The gamma irradiation tests were performed in preparation for neutron irradiation tests planned for a silicon carbide (SiC) ceramic matrixmore » composite (CMC) zircaloy-4 (Zr-4) hybrid fuel rodlet that may be tested in the INL Advanced Test Reactor (ATR) if the design is selected for further development and testing« less

Cohort Profile Update: The Norwegian Mother and Child Cohort Study (MoBa).

PubMed

Magnus, Per; Birke, Charlotte; Vejrup, Kristine; Haugan, Anita; Alsaker, Elin; Daltveit, Anne Kjersti; Handal, Marte; Haugen, Margaretha; Høiseth, Gudrun; Knudsen, Gun Peggy; Paltiel, Liv; Schreuder, Patricia; Tambs, Kristian; Vold, Line; Stoltenberg, Camilla

2016-04-01

This is an update of the Norwegian Mother and Child Cohort Study (MoBa) cohort profile which was published in 2006. Pregnant women attending a routine ultrasound examination were initially invited. The first child was born in October 1999 and the last in July 2009. The participation rate was 41%. The cohort includes more than 114 000 children, 95 000 mothers and 75 000 fathers. About 1900 pairs of twins have been born. There are approximately 16 400 women who participate with more than one pregnancy. Blood samples were obtained from both parents during pregnancy and from mothers and children (umbilical cord) after birth. Samples of DNA, RNA, whole blood, plasma and urine are stored in a biobank. During pregnancy, the mother responded to three questionnaires and the father to one. After birth, questionnaires were sent out when the child was 6 months, 18 months and 3 years old. Several sub-projects have selected participants for in-depth clinical assessment and exposure measures. The purpose of this update is to explain and describe new additions to the data collection, including questionnaires at 5, 7, 8 and 13 years as well as linkages to health registries, and to point to some findings and new areas of research. Further information can be found at [www.fhi.no/moba-en]. Researchers interested in collaboration and access to the data can complete an electronic application available on the MoBa website above. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Cohort profile: the Italian Network of Longitudinal Metropolitan Studies (IN-LiMeS), a multicentre cohort for socioeconomic inequalities in health monitoring.

PubMed

Caranci, Nicola; Di Girolamo, Chiara; Giorgi Rossi, Paolo; Spadea, Teresa; Pacelli, Barbara; Broccoli, Serena; Ballotari, Paola; Costa, Giuseppe; Zengarini, Nicolás; Agabiti, Nera; Bargagli, Anna Maria; Cacciani, Laura; Canova, Cristina; Cestari, Laura; Biggeri, Annibale; Grisotto, Laura; Terni, Gianna; Costanzo, Gianfranco; Mirisola, Concetta; Petrelli, Alessio

2018-04-20

The Italian Network of Longitudinal Metropolitan Studies (IN-LiMeS) is a system of integrated data on health outcomes, demographic and socioeconomic information, and represents a powerful tool to study health inequalities. IN-LiMeS is a multicentre and multipurpose pool of metropolitan population cohorts enrolled in nine Italian cities: Turin, Venice, Reggio Emilia, Modena, Bologna, Florence, Leghorn, Prato and Rome. Data come from record linkage of municipal population registries, the 2001 population census, mortality registers and hospital discharge archives. Depending on the source of enrolment, cohorts can be closed or open. The census-based closed cohort design includes subjects resident in any of the nine cities at the 2001 census day; 4 466 655 individuals were enrolled in 2001 in the nine closed cohorts. The open cohort design includes subjects resident in 2001 or subsequently registered by birth or immigration until the latest available follow-up (currently 31 December 2013). The open cohort design is available for Turin, Venice, Reggio Emilia, Modena, Bologna, Prato and Rome. Detailed socioeconomic data are available for subjects enrolled in the census-based cohorts; information on demographic characteristics, education and citizenship is available from population registries. The first IN-LiMeS application was the study of differentials in mortality between immigrants and Italians. Either using a closed cohort design (nine cities) or an open one (Turin and Reggio Emilia), individuals from high migration pressure countries generally showed a lower mortality risk. However, a certain heterogeneity between the nine cities was noted, especially among men, and an excess mortality risk was reported for some macroareas of origin and specific causes of death. We are currently working on the linkage of the 2011 population census data, the expansion of geographical coverage and the implementation of the open design in all the participating cohorts. © Article author

Study protocol title: a prospective cohort study of low back pain.

PubMed

Garg, Arun; Hegmann, Kurt T; Moore, J Steven; Kapellusch, Jay; Thiese, Matthew S; Boda, Sruthi; Bhoyr, Parag; Bloswick, Donald; Merryweather, Andrew; Sesek, Richard; Deckow-Schaefer, Gwen; Foster, James; Wood, Eric; Sheng, Xiaoming; Holubkov, Richard

2013-03-07

Few prospective cohort studies of workplace low back pain (LBP) with quantified job physical exposure have been performed. There are few prospective epidemiological studies for LBP occupational risk factors and reported data generally have few adjustments for many personal and psychosocial factors. A multi-center prospective cohort study has been incepted to quantify risk factors for LBP and potentially develop improved methods for designing and analyzing jobs. Due to the subjectivity of LBP, six measures of LBP are captured: 1) any LBP, 2) LBP ≥ 5/10 pain rating, 3) LBP with medication use, 4) LBP with healthcare provider visits, 5) LBP necessitating modified work duties and 6) LBP with lost work time. Workers have thus far been enrolled from 30 different employment settings in 4 diverse US states and performed widely varying work. At baseline, workers undergo laptop-administered questionnaires, structured interviews, and two standardized physical examinations to ascertain demographics, medical history, psychosocial factors, hobbies and physical activities, and current musculoskeletal disorders. All workers' jobs are individually measured for physical factors and are videotaped. Workers are followed monthly for the development of low back pain. Changes in jobs necessitate re-measure and re-videotaping of job physical factors. The lifetime cumulative incidence of low back pain will also include those with a past history of low back pain. Incident cases will exclude prevalent cases at baseline. Statistical methods planned include survival analyses and logistic regression. Data analysis of a prospective cohort study of low back pain is underway and has successfully enrolled over 800 workers to date.

A Cohort, Is a Cohort, Is a Cohort...or Is It?

ERIC Educational Resources Information Center

Pemberton, Cynthia Lee A.; Akkary, Rima Karami

2010-01-01

This paper presents findings from a multi-year qualitative study based upon life-history narratives of women pursuing doctoral degrees in Educational Leadership. This paper focuses on findings specific to educational cohort models, and suggests that perhaps, at least for women, naturally emergent cohorts--born of relationships of choice--may be…

Association of chronic obstructive pulmonary disease and hemorrhoids: A nationwide cohort study.

PubMed

Lin, Lih-Hwa; Siu, Justin Ji-Yuen; Liao, Po-Chi; Chiang, Jen-Huai; Chou, Pei-Chi; Chen, Huey-Yi; Ho, Tsung-Jung; Tsai, Ming-Yen; Chen, Yung-Hsiang; Chen, Wen-Chi

2017-03-01

According to traditional Chinese medicine (TCM) theory, a specific physiological and pathological relationship exists between the lungs and the large intestine. The aim of this study is to delineate the association of chronic obstructive pulmonary disease (COPD) and hemorrhoids in order to verify the "interior-exterior" relationship between the lungs and the large intestine. A retrospective cohort study is conceived from the National Health Insurance Research Database, Taiwan. The 2 samples (COPD cohort and non-COPD cohort) were selected from the 2000 to 2003 beneficiaries of the NHI, representing patients age 20 and older in Taiwan, with the follow-up ending on December 31, 2011. The COPD cohort (n = 51,506) includes every patient newly diagnosed as having Chronic Obstructive Pulmonary Disease (COPD, ICD-9-CM: 490-492, 494, 496), who have made at least 2 confirmed visits to the hospital/clinic. The non-COPD cohort (n = 103,012) includes patients without COPD and is selected via a 1:2 (COPD: non-COPD) matching by age group (per 5 years), gender, and index date (diagnosis date of COPD for the COPD cohort). Compared with non-COPD cohorts, patients with COPD have a higher likelihood of having hemorrhoids and the age-, gender- and comorbidies-adjusted hazard ratio (HR) for hemorrhoids is 1.56 (95% confidence intervals [CI]:1.50-1.62). The adjusted HR of hemorrhoids for females is 0.79 (95% CI: 0.77-0.83), which is significantly less than that for males. The elderly groups, 40 to 59 years and aged 60 or above, have higher adjusted HRs than younger age groups (20-39 years), 1.19 (95% CI: 1.14-1.26), and 1.18 (95% CI: 1.12-1.24), respectively. Patients with COPD may have a higher likelihood to have hemorrhoids in this retrospective cohort study. This study verifies the fundamental theorem of TCM that there is a definite pathogenic association between the lungs and large intestine.

Studies on Early Allergic Sensitization in the Lithuanian Birth Cohort

PubMed Central

Dubakiene, Ruta; Rudzeviciene, Odilija; Butiene, Indre; Sezaite, Indre; Petronyte, Malvina; Vaicekauskaite, Dalia; Zvirbliene, Aurelija

2012-01-01

Cohort studies are of great importance in defining the mechanism responsible for the development of allergy-associated diseases, such as atopic dermatitis, allergic asthma, and allergic rhinoconjunctivitis. Although these disorders share genetic and environmental risk factors, it is still under debate whether they are linked or develop sequentially along an atopic pathway. The current study was aimed to determine the pattern of allergy sensitization in the Lithuanian birth cohort “Alergemol” (n = 1558) established as a part of the multicenter European birth cohort “EuroPrevall”. Early sensitization to food allergens in the “Alergemol” birth cohort was analysed. The analysis revealed 1.3% and 2.8% of symptomatic-sensitized subjects at 6 and 12 months of age, respectively. The sensitization pattern in response to different allergens in the group of infants with food allergy symptoms was studied using allergological methods in vivo and in vitro. The impact of maternal and environmental risk factors on the early development of food allergy in at 6 and 12 months of age was evaluated. Our data showed that maternal diet, diseases, the use of antibiotics, and tobacco smoke during pregnancy had no significant impact on the early sensitization to food allergens. However, infants of atopic mothers were significantly more often sensitized to egg as compared to the infants of nonatopic mothers. PMID:22606067

Transcutaneous acupoint electrical stimulation pain management after surgical abortion: A cohort study.

PubMed

Feng, Xiaozhen; Ye, Tianshen; Wang, Zedong; Chen, Xiufang; Cong, Wenjie; Chen, Yong; Chen, Pinjie; Chen, Chong; Shi, Beibei; Xie, Wenxia

2016-06-01

Transcutaneous acupoint electrical stimulation (TEAS) is a standard therapy for painful conditions. This study evaluated pain-relieving effects of treatment with TEAS before and after surgical abortion. In this cohort study 140 nulliparae requesting pregnancy termination with intravenous anesthesia from August to December 2013 at the outpatient clinic of Wenzhou Medical University First Affiliated Hospital were recruited and divided into three cohorts who received TEAS pre-, post-, and both pre- and post-operation, alongside a control group. The cohorts underwent TEAS treatment for 30 min before and/or after the procedure while the control group received no TEAS treatment. Pain levels were evaluated upon recovery at 10, 30, and 45 min, respectively, after abortion. Mean Visual Analog Scale (VAS) scores in pre-operation cohorts, but not the post-operation cohort, were significantly lower than those obtained for the control group at 10 min (p < 0.01). VAS scores at 30 min and 45 min postoperatively were similar in each cohort but lower than control values (p < 0.001). More cohort patients reported mild or no pain than control patients (p < 0.05); the pre-operation cohorts had more women with no pain compared with the post-operation group (p < 0.05). There were no differences among groups in medical treatment required after 45 min. There were fewer complications of nausea and vomiting in the cohorts compared with the control group (p < 0.05). Performing TEAS before and after surgical abortion provides postoperative pain relief. However, receiving TEAS before surgery allowed more women to experience mild or no pain. Transcutaneous acupoint electrical stimulation shows potential as an adjunct to conventional pain treatment following surgical abortion in nulliparae. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Haemochromatosis: unexplained metacarpophalangeal or ankle arthropathy should prompt diagnostic tests: findings from two UK observational cohort studies.

PubMed

Richardson, A; Prideaux, A; Kiely, P

2017-01-01

To examine demographic and clinical features leading to the diagnosis of hereditary haemochromatosis and assess factors that might enhance earlier diagnosis, with particular attention to arthritic symptoms. Diagnostic features were captured directly from patients with haemochromatosis attending a specialist rheumatology clinic (group 1) and from analysis of a specifically designed questionnaire circulated to members of the UK Haemochromatosis Society (group 2). In groups 1 (n = 62) and 2 (n = 470), respectively, the diagnosis of haemochromatosis was made at a mean age of 52.8 and 56.4 years with 77% and 76% reporting joint symptoms with a mean duration of 8.3 and 8.1 years. The first joints to be affected in group 1 were the metacarpophalangeal (MCP; 38.5%) and ankle (29.5%) followed by the knee, hip, and proximal interphalangeal (PIP) joints. At the time of clinical assessment or questionnaire completion, the most prevalent regions with arthropathy in group 1 were PIP (64.5%), knee (64%), ankle (61%), and MCP (60%) and in group 2 the most prevalent joint regions self-reported were the first carpometacarpal (CMC; 59%), wrist (52%), PIP (47%), MCP (46%), knee (42%), and ankle (35%). Data from both cohorts confirm the high prevalence of joint symptoms in haemochromatosis predating the diagnosis by many years. Discriminatory features of the arthropathy include the involvement of MCP joints and ankles at a relatively young age in the absence of trauma, all of which are unusual features of primary osteoarthritis (OA). The finding of this presentation should prompt diagnostic tests for haemochromatosis.

Endometrial cancer and meat consumption: a case-cohort study.

PubMed

van Lonkhuijzen, Luc; Kirsh, Victoria A; Kreiger, Nancy; Rohan, Thomas E

2011-07-01

Diet plays an important role in the etiology of certain cancers, but there is limited evidence with regard to the association between diet and risk of endometrial cancer. Few prospective studies have investigated meat intake as a potential determinant of endometrial cancer risk. The objective of this study was to examine the association between endometrial cancer risk and total meat, red meat, processed meat, fish, and poultry intake. We conducted a case-cohort analysis within the Canadian Study of Diet, Lifestyle, and Health, a prospective cohort of 73 909 adults (39 614 women). Participants were recruited from 1992 to 1999, predominantly from three Canadian universities. We conducted a linkage with the Ontario Cancer Registry for the years 1992-2007 for the female cohort members, who resided in Ontario at the time of enrollment (n=26 024), to yield data on cancer incidence. The analytic sample was comprised of 107 incident cases and 1830 subcohort members, the latter being an age-stratified sample of the full cohort. A nonsignificant increase in the risk of endometrial cancer was associated with increased consumption of red meat [hazard ratio (HR)=1.62, 95% confidence intervals (CI)=0.86-3.08, for high vs. low intake; P trend=0.13)], processed meat (HR=1.45, 95% CI=0.80-2.61, for high vs. low intake; P trend=0.058), and all meat combined (HR=1.50, 95% CI=0.78-2.89, for high vs. low intake; P trend=0.14). No clear patterns were noted for poultry or fish. The results of this study, although based on a limited number of cases, suggest that relatively high meat intake may be associated with increased risk of endometrial cancer.

Criminality and suicide: a longitudinal Swedish cohort study

PubMed Central

Stenbacka, M; Romelsjö, A; Jokinen, J

2014-01-01

Objectives This study aimed to investigate whether violent and non-violent offending were related to elevated risk of suicide. We also investigated whether the risk was higher among those with repeated offences and how experiences of substance misuse and suicide attempt modified the relationship. Design A nationwide prospective cohort study. Setting A register study of 48 834 conscripted men in 1969/1970 in Sweden followed up during a 35-year period in official registers. Participants A birth cohort of 48 834 men who were mandatory conscripted for military service in 1969/70 at the age of 18–20 years. Possible confounders were retrieved from psychological assessments at conscription and the cohort was linked to mortality and hospitalisation and crime records from 1970 onwards. Estimates of suicide risks were calculated as HR with 95% CIs using Cox proportional regression analyses with adjustment for potential confounding by family, psychological and behavioural factors including substance use and psychiatric disorders. Results Of the total cohort, 2671 (5.5%) persons died during the follow-up period. Of these, 615 (23%) persons died due to suicide. Non-violent criminality was evident for 29% and violent criminality for 4.7% of all the participants. In the crude model, the violent offenders had nearly five times higher risk (HR=4.69, 3.56 to 6.19) to die from suicide and non-violent criminals had about two times higher risk (HR=2.08, 1.72 to 2.52). In the fully adjusted model, the HRs were still significant for suicide in the non-violent group. Conclusions Experiences of violent or non-violent criminality were associated with increased risk of suicide. Comorbidity with alcohol and substance use and psychiatric disorders modified the risk, but the suicide risk remained significantly elevated for non-violent criminals. It is crucial to identify offenders and especially repeated offenders who also suffer from alcohol or substance misuse and psychiatric illness in

Criminality and suicide: a longitudinal Swedish cohort study.

PubMed

Stenbacka, M; Romelsjö, A; Jokinen, J

2014-02-03

This study aimed to investigate whether violent and non-violent offending were related to elevated risk of suicide. We also investigated whether the risk was higher among those with repeated offences and how experiences of substance misuse and suicide attempt modified the relationship. A nationwide prospective cohort study. A register study of 48 834 conscripted men in 1969/1970 in Sweden followed up during a 35-year period in official registers. A birth cohort of 48 834 men who were mandatory conscripted for military service in 1969/70 at the age of 18-20 years. Possible confounders were retrieved from psychological assessments at conscription and the cohort was linked to mortality and hospitalisation and crime records from 1970 onwards. Estimates of suicide risks were calculated as HR with 95% CIs using Cox proportional regression analyses with adjustment for potential confounding by family, psychological and behavioural factors including substance use and psychiatric disorders. Of the total cohort, 2671 (5.5%) persons died during the follow-up period. Of these, 615 (23%) persons died due to suicide. Non-violent criminality was evident for 29% and violent criminality for 4.7% of all the participants. In the crude model, the violent offenders had nearly five times higher risk (HR=4.69, 3.56 to 6.19) to die from suicide and non-violent criminals had about two times higher risk (HR=2.08, 1.72 to 2.52). In the fully adjusted model, the HRs were still significant for suicide in the non-violent group. Experiences of violent or non-violent criminality were associated with increased risk of suicide. Comorbidity with alcohol and substance use and psychiatric disorders modified the risk, but the suicide risk remained significantly elevated for non-violent criminals. It is crucial to identify offenders and especially repeated offenders who also suffer from alcohol or substance misuse and psychiatric illness in clinical settings in order to prevent suicide.

Mysid Population Responses to Resource Limitation Differ from those Predicted by Cohort Studies

EPA Science Inventory

Effects of anthropogenic stressors on animal populations are often evaluated by assembling vital rate responses from isolated cohort studies into a single demographic model. However, models constructed from cohort studies are difficult to translate into ecological predictions be...

Multicenter AIDS Cohort Study Quantitative Coronary Plaque Progression Study: rationale and design.

PubMed

Nakanishi, Rine; Post, Wendy S; Osawa, Kazuhiro; Jayawardena, Eranthi; Kim, Michael; Sheidaee, Nasim; Nezarat, Negin; Rahmani, Sina; Kim, Nicholas; Hathiramani, Nicolai; Susarla, Shriraj; Palella, Frank; Witt, Mallory; Blaha, Michael J; Brown, Todd T; Kingsley, Lawrence; Haberlen, Sabina A; Dailing, Christopher; Budoff, Matthew J

2018-01-01

The association of HIV with coronary atherosclerosis has been established; however, the progression of coronary atherosclerosis over time among participants with HIV is not well known. The Multicenter AIDS Cohort Study Quantitative Coronary Plaque Progression Study is a large prospective multicenter study quantifying progression of coronary plaque assessed by serial coronary computed tomography angiography (CTA). HIV-infected and uninfected men who were enrolled in the Multicenter AIDS Cohort Study Cardiovascular Substudy were eligible to complete a follow-up contrast coronary CTA 3-6 years after baseline. We measured coronary plaque volume and characteristics (calcified and noncalcified plaque including fibrous, fibrous-fatty, and low attenuation) and vulnerable plaque among HIV-infected and uninfected men using semiautomated plaque software to investigate the progression of coronary atherosclerosis over time. We describe a novel, large prospective multicenter study investigating incidence, transition of characteristics, and progression in coronary atherosclerosis quantitatively assessed by serial coronary CTAs among HIV-infected and uninfected men.

Selective reporting bias of harm outcomes within studies: findings from a cohort of systematic reviews.

PubMed

Saini, Pooja; Loke, Yoon K; Gamble, Carrol; Altman, Douglas G; Williamson, Paula R; Kirkham, Jamie J

2014-11-21

To determine the extent and nature of selective non-reporting of harm outcomes in clinical studies that were eligible for inclusion in a cohort of systematic reviews. Cohort study of systematic reviews from two databases. Outcome reporting bias in trials for harm outcomes (ORBIT II) in systematic reviews from the Cochrane Library and a separate cohort of systematic reviews of adverse events. 92 systematic reviews of randomised controlled trials and non-randomised studies published in the Cochrane Library between issue 9, 2012 and issue 2, 2013 (Cochrane cohort) and 230 systematic reviews published between 1 January 2007 and 31 December 2011 in other publications, synthesising data on harm outcomes (adverse event cohort). A 13 point classification system for missing outcome data on harm was developed and applied to the studies. 86% (79/92) of reviews in the Cochrane cohort did not include full data from the main harm outcome of interest of each review for all of the eligible studies included within that review; 76% (173/230) for the adverse event cohort. Overall, the single primary harm outcome was inadequately reported in 76% (705/931) of the studies included in the 92 reviews from the Cochrane cohort and not reported in 47% (4159/8837) of the 230 reviews in the adverse event cohort. In a sample of primary studies not reporting on the single primary harm outcome in the review, scrutiny of the study publication revealed that outcome reporting bias was suspected in nearly two thirds (63%, 248/393). The number of reviews suspected of outcome reporting bias as a result of missing or partially reported harm related outcomes from at least one eligible study is high. The declaration of important harms and the quality of the reporting of harm outcomes must be improved in both primary studies and systematic reviews. © Saini et al 2014.

Study protocol title: a prospective cohort study of low back pain

PubMed Central

2013-01-01

Background Few prospective cohort studies of workplace low back pain (LBP) with quantified job physical exposure have been performed. There are few prospective epidemiological studies for LBP occupational risk factors and reported data generally have few adjustments for many personal and psychosocial factors. Methods/design A multi-center prospective cohort study has been incepted to quantify risk factors for LBP and potentially develop improved methods for designing and analyzing jobs. Due to the subjectivity of LBP, six measures of LBP are captured: 1) any LBP, 2) LBP ≥ 5/10 pain rating, 3) LBP with medication use, 4) LBP with healthcare provider visits, 5) LBP necessitating modified work duties and 6) LBP with lost work time. Workers have thus far been enrolled from 30 different employment settings in 4 diverse US states and performed widely varying work. At baseline, workers undergo laptop-administered questionnaires, structured interviews, and two standardized physical examinations to ascertain demographics, medical history, psychosocial factors, hobbies and physical activities, and current musculoskeletal disorders. All workers’ jobs are individually measured for physical factors and are videotaped. Workers are followed monthly for the development of low back pain. Changes in jobs necessitate re-measure and re-videotaping of job physical factors. The lifetime cumulative incidence of low back pain will also include those with a past history of low back pain. Incident cases will exclude prevalent cases at baseline. Statistical methods planned include survival analyses and logistic regression. Discussion Data analysis of a prospective cohort study of low back pain is underway and has successfully enrolled over 800 workers to date. PMID:23497211

Optimal design of studies of influenza transmission in households. II: comparison between cohort and case-ascertained studies.

PubMed

Klick, B; Nishiura, H; Leung, G M; Cowling, B J

2014-04-01

Both case-ascertained household studies, in which households are recruited after an 'index case' is identified, and household cohort studies, where a household is enrolled before the start of the epidemic, may be used to test and estimate the protective effect of interventions used to prevent influenza transmission. A simulation approach parameterized with empirical data from household studies was used to evaluate and compare the statistical power of four study designs: a cohort study with routine virological testing of household contacts of infected index case, a cohort study where only household contacts with acute respiratory illness (ARI) are sampled for virological testing, a case-ascertained study with routine virological testing of household contacts, and a case-ascertained study where only household contacts with ARI are sampled for virological testing. We found that a case-ascertained study with ARI-triggered testing would be the most powerful design while a cohort design only testing household contacts with ARI was the least powerful. Sensitivity analysis demonstrated that these conclusions varied by model parameters including the serial interval and the risk of influenza virus infection from outside the household.

Non-cancer morbidity among Estonian Chernobyl cleanup workers: a register-based cohort study

PubMed Central

Rahu, Kaja; Bromet, Evelyn J; Hakulinen, Timo; Auvinen, Anssi; Uusküla, Anneli; Rahu, Mati

2014-01-01

Objective To examine non-cancer morbidity in the Estonian Chernobyl cleanup workers cohort compared with the population sample with special attention to radiation-related diseases and mental health disorders. Design Register-based cohort study. Setting Estonia. Participants An exposed cohort of 3680 men (cleanup workers) and an unexposed cohort of 7631 men (population sample) were followed from 2004 to 2012 through the Population Registry and Health Insurance Fund database. Methods Morbidity in the exposed cohort compared with the unexposed controls was estimated in terms of rate ratio (RR) with 95% CIs using Poisson regression models. Results Elevated morbidity in the exposed cohort was found for diseases of the nervous system, digestive system, musculoskeletal system, ischaemic heart disease and for external causes. The most salient excess risk was observed for thyroid diseases (RR=1.69; 95% CI 1.38 to 2.07), intentional self-harm (RR=1.47; 95% CI 1.04 to 2.09) and selected alcohol-related diagnoses (RR=1.25; 95% CI 1.12 to 1.39). No increase in morbidity for stress reactions, depression, headaches or sleep disorders was detected. Conclusions No obvious excess morbidity consistent with biological effects of radiation was seen in the exposed cohort, with the possible exception of benign thyroid diseases. Increased alcohol-induced morbidity may reflect alcohol abuse, and could underlie some of the higher morbidity rates. Mental disorders in the exposed cohort were probably under-reported. The future challenge will be to study mental and physical comorbidities in the Chernobyl cleanup workers cohort. PMID:24833681

A review of published analyses of case-cohort studies and recommendations for future reporting.

PubMed

Sharp, Stephen J; Poulaliou, Manon; Thompson, Simon G; White, Ian R; Wood, Angela M

2014-01-01

The case-cohort study design combines the advantages of a cohort study with the efficiency of a nested case-control study. However, unlike more standard observational study designs, there are currently no guidelines for reporting results from case-cohort studies. Our aim was to review recent practice in reporting these studies, and develop recommendations for the future. By searching papers published in 24 major medical and epidemiological journals between January 2010 and March 2013 using PubMed, Scopus and Web of Knowledge, we identified 32 papers reporting case-cohort studies. The median subcohort sampling fraction was 4.1% (interquartile range 3.7% to 9.1%). The papers varied in their approaches to describing the numbers of individuals in the original cohort and the subcohort, presenting descriptive data, and in the level of detail provided about the statistical methods used, so it was not always possible to be sure that appropriate analyses had been conducted. Based on the findings of our review, we make recommendations about reporting of the study design, subcohort definition, numbers of participants, descriptive information and statistical methods, which could be used alongside existing STROBE guidelines for reporting observational studies.

The Targeted Antitumor Effects of C- PC/CMC-CD59sp Nanoparticles on HeLa Cells in Vitro and in Vivo

PubMed Central

Wang, Yujuan; Jiang, Liangqian; Yin, Qifeng; Liu, Huihui; Liu, Guoxiang; Zhu, Guoteng; Li, Bing

2017-01-01

The novel C-PC/CMC-CD59sp-NPs were made by carbocymethyl chitosan (CMC) loading C-phycocyanin (C-PC) with the lead of CD59 specific ligand peptide (CD59sp) for targeting, and the characteristics and targeted anti-tumor mechanism were explored in order to realize the targeted therapy of C-PC on the growth of HeLa cells both in vitro and vivo. The targeting nanoparticles were synthesized by ionic-gelation method, and the optimal condition was selected out by orthogonal analysis. The properties of nanoparticles were observed by laser particle analyzer and dynamic light scattering (DLS) and Fourier Transform Infrared Spectrometer (FTIR). The effects of nanoparticles on the proliferation of HeLa cells in vitro were assessed by MTT assay. The mice model with tumor was constructed by subcutaneous injection of HeLa cells into the left axilla of NU/NU mice. The weight of tumor and the spleen were tested. The expression quantities of cleaved caspase-3, Bcl-2 were determined by western blot and immunofluorescent staining. Results showed the morphology of the finally prepared nanoparticles was well distributed with a diameter distribution of 200±11.3 nm and zeta potential of -19.5±4.12mV. Under the guidance of CD59sp, the targeting nanoparticles could targetedly and efficiently arrive at the surface of HeLa cells, and had obvious inhibitory effect on HeLa cells proliferation both in vitro and vivo. Moreover, the nanoparticles could induce cell apoptosis by up-regulation of cleaved caspase-3 proteins expression, but down-regulation of Bcl-2 and cyclinD1 proteins. Our study provided a new idea for the research and development of marine drugs, and supplied a theoretical support for the target therapy of anticancer drug. PMID:28928892

The Targeted Antitumor Effects of C- PC/CMC-CD59sp Nanoparticles on HeLa Cells in Vitro and in Vivo.

PubMed

Wang, Yujuan; Jiang, Liangqian; Yin, Qifeng; Liu, Huihui; Liu, Guoxiang; Zhu, Guoteng; Li, Bing

2017-01-01

The novel C-PC/CMC-CD59sp-NPs were made by carbocymethyl chitosan (CMC) loading C-phycocyanin (C-PC) with the lead of CD59 specific ligand peptide (CD59sp) for targeting, and the characteristics and targeted anti-tumor mechanism were explored in order to realize the targeted therapy of C-PC on the growth of HeLa cells both in vitro and vivo . The targeting nanoparticles were synthesized by ionic-gelation method, and the optimal condition was selected out by orthogonal analysis. The properties of nanoparticles were observed by laser particle analyzer and dynamic light scattering (DLS) and Fourier Transform Infrared Spectrometer (FTIR). The effects of nanoparticles on the proliferation of HeLa cells in vitro were assessed by MTT assay. The mice model with tumor was constructed by subcutaneous injection of HeLa cells into the left axilla of NU/NU mice. The weight of tumor and the spleen were tested. The expression quantities of cleaved caspase-3, Bcl-2 were determined by western blot and immunofluorescent staining. Results showed the morphology of the finally prepared nanoparticles was well distributed with a diameter distribution of 200±11.3 nm and zeta potential of -19.5±4.12mV. Under the guidance of CD59sp, the targeting nanoparticles could targetedly and efficiently arrive at the surface of HeLa cells, and had obvious inhibitory effect on HeLa cells proliferation both in vitro and vivo. Moreover, the nanoparticles could induce cell apoptosis by up-regulation of cleaved caspase-3 proteins expression, but down-regulation of Bcl-2 and cyclinD1 proteins. Our study provided a new idea for the research and development of marine drugs, and supplied a theoretical support for the target therapy of anticancer drug.

A cohort mortality study of employees exposed to chlorinated chemicals.

PubMed

Wong, O

1988-01-01

The cohort of this historical prospective mortality study consisted of 697 male employees at a chlorination plant. A majority of the cohort was potentially exposed to benzotrichloride, benzyl chloride, benzoyl chloride, and other related chemicals. The mortality experience of the cohort was observed from 1943 through 1982. For the cohort as a whole, no statistically significant mortality excess was detected. The overall Standardized Mortality Ratio (SMR) was 100, and the SMR for all cancers combined was 122 (not significant). The respiratory cancer SMR for the cohort as a whole was 246 (7 observed vs. 2.8 expected). The excess was of borderline statistical significance, the lower 95% confidence limit being 99. Analysis by race showed that all 7 respiratory cancer deaths came from the white male employees, with an SMR of 265 (p less than 0.05). The respiratory cancer mortality excess was higher among employees in maintenance (SMR = 229) than among those in operations or production (SMR = 178). The lung cancer mortality excess among the laboratory employees was statistically significant (SMR = 1292). However, this observation should be viewed with caution, since it was based on only 2 deaths. Further analysis indicated that the respiratory cancer mortality excess was limited to the male employees with 15 or more years of employment (SMR = 379, p less than 0.05). Based on animal data as well as other epidemiologic studies, together with the internal consistency of analysis by length of employment, the data suggest an association between the chlorination process of toluene at the plant and an increased risk of respiratory cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Cohort Profile: Antiretroviral Therapy Cohort Collaboration (ART-CC)

PubMed Central

May, Margaret T; Ingle, Suzanne M; Costagliola, Dominique; Justice, Amy C; de Wolf, Frank; Cavassini, Matthias; D’Arminio Monforte, Antonella; Casabona, Jordi; Hogg, Robert S; Mocroft, Amanda; Lampe, Fiona C; Dabis, François; Fätkenheuer, Gerd; Sterling, Timothy R; del Amo, Julia; Gill, M John; Crane, Heidi M; Saag, Michael S; Guest, Jodie; Brodt, Hans-Reinhard; Sterne, Jonathan AC

2014-01-01

The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70 000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org). PMID:23599235

Challenges in translating endpoints from trials to observational cohort studies in oncology

PubMed Central

Ording, Anne Gulbech; Cronin-Fenton, Deirdre; Ehrenstein, Vera; Lash, Timothy L; Acquavella, John; Rørth, Mikael; Sørensen, Henrik Toft

2016-01-01

Clinical trials are considered the gold standard for examining drug efficacy and for approval of new drugs. Medical databases and population surveillance registries are valuable resources for post-approval observational research, which are increasingly used in studies of benefits and risk of new cancer drugs. Here, we address the challenges in translating endpoints from oncology trials to observational studies. Registry-based cohort studies can investigate real-world safety issues – including previously unrecognized concerns – by examining rare endpoints or multiple endpoints at once. In contrast to clinical trials, observational cohort studies typically do not exclude real-world patients from clinical practice, such as old and frail patients with comorbidity. The observational cohort study complements the clinical trial by examining the effectiveness of interventions applied in clinical practice and by providing evidence on long-term clinical outcomes, which are often not feasible to study in a clinical trial. Various endpoints can be included in clinical trials, such as hard endpoints, soft endpoints, surrogate endpoints, and patient-reported endpoints. Each endpoint has it strengths and limitations for use in research studies. Endpoints used in oncology trials are often not applicable in observational cohort studies which are limited by the setting of standard clinical practice and by non-standardized endpoint determination. Observational studies can be more helpful moving research forward if they restrict focus to appropriate and valid endpoints. PMID:27354827

Cohort Differences in Cognitive Aging and Terminal Decline in the Seattle Longitudinal Study

PubMed Central

Gerstorf, Denis; Ram, Nilam; Hoppmann, Christiane; Willis, Sherry L.; Schaie, K. Warner

2011-01-01

Life span researchers have long been interested in how and why fundamental aspects of human ontogeny differ between cohorts of people who have lived through different historical epochs. When examined at the same age, later born cohorts are often cognitively and physically fitter than earlier born cohorts. Less is known, however, about cohort differences in the rate of cognitive aging and if, at the very end of life, pervasive mortality-related processes overshadow and minimize cohort differences. We used data on 5 primary mental abilities from the Seattle Longitudinal Study (Schaie, 2005) to compare both age-related and mortality-related changes between earlier born cohorts (1886–1913) and later born cohorts (1914–1948). Our models covary for several individual and cohort differences in central indicators of life expectancy, education, health, and gender. Age-related growth models corroborate and extend earlier findings by documenting level differences at age 70 of up to 0.50 SD and less steep rates of cognitive aging on all abilities between 50 and 80 years of age favoring the later born cohort. In contrast, mortality-related models provide limited support for positive cohort differences. The later born cohort showed steeper mortality-related declines. We discuss possible reasons why often reported positive secular trends in age-related processes may not generalize to the vulnerable segment of the population that is close to death and suggest routes for further inquiry. PMID:21517155

Cohort profile: LIFEWORK, a prospective cohort study on occupational and environmental risk factors and health in the Netherlands.

PubMed

Reedijk, Marije; Lenters, Virissa; Slottje, Pauline; Pijpe, Anouk; Peeters, Petra H; Korevaar, Joke C; Bueno-de-Mesquita, Bas; Verschuren, W M Monique; Verheij, Robert A; Pieterson, Inka; van Leeuwen, Flora E; Rookus, Matti A; Kromhout, Hans; Vermeulen, Roel C H

2018-02-03

LIFEWORK is a large federated prospective cohort established in the Netherlands to quantify the health effects of occupational and environmental exposures. This cohort is also the Dutch contribution to the international Cohort Study of Mobile Phone Use and Health (COSMOS). In this paper, we describe the study design, ongoing data collection, baseline characteristics of participants and the repeatability of key questionnaire items. 88 466 participants were enrolled in three cohort studies in 2011-2012. Exposure information was collected by a harmonised core questionnaire, or modelled based on occupational and residential histories; domains include air pollution (eg, nitrogen dioxide (NO 2 ), particulate matter with diameter ≤2.5 µm (PM 2.5 )), noise, electromagnetic fields (EMF), mobile phone use, shift work and occupational chemical exposures. Chronic and subacute health outcomes are assessed by self-report and through linkage with health registries. Participants had a median age of 51 years at baseline (range 19-87), and the majority are female (90%), with nurses being over-represented. Median exposure levels of NO 2 , PM 2.5 , EMF from base stations and noise at the participants' home addresses at baseline were 22.9 µg/m 3 , 16.6 µg/m 3 , 0.003 mWm 2 and 53.1 dB, respectively. Twenty-two per cent of participants reported to have started using a mobile phone more than 10 years prior to baseline. Repeatability for self-reported exposures was moderate to high (weighted kappa range: 0.69-1) for a subset of participants (n=237) who completed the questionnaire twice. We are actively and passively observing participants; we plan to administer a follow-up questionnaire every 4-5 years-the first follow-up will be completed in 2018-and linkage to cause-of-death and cancer registries occurs on a (bi)annual basis. This prospective cohort offers a unique, large and rich resource for research on contemporary occupational and environmental health risks and will

Cohort profile: LIFEWORK, a prospective cohort study on occupational and environmental risk factors and health in the Netherlands

PubMed Central

Peeters, Petra H; Korevaar, Joke C; Bueno-de-Mesquita, Bas; Verschuren, W M Monique; Verheij, Robert A; Pieterson, Inka; van Leeuwen, Flora E

2018-01-01

Purpose LIFEWORK is a large federated prospective cohort established in the Netherlands to quantify the health effects of occupational and environmental exposures. This cohort is also the Dutch contribution to the international Cohort Study of Mobile Phone Use and Health (COSMOS). In this paper, we describe the study design, ongoing data collection, baseline characteristics of participants and the repeatability of key questionnaire items. Participants 88 466 participants were enrolled in three cohort studies in 2011–2012. Exposure information was collected by a harmonised core questionnaire, or modelled based on occupational and residential histories; domains include air pollution (eg, nitrogen dioxide (NO2), particulate matter with diameter ≤2.5 µm (PM2.5)), noise, electromagnetic fields (EMF), mobile phone use, shift work and occupational chemical exposures. Chronic and subacute health outcomes are assessed by self-report and through linkage with health registries. Findings to date Participants had a median age of 51 years at baseline (range 19–87), and the majority are female (90%), with nurses being over-represented. Median exposure levels of NO2, PM2.5, EMF from base stations and noise at the participants’ home addresses at baseline were 22.9 µg/m3, 16.6 µg/m3, 0.003 mWm2 and 53.1 dB, respectively. Twenty-two per cent of participants reported to have started using a mobile phone more than 10 years prior to baseline. Repeatability for self-reported exposures was moderate to high (weighted kappa range: 0.69–1) for a subset of participants (n=237) who completed the questionnaire twice. Future plans We are actively and passively observing participants; we plan to administer a follow-up questionnaire every 4–5 years—the first follow-up will be completed in 2018—and linkage to cause-of-death and cancer registries occurs on a (bi)annual basis. This prospective cohort offers a unique, large and rich resource for research on contemporary

Non-cancer morbidity among Estonian Chernobyl cleanup workers: a register-based cohort study.

PubMed

Rahu, Kaja; Bromet, Evelyn J; Hakulinen, Timo; Auvinen, Anssi; Uusküla, Anneli; Rahu, Mati

2014-05-14

To examine non-cancer morbidity in the Estonian Chernobyl cleanup workers cohort compared with the population sample with special attention to radiation-related diseases and mental health disorders. Register-based cohort study. Estonia. An exposed cohort of 3680 men (cleanup workers) and an unexposed cohort of 7631 men (population sample) were followed from 2004 to 2012 through the Population Registry and Health Insurance Fund database. Morbidity in the exposed cohort compared with the unexposed controls was estimated in terms of rate ratio (RR) with 95% CIs using Poisson regression models. Elevated morbidity in the exposed cohort was found for diseases of the nervous system, digestive system, musculoskeletal system, ischaemic heart disease and for external causes. The most salient excess risk was observed for thyroid diseases (RR=1.69; 95% CI 1.38 to 2.07), intentional self-harm (RR=1.47; 95% CI 1.04 to 2.09) and selected alcohol-related diagnoses (RR=1.25; 95% CI 1.12 to 1.39). No increase in morbidity for stress reactions, depression, headaches or sleep disorders was detected. No obvious excess morbidity consistent with biological effects of radiation was seen in the exposed cohort, with the possible exception of benign thyroid diseases. Increased alcohol-induced morbidity may reflect alcohol abuse, and could underlie some of the higher morbidity rates. Mental disorders in the exposed cohort were probably under-reported. The future challenge will be to study mental and physical comorbidities in the Chernobyl cleanup workers cohort. 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.

The Korea Nurses' Health Study: A Prospective Cohort Study.

PubMed

Kim, Oksoo; Ahn, Younjhin; Lee, Hea-Young; Jang, Hee Jung; Kim, Sue; Lee, Jung Eun; Jung, Heeja; Cho, Eunyoung; Lim, Joong-Yeon; Kim, Min-Ju; Willett, Walter C; Chavarro, Jorge E; Park, Hyun-Young

2017-08-01

The Korea Nurses' Health Study (KNHS) is a prospective cohort study of female nurses, focusing on the effects of occupational, environmental, and lifestyle risk factors on the health of Korean women. Female registered nurses aged 20-45 years and living in the Republic of Korea were invited to join the study, which began in July 2013. They were asked to complete a web-based baseline survey. The study protocols and questionnaires related to the KNHS are based on the Nurses' Health Study 3 (NHS3) in the United States, although they were modified to reflect the Korean lifestyle. Participants were asked about demographic, lifestyle factors, disease history, occupational exposure, reproductive factors, and dietary habits during their adolescence: Follow-up questionnaires were/will be completed at 6-8 month intervals after the baseline survey. If a participant became pregnant, she answered additional questionnaires containing pregnancy-related information. Among 157,569 eligible female nurses, 20,613 (13.1%) completed the web-based baseline questionnaire. The mean age of the participants was 29.4 ± 5.9 years, and more than half of them were in their 20s. Eighty-eight percent of the participants had worked night shifts as a nurse (mean, 5.3 ± 4.3 nights per month). Approximately 80% of the participants had a body mass index below 23 kg/m 2 . Gastrointestinal diseases were the most prevalent health issues (25.9%). The findings from this prospective cohort study will help to identify the effects of lifestyle-related and occupational factors on reproductive health and development of chronic diseases in Korean women.

Cohort Profile: The Hawai’i Family Study of Cognition

PubMed Central

Onoye, Jane MM; Hishinuma, Earl S; McArdle, John J; Zonderman, Alan B; Takeshita, Junji

2014-01-01

Intergenerational longitudinal studies over the lifespan provide valuable information for understanding the contexts and dynamic relations among cognition, family and health in adults and the elderly. The Hawai‘i Family Study of Cognition (HFSC), initiated in the early 1970s, included a cohort of over 6500 individuals representing over 1800 families of parents and their offspring. The HFSC gathered data on cognitive, personality, biological and other psychosocial variables, and provided novel information on the nature of cognitive abilities, especially on family issues. Some families were reassessed with short-term retesting in the 1970s. A select sample of offspring and their siblings and spouses were re-measured in the 1980s. Decades later, a 40-year follow-up of the original HFSC cohort was facilitated by the availability of contemporary tracking and tracing methods and internet-based testing. A subgroup of the original HFSC participants was re-contacted and retested on contemporary cognitive as well as socio-demographic and health measures. In this paper, we describe the original HFSC cohort and the design and methodology of the re-contact and retest studies of the HFSC, plans for expanding the re-contact and retesting, as well as directions for future research and collaborations. The Principal Investigator may be contacted for more information regarding the application, review and approval process for data access requests from qualified individuals outside the project. PMID:24639439

Cohort Profile: The Malaysian Cohort (TMC) project: a prospective study of non-communicable diseases in a multi-ethnic population

PubMed Central

Jamal, Rahman; Syed Zakaria, Syed Zulkifli; Kamaruddin, Mohd Arman; Abd Jalal, Nazihah; Ismail, Norliza; Mohd Kamil, Norkhamiwati; Abdullah, Noraidatulakma; Baharudin, Norhafizah; Hussin, Noor Hamidah; Othman, Hanita; Mahadi, Nor Muhammad

2015-01-01

The Malaysian Cohort study was initiated in 2005 by the Malaysian government. The top-down approach to this population-based cohort study ensured the allocation of sufficient funding for the project which aimed to recruit 100 000 individuals aged 35–70 years. Participants were recruited from rural and urban areas as well as from various socioeconomic groups. The main objectives of the study were to identify risk factors, to study gene-environment interaction and to discover biomarkers for the early detection of cancers and other diseases. At recruitment, a questionnaire-based interview was conducted, biophysical measurements were performed and biospecimens were collected, processed and stored. Baseline investigations included fasting blood sugar, fasting lipid profile, renal profile and full blood count. From April 2006 to the end of September 2012 we recruited a total of 106 527participants. The baseline prevalence data showed 16.6% participants with diabetes, 46.5% with hypertension, 44.9% with hypercholesterolaemia and 17.7% with obesity. The follow-up phase commenced in June 2013. This is the most comprehensive and biggest cohort study in Malaysia, and has become a valuable resource for epidemiological and biological research. For information on collaboration and also data access, investigators can contact the project leader at (rahmanj@ppukm.ukm.edu.my). PMID:24729425

Primary Sjogren's syndrome and the risk of acute pancreatitis: a nationwide cohort study.

PubMed

Chang, Chi-Ching; Chang, Yu-Sheng; Wang, Shu-Hung; Lin, Shyr-Yi; Chen, Yi-Hsuan; Chen, Jin Hua

2017-08-11

Studies on the risk of acute pancreatitis in patients with primary Sjogren's syndrome (pSS) are limited. We evaluated the effects of pSS on the risk of acute pancreatitis in a nationwide, population-based cohort in Taiwan. Population-based retrospective cohort study. We studied the claims data of the >97% Taiwan population from 2002 to 2012. We identified 9468 patients with pSS by using the catastrophic illness registry of the National Health Insurance Database in Taiwan. We also selected 37 872 controls that were randomly frequency matched by age (in 5 year bands), sex and index year from the general population. We analysed the risk of acute pancreatitis by using Cox proportional hazards regression models including sex, age and comorbidities. From 23.74 million people in the cohort, 9468 patients with pSS (87% women, mean age=55.6 years) and 37 872 controls were followed-up for 4.64 and 4.74 years, respectively. A total of 44 cases of acute pancreatitis were identified in the pSS cohort versus 105 cases in the non-pSS cohort. Multivariate Cox regression analysis indicated that the incidence rate of acute pancreatitis was significantly higher in the pSS cohort than in the non-pSS cohort (adjusted HR (aHR) 1.48, 95% CI 1.03 to 2.12). Cyclophosphamide use increased the risk of acute pancreatitis (aHR 5.27, 95% CI 1.16 to 23.86). By contrast, hydroxychloroquine reduced the risk of acute pancreatitis (aHR 0.23, 95% CI 0.09 to 0.55). This nationwide, retrospective cohort study demonstrated that the risk of acute pancreatitis was significantly higher in patients with pSS than in the general population. © 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.

Cohort profile: the Geoscience and Health Cohort Consortium (GECCO) in the Netherlands

PubMed Central

Timmermans, Erik J; Lakerveld, Jeroen; Beulens, Joline W J; Boomsma, Dorret I; Kramer, Sophia E; Oosterman, Mirjam; Willemsen, Gonneke; Stam, Mariska; Nijpels, Giel; Schuengel, Carlo; Smit, Jan H; Brunekreef, Bert; Dekkers, Jasper E C; Deeg, Dorly J H; Penninx, Brenda W J H; Huisman, Martijn

2018-01-01

Purpose In the Netherlands, a great variety of objectively measured geo-data is available, but these data are scattered and measured at varying spatial and temporal scales. The centralisation of these geo-data and the linkage of these data to individual-level data from longitudinal cohort studies enable large-scale epidemiological research on the impact of the environment on public health in the Netherlands. In the Geoscience and Health Cohort Consortium (GECCO), six large-scale and ongoing cohort studies have been enriched with a variety of existing geo-data. Here, we introduce GECCO by describing: (1) the phenotypes of the involved cohort studies, (2) the collected geo-data and their sources, (3) the methodology that was used to link the collected geo-data to individual cohort studies, (4) the similarity of commonly used geo-data between our consortium and the nationwide situation in the Netherlands and (5) the distribution of geo-data within our consortium. Participants GECCO includes participants from six prospective cohort studies (eg, 44 657 respondents (18–100 years) in 2006) and it covers all municipalities in the Netherlands. Using postal code information of the participants, geo-data on the address-level, postal code-level as well as neighbourhood-level could be linked to individual-level cohort data. Findings to date The geo-data could be successfully linked to almost all respondents of all cohort studies, with successful data-linkage rates ranging from 97.1% to 100.0% between cohort studies. The results show variability in geo-data within and across cohorts. GECCO increases power of analyses, provides opportunities for cross-checking and replication, ensures sufficient geographical variation in environmental determinants and allows for nuanced analyses on specific subgroups. Future plans GECCO offers unique opportunities for (longitudinal) studies on the complex relationships between the environment and health outcomes. For example, GECCO will be

Cohort profile: the Geoscience and Health Cohort Consortium (GECCO) in the Netherlands.

PubMed

Timmermans, Erik J; Lakerveld, Jeroen; Beulens, Joline W J; Boomsma, Dorret I; Kramer, Sophia E; Oosterman, Mirjam; Willemsen, Gonneke; Stam, Mariska; Nijpels, Giel; Schuengel, Carlo; Smit, Jan H; Brunekreef, Bert; Dekkers, Jasper E C; Deeg, Dorly J H; Penninx, Brenda W J H; Huisman, Martijn

2018-06-09

In the Netherlands, a great variety of objectively measured geo-data is available, but these data are scattered and measured at varying spatial and temporal scales. The centralisation of these geo-data and the linkage of these data to individual-level data from longitudinal cohort studies enable large-scale epidemiological research on the impact of the environment on public health in the Netherlands. In the Geoscience and Health Cohort Consortium (GECCO), six large-scale and ongoing cohort studies have been enriched with a variety of existing geo-data. Here, we introduce GECCO by describing: (1) the phenotypes of the involved cohort studies, (2) the collected geo-data and their sources, (3) the methodology that was used to link the collected geo-data to individual cohort studies, (4) the similarity of commonly used geo-data between our consortium and the nationwide situation in the Netherlands and (5) the distribution of geo-data within our consortium. GECCO includes participants from six prospective cohort studies (eg, 44 657 respondents (18-100 years) in 2006) and it covers all municipalities in the Netherlands. Using postal code information of the participants, geo-data on the address-level, postal code-level as well as neighbourhood-level could be linked to individual-level cohort data. The geo-data could be successfully linked to almost all respondents of all cohort studies, with successful data-linkage rates ranging from 97.1% to 100.0% between cohort studies. The results show variability in geo-data within and across cohorts. GECCO increases power of analyses, provides opportunities for cross-checking and replication, ensures sufficient geographical variation in environmental determinants and allows for nuanced analyses on specific subgroups. GECCO offers unique opportunities for (longitudinal) studies on the complex relationships between the environment and health outcomes. For example, GECCO will be used for further research on environmental determinants

Cohort profile: Antiretroviral Therapy Cohort Collaboration (ART-CC).

PubMed

May, Margaret T; Ingle, Suzanne M; Costagliola, Dominique; Justice, Amy C; de Wolf, Frank; Cavassini, Matthias; D'Arminio Monforte, Antonella; Casabona, Jordi; Hogg, Robert S; Mocroft, Amanda; Lampe, Fiona C; Dabis, François; Fätkenheuer, Gerd; Sterling, Timothy R; del Amo, Julia; Gill, M John; Crane, Heidi M; Saag, Michael S; Guest, Jodie; Brodt, Hans-Reinhard; Sterne, Jonathan A C

2014-06-01

The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70,000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org). Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2013; all rights reserved.

Health impact of US military service in a large population-based military cohort: findings of the Millennium Cohort Study, 2001-2008

PubMed Central

2011-01-01

Background Combat-intense, lengthy, and multiple deployments in Iraq and Afghanistan have characterized the new millennium. The US military's all-volunteer force has never been better trained and technologically equipped to engage enemy combatants in multiple theaters of operations. Nonetheless, concerns over potential lasting effects of deployment on long-term health continue to mount and are yet to be elucidated. This report outlines how findings from the first 7 years of the Millennium Cohort Study have helped to address health concerns related to military service including deployments. Methods The Millennium Cohort Study was designed in the late 1990s to address veteran and public concerns for the first time using prospectively collected health and behavioral data. Results Over 150 000 active-duty, reserve, and National Guard personnel from all service branches have enrolled, and more than 70% of the first 2 enrollment panels submitted at least 1 follow-up survey. Approximately half of the Cohort has deployed in support of operations in Iraq and Afghanistan. Conclusion The Millennium Cohort Study is providing prospective data that will guide public health policymakers for years to come by exploring associations between military exposures and important health outcomes. Strategic studies aim to identify, reduce, and prevent adverse health outcomes that may be associated with military service, including those related to deployment. PMID:21281496

Millennium Cohort Study: A Department of Defense Research Project

Science.gov Websites

Milco Logo service logos Home Start Survey About the Study FAQ Resources Endorsements Infographics Awards Press Collaboration Study Topics Update Contact Info Contact Us Memorial Day 2018 carousel panel MedicalXpress Logo UT San Diego Logo Click on logos to view content associated with the Millennium Cohort Study

A cohort mortality study of forestry workers exposed to phenoxy acid herbicides.

PubMed Central

Green, L M

1991-01-01

A cohort mortality study was undertaken of forestry workers at a public electrical utility who had worked for six months or more during 1950-82 and who were routinely exposed to herbicides including phenoxy acids. A total of 1222 men with 25 274 years at risk experienced 80 deaths. Ascertainment of vital state at the end of follow up was 95.5%. The male population of the province (Ontario) was used as the reference group. Overall, no excess mortality was found in this cohort relative to the reference population. A statistically significant increase in deaths occurred, however, due to suicide (SMR = 210, 95% confidence interval, 95% CI 105-376) for the cohort as a whole. No deaths were seen due to cancers such as soft tissue sarcoma and non-Hodgkin's lymphoma that have been cited by other authors as being associated with exposure to phenoxy acid herbicides. Although the cohort is not large, the absence of deaths due to these cancers is consistent with findings from other studies with sufficient numbers to allow examination of specific risks. The cohort is still young, however, and at the end of follow up most had not reached an age when increased incidence of cancer would normally be expected. PMID:2025588

Associations between sleep bruxism and (peri-) implant complications: a prospective cohort study

PubMed Central

Thymi, Magdalini; Visscher, Corine M; Yoshida-Kohno, Eiko; Crielaard, Wim; Wismeijer, Daniel; Lobbezoo, Frank

2017-01-01

Objectives/Aims: To describe the protocol of a prospective cohort study designed to answer the question: ‘Is sleep bruxism a risk factor for (peri-)implant complications?’. Materials and Methods: Our study is a single-centre, double-blind, prospective cohort study with a follow-up time of 2 years. Ninety-eight participants fulfilling inclusion criteria (planned treatment with implant-supported fixed suprastructure(s) and age 18 years or older) will be included. Sleep bruxism will be monitored at several time points as masticatory muscle activity during sleep by means of a portable single-channel electromyographic device. Our main outcomes are biological complications (i.e., related to peri-implant bleeding, probing depth, marginal bone height, quality of submucosal biofilm and loss of osseointegration) and technical complications (i.e., suprastructure, abutment, implant body or other). Results: The study is currently ongoing, and data are being gathered. Discussion: The results of this prospective cohort study will provide important information for clinicians treating bruxing patients with dental implants. Furthermore, it will contribute to the body of evidence related to the behaviour of dental implants and their complications under conditions of high mechanical loadings that result from sleep bruxism activity. Conclusion: The protocol of a prospective cohort study designed to investigate possible associations between sleep bruxism and (peri-) implant complications was presented. PMID:29607076

Linking exposures and health outcomes to a large population-based longitudinal study: the Millennium Cohort Study.

PubMed

Smith, Tyler C

2011-07-01

To describe current efforts and future potential for understanding long-term health of military service members by linking the Millennium Cohort Study data to exposures and health outcomes. The Millennium Cohort Study launched in 2001, before September 11 and the start of combat operations in Afghanistan and Iraq. Other substantial Department of Defense (DoD) health, personnel, and exposure databases are maintained in electronic form and may be linked by personal identifiers. More than 150,000 consenting members comprise the Millennium Cohort from all services, and include active duty, Reserve, and National Guard current and past members, and represent demographic, occupational, military, and health characteristics of the U.S. military. These prospective data offer symptom assessment, behavioral health, and self-reported exposures that may complement and fill gaps in capability presented by other DoD electronic health and exposure data. In conjunction with Millennium Cohort survey data, prospective individual-level exposure and health outcome assessment is crucial to understand and quantify any long-term health outcomes potentially associated with unique military occupational exposures.

A comparison of the results of prospective and retrospective cohort studies in the field of digestive surgery.

PubMed

Ukai, Tomohiko; Shikata, Satoru; Nakayama, Takeo; Takemura, Yousuke C

2017-07-01

We compared the results of prospective and retrospective cohort studies in the field of digestive surgery to clarify whether the results of prospective cohort studies were more similar to those of randomized controlled trials (RCTs). We conducted a secondary analysis of the results to compare the results of RCTs with those of cohort studies in meta-analyses of 18 digestive surgical topics. The data from the prospective and retrospective cohort studies were combined. The summary estimates of each design were compared with those of RCTs. We used the Z score to investigate discrepancies. Twenty-nine outcomes of 11 topics were investigated in 289 cohort studies (prospective, n = 69; retrospective, n = 220). These were compared with the outcomes of 123 RCTs. In comparison to retrospective studies, the summary estimates of the prospective cohort studies were more similar to those of the RCTs [19/29 (prospective) vs. 10/29 (retrospective), P = 0.035). Five of the 29 outcomes of prospective studies and 6 of 29 outcomes of retrospective studies (P = 0.99) showed significant discrepancies in comparison to RCTs. In the digestive surgical field, the results of prospective cohort studies tended to be more similar to those of RCTs than retrospective studies; however, there were no significant discrepancies between the two types of cohort study.

Physicochemical Investigation of 2,4,5-Trimethoxybenzylidene Propanedinitrile (TMPN) Dye as Fluorescence off-on Probe for Critical Micelle Concentration (CMC) of SDS and CTAB.

PubMed

Khan, Salman A; Asiri, Abdullah M

2015-11-01

2,4,5-trimethoxybenzylidene propanedinitrile (TMPN) was synthesized by Knoevenagel condensation. Structure of the TMPN was conformed by the elemental analysis and EI-MS, FT-IR, (1)H-NMR, (13)C-NMR spectroscopy. Absorbance and emission spectrum of the TMPN was studied in different solvent provide that TMPN is good absorbent and emission red shift in absorbance and emission spectra as polarity of the solvents increase. Photophysical properties including, oscillator strength, extinction coefficient, transition dipole moment, stokes shift and fluorescence quantum yield were investigated in order to investigate the physicochemical behaviors of TMPN. Dye undergoes solubilization in different micelles and may be used as a probe to determine the critical micelle concentration (CMC) of SDS and CTAB.

Chocolate consumption and risk of atrial fibrillation: Two cohort studies and a meta-analysis.

PubMed

Larsson, Susanna C; Drca, Nikola; Jensen-Urstad, Mats; Wolk, Alicja

2018-01-01

Chocolate consumption has been inconsistently associated with risk of atrial fibrillation (AF). We investigated the association between chocolate consumption and risk of AF in Swedish adults from two cohort studies and conducted a meta-analysis to summarize available evidence from cohort studies on this topic. Our study population comprised 40,009 men from the Cohort of Swedish Men and 32,486 women from the Swedish Mammography Cohort. Incident AF cases were ascertained through linkage with the Swedish National Patient Register. Published cohort studies of chocolate consumption in relation to risk of AF were identified by a PubMed search through September 14, 2017. During a mean follow-up of 14.6 years, AF was diagnosed in 9978 Swedish men and women. Compared with non-consumers, the multivariable hazard ratio of AF for those in the highest category of chocolate consumption (≥3-4 servings/week) was 0.96 (95% CI 0.88-1.04). In a random-effects meta-analysis of 5 cohort studies, including 180,454 participants and 16,356 AF cases, the hazard ratios of AF were 0.97 (95% CI 0.94-1.01) per 2 servings/week increase in chocolate consumption and 0.96 (95% CI 0.90-1.03) for the highest versus lowest category of chocolate consumption. Available data provide no evidence of an association of chocolate consumption with risk of AF. Copyright © 2017 Elsevier Inc. All rights reserved.

Trends in Dementia Incidence in a Birth Cohort Analysis of the Einstein Aging Study.

PubMed

Derby, Carol A; Katz, Mindy J; Lipton, Richard B; Hall, Charles B

2017-11-01

Trends in dementia incidence rates have important implications for planning and prevention. To better understand incidence trends over time requires separation of age and cohort effects, and few prior studies have used this approach. To examine trends in dementia incidence and concomitant trends in cardiovascular comorbidities among individuals aged 70 years or older who were enrolled in the Einstein Aging Study between 1993 and 2015. In this birth cohort analysis of all-cause dementia incidence in persons enrolled in the Einstein Aging Study from October 20, 1993, through November 17, 2015, a systematically recruited, population-based sample of 1348 participants from Bronx County, New York, who were 70 years or older without dementia at enrollment and at least one annual follow-up was studied. Poisson regression was used to model dementia incidence as a function of age, sex, educational level, race, and birth cohort, with profile likelihood used to identify the timing of significant increases or decreases in incidence. Birth year and age. Incident dementia defined by consensus case conference based on annual, standardized neuropsychological and neurologic examination findings, using criteria from the DSM-IV. Among 1348 individuals (mean [SD] baseline age, 78.5 [5.4] years; 830 [61.6%] female; 915 [67.9%] non-Hispanic white), 150 incident dementia cases developed during 5932 person-years (mean [SD] follow-up, 4.4 [3.4] years). Dementia incidence decreased in successive birth cohorts. Incidence per 100 person-years was 5.09 in birth cohorts before 1920, 3.11 in the 1920 through 1924 birth cohorts, 1.73 in the 1925 through 1929 birth cohorts, and 0.23 in cohorts born after 1929. Change point analyses identified a significant decrease in dementia incidence among those born after July 1929 (95% CI, June 1929 to January 1930). The relative rate for birth cohorts before July 1929 vs after was 0.13 (95% CI, 0.04-0.41). Prevalence of stroke and myocardial infarction

Cohort study of atypical pressure ulcers development.

PubMed

Jaul, Efraim

2014-12-01

Atypical pressure ulcers (APU) are distinguished from common pressure ulcers (PU) with both unusual location and different aetiology. The occurrence and attempts to characterise APU remain unrecognised. The purpose of this cohort study was to analyse the occurrence of atypical location and the circumstances of the causation, and draw attention to the prevention and treatment by a multidisciplinary team. The cohort study spanned three and a half years totalling 174 patients. The unit incorporates two weekly combined staff meetings. One concentrates on wound assessment with treatment decisions made by the physician and nurse, and the other, a multidisciplinary team reviewing all patients and coordinating treatment. The main finding of this study identified APU occurrence rate of 21% within acquired PU over a three and a half year period. Severe spasticity constituted the largest group in this study and the most difficult to cure wounds, located in medial aspects of knees, elbows and palms. Medical devices caused the second largest occurrence of atypical wounds, located in the nape of the neck, penis and nostrils. Bony deformities were the third recognisable atypical wound group located in shoulder blades and upper spine. These three categories are definable and time observable. APU are important to be recognisable, and can be healed as well as being prevented. The prominent role of the multidisciplinary team is primary in identification, prevention and treatment. © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Cohort Profile: The Malaysian Cohort (TMC) project: a prospective study of non-communicable diseases in a multi-ethnic population.

PubMed

Jamal, Rahman; Syed Zakaria, Syed Zulkifli; Kamaruddin, Mohd Arman; Abd Jalal, Nazihah; Ismail, Norliza; Mohd Kamil, Norkhamiwati; Abdullah, Noraidatulakma; Baharudin, Norhafizah; Hussin, Noor Hamidah; Othman, Hanita; Mahadi, Nor Muhammad

2015-04-01

The Malaysian Cohort study was initiated in 2005 by the Malaysian government. The top-down approach to this population-based cohort study ensured the allocation of sufficient funding for the project which aimed to recruit 100,000 individuals aged 35-70 years. Participants were recruited from rural and urban areas as well as from various socioeconomic groups. The main objectives of the study were to identify risk factors, to study gene-environment interaction and to discover biomarkers for the early detection of cancers and other diseases. At recruitment, a questionnaire-based interview was conducted, biophysical measurements were performed and biospecimens were collected, processed and stored. Baseline investigations included fasting blood sugar, fasting lipid profile, renal profile and full blood count. From April 2006 to the end of September 2012 we recruited a total of 106,527 participants. The baseline prevalence data showed 16.6% participants with diabetes, 46.5% with hypertension, 44.9% with hypercholesterolaemia and 17.7% with obesity. The follow-up phase commenced in June 2013. This is the most comprehensive and biggest cohort study in Malaysia, and has become a valuable resource for epidemiological and biological research. For information on collaboration and also data access, investigators can contact the project leader at (rahmanj@ppukm.ukm.edu.my). © The Author 2014. Published by Oxford University Press on behalf of the International Epidemiological Association.

Current practice patterns in conservative thumb CMC joint care: survey results.

PubMed

O'Brien, Virginia H; McGaha, Jamie L

2014-01-01

Cross-sectional descriptive survey Best practice for conservative clinical care pathways is not well outlined in the literature for patients with thumb carpometacarpal joint (CMCJ) pain. This self-report survey investigated the current practice patterns of assessments and conservative interventions for the painful thumb CMCJ among hand therapists. An online survey was distributed to members of the American Society of Hand Therapists (ASHT). Questions were included about evaluation measures and intervention techniques used for this population. A descriptive analysis was completed of the results. A total of 23.5% of the ASHT membership responded to the survey. Results were categorized using the International Classification of Functioning and Disability domains as a framework. The survey results report varying use of evaluation measures, therapeutic interventions, including orthotic fabrication, joint protection and patient education all therapeutic interventional techniques, and modalities. Therapists use a comprehensive array of evaluation measures and interventions for body functions and structures in the care of thumb CMC pain. In contrast, more consistent use is needed of psychometrically-sound functional outcome measures that show change in activities and participation. This survey highlights areas to employ current evidence, as well as, future research should address environmental factors and personal factors for this population Not applicable. Copyright © 2014 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

The Sister Study Cohort: Baseline Methods and Participant Characteristics

PubMed Central

Hodgson, M. Elizabeth; Deming-Halverson, Sandra L.; Juras, Paula S.; D’Aloisio, Aimee A.; Suarez, Lourdes M.; Kleeberger, Cynthia A.; Shore, David L.; DeRoo, Lisa A.; Taylor, Jack A.; Weinberg, Clarice R.

2017-01-01

Background: The Sister Study was designed to address gaps in the study of environment and breast cancer by taking advantage of more frequent breast cancer diagnoses among women with a sister history of breast cancer and the presumed enrichment of shared environmental and genetic exposures. Objective: The Sister Study sought a large cohort of women never diagnosed with breast cancer but who had a sister (full or half) diagnosed with breast cancer. Methods: A multifaceted national effort employed novel strategies to recruit a diverse cohort, and collected biological and environmental samples and extensive data on potential breast cancer risk factors. Results: The Sister Study enrolled 50,884 U.S. and Puerto Rican women 35–74y of age (median 56 y). Although the majority were non-Hispanic white, well educated, and economically well off, substantial numbers of harder-to-recruit women also enrolled (race/ethnicity other than non-Hispanic white: 16%; no college degree: 35%; household income <$50,000: 26%). Although all had a biologic sister with breast cancer, 16.5% had average or lower risk of breast cancer according to the Breast Cancer Risk Assessment Tool (Gail score). Most were postmenopausal (66%), parous with a first full-term pregnancy <30y of age (79%), never-smokers (56%) with body mass indexes (BMIs) of <29.9 kg/m2 (70%). Few (5%) reported any cancer prior to enrollment. Conclusions: The Sister Study is a unique cohort designed to efficiently study environmental and genetic risk factors for breast cancer. Extensive exposure data over the life-course and baseline specimens provide important opportunities for studying breast cancer and other health outcomes in women. Collaborations are welcome. https://doi.org/10.1289/EHP1923 PMID:29373861

Performance of the disease risk score in a cohort study with policy-induced selection bias.

PubMed

Tadrous, Mina; Mamdani, Muhammad M; Juurlink, David N; Krahn, Murray D; Lévesque, Linda E; Cadarette, Suzanne M

2015-11-01

To examine the performance of the disease risk score (DRS) in a cohort study with evidence of policy-induced selection bias. We examined two cohorts of new users of bisphosphonates. Estimates for 1-year hip fracture rates between agents using DRS, exposure propensity scores and traditional multivariable analysis were compared. The results for the cohort with no evidence of policy-induced selection bias showed little variation across analyses (-4.1-2.0%). Analysis of the cohort with evidence of policy-induced selection bias showed greater variation (-13.5-8.1%), with the greatest difference seen with DRS analyses. Our findings suggest that caution may be warranted when using DRS methods in cohort studies with policy-induced selection bias, further research is needed.

[Assessing incident cardiovascular and metabolic diseases in epidemiological cohort studies in Germany].

PubMed

Herrmann, Wolfram J; Weikert, Cornelia; Bergmann, Manuela; Boeing, Heiner; Katzke, Verena A; Kaaks, Rudolf; Tiller, Daniel; Greiser, Karin Halina; Heier, Margit; Meisinger, Christa; Schmidt, Carsten Oliver; Neuhauser, Hannelore; Heidemann, Christin; Jünger, Claus; Wild, Philipp S; Schramm, Sara Helena; Jöckel, Karl-Heinz; Dörr, Marcus; Pischon, Tobias

2018-04-01

Cardiovascular and metabolic diseases are a major cause of mortality and loss of quality of life in Germany. Research into risk factors of these diseases requires large population-based cohort studies. Complete and accurate assessment of the incidence of cardiovascular and metabolic diseases is a key element for valid interpretation of the results from such studies. Our aim was to identify population-based cohort studies with incidence of cardiovascular and metabolic diseases in Germany and to summarize their methods for assessment and classification of disease endpoints, including myocardial infarction, type 2 diabetes, stroke, heart failure, and arterial hypertension. Within the framework of a workshop, representatives of the ascertained population-based cohort studies in Germany with incidence of cardiovascular or metabolic diseases were invited to present and to systematically provide information on their methods of endpoint identification. We identified eight studies from different regions in Germany with a total of 100,571 participants, aged 18-83 years at baseline. Self-reporting by study participants is the major source for further inquiries to assess disease endpoints in these studies. Most studies use additional data sources to verify the incidence of diseases, such as documents provided by the treating physician or hospital. Our results highlight the central role of self-reporting and the efforts associated with identification and verification of disease endpoints in cohort studies. They also provide a basis for future population-based studies that aim for standardized assessment of the incidence of cardiovascular and metabolic diseases.

Cohort profile: the QSkin Sun and Health Study.

PubMed

Olsen, Catherine M; Green, Adèle C; Neale, Rachel E; Webb, Penelope M; Cicero, Rebekah A; Jackman, Lea M; O'Brien, Suzanne M; Perry, Susan L; Ranieri, Barbara A; Whiteman, David C

2012-08-01

The QSkin Sun and Health Study comprises a cohort of 43 794 men and women aged 40-69 years randomly sampled from the population of Queensland, Australia in 2011. The cohort was established to study the development of skin cancer and melanoma in the population with the highest reported incidence of these diseases in the world. At baseline, besides demographic items and general medical history, information about standard pigmentary characteristics (including hair and eye colour, freckling tendency, tanning ability and propensity to sunburn), past and recent history of sun exposure and sunburns, sun protection behaviours, use of tanning beds and history of skin cancer was collected by self-completed questionnaire. Participants have given their consent for data linkage to the universal national health insurance scheme and for linkage to cancer registries and pathology databases, thus ensuring complete ascertainment of all future skin cancer and melanoma occurrences and medical treatments and other cancer events. Linkage to these registers will occur at predetermined intervals. Approval to access QSkin data can be obtained on application to the study investigators and submission of a formal research plan that has previous approval from the human research ethics committee of the applicant's institution.

Selection bias and patterns of confounding in cohort studies: the case of the NINFEA web-based birth cohort.

PubMed

Pizzi, Costanza; De Stavola, Bianca L; Pearce, Neil; Lazzarato, Fulvio; Ghiotti, Paola; Merletti, Franco; Richiardi, Lorenzo

2012-11-01

Several studies have examined the effects of sample selection on the exposure-outcome association estimates in cohort studies, but the reasons why this selection may induce bias have not been fully explored. To investigate how sample selection of the web-based NINFEA birth cohort may change the confounding patterns present in the source population. The characteristics of the NINFEA participants (n=1105) were compared with those of the wider source population-the Piedmont Birth Registry (PBR)-(n=36 092), and the association of two exposures (parity and educational level) with two outcomes (low birth weight and birth by caesarean section), while controlling for other risk factors, was studied. Specifically the associations among measured risk factors within each dataset were examined and the exposure-outcome estimates compared in terms of relative ORs. The associations of educational level with the other risk factors (alcohol consumption, folic acid intake, maternal age, pregnancy weight gain, previous miscarriages) partly differed between PBR and NINFEA. This was not observed for parity. Overall, the exposure-outcome estimates derived from NINFEA only differed moderately from those obtained in PBR, with relative ORs ranging between 0.74 and 1.03. Sample selection in cohort studies may alter the confounding patterns originally present in the general population. However, this does not necessarily introduce selection bias in the exposure-outcome estimates, as sample selection may reduce some of the residual confounding present in the general population.

Feasibility of a cohort study on health risks caused by occupational exposure to radiofrequency electromagnetic fields

PubMed Central

2009-01-01

Background The aim of this study was to examine the feasibility of performing a cohort study on health risks from occupational exposure to radiofrequency electromagnetic fields (RF-EMF) in Germany. Methods A set of criteria was developed to evaluate the feasibility of such a cohort study. The criteria aimed at conditions of exposure and exposure assessment (level, duration, preferably on an individual basis), the possibility to assemble a cohort and the feasibility of ascertaining various disease endpoints. Results Twenty occupational settings with workers potentially exposed to RF-EMF and, in addition, a cohort of amateur radio operators were considered. Based on expert ratings, literature reviews and our set of predefined criteria, three of the cohorts were identified as promising for further evaluation: the personnel (technicians) of medium/short wave broadcasting stations, amateur radio operators, and workers on dielectric heat sealers. After further analyses, the cohort of workers on dielectric heat sealers seems not to be feasible due to the small number of exposed workers available and to the difficulty of assessing exposure (exposure depends heavily on the respective working process and mixture of exposures, e.g. plastic vapours), although exposure was highest in this occupational setting. The advantage of the cohort of amateur radio operators was the large number of persons it includes, while the advantage of the cohort of personnel working at broadcasting stations was the quality of retrospective exposure assessment. However, in the cohort of amateur radio operators the exposure assessment was limited, and the cohort of technicians was hampered by the small number of persons working in this profession. Conclusion The majority of occupational groups exposed to RF-EMF are not practicable for setting up an occupational cohort study due to the small numbers of exposed subjects or due to exposure levels being only marginally higher than those of the general

Transport of carboxymethyl cellulose stabilized nanoscale zerovalent iron in porous media, an experimental and modeling study

NASA Astrophysics Data System (ADS)

Sleep, Brent; Mondal, Pulin; Furbacher, Paul; Cui, Ziteng; Krol, Magdalena

2015-04-01

Nano-scale zero valent iron (nZVI) is capable of reacting with a wide variety of groundwater contaminants. Therefore, during the last decade nZVI has received significant attention for application in subsurface remediation, particularly for sites contaminated with chlorinated compounds and heavy metals. However, due to agglomeration of the nZVI, delivery into the contaminated subsurface zones is challenging. Polymer stabilization of nZVI can enhance the mobility of the iron particles in the subsurface. In this study, a set of laboratory-scale transport experiments and numerical simulations were performed to evaluate carboxymethyl cellulose (CMC) polymer stabilized nZVI transport in porous media. Experiments were conducted in a two-dimensional water-saturated lab-scale glass-walled sandbox, uniformly packed with silica sand, to identify the effects of water specific discharge and CMC concentration on nZVI transport. Experiments were also performed using Lissamine Green B (LGB) dye as a non-reactive tracer to characterize the sand media. The CMC stabilized nZVI was synthesized freshly at a concentration of 1000 mg/L before each transport experiment. The synthesized CMC-nZVI mixture was characterized using transmission electron microscopy, dynamic light scattering, and UV-visual spectrophotometry. The movement of the LGB dye and nZVI in the sandbox during the experiments was monitored using time-lapsed images captured using a light source and a dark box. The transport of LGB, CMC, and CMC-nZVI was evaluated through analysis of the breakthrough curves at the outlet and the retained nZVI in the sandbox. The LGB, CMC, and nZVI transport was also modeled using a multiphase flow and transport model considering LGB and CMC as solutes, and nZVI as a colloid. Analysis of the breakthrough data showed that the mass recovery of LGB and CMC was greater than 95 % indicating conservative transport in silica sand. However, the mean residence time of CMC was significantly higher than

Cohort profile: cerebral palsy in the Norwegian and Danish birth cohorts (MOBAND-CP).

PubMed

Tollånes, Mette C; Strandberg-Larsen, Katrine; Forthun, Ingeborg; Petersen, Tanja Gram; Moster, Dag; Andersen, Anne-Marie Nybo; Stoltenberg, Camilla; Olsen, Jørn; Wilcox, Allen J

2016-09-02

The purpose of MOthers and BAbies in Norway and Denmark cerebral palsy (MOBAND-CP) was to study CP aetiology in a prospective design. MOBAND-CP is a cohort of more than 210 000 children, created as a collaboration between the world's two largest pregnancy cohorts-the Norwegian Mother and Child Cohort study (MoBa) and the Danish National Birth Cohort. MOBAND-CP includes maternal interview/questionnaire data collected during pregnancy and follow-up, plus linked information from national health registries. Initial harmonisation of data from the 2 cohorts has created 140 variables for children and their mothers. In the MOBAND-CP cohort, 438 children with CP have been identified through record linkage with validated national registries, providing by far the largest such sample with prospectively collected detailed pregnancy data. Several studies investigating various hypotheses regarding CP aetiology are currently on-going. Additional data can be harmonised as necessary to meet requirements of new projects. Biological specimens collected during pregnancy and at delivery are potentially available for assay, as are results from assays conducted on these specimens for other projects. The study size allows consideration of CP subtypes, which is rare in aetiological studies of CP. In addition, MOBAND-CP provides a platform within the context of a merged birth cohort of exceptional size that could, after appropriate permissions have been sought, be used for cohort and case-cohort studies of other relatively rare health conditions of infants and children. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

DRINKING WATER ARSENIC IN UTAH: A COHORT MORTALITY STUDY

EPA Science Inventory

The association of drinking water arsenic and mortality outcome was investigated in a cohort of residents from Millard County, Utah. Median drinking water arsenic concentrations for selected study towns ranged from 14 to 166 ppb and were from public and private samples collected ...

Reliability and Confidence Interval Analysis of a CMC Turbine Stator Vane

NASA Technical Reports Server (NTRS)

Murthy, Pappu L. N.; Gyekenyesi, John P.; Mital, Subodh K.

2008-01-01

High temperature ceramic matrix composites (CMC) are being explored as viable candidate materials for hot section gas turbine components. These advanced composites can potentially lead to reduced weight, enable higher operating temperatures requiring less cooling and thus leading to increased engine efficiencies. However, these materials are brittle and show degradation with time at high operating temperatures due to creep as well as cyclic mechanical and thermal loads. In addition, these materials are heterogeneous in their make-up and various factors affect their properties in a specific design environment. Most of these advanced composites involve two- and three-dimensional fiber architectures and require a complex multi-step high temperature processing. Since there are uncertainties associated with each of these in addition to the variability in the constituent material properties, the observed behavior of composite materials exhibits scatter. Traditional material failure analyses employing a deterministic approach, where failure is assumed to occur when some allowable stress level or equivalent stress is exceeded, are not adequate for brittle material component design. Such phenomenological failure theories are reasonably successful when applied to ductile materials such as metals. Analysis of failure in structural components is governed by the observed scatter in strength, stiffness and loading conditions. In such situations, statistical design approaches must be used. Accounting for these phenomena requires a change in philosophy on the design engineer s part that leads to a reduced focus on the use of safety factors in favor of reliability analyses. The reliability approach demands that the design engineer must tolerate a finite risk of unacceptable performance. This risk of unacceptable performance is identified as a component's probability of failure (or alternatively, component reliability). The primary concern of the engineer is minimizing this risk in

Immobilized Kluyveromyces marxianus cells in carboxymethyl cellulose for production of ethanol from cheese whey: experimental and kinetic studies.

PubMed

Roohina, Fatemeh; Mohammadi, Maedeh; Najafpour, Ghasem D

2016-09-01

Cheese whey fermentation to ethanol using immobilized Kluyveromyces marxianus cells was investigated in batch and continuous operation. In batch fermentation, the yeast cells were immobilized in carboxymethyl cellulose (CMC) polymer and also synthesized graft copolymer of CMC with N-vinyl-2-pyrrolidone, denoted as CMC-g-PVP, and the efficiency of the two developed cell entrapped beads for lactose fermentation to ethanol was examined. The yeast cells immobilized in CMC-g-PVP performed slightly better than CMC with ethanol production yields of 0.52 and 0.49 g ethanol/g lactose, respectively. The effect of supplementation of cheese whey with lactose (42, 70, 100 and 150 g/l) on fermentative performance of K. marxianus immobilized in CMC beads was considered and the results were used for kinetic studies. The first order reaction model was suitable to describe the kinetics of substrate utilization and modified Gompertz model was quite successful to predict the ethanol production. For continuous ethanol fermentation, a packed-bed immobilized cell reactor (ICR) was operated at several hydraulic retention times; HRTs of 11, 15 and 30 h. At the HRT of 30 h, the ethanol production yield using CMC beads was 0.49 g/g which implies that 91.07 % of the theoretical yield was achieved.

Design and Conduct of an Internet-Based Preconception Cohort Study in North America: Pregnancy Study Online.

PubMed

Wise, Lauren A; Rothman, Kenneth J; Mikkelsen, Ellen M; Stanford, Joseph B; Wesselink, Amelia K; McKinnon, Craig; Gruschow, Siobhan M; Horgan, Casie E; Wiley, Aleta S; Hahn, Kristen A; Sørensen, Henrik Toft; Hatch, Elizabeth E

2015-07-01

We launched the Boston University Pregnancy Study Online (PRESTO) to assess the feasibility of carrying out an Internet-based preconception cohort study in the US and Canada. We recruited female participants age 21-45 and their male partners through Internet advertisements, word of mouth, and flyers. Female participants were randomised with 50% probability to receive a subscription to FertilityFriend.com (FF), a web-based programme that collects real-time data on menstrual characteristics. We compared recruitment methods within PRESTO, assessed the cost-efficiency of PRESTO relative to its Danish counterpart (Snart-Gravid), and validated retrospectively reported date of last menstrual period (LMP) against the FF data. After 99 weeks of recruitment (2013-15), 2421 women enrolled; 1384 (57%) invited their male partners to participate, of whom 693 (50%) enrolled. Baseline characteristics were balanced across randomisation groups. Cohort retention was similar among those randomised vs. not randomised to FF (84% vs. 81%). At study enrollment, 56%, 22%, and 22% couples had been trying to conceive for < 3, 3-5, and ≥ 6 months, respectively. The cost per subject enrolled was $146 (2013 US$), which was similar to our companion Danish study and half that of a traditional cohort study. Among FF users who conceived, > 97% reported their LMP on the PRESTO questionnaire within 1 day of the LMP recorded via FF. Use of the Internet as a method of recruitment and follow-up in a North American preconception cohort study was feasible and cost-effective. © 2015 John Wiley & Sons Ltd.

Vdrive Evaluation of Remote Steering and Testing in Lasso Electrophysiology Procedures Study: The VERSATILE Study in Atrial Fibrillation Ablation.

PubMed

Nölker, Georg; Schwagten, Bruno; Deville, J Brian; Burkhardt, J David; Horton, Rodney P; Sha, Qun; Tomassoni, Gery

2016-03-01

Circular mapping catheters (CMC) are an essential tool in most atrial fibrillation ablation procedures. The Vdrive™ with V-Loop™ system enables a physician to remotely manipulate a CMC during electrophysiology studies. Our aim was to compare the clinical performance of the system to conventional CMC navigation according to efficiency and safety endpoints. A total of 120 patients scheduled to undergo a CMC study followed by pulmonary vein isolation (PVI) were included. Treatment allocation was randomized 2:1, remote navigation:manual navigation. The primary effectiveness endpoint was assessed based on both successful navigation to the targeted pulmonary vein (PV) and successful recording of PV electrograms. All PVs were treated independently within and between patients. The primary safety endpoint was assessed based on the occurrence of major adverse events (MAEs) through seven days after the study procedure. Primary effectiveness endpoints were achieved in 295/302 PVs in the Vdrive arm (97.7%) and 167/167 PVs in the manual arm (100%). Effectiveness analysis indicates Vdrive non-inferiority (pnon-inferiority = 0.0405; δ = -0.05) per the Cochran-Mantel-Haenszel test adjusted for PV correlation. Five MAEs related to the ablation procedure occurred (three in the Vdrive arm-3.9%; two in the manual arm-2.33%). No device-related MAEs were observed; safety analysis indicates Vdrive non-inferiority (pnon-inferiority = 0.0441; δ = 0.07) per the normal Z test. Remote navigation of a CMC is equivalent to manual in PVI in terms of safety and effectiveness. This allows for single-operator procedures in conjunction with a magnetically guided ablation catheter. © 2016 Wiley Periodicals, Inc.

Developing and Refining the Taiwan Birth Cohort Study (TBCS): Five Years of Experience

ERIC Educational Resources Information Center

Lung, For-Wey; Chiang, Tung-Liang; Lin, Shio-Jean; Shu, Bih-Ching; Lee, Meng-Chih

2011-01-01

The Taiwan Birth Cohort Study (TBCS) is the first nationwide birth cohort database in Asia designed to establish national norms of children's development. Several challenges during database development and data analysis were identified. Challenges include sampling methods, instrument development and statistical approach to missing data. The…

Nordic registry-based cohort studies: Possibilities and pitfalls when combining Nordic registry data.

PubMed

Maret-Ouda, John; Tao, Wenjing; Wahlin, Karl; Lagergren, Jesper

2017-07-01

All five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) have nationwide registries with similar data structure and validity, as well as personal identity numbers enabling linkage between registries. These resources provide opportunities for medical research that is based on large registry-based cohort studies with long and complete follow-up. This review describes practical aspects, opportunities and challenges encountered when setting up all-Nordic registry-based cohort studies. Relevant articles describing registries often used for medical research in the Nordic countries were retrieved. Further, our experiences of conducting this type of study, including planning, acquiring permissions, data retrieval and data cleaning and handling, and the possibilities and challenges we have encountered are described. Combining data from the Nordic countries makes it possible to create large and powerful cohorts. The main challenges include obtaining all permissions within each country, usually in the local language, and retrieving the data. These challenges emphasise the importance of having experienced collaborators within each country. Following the acquisition of data, data management requires the understanding of the differences between the variables to be used in the various countries. A concern is the long time required between initiation and completion. Nationwide Nordic registries can be combined into cohorts with high validity and statistical power, but the considerable expertise, workload and time required to complete such cohorts should not be underestimated.

Lifestyle in Multiple Myeloma - a longitudinal cohort study protocol.

PubMed

Heinrich, M; Fisher, A; Paton, B; McCourt, O; Beeken, R J; Hackshaw, A; Wardle, J; Yong, K

2016-07-04

Deterioration in bone health is one of the presenting symptoms of Multiple Myeloma (MM), a cancer of plasma cells. As a consequence of this condition, patients suffer bone pain and bone damage and report cancer-related fatigue, resulting in deterioration in their quality of life. Evidence in patients with solid tumours shows promise for the positive effects of physical activity on quality of life. However, in the case of patients with MM a better understanding of the association between physical fitness and quality of life factors is still required. Therefore, this cohort study aims to objectively and longitudinally assess activity and fitness levels in patients with MM in order to explore their role in bone health, fatigue and quality of life for this patient population. The study is a prospective cohort study of MM patients in remission to assess physical activity, fatigue and bone health. Clinical markers of health, self-reported measures of psychological and physical well-being, and lifestyle behaviours are assessed at baseline, 3, 6 and 12 months. At each time point, patients complete cardiopulmonary exercise testing (CPET) along with a series of objective tests to assess physical fitness (eg accelerometry) and a number of self-report measures. A complementary qualitative study will be carried out in order to explore patients' desire for lifestyle advice and when in their cancer journey they deem such advice to be useful. This study will be the first to prospectively and longitudinally explore associations between physical fitness and well-being, bone health, and fatigue (along with a number of other physical and clinical outcomes) in a cohort of patients with MM with the use of objective measures. The findings will also help to identify time points within the MM pathway at which physical activity interventions may be introduced for maximum benefit.

Self-aggregation behavior of synthetic amphiphile derived from triazolylbenzoic acid: CMC and phase transition

NASA Astrophysics Data System (ADS)

Tajuddin, Hairul Anuar; Idris, Tarmezee; Zul, Nurul Faiezin; Sadidarto, Ahmad Bayhaki; Abdullah, Zanariah; Ahmad, Noraini

2017-12-01

An anionic surfactant with intention to mimic the natural fatty acids with highly conjugated component, has been synthesized and analyzed by using NMR, FTIR and MS. The polar head group of the structure was linked to the hydrophobic tail, through triazolyl moiety that was formed from the Cu(I) cycloaddition between an azidobenzoic acid and an acetylene. The critical micellar concentration (cmc) of the surfactant was determined at 0.1 mM by measuring its conductivity at a constant pH, consistent with the UV-Visible absorption. Phase transitions of the surfactant were then observed, by gradually decreasing the pH from 10 to 7. There were two stages of phase transitions observed at pH 8.9 and 7.6 upon titration, suggesting the transition from smaller to larger size of the aggregation structures. The results indicate that the aggregation mechanism of the synthesized surfactant w a s greatly influenced by the conversion of t h e head group from -COO- to -COOH, which is similar to the natural fatty acids in aqueous form.

Cohort profile: cerebral palsy in the Norwegian and Danish birth cohorts (MOBAND-CP)

PubMed Central

Tollånes, Mette C; Strandberg-Larsen, Katrine; Forthun, Ingeborg; Petersen, Tanja Gram; Moster, Dag; Andersen, Anne-Marie Nybo; Stoltenberg, Camilla; Olsen, Jørn; Wilcox, Allen J

2016-01-01

Purpose The purpose of MOthers and BAbies in Norway and Denmark cerebral palsy (MOBAND-CP) was to study CP aetiology in a prospective design. Participants MOBAND-CP is a cohort of more than 210 000 children, created as a collaboration between the world's two largest pregnancy cohorts—the Norwegian Mother and Child Cohort study (MoBa) and the Danish National Birth Cohort. MOBAND-CP includes maternal interview/questionnaire data collected during pregnancy and follow-up, plus linked information from national health registries. Findings to date Initial harmonisation of data from the 2 cohorts has created 140 variables for children and their mothers. In the MOBAND-CP cohort, 438 children with CP have been identified through record linkage with validated national registries, providing by far the largest such sample with prospectively collected detailed pregnancy data. Several studies investigating various hypotheses regarding CP aetiology are currently on-going. Future plans Additional data can be harmonised as necessary to meet requirements of new projects. Biological specimens collected during pregnancy and at delivery are potentially available for assay, as are results from assays conducted on these specimens for other projects. The study size allows consideration of CP subtypes, which is rare in aetiological studies of CP. In addition, MOBAND-CP provides a platform within the context of a merged birth cohort of exceptional size that could, after appropriate permissions have been sought, be used for cohort and case-cohort studies of other relatively rare health conditions of infants and children. PMID:27591025

Study Protocol, Sample Characteristics, and Loss to Follow-Up: The OPPERA Prospective Cohort Study

PubMed Central

Bair, Eric; Brownstein, Naomi C.; Ohrbach, Richard; Greenspan, Joel D.; Dubner, Ron; Fillingim, Roger B.; Maixner, William; Smith, Shad; Diatchenko, Luda; Gonzalez, Yoly; Gordon, Sharon; Lim, Pei-Feng; Ribeiro-Dasilva, Margarete; Dampier, Dawn; Knott, Charles; Slade, Gary D.

2013-01-01

When studying incidence of pain conditions such as temporomandibular disorders (TMDs), repeated monitoring is needed in prospective cohort studies. However, monitoring methods usually have limitations and, over a period of years, some loss to follow-up is inevitable. The OPPERA prospective cohort study of first-onset TMD screened for symptoms using quarterly questionnaires and examined symptomatic participants to definitively ascertain TMD incidence. During the median 2.8-year observation period, 16% of the 3,263 enrollees completed no follow-up questionnaires, others provided incomplete follow-up, and examinations were not conducted for one third of symptomatic episodes. Although screening methods and examinations were found to have excellent reliability and validity, they were not perfect. Loss to follow-up varied according to some putative TMD risk factors, although multiple imputation to correct the problem suggested that bias was minimal. A second method of multiple imputation that evaluated bias associated with omitted and dubious examinations revealed a slight underestimate of incidence and some small biases in hazard ratios used to quantify effects of risk factors. Although “bottom line” statistical conclusions were not affected, multiply-imputed estimates should be considered when evaluating the large number of risk factors under investigation in the OPPERA study. Perspective These findings support the validity of the OPPERA prospective cohort study for the purpose of investigating the etiology of first-onset TMD, providing the foundation for other papers investigating risk factors hypothesized in the OPPERA project. PMID:24275220

Methodology of the Pelotas birth cohort study from 1982 to 2004-5, Southern Brazil

PubMed Central

Barros, Fernando C; Victora, Cesar G; Horta, Bernardo L; Gigante, Denise P

2009-01-01

OBJECTIVE: To describe the methods employed in the longitudinal and follow-up studies of children born in Pelotas (Southern Brazil) in 1982. METHODS: The cohort began with a perinatal health survey that included all 6,011 children born in maternity wards in Pelotas in 1982. The 5,914 children born alive in the city were included in the follow-up studies. By 2004-5, we had conducted eight follow-ups, which consisted of the administration of questionnaires to mothers and/or cohort members, depending on age, in addition to anthropometric and clinical examination. Cohort subjects are described in terms of demographic, socioeconomic, and health-related variables collected during early follow-up studies, which are used as exposure variables. RESULTS: The majority of subjects in the cohort were followed for 23 years and on multiple occasions. The most successful follow-ups were those preceded by a city census. Using this method, we were able to locate 87.2% of subjects in 1984 (mean age 19 months), 84.1% in 1986 (mean age 43 months), and 77.4% in 2004-5, and 77.4% in 2004-5 (mean age 23 years). CONCLUSIONS: Birth cohort studies can be carried out successfully in developing countries, and the methods employed in this life-cycle study have allowed us to investigate the influence of early exposures in determining disease outcomes in adult life. PMID:19142340

Genome-Wide Association of CKD Progression: The Chronic Renal Insufficiency Cohort Study.

PubMed

Parsa, Afshin; Kanetsky, Peter A; Xiao, Rui; Gupta, Jayanta; Mitra, Nandita; Limou, Sophie; Xie, Dawei; Xu, Huichun; Anderson, Amanda Hyre; Ojo, Akinlolu; Kusek, John W; Lora, Claudia M; Hamm, L Lee; He, Jiang; Sandholm, Niina; Jeff, Janina; Raj, Dominic E; Böger, Carsten A; Bottinger, Erwin; Salimi, Shabnam; Parekh, Rulan S; Adler, Sharon G; Langefeld, Carl D; Bowden, Donald W; Groop, Per-Henrik; Forsblom, Carol; Freedman, Barry I; Lipkowitz, Michael; Fox, Caroline S; Winkler, Cheryl A; Feldman, Harold I

2017-03-01

The rate of decline of renal function varies significantly among individuals with CKD. To understand better the contribution of genetics to CKD progression, we performed a genome-wide association study among participants in the Chronic Renal Insufficiency Cohort Study. Our outcome of interest was CKD progression measured as change in eGFR over time among 1331 blacks and 1476 whites with CKD. We stratified all analyses by race and subsequently, diabetes status. Single-nucleotide polymorphisms (SNPs) that surpassed a significance threshold of P <1×10 -6 for association with eGFR slope were selected as candidates for follow-up and secondarily tested for association with proteinuria and time to ESRD. We identified 12 such SNPs among black patients and six such SNPs among white patients. We were able to conduct follow-up analyses of three candidate SNPs in similar (replication) cohorts and eight candidate SNPs in phenotype-related (validation) cohorts. Among blacks without diabetes, rs653747 in LINC00923 replicated in the African American Study of Kidney Disease and Hypertension cohort (discovery P =5.42×10 -7 ; replication P =0.039; combined P =7.42×10 -9 ). This SNP also associated with ESRD (hazard ratio, 2.0 (95% confidence interval, 1.5 to 2.7); P =4.90×10 -6 ). Similarly, rs931891 in LINC00923 associated with eGFR decline ( P =1.44×10 -4 ) in white patients without diabetes. In summary, SNPs in LINC00923 , an RNA gene expressed in the kidney, significantly associated with CKD progression in individuals with nondiabetic CKD. However, the lack of equivalent cohorts hampered replication for most discovery loci. Further replication of our findings in comparable study populations is warranted. Copyright © 2017 by the American Society of Nephrology.

Microsurgery Versus Stereotactic Radiosurgery for Brain Arteriovenous Malformations: A Matched Cohort Study.

PubMed

Chen, Ching-Jen; Ding, Dale; Wang, Tony R; Buell, Thomas J; Ilyas, Adeel; Ironside, Natasha; Lee, Cheng-Chia; Kalani, M Yashar; Park, Min S; Liu, Kenneth C; Sheehan, Jason P

2018-05-12

Microsurgery (MS) and stereotactic radiosurgery (SRS) remain the preferred interventions for the curative treatment of brain arteriovenous malformations (AVM), but their relative efficacy remains incompletely defined. To compare the outcomes of MS to SRS for AVMs through a retrospective, matched cohort study. We evaluated institutional databases of AVM patients who underwent MS and SRS. MS-treated patients were matched, in a 1:1 ratio based on patient and AVM characteristics, to SRS-treated patients. Statistical analyses were performed to compare outcomes data between the 2 cohorts. The primary outcome was defined as AVM obliteration without a new permanent neurological deficit. The matched MS and SRS cohorts were each comprised of 59 patients. Both radiological (85 vs 11 mo; P < .001) and clinical (92 vs 12 mo; P < .001) follow-up were significantly longer for the SRS cohort. The primary outcome was achieved in 69% of each cohort. The MS cohort had a significantly higher obliteration rate (98% vs 72%; P = .001), but also had a significantly higher rate of new permanent deficit (31% vs 10%; P = .011). The posttreatment hemorrhage rate was significantly higher for the SRS cohort (10% for SRS vs 0% for MS; P = .027). In subgroup analyses of ruptured and unruptured AVMs, no significant differences between the primary outcomes were observed. For patients with comparable AVMs, MS and SRS afford similar rates of deficit-free obliteration. Nidal obliteration is more frequently achieved with MS, but this intervention also incurs a greater risk of new permanent neurological deficit.

Investing in Prospective Cohorts for Etiologic Study of Occupational Exposures

EPA Science Inventory

Prospective cohorts have played a major role in understanding the role of diet, physical activity, medical conditions, and genes in the development of many diseases, but have not been widely used in the study of occupational exposures. Studies in agriculture are an exception. W...

Mitochondrial genetic haplogroups and incident obesity: a longitudinal cohort study.

PubMed

Veronese, Nicola; Stubbs, Brendon; Koyanagi, Ai; Vaona, Alberto; Demurtas, Jacopo; Schofield, Patricia; Thompson, Trevor; Maggi, Stefania

2018-04-01

A small number of case-control studies have suggested that mitochondrial haplogroups could be associated with obesity. We examined whether obesity risk was influenced by mitochondrial haplogroup in a large North American cohort across an 8-year period. We conducted a longitudinal cohort study including individuals from the Osteoarthritis Initiative. Mitochondrial haplogroups were determined by sequencing and PCR-RFLP techniques using this nomenclature: HV, JT, KU, IWX, and super HV/others. The strength of the association between mitochondrial haplogroups and incident obesity was quantified with hazard ratios (HRs), adjusted for potential confounders using a Cox's regression analysis. Overall, 2342 non-obese Caucasian participants (56.7% women) with a mean ± SD age of 62.0 ± 9.5 years at baseline were included. During a median follow-up of 8 years, 334 individuals ( = 14.3% of baseline population) became obese. After adjusting for nine potential confounders, the haplogroups IWX carried a significant 48% higher risk of obesity (HR = 1.48; 95% CI: 1.02-2.39) compared to the HV haplotype (the most frequent type). Only the presence of the IWX haplogroups appears to be linked to increased obesity risk, independent of potential baseline confounders. Future cohort studies are needed to confirm these findings and to determine potential underlying mechanisms.

The Shozu Herpes Zoster (SHEZ) study: rationale, design, and description of a prospective cohort study.

PubMed

Takao, Yukiko; Miyazaki, Yoshiyuki; Onishi, Fumitake; Kumihashi, Hideaki; Gomi, Yasuyuki; Ishikawa, Toyokazu; Okuno, Yoshinobu; Mori, Yasuko; Asada, Hideo; Yamanishi, Koichi; Iso, Hiroyasu

2012-01-01

The incidence and risk factors for herpes zoster have been studied in cross-sectional and cohort studies, although most such studies have been conducted in Western countries. Evidence from Asian populations is limited, and no cohort study has been conducted in Asia. We are conducting a 3-year prospective cohort study in Shozu County in Kagawa Prefecture, Japan to determine the incidence and predictive and immunologic factors for herpes zoster among Japanese. The participants are followed for 3 years, and a telephone survey is conducted every 4 weeks. The participants were assigned to 1 of 3 studies. Participants in study A gave information on past history of herpes zoster and completed health questionnaires. Study B participants additionally underwent varicella-zoster virus (VZV) skin testing, and study C participants additionally underwent blood testing. If the participants develop herpes zoster, we evaluate clinical symptoms, measure cell-mediated immunity and humoral immunity using venous blood sampling, photograph skin areas with rash, conduct virus identification testing by polymerase chain reaction (PCR) and virus isolation from crust sampling, and evaluate postherpetic pain. We recruited 12 522 participants aged 50 years or older in Shozu County from December 2009 through November 2010. The participation rate was 65.7% of the target population. The present study is likely to provide valuable data on the incidence and predictive and immunologic factors for herpes zoster in a defined community-based population of Japanese.

The Shozu Herpes Zoster (SHEZ) Study: Rationale, Design, and Description of a Prospective Cohort Study

PubMed Central

Takao, Yukiko; Miyazaki, Yoshiyuki; Onishi, Fumitake; Kumihashi, Hideaki; Gomi, Yasuyuki; Ishikawa, Toyokazu; Okuno, Yoshinobu; Mori, Yasuko; Asada, Hideo; Yamanishi, Koichi; Iso, Hiroyasu

2012-01-01

Background The incidence and risk factors for herpes zoster have been studied in cross-sectional and cohort studies, although most such studies have been conducted in Western countries. Evidence from Asian populations is limited, and no cohort study has been conducted in Asia. We are conducting a 3-year prospective cohort study in Shozu County in Kagawa Prefecture, Japan to determine the incidence and predictive and immunologic factors for herpes zoster among Japanese. Methods The participants are followed for 3 years, and a telephone survey is conducted every 4 weeks. The participants were assigned to 1 of 3 studies. Participants in study A gave information on past history of herpes zoster and completed health questionnaires. Study B participants additionally underwent varicella-zoster virus (VZV) skin testing, and study C participants additionally underwent blood testing. If the participants develop herpes zoster, we evaluate clinical symptoms, measure cell-mediated immunity and humoral immunity using venous blood sampling, photograph skin areas with rash, conduct virus identification testing by polymerase chain reaction (PCR) and virus isolation from crust sampling, and evaluate postherpetic pain. Results We recruited 12 522 participants aged 50 years or older in Shozu County from December 2009 through November 2010. The participation rate was 65.7% of the target population. Conclusions The present study is likely to provide valuable data on the incidence and predictive and immunologic factors for herpes zoster in a defined community-based population of Japanese. PMID:22343323

Chinese-French Case Study of English Language Learning via Wikispaces, Animoto and Skype

ERIC Educational Resources Information Center

Hartwell, Laura M.; Zou, Bin

2013-01-01

This paper reports on the learning experience of Chinese and French students participating in a computer mediated communication (CMC) collaboration conducted in English and supported by Wikispaces, Animoto, and Skype. Several studies have investigated CMC contexts in which at least some participants were native speakers. Here, we address the…

Environmental/Thermal Barrier Coatings for Ceramic Matrix Composites: Thermal Tradeoff Studies

NASA Technical Reports Server (NTRS)

Murthy, Pappu L. M.; Brewer, David; Shah, Ashwin R.

2007-01-01

Recent interest in environmental/thermal barrier coatings (EBC/TBCs) has prompted research to develop life-prediction methodologies for the coating systems of advanced high-temperature ceramic matrix composites (CMCs). Heat-transfer analysis of EBC/TBCs for CMCs is an essential part of the effort. It helps establish the resulting thermal profile through the thickness of the CMC that is protected by the EBC/TBC system. This report documents the results of a one-dimensional analysis of an advanced high-temperature CMC system protected with an EBC/TBC system. The one-dimensional analysis was used for tradeoff studies involving parametric variation of the conductivity; the thickness of the EBC/TBCs, bond coat, and CMC substrate; and the cooling requirements. The insight gained from the results will be used to configure a viable EBC/TBC system for CMC liners that meet the desired hot surface, cold surface, and substrate temperature requirements.

Specialist Cohort Event Monitoring studies: a new study method for risk management in pharmacovigilance.

PubMed

Layton, Deborah; Shakir, Saad A W

2015-02-01

The evolving regulatory landscape has heightened the need for innovative, proactive, efficient and more meaningful solutions for 'real-world' post-authorization safety studies (PASS) that not only align with risk management objectives to gather additional safety monitoring information or assess a pattern of drug utilization, but also satisfy key regulatory requirements for marketing authorization holder risk management planning and execution needs. There is a need for data capture across the primary care and secondary care interface, or for exploring use of new medicines in secondary care to support conducting PASS. To fulfil this need, event monitoring has evolved. The Specialist Cohort Event Monitoring (SCEM) study is a new application that enables a cohort of patients prescribed a medicine in the hospital and secondary care settings to be monitored. The method also permits the inclusion of a comparator cohort of patients receiving standard care, or another counterfactual comparator group, to be monitored concurrently, depending on the study question. The approach has been developed in parallel with the new legislative requirement for pharmaceutical companies to undertake a risk management plan as part of post-authorization safety monitoring. SCEM studies recognize that the study population comprises those patients who may have treatment initiated under the care of specialist health care professionals and who are more complex in terms of underlying disease, co-morbidities and concomitant medications than the general disease population treated in primary care. The aims of this paper are to discuss the SCEM new-user study design, rationale and features that aim to address possible bias (such as selection bias) and current applications.

The Environment and Reproductive Health (EARTH) Study: A Prospective Preconception Cohort.

PubMed

Messerlian, Carmen; Williams, Paige L; Ford, Jennifer B; Chavarro, Jorge E; Mínguez-Alarcón, Lidia; Dadd, Ramace; Braun, Joseph M; Gaskins, Audrey J; Meeker, John D; James-Todd, Tamarra; Chiu, Yu-Han; Nassan, Feiby L; Souter, Irene; Petrozza, John; Keller, Myra; Toth, Thomas L; Calafat, Antonia M; Hauser, Russ

2018-02-01

The Environment and Reproductive Health (EARTH) Study is an ongoing prospective preconception cohort designed to investigate the impact of environmental, nutritional, and lifestyle factors among both women and men on fertility and pregnancy outcomes. The EARTH Study recruits women 18 to 45 years and men 18 to 55 years seeking fertility evaluation and treatment at the Massachusetts General Hospital (MGH) Fertility Center, Boston, USA. Women and men are eligible to join either independently or as a couple. Participants are followed from study entry throughout each fertility treatment cycle, once per trimester of pregnancy (for those achieving pregnancy), and up to labor and delivery, or until they discontinue treatment or withdraw from the study. The study collects biological samples, self-reported questionnaire data (including a food frequency questionnaire) and clinically abstracted information. As of June 2017, the study cohort included 799 women and 487 men (447 couples; 40 men joined without female partners). Women were on average 34.7 years old at time of enrolment and predominantly Caucasian (81%), educated (49% have a graduate degree), and nulliparous (83%). Men were on average 36.6 years at baseline and mostly Caucasian (86%) and never-smokers (67%). The EARTH Study is one of the few cohorts designed to examine multiple potentially critical windows of vulnerability, including the paternal and maternal preconception windows and the periconception and prenatal windows in pregnancy. It is also one of the few human studies that has assessed potential interactions between environmental exposures and dietary factors.

Risk of thyroid cancer in patients with thyroiditis: a population-based cohort study.

PubMed

Liu, Chien-Liang; Cheng, Shih-Ping; Lin, Hui-Wen; Lai, Yuen-Liang

2014-03-01

The causative relationship between autoimmune thyroiditis and thyroid cancer remains a controversial issue. The aim of this population-based study was to investigate the risk of thyroid cancer in patients with thyroiditis. From the Longitudinal Health Insurance Database 2005 (LHID2005) of Taiwan, we identified adult patients newly diagnosed with thyroiditis between 2004 and 2009 (n = 1,654). The comparison cohort (n = 8,270) included five randomly selected age- and sex-matched controls for each patient in the study cohort. All patients were followed up from the date of cohort entry until they developed thyroid cancer or to the end of 2010. Multivariate Cox regression was used to assess the risk of developing thyroid cancer. A total of 1,000 bootstrap replicates were created for internal validation. A total of 35 patients developed thyroid cancer during the study period, of whom 24 were from the thyroiditis cohort and 11 were from the comparison cohort (incidence 353 and 22 per 100,000 person-years, respectively). After adjusting for potential confounding factors, the hazard ratio (HR) for thyroid cancer in patients with thyroiditis was 13.24 (95 % CI 6.40-27.39). Excluding cancers occurring within 1 year of follow-up, the HR remained significantly increased (6.64; 95 % CI 2.35-18.75). Hypothyroidism was not an independent factor associated with the occurrence of thyroid cancer. We found an increased risk for the development of thyroid cancer after a diagnosis of thyroiditis, independent of comorbidities.

Studies on improvement of pharmaceutical preparations prescribed in hospitals. IV. Dibekacin sulfate viscous solution for treatment of mouth and throat wounds.

PubMed

Namiki, N; Yokoyama, H; Moriya, K; Fukuda, M; Takashima, T; Uchida, Y; Yuasa, H; Kanaya, Y

1986-11-01

For the purpose of preventing suppuration of wounds of the oral cavity and throat, we attempted to develop a viscous solution of dibekacin sulfate (DKB) as a suitable medication. Solutions of different viscosity and antibacterial potency were prepared by mixing DKB, sodium carboxymethyl cellulose (CMC-Na), and water in varying proportions. Studies were then performed to ascertain relationships between the concentration of CMC-Na pH and viscosity, and between the viscosity and diffusion of DKB. The concentration of CMC-Na giving rise to optimal clinical efficacy was determined, and the concentration of DKB necessary for clinical treatment was estimated on the basis of the ionic binding constant between DKB and CMC-Na. As a result, the optimum CMC-Na concentration was found to be 2%, while the optimum DKB concentration was estimated to be 100 micrograms/ml.

Mediterranean diet and telomere length in Nurses' Health Study: population based cohort study.

PubMed

Crous-Bou, Marta; Fung, Teresa T; Prescott, Jennifer; Julin, Bettina; Du, Mengmeng; Sun, Qi; Rexrode, Kathryn M; Hu, Frank B; De Vivo, Immaculata

2014-12-02

To examine whether adherence to the Mediterranean diet was associated with longer telomere length, a biomarker of aging. Population based cohort study. Nurses' Health Study, an ongoing prospective cohort study of 121,700 nurses enrolled in 1976; in 1989-90 a subset of 32,825 women provided blood samples. 4676 disease-free women from nested case-control studies within the Nurses' Health Study with telomere length measured who also completed food frequency questionnaires. Association between relative telomere lengths in peripheral blood leukocytes measured by quantitative real time polymerase chain reaction and Alternate Mediterranean Diet score calculated from self reported dietary data. Greater adherence to the Mediterranean diet was associated with longer telomeres after adjustment for potential confounders. Least squares mean telomere length z scores were -0.038 (SE 0.035) for the lowest Mediterranean diet score groups and 0.072 (0.030) for the highest group (P for trend = 0.004). In this large study, greater adherence to the Mediterranean diet was associated with longer telomeres. These results further support the benefits of adherence to the Mediterranean diet for promoting health and longevity. © Crous-Bou et al 2014.

[Validity of self-reported metabolic syndrome components in a cohort study].

PubMed

Fernández-Montero, Alejandro; Beunza, Juan J; Bes-Rastrollo, Maira; Barrio, María T; de la Fuente-Arrillaga, Carmen; Moreno-Galarraga, Laura; Martínez-González, Miguel A

2011-01-01

To assess the accuracy of self-reported data needed to constitute the metabolic syndrome in the University of Navarra Follow-Up [Seguimiento Universidad de Navarra (SUN)] cohort. The SUN project is a multi-purpose prospective cohort, formed by more than 20,000 university graduates, followed-up using surface mail questionnaires every 2 years. In a sample of 287 cohort participants, self-reported data on the criteria needed to define the metabolic syndrome (waist circumference, blood pressure, triglycerides, high-density lipoprotein-cholesterol and glucose) were compared with the same biometric data obtained by blood tests or measured by trained medical staff. Intra-class correlation coefficients with 95% confidence intervals (95% CI), relative mean error and agreement limits according to the method proposed by Bland and Altman were calculated for each variable studied. High intraclass correlations were found for the values of waist circumference (r=0.86, 95% CI: 0.80-0.90) and triglycerides (r=0.71, 95%CI: 0.61-0.79). Moderate intraclass correlations were found (between 0.46 and 0.63) for the other factors. Relative mean errors were always<2.5%, and >91% of values were within the limits of agreement for all variables. The results suggest that self-declared data on the criteria of metabolic syndrome obtained in the SUN cohort, though with some caution, are sufficiently accurate to be used in epidemiological studies. Copyright © 2010 SESPAS. Published by Elsevier Espana. All rights reserved.

Mushroom Consumption and Incident Dementia in Elderly Japanese: The Ohsaki Cohort 2006 Study.

PubMed

Zhang, Shu; Tomata, Yasutake; Sugiyama, Kemmyo; Sugawara, Yumi; Tsuji, Ichiro

2017-07-01

Both in vivo and in vitro studies have indicated that edible mushrooms may have preventive effects against cognitive impairment. However, few cohort studies have yet examined the relationship between mushroom consumption and incident dementia. We examined the relationship between mushroom consumption and incident dementia in a population of elderly Japanese subjects. Prospective cohort study. Ohsaki Cohort 2006 Study. 13,230 individuals aged ≥65 years living in Ohsaki City, northeastern Japan. Daily mushroom consumption, other lifestyle factors, and dementia incidence. The 5.7 years incidence of dementia was 8.7%. In comparison with participants who consumed mushrooms <1 time/wk, the multi-adjusted HRs (95% CI) for incident dementia among those did so 1-2 times/week and ≥3 times/week were 0.95 (0.81, 1.10) and 0.81 (0.69, 0.95), respectively (P-trend <.01). The inverse association persisted after excluding participants whose dementia event occurred in the first 2 years of follow-up and whose baseline cognitive function was lower. The inverse association did not differ statistically in terms of vegetable consumption (P-interaction = .10). This cohort study suggests that frequent mushroom consumption is significantly associated with a lower risk of incident dementia, even after adjustment for possible confounding factors. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

Genetic causes of intellectual disability in a birth cohort: a population-based study.

PubMed

Karam, Simone M; Riegel, Mariluce; Segal, Sandra L; Félix, Têmis M; Barros, Aluísio J D; Santos, Iná S; Matijasevich, Alicia; Giugliani, Roberto; Black, Maureen

2015-06-01

Intellectual disability affects approximately 1-3% of the population and can be caused by genetic and environmental factors. Although many studies have investigated the etiology of intellectual disability in different populations, few studies have been performed in middle-income countries. The present study estimated the prevalence of genetic causes related to intellectual disability in a cohort of children from a city in south Brazil who were followed from birth. Children who showed poor performance in development and intelligence tests at the ages of 2 and 4 were included. Out of 4,231 liveborns enrolled in the cohort, 214 children fulfilled the inclusion criteria. A diagnosis was established in approximately 90% of the children evaluated. Genetic causes were determined in 31 of the children and 19 cases remained unexplained even after extensive investigation. The overall prevalence of intellectual disability in this cohort due to genetic causes was 0.82%. Because this study was nested in a cohort, there were a large number of variables related to early childhood and the likelihood of information bias was minimized by collecting information with a short recall time. This study was not influenced by selection bias, allowing identification of intellectual disability and estimation of the prevalence of genetic causes in this population, thereby increasing the possibility of providing appropriate management and/or genetic counseling. © 2015 Wiley Periodicals, Inc.

Dinitrotoluene exposure in the copper mining industry and renal cancer: a case-cohort study.

PubMed

Seidler, Andreas; Harth, Volker; Taeger, Dirk; Möhner, Matthias; Gawrych, Katarzyna; Bergmann, Annekatrin; Haerting, Johannes; Kahmann, Hans-Joachim; Bolt, Hermann Maximilian; Straif, Kurt; Brüning, Thomas

2014-04-01

To evaluate the association between dinitrotoluene (DNT) exposure and renal cancer in a case-cohort study. This case-cohort study was conducted among men born between 1920 and 1974 (n=16 441) who were gainfully employed between 1953 and 1990 in one of two copper mines in Mansfeld, Saxony-Anhalt, former German Democratic Republic, and followed up till 31 December 2006. The study included 109 cases with renal cancer identified by record linkage with the Common Cancer Registry of the New Federal States of Germany (GKR) or by a network of pathology institutes. A comparison subcohort of 999 cohort members was selected at random from the total cohort. Duration and intensity of inhalation and dermal exposure to DNT were assessed on the basis of a job exposure matrix. A time-dependent Cox proportional hazards model modified for case-cohort design was used to assess the relationship between cumulative inhalation and dermal DNT exposure and renal cancer. Elevated risks were found for medium (HR=2.73; 95% CI 1.00 to 7.42) and high (HR=1.81; 95% CI 0.75 to 4.33) dermal exposure to DNT. Relative risks for medium inhalation exposure to DNT were not increased (HR=0.93; 95% CI 0.48 to 1.79) while relative risks for high inhalation exposure to DNT were elevated to 1.36 (95% CI 0.84 to 2.21). We found a statistically significant HR of 2.12 (95% CI 1.03 to 4.37) for combined medium or high inhalation and medium or high dermal exposure to DNT. According to our case-cohort study, dermal and inhalation exposure to DNT is associated with increased renal cancer risk.

The Mother-Infant Study Cohort (MISC): Methodology, challenges, and baseline characteristics

PubMed Central

Hashim, Mona; Shaker Obaid, Reyad; Hasan, Hayder; Naja, Farah; Al Ghazal, Hessa; Jan Jan Mohamed, Hamid; Al Hilali, Marwa; Rayess, Rana; Izzaldin, Ghamra

2018-01-01

Background The United Arab Emirates (UAE) exhibits alarming high prevalence of Non-Communicable Diseases (NCDs) and their risk factors. Emerging evidence highlighted the role of maternal and early child nutrition in preventing later-onset NCDs. The objectives of this article are to describe the design and methodology of the first Mother and Infant Study Cohort (MISC) in UAE; present the baseline demographic characteristics of the study participants; and discuss the challenges of the cohort and their respective responding strategies. Methods The MISC is an ongoing two-year prospective cohort study which recruited Arab pregnant women in their third trimester from prenatal clinics in Dubai, Sharjah and Ajman. Participants will be interviewed six times (once during pregnancy, at delivery, and at 2, 6, 12 and 24months postpartum). Perinatal information is obtained from hospital records. Collected data include socio-demographic characteristics, lifestyle, dietary intake and anthropometry; infant feeding practices, cognitive development; along with maternal and infant blood profile and breast milk profile. Results The preliminary results reported that 256 completed baseline assessment (mean age: 30.5±6.0 years; 76.6% multiparous; about 60% were either overweight or obese before pregnancy). The prevalence of gestational diabetes was 19.2%. Upon delivery, 208 women-infant pairs were retained (mean gestational age: 38.5±1.5 weeks; 33.3% caesarean section delivery; 5.3% low birthweight; 5.7% macrosomic deliveries). Besides participant retention, the main encountered challenges pertained to cultural complexity, underestimation the necessary start-up time, staff, and costs, and biochemical data collection. Conclusions Despite numerous methodological, logistical and sociocultural challenges, satisfactory follow-up rates are recorded. Strategies addressing challenges are documented, providing information for planning and implementing future birth cohort studies locally and

Birth cohorts in Asia: The importance, advantages, and disadvantages of different-sized cohorts.

PubMed

Kishi, Reiko; Araki, Atsuko; Minatoya, Machiko; Itoh, Sachiko; Goudarzi, Houman; Miyashita, Chihiro

2018-02-15

Asia contains half of the world's children, and the countries of Asia are the most rapidly industrializing nations on the globe. Environmental threats to the health of children in Asia are myriad. Several birth cohorts were started in Asia in early 2000, and currently more than 30 cohorts in 13 countries have been established for study. Cohorts can contain from approximately 100-200 to 20,000-30,000 participants. Furthermore, national cohorts targeting over 100,000 participants have been launched in Japan and Korea. The aim of this manuscript is to discuss the importance of Asian cohorts, and the advantages and disadvantages of different-sized cohorts. As for case, one small-sized (n=514) cohort indicate that even relatively low level exposure to dioxin in utero could alter birth size, neurodevelopment, and immune and hormonal functions. Several Asian cohorts focus prenatal exposure to perfluoroalkyo substances and reported associations with birth size, thyroid hormone levels, allergies and neurodevelopment. Inconsistent findings may possibly be explained by the differences in exposure levels and target chemicals, and by possible statistical errors. In a smaller cohort, novel hypotheses or preliminary examinations are more easily verifiable. In larger cohorts, the etiology of rare diseases, such as birth defects, can be analyzed; however, they require a large cost and significant human resources. Therefore, conducting studies in only one large cohort may not always be the best strategy. International collaborations, such as the Birth Cohort Consortium of Asia, would cover the inherent limitation of sample size in addition to heterogeneity of exposure, ethnicity, and socioeconomic conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Hyperthyroidism and female urinary incontinence: a population-based cohort study.

PubMed

Chung, Shiu-Dong; Chen, Yi-Kuang; Chen, Yi-Hua; Lin, Herng-Ching

2011-11-01

The imbalanced autonomic nervous system present in hyperthyroidism may cause lower urinary tract symptoms. Urinary incontinence (UI) is the most bothersome lower urinary tract symptom; however, in the literature, reports regarding urinary dysfunction and/or incontinence among hyperthyroid patients are scarce. This population-based cohort study aimed to examine the relationship between hyperthyroidism in women and the risk of developing UI in Taiwan. This study used data from the Longitudinal Health Insurance Database. For this study, 10,817 female patients diagnosed with hyperthyroidism from 2001 to 2005 were recruited together with a comparison cohort of 54,085 matched enrollees who did not have a history of hyperthyroidism. All patients were tracked for a 3-year period from their index date to identify those who had a subsequent UI. The stratified Cox proportional hazards models were used to compute the risk of UI between study and comparison cohorts. During the follow-up period, of 64,169 patients, 173 (1·60%) from the hyperthyroidism group and 560 (1·04%) from the comparison group, had a diagnosis of UI. The regression analysis showed that, after adjusting for monthly income, geographic region, urbanization level of the community in which the patient resided, obesity and hysterectomy, patients with hyperthyroidism were more likely to have UI during the 3-year follow-up period than the comparison patients (hazard ratio = 1·54; 95% CI = 1·30-1·83; P < 0·001). Our results suggest an increased risk of UI in patients with hyperthyroidism at the 3-year follow-up. © 2011 Blackwell Publishing Ltd.

Association between diverticular disease and Ehlers-Danlos syndrome: a 13-year nationwide population-based cohort study.

PubMed

Leganger, Julie; Søborg, Marie-Louise Kulas; Mortensen, Laura Quitzau; Gregersen, Rasmus; Rosenberg, Jacob; Burcharth, Jakob

2016-12-01

The aim of this study was to examine occurrence and consequences of diverticular disease in patients with Ehlers-Danlos syndrome (EDS) compared with a matched cohort. This nationwide population-based cohort study was conducted using data from medical registers in Denmark from year 2000 to 2012. The EDS cohort was identified using the specific diagnosis code for EDS and was randomly matched in a ratio of 1:20 by sex and date of birth (±1 year) with persons from the Danish general population. The occurrence of diverticular disease and the clinical characteristics of the initial diverticular event were compared between the EDS cohort and the comparison cohort. The first admission with diverticulitis was identified, and severity of diverticulitis, treatment, colonoscopies, length of stay, and 30-day mortality were investigated. We identified 1336 patients with EDS and matched a control cohort of 26,720 patients. The occurrence of diverticular disease in the EDS cohort (2.0 %) and the comparison cohort (0.68 %) differed significantly (p < 0.001). At the first diverticular event, the majority of patients were women (85 % for EDS and 87 % for the comparison cohort). Mean age, localization, and type of contact did not differ significantly. Admission with diverticulitis (1.0 % for EDS and 0.34 % for the comparison cohort) differed significantly (p < 0.001). We found no significant difference in severity of diverticulitis, treatment, length of stay, or 30-day mortality between the EDS and the comparison cohorts. Patients with EDS had an increased occurrence of overall diverticular events and admissions with diverticulitis compared with the general population.

Design and conduct of an internet-based preconception cohort study in North America: Pregnancy Study Online (PRESTO)

PubMed Central

Wise, Lauren A; Rothman, Kenneth J.; Mikkelsen, Ellen M.; Stanford, Joseph B.; Wesselink, Amelia K.; McKinnon, Craig; Gruschow, Siobhan M.; Horgan, Casie E.; Wiley, Aleta S.; Hahn, Kristen A.; Sørensen, Henrik Toft; Hatch, Elizabeth E.

2015-01-01

Background We launched the Boston University Pregnancy Study Online (PRESTO) to assess the feasibility of carrying out an internet-based preconception cohort study in the U.S. and Canada. Methods We recruited female participants age 21–45 and their male partners through internet advertisements, word of mouth, and flyers. Female participants were randomized with 50% probability to receive a subscription to FertilityFriend.com (FF), a web-based program that collects real-time data on menstrual characteristics. We compared recruitment methods within PRESTO, assessed the cost-efficiency of PRESTO relative to its Danish counterpart (Snart-Gravid), and validated retrospectively-reported date of last menstrual period (LMP) against FF data. Results After 99 weeks of recruitment (2013–2015), 2,421 women enrolled; 1,384 (57%) invited their male partners to participate, of whom 693 (50%) enrolled. Baseline characteristics were balanced across randomization groups. Cohort retention was similar among those randomized vs. not randomized to FF (84% vs. 81%). At study enrollment, 56%, 22%, and 22% couples had been trying to conceive for <3, 3–5, and ≥6 months, respectively. The cost per subject enrolled was $146 (2013 $US), which was similar to our companion Danish study and half that of a traditional cohort study. Among FF users who conceived, >97% reported their LMP on the PRESTO questionnaire within 1 day of the LMP recorded via FF. Conclusions Use of the internet as a method of recruitment and follow-up in a North American preconception cohort study was feasible and cost-effective. PMID:26111445

Cohort-Sequential Study of Conflict Inhibition during Middle Childhood

ERIC Educational Resources Information Center

Rollins, Leslie; Riggins, Tracy

2017-01-01

This longitudinal study examined developmental changes in conflict inhibition and error correction in three cohorts of children (5, 7, and 9 years of age). At each point of assessment, children completed three levels of Luria's tapping task (1980), which requires the inhibition of a dominant response and maintenance of task rules in working…

The Taiwan Birth Panel Study: a prospective cohort study for environmentally- related child health

PubMed Central

2011-01-01

Background The Taiwan Birth Panel Study (TBPS) is a prospective follow-up study to investigate the development of child health and disease in relation to in-utero and/or early childhood environmental exposures. The rationale behind the establishment of such a cohort includes the magnitude of potential environmental exposures, the timing of exposure window, fatal and children's susceptibility to toxicants, early exposure delayed effects, and low-level or unknown neurodevelopmental toxicants. Methods A total of 486 mother-infant paired was enrolled from April 2004 to January 2005 in this study. Maternal blood before delivery, placenta and umbilical cord blood at birth, and mothers' urine after delivery were collected. The follow-up was scheduled at birth, 4, 6 months, and 1, 2, 3 and 5 years. The children's blood, urine, hair, and saliva were collected at 2 years of age and children's urine was collected at 5 years of age as well. The study has been approved by the ethical committee of National Taiwan University Hospital. All the subjects signed the inform consent on entering the study and each of the follow up. Results Through this prospective birth cohort, the main health outcomes were focused on child growth, neurodevelopment, behaviour problem and atopic diseases. We investigated the main prenatal and postnatal factors including smoking, heavy metals, perfluorinated chemicals, and non-persistent pesticides under the consideration of interaction of the environment and genes. Conclusions This cohort study bridges knowledge gaps and answers unsolved issues in the low-level, prenatal or postnatal, and multiple exposures, genetic effect modification, and the initiation and progression of "environmentally-related childhood diseases." PMID:21838884

Active cigarette smoking and the risk of breast cancer: a cohort study.

PubMed

Catsburg, Chelsea; Kirsh, Victoria A; Soskolne, Colin L; Kreiger, Nancy; Rohan, Thomas E

2014-08-01

Tobacco use has been implicated in the etiology of a large number of cancers, and there exists substantial biological plausibility that it could also be involved in breast carcinogenesis. Despite this, epidemiological evidence to date is inconsistent. The aim of this study was to investigate the role of active smoking and the risk of incident, invasive breast cancer using a prospective cohort of women from the Canadian Study of Diet, Lifestyle and Health. Using a case-cohort design, an age-stratified subcohort of 3314 women was created from 39,532 female participants who returned completed self-administered lifestyle and dietary questionnaires at baseline. A total of 1096 breast cancer cases were identified in the entire cohort (including 141 cases from the subcohort) by linkage to the Canadian Cancer Registry. Cox regression models were used to estimate hazard ratios for the association between the different smoking exposures and the risk of breast cancer, using a modification for the case-cohort design. After carefully considering early-life exposures and potential confounders, we found no association between any smoking exposure and risk of breast cancer in this study (Hazard ratio=1.00, 95% confidence interval=0.87-1.17 for ever vs never smokers). Although these results cannot rule out an association between smoking and breast cancer, they do agree with the current literature suggesting that, if an association does exist, it is relatively weak. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Study of Psychological Distress in Two Cohorts of First-Year Medical Students that Underwent Different Admission Selection Processes

PubMed Central

Yusoff, Muhamad Saiful Bahri; Rahim, Ahmad Fuad Abdul; Baba, Abdul Aziz; Ismail, Shaiful Bahari; Esa, Ab Rahman

2012-01-01

Background: Medical training is often regarded as a stressful period. Studies have previously found that 21.6%–50% of medical students experience significant psychological distress. The present study compared the prevalence and levels of psychological distress between 2 cohorts of first-year medical students that underwent different admission selection processes. Methods: A comparative cross-sectional study was conducted by comparing 2 cohorts of first-year medical students; 1 group (cohort 1) was selected based purely on academic merit (2008/2009 cohort) and the other group (cohort 2) was selected based on academic merit, psychometric assessment, and interview performance (2009/2010 cohort). Their distress levels were measured by the General Health Questionnaire, and scores higher than 3 were considered indicative of significant psychological distress. Results: The prevalence (P = 0.003) and levels (P = 0.001) of psychological distress were significantly different between the 2 cohorts. Cohort 1 had 1.2–3.3 times higher risk of developing psychological distress compared to cohort 2 (P = 0.007). Conclusion: Cohort 2 had better psychological health than cohort 1 and was less likely to develop psychological distress. This study provided evidence of a potential benefit of multimodal student selection based on academic merit, psychometric assessment, and interview performance. This selection process might identify medical students who will maintain better psychological health. PMID:23610547

Flexural Fatigue Behavior of an EBC CMC Composite System In Air and Steam at High Temperature

NASA Technical Reports Server (NTRS)

Jaskowiak, Martha; Bur, Michael; Harder, Bryan; Gorican, Daniel

2017-01-01

Both coated and uncoated SiCSiC ceramic matrix composite (CMC) samples were tested in flexure under sustained peak low cycle fatigue (SPLCF) conditions in air or steam at elevated temperatures. The SiCSiC composites were reinforced with 2-D plies of boron nitride coated Hi-Nicalon Type-S SiC fibers which were woven as 5 harness satin (5HS) cloth. The composites were densified by chemical vapor infiltration (CVI) followed by slurry melt infiltration (SMI). A multilayer barium strontium aluminosilicate (BSAS) coating was applied to the samples by a plasma spray method. Fatigue loading limits were determined from monotonic flexure tests at room temperature and 1200oC. Stress levels under the proportional limit of the composite material were selected for the SPLCF tests. After cyclic testing, the composites were evaluated to determine crack propagation and failure modes in the coated and uncoated composites. Microstructural examination was used to identify coating degradation and failure modes of the EBCCMC system.

A Cohort Study of Vitamin D Intake and Melanoma Risk

PubMed Central

Asgari, Maryam M.; Maruti, Sonia S.; Kushi, Lawrence H.; White, Emily

2009-01-01

Data suggest that vitamin D intake may have chemopreventive efficacy against melanoma, but there have been no published epidemiologic studies examining the association between vitamin D intake and melanoma risk in a large prospective cohort. We examined whether dietary and supplemental vitamin D intake was associated with melanoma risk among 68,611 men and women who were participants of the Vitamins and Lifestyle cohort study. Participants reported dietary vitamin D intake over the past year and 10-year use of multivitamin and individual vitamin D supplements on a baseline questionnaire. After follow-up through 2006, 455 incident melanomas were identified through linkage to the Surveillance, Epidemiology, and End Results cancer registry. Cox proportional hazards regression models were used to estimate relative risks (RRs) and 95% confidence intervals (CIs) for vitamin D intake after adjustment for melanoma risk factors. Compared with the lowest quartile, we did not detect a risk reduction of melanoma in the highest quartiles of dietary vitamin D intake (RR = 1.31, CI = 0.94–1.82), 10-year average supplemental vitamin D intake (RR = 1.13, CI = 0.89–1.43), or combined dietary and supplemental intake (1.05, CI = 0.79–1.40). In this large prospective cohort, we did not find an association between vitamin D intake and melanoma risk. PMID:19194478

Is Child Abuse Associated with Adolescent Obesity? A Population Cohort Study.

PubMed

Hawton, Katherine; Norris, Tom; Crawley, Esther; Shield, Julian P H

Child abuse is associated with obesity in adulthood through multiple mechanisms. However, little is known about the relationship between abuse and obesity during adolescence. The aim of this study was to investigate, using a birth cohort, whether there is an association between child abuse and overweight or obesity in adolescence. This study utilizes data from the Avon Longitudinal Study of Parents and Children, a prospective cohort study based in South West England. Using data from the 4205 children with complete data at 13 and 16 years, we analyzed body mass index (BMI) and anonymous parental report of abuse. Abuse was categorized as emotional, physical, or sexual. A sub-sample of 3429 had BMI recorded at 18 years, enabling a longitudinal analysis of BMI trajectories. Using linear and logistic regression analysis, adjusting for sex and family adversity, no association was found between child abuse and BMI, BMI Z-scores, overweight, or obesity, at 13 or 16 years, with all confidence intervals straddling the null. There was weak evidence of a negative association between physical and emotional abuse and BMI trajectories between 13 and 18 years. No relationship was found between child abuse and adolescent obesity in this cohort. This challenges the assumption that adolescent obesity is linked to previous child abuse, as demonstrated for obesity in adult life. A further longitudinal study utilizing both parental and child reports with data record linkage, to improve reporting of abuse, and including neglect as an abuse category, would be desirable.

Night work and breast cancer in women: a Swedish cohort study

PubMed Central

Åkerstedt, Torbjörn; Knutsson, Anders; Narusyte, Jurgita; Svedberg, Pia; Kecklund, Göran; Alexanderson, Kristina

2015-01-01

Objectives Recent research has suggested a moderate link between night work and breast cancer in women, mainly through case–control studies, but non-significant studies are also common and cohort studies are few. The purpose of the present study was to provide new information from cohort data through investigating the association between the number of years with night work and breast cancer among women. Design Cohort study of individuals exposed to night shift work in relation to incidence of breast cancer in women. Setting Individuals in the Swedish Twin registry, with follow-up in the Swedish Cancer Registry. Participants 13 656 women from the Swedish Twin Registry, with 3404 exposed to night work. Outcome measures Breast cancer from the Swedish Cancer Registry (463 cases) during a follow-up time of 12 years. Results A Cox proportional hazards regression analysis with control for a large number of confounders showed that the HR was HR=1.68 (95% CI 0.98 to 2.88) for the group with >20 years of night work. When the follow-up time was limited to ages below 60 years, those exposed >20 years showed a HR=1.77 (95% CI 1.03 to 3.04). Shorter exposure to night work showed no significant effects. Conclusions The present results, together with previous work, suggest that night work is associated with an increased risk of breast cancer in women, but only after relatively long-term exposure. PMID:25877283

Variance Function Regression in Hierarchical Age-Period-Cohort Models: Applications to the Study of Self-Reported Health

PubMed Central

Zheng, Hui; Yang, Yang; Land, Kenneth C.

2012-01-01

Two long-standing research problems of interest to sociologists are sources of variations in social inequalities and differential contributions of the temporal dimensions of age, time period, and cohort to variations in social phenomena. Recently, scholars have introduced a model called Variance Function Regression for the study of the former problem, and a model called Hierarchical Age-Period-Cohort regression has been developed for the study of the latter. This article presents an integration of these two models as a means to study the evolution of social inequalities along distinct temporal dimensions. We apply the integrated model to survey data on subjective health status. We find substantial age, period, and cohort effects, as well as gender differences, not only for the conditional mean of self-rated health (i.e., between-group disparities), but also for the variance in this mean (i.e., within-group disparities)—and it is detection of age, period, and cohort variations in the latter disparities that application of the integrated model permits. Net of effects of age and individual-level covariates, in recent decades, cohort differences in conditional means of self-rated health have been less important than period differences that cut across all cohorts. By contrast, cohort differences of variances in these conditional means have dominated period differences. In particular, post-baby boom birth cohorts show significant and increasing levels of within-group disparities. These findings illustrate how the integrated model provides a powerful framework through which to identify and study the evolution of variations in social inequalities across age, period, and cohort temporal dimensions. Accordingly, this model should be broadly applicable to the study of social inequality in many different substantive contexts. PMID:22904570