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Sample records for stability study cape

  1. Strategies GeoCape Intelligent Observation Studies @ GSFC

    Science.gov (United States)

    Cappelaere, Pat; Frye, Stu; Moe, Karen; Mandl, Dan; LeMoigne, Jacqueline; Flatley, Tom; Geist, Alessandro

    2015-01-01

    This presentation provides information a summary of the tradeoff studies conducted for GeoCape by the GSFC team in terms of how to optimize GeoCape observation efficiency. Tradeoffs include total ground scheduling with simple priorities, ground scheduling with cloud forecast, ground scheduling with sub-area forecast, onboard scheduling with onboard cloud detection and smart onboard scheduling and onboard image processing. The tradeoffs considered optimzing cost, downlink bandwidth and total number of images acquired.

  2. Thermal stability of phytochemicals, HMF and antioxidant activity in cape gooseberry (Physalis peruviana L.)

    NARCIS (Netherlands)

    Olivares-Tenorio, Mary Luz; Verkerk, Ruud; Boekel, van Tiny; Dekker, Matthijs

    2017-01-01

    Cape gooseberry is a fruit recognised for having relevant contents of health-promoting compounds. Changes in the content of phytochemicals (ascorbic acid, β-carotene, catechin and epicatechin), hydroxymethylfurfural (HMF) and antioxidant activity of this fruit were studied at various temperatures

  3. Virological studies of water from the Cape Flats reclamation plant

    African Journals Online (AJOL)

    The Department of Water Affairs recently published its policy on the management of the water resources of the RSA. I This provides an outline of the expected population growth as well as the demand for potable water in the Cape Town area. The studies have shown that all known fresh-water supplies will be fully committed ...

  4. Eastern Cape hybrid mini-grid systems - a case study

    CSIR Research Space (South Africa)

    Szewczuk, S

    2010-05-01

    Full Text Available -GRID SYSTEMS A CASE STUDY WIND POWER AFRICA 2010 S Szewczuk CSIR May 2010 PRESENTATION OUTLINE • Rationale for Projects • Renewable Energy for Rural Electrification in E Cape • Integrated Energy/Economic Framework • Hybrid mini-grid energy systems... investigated: wind, mini-hydro & biomass • Geographic Information Systems (GIS) to present & interpret results • Output: identification of implementable projects – emphasis on objective technological evaluations Wind assessment at 60 m height Example...

  5. Community-based tourism in Cape Verde - a case study

    OpenAIRE

    Tomas Lopez-Guzman; Osvaldo Borges; Ana Maria Castillo-Canalejo

    2011-01-01

    Community-based tourism is taking its place in the world as an alternative to traditional tourist destinations, especially in developing countries. This form of tourism allows for greater contact with the local community and for the tourist to experience new sensations while enabling the economic and social development of the geographic area. In this paper, the results of fieldwork carried out in the island of Fogo (Cape Verde) are presented, assessing the opinion and perception tourists visi...

  6. Geotourism, Medical Geology and local development: Cape Verde case study

    Science.gov (United States)

    Rocha, F.; Ferreira da Silva, E.

    2014-11-01

    Geotourism and Geoparks in particular are real opportunities to rural developments promoting the rate decline of unemployment and emigration through engaging the local communities in geopark activities and tourism marketing in the form of adventure tourism, ecotourism, rural tourism and health geotourism. Geotourism is closely linked with Medical Geology. The intake of minerals and chemical elements for food, water, soil (through geophagy) or dust can be accomplished by ingestion, inhalation or dermal absorption. Pelotherapy or “Mudtherapy” is the use of mud/clay for therapeutic applications, internal or external. Cape Verde archipelago is located in Atlantic ocean, 400 km westwards of Senegal coast. Geotourism is being developed, mainly focused on the development of a geopark in Fogo island huge caldera, but also trying to take advantage of their potentialities for Geomedecine. A cooperative program established between Cape Verde University (UCV) and Aveiro University (UA, Portugal) is under way, aiming, on a first stage, to identify Geotouristic potentialities and, on a second stage, to develop products. Geotourism is being developed, mainly focused on the development of a geopark in Fogo isl. huge caldera, but also trying to take advantage of their potentialities for Geomedecine.

  7. Private sector community forestry partnerships in the Eastern Cape – Lambazi case study

    CSIR Research Space (South Africa)

    Sisitka, L

    2000-01-01

    Full Text Available This Umzimkulu case study forms part of a broader investigation into community – private sector forestry partnerships in the Eastern Cape. This provincial study in turn, contributes to one of the three major research themes of a wider national...

  8. Homework Policy Review: A Case Study of A Public School in the Western Cape Province

    Science.gov (United States)

    Pfeiffer, Verbra

    2018-01-01

    A key concern today is the question of homework in our nation's public schools. In this study, an investigation was conducted with the first no-homework policy, which has been introduced in one of the primary schools in the Western Cape. This study seeks to determine whether a no-homework policy will validate a positive or negative effect on…

  9. Wave refraction in relation to beach stability along the coast from Cape Ramas to Karwar

    Digital Repository Service at National Institute of Oceanography (India)

    Gouveia, A.D.; Joseph, P.S.; Kurup, P.G.

    Results of wave refraction and beach profile studies are presented for a stretch of 35 km shore line comprising of Loliem Beach, Karwar, Karnataka, India which is separated by rock promontories from comparatively stable beaches on either side of it...

  10. Food Fortification Stability Study

    Science.gov (United States)

    Abdulmalik, T. O.; Cooper, M. R.; Douglas, G. L.

    2015-01-01

    NASA has established the goal of traveling beyond low-Earth orbit and extending manned exploration to Mars. The extended length of a Mars mission, along with the lack of resupply missions increases the importance of nutritional content in the food system. The purpose of this research is to assess the stability of vitamin supplementation in traditionally processed spaceflight foods. It is expected that commercially available fortificants will remain stable through long-duration missions if proper formulation, processing, and storage temperatures are all achieved. Five vitamins (vitamin E, vitamin K, pantothenic acid, folic acid, and thiamin) were blended into a vitamin premix (DSM, Freeport, TX); premixes were formulated to be compatible with current processing techniques (retort or freeze-dried), varied water activities (high or low), and packaging material. The overall goal of this process is to provide 25% of the recommended daily intake of each vitamin (per serving), following processing and two years of ambient storage. Four freeze-dried foods (Scrambled Eggs, Italian Vegetables, Potatoes Au Gratin, Noodles and Chicken) and four thermostabilized foods (Curry Sauce with Vegetables, Chicken Noodle Soup, Grilled Pork Chop, Rice with Butter) were produced (with and without the vitamin premix), to assess the impact of the added fortificant on color and taste, and to determine the stability of supplemental vitamins in spaceflight foods. The use of fortification in spaceflight foods appears to be a plausible mitigation step to inadequate nutrition. This is due to the ease of vitamin addition as well as the sustainability of the premixes through initial processing steps. Postprocessing analysis indicated that vitamin fortification with this premix did not immediately impact organoleptic properties of the food. At this stage, the largest hurdle to fortification is the preciseness to which vitamins can be added; the total amount of vitamins required for production is 10

  11. Food Fortification Stability Study

    Science.gov (United States)

    Sirmons, T.; Cooper, M.; Douglas, G.

    2017-01-01

    NASA has established the goal of traveling beyond low-Earth orbit and extending manned exploration to Mars. The length of proposed Mars missions and the lack of resupply missions increases the importance of nutritional content in the food system, which will need a five-year shelf life. The purpose of this research is to assess the stability of vitamin supplementation in traditionally processed spaceflight foods. It is expected that commercially available fortification nutrients will remain stable through a long duration exploration mission at sufficient levels if compatible formulation, processing, and storage temperatures are achieved. Five vitamins (vitamin E, vitamin K, pantothenic acid, folic acid, and thiamin) were blended into a vitamin premix (DSM, Freeport, TX) such that the vitamin concentration per serving equaled 25% of the recommended daily intake after two years of ambient storage. Four freeze-dried foods (Scrambled Eggs, Italian Vegetables, Potatoes Au Gratin, Noodles and Chicken) and four thermo-stabilized foods (Curry Sauce with Vegetables, Chicken Noodle Soup, Grilled Pork Chop, Rice with Butter) were produced, with and without the vitamin premix, to assess the impact of the added fortification on color and taste and to determine the stability of supplemental vitamins in spaceflight foods. The addition of fortification to spaceflight foods did not greatly alter the organoleptic properties of most products. In most cases, overall acceptability scores remained above 6.0 (minimum acceptable score) following six months and one year of low-temperature storage. Likewise, the color of fortified products appears to be preserved over one year of storage. The only exceptions were Grilled pork Chop and Chicken Noodle Soup whose individual components appeareddegrade rapidly over one year of storage. Finally, most vitamins appeared to be stable during long-term storage. The only exception was thiamin, which degraded rapidly during the first year of storage at

  12. Planning Study Hospital, Cape Town The Hospital Information at ...

    African Journals Online (AJOL)

    dent of Groote Schuur Hospital, commissioned the Hospital. Information Planning Study (HIPS) in the belief that modern information management techniques and existing computer technology can be of considerable benefit in dealing with these issues. The objectives of the HIPS included a review of the existing information ...

  13. Pilot study of a culturally adapted psychoeducation (CaPE) intervention for bipolar disorder in Pakistan.

    Science.gov (United States)

    Husain, Muhammad Ishrat; Chaudhry, Imran B; Rahman, Raza R; Hamirani, Munir M; Mehmood, Nasir; Haddad, Peter M; Hodsoll, John; Young, Allan H; Naeem, Farooq; Husain, Nusrat

    2017-12-01

    Despite the use of maintenance medication, recurrence rates in bipolar affective disorder (BPAD) are high. To date, there are no clinical trials that have investigated the use of psychological interventions in bipolar disorder in Pakistan. The purpose of the study was to assess the feasibility and acceptability of a culturally adapted bipolar psychoeducation programme (CaPE) in Pakistan. Thirty-four euthymic bipolar I and II outpatients were randomized to either 12 weekly sessions of individual psychoeducation plus Treatment As Usual (Intervention) or Treatment As Usual (TAU) (Control). Outcomes were assessed using the Young Mania Rating Scale (YMRS), Beck Depression Inventory (BDI), EuroQoL (EQ-5D), Bipolar Knowledge and Attitudes and Questionnaire (BKAQ), and a self-reported measure of medication adherence (Morisky Medication Adherence Scale-4 items, MMAS-4). Effect sizes were derived from baseline adjusted standardized regression coefficients. Retention in the study was good, 80% of patients in the TAU follow-up assessment and 100% of patients in the CaPE group attended all 12 sessions. Patient satisfaction was higher in the CaPE group relative to control (ES = 1.41). Further, there were large effect sizes shown for CaPE versus TAU for medication adherence (MMAS-4: ES = 0.81), knowledge and attitudes towards bipolar (BKAQ: ES = 0.68), mania (YMRS: ES = 1.18), depression (BDI: ES = 1.17) and quality of life measures (EQ-5D: ES ⇒ 0.88). Culturally adapted psychoeducation intervention is acceptable and feasible, and can be effective in improving mood symptoms and knowledge and attitudes to BPAD when compared with TAU. Larger scale studies are needed to confirm our findings. Clinicaltrials.gov identifier NCT02210390.

  14. Assessing post apartheid settlement growth patterns using remote sensing and GIWS: A case study of Cape Town metropolitan area

    CSIR Research Space (South Africa)

    Pillay, DL

    2008-11-01

    Full Text Available growth patterns, using remote sensing and GIS: A case study of Cape Town metropolitan area DL PILLAY AND MD SEBAKE Meraka Institute, CSIR, PO Box 395, Pretoria, 0001 Email: dlpillay@csir.co.za – www.csir.co.za Council for Geoscience, Private Bag X... and Gordons Bay. Other land use classes of Open Space to Residential High (9,72%) and Open Space to Residential Informal (8,72 %) were more evident on both sides of the N2 highway in the vicinity of Cape Town International Airport and Cape Flats...

  15. Applicability of satellite rainfall estimates for erosion studies in small offshore areas: a case study in Cape Verde Islands

    NARCIS (Netherlands)

    Moreno, J.F.S.; Mannaerts, C.M.; Jetten, V.G.

    2014-01-01

    To assess the usability of satellite rainfall estimates for erosion studies in Cape Verde, the 3B42 and 3B43 products from TRMM, and the Multi-Sensor Precipitation Estimate MPE from Meteosat are compared to daily and monthly ground rainfall measured between 1998 and 2010. TRMM estimates from 1998

  16. Western Cape Primary Care Assessment Tool (PCAT) study: Measuring primary care organisation and performance in the Western Cape Province, South Africa (2013)

    Science.gov (United States)

    Sayed, Abdul-Rauf; le Grange, Cynthia; Bhagwan, Susheela; Manga, Nayna; Hellenberg, Derek

    2016-01-01

    Background Major health sector reform and the need for baseline measures of performance to determine impact. Aim Baseline audit of primary healthcare (PHC) performance. Setting Cape Town and Cape Winelands (rural) PHC facilities (PCFs) in Western Cape Province, South Africa. Method The South African cross-culturally validated ZA PCAT to audit PHC performance on 11 subdomains associated with improved health and reduced costs. Adult PCF users systematically sampled. All full-time doctors and nurse practitioners in PCFs sampled and all PCF managers in sub-districts sampled invited into the study. Results Data from 1432 users, 100 clinicians and 64 managers from 13 PCFs in 10 sub-districts analysed (figures show stakeholder percentages scoring subdomain performance ‘acceptable to good’). 11.5% users scored access ‘acceptable to good’; community orientation and comprehensive services provided 20.8% and 39.9%, respectively. Total PHC score for users 50.2%; for managers and practitioners 82.8% and 88.0%, respectively. Among practitioners access was lowest (33.3%); PHC team (98.0%) and comprehensive services available (100.0%) highest. Among managers, access (13.5%) and family centredness (45.6%) are lowest; PHC team (85.9%) and comprehensive services available (90.6%) highest. Managers scored access, family centredness and cultural competence significantly lower than practitioners. Users scored comprehensive services available, comprehensive services provided and community orientation significantly lower than practitioners and managers. Conclusion Gaps between users’ experience and providers’ assessments of PHC performance are identified. Features that need strengthening and alignment with best practice, provincial and national, and health policies are highlighted with implications for practitioner and manager training, health policy, and research. PMID:27247157

  17. Private sector community forestry partnerships in the Eastern Cape – The Longweni woodlot case study

    CSIR Research Space (South Africa)

    Cocks, M

    2000-01-01

    Full Text Available for sustainable private sector forestry in South Africa. The reports in this series are listed below. Instruments for Sustainable Private Sector Forestry, South Africa – report series Overview and synthesis • Mayers, J., Evans, J. and Foy, T. 2001. Raising.... • Heyl, L., von Maltitz, G., Evans, J. and Segoale, R. 2000. Issues and opportunities for small-scale sawmilling in South Africa: an Eastern Cape case study. This report describes the scale, structure and market niche of the small sawmilling subsector...

  18. [Cape Verde].

    Science.gov (United States)

    The capital of Cape Verde is Praia. As of 1995, Cape Verde had a population of 400,000 governed by a presidential, multiparty regime. 1994 gross national product and per capita income were, respectively, $346 million and $910. Per capita income grew at 1.8% per year over the period 1985-94. In 1994, Cape Verde owed $169.9 million, then being serviced at $11.9 million. For the same year, Cape Verde exported $53 million in goods and services and imported $188 million. As of 1995, the population was growing in size by 5.5% annually. In 1992-93, life expectancy at birth was 64.7 years and the infant mortality rate was 130 per 1000 births. Other data are presented on the country's topography, climate and vegetation, demographics, principal cities, population distribution, religions, political structure, economics and finances, foreign commerce, and transportation and communications.

  19. Cape Town

    African Journals Online (AJOL)

    458 young competitive basketball players in. Cape Town, including 122 club players and 336 school ... account for 12% of total sports injuries, they represent 25% of the total injury cost.” Similarly, knee injuries ... physical activity are well recognised. Although it is advantageous that 23 500 South African school children now.

  20. Methodological challenges in a study on falls in an older population of Cape Town, South Africa.

    Science.gov (United States)

    Kalula, Sebastiana Z; Ferreira, Monica; Swingler, George H; Badri, Motasim; Sayer, Avan A

    2017-09-01

    Falls are a major cause of disability, morbidity and mortality in older persons, but have been under researched in developing countries. To describe challenges encountered in a community-based study on falls in a multi-ethnic population aged ≥65 years in a low-income setting. The study was conducted in four stages: A pilot study (n=105) to establish a sample size for the survey. An equipment validation study (n=118) to use for fall risk determination. A cross-sectional baseline (n=837) and a 12-month follow-up survey (n=632) to establish prevalence and risk factors for falls. Prevalence rate of 26.4% (95% CI 23.5-29.5%) and risk factors for recurrent falls: previous falls, self-reported poor mobility and dizziness were established. Adaptations to the gold standard prospective fall research study design were employed: 1) to gain access to the study population in three selected suburbs, 2) to perform assessments in a non-standardised setting, 3) to address subjects' poverty and low literacy levels, and high attrition of subjects and field workers. Studies on falls in the older population of low- to middle-income countries have methodological challenges. Adaptive strategies used in the Cape Town study and the research experience reported may be instructive for investigators planning similar studies in such settings.

  1. Comparative study of the topography and sediments of the western and eastern continental shelves around Cape Comorin

    Digital Repository Service at National Institute of Oceanography (India)

    Hashimi, N.H.; Kidwai, R.M.; Nair, R.R.

    Western and eastern continental shelves around Cape Comorin show 3 well-defined regions of depositional environments each having its own characteric features. The environments extend from Cochin to Quilon Quilon to Cape Comorin and Cape Comorin...

  2. Interactive simulations for promoting transdisciplinary understanding: a case study of the Western Cape fisheries, South Africa

    Directory of Open Access Journals (Sweden)

    Cecile Proches

    2012-07-01

    Full Text Available Simulations have proven beneficial in enabling participants from various backgrounds to meaningfully engage in learning from experience. The aim of this paper is to investigate how interactive simulations can play a role in navigating the changes faced in a multi- stakeholder setting, characterised by users dependent on marine resources and an authorising institution. Relevant literature in the areas of simulation and gaming, change management, systems thinking, and complexity theory was examined. A qualitative research approach and purposive sampling were employed. Interviews were first conducted with diverse stakeholders in the Western Cape fisheries of South Africa to determine the issues. A simulation was thereafter designed. The main findings from this study indicate that simulation use illustrates how the various stakeholders in a system interact, and how their actions and decisions influence each other. The simulation may be used in other areas of natural resource management, as well as in other kinds of multi- stakeholder scenarios. Keywords: Simulation and gaming, Change management, Fisheries, Multi-stakeholder scenarios, Systems thinking, Complexity theory Disciplines: Conflict Resolution, Leadership Studies, Management Studies, Natural Resource Management

  3. A qualitative study of methamphetamine initiation in Cape Town, South Africa.

    Science.gov (United States)

    Hobkirk, Andréa L; Watt, Melissa H; Myers, Bronwyn; Skinner, Donald; Meade, Christina S

    2016-04-01

    Despite a significant rise in methamphetamine use in low- and middle-income countries, there has been little empirical examination of the factors that contribute to individuals' initiation of methamphetamine use in these settings. The goal of this study was to qualitatively examine factors associated with methamphetamine initiation in South Africa. In-depth interviews were conducted with 30 active methamphetamine users (13 women and 17 men) in Cape Town, South Africa. Interviews included narrative descriptions of the circumstances surrounding methamphetamine initiation. Interviews were audio recorded, transcribed, and translated. Transcripts were analyzed with document memos, data display matrices, and a constant comparison technique to identify themes. On average, participants began regularly using methamphetamine around age 21 and had used for seven years. Four major themes emerged related to the initiation of methamphetamine use. The prevalence of methamphetamine users and distributors made the drug convenient and highly accessible to first time users. Methamphetamine has increased in popularity and is considered "trendy", which contributes to social pressure from friends, and less often, family members to initiate use. Initiation is further fueled by a lack of opportunities for recreation and employment, which leads to boredom and curiosity about the rumored positive effects of the drug. Young people also turn to methamphetamine use and distribution through gang membership as an attempt to generate income in impoverished communities with limited economic opportunities. Finally, participants described initiating methamphetamine as a means of coping with the cumulative stress and psychological burden provoked by the high rates of violence and crime in areas of Cape Town. The findings highlight the complex nature of methamphetamine initiation in low- and middle-income countries like South Africa. There is a need for community-level interventions to address the

  4. Enabling disability inclusive practices within the University of Cape Town curriculum: A case study

    Science.gov (United States)

    Ohajunwa, Chioma

    2015-01-01

    Background Disability inclusion in the curricula of higher education institutions contributes to socially responsive graduates with a capacity to address the cross-cutting issue of disability in development. This article discusses a study conducted at the University of Cape Town (UCT), South Africa, to explore disability inclusion. Methodology An instrumental case study approach was adopted and a thematic analysis of data was done. Findings Academic staff found a variety of ways to include disability, such as discussions in class, practice and service learning, but mainly as part of disciplinary requirements. Including disability as an issue of social justice stems mostly from the personal interest of staff, and is done in an ad hoc manner. Conclusion Disability should be valued, and integrated into the curriculum in a structured manner as a perspective on diversity with which to interrogate our beliefs about ourselves and society. Theorising on disability is needed, as well as the unique perspectives that emerge across interdisciplinary boundaries, especially within the African context. PMID:28730025

  5. Enabling disability inclusive practices within the University of Cape Town curriculum: A case study

    Directory of Open Access Journals (Sweden)

    Chioma Ohajunwa

    2015-02-01

    Full Text Available Background: Disability inclusion in the curricula of higher education institutions contributes to socially responsive graduates with a capacity to address the cross-cutting issue of disability in development. This article discusses a study conducted at the University of Cape Town (UCT, South Africa, to explore disability inclusion. Methodology: An instrumental case study approach was adopted and a thematic analysis of data was done. Findings: Academic staff found a variety of ways to include disability, such as discussions in class, practice and service learning, but mainly as part of disciplinary requirements. Including disability as an issue of social justice stems mostly from the personal interest of staff, and is done in an ad hoc manner. Conclusion: Disability should be valued, and integrated into the curriculum in a structured manner as a perspective on diversity with which to interrogate our beliefs about ourselves and society. Theorising on disability is needed, as well as the unique perspectives that emerge across interdisciplinary boundaries, especially within the African context.

  6. Enabling disability inclusive practices within the University of Cape Town curriculum: A case study

    Directory of Open Access Journals (Sweden)

    Chioma Ohajunwa

    2015-07-01

    Full Text Available Background: Disability inclusion in the curricula of higher education institutions contributes to socially responsive graduates with a capacity to address the cross-cutting issue of disability in development. This article discusses a study conducted at the University of Cape Town (UCT, South Africa, to explore disability inclusion. Methodology: An instrumental case study approach was adopted and a thematic analysis of data was done. Findings: Academic staff found a variety of ways to include disability, such as discussions in class, practice and service learning, but mainly as part of disciplinary requirements. Including disability as an issue of social justice stems mostly from the personal interest of staff, and is done in an ad hoc manner. Conclusion: Disability should be valued, and integrated into the curriculum in a structured manner as a perspective on diversity with which to interrogate our beliefs about ourselves and society. Theorising on disability is needed, as well as the unique perspectives that emerge across interdisciplinary boundaries, especially within the African context.

  7. Unaccompanied and Separated Foreign Children in the Care System in the Western Cape – A Socio-Legal Study

    Directory of Open Access Journals (Sweden)

    Julia Sloth-Nielsen

    2016-05-01

    Full Text Available This article reports on the findings of a study of foreign children accommodated in the care system in the Western Cape, based on fieldwork conducted in child and youth care centres. The objectives of the study were firstly to map and quantify the number and demographics of foreign children placed in all CYCCs across the Western Cape. Secondly, the study aimed to analyse the reasons for children's migration and the circumstances around their placement in residential care institutions in order to establish whether family reunification was possible or desirable. Thirdly, the study explores the sufficiency of efforts made to trace and reunify the children with their families, whether in South Africa or across borders, as the institutional placement of children should not only be a last resort but it should preferably be temporary whilst family-based solutions are sought. Lastly, the documentation status of the children in the study was examined. Recommendations emanating from the research conclude the study.

  8. Shallow Water Habitat Mapping in Cape Cod National Seashore: A Post-Hurricane Sandy Study

    Science.gov (United States)

    Borrelli, M.; Smith, T.; Legare, B.; Mittermayr, A.

    2017-12-01

    Hurricane Sandy had a dramatic impact along coastal areas in proximity to landfall in late October 2012, and those impacts have been well-documented in terrestrial coastal settings. However, due to the lack of data on submerged marine habitats, similar subtidal impact studies have been limited. This study, one of four contemporaneous studies commissioned by the US National Park Service, developed maps of submerged shallow water marine habitats in and around Cape Cod National Seashore, Massachusetts. All four studies used similar methods of data collection, processing and analysis for the production of habitat maps. One of the motivations for the larger study conducted in the four coastal parks was to provide park managers with a baseline inventory of submerged marine habitats, against which to measure change after future storm events and other natural and anthropogenic phenomena. In this study data from a phase-measuring sidescan sonar, bottom grab samples, seismic reflection profiling, and sediment coring were all used to develop submerged marine habitat maps using the Coastal and Marine Ecological Classification Standard (CMECS). Vessel-based acoustic surveys (n = 76) were conducted in extreme shallow water across four embayments from 2014-2016. Sidescan sonar imagery covering 83.37 km2 was collected, and within that area, 49.53 km2 of co-located bathymetric data were collected with a mean depth of 4.00 m. Bottom grab samples (n = 476) to sample macroinvertebrates and sediments (along with other water column and habitat data) were collected, and these data were used along with the geophysical and coring data to develop final habitat maps using the CMECS framework.

  9. Ozone and radon at Cape Grim: A study of their interdependence

    International Nuclear Information System (INIS)

    Zahorowski, W.; Galbally, I.E.; Meyer, C.P.

    1996-01-01

    A discussion of the ozone and radon variations at Cape Grim, Tasmania, and their interdependence is presented. The use of radon concentration as a criterion for baseline conditions ( - 3) results in a baseline data set that has a smaller range of concentrations within each month than that obtained using wind speed and direction as baseline criteria. The passage of cold fronts at Cape Grim is associated with a change in air flow from the continent to the Southern Ocean. Comparison of radon, wind direction and ozone during these events indicates that continental air continues arriving at Cape Grim for several hours after passage of the front and the establishment of the air flow from the baseline sector. This confirms that use of the speed and direction is not necessarily a good method of defining baseline conditions for ozone. When air comes to Cape Grim form over the Tasmanian land surface during those times of the year when (due to solar radiation and temperature) the probability of ozone production is low, the ozone and radon concentrations observed are negatively correlated. A simple model of ozone destruction at the Earth's surface and radon emission from the surface quantitatively describes these observations. (author). 1 tab., 5 figs., 6 refs

  10. Characteristics and outcome of children with juvenile dermatomyositis in Cape Town: a cross-sectional study.

    Science.gov (United States)

    Okong'o, Lawrence Owino; Esser, Monika; Wilmshurst, Jo; Scott, Christiaan

    2016-11-11

    Juvenile dermatomyositis (JDM) is a rare idiopathic inflammatory childhood myopathy of uncertain aetiology. The demographic and clinical presentation of JDM may differ by race and geographic regions. Few studies have described the characteristics of JDM patients from Africa. We conducted a retrospective observational study to determine clinical characteristics and outcomes of patients satisfying the Bohan and Peter criteria for probable JDM seen between 2004 and 2013 in three hospitals in Cape Town, South Africa. Twenty five cases were identified: 16 female and 9 male; thirteen (52 %) were of indigenous African, eleven (44 %) mixed and one (4 %) European ancestry. The median ages at disease onset and diagnosis were 6.75 (range 2.0-9.7) and 7.9 (range 3.4-9.75) years respectively. Eleven patients had calcinosis while the mortality was 2/25 (8 %). Only 40 % of the patients had clinically inactive disease by PRINTO criteria (modified) at last review. There was no statistically significant difference in racial distribution (p-value = 1), age at disease onset (p-value = 0.87) and disease duration prior to treatment initiation (p-value = 0.75) between patients who had clinically active and inactive disease. The demographic characteristics of children with JDM were similar to that from most other regions of the world with female predominance and similar age at onset. Majority of the patients remained with clinically active disease, which put them at risk of further disease complications. Long term follow up and use of appropriate treatment guidelines may be indicated in management of JDM patients for optimum treatment outcomes.

  11. Demand Constraints and New Demands: Regulations, Markets and Institutions Efficiency (A Case Study for Cape Verde

    Directory of Open Access Journals (Sweden)

    Bernardo Reynolds Pacheco de Carvalho

    2014-08-01

    Full Text Available Economic efficiency is a key issue in economic research and for policy design, and certainly for food security challenges. In the food system dynamics the understanding of changes and trends is crucial to improve our capacity to deal with the objectives of sustainable development and quality of life. Food system efficiency evaluation is necessary with regard to production and consumption efficiencies as well as market and governance dilemmas. Regulations and institutional efficiency are crucial aspects that are frequently forgotten, and efforts should be made to improve the capacity to deal with those methodological needs. In many situations, in the real world, data and measurements are difficult or even impossible to get in numeric or quantitative terms. Frequently, a qualitative evaluation is the only way to proceed, but measurements and numeric references are still important, mainly when changes over time are central to the research. The actual paper follows a structural food system model (WFSE – World Food Security Equation and a general equilibrium approach (ICI model – induced changes and innovation model to show in a country case study (Cape Verde the important role of markets and institutions as compared to regulation practices directed to improve economic efficiency subject to demand behavior. Cape Verde is a very challenging country with regard to the food security status (where natural resources are very poor for agricultural production but with great success in global and macro terms in the last 10 years. The main problems nowadays are clearly at local level. The present research tries to highlight the global achievements and explore local assessment efforts on food consumption conditions. A specific region is studied, in the island of Santo Antão, one of the most important production regions. Three different production systems were compared mainly with regard to their respective influence on consumption habits, incomes and

  12. Secondary Education and Health Outcomes in Young People from the Cape Area Panel Study (CAPS)

    Science.gov (United States)

    2016-01-01

    Aim Education is one of the strongest social determinants of health, yet previous literature has focused on primary education. We examined whether there are additional benefits to completing upper secondary compared to lower secondary education in a middle-income country. Methods We performed a longitudinal analysis of the Cape Area Panel Study, a survey of adolescents living in South Africa. We undertook causal modeling using structural marginal models to examine the association between level of education and various health outcomes, using inverse probability weighting to control for sex, age, ethnicity, home language, income, whether employed in past year, region of birth, maternal educational status, marital status, whether currently pregnant and cognitive ability. Educational attainment was defined as primary (grades 1–7), lower secondary (grades 8–9) or upper secondary (grades 10–12). Results Of 3,432 participants, 165 (4.8%) had completed primary education, 646 (18.8%) lower secondary and 2,621 (76.3%) upper secondary. Compared to those completing lower secondary, males completing upper secondary education were less likely to have a health problem (OR 0.49; 95%CI 0.27–0.88; p = 0.02); describe their health as poor (0.52; 0.29–0.95; p = 0.03) or report that health interferes with daily life (0.54; 0.29–0.99; p = 0.047). Females were less likely to have been pregnant (0.45; 0.33–0.61; peducation and alcohol use, psychological distress, obesity, increased waist circumference or hypertension. Conclusion Completing upper secondary education was associated with improved health outcomes compared with lower secondary education. Expanding upper secondary education offers middle-income countries an effective way of improving adolescent health. PMID:27280408

  13. Secondary Education and Health Outcomes in Young People from the Cape Area Panel Study (CAPS).

    Science.gov (United States)

    Ward, Joseph L; Viner, Russell M

    2016-01-01

    Education is one of the strongest social determinants of health, yet previous literature has focused on primary education. We examined whether there are additional benefits to completing upper secondary compared to lower secondary education in a middle-income country. We performed a longitudinal analysis of the Cape Area Panel Study, a survey of adolescents living in South Africa. We undertook causal modeling using structural marginal models to examine the association between level of education and various health outcomes, using inverse probability weighting to control for sex, age, ethnicity, home language, income, whether employed in past year, region of birth, maternal educational status, marital status, whether currently pregnant and cognitive ability. Educational attainment was defined as primary (grades 1-7), lower secondary (grades 8-9) or upper secondary (grades 10-12). Of 3,432 participants, 165 (4.8%) had completed primary education, 646 (18.8%) lower secondary and 2,621 (76.3%) upper secondary. Compared to those completing lower secondary, males completing upper secondary education were less likely to have a health problem (OR 0.49; 95%CI 0.27-0.88; p = 0.02); describe their health as poor (0.52; 0.29-0.95; p = 0.03) or report that health interferes with daily life (0.54; 0.29-0.99; p = 0.047). Females were less likely to have been pregnant (0.45; 0.33-0.61; psex under 16 was also less likely (males 0.63; 0.44-0.91; p = 0.01; females 0.39; 0.26-0.58; peducation and alcohol use, psychological distress, obesity, increased waist circumference or hypertension. Completing upper secondary education was associated with improved health outcomes compared with lower secondary education. Expanding upper secondary education offers middle-income countries an effective way of improving adolescent health.

  14. Health activism in Cape Town: a case study of the Health Workers Society.

    Science.gov (United States)

    Pick, W; Claassen, J W B; Le Grange, C A; Hussey, G D

    2012-03-02

    The Health Workers Society (HWS), founded in 1980, was one of several progressive health organisations that fought for a democratic health system in South Africa. We document the sociopolitical context within which it operated and some of its achievements. HWS, many of whose members were staff and students of the University of Cape Town (UCT), provided a forum for debate on health-related issues, politics and society, and worked closely with other organisations to oppose the apartheid state's health policies and practices. They assisted with the formation of the first dedicated trade union for all healthcare workers and were one of the first to pioneer the primary healthcare approach in an informal settlement in Cape Town.

  15. An 40 Ar- 39 Ar study of the Cape Verde hot spot

    DEFF Research Database (Denmark)

    Holm, Paul Martin; Grandvuinet, Tanja; Wilson, James Richard

    2008-01-01

    The 40Ar-39Ar analyses of 28 groundmass separates from volcanic rocks from the islands of Santiago, Sal, and São Vicente, Cape Verde archipelago, are presented. The new age data record the volcanic evolution for Santiago from 4.6 to 0.7 Ma, for Sal from around 15 to 1.1 Ma, and for São Vicente from...

  16. Women's experiences seeking informal sector abortion services in Cape Town, South Africa: a descriptive study.

    Science.gov (United States)

    Gerdts, Caitlin; Raifman, Sarah; Daskilewicz, Kristen; Momberg, Mariette; Roberts, Sarah; Harries, Jane

    2017-10-02

    In settings where abortion is legally restricted, or permitted but not widely accessible, women face significant barriers to abortion access, sometimes leading them to seek services outside legal facilities. The advent of medication abortion has further increased the prevalence of informal sector abortion. This study investigates the reasons for attempting self-induction, methods used, complications, and sources of information about informal sector abortion, and tests a specific recruitment method which could lead to improved estimates of informal sector abortion prevalence among an at-risk population. We recruited women who have sought informal sector abortion services in Cape Town, South Africa using respondent driven sampling (RDS). An initial seed recruiter was responsible for initiating recruitment using a structured coupon system. Participants completed face-to-face questionnaires, which included information about demographics, informal sector abortion seeking, and safe abortion access needs. We enrolled 42 women, nearly one-third of whom reported they were sex workers. Thirty-four women (81%) reported having had one informal sector abortion within the past 5 years, 14% reported having had two, and 5% reported having had three. These women consumed home remedies, herbal mixtures from traditional healers, or tablets from an unregistered provider. Twelve sought additional care for potential warning signs of complications. Privacy and fear of mistreatment at public sector facilities were among the main reported reasons for attempting informal sector abortion. Most women (67%) cited other community members as their source of information about informal sector abortion; posted signs and fliers in public spaces also served as an important source of information. Women are attempting informal sector abortion because they seek privacy and fear mistreatment and stigma in health facilities. Some were unaware how or where to seek formal sector services, or believed the

  17. Morphological characteristics of Cape sugarbirds ( Promerops cafer ...

    African Journals Online (AJOL)

    Cape sugarbirds (Promerops cafer) are the largest nectarivores in the Western Cape and feed almost exclusively on protea nectar and associated arthropods. Helderberg Nature Reserve, Western Cape, South Africa, has a large diversity of Protea and supports breeding sugarbirds. As part of a larger study, we captured ...

  18. Secondary Education and Health Outcomes in Young People from the Cape Area Panel Study (CAPS.

    Directory of Open Access Journals (Sweden)

    Joseph L Ward

    Full Text Available Education is one of the strongest social determinants of health, yet previous literature has focused on primary education. We examined whether there are additional benefits to completing upper secondary compared to lower secondary education in a middle-income country.We performed a longitudinal analysis of the Cape Area Panel Study, a survey of adolescents living in South Africa. We undertook causal modeling using structural marginal models to examine the association between level of education and various health outcomes, using inverse probability weighting to control for sex, age, ethnicity, home language, income, whether employed in past year, region of birth, maternal educational status, marital status, whether currently pregnant and cognitive ability. Educational attainment was defined as primary (grades 1-7, lower secondary (grades 8-9 or upper secondary (grades 10-12.Of 3,432 participants, 165 (4.8% had completed primary education, 646 (18.8% lower secondary and 2,621 (76.3% upper secondary. Compared to those completing lower secondary, males completing upper secondary education were less likely to have a health problem (OR 0.49; 95%CI 0.27-0.88; p = 0.02; describe their health as poor (0.52; 0.29-0.95; p = 0.03 or report that health interferes with daily life (0.54; 0.29-0.99; p = 0.047. Females were less likely to have been pregnant (0.45; 0.33-0.61; p<0.001 or pregnant under 18 (0.32; 0.22-0.46; p<0.001; and having had sex under 16 was also less likely (males 0.63; 0.44-0.91; p = 0.01; females 0.39; 0.26-0.58; p<0.001. Cigarette smoking was less likely (males 0.52; 0.38-0.70; p = <0.001; females 0.56; 0.41-0.76; p<0.001, as was taking illicit drugs in males (0.6; 0.38-0.96; p = 0.03. No associations were found between education and alcohol use, psychological distress, obesity, increased waist circumference or hypertension.Completing upper secondary education was associated with improved health outcomes compared with lower secondary

  19. Cape fearless.

    Science.gov (United States)

    1998-01-01

    This article describes the Ilita Labantu (IL) group in South Africa, that is working to reduce child abuse and violence against women. The group started in 1989, with the aim of reducing child rape and sexual assaults in five townships in Cape Town. Child rape is perpetuated by myths sustained by witch doctors and indigenous medicine that promote child rape as a cure-all for symptoms ranging from poverty to AIDS. IL has four satellite groups that educate rape and abuse victims and potential victims. It is assumed that girls are potential victims because of their early unawareness that gender is tied to some patterns of behavior. IL trained mass media groups to educate the general public. IL distributes public information materials on how to identify domestic violence and abuse and how to identify potential rapists within households. Materials are distributed to individuals in community programs and in training programs. Child survivors make presentations in playgroups in a nonthreatening way. IL interacts with courts of law, police stations, hospitals, and schools. The group refers 25-35 cases per day. The group is working on setting up private rooms in police stations where rape victims can make confidential complaints without public attention. IL also works to promote the use of alternative strategies for solving family conflicts.

  20. Some ecological studies of the lower Cape Fear River Estuary, ocean outfall, and Dutchman Creek, 1971

    International Nuclear Information System (INIS)

    Copeland, B.J.; Birkhead, W.S.

    1972-01-01

    A survey of the hydrography and biological components of the Cape Fear River Estuary and nearshore ocean off Oak Island was conducted. Species diversity indices were computed from nekton samples and phytoplankton, zooplankton, and benthos samples are being analysed. A computer program was developed whereby data were alphabetized by species, sorted by location, station, and date, and printed. Experiments were conducted to determine the Critical Thermal Maximum of shrimp. Measurements were made on water temperature, salinity, and dissolved oxygen from June through October. (U.S.)

  1. ASSESSING SPATIAL DATA QUALITY OF PARTICIPATORY GIS STUDIES: A CASE STUDY IN CAPE TOWN

    Directory of Open Access Journals (Sweden)

    K. Musungu

    2015-10-01

    Full Text Available Participatory GIS (PGIS has been prescribed by scholars who sought to find a means to enable more equitable access to GIS data, diversifying the types of knowledge captured by a GIS and re-engineering GIS software. The popularity of PGIS is evident in the various studies and contexts in which it has been utilised. These include studies in risk assessment, land administration, resource management, crime mapping and urban design to mention but a few. Despite the popularity of PGIS as a body of research, little has been done in the analysis of the quality of PGIS information. The study investigated the use of data quality criteria commonly used in traditional GIS systems and shows that it is possible to apply the criteria used in traditional GIS to PGIS. It provides a starting point for PGIS studies to assess the quality of the product. Notably, this a reflective exercise on one case study, but the methodologies used in this study have been replicated in many others undertaken by Community Based Organisations as well as Non-Governmental Organisations. Therefore the findings are relevant to such projects.

  2. Assessing Spatial Data Quality of Participatory GIS Studies: a Case Study in Cape Town

    Science.gov (United States)

    Musungu, K.

    2015-10-01

    Participatory GIS (PGIS) has been prescribed by scholars who sought to find a means to enable more equitable access to GIS data, diversifying the types of knowledge captured by a GIS and re-engineering GIS software. The popularity of PGIS is evident in the various studies and contexts in which it has been utilised. These include studies in risk assessment, land administration, resource management, crime mapping and urban design to mention but a few. Despite the popularity of PGIS as a body of research, little has been done in the analysis of the quality of PGIS information. The study investigated the use of data quality criteria commonly used in traditional GIS systems and shows that it is possible to apply the criteria used in traditional GIS to PGIS. It provides a starting point for PGIS studies to assess the quality of the product. Notably, this a reflective exercise on one case study, but the methodologies used in this study have been replicated in many others undertaken by Community Based Organisations as well as Non-Governmental Organisations. Therefore the findings are relevant to such projects.

  3. Unmatched Case-Control Study on Late Presentation of HIV Infection in Santiago, Cape Verde (2004-2011).

    Science.gov (United States)

    Moreira, António L; Fronteira, Inês; Augusto, Gonçalo Figueiredo; Martins, Maria Rosario O

    2016-03-15

    Access to free antiretroviral therapy (ART) in Sub-Saharan Africa has been steadily increasing over the past decade. However, the success of large-scale ART programmes depends on timely diagnosis and early initiation of HIV care. This study characterizes late presenters to HIV care in Santiago (Cape Verde) between 2004 and 2011, and identifies factors associated with late presentation for care. We defined late presentation as persons presenting to HIV care with a CD4 count below 350 cells/mm³. An unmatched case-control study was conducted using socio-demographic and behavioural data of 368 individuals (191 cases and 177 controls) collected through an interviewer-administered questionnaire, comparing HIV patients late and early presented to care. Logistic regression was performed to estimate odds ratio and 95% confidence intervals. Results show that 51.9% were late presenters for HIV. No differences were found in gender distribution, marital status, or access to health services between cases and controls. Participants who undertook an HIV test by doctor indication were more likely to present late compared with those who tested for HIV by their own initiative. Also, individuals taking less time to initiate ART are more likely to present late. This study highlights the need to better understand reasons for late presentation to HIV care in Cape Verde. People in older age groups should be targeted in future approaches focused on late presenters to HIV care.

  4. Unmatched Case-Control Study on Late Presentation of HIV Infection in Santiago, Cape Verde (2004–2011)

    Science.gov (United States)

    Moreira, António L.; Fronteira, Inês; Augusto, Gonçalo Figueiredo; Martins, Maria Rosario O.

    2016-01-01

    Access to free antiretroviral therapy (ART) in Sub-Saharan Africa has been steadily increasing over the past decade. However, the success of large-scale ART programmes depends on timely diagnosis and early initiation of HIV care. This study characterizes late presenters to HIV care in Santiago (Cape Verde) between 2004 and 2011, and identifies factors associated with late presentation for care. We defined late presentation as persons presenting to HIV care with a CD4 count below 350 cells/mm3. An unmatched case-control study was conducted using socio-demographic and behavioural data of 368 individuals (191 cases and 177 controls) collected through an interviewer-administered questionnaire, comparing HIV patients late and early presented to care. Logistic regression was performed to estimate odds ratio and 95% confidence intervals. Results show that 51.9% were late presenters for HIV. No differences were found in gender distribution, marital status, or access to health services between cases and controls. Participants who undertook an HIV test by doctor indication were more likely to present late compared with those who tested for HIV by their own initiative. Also, individuals taking less time to initiate ART are more likely to present late. This study highlights the need to better understand reasons for late presentation to HIV care in Cape Verde. People in older age groups should be targeted in future approaches focused on late presenters to HIV care. PMID:26999167

  5. Unmatched Case-Control Study on Late Presentation of HIV Infection in Santiago, Cape Verde (2004–2011

    Directory of Open Access Journals (Sweden)

    António L. Moreira

    2016-03-01

    Full Text Available Access to free antiretroviral therapy (ART in Sub-Saharan Africa has been steadily increasing over the past decade. However, the success of large-scale ART programmes depends on timely diagnosis and early initiation of HIV care. This study characterizes late presenters to HIV care in Santiago (Cape Verde between 2004 and 2011, and identifies factors associated with late presentation for care. We defined late presentation as persons presenting to HIV care with a CD4 count below 350 cells/mm3. An unmatched case-control study was conducted using socio-demographic and behavioural data of 368 individuals (191 cases and 177 controls collected through an interviewer-administered questionnaire, comparing HIV patients late and early presented to care. Logistic regression was performed to estimate odds ratio and 95% confidence intervals. Results show that 51.9% were late presenters for HIV. No differences were found in gender distribution, marital status, or access to health services between cases and controls. Participants who undertook an HIV test by doctor indication were more likely to present late compared with those who tested for HIV by their own initiative. Also, individuals taking less time to initiate ART are more likely to present late. This study highlights the need to better understand reasons for late presentation to HIV care in Cape Verde. People in older age groups should be targeted in future approaches focused on late presenters to HIV care.

  6. ASSESSING SPATIAL DATA QUALITY OF PARTICIPATORY GIS STUDIES: A CASE STUDY IN CAPE TOWN

    OpenAIRE

    K. Musungu

    2015-01-01

    Participatory GIS (PGIS) has been prescribed by scholars who sought to find a means to enable more equitable access to GIS data, diversifying the types of knowledge captured by a GIS and re-engineering GIS software. The popularity of PGIS is evident in the various studies and contexts in which it has been utilised. These include studies in risk assessment, land administration, resource management, crime mapping and urban design to mention but a few. Despite the popularity of PGIS as a body of...

  7. The Development Needs of Newly Appointed Senior School Leaders in the Western Cape South Africa: A Case Study

    Directory of Open Access Journals (Sweden)

    Nelius Jansen van Vuuren

    2017-12-01

    Full Text Available The essential role that senior school leaders play in school leadership teams to ensure effective strategic leadership in schools has been the subject of intense discussion for many years. Crucial to this debate is the establishment of professional learning and leadership approaches for newly appointed senior school leaders. Recommendations for policy and practice highlight the importance of appropriate, multifaceted, developmental support initiatives for newly appointed school leaders. In many countries, including South Africa, a teaching qualification and, in most cases, extensive teaching experience is the only requirement for being appointed as a senior school leader in a school. This tends to suggest that no further professional development is required for newly appointed school leaders, the problem addressed in this paper. This paper reports on the main findings of the perceived development needs of newly appointed senior school leaders in the Western Cape, South Africa, and suggests that school leaders occupy a unique and specialist role in education, which requires relevant and specific preparation to support effective leadership. The respondents of this study report a lack of contextualised training and support before and after their appointment in their new roles creating unique development needs. This paper, therefore, employs a mixed-method approach to gather data to understand the perceived needs of twenty newly appointed senior school leaders in the Western Cape, South Africa.

  8. Association Study Reveals Novel Genes Related to Yield and Quality of Fruit in Cape Gooseberry (Physalis peruviana L.

    Directory of Open Access Journals (Sweden)

    Francy L. García-Arias

    2018-03-01

    Full Text Available Association mapping has been proposed as an efficient approach to assist plant breeding programs to investigate the genetic basis of agronomic traits. In this study, we evaluated 18 traits related to yield, (FWP, NF, FWI, and FWII, fruit size-shape (FP, FA, MW, WMH, MH, HMW, DI, FSI, FSII, OVO, OBO, and fruit quality (FIR, CF, and SST, in a diverse collection of 100 accessions of Physalis peruviana including wild, landraces, and anther culture derived lines. We identified seven accessions with suitable traits: fruit weight per plant (FWP > 7,000 g/plant and cracked fruits (CF < 4%, to be used as parents in cape gooseberry breeding program. In addition, the accessions were also characterized using Genotyping By Sequencing (GBS. We discovered 27,982 and 36,142 informative SNP markers based on the alignment against the two cape gooseberry references transcriptomes. Besides, 30,344 SNPs were identified based on alignment to the tomato reference genome. Genetic structure analysis showed that the population could be divided into two or three sub-groups, corresponding to landraces-anther culture and wild accessions for K = 2 and wild, landraces, and anther culture plants for K = 3. Association analysis was carried out using a Mixed Linear Model (MLM and 34 SNP markers were significantly associated. These results reveal the basis of the genetic control of important agronomic traits and may facilitate marker-based breeding in P. peruviana.

  9. Association Study Reveals Novel Genes Related to Yield and Quality of Fruit in Cape Gooseberry (Physalis peruviana L.).

    Science.gov (United States)

    García-Arias, Francy L; Osorio-Guarín, Jaime A; Núñez Zarantes, Victor M

    2018-01-01

    Association mapping has been proposed as an efficient approach to assist plant breeding programs to investigate the genetic basis of agronomic traits. In this study, we evaluated 18 traits related to yield, (FWP, NF, FWI, and FWII), fruit size-shape (FP, FA, MW, WMH, MH, HMW, DI, FSI, FSII, OVO, OBO), and fruit quality (FIR, CF, and SST), in a diverse collection of 100 accessions of Physalis peruviana including wild, landraces, and anther culture derived lines. We identified seven accessions with suitable traits: fruit weight per plant (FWP) > 7,000 g/plant and cracked fruits (CF) cape gooseberry breeding program. In addition, the accessions were also characterized using Genotyping By Sequencing (GBS). We discovered 27,982 and 36,142 informative SNP markers based on the alignment against the two cape gooseberry references transcriptomes. Besides, 30,344 SNPs were identified based on alignment to the tomato reference genome. Genetic structure analysis showed that the population could be divided into two or three sub-groups, corresponding to landraces-anther culture and wild accessions for K = 2 and wild, landraces, and anther culture plants for K = 3. Association analysis was carried out using a Mixed Linear Model (MLM) and 34 SNP markers were significantly associated. These results reveal the basis of the genetic control of important agronomic traits and may facilitate marker-based breeding in P. peruviana .

  10. Falls study: Proprioception, postural stability, and slips.

    Science.gov (United States)

    Sohn, Jeehoon; Kim, Sukwon

    2015-01-01

    The present study evaluated effects of exercise training on the proprioception sensitivity, postural stability, and the likelihood of slip-induced falls. Eighteen older adults (6 in balance, 6 in weight, and 6 in control groups) participated in this study. Three groups met three times per week over the course of eight weeks. Ankle and knee proprioception sensitivities and postural stability were measured. Slip-induced events were introduced for all participants before and after training. The results indicated that, overall, strength and postural stability were improved only in the training group, although proprioception sensitivity was improved in all groups. Training for older adults resulted in decreased likelihood of slip-induced falls. The study suggested that proprioception can be improved by simply being active, however, the results suggested that training would aid older adults in reducing the likelihood of slip-induced falls.

  11. A Case Study of the Annual Evolution of the Cape Bathurst Polynya Complex in Western Amundsen Gulf, 2003-2004

    Science.gov (United States)

    Galley, R. J.; Barber, D. G.; Key, E.; Prinsenberg, S.

    2008-12-01

    A case study focused on the spatial and temporal interaction of dynamic and thermodynamic sea ice processes in the southern Beaufort Sea (SBS) and Amundsen Gulf (AG) was conducted to determine the mechanisms which form the Cape Bathurst flaw lead polynya complex over an annual cycle. This study is motivated by the need to further understand the complex interaction of the Beaufort Sea perennial sea ice pack and a seasonal sea ice zone of the SBS and AG as it is manifested in the operation of the Cape Bathurst flaw lead polynya complex. Understanding the present interplay of thermodynamic and dynamic forcing in the polynya is vital should we hope to determine how it will operate in a future Arctic dominated by seasonal sea ice. The study area has been the subject of the Canadian Arctic Shelf Exchange Study and the International Polar Year - Circumpolar Flaw Lead Study. The case study presented here further attempts to provide context in terms the physical operation of the polynya and associated flaw lead system for the biological and oceanographic measurements that were made in the course of those studies. We first describe the regional scale evolution of sea ice in western AG between fall 2003 and summer 2004 representing sea ice formation through both dynamics and thermodynamics. We investigate fine scale sea ice thickness in western AG to determine the relative contribution of leads, ridges and level sea ice in spring 2004 prior to the formation of the polynya proper. The region's potential thermodynamic sea ice growth is modeled between freeze-up in 2003 and break-up in 2004. Finally, sea ice motion in the region between freeze-up and break- up in 2004 was used to help determine the relative contribution and timing of dynamic processes on the sea ice in our case study region. It is concluded that the formation of the Cape Bathurst polynya in spring results from the interaction of the Beaufort Sea perennial pack with seasonal sea ice in AG, beginning in fall.

  12. Cape Kennedy Thunderstorms Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Cape Kennedy Thunderstorms Data contains an account of all thunderstorms reported in weather observations taken at Cape Kennedy Air Force Station, Florida between...

  13. A study on stability of rotating magnets

    International Nuclear Information System (INIS)

    Higuchi, N.; Kaiho, K.; Ishii, I.

    1996-01-01

    Superconducting power generators are being developed in Japan, as a part of a R and D program on energy technology, the New Sunshine Project. In this development, national laboratories are taking a role of fundamental studies to contribute to the R and D being carried out mainly by the manufacturers involved in a research association, Super-GM. Stabilities of magnets in a high gravitational field up to 2,000 G are discussed, based upon the experimental results of forced quench tests in a set of rotating magnets, in order to establish the stability design criterion of field windings of superconducting generators. Relations of propagation velocities, recovery currents, minimum quench energy and heat transfer characteristics are studied, a good agreement between the experimental results and a theory confirmed the improvement of magnet stability in a high gravitational field because of the enhanced heat transfer characteristics

  14. Sm-Nd study of Precambrian crustal development in the Prieska-Copperton region, Cape Province

    International Nuclear Information System (INIS)

    Cornell, D.H.; Hawkesworth, C.J.; Van Calsteren, P.; Scott, W.D.

    1986-01-01

    Samples representing the major lithological units between Copperton and Prieskapoort in the Cape Province have been analysed for Sm and Nd concentrations and Nd isotopic compositions. The ∼ 3000 Ma Marydale Group is shown to extend without major chronostratigraphic breaks from slightly metamorphosed basalt and arkose west of the Doornberg Fault at Prieskapoort to highly metamorphosed gneisses east of the Brakbos Fault at Copperton. Evidence is found of plutonic alkaline igneous activity, and possibly volcanism, which occurred during the ∼ 1 900 Ma Kheis tectogenesis. Early Proterozoic material apparently dominates the lower crustal region of the eastern Namaqua Province sampled by kimberlites. Sm-Nd data for the Copperton Formation of the Namaqua Province places an upper limit of ∼ 1 514 Ma and lower limit of ∼ 1 350 Ma on its origin. Omission of basaltic samples from the isochron regression yields the younger age, which is more easily reconciled with Pb isotope data. Volcanism is envisaged from a mantle source with a history of light rare-earth depletion relative to the chondritic earth model. By analogy with modern tectonic environments, the Copperton Formation probably formed in an active continental margin or island arc environment

  15. Remote sensing and GIS based study of potential erosion and degradation areas on the island Fogo (Cape Verde Islands)

    Science.gov (United States)

    Olehowski, Claas; Naumann, Simone; Siegmund, Alexander

    2009-09-01

    The Island of Fogo (Cape Verde) is affected by processes of erosion and degradation, caused mainly by a high population growth and global change. With its small scaled climatic, floristic and geo-ecological differentiation, the island of Fogo is an optimal research space for understanding semiarid island ecosystems in the marginal tropics and their behaviour to erosion and degradation processes. For that reason, a change detection analysis over the past two decades is generated, showing the level and direction of land cover and land use change. Two satellite images from 1984 and 2007 will classified by a Maximum Likelihood approach. In a further step, an image of 1974 will be also integrated in this change detection analysis, enlarging the study over the last three decades.

  16. The food and meal pattern in the urban African population of the Cape Peninsula, South Africa: the BRISK Study.

    Science.gov (United States)

    Bourne, L T; Langenhoven, M L; Steyn, K; Jooste, P L; Nesamvuni, A E; Laubscher, J A

    1994-06-01

    A cross sectional dietary study, utilising the 24 hour recall method, was conducted among 983 African adults aged 15 to 64 years resident in the Cape Peninsula during 1990. An evaluation of the dietary intake pattern revealed a diet confined to a relatively narrow range of foods, but little evidence of nutrient-empty food intake. In terms of recommendations, insufficient dairy products and vegetables and fruits were consumed, while requirements for intakes of cereals and components of the meat and fat groups were met. Supper emerged as the main meal of the day, contributing most of the energy and was consumed by 89 pc of respondents. Between meal eating made a valuable contribution to total nutrient intake. The low intakes of dairy products and vegetables and fruits and the apparent move away from the traditional diet present particularly great challenges.

  17. Self-reported chemicals exposure, beliefs about disease causation, and risk of breast cancer in the Cape Cod Breast Cancer and Environment Study: a case-control study

    OpenAIRE

    Zota, Ami R; Aschengrau, Ann; Rudel, Ruthann A; Brody, Julia

    2010-01-01

    Abstract Background Household cleaning and pesticide products may contribute to breast cancer because many contain endocrine disrupting chemicals or mammary gland carcinogens. This population-based case-control study investigated whether use of household cleaners and pesticides increases breast cancer risk. Methods Participants were 787 Cape Cod, Massachusetts, women diagnosed with breast cancer between 1988 and 1995 and 721 controls. Telephone interviews asked about product use, beliefs abou...

  18. Decommissioning and decontamination (burial ground stabilization) studies

    International Nuclear Information System (INIS)

    Cline, J.F.

    1980-01-01

    The decommissioning and decontamination of retired Hanford facilities and the future use of surrounding landscapes require isolation of contaminated wastes from the biosphere. Burial ground stabilization studies were conducted to determine the effectiveness of physical barriers for isolating contaminated wastes in shallow-land burial sites from plants and animals. This study was undertaken to determine the effectiveness of using a layer of loose rock between the waste and the surface soil covering to prevent both plant root and animal penetrations

  19. Preliminary Slope Stability Study Using Slope/ W

    International Nuclear Information System (INIS)

    Nazran Harun; Mohd Abd Wahab Yusof; Kamarudin Samuding; Mohd Muzamil Mohd Hashim; Nurul Fairuz Diyana Bahrudin

    2014-01-01

    Analyzing the stability of earth structures is the oldest type of numerical analysis in geotechnical engineering. Limit equilibrium types of analyses for assessing the stability of earth slopes have been in use in geotechnical engineering for many decades. Modern limit equilibrium software is making it possible to handle ever-increasing complexity within an analysis. It is being considered as the potential method in dealing with complex stratigraphy, highly irregular pore-water pressure conditions, various linear and nonlinear shear strength models and almost any kind of slip surface shape. It allows rapid decision making by providing an early indication of the potential suitability of sites based on slope stability analysis. Hence, a preliminary slope stability study has been developed to improve the capacity of Malaysian Nuclear Agency (Nuclear Malaysia) in assessing potential sites for Borehole Disposal for Disused Sealed Radioactive Sources. The results showed that geometry of cross section A-A ' , B-B ' , C-C ' and D-D ' achieved the factor of safety not less than 1.4 and these are deemed acceptable. (author)

  20. Study of TATP: stability of TATP solutions.

    Science.gov (United States)

    Pachman, Jiri; Matyáš, Robert

    2011-04-15

    Stability of raw TATP (3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexoxonane) samples in solutions of common solvents was studied to highlight problems faced by forensic labs in identification and analysis of organic peroxide samples. The TATP samples were prepared by reaction of acetone and hydrogen peroxide (30%) with the aid of following catalysts: hydrochloric, sulfuric, nitric, perchloric and methanesulfonic acid. Acetone, acetonitrile, methanol and acetonitrile/water solutions of TATP samples were prepared and stored at 50°C. Various degrees of stability were observed for particular combination of catalyst and solvent ranging from totally unstable (catalyst-H(2)SO(4)/any solvent) to very stable (catalyst-HCl/solvent acetonitrile). Purification of crude TATP by re-crystallization results in product stable in all investigated solvents. Stability of solution prepared from re-crystallized DADP (3,3,6,6-tetramethyl-1,2,4,5-tetroxane) was found to be on the same level as the stability of solution of re-crystallized TATP. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  1. The impact of Information Systems usage on productivity: A retrospective analysis and an empirical study in Cape Town tourism of South Africa

    Directory of Open Access Journals (Sweden)

    Anthony Bere

    2014-01-01

    Full Text Available In this article, the researchers examine the direct impact of Information Systems Usage to Productivity at Cape Town Tourism. Data for the full sample of individuals who use information systems was analysed. The results clearly demonstrate that information systems has a positive impact on productivity. This is compromised however when there is a lack of training and poor systems performance. The study determined that in order to obtain the best out of the system, end users need to be consulted before implementation of any new system. System performance was also found out to be problematic as faced by employees of Cape Town Tourism when using their information systems.

  2. Small Ro/Pax Vessel stability study

    DEFF Research Database (Denmark)

    Erichsen, Henrik; Kristensen, Hans Otto Holmegaard; Jensen, Jørgen Juncher

    2015-01-01

    not sufficient, i.e. that the current safety level according to SOLAS 2009 is less than the old safety level according to SOLAS 90. In order to establish a solid foundation for the discussion, this study was made possible by a grant from The Danish Maritime Fund. The study focus on small ro/pax vessels......In 2009 new damage stability requirements for passenger ships based on a probabilistic method were adopted by IMO and are now part of the current SOLAS Chapter II-1 regulations (SOLAS 2009). The mandate from IMO was to keep the same safety level as inherent in the old deterministic damage stability...... regulations in SOLAS (SOLAS 90). During the rule development prior to the adoption, it was argued that the safety level for large passenger ships should be increased, but small ro/pax vessels were only rudimentarily looked at and small vessels with very high attained index were seen as “non...

  3. Questioning the Pace and Pathway of E-Government Development in Africa: A Case Study of South Africa's Cape Gateway Project

    Science.gov (United States)

    Maumbe, Blessing Mukabeta; Owei, Vesper; Alexander, Helen

    2008-01-01

    The paper examines e-government development in Africa. This study is based on the Cape Gateway project in South Africa, a leading e-government initiative on the continent. We observe that African countries have jumped on the e-government band wagon by looking mostly at the benefits without a clear risk assessment. We argue that African countries…

  4. The use of earth observation data in hydrological investigations – a case study in a Semi-Arid Catchment (Western Cape, South Africa)

    CSIR Research Space (South Africa)

    Bugan, Richard DH

    2014-01-01

    Full Text Available data in hydrological investigations – a case study in a Semi-Arid Catchment (Western Cape, South Africa) Bugan, Richard DH Jovanovic, Nebojsa Garcia, C Teich, I ABSTRACT: The availability of hydrological data is a critical component in water...

  5. Agricultural chemical exposures and birth defects in the Eastern Cape Province, South Africa A case – control study

    Directory of Open Access Journals (Sweden)

    Tyler Joanne

    2003-10-01

    Full Text Available Abstract Background South Africa is one of the major users of pesticides on the African continent. The Eastern Cape is the second largest province in South Africa. There has been growing concern about the occurrence of certain birth defects which seemed to have increased in the past few years. In this paper we investigate associations between exposure to agricultural chemicals and certain birth defects. Few such studies have been undertaken in the developing world previously. Methods Between September 2000 and March 2001 a case – control study was conducted among rural women in the area of the Eastern cape to investigate the association between women's exposure to pesticides and the occurrence of birth defects. Information on birth defects was obtained from the register of the Paediatrics Department at the Cecilia Makiwane Hospital in Mdantsane, one of the largest referral hospitals in the province. The cases were children who were diagnosed with selected birth defects. The controls were children born in the same areas as the cases. Exposure information on the mothers was obtained by interview concerning from their activities in gardens and fields. Data were analysed using conditional logistic regression. Results A total of 89 case mothers and 178 control mothers was interviewed. Babies with birth defects were seven times more likely to be born to women exposed to chemicals used in gardens and fields compared to no reported exposure (Odds Ratio 7.18, 95% CI 3.99, 13.25; and were almost twice as likely to be born to women who were involved in dipping livestock used to prevent ticks (OR 1.92, 95% CI 1.15, 3.14. They were also 6.5 times more likely to be born to women who were using plastic containers for fetching water (OR 6.5, 95% CI 2.2, 27.9. Some of these containers had previously contained pesticides (OR 1.87, 95% CI 1.06, 3.31. Conclusions These findings suggest a link between exposure to pesticides and certain birth defects among the

  6. Avisalmvac: evaluation studies of stability and toxicity

    Directory of Open Access Journals (Sweden)

    Daniela Botus,

    2008-12-01

    Full Text Available In Pasteur Institute laboratories there was developed AVISALMVAC, a vaccine against avian Salmonella, a biological product that contains S. enteritidis and S. typhimurium bacterin, with oil adjuvant. This paper presents the results of the studies regarding the stability and toxicity evaluation of this vaccine stored under conditions recommended by the manufacturer (2-80C at the end of the period of validity. The vaccine stability was assessed by serological and histopathological analysis of samples from SPF chickens vaccinated with the product at the end of the period of validity. The study of Avisalmvac toxicity was carried out by inoculation of the product or its components on Vero cell monolayer, and the effects were microscopically recorded or by MTT test, applied at 6 days post-inoculation. Antibody titers recorded at 2 and 3 weeks post vaccination demonstrated the vaccine ability (used after an year since manufacture to induce synthesis of specific antibodies and therefore, the product stability was proven. Histopathological examinations carried out on samples taken at 18 days post vaccinationfrom the vaccination site (skeletal muscle and skin and spleen, did not show any lesions associated to vaccination with Avisalmvac. The cytotoxicity analysis made by inoculating the vaccine or its components on Vero cell monolayer and the microscopic examination did not record visible cytopathic effects for any vaccine dilutions or vaccine components. The cell metabolism evaluation by MTT assay made at 6 days after vaccine/vaccine components inoculation on Vero monolayer, shown the ability of the vaccine and oil adjuvant to stimulate cell metabolism, and a certain degree of toxicity / inhibition of dehydrogenase metabolism associated to one of emulsifier but at dilutions higher than those used in the vaccine formula.

  7. The role of the state in stock farming in rural areas: A case study of Hertzog, Eastern Cape, South Africa.

    Science.gov (United States)

    Jenjezwa, Vimbai R; Seethal, Cecil E P

    2014-08-19

    This study examined the role of the state in providing veterinary services to resource-poor stock farmers. Communal stock farmers in most rural areas have low incomes and generally poor access to commercial veterinary healthcare. The state veterinary services thus offer a means for stock farmers to maintain the health of their livestock and receive information on animal healthcare. Interviews and participant observation were used to collect data about animal healthcare practices in Hertzog, a village in the Eastern Cape Province of South Africa.The findings were that the state played an important role in animal healthcare and in the education of farmers. However, the lack of a skilled workforce was a constraint to effective service delivery, whilst veterinary educational institutions that disseminate information to the stock farmers were not utilised. It is thus important to fully utilise training centres to educate stock farmers and for more incentives to be given to state employees, so as to attract the necessary skilled personnel to improve service delivery.

  8. Demographic and circumstantial accounts of burn mortality in Cape Town, South Africa, 2001-2004: An observational register based study

    Directory of Open Access Journals (Sweden)

    Laflamme L

    2009-10-01

    Full Text Available Abstract Background Burns are a persisting public health problem in low- and middle-income countries; however, epidemiologic data for these settings is scarce. South Africa is no exception although there is an emerging knowledge base, especially for paediatric burns. The current study describes the epidemiology of burn mortality across the lifespan in Cape Town (2.9 million inhabitants in 2001, one of the six South African metropolitan centres. Methods The distribution of burn mortality across socio-demographic groups and also their circumstances of occurrence were investigated using four year (2001 to 2004 surveillance data from the National Injury Mortality Surveillance System (n = 1024 cases. Results Burn mortality occurred at a rate of 7.9 per 100 000 person-years (95% CI: 7.3-8.3. Males sustained fatal rates 2.2 times more than that for females (p Conclusion Besides paediatric burns, the high prevalence and circumstances of occurrence of burns among middle age men are a source of concern. There are reasons to believe that this over-representation is a reflection of detrimental living conditions, life-style and poor socio-economic status. It is recommended that there be greater prioritisation of prevention activities that involve the control or management of kerosene heat sources, the provision of alternatives to flammable housing materials, and the implementation of strategies to reduce harmful drinking practices.

  9. A prospective study of methamphetamine use as a predictor of high school non-attendance in Cape Town, South Africa

    Directory of Open Access Journals (Sweden)

    Parry Charles D

    2010-10-01

    Full Text Available Abstract Background This prospective study investigated the association between life-long methamphetamine and other drug use and high school non-attendance, in a sample of high school students in Cape Town, South Africa. Methods A random sample of 1535 high school students completed a baseline questionnaire in 2006, and were asked to complete a follow-up questionnaire 12 months later. The questionnaire included questions on substance use, including tobacco, alcohol, methamphetamine and cannabis use, demographic factors, and questions relating to school attendance and performance. Results Forty-three percent of the students surveyed at baseline did not complete a follow-up questionnaire after 12 months. Compared with students who were not using selected substances, an adjusted logistic regression model showed that life-time methamphetamine use in addition to other substances was significantly associated with non-attendance (OR = 2.58, 95% CI: 1.24 - 5.36 when other non-substance use factors (repeating a year at school and being older than the norm for current grade were taken into account. Conclusions Early identification of students with methamphetamine and other substance use problems, and a supportive rather than punitive school policy, may be valuable in improving high school completion and student retention rates.

  10. Developing and Institutionalising Supply Chain Management Procedures: A Case Study of the Eastern Cape Dept of Roads and Public Works

    Directory of Open Access Journals (Sweden)

    Vukile Dlova

    2014-03-01

    Full Text Available This article presents findings from a case study research in the Eastern Cape Department of Roads and Public Works. It systematically investigates why public institutions fail to implement their Supply Change Management (SCM policies and procedures. The article provides a clear context for the researchand explains why policies and procedures are vital for organisations. It also illustrateshow policies and procedures are a meansto effective supply chain systems and describes the research method, population and sample. Findings based on the set outcriteria for good institutionalisation of policies and procedures showed that although SCM policies and procedures areprovided to employees and they were aware of the existence of theseinstruments, there was very little participation of employees in the development and review of these policies.  Based on the findings of the research, a key recommendation is that practitioners, are involved in the day to day implementation of the SCM process in public institutions, should also be involved in the development processes of SCM policies and procedures. The research also argues that for public institutions to be effective and efficient, clear departmental guidelines should be simple and straight forward language should be used so as to avoid different interpretations by implementers. These two critical points will contribute to the effective and efficient development and institutionalization of SCM policies and procedures in government institutions.

  11. A prospective study of the demographics, management and outcome of patients with acute kidney injury in Cape Town, South Africa.

    Directory of Open Access Journals (Sweden)

    Thandiwe A L Dlamini

    Full Text Available To study the demographics and outcome of acute kidney injury (AKI at Groote Schuur Hospital, Cape Town, South Africa.A prospective observational study of AKI fulfilling the Kidney Disease: Improving Global Outcomes definition, from 8 July 2012 to 8 July 2013. Ethics approval was granted by the University of Cape Town Human Research Ethics Committee. Consent was waived because patient data was de-identified and patient management was not adversely affected by the study. A clerking sheet was used for data collection. Patients were reassessed after 3 months. Main outcomes were renal recovery and 3 month mortality. Descriptive statistics and multivariate logistic regression were carried out for risk factors. Over this period there were 10,750 hospital admissions and 366 patients with AKI giving an incidence of 3.4%. Median age was 44 years (IQR 14-82 and 214 (58.5% were male, with 152 (41.5% female. Most, 265 (72.4%, had community acquired AKI. Common underlying comorbidities were hypertension (n = 152, 41.5%, diabetes mellitus (n = 65, 17.8% Human immunodeficiency virus (HIV (n = 75, 20.6%, heart disease (n = 58, 16.1%, and chronic kidney disease (n = 37, 10.1%. Renal biopsies were performed in 36 (9.8% patients. In total, 202 (55.2% patients were in the intensive care unit, and of the whole study population 204 (55.7% were dialysed. Those admitted to ICU who required dialysis amounted to 145 (39.6%. The overall 3 month mortality was 38.8%. Among the 145 patients dialysed in ICU, there were 71 deaths (49% at 3 month follow up. Of the 119 patients with follow up serum creatinine, 95 (79.8% had full renal recovery, and 4 (3.4% had end-stage renal disease. On multivariate analysis, mechanical ventilation was associated with 3 month mortality (OR 2.46, p-value 0.019, 95% CI 1.41-4.03. Sepsis had a borderline significant association (OR 1.83, P-value 0.066, 95%CI 1.02-3.27, as did prolonged time to dialysis (OR 1.93, p-value 0.08, 095% CI 0.93-4.03. HIV

  12. Study of theophylline stability on polymer matrix

    International Nuclear Information System (INIS)

    Rodrigues, Kiriaki M.S.; Parra, Duclerc F.; Oliveira, Maria Jose A.; Bustillos, Oscar V.; Lugao, Ademar B.

    2007-01-01

    Theophylline is a bronchodilator, commonly known and used as a drug model in the development of pharmaceutical formulations. The stability of the drug and the matrix, scope of this study, was evaluated in the solid formulation. Polymeric matrix based on PHB containing the drug (theophylline) was prepared and submitted to radiation sterilization at different doses of: 5, 10, 20 and 25 kGy using a Cobalt- 60 source. The modified drug release of theophylline sterilized tablets has been studied. Modern techniques of HPLC (High Pressure Liquid Chromatography), DSC (Differential scanning calorimetry) and TGA (Thermogravimetry analysis) were employed. The results have shown the influence of sterilization by radiation process in both the theophylline and the polymeric drug delivery matrix samples. The increasing of polymeric matrix crosslinking under radiation conditions retards the drug release while the theophylline structure is stable under the radiation (author)

  13. Study on stability of DMS meridian detector.

    Science.gov (United States)

    Yang, Ning; Huang, Li; Yuan, Jiamin; Zhang, Zhifang; Yang, Zhimin

    2016-05-01

    The stability of meridian detector was the basis to study meridian through conductance method. Ancient documents mentioned that the human body's blood could change with the time and meridians. When qi and blood came, the qi and blood would be full of that place; when qi and blood gone, the local skin shining could fade and recess. It liked the tidal fluctuation, then caused the corresponding acupuncture points conductance value changes. Modern studies had reported that meridian detector instrument the skin area of twelve meridians acupuncture points could change along with time within 24 hours. In this circumstance, whether the conductance values changes in human acupuncture points had statistical significance was vital important. DMS meridian detector instruction was adopt to measure the twelve meridian jingyuan acupuncture point in order to analyze the acupuncture point conductance value changes within one day.

  14. Fire management in Mediterranean-climate shrublands: a case study from the Cape fynbos, South Africa

    CSIR Research Space (South Africa)

    van Wilgen, BW

    2010-01-01

    Full Text Available The authors used a spatial data base of fires within 10 protected areas covering >720 000 ha to examine the frequency, seasonality, size and cause of fires over four decades. Their study covered five fire climate zones and a range of mountain fynbos...

  15. Private sector community forestry partnerships in the Eastern Cape – The Manubi woodlot case study

    CSIR Research Space (South Africa)

    Cocks, M

    2000-01-01

    Full Text Available been made possible by the financial support of the UK Department for International Development and the European Commission iii Citation: Cocks, M., Matsiliza, B & Fabricius, C. 2000. Private-Sector Community Forestry Partnerships in the Eastern... contracting in South Africa. This study of trends in outsourcing and contracting in the South African forest industry seeks to deepen understanding of the national context within which contracting is an increasing practice, and examines possible options...

  16. Mapping the N-Year design rainfall - A case study for the Western Cape

    CSIR Research Space (South Africa)

    Khuluse, S

    2010-11-01

    Full Text Available distribution (GPD) approximation to exceedances is plausible. This includes examining the sensitivity of the average excess, the dispersion index and return level values to a range of threshold values. Inference for the extreme value model is done by maximum... continuous surface over the study area. This continuous surface or spatial random field is denoted as fY (s; t) : s 2 D R2; t 2 Tg, whereD is a fixed, continuous subset of a two-dimensional plane and t 2 T is an index for the temporal component...

  17. Stability studies on piroxicam encapsulated niosomes.

    Science.gov (United States)

    Ertekin, Zehra Ceren; Bayindir, Zerrin Sezgin; Yuksel, Nilufer

    2015-01-01

    Drug delivery systems which yield ideal treatments are currently the center of interest for researchers. Niosomes have numerous advantages over other drug delivery systems. However, stability issue is not clear yet and is a serious drawback for niosomes. In this study, the stability of niosomes was the center of interest. Piroxicam which was chosen as the model drug was loaded to niosomes. Niosomes were prepared by thin-film method and different forms (aqueous dispersion, lyophilized powder and lyophilized powder with cryoprotectant) of the original niosome formulation were prepared. The samples were stored either at 5°C±3°C or 25°C±2°C/60% RH±5% RH for 3 months. The drug leakage percent, particle size and distribution, zeta potential, drug release profiles were determined and niosomes were visualized under optic microscope. Niosome formulation provided sustained release of piroxicam. The drug leakage from stored niosomes was observed at the level of 1.56-6.63 %. Individual vesicle images were obtained for all samples by optical microscope. However, particle size of niosomes was increased upon storage. The zeta potential values were neither related to time nor physical form. Drug release profiles and amounts were quite similar for all forms of niosomes and the original formulation but a slight decrease was noticed on drug release amounts by time. This indicates that niosomes become more rigid by time. Although the ideal storage was obtained with lyophilized niosomes at 5±3°C in this study, the usage of suitable cryoprotectant and optimized lyophilization process should be further evaluated.

  18. An environmental isotope study of a major dewatering operation at Sishen mine, northern Cape Province

    International Nuclear Information System (INIS)

    Verhagen, B.T.; Smith, P.E.; Dziembowski, Z.; Oosthuizen, J.H.

    1978-01-01

    Geohydrological studies using environmental isotopes of the Sishen iron ore mine were started after major rainfalls in 1973/74 produced flooding of the open cast workings. The mine is underlain by dolomite which has been extensively karstified and geohydrologically compartmentalized by several dykes. Major dewatering takes place in a pit called Hill 2 by pumping an array of large diameter boreholes at a combined rate of 2000 m 3 h -1 . The probable recharge areas (dolomites, superficial Kalahari Beds) were isotopically surveyed to assess their relative importance to the dewatering problem. Several major pumping outlets at the mine were regularly sampled for isotopic and chemical analysis and from the data a preliminary mixing model is proposed. The data also show that with the total pumped volume up to March 1978, no very recent (i.e. post bomb) water has reached the dewatering points. On this basis a minimum storage of 0.75 x 10 8 m 3 is derived compared to a classical calculation of 10 8 m 3 for the compartment. Isotopic composition and response differ for waters on either side of a dyke crossing the mining area, corroborating classical evidence suggesting that the dyke acts as an aquiclude. (orig.) [de

  19. Language policy and speech practice in Cape Town: An exploratory ...

    African Journals Online (AJOL)

    Language policy and speech practice in Cape Town: An exploratory public health sector study. Michellene Williams, Simon Bekker. Abstract. Public language policy in South Africa recognises 11 official spoken languages. In Cape Town, and in the Western Cape, three of these eleven languages have been selected for ...

  20. Sustainable solutions for cooling systems in residential buildings: case study in the Western Cape Province, South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Foudzai, F.; M' Rithaa, M. [Cape Peninsula University of Technology, Cape Town (South Africa). Dept. of Industrial Design

    2010-07-01

    The energy demand in building sectors for summer air-conditioning is growing exponentially due to thermal loads, increased living standards and occupant comfort demands throughout the last decades. This increasing consumption of primary energy is contributing significantly to emission of greenhouse gases and therefore to global warming. Moreover, fossil fuels, current main sources of energy used for electricity generation, are being depleted at an alarming rate despite continued warning. In addition, most air-conditioning equipment still utilise CFCs, promoting further destruction of our planet's protective ozone layer. Concerns over these environmental changes, have begun shifting the emphasis from current cooling methods, to 'sustainable strategies' of achieving equally comfortable conditions in building interiors. Study of ancient strategies applied by vernacular architecture shows how the indigenously clean energies to satisfy the cooling need were used. One of the most important influences on vernacular architecture is the macro-climate of the area in which the building is constructed. Mediterranean vernacular architecture, as well as that of much of the Middle East, often includes a courtyard with a fountain or pond; air cooled by water mist and evaporation is drawn through the building by the natural ventilation set up by the building form, and in many cases also includes wind-catchers to draw air through the internal spaces. Similarly, Northern African vernacular designs often have very high thermal mass and small windows to keep the occupants cool. Not only vernacular structure but also the recent development in solar and geothermal cooling technologies could be used to the needs for environmental control. Intelligent coupling of these methods as alternative design strategies could help developing countries such as South Africa toward sustainable development in airconditioning of building. In this paper, the possible strategies for

  1. Cape Kennedy Tower Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitized data taken from original weather observations taken at Cape Kennedy Air Force Station, Florida. Elements recorded are wind speed and direction, wind speed...

  2. Cape Kennedy Weather Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitized data taken from original weather observations taken at Cape Kennedy Air Force Station, Florida. Elements recorded are wind speed and direction,...

  3. Self-induction of abortion among women accessing second-trimester abortion services in the public sector, Western Cape Province, South Africa: an exploratory study.

    Science.gov (United States)

    Constant, D; Grossman, D; Lince, N; Harries, J

    2014-04-01

    Despite South Africa's liberal abortion law permitting abortion on request in the first trimester and under restricted conditions for second-trimester pregnancies, the practice of unsafe self-induced abortion persists. However, the prevalence of this practice, the methods used and the reasons behind it are relatively under-researched. As part of a larger study seeking to improve abortion services in the Western Cape Province, we explored reports of prior attempts to self-induce abortion among women undergoing legal second-trimester abortion. To describe the prevalence and methods of and factors related to unsuccessful attempts at self-induction of abortion by women presenting without complications and seeking second-trimester abortion at public health facilities in the Western Cape. In a cross-sectional study from April to August 2010, 194 consenting women undergoing second-trimester abortion were interviewed by trained fieldworkers using structured questionnaires at four public sector facilities near Cape Town. Thirty-four women (17.5%; 95% confidence interval 12.7 - 23.4) reported an unsuccessful attempt to self-induce abortion during the current pregnancy before going to a facility for second-trimester abortion. No factors were significantly associated with self-induction, but a relatively high proportion of this small sample were unemployed and spoke an indigenous African language at home. A readily available herbal product called Stametta was most commonly used; other methods included taking tablets bought from unlicensed providers and using other herbal remedies. No use of physical methods was reported. The prevalence of unsafe self-induction of abortion is relatively high in the Western Cape. Efforts to inform women in the community about the availability of free services in the public sector and to educate them about the dangers of self-induction and unsafe providers should be strengthened to help address this public health issue.

  4. Lipid Profile and High Maternal Body Mass Index is Associated with Preeclampsia: A Case-Control Study of the Cape Coast Metropolis.

    Science.gov (United States)

    Ephraim, Rkd; Doe, Pa; Amoah, S; Antoh, Eo

    2014-09-01

    Preeclampsia is a leading cause of maternal mortality worldwide and a serious health problem that affects the majority of women. We investigated the association between lipid profile and maternal obesity among preeclamptic women in the Cape Coast Metropolis. This case-control study involved 60 preeclamptics and 50 healthy pregnant controls matched for age and gestational weeks consecutively recruited from two major hospitals in the Cape Coast Metropolis. Blood samples were collected after overnight fasting and enzymatic spectrophotometric tests used to estimate lipid concentrations. The independent samples t-test, Chi-square, and Pearson's correlation were used in the analysis of data gathered. Serum triglyceride (TG) (P = 0.04), very low density lipoprotein (VLDL) (P = 0.02), TC (P = 0.01) and low density lipoprotein (LDL) (P = 0.03) levels were higher in preeclamptic participants than in the controls. High density lipoprotein concentration showed no significant variation between the two groups (P = 0.83). Preeclamptic women were more obese (P = 0.07). High body mass index (OR = 1.501; CI = 0.926-2.106, P = 0.01), high TG level (OR = 5.026; CI = 0.794-31.818, P = 0.01), were associated with preeclampsia. Lipid abnormalities, mostly elevated levels of TG, TC, LDL, and VLDL are present in preeclamptics. High TG levels and maternal obesity are associated with preeclampsia among pregnant women in the Cape Coast Metropolis.

  5. Age-disparity, sexual connectedness and HIV infection in disadvantaged communities around Cape Town, South Africa: a study protocol

    Directory of Open Access Journals (Sweden)

    Aerts Marc

    2011-08-01

    Full Text Available Abstract Background Crucial connections between sexual network structure and the distribution of HIV remain inadequately understood, especially in regard to the role of concurrency and age disparity in relationships, and how these network characteristics correlate with each other and other risk factors. Social desirability bias and inaccurate recall are obstacles to obtaining valid, detailed information about sexual behaviour and relationship histories. Therefore, this study aims to use novel research methods in order to determine whether HIV status is associated with age-disparity and sexual connectedness as well as establish the primary behavioural and socio-demographic predictors of the egocentric and community sexual network structures. Method/Design We will conduct a cross-sectional survey that uses a questionnaire exploring one-year sexual histories, with a focus on timing and age disparity of relationships, as well as other risk factors such as unprotected intercourse and the use of alcohol and recreational drugs. The questionnaire will be administered in a safe and confidential mobile interview space, using audio computer-assisted self-interview (ACASI technology on touch screen computers. The ACASI features a choice of languages and visual feedback of temporal information. The survey will be administered in three peri-urban disadvantaged communities in the greater Cape Town area with a high burden of HIV. The study communities participated in a previous TB/HIV study, from which HIV test results will be anonymously linked to the survey dataset. Statistical analyses of the data will include descriptive statistics, linear mixed-effects models for the inter- and intra-subject variability in the age difference between sexual partners, survival analysis for correlated event times to model concurrency patterns, and logistic regression for association of HIV status with age disparity and sexual connectedness. Discussion This study design is

  6. An Africanised Study of Astronomical History in the Northern Cape South Africa, for Purposes of Secondary and Higher Education Programmes

    Science.gov (United States)

    de Beer, K. J.; Hoffman, M. J.

    2007-07-01

    Dr M.J. Hoffman, Head of the Department Physics, University of the Free State (UFS), presented a paper at the Duineveld Secondary School in Upington, to enhance the idea of a natural observatory centre in the Northern Cape. Quite aptly, the National Institute for Higher Education: Northern Cape (NIHE) also invited a renowned African astronomer, Dr T Medupe, to address their graduation ceremony in 2005. However, Dr Albert Strydom, Programme Head of Tourism Management at the Central University for Technology, Free State (CUT), is very much aware of the delicate nature of this type of high scientific profile in Tourism Management. It is foreseen by Dr Kallie de Beer, Director of Distance Education, that teaching and learning in this field will predominantly be conducted via Open and Distance e-Learning (ODeL). Consequently, it is also important to understand the philosophy of ODeL within global and Africanized perspectives. Astronomy, in this case, offers excellent examples of Africanised science in practice to add scientific value to tourist packages in the Northern Cape. (www.saao.ac.za/assa/aahs).

  7. Explorations in Aeolian Ecology: Radar and Visual Studies of the Aerofauna during the Convection and Precipitation/electrification (cape) Experiment.

    Science.gov (United States)

    Russell, Robert William

    I studied the ecology of aerial insects and birds (the "aerofauna") during the Convection and Precipitation/Electrification (CaPE) Experiment in Florida during the summer of 1991. Visual observations were coordinated with simultaneous measurements of atmospheric motions, permitting novel explorations of: (1) patterns and processes in the distribution of "aerial plankton" (i.e., small, weakly flying insects that drift with boundary-layer winds); (2) the feeding ecology of "aerial planktivores" (i.e., predators that feed on aerial plankton); and (3) the flight tactics of soaring birds. Sensitive Doppler radars regularly detected fine lines of enhanced reflectivity in boundary-layer convergence zones. These "fine lines" were attributable to dense concentrations of aerial plankton entrained by the convergent airflow. Insect densities were inferred to be about an order of magnitude higher inside convergence zones then elsewhere. Anecdotal observations suggested that large quantities of aerial plankton entrained in convergence zones were sometimes "scrubbed" from the boundary layer by precipitation. Radar images clearly depicted the rapid aeolian transport of aerial plankton across the landscape, but also showed that densities of aerial plankton became concentrated along coastlines when winds blew toward the sea. In contrast, airspace over the adjacent ocean remained largely free of radar echoes under all wind conditions. The coastal concentrations, together with the absence of overwater echoes, indicate that the organisms comprising the aerial plankton respond behaviorally to coastlines to avoid being blown out to sea. Several species of aerial insectivorous predators commonly exploited boundary-layer fine lines as food resources. Chimney swifts (Chaetura pelagica), barn swallows (Hirundo rustica), and wandering gliders (Pantala flavescens) showed significant responses to fine lines. Details of these responses differed, but this variation clearly reflected species

  8. Aerosol size-resolved trace metal composition in remote northern tropical Atlantic marine environment: case study Cape Verde islands

    Science.gov (United States)

    Fomba, K. W.; Müller, K.; van Pinxteren, D.; Herrmann, H.

    2013-05-01

    Size-resolved trace metal concentrations of 15 elements in aerosol particles at the Cape Verde Atmospheric Observatory (CVAO) under remote background conditions were investigated through analysis of aerosol samples collected during intensive field studies from January 2007 to November 2011 using total reflection x-ray fluorescence (TXRF). The identification of the main air mass origin that influence remote marine aerosol in the northern tropical Atlantic has been investigated. In total, 317 samples were collected. The dataset was analyzed according to the main air mass inflow at the station. We found that remote conditions make up about 45% of the meteorological conditions in a year at CVAO and thus the northern tropical Atlantic. Surprisingly, air masses from North America are often responsible for higher trace metal concentrations in this region. Elements such as Zn, Pb, Cu, Cr, Ni, and V were mostly found in the submicron size fractions, while elements with dominant crustal or oceanic origin such as Fe, Ti, Mn, Sr, and Rb were found in the coarse fractions (>1 μm). The highest metal concentrations, especially for Zn (3.23 ng m-3), Cu (0.81 ng m-3), Sr (2.63 ng m-3), and Cr (0.53 ng m-3), were observed in air masses originating from North America and the concentrations were within the same concentration range to those reported previously in the literature for remote marine aerosols. Fe (12.26 ng m-3), Ti (0.91 ng m-3), and Mn (0.35 ng m-3) showed higher concentrations when air mass came from Europe and the Canary Islands. Pb concentration was low (20) for Zn, Cu, Ni, Cr, Pb, and Se. The observed enrichment of the elements was attributed to crustal, marine, anthropogenic, and biogenic sources, as well as long-range transport and resuspension. Zn, Cu and Pb were indicators of anthropogenic activities, while Ti and Sr were indicators of crustal and marine origin, respectively. Oceanic and biogenic emissions might have contributed to most of the Se observed. This

  9. Aerosol size-resolved trace metal composition in remote northern tropical Atlantic marine environment: case study Cape Verde islands

    Directory of Open Access Journals (Sweden)

    K. W. Fomba

    2013-05-01

    Full Text Available Size-resolved trace metal concentrations of 15 elements in aerosol particles at the Cape Verde Atmospheric Observatory (CVAO under remote background conditions were investigated through analysis of aerosol samples collected during intensive field studies from January 2007 to November 2011 using total reflection x-ray fluorescence (TXRF. The identification of the main air mass origin that influence remote marine aerosol in the northern tropical Atlantic has been investigated. In total, 317 samples were collected. The dataset was analyzed according to the main air mass inflow at the station. We found that remote conditions make up about 45% of the meteorological conditions in a year at CVAO and thus the northern tropical Atlantic. Surprisingly, air masses from North America are often responsible for higher trace metal concentrations in this region. Elements such as Zn, Pb, Cu, Cr, Ni, and V were mostly found in the submicron size fractions, while elements with dominant crustal or oceanic origin such as Fe, Ti, Mn, Sr, and Rb were found in the coarse fractions (>1 μm. The highest metal concentrations, especially for Zn (3.23 ng m−3, Cu (0.81 ng m−3, Sr (2.63 ng m−3, and Cr (0.53 ng m−3, were observed in air masses originating from North America and the concentrations were within the same concentration range to those reported previously in the literature for remote marine aerosols. Fe (12.26 ng m−3, Ti (0.91 ng m−3, and Mn (0.35 ng m−3 showed higher concentrations when air mass came from Europe and the Canary Islands. Pb concentration was low (−3 and did not vary significantly with air mass direction. The low Pb concentration is indicative of the complete phase-out of leaded gasoline even in African countries. Crustal enrichment factor values decreased from fine to coarse-mode particles with low values (20 for Zn, Cu, Ni, Cr, Pb, and Se. The observed enrichment of the elements was attributed to crustal, marine, anthropogenic, and

  10. Determinants of public support for threatened and endangered species management: A case study of Cape Lookout National Seashore

    Science.gov (United States)

    Le, Lena; Bagstad, Kenneth J.; Cook, Philip S.; Leong, Kirsten M.; DiDonato, Eva

    2015-01-01

    Gaining public support for management actions is important to the success of public land management agencies’ efforts to protect threatened and endangered species. This is especially relevant at national parks, where managers balance two aspects of their conservation mission: to protect resources and to provide for public enjoyment. This study examined variables potentially associated with support for management actions at Cape Lookout National Seashore, a unit of the National Park Service. Two visitor surveys were conducted at the park at different seasons, and a resident survey was conducted for households in Carteret County, North Carolina, where the park is located. The goal of the project was to provide park managers with information that may help with the development of communication strategies concerning the park’s conservation mission. These communication strategies may help to facilitate mutual understanding and garner public support for management actions. Several variables were examined as potential determinants that park managers ought to consider when developing communication strategies. Multinomial logistic regression was applied to examine the relationships between these variables and the likelihood of support for or opposition to management actions. The variables examined included perceived shared values of park resources, general environmental attitudes, level of familiarity with park resources and regulations, knowledge about threatened and endangered species, level of trust in the decision-making process, and perceived shared values with park management. In addition, demographic variables such as income level, respondent age, residency status, and visitor type were also used. The results show that perceived values of threatened and endangered species, trust in park managers and the decision-making process, and perceived share values with park managers were among the strongest indicators of support for management actions. Different user groups

  11. Rock stability analysis – A case study

    Directory of Open Access Journals (Sweden)

    Lahmili A.

    2018-01-01

    Full Text Available The problems of the stability of the mineral-bearing structure ST2 at 560 m of depth in the east zone of Bou-azzer mine disturbs the advance of the exploitation. The geological and structural study based on field observations and the analysis of core drilling shows the presence of altered and fractured diorite surmounted by cobalt mineralization. Based on the empirical methods of Barton (Q-system and Bieniawski (RMR the bed rock is classified as poor quality. The analytical study made it possible to dimension supporting by bow-pieces and bolting. The existence of several types of discontinuities (fault, diaclases and joints has made the realization of numerical simulation by the finite elements method very difficult. These discontinuities create a network of natural fractures which cut out the blocks in various forms likely to be detached or slip into the excavation, thus encouraging the infiltration of water creating pressure on the massif. The classical studies show their limits in practice for installation of supporting because they must take into account the characteristics of discontinuities. Hence a structural analysis of the massif is essential. The cracking survey of ST2 at 560 m of depth in the east zone of Bou-azzer mine at 560m of depth, and their processing by the DIPS software, showed the existence of three main families of discontinuity NW-SE with a dip of 75SW, NS subverticale and NE-SW with a dip of 57NW, and two families of minor joints NW-SE and NE-SW with successive dips of 40SW and 75SE. The analysis of fracturing surveys allowed us to evaluate the risks of falling blocks and the families of discontinuity responsible for them, and to limit the zones presenting a risk of slip and the families responsible for them. The importance of this study is of knowing how and where to put supporting to be opposed to the risk of fall and tilting of the blocks, caused by the network of discontinuities of the massif.

  12. Accelerating Vaccine Formulation Development Using Design of Experiment Stability Studies.

    Science.gov (United States)

    Ahl, Patrick L; Mensch, Christopher; Hu, Binghua; Pixley, Heidi; Zhang, Lan; Dieter, Lance; Russell, Ryann; Smith, William J; Przysiecki, Craig; Kosinski, Mike; Blue, Jeffrey T

    2016-10-01

    Vaccine drug product thermal stability often depends on formulation input factors and how they interact. Scientific understanding and professional experience typically allows vaccine formulators to accurately predict the thermal stability output based on formulation input factors such as pH, ionic strength, and excipients. Thermal stability predictions, however, are not enough for regulators. Stability claims must be supported by experimental data. The Quality by Design approach of Design of Experiment (DoE) is well suited to describe formulation outputs such as thermal stability in terms of formulation input factors. A DoE approach particularly at elevated temperatures that induce accelerated degradation can provide empirical understanding of how vaccine formulation input factors and interactions affect vaccine stability output performance. This is possible even when clear scientific understanding of particular formulation stability mechanisms are lacking. A DoE approach was used in an accelerated 37(°)C stability study of an aluminum adjuvant Neisseria meningitidis serogroup B vaccine. Formulation stability differences were identified after only 15 days into the study. We believe this study demonstrates the power of combining DoE methodology with accelerated stress stability studies to accelerate and improve vaccine formulation development programs particularly during the preformulation stage. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  13. Equations for studies of feedback stabilization

    International Nuclear Information System (INIS)

    Boozer, A.H.

    1998-01-01

    Important ideal magnetohydrodynamic (MHD) instabilities grow slowly when a conducting wall surrounds a toroidal plasma. Feedback stabilization of these instabilities may be required for tokamaks and other magnetic confinement concepts to achieve adequate plasma pressure and self-driven current for practical fusion power. Equations are derived for simulating feedback stabilization, which require the minimum information about an ideal plasma for an exact analysis. The equations are solved in the approximation of one unstable mode, one wall circuit, one feedback circuit, and one sensor circuit. The analysis based on a single unstable mode is shown to be mathematically equivalent to the standard analysis of feedback of the axisymmetric vertical instability of tokamaks. Unlike that analysis, the method presented here applies to multiple modes that are coupled by the wall and to arbitrary toroidal mode numbers. copyright 1998 American Institute of Physics

  14. Suitability of ‘Guidelines for Screening of Prosthetic Candidates: Lower Limb’ for the Eastern Cape, South Africa: A qualitative study

    Directory of Open Access Journals (Sweden)

    Luphiwo L. Mduzana

    2018-01-01

    Full Text Available Background: Major lower limb amputation has a severe impact on functional mobility. Mobility can be salvaged with a prosthesis, but this is not always the best option. It is often difficult to decide whether to refer someone for a prosthesis or not. A prosthetic screening tool ‘Guidelines for Screening of Prosthetic Candidates: Lower Limb’ was developed and is used for prosthetic prescription in parts of the Western Cape province of South Africa.Objectives: This study aimed to explore the suitability of the tool ‘Guidelines for Screening of Prosthetic Candidates: Lower Limb’ for use in the Eastern Cape province of South Africa.Method: A qualitative study was conducted with conveniently sampled occupational therapists (OTs (n = 10, physiotherapists (PTs (n = 12 and prosthetists (n = 6 in government employment in the Buffalo City Metro Municipality. Participants were trained in the use of the tool and used it for four weeks with patients. Their experiences of the tool were assessed through three focus group discussions with emergent themes being identified during inductive data analysis.Findings: Participants indicated that the tool could assist with prosthetic prescription, goal setting, communication and teamwork. They thought that the tool was multidisciplinary in nature, comprehensive and practical. Findings showed a lack of teamwork in this study setting. Resistance to change and a lack of time might also hamper implementation of the tool.Conclusion: The tool can assist with managing the backlog for prostheses and to guide prosthetic prescription in the Eastern Cape province.Clinical implications: A prosthesis can help to salvage functional mobility after lower limb amputation. However, not all people who had above knee amputation manage to walk with a prosthesis. The tool reported on in this article provides information that can guide prosthetic prescription and rehabilitation goals.

  15. Comprehensive studies of the Arctic natural environment on the Research station "Ice Base "Cape Baranov " in 2014 - 2016 years and plans for future

    Science.gov (United States)

    Sokolov, Vladimir; Makshtas, Alexander; Borodkin, Vladimir; Laurila, Tuomas; Asmi, Ejia; Popovicheva, Olga

    2017-04-01

    Research Station "Ice base "Cape Baranov" of Arctic and Antarctic Research Institute (AARI) was opened in the fall 2013 on the Bolshevik Island, Archipelago Severnaya Zemlia. Presently in the observatory comprehensive studies in practically all areas of Earth Sciences are conducted. During 2014 - 2016 years about 30 scientists and technicians carried out standard and special meteorological, radiation and upper-air observations, including studies of ozone in troposphere and lower stratosphere; investigations of turbulent and radiation energy - mass exchange between surface and atmosphere; measurements of greenhouse gases concentrations, chemical composition of precipitation, aerosol research (including black carbon); investigations of the active soil layer, morphological characteristics and physical - mechanical processes in fast ice; oceanographic and hydrochemical studies in the Shokalski Strait; hydrological studies of small rivers and lakes; glaciological and paleogeographic studies; ecological studies of natural objects in the region of "Ice Base" Cape Baranov". In 2017 there are plans for organization of greenhouse gases fluxes measurements from tundra (together with Korean Polar Research Institute) and installation of high-resolution ground-based remote sensing systems SODAR, RASS, and ceilometer (together with Trier University, Germany). This study is supported by CNTP 1.5.3.3 of Roshydromet and Project 2017-14-588-0005-003 of the Ministry of education and science of the Russian Federation

  16. Detailed nuclear structure studies far from stability

    International Nuclear Information System (INIS)

    Wood, J.L.; Schwarzenberg, J.; Zganjar, E.F.; Rupnik, D.

    1991-01-01

    State-of--the-art spectroscopy of nuclei far from stability has achieved an extraordinary level of sophistication and detail in the last ten years. In principle, if a state can be populated, it can be characterized by its energy, spin, parity, and major decay paths. Sometimes its lifetime can be measured. In practice, one is confronted with enormous complexity. To convert raw spectroscopic data into nuclear structure data involves a complex process of disentangling gamma rays and conversion electrons into decay schemes. Specifically, coincidence techniques, especially coincidence intensities, play a crucial role in this process. Recent examples and methods from work done at UNISOR are presented

  17. Immunisation coverage in the rural Eastern Cape – are we getting the basics of primary care right? Results from a longitudinal prospective cohort study

    Directory of Open Access Journals (Sweden)

    K le Roux

    2017-01-01

    Full Text Available Background. Immunisations are one of the most cost-effective public health interventions available and South Africa (SA has implemented a comprehensive immunisation schedule. However, there is disagreement about the level of immunisation coverage in the country and few studies document the immunisation coverage in rural areas. Objective. To examine the successful and timely delivery of immunisations to children during the first 2 years of life in a deeply rural part of the Eastern Cape Province of SA. Methods. From January to April 2013, a cohort of sequential births (N=470 in the area surrounding Zithulele Hospital in the OR Tambo District of the Eastern Cape was recruited and followed up at home at 3, 6, 9, 12 and 24 months post birth, up to May 2015. Immunisation coverage was determined using Road-to-Health cards. Results. The percentages of children with all immunisations up to date at the time of interview were: 48.6% at 3 months, 73.3% at 6 months, 83.9% at 9 months, 73.3% at 12 months and 73.2% at 24 months. Incomplete immunisations were attributed to stock-outs (56%, lack of awareness of the immunisation schedule or of missed immunisations by the mother (16% and lack of clinic attendance by the mother (19%. Of the mothers who had visited the clinic for baby immunisations, 49.8% had to make multiple visits because of stock-outs. Measles coverage (of at least one dose was 85.2% at 1 year and 96.3% by 2 years, but 20.6% of babies had not received a second measles dose (due at 18 months by 2 years. Immunisations were often given late, particularly the 14-week immunisations. Conclusions. Immunisation rates in the rural Eastern Cape are well below government targets and indicate inadequate provision of basic primary care. Stock-outs of basic childhood immunisations are common and are, according to mothers, the main reason for their children’s immunisations not being up to date. There is still much work to be done to ensure that the basics of

  18. Physico-Chemical Stability Studies of Neem (Azadirachta indica ...

    African Journals Online (AJOL)

    Nekky Umera

    present study, neem oil had been extracted from the ripe seed of Azadirachta indica (A. juss) plant. The oil was ... stability is not a problem for neem oil in a vanishing cream base formulation. Keywords: Neem oil, Stability, Shelf life, ... The containers were covered with filter paper and the solvent was allowed to evaporate.

  19. Experimental study of flame stability in biogas premix system

    International Nuclear Information System (INIS)

    Diaz G, Carlos A; Amell A Andres; Cardona Luis F

    2008-01-01

    Utilization of new renewable energy sources have had a special interest in last years looking for decrease the dependence of fossil fuels and the environmental impact generated for them. This work studies experimentally the flame stability of a simulated biogas with a volumetric composition of 60% methane and 40% carbon dioxide. The objective of this study is to obtain information about design and interchangeability of gases in premixed combustion systems that operate with different fuel gases. The critical velocity gradient was the stability criteria used. Utilization of this criteria and the experimental method followed, using a partial premixed burner, stability flame diagram of biogas studied had been obtained. Presence of carbon dioxide has a negative effect in flame stability, decreasing significantly the laminar flame speed and consequently, the stability range of biogas burners because of apparition of blow off.

  20. Study of the 50 mg Propylthiouracil tablets stability

    International Nuclear Information System (INIS)

    Valdes Bendoyro, Maria Olga; Garcia Penna, Caridad Margarita; Lugones Fernandez, Juan

    2010-01-01

    Authors developed a stability study of 50 mg Propylthiouracil tablets and determination of its expiry date. This study was conducted by fixed life methods and of accelerated stability by high-performance liquid chromatography, validated in Drugs Research and Development Center. Fixed life study was conducted during 24 months at room temperature; whereas the accelerated stability study was conducted exposing the product to light influence, humidity and temperature; during 3 months a analysis was performed for the two first ones and over 6 months in the case of temperature study. Propylthiouracil formula (50 mg tablets) fulfilled the quality specifications described in Pharmacopeia. Results of stability study by fixed life after 24 months showed that thr product maintain the parameter determining its quality during this period, and in the accelerated studies there was not a significant degradation of product. Two years was the expity date established in above mentioned conditions

  1. "I passed the test!" Evidence of diagnostic misconception in the recruitment of population controls for an H3Africa genomic study in Cape Town, South Africa.

    Science.gov (United States)

    Masiye, Francis; Mayosi, Bongani; de Vries, Jantina

    2017-02-15

    Advances in genetic and genomic research have introduced challenges in obtaining informed consent for research in low and middle-income settings. However, there are only few studies that have explored challenges in obtaining informed consent in genetic and genomic research in Africa and none in South Africa. To start filling this gap, we conducted an empirical study to investigate the efficacy of informed consent procedures for an H3Africa genomic study on Rheumatic Heart Disease (RHDGen) at the University of Cape Town in South Africa. The main aim of the study was to understand ethical challenges in obtaining informed consent in the RHDGen study. We used a qualitative study methodology involving in-depth interviews and participant observations. Our study participants were RHDGen cases (patients), healthy controls and research staff involved in the recruitment of RHDGen cases and controls. In total, we conducted 32 in-depth interviews with RHDGen cases and controls, 2 in-depth interviews with research staff and 57 direct observations of the consent procedures of RHDGen cases and controls. The interviews were conducted in English, audio-recorded and transcribed verbatim. Data were analyzed using thematic content analysis. The study was conducted in 3 sites within Cape Town, South Africa. Most healthy controls joined the RHDGen study in order to be screened for rheumatic heart disease (diagnostic misconception). A majority of RHDGen cases decided to join the RHDGen study because of therapeutic misconception. The ethical challenges that impacted on obtaining informed consent in the RHDGen study were complex. In this study, the main challenges were diagnostic misconception among RHDGen controls and therapeutic misconception among RHDGen cases.

  2. Non-parametric approach to the study of phenotypic stability.

    Science.gov (United States)

    Ferreira, D F; Fernandes, S B; Bruzi, A T; Ramalho, M A P

    2016-02-19

    The aim of this study was to undertake the theoretical derivations of non-parametric methods, which use linear regressions based on rank order, for stability analyses. These methods were extension different parametric methods used for stability analyses and the result was compared with a standard non-parametric method. Intensive computational methods (e.g., bootstrap and permutation) were applied, and data from the plant-breeding program of the Biology Department of UFLA (Minas Gerais, Brazil) were used to illustrate and compare the tests. The non-parametric stability methods were effective for the evaluation of phenotypic stability. In the presence of variance heterogeneity, the non-parametric methods exhibited greater power of discrimination when determining the phenotypic stability of genotypes.

  3. Study of mine stability using records of ground tilting

    CSIR Research Space (South Africa)

    Spottiswoode, SM

    2006-06-01

    Full Text Available -carrying capacity of the pillars. Physical measurements of pillar deformations were deemed necessary. Towards this end, the use of ground ARMA/USRMS 06-1168 A study of mine stability...

  4. Stabilization

    Directory of Open Access Journals (Sweden)

    Muhammad H. Al-Malack

    2016-07-01

    Full Text Available Fuel oil flyash (FFA produced in power and water desalination plants firing crude oils in the Kingdom of Saudi Arabia is being disposed in landfills, which increases the burden on the environment, therefore, FFA utilization must be encouraged. In the current research, the effect of adding FFA on the engineering properties of two indigenous soils, namely sand and marl, was investigated. FFA was added at concentrations of 5%, 10% and 15% to both soils with and without the addition of Portland cement. Mixtures of the stabilized soils were thoroughly evaluated using compaction, California Bearing Ratio (CBR, unconfined compressive strength (USC and durability tests. Results of these tests indicated that stabilized sand mixtures could not attain the ACI strength requirements. However, marl was found to satisfy the ACI strength requirement when only 5% of FFA was added together with 5% of cement. When the FFA was increased to 10% and 15%, the mixture’s strength was found to decrease to values below the ACI requirements. Results of the Toxicity Characteristics Leaching Procedure (TCLP, which was performed on samples that passed the ACI requirements, indicated that FFA must be cautiously used in soil stabilization.

  5. The transport of atmospheric sulfur over Cape Town

    Science.gov (United States)

    Jenner, Samantha L.; Abiodun, Babatunde J.

    2013-11-01

    Cape Town, renowned for its natural beauty, is troubled by an unpleasant brown haze pollution, in which atmospheric sulfur plays a major role. This study investigates whether Cape Town is a net producer or recipient of anthropogenic sulfur pollution. In the study, two atmospheric chemistry-transport models (RegCM and WRF) are used to simulate atmospheric flow and chemistry transport over South Africa for two years (2001 and 2002). Both models reproduce the observed seasonal variability in the atmospheric flow and SO2 concentration over Cape Town. The models simulations agree on the seasonal pattern of SO2 over South Africa but disagree on that of SO4. The simulations show that ambient sulfur in Cape Town may be linked with pollutant emissions from the Mpumalanga Highveld, South Africa's most industrialized region. While part of atmospheric SO2 from the Highveld is transported at 700 hPa level toward the Indian Ocean (confirming previous studies), part is transported at low level from the Highveld toward Cape Town. In April, a band of high concentration SO2 extends between the Highveld and Cape Town, following the south coast. Extreme sulfur pollution events in Cape Town are associated with weak flow convergence or stagnant conditions over the city, both of which encourage the accumulation of pollution. However the study suggests that atmospheric sulfur is being advected from Mpumalanga Highveld to Cape Town and this may contribute to atmospheric pollution problems in Cape Town.

  6. A framework for effective collaboration: a case study of collaboration in nursing education in the Western Cape, South Africa.

    Science.gov (United States)

    Daniels, Felicity M; Khanyile, Thembisile D

    2013-09-01

    A fundamental purpose of mergers between higher education institutions (HEIs) in 2002 was to enable sharing of scarce resources between more advanced universities and those historically disadvantaged by the apartheid system of the South African Government. A common teaching platform for undergraduate nursing education in the Western Cape was established in 2005, in line with the transformation of the higher education system, as a collaborative initiative between three universities. In order to evaluate the common teaching platform, Stuffelbeam's context, input, process, product (CIPP) research model was employed. A sample of 108 participants was selected through stratified purposive sampling, and included three deputy vice-chancellors, three deans, three heads of department, 18 lecturers and 81 students. Semi-structured interviews were held with the staff members, whilst the students participated in focus group interviews. Open-ended questions informed by literature and the CIPP evaluation model were developed and used to guide the interviews. This enabled the researcher to obtain a rich description of the participants' experiences. The data were analysed inductively. The results revealed that the main purpose of collaboration was not achieved due to the lack of a common understanding of the concept of collaboration and its purpose; a lack of readiness to collaborate and a lack of sharing of resources. A framework for effective collaboration was developed based on the results. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Dietary Intake of the Urban Black Population of Cape Town: The Cardiovascular Risk in Black South Africans (CRIBSA Study

    Directory of Open Access Journals (Sweden)

    Nelia P. Steyn

    2016-05-01

    Full Text Available Introduction: To determine dietary intake of 19 to 64 years old urban Africans in Cape Town in 2009 and examine the changes between 1990 and 2009. Methods: A representative cross-sectional sample (n = 544, stratified by gender and age was randomly selected in 2009 from the same areas sampled in 1990. Socio-demographic data and a 24-h dietary recall were obtained by trained field workers. The associations of dietary data with an asset index and degree of urbanization were assessed. Results: Fat intakes were higher in 19–44-year-old men (32% energy (E and women (33.4%E in 2009 compared with 1990 (men: 25.9%E, women: 27.0%E while carbohydrate intakes were lower in 2009 (men 53.2%E, women: 55.5%E than in 1990 (men: 61.3%E; women: 62%E while sugar intake increased significantly (p < 0.01 in women. There were significant positive correlations between urbanization and total fat (p = 0.016, saturated fat (p = 0.001, monounsaturated fat (p = 0.002 and fat as a %E intake (p = 0.046. Urbanization was inversely associated with intake of carbohydrate %E (p < 0.001. Overall micronutrient intakes improved significantly compared with 1990. It should also be noted that energy and macronutrient intakes were all significant in a linear regression model using mean adequacy ratio (MAR as a measure of dietary quality in 2009, as was duration of urbanization. Discussion: The higher fat and lower carbohydrate %E intakes in this population demonstrate a transition to a more urbanized diet over last two decades. These dietary changes reflect the nutrition transitions that typically occur as a longer time is spent in urban centers.

  8. Differential obesity indices identify the metabolic syndrome in Black men and women in Cape Town: the CRIBSA study.

    Science.gov (United States)

    Peer, N; Steyn, K; Levitt, N

    2016-03-01

    To determine the obesity indices, specifically waist circumference (WC), that identified ≥2 other metabolic syndrome (MS) components (2009 criteria) in 25- to 74-year-old Africans in Cape Town. Data were collected from a cross-sectional sample by administered questionnaires, clinical measurements and biochemical analyses. The obesity cut points were estimated by the Youden Index. Logistic regression analyses determined whether obesity cut points identifying ≥2 MS components occurred at true inflection points. Among the 1099 participants, the calculated cut points and 95% confidence intervals (CI) were: men, WC 83.9 cm (81.6-86.2), waist-to-hip ratio (WHR) 0.89 (0.87-0.90), waist-to-height ratio (WHtR) 0.50 (0.48-0.52) and body mass index (BMI) 24.1 kg/m(2) (22.0-26.1); women, WC 94.0 cm (92.6-95.3), WHR 0.85 (0.83-0.87), WHtR 0.59 (0.57-0.60) and BMI 32.1 kg/m(2) (29.7-34.6). Raised WC was significantly associated with ≥2 MS components in men: WC 84.0-93.9 cm (odds ratio (OR): 3.19, 95% confidence interval (CI): 1.73-5.85) and WC ≥94.0 cm (OR: 8.50, 95% CI: 4.44-16.25) compared with WC obesity (OR: 3.60, 95% CI: 1.82-7.10) but not overweight (P = 0.063) was significantly associated with ≥2 MS components. Obesity cut points for Africans should be re-evaluated and adjusted accordingly. © The Author 2015. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Numerical Study on Soil Arching Effects of Stabilizing Piles

    OpenAIRE

    Fan, Fusong; Chen, Guangqi; Hu, Xinli; Wang, Wei

    2015-01-01

    The Soil arching effect, the transfer of soil pressure from the yielding soil to the piles support, is a phenomena commonly encountered in geotechnical engineering for stabilizing landslides. In this paper, the (finite element method) FEM and (discontinuous deformation analysis) DDA were used to study on the soil arching effects of stabilizing piles in landslides. This paper proposes a method for two dimensional numerical simulation to perform three dimensional soil-pile interaction so that t...

  10. Properties and CAPE

    DEFF Research Database (Denmark)

    Gani, Rafiqul; O'Connell, J.P.

    2001-01-01

    The role of properties in the solution of Computer Aided Process Engineering (CAPE) problems is described in terms of current trend, future challenges and important issues. Three distinct roles of properties in CAFE have been identified - a service role, a service plus advice role and a service......, advice plus solve role. The CAFE problems solved under each of these roles are described together with simple illustrative examples. Finally, the paper describes how some of the future problems related to integration of synthesis, design and control might be dealt with efficiently and reliably through co......-operative CAFE and properties methodologies. (C) 2001 Elsevier Science Ltd. All rights reserved....

  11. Importance of the different posterolateral knee static stabilizers: biomechanical study

    Directory of Open Access Journals (Sweden)

    Rodrigo Campos Pace Lasmar

    2010-01-01

    Full Text Available PURPOSE: The purpose of this study was to evaluate the relative importance of the different static stabilizers of the posterolateral corner of the knee in cadavers. METHODS: Tests were performed with the application of a varus and external rotation force to the knee in extension at 30 and 60 degrees of flexion using 10 cadaver knees. The forces were applied initially to an intact knee and then repeated after a selective sectioning of the ligaments into the following: section of the lateral collateral ligament; section of the lateral collateral ligament and the popliteofibular complex; and section of the lateral collateral ligament, the popliteofibular complex and the posterolateral capsule. The parameters studied were the angular deformity and stiffness when the knees were submitted to a 15 Newton-meter varus torque and a 6 Newton-meter external tibial torque. Statistical analysis was performed using the ANOVA (Analysis of Variance and Tukey's tests. RESULTS AND CONCLUSION: Our findings showed that the lateral collateral ligament was important in varus stability at 0, 30 and 60 degrees. The popliteofibular complex was the most important structure for external rotation stability at all angles of flexion and was also important for varus stability at 30 and 60 degrees. The posterolateral capsule was important for varus stability at 0 and 30 degrees and for external rotation stability in extension. Level of evidence: Level IV (cadaver study.

  12. Implementing community participation through legislative reform: a study of the policy framework for community participation in the Western Cape province of South Africa.

    Science.gov (United States)

    Meier, Benjamin Mason; Pardue, Caitlin; London, Leslie

    2012-08-25

    Amidst an evolving post-apartheid policy framework for health, policymakers have sought to institutionalize community participation in Primary Health Care, recognizing participation as integral to realizing South Africa's constitutional commitment to the right to health. With evolving South African legislation supporting community involvement in the health system, early policy developments focused on Community Health Committees (HCs) as the principal institutions of community participation. Formally recognized in the National Health Act of 2003, the National Health Act deferred to provincial governments in establishing the specific roles and functions of HCs. As a result, stakeholders developed a Draft Policy Framework for Community Participation in Health (Draft Policy) to formalize participatory institutions in the Western Cape province. With the Draft Policy as a frame of analysis, the researchers conducted documentary policy analysis and semi-structured interviews on the evolution of South African community participation policy. Moving beyond the specific and unique circumstances of the Western Cape, this study analyzes generalizable themes for rights-based community participation in the health system. Framing institutions for the establishment, appointment, and functioning of community participation, the Draft Policy proposed a formal network of communication - from local HCs to the health system. However, this participation structure has struggled to establish itself and function effectively as a result of limitations in community representation, administrative support, capacity building, and policy commitment. Without legislative support for community participation, the enactment of superseding legislation is likely to bring an end to HC structures in the Western Cape. Attempts to realize community participation have not adequately addressed the underlying factors crucial to promoting effective participation, with policy reforms necessary: to codify clearly

  13. A rock- and palaeomagnetic study of recent lavas and 1995 volcanic glass on Fogo (Cape Verde Islands)

    DEFF Research Database (Denmark)

    Knudsen, M.F.; Abrahamsen, N.; Riisager, P.

    2005-01-01

    Fogo is the only island in the Cape Verde archipelago with accounts of historical volcanic activity.Here we present palaeomagnetic data from seven geologically recent lava flows on Fogo, including one glassy, volcanic flow from the eruption in 1995. Almost all samples behaved well during...... pseudo-single-domain (PSD) behaviour, whereas the hysteresis parameters for the glassy flow unit tend to plot in a region associated with mixtures of superparamagnetic (SP) and singledomain(SD) grains. Despite historical accounts of the eruptive activity on Fogo it was impossible toobtain unique...... correlations between the historical flow flelds and the non-glassy flow units presented in this study. One of six non-glassy flow units yields a direction consistent with existing approximative reference curves for the historical secular variation on Fogo. Consequently, we suspect that some of the non...

  14. Risk factors for meningococcal disease in Cape Town | Moodley ...

    African Journals Online (AJOL)

    Objective. To determine the risk factors associated with meningococcal disease among children living in Cape Town. Design. A case-control study was conducted from October 1993 to January 1995. Setting. The study population consisted of all children tmder the age of 14 years who were resident in the Cape Town ...

  15. Surviving gangs, violence and racism in cape town

    DEFF Research Database (Denmark)

    Lindegaard, Marie Rosenkrantz

    Surviving Gangs, Violence and Racism in Cape Town offers an ethnographic study of young men in Cape Town and considers how they stay safe in when growing up in post-apartheid South Africa. Breaking away from previous studies looking at structural inequality and differences, this unique book focuses...

  16. Study of orbit stability in the SSRF storage ring

    International Nuclear Information System (INIS)

    Dai Zhimin; Liu Guimin; Huang Nan

    2003-01-01

    In this paper, analysis of the beam orbit stability and conceptual study of the dynamic orbit feedback in the SSRF storage ring are presented. It is shown that beam orbit position movement at the photon source points is smaller than the orbit stability requirements in horizontal plane, but exceeds the orbit stability requirements in vertical plane. A dynamic global orbit feedback system, which consists of 38 high-bandwidth air-coil correctors and 40 high-precise BPMs, is proposed to suppress the vertical beam orbit position movement. Numerical simulations show that this dynamic orbit feedback system can stabilize the vertical beam orbit position movement in the frequency range up to 100 Hz

  17. Prevalence of Taenia solium cysticercosis in swine from a community-based study in 21 villages of the Eastern Cape Province, South Africa.

    Science.gov (United States)

    Krecek, R C; Michael, L M; Schantz, P M; Ntanjana, L; Smith, M F; Dorny, P; Harrison, L J S; Grimm, F; Praet, N; Willingham, A L

    2008-06-14

    The pork tapeworm, Taenia solium, causative organism of porcine cysticercosis and human neurocysticercosis is known to occur in areas of South Africa including Eastern Cape Province but, despite increasing reports of its occurrence throughout the subregion, the prevalence is yet to be clearly established. The parasite presents a potentially serious agricultural problem and public health risk in endemic areas. The human populations considered to be at highest risk of infection with this zoonotic helminth are people living in rural areas most of whom earn their livelihood wholly or partially through livestock rearing. Here we report on initial results of a community-based study of pigs owned by resource-poor, emerging pig producers from 21 villages in the Eastern Cape Province. Lingual examination (tongue palpation) in live pigs, two enzyme-linked immunosorbent assays (ELISAs), which detect parasite antigen (B158/B60 Ag-ELISA and HP10 Ag-ELISA) and an enzyme immunotransfer blot (EITB) assay, which detects antiparasite antibody, were used to verify endemicity and estimate apparent prevalence. In the absence of a gold standard true prevalence was obtained, using a Bayesian approach, with a model that uses both available data and prior information. Results indicate that the parasite is indeed present in the study villages and that true prevalence was 64.6%. The apparent prevalences as measured by each of the four tests were: 11.9% for lingual examination, 54.8% for B158/B60 Ag-ELISA, 40.6% for HP10 Ag-ELISA and 33.3% for EITB. This base-line knowledge of the prevalence of T. solium in pigs provides information essential to the design and monitoring of sustainable and appropriate interventions for cysticercosis prevention and control.

  18. The functioning of primary school learners with paraplegia/paraparesis in mainstream schools in the Western Cape, South Africa. An exploratory study.

    Science.gov (United States)

    Vosloo, San-Marie

    2009-01-01

    This study explores the reality of implementing policy guidelines that promote the inclusion of learners with disabilities in mainstream schools. According to the department of education in South Africa, learners who can satisfactorily be educated in an ordinary or mainstream school should be accommodated there. The Craig handicap assessment and reporting technique were used to identify activity limitations and participation restrictions of learners with paraplegia/paraparesis in the mainstream school setting in the Western Cape, South Africa. The Craig hospital inventory of environmental factors identified contextual factors that facilitate or restrict the participation of learners. The views of the learners, teachers and parents were compared in order to identify the facilitators and barriers that influence the participation of physically disabled learners in mainstream schooling. The study population comprised 15 learners between the ages of 6 and 14 years old with paraplegia/paraparesis, their parents and relevant class teachers in 13 mainstream schools of the Western Cape, South Africa. Findings indicate that cognitive independence and mobility are the two areas that most restricted the participation of the learners in the school. Resource availability, social support and equality were critical to facilitating the inclusion of learners at mainstream schools. It is recommended that a comprehensive research project be undertaken. Teacher support and training is essential for keeping the educators motivated and informed. Physical assistance to the learners should be provided in a structured and appropriate way. Physical accessibility, transport and medical information should be addressed at the institutional (school) level and is not the responsibility of the parents or caregivers of the disabled learners.

  19. Bechevin Bay, Alaska, Inlet Stability Study.

    Science.gov (United States)

    1985-05-01

    Krenitzin. Bechevin Inlet, Bechevin Bay, and Isanotski Strait form an inlet system which * separates Unimak Island from the Alaska Peninsula. This...from the North Pacific must travel around Unimak Island through Unimak Pass. This route is 100-150 miles longer than the route through the Bechevin...period was semidiurnal, while the tidal flow at Unimak Pass (not too far southwest from the study area) was, interestingly, diurnal. Second, the phase

  20. Gamma radiation stability studies of mercury fulminate

    International Nuclear Information System (INIS)

    Fondeur, F.F.

    2000-01-01

    Mercury fulminate completely decomposed in a gamma source (0.86 Mrad/h) after a dose of 208 Mrad. This exposure equates to approximately 2.4 years in Tank 15H and 4 years in Tank 12H, one of the vessels of concern. Since the tanks lost the supernatant cover layer more than a decade ago, this study suggests that any mercury fulminate or closely related energetic species decomposed long ago if ever formed

  1. Gamma radiation stability studies of mercury fulminate

    Energy Technology Data Exchange (ETDEWEB)

    Fondeur, F.F.

    2000-02-17

    Mercury fulminate completely decomposed in a gamma source (0.86 Mrad/h) after a dose of 208 Mrad. This exposure equates to approximately 2.4 years in Tank 15H and 4 years in Tank 12H, one of the vessels of concern. Since the tanks lost the supernatant cover layer more than a decade ago, this study suggests that any mercury fulminate or closely related energetic species decomposed long ago if ever formed.

  2. Stability study in one step steam generators

    International Nuclear Information System (INIS)

    Abbate, P.

    1990-01-01

    The TWO program is presented developed for the behaviour limit calculation stable in one step steam generators for the case of Density Waves phenomenom. The program is based on a nodal model which, using Laplace transformation equations, allows to study the system's transfer functions and foresee the beginning of the unstable behaviour. This program has been satisfactorily validated against channels data uniformly heated in the range from 4.0 to 6.0 Mpa. Results on the CAREM reactor's steam generator analysis are presented. (Author) [es

  3. A prospective cohort study on ambient air pollution and respiratory morbidities including childhood asthma in adolescents from the western Cape Province: study protocol

    Directory of Open Access Journals (Sweden)

    Toyib Olaniyan

    2017-09-01

    Full Text Available Abstract Background There is evidence from existing literature that ambient air pollutant exposure in early childhood likely plays an important role in asthma exacerbation and other respiratory symptoms, with greater effect among asthmatic children. However, there is inconclusive evidence on the role of ambient air pollutant exposures in relation to increasing asthma prevalence as well as asthma induction in children. At the population level, little is known about the potential synergistic effects between pollen allergens and air pollutants since this type of association poses challenges in uncontrolled real life settings. In particular, data from sub-Sahara Africa is scarce and virtually absent among populations residing in informal residential settlements. Methods/design A prospective cohort study of 600 school children residing in four informal settlement areas with varying potential ambient air pollutant exposure levels in the Western Cape in South Africa is carried-out. The study has two follow-up periods of at least six-months apart including an embedded panel study in summer and winter. The exposure assessment component models temporal and spatial variability of air quality in the four study areas over the study duration using land-use regression modelling (LUR. Additionally, daily pollen levels (mould spores, tree, grass and weed pollen in the study areas are recorded. In the panel study asthma symptoms and serial peak flow measurements is recorded three times daily to determine short-term serial airway changes in relation to varying ambient air quality and pollen over 10-days during winter and summer. The health outcome component of the cohort study include; the presence of asthma using a standardised ISAAC questionnaire, spirometry, fractional exhaled nitric-oxide (FeNO and the presence of atopy (Phadiatop. Discussion This research applies state of the art exposure assessment approaches to characterize the effects of ambient air

  4. A prospective cohort study on ambient air pollution and respiratory morbidities including childhood asthma in adolescents from the western Cape Province: study protocol.

    Science.gov (United States)

    Olaniyan, Toyib; Jeebhay, Mohamed; Röösli, Martin; Naidoo, Rajen; Baatjies, Roslynn; Künzil, Nino; Tsai, Ming; Davey, Mark; de Hoogh, Kees; Berman, Dilys; Parker, Bhawoodien; Leaner, Joy; Dalvie, Mohamed Aqiel

    2017-09-16

    There is evidence from existing literature that ambient air pollutant exposure in early childhood likely plays an important role in asthma exacerbation and other respiratory symptoms, with greater effect among asthmatic children. However, there is inconclusive evidence on the role of ambient air pollutant exposures in relation to increasing asthma prevalence as well as asthma induction in children. At the population level, little is known about the potential synergistic effects between pollen allergens and air pollutants since this type of association poses challenges in uncontrolled real life settings. In particular, data from sub-Sahara Africa is scarce and virtually absent among populations residing in informal residential settlements. A prospective cohort study of 600 school children residing in four informal settlement areas with varying potential ambient air pollutant exposure levels in the Western Cape in South Africa is carried-out. The study has two follow-up periods of at least six-months apart including an embedded panel study in summer and winter. The exposure assessment component models temporal and spatial variability of air quality in the four study areas over the study duration using land-use regression modelling (LUR). Additionally, daily pollen levels (mould spores, tree, grass and weed pollen) in the study areas are recorded. In the panel study asthma symptoms and serial peak flow measurements is recorded three times daily to determine short-term serial airway changes in relation to varying ambient air quality and pollen over 10-days during winter and summer. The health outcome component of the cohort study include; the presence of asthma using a standardised ISAAC questionnaire, spirometry, fractional exhaled nitric-oxide (FeNO) and the presence of atopy (Phadiatop). This research applies state of the art exposure assessment approaches to characterize the effects of ambient air pollutants on childhood respiratory health, with a specific focus on

  5. Differing patterns of overweight and obesity among black men and women in Cape Town: the CRIBSA study.

    Science.gov (United States)

    Peer, Nasheeta; Lombard, Carl; Steyn, Krisela; Gwebushe, Nomonde; Levitt, Naomi

    2014-01-01

    To ascertain the prevalence and determinants of overweight/obesity in the 25-74-year-old urban black population of Cape Town and examine the changes between 1990 and 2008/09. In 2008/09, a representative cross-sectional sample, stratified for age and sex, was randomly selected from the same townships sampled in 1990. Data were collected by questionnaires, clinical measurements and biochemical analyses. Gender-specific linear regression models evaluated the associations with overweight/obesity. There were 1099 participants, 392 men and 707 women (response rate 86%) in 2008/09. Mean body mass index (BMI) and waist circumference (WC) were 23.7 kg/m2 (95% confidence interval (CI): 23.1-24.2) and 84.2 cm (95% CI: 82.8-85.6) in men, and 33.0 kg/m2 (95% CI: 32.3-33.7) and 96.8 cm (95% CI: 95.5-98.1) in women. Prevalence of BMI ≥25 kg/m2 and raised WC were 28.9% (95% CI: 24.1-34.3) and 20.1% (95% CI: 15.9-24.9) in men, and 82.8% (95% CI: 79.3-85.9) and 86.0% (95% CI: 82.9-88.6) in women. Among 25-64-year-olds, BMI ≥25 kg/m2 decreased between 1990 (37.3%, 95% CI: 31.7-43.1) and 2008/09 (27.7%, 95% CI: 22.7-33.4) in men but increased from 72.7% (95% CI: 67.6-77.2) to 82.6% (95% CI: 78.8-85.8) in women. In the regression models for men and women, higher BMI was directly associated with increasing age, wealth, hypertension and diabetes but inversely related to daily smoking. Also significantly associated with rising BMI were raised low-density lipoprotein cholesterol and being employed compared to unemployed in men, and having >7 years of education in women. Overweight/obesity, particularly in urban black women, requires urgent action because of the associations with cardiovascular disease risk factors and their serious consequences.

  6. A Numerical Study of A Sea-breeze Front and Its Interaction With The Convective Boundary Layer Over Land During Cape

    Science.gov (United States)

    Hsu, W. R.; Wu, C. C.; Sun, W. Y.

    A sea-breeze front forms at the leading edge of the circulation induced by the con- vective boundary layer over land during daytime. Once the sea-breeze circulation is established, the front usually propagates onshore and sweeps through the convection cells inside the CBL over land near coastal area. The intensity of the front may change from time to time as it merges with those convection cells, while the front also modi- fies the basic characteristics of the CBL (such as surface fluxes, cloud thickness, etc). The interaction between the front and the CBL can be very complicated, and the sit- uation differs from cases to cases with different environmental conditions. With an extensive observation network, the 1991 Convection and Precipitation/Electrification Experiment (CaPE) have documented the phenomenon for several sea-breeze events in southern Florida, USA. In this study, we used the NTU/Purdue nonhydrostatic numerical model to simulate and investigate one of the sea-breeze events during CaPE. The numerical model is quite complete as it includes calculations for Coriolis force, land processes, clouds, the surface similarity equation and a prognostic equation for turbulence kinetic en- ergy in addition to a basic dynamic framework. A major advantage of the model is the use of a forward-backward integration scheme to treat high frequency and internal gravity waves explicitly. The numerical procedure is shown in one of authorsS earlier work to be quite accurate and also free from unstable computational modes. The re- sults showed that the model is capable of reproducing many interesting features of the phenomenon. These features include the CBL development over land, cloud pattern, frontal characteristics, etc. The turbulence and mixing properties of the CBL under the influence of the simulated sea-breeze circulation is discussed in the paper.

  7. Operational demands on pre-hospital emergency care for burn injuries in a middle-income setting: a study in the Western Cape, South Africa.

    Science.gov (United States)

    Allgaier, Rachel L; Laflamme, Lucie; Wallis, Lee A

    2017-12-01

    Burns occur disproportionately within low-socioeconomic populations. The Western Cape Province of South Africa represents a middle-income setting with a high rate of burns, few specialists and few burn centres, yet a well-developed pre-hospital system. This paper describes the burn cases from a viewpoint of operational factors important to pre-hospital emergency medical services. A retrospective, cross-sectional study of administrative and patient records was conducted. Data were captured for all pre-hospital burn patients treated by public Emergency Medical Services over a continuous 12-month period. Data were captured separately at each site using a standardised data collection tool. Described categories included location (rural or urban), transport decision (transported or remained on scene), age (child or adult) and urgency (triage colour). EMS treated 1198 patients with confirmed burns representing 0.6% of the total EMS caseload; an additional 819 potential burn cases could not be confirmed. Of the confirmed cases, 625 (52.2%) were located outside the City of Cape Town and 1058 (88.3%) were transported to a medical facility. Patients from urban areas had longer mission times. Children accounted for 37.5% (n = 449) of all burns. The majority of transported patients that were triaged were yellow (n = 238, 41.6% rural and n = 182, 37.4% urban). Burns make up a small portion of the EMS caseload. More burns occurred in areas far from urban hospitals and burn centres. The majority of burn cases met the burn centre referral criteria.

  8. Stability studies of alkoxysilanes in aqueous media.

    Science.gov (United States)

    Kallos, G J; Tou, J C; Malczewski, R M; Boley, W F

    1991-07-01

    In order to correlate hydrolysis rates under physiological conditions to differences in toxicity of trimethoxysilane, tetramethoxysilane, and methyltrimethoxysilane, the rates of hydrolysis of these compounds were studied in deionized water, sodium phosphate buffer solution at pH 7.4, and 10% rat serum in sodium phosphate buffer at 37.4 degrees C. A strong surface effect was observed on the hydrolysis rates of tetramethoxysilane in different reactors in the following decreasing order: quartz greater than soft glass (I) greater than stainless steel greater than Teflon greater than soft glass (II). By using the soft glass (II) reactor as the reaction vessel for hydrolysis experiments, trimethoxysilane and tetramethoxysilane were found to be very unstable in 0.15 M sodium phosphate buffer (pH 7.4) and 10% rat serum (0.15 M sodium phosphate buffer, pH 7.4) with similar rates of hydrolysis at greater than 3.0 min-1 (t 1/2 less than 0.23 min). Under similar conditions, however, the rate of hydrolysis for tetramethoxysilane in deionized water was measured to be considerably slower (k = 0.022 min-1; t 1/2 = 32 min) than that of trimethoxysilane (k greater than 8.1 min-1, t 1/2 less than 0.09 min). However, the rates of hydrolysis for methyltrimethoxysilane in water, sodium phosphate buffer at pH 7.4, and 10% rat serum were measured to be 0.03 min-1 (t 1/2 = 24 min), 0.10 min-1 (t 1/2 = 6.7 min), and 0.08 min-1 (t 1/2 = 8.6 min), respectively.

  9. northern Sandveld, Western Cape, South Afric

    African Journals Online (AJOL)

    driniev

    The Department of Water Affairs and Forestry (DWAF) is currently carrying out detailed hydrogeological studies within the northern Sandveld area, Western Cape, South Africa. In addition, preliminary studies funded by DWAF, have also been carried out in the area assessing hydrological, ecological and botanical ...

  10. Comparative study of stability in different TCP/RED models

    International Nuclear Information System (INIS)

    Nga, J.H.C.; Iu, H.H.C.; Ling, S.H.; Lam, H.K.

    2008-01-01

    This paper studies the stability issue of the average queue length of a Transmission Control Protocol (TCP) model when interacting with Random Early Detection (RED). The model used for the study has shown period doubling bifurcation (PDB) and border collision bifurcation (BCB) in the average queue size at certain values of parameters when original RED is deployed. In this paper, we adopt a gentle version of RED and a newly derived RED algorithm into the model to study the improvement in stability of average queue size of the system

  11. The "Cape Times"'s Portrayal of School Violence

    Science.gov (United States)

    de Wet, Corene

    2016-01-01

    This study explores the "Cape Times"'s portrayal of school violence in the Western Cape (WC), South Africa, reporting on findings from a qualitative content analysis of 41 news articles retrieved from the SA Media database. The findings shed light on the victims and their victimisation, the perpetrators, as well as the context of the…

  12. Sugar preferences and digestion by Cape white-eyes, Zosterops ...

    African Journals Online (AJOL)

    In choice tests, birds preferred sucrose over glucose of equivalent weight, irrespective of concentration. It appears likely that the Cape white-eye has high levels of sucrase activity, although further study is needed to verify this. Key words: frugivory, sugar, fruit composition, digestion, preference, Cape white-eye, Zosterops ...

  13. Knowledge and attitudes in the rural Western Cape towards ...

    African Journals Online (AJOL)

    The study found that farm residents in the Western Cape are potentially exposed to pesticides through various environmental routes including water. This emphasises the need to monitor water for pesticides in the Western Cape, but in order to do this, human and laboratory resources and capacities to conduct routine ...

  14. An audit of povincial Gastroenterology services in the Western Cape ...

    African Journals Online (AJOL)

    The aim of this study was to audit the availability of GI facilities in the provincial sector, which provides care for the majority of people in the Western Cape. Method. All hospitals in the Western Cape providing endoscopy were evaluated by means of a hands-on audit, to identify available organisational infrastructure.

  15. Aspects of the digestion in the Cape porcupine | van Jaarsveld ...

    African Journals Online (AJOL)

    The digestive capabilities of the Cape porcupine (Hystrix africaeaustralis) were studied using captive and field animals. The stomach contents comprised 6,47% of the body mass and had a low pH (2,0).The Cape porcupine also has a long small intestine (670 em). The large stomach and small intestine form a very efficient ...

  16. The Cape Times's portrayal of school violence | de Wet | South ...

    African Journals Online (AJOL)

    This study explores the Cape Times's portrayal of school violence in the Western Cape (WC), South Africa, reporting on findings from a qualitative content analysis of 41 news articles retrieved from the SA Media database. The findings shed light on the victims and their victimisation, the perpetrators, as well as the context of ...

  17. The 1992 measles epidemic in Cape Town - a changing ...

    African Journals Online (AJOL)

    Over the last 6 years there has been a decline in the incidence of measles in Cape Town. However, during August 1992 an outbreak occurred, with cases reported at many schools in children presumably immunised. The objectives of this study were to characterise the epidemic in Cape Town and to determine possible ...

  18. Doping control container for urine stabilization: a pilot study.

    Science.gov (United States)

    Tsivou, Maria; Giannadaki, Evangelia; Hooghe, Fiona; Roels, Kris; Van Gansbeke, Wim; Garribba, Flaminia; Lyris, Emmanouil; Deventer, Koen; Mazzarino, Monica; Donati, Francesco; Georgakopoulos, Dimitrios G; Van Eenoo, Peter; Georgakopoulos, Costas G; de la Torre, Xavier; Botrè, Francesco

    2017-05-01

    Urine collection containers used in the doping control collection procedure do not provide a protective environment for urine, against degradation by microorganisms and proteolytic enzymes. An in-house chemical stabilization mixture was developed to tackle urine degradation problems encountered in human sport samples, in cases of microbial contamination or proteolytic activity. The mixture consists of antimicrobial substances and protease inhibitors for the simultaneous inactivation of a wide range of proteolytic enzymes. It has already been tested in lab-scale, as part of World Anti-Doping Agency's (WADA) funded research project, in terms of efficiency against microbial and proteolytic activity. The present work, funded also by WADA, is a follow-up study on the improvement of chemical stabilization mixture composition, application mode and limitation of interferences, using pilot urine collection containers, spray-coated in their internal surface with the chemical stabilization mixture. Urine in plastic stabilized collection containers have been gone through various incubation cycles to test for stabilization efficiency and analytical matrix interferences by three WADA accredited Laboratories (Athens, Ghent, and Rome). The spray-coated chemical stabilization mixture was tested against microorganism elimination and steroid glucuronide degradation, as well as enzymatic breakdown of proteins, such as intact hCG, recombinant erythropoietin and small peptides (GHRPs, ipamorelin), induced by proteolytic enzymes. Potential analytical interferences, observed in the presence of spray-coated chemical stabilization mixture, were recorded using routine screening procedures. The results of the current study support the application of the spray-coated plastic urine container, in the doping control collection procedure. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  19. The Humansdorp Cape Griffon Site

    African Journals Online (AJOL)

    ZeldaH

    Figure 1. The cliff north-west of the town of Humansdorp, Eastern Cape, South Africa, where a small group of Cape Griffons Gyps coprotheres roosted, and reportedly bred, until the end of the. 19 th century. The trees seen in the picture are all alien, invasive, black wattles Acacia mearnsii. (Photo: A Boshoff).

  20. Self-reported chemicals exposure, beliefs about disease causation, and risk of breast cancer in the Cape Cod Breast Cancer and Environment Study: a case-control study

    Science.gov (United States)

    2010-01-01

    Background Household cleaning and pesticide products may contribute to breast cancer because many contain endocrine disrupting chemicals or mammary gland carcinogens. This population-based case-control study investigated whether use of household cleaners and pesticides increases breast cancer risk. Methods Participants were 787 Cape Cod, Massachusetts, women diagnosed with breast cancer between 1988 and 1995 and 721 controls. Telephone interviews asked about product use, beliefs about breast cancer etiology, and established and suspected breast cancer risk factors. To evaluate potential recall bias, we stratified product-use odds ratios by beliefs about whether chemicals and pollutants contribute to breast cancer; we compared these results with odds ratios for family history (which are less subject to recall bias) stratified by beliefs about heredity. Results Breast cancer risk increased two-fold in the highest compared with lowest quartile of self-reported combined cleaning product use (Adjusted OR = 2.1, 95% CI: 1.4, 3.3) and combined air freshener use (Adjusted OR = 1.9, 95% CI: 1.2, 3.0). Little association was observed with pesticide use. In stratified analyses, cleaning products odds ratios were more elevated among participants who believed pollutants contribute "a lot" to breast cancer and moved towards the null among the other participants. In comparison, the odds ratio for breast cancer and family history was markedly higher among women who believed that heredity contributes "a lot" (OR = 2.6, 95% CI: 1.9, 3.6) and not elevated among others (OR = 0.7, 95% CI: 0.5, 1.1). Conclusions Results of this study suggest that cleaning product use contributes to increased breast cancer risk. However, results also highlight the difficulty of distinguishing in retrospective self-report studies between valid associations and the influence of recall bias. Recall bias may influence higher odds ratios for product use among participants who believed that chemicals and

  1. Self-reported chemicals exposure, beliefs about disease causation, and risk of breast cancer in the Cape Cod Breast Cancer and Environment Study: a case-control study.

    Science.gov (United States)

    Zota, Ami R; Aschengrau, Ann; Rudel, Ruthann A; Brody, Julia Green

    2010-07-20

    Household cleaning and pesticide products may contribute to breast cancer because many contain endocrine disrupting chemicals or mammary gland carcinogens. This population-based case-control study investigated whether use of household cleaners and pesticides increases breast cancer risk. Participants were 787 Cape Cod, Massachusetts, women diagnosed with breast cancer between 1988 and 1995 and 721 controls. Telephone interviews asked about product use, beliefs about breast cancer etiology, and established and suspected breast cancer risk factors. To evaluate potential recall bias, we stratified product-use odds ratios by beliefs about whether chemicals and pollutants contribute to breast cancer; we compared these results with odds ratios for family history (which are less subject to recall bias) stratified by beliefs about heredity. Breast cancer risk increased two-fold in the highest compared with lowest quartile of self-reported combined cleaning product use (Adjusted OR = 2.1, 95% CI: 1.4, 3.3) and combined air freshener use (Adjusted OR = 1.9, 95% CI: 1.2, 3.0). Little association was observed with pesticide use. In stratified analyses, cleaning products odds ratios were more elevated among participants who believed pollutants contribute "a lot" to breast cancer and moved towards the null among the other participants. In comparison, the odds ratio for breast cancer and family history was markedly higher among women who believed that heredity contributes "a lot" (OR = 2.6, 95% CI: 1.9, 3.6) and not elevated among others (OR = 0.7, 95% CI: 0.5, 1.1). Results of this study suggest that cleaning product use contributes to increased breast cancer risk. However, results also highlight the difficulty of distinguishing in retrospective self-report studies between valid associations and the influence of recall bias. Recall bias may influence higher odds ratios for product use among participants who believed that chemicals and pollutants contribute to breast cancer

  2. Self-reported chemicals exposure, beliefs about disease causation, and risk of breast cancer in the Cape Cod Breast Cancer and Environment Study: a case-control study

    Directory of Open Access Journals (Sweden)

    Rudel Ruthann A

    2010-07-01

    Full Text Available Abstract Background Household cleaning and pesticide products may contribute to breast cancer because many contain endocrine disrupting chemicals or mammary gland carcinogens. This population-based case-control study investigated whether use of household cleaners and pesticides increases breast cancer risk. Methods Participants were 787 Cape Cod, Massachusetts, women diagnosed with breast cancer between 1988 and 1995 and 721 controls. Telephone interviews asked about product use, beliefs about breast cancer etiology, and established and suspected breast cancer risk factors. To evaluate potential recall bias, we stratified product-use odds ratios by beliefs about whether chemicals and pollutants contribute to breast cancer; we compared these results with odds ratios for family history (which are less subject to recall bias stratified by beliefs about heredity. Results Breast cancer risk increased two-fold in the highest compared with lowest quartile of self-reported combined cleaning product use (Adjusted OR = 2.1, 95% CI: 1.4, 3.3 and combined air freshener use (Adjusted OR = 1.9, 95% CI: 1.2, 3.0. Little association was observed with pesticide use. In stratified analyses, cleaning products odds ratios were more elevated among participants who believed pollutants contribute "a lot" to breast cancer and moved towards the null among the other participants. In comparison, the odds ratio for breast cancer and family history was markedly higher among women who believed that heredity contributes "a lot" (OR = 2.6, 95% CI: 1.9, 3.6 and not elevated among others (OR = 0.7, 95% CI: 0.5, 1.1. Conclusions Results of this study suggest that cleaning product use contributes to increased breast cancer risk. However, results also highlight the difficulty of distinguishing in retrospective self-report studies between valid associations and the influence of recall bias. Recall bias may influence higher odds ratios for product use among participants who believed

  3. Importance of stability study of continuous systems for ethanol production.

    Science.gov (United States)

    Paz Astudillo, Isabel Cristina; Cardona Alzate, Carlos Ariel

    2011-01-10

    Fuel ethanol industry presents different problems during bioreactors operation. One of them is the unexpected variation in the output ethanol concentration from the bioreactor or a drastic fall in the productivity. In this paper, a compilation of concepts and relevant results of several experimental and theoretical studies about dynamic behavior of fermentation systems for bioethanol production with Saccharomyces cerevisiae and Zymomonas mobilis is done with the purpose of understanding the stability phenomena that could affect the productivity of industries producing fuel ethanol. It is shown that the design of high scale biochemical processes for fuel ethanol production must be done based on stability studies. © 2010 Elsevier B.V. All rights reserved.

  4. 33 CFR 80.525 - Cape Lookout, NC to Cape Fear, NC.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Cape Lookout, NC to Cape Fear, NC... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Fifth District § 80.525 Cape Lookout, NC to Cape Fear... southeast side of the Inlet. (g) Except as provided elsewhere in this section from Cape Lookout to Cape Fear...

  5. Stability studies of colloidal silica dispersions in binary solvent mixtures

    CERN Document Server

    Bean, K H

    1997-01-01

    A series of monodispersed colloidal silica dispersions, of varying radii, has been prepared. These particles are hydrophilic in nature due to the presence of surface silanol groups. Some of the particles have been rendered hydrophobic by terminally grafting n-alkyl (C sub 1 sub 8) chains to the surface. The stability of dispersions of these various particles has been studied in binary mixtures of liquids, namely (i) ethanol and cyclohexane, and (ii) benzene and n-heptane. The ethanol - cyclohexane systems have been studied using a variety of techniques. Adsorption excess isotherms have been established and electrophoretic mobility measurements have been made. The predicted stability of the dispersions from D.V.L.O. calculations is compared to the observed stability. The hydrophilic silica particles behave as predicted by the calculations, with the zeta potential decreasing and the van der Waals attraction increasing with increasing cyclohexane concentration. The hydrophobic particles behave differently than e...

  6. [Formulation and stability of suspensions for preclinical study].

    Science.gov (United States)

    Burgalassi, S; Perini, G; Giannaccini, B; Saettone, M F; Lodi, A

    1997-11-01

    In preclinical studies, poorly soluble drugs are usually administered orally to experimental animals as suspensions. The present study was aimed at providing data allowing predictive estimations of the stability of such suspensions. To this purpose aqueous suspensions of three drugs (griseofulvin, ibuprofen and indomethacin) were prepared at different concentrations using four different suspending agents: sodium carboxymethylcellulose (CMC), microcrystalline cellulose/carboxymethylcellulose (MC/CMC), hydroxypropylmethylcellulose (HPMC) and jota carragenaan (CJ). The physical and physico-chemical characteristics of the drugs, the rheological properties of the suspending media and of the corresponding drug suspensions, and the physical and chemical stability of the suspensions was then evaluated. The type of suspending agent, rather than the physical characteristics of the drug, appeared to exert the main influence on the physical stability of suspensions. The most stable formulations were produced by suspending agents with low-temperature gelation characteristics (CJ) or with thixotropic flux (MC/CMC).

  7. neonatal bacterial meningitis in Cape Town children

    African Journals Online (AJOL)

    neonatal bacterial meningitis in Cape Town children. Bacterial meningitis is a major cause of childhood morbidity and mortality in South Africa. However, comprehensive regional or national epidemiological data, essential for rational public health interventions, are lacking. The purpose of this 1-year prospective study, from.

  8. Tuberculosis drug resistance in the Western Cape

    African Journals Online (AJOL)

    Objectives. Drug resistance is a serious problem in the treatment of tuberculosis and a threat to successful tuberculosis control programmes. Local health workers have expressed concern that the increasing tuberculosis epidemic in the Western Cape is partly attributable to drug resistance. The aim of this study was to ...

  9. The Cape Times's portrayal of school violence

    Directory of Open Access Journals (Sweden)

    Corene de Wet

    2016-05-01

    Full Text Available This study explores the Cape Times's portrayal of school violence in the Western Cape (WC, South Africa, reporting on findings from a qualitative content analysis of 41 news articles retrieved from the SA Media database. The findings shed light on the victims and their victimisation, the perpetrators, as well as the context of the violence, identifying gangsterism, as well as school administrative and community factors as the reasons for violence in WC schools. It is argued that school violence and gangsterism are inextricably linked to the Cape Flats in particular, and that the interaction of forms of inequality and oppression such as racism, class privilege and gender oppression are structural root causes for school violence in this area of the WC. The study highlights the negative consequences of school violence on teaching and learning and on the economy. It is concluded that even if the Cape Times paints an exaggerated and atypical picture of violence in the gang-riddled parts of the WC, the detrimental effects thereof on the regions cannot be denied. The study therefore recommends a holistic approach to addressing the structural root causes of school violence where it takes place in the WC.

  10. Thermodynamic stability studies of Ce-Sb compounds with Fe

    Science.gov (United States)

    Xie, Yi; Zhang, Jinsuo; Benson, Michael T.; Mariani, Robert D.

    2018-02-01

    Lanthanide fission products can migrate to the fuel periphery and react with cladding, causing fuel-cladding chemical interaction (FCCI). Adding a fuel additive dopant, such as Sb, can bind lanthanide, such as Ce, into metallic compounds and thus prevent migration. The present study focuses on the thermodynamic stability of Ce-Sb compounds when in contact with the major cladding constituent Fe by conducting diffusion couple tests. Ce-Sb compounds have shown high thermodynamic stability as they did not react with Fe. When Fe-Sb compounds contacted with Ce, Sb was separated out of Fe-Sb compounds and formed the more stable Ce-Sb compounds.

  11. Study the Stability of a Wastewater Treatment Unit using LABVIEW

    Directory of Open Access Journals (Sweden)

    Ghainm M. Alwan

    2013-05-01

    Full Text Available This study was devoted to limit the stability conditions of the wastewater treatment unit.       LABVIEW was a powerful and versatile graphical programming language in automation control and date acquisition of the system. The on-line show that accurate and stable control responses were obtained in the present work. The actual phase plane proved to a better technique to limit the regions of the non-linear system stability compared to other theoretical techniques. Limit cycle did not appear in the present system. 

  12. Health Systems Readiness to Manage the Hypertension Epidemic in Primary Health Care Facilities in the Western Cape, South Africa: A Study Protocol.

    Science.gov (United States)

    Deuboué Tchialeu, Rodrigue Innocent; Yaya, Sanni; Labonté, Ronald

    2016-02-29

    Developing countries are undergoing a process of epidemiological transition from infectious to noncommunicable diseases, described by the United Nations Secretary General Ban Ki-Moon as ''a public health emergency in slow motion." One of the most prevalent in sub-Saharan Africa is hypertension, which is a complex chronic condition often referred to as a "silent killer" and key contributor to the development of cardiovascular and cerebrovascular diseases. Hypertensive patients in this setting are estimated to increase from 74.7 million in 2008 to 125.5 million in 2025, a 68% increase. However, there is an important gap between emerging high-level policies and recommendations, and the near-absence of practical guidance and experience delivering long-term medical care for noncommunicable diseases within resource-limited health systems. To address this gap, our study will consist of field investigations to determine the minimum health systems requirements to ensure successful delivery of antihypertensive medications when scaling-up interventions to control the hypertension epidemic. A cross-sectional analytic study will be conducted in the Western Cape using a mixed-method approach with two semistructured interview guides. The first will be for health professionals involved in the care of hypertensive patients within at least 6 community health centers (3 urban and 3 rural) to understand the challenges associated with their care. The second will be to map and assess the current supply chain management system of antihypertensive medications by interviewing key informants at different levels of the processes. Finally, modeling and simulation tools will be used to understand how to estimate minimum numbers of health workers required at each supply chain interval to ensure successful delivery of medications when scaling-up interventions. Funding for the study was secured through a Doctoral Research Award in October 2014 from the International Development Research Centre

  13. A summary of studies of particle stability at RHIC

    International Nuclear Information System (INIS)

    Parzen, G.

    1992-01-01

    This paper summarizes some studies of particle stability done at RHIC. The topics reported on include: Long-term tracking and the dynamic aperture; linear coupling effects and their correction; and tune spreads in the beam due to field multipoles in the magnets and their correction

  14. Stability and quench development study in small HTSC magnet

    NARCIS (Netherlands)

    Ilyin, Y.; Vysotski, V.S.; Kiss, T.; Takeo, M.; Okamoto, H.; Irie, F.

    2001-01-01

    Stability and quench development in a HTSC magnet have been experimentally studied with the transport current in the magnet being below or above the “thermal quench current” level. The magnet was tested at both cryocooler cooling and liquid nitrogen cooling, with and without background magnetic

  15. Studies on storage stability of radurised Indian Mackerel (Rastrelliger Kanagurta)

    International Nuclear Information System (INIS)

    Ghadi, S.V.; Alur, M.D.; Venugopal, V.; Doke, S.N.; Ghosh, S.K.; Lewis, N.F.; Nadkarni, G.B.

    1977-01-01

    The present report describes the storage stability of mackerel maintained at various temperatures (0deg-20degC). The investigations include radiation-induced shifts in microflora of mackerel during storage, and time-temperature-tolerance (TTT) studies with the unirradiated and radurized mackerel. (author)

  16. A study on structural stability of bismuth titanate with lanthanum ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 40; Issue 3. A study on structural stability of bismuth titanate with lanthanum ... In addition, the enlarged region of Bi 4f, Bi 4d, Ti 2p, La 3d and O 1s of doping sample was clearly seen after deconvolution. Based on binding energy position, it can be unambiguously stated ...

  17. Comparative study of the influence of cement and lime stabilization ...

    African Journals Online (AJOL)

    Comparative study of the influence of cement and lime stabilization on geotechnical properties of lateritic soil derived from pegmatite in Ago-Iwoye area, southwestern Nigeria. MO Oloruntola, GO Adeyemi, OC Oduneye. Abstract. No Abstract. Journal of Mining and Geology Vol. 44 (1) 2008: pp. 95-105. Full Text:.

  18. [Study on composite stabilization of arsenic (As) contaminated soil].

    Science.gov (United States)

    Wang, Hao; Pan, Li-xiang; Zhang, Xiang-yu; Li, Meng; Song, Bao-hua

    2013-09-01

    Since the contaminated soil may contain various kinds of heavy metals, use of single chemical reagent leads to poor remediation and high cost. In this study, soil containing As, Zn, Cd was sampled, and different reagents were selected to carry out the rapid stabilization of contaminated soil. The TCLP (toxicity characteristic leaching procedure) was used to evaluate the leachate toxicity of heavy metals and the results indicated that calcium-containing, sulphur-containing and iron-containing reagents had good performance in reducing the metal mobility. The stabilization efficiency of the six reagents tested ranked in the order of CaO > Na2S > organic sulfur > Chitosan > FeSO4 > (C2H5)2NCS2Na. Two types of reagents (six reagents) were combined based on the target properties of different reagents and the stabilization efficiency was evaluated and analyzed. The results indicated that the composite reagents had higher stabilization efficiency: the efficiency of 3% FeSO4 + 5% CaO was 81.7%, 97.2% and 68.2% for As, Cd and Zn, respectively, and the efficiency of 3% CaO + 5% organic sulfur was 76.6%, 95.7% and 93.8% for these three metals, respectively. Speciation analysis was carried out in this study and the results suggested that it was the change of metals from the exchangeable state to the reduction (for inorganic reagent) or oxidation state (for organic reagent) that caused the soil stabilization and the degree of change determined the stabilization efficiency.

  19. RESULTS OF COMPREHENSIVE STUDIES OF THE UNDERGROUND HYDROSPHERE WITHIN THE WESTERN SHOULDER OF THE BAIKAL RIFT (AS EXEMPLIFIED BY THE BAYANDAI – KRESTOVSKY CAPE SITE

    Directory of Open Access Journals (Sweden)

    Konstantin Zh. Seminsky

    2011-01-01

    Full Text Available The subject of comprehensive studies is the underground hydrosphere of the upper crust of the western shoulder of the Baikal rift, being characterized by high tectonic activity in the recent stage of tectogenesis. The studies were focused on the Bayandai – Krestovsky Cape site, considering it as a benchmark for the territory of the Western Pribiakalie (Fig. 1. The available hydrogeological survey database is used to study underground waters circulating at depth of several kilometers. Analyses of deeper waters are conducted on the basis of geophysical data. According to results of initial geological and geophysical studies [Семинский и др., 2010], the crust at the junction of the Siberian crater and the SayanBaikal folded belt is characterized by a hierarchic zoneblock structure (Fig. 2. Regardless of the scale of studies, the territory under study can be divided into sections of two types, that alternate from NW to SE and represent wide highly destructed zones and relatively monolithic blocks of the crust. The Obruchev fault system is distinguished as the main interblock zone (the 2nd hierarchic level in the study area. It represents the 50 km long NW shoulder of the Baikal rift (the1st hierarchic level and includes the Morskaya, Primorskaya and Prikhrebtovaya interplate zones (the 3rd hierarchic level. These zones are traced from depth of dozens of kilometers; at the surface, they are represented by fault structures of the highest hierarchic levels.Specific features of the current zoneblock divisibility of the crust serve as the structural basis for interpreting the materials obtained by hydrogeological studies conducted on the Bayandai – Krestovsky Cape site to research the distribution, mineralization and macrocomponent compositions of waters which represent the subsurface part of the underground lithosphere in the study area. The research is based on analyses of the underground water samples from 46 observation points

  20. Influences of social network sites on the occupational performance of adolescents in a secondary school in Cape Town, South Africa: a phenomenological study.

    Science.gov (United States)

    Mthembu, Thuli G; Beets, Charmaine; Davids, Gafeedha; Malyon, Kelly; Pekeur, Marchelle; Rabinowitz, Avital

    2014-06-01

    The habit of using social networking sites among adolescents has grown exponentially; there is little accompanying research to understand the influences on adolescents' occupational performance with this technology. The majority of adolescents are engaging in social network as part of their daily routines. Occupational performance is the act of doing and accomplishing a selected occupation that results from the dynamic transaction among the person, the environment and the occupation components. This study aimed to explore the influences of social networking on occupational performance of adolescents in a high school in Western Cape Province, South Africa. A phenomenological approach was used. Adolescents aged 13-17 years in a high school were purposively recruited for the study. Semi-structured interviews were conducted with four participants (two adolescents and two teachers) and two focus groups were undertaken with adolescents, analysed using thematic analysis. Four major themes emerged: 'It's a good way to keep in touch', 'It's part of me and it's not a bad thing', 'There is a time and place for it' and 'There's an urgency to be on the phone'. This study highlighted that social networking sites play a major role in the social life of adolescents, though it can result in occupational imbalance on their occupational performance. Furthermore, this study contributes to the knowledge of occupational therapists who work with adolescents in communities and health promoting school settings. Thus, collaboration between teachers, parents and occupational therapists can help to develop adolescents' time management and learning skills. © 2013 Occupational Therapy Australia.

  1. Stability studies of colloidal silica dispersions in binary solvent mixtures

    International Nuclear Information System (INIS)

    Bean, Keith Howard

    1997-01-01

    A series of monodispersed colloidal silica dispersions, of varying radii, has been prepared. These particles are hydrophilic in nature due to the presence of surface silanol groups. Some of the particles have been rendered hydrophobic by terminally grafting n-alkyl (C 18 ) chains to the surface. The stability of dispersions of these various particles has been studied in binary mixtures of liquids, namely (i) ethanol and cyclohexane, and (ii) benzene and n-heptane. The ethanol - cyclohexane systems have been studied using a variety of techniques. Adsorption excess isotherms have been established and electrophoretic mobility measurements have been made. The predicted stability of the dispersions from D.V.L.O. calculations is compared to the observed stability. The hydrophilic silica particles behave as predicted by the calculations, with the zeta potential decreasing and the van der Waals attraction increasing with increasing cyclohexane concentration. The hydrophobic particles behave differently than expected, and the stability as a function of solvent mixture composition does not show a uniform trend. The effect of varying the coverage of C 18 chains on the surface and the effect of trace water in the systems has also been investigated. Organophilic silica dispersions in benzene - n-heptane solvent mixtures show weak aggregation and phase separation into a diffuse 'gas-like' phase and a more concentrated 'liquid-like' phase, analogous to molecular condensation processes. Calculations of the van der Waals potential as a function of solvent mixture composition show good agreement with the observed stability. Determination of the number of particles in each phase at equilibrium allows the energy of flocculation to be determined using a simple thermodynamic relationship. Finally, the addition of an AB block copolymer to organophilic silica particles in benzene n-heptane solvent mixtures has been shown to have a marked effect on the dispersion stability. This stability

  2. Solidifications/stabilization treatability study of a mixed waste sludge

    International Nuclear Information System (INIS)

    Spence, R.D.; Stine, E.F.

    1996-01-01

    The Department of Energy Oak Ridge Operations Office signed a Federal Facility Compliance Agreement with the US Environmental Protection Agency Region IV regarding mixed wastes from the Oak Ridge Reservation (ORR) subject to the land disposal restriction provisions of the Resource Conservation and Recovery Act (RCRA). This agreement required treatability studies of solidification/stabilization (S/S) on mixed wastes from the ORR. This paper reports the results of the cementitious S/S studies conducted on a waste water treatment sludge generated from biodenitrification and heavy metals precipitation. For the cementitious waste forms, the additives tested were Portland cement, ground granulated blast furnace slag, Class F fly ash, and perlite. The properties measured on the treated waste were density, free-standing liquid, unconfined compressive strength, and TCLP performance. Spiking up to 10,000, 10,000, and 4,400 mg/kg of nickel, lead, and cadmium, respectively, was conducted to test waste composition variability and the stabilization limitations of the binding agents. The results indicated that nickel, lead and cadmium were stabilized fairly well in the high pH hydroxide-carbonate- ''bug bones'' sludge, but also clearly confirmed the established stabilization potential of cementitious S/S for these RCRA metals

  3. Potential capabilities at LAMPF to study nuclei far from stability

    International Nuclear Information System (INIS)

    Talbert, W.L.; Bunker, M.E.

    1985-01-01

    Feasibility studies have shown that a He-jet activity transport line, with a target chamber placed in the LAMPF main beam line, will provide access to short-lived isotopes of a number of elements that cannot be extracted efficiently for study at any other type of on-line facility. The He-jet technique requires targets thin enough to allow a large fraction of the reaction products to recoil out of the target foils; hence, a very intense incident beam current, such as that uniquely available at LAMPF, is needed to produce yields of individual radioisotopes sufficient for detailed nuclear studies. We present the results of feasibility experiments on He-jet transport efficiency and timing. We also present estimates on availability of nuclei far from stability from both fission and spallation processes. Areas of interest for study of nuclear properties far from stability will be outlined. 17 refs

  4. Sociality and the telencephalic distribution of corticotrophin-releasing factor, urocortin 3, and binding sites for CRF type 1 and type 2 receptors: A comparative study of eusocial naked mole-rats and solitary Cape mole-rats.

    Science.gov (United States)

    Coen, Clive W; Kalamatianos, Theodosis; Oosthuizen, Maria K; Poorun, Ravi; Faulkes, Christopher G; Bennett, Nigel C

    2015-11-01

    Various aspects of social behavior are influenced by the highly conserved corticotrophin-releasing factor (CRF) family of peptides and receptors in the mammalian telencephalon. This study has mapped and compared the telencephalic distribution of the CRF receptors, CRF1 and CRF2 , and two of their ligands, CRF and urocortin 3, respectively, in African mole-rat species with diametrically opposed social behavior. Naked mole-rats live in large eusocial colonies that are characterized by exceptional levels of social cohesion, tolerance, and cooperation in burrowing, foraging, defense, and alloparental care for the offspring of the single reproductive female. Cape mole-rats are solitary; they tolerate conspecifics only fleetingly during the breeding season. The telencephalic sites at which the level of CRF1 binding in naked mole-rats exceeds that in Cape mole-rats include the basolateral amygdaloid nucleus, hippocampal CA3 subfield, and dentate gyrus; in contrast, the level is greater in Cape mole-rats in the shell of the nucleus accumbens and medial habenular nucleus. For CRF2 binding, the sites with a greater level in naked mole-rats include the basolateral amygdaloid nucleus and dentate gyrus, but the septohippocampal nucleus, lateral septal nuclei, amygdalostriatal transition area, bed nucleus of the stria terminalis, and medial habenular nucleus display a greater level in Cape mole-rats. The results are discussed with reference to neuroanatomical and behavioral studies of various species, including monogamous and promiscuous voles. By analogy with findings in those species, we speculate that the abundance of CRF1 binding in the nucleus accumbens of Cape mole-rats reflects their lack of affiliative behavior. © 2015 Wiley Periodicals, Inc.

  5. Water and Regional Stability: The Nile a Case Study

    Science.gov (United States)

    2011-03-24

    Basin-Wide Study Final Report ( Dar es Salaam , Tanzania, May 2008), 2-1, 2-2. 30 Global Water Partnership Toolbox IWRM page, http...St ra te gy R es ea rc h Pr oj ec t WATER AND REGIONAL STABILITY: THE NILE A CASE STUDY BY LIEUTENANT COLONEL JOHN C. CURWEN United...in her remarks to Congress , eloquently described many of the reasons why the United States views water as strategically important1. The 2010 report

  6. A study on occlusal stability in shortened dental arches.

    Science.gov (United States)

    Sarita, Paulo T N; Kreulen, Cees M; Witter, Dick J; van't Hof, Martin; Creugers, Nico H J

    2003-01-01

    The aim of this study was to verify the hypothesis that shortened dental arches constitute a risk to occlusal stability. Using cluster samples, 725 subjects with shortened dental arches comprising intact anterior regions and zero to eight occluding pairs of posterior teeth and 125 subjects with complete dental arches were selected. Subjects with shortened dental arches were classified into eight categories according to arch length and symmetry. Parameters for occlusal stability were interdental spacing, occlusal tooth wear, occlusal contact of incisors in intercuspal position, and vertical and horizontal overlap. Additionally, tooth mobility and overeruption of unopposed teeth were assessed. Influence of independent variables (dental arch category, age, gender, and residence) on the parameters for occlusal stability was assessed by one-way ANOVA and Tukey's multiple range tests. Extreme shortened dental arches (zero to two pairs of occluding premolars) had significantly more interdental spacing, occlusal contact of incisors, and vertical overlap compared to complete dental arches. Occlusal wear and prevalence of mobile teeth were highest in these categories. The category with three to four occluding premolars had significantly more interdental spacing and, for the older age group, more anterior teeth in occlusal contact compared to complete dental arches. Age was consistently associated with increased changes in occlusal integrity. Signs of increased risk to occlusal stability seemed to occur in extreme shortened dental arches, whereas no such evidence was found for intermediate categories of shortened dental arches.

  7. The preformulation stability studies of a proline prodrug of methotrexate.

    Science.gov (United States)

    Stephenson, Ann; Wu, Zhiqian; Yuan, Xudong

    2012-07-01

    In order to reduce toxicity of methotrexate and improve bioavailability, permeability, and explore other delivery routes, a proline prodrug of methotrexate was synthesized and preformulation stability studies were conducted under accelerated conditions to assess compound liability and possible conversion to the parent drug. Forced degradation studies showed that the prodrug will degrade in the presence of water, acid, and heat (70 °C), generating the parent compound methotrexate. It was also found that this conversion is temperature dependent. In addition, the prodrug is extremely light and oxidative labile. Therefore, future formulation studies should be light protected and stabilized by a suitable antioxidant. It was also found that the prodrug is stable in the HPLC diluent, consisting of water and acetonitrile; stored bench-top and protected from light for up to two weeks.

  8. An Approach to Developing a Prediction Model of Fertility Intent among HIV-Positive Women and Men in Cape Town, South Africa: A Case Study

    Science.gov (United States)

    Bai, Dan; Leu, Cheng-Shiun; Mantell, Joanne E.; Exner, Theresa M.; Cooper, Diane; Hoffman, Susie; Kelvin, Elizabeth A.; Myer, Landon; Constant, Debbie; Moodley, Jennifer

    2016-01-01

    As a ‘case-study’ to demonstrate an approach to establishing a fertility-intent prediction model, we used data collected from recently diagnosed HIV-positive women (N=69) and men (N=55) who reported inconsistent condom use and were enrolled in a sexual and reproductive health intervention in public sector HIV care clinics in Cape Town, South Africa. Three theoretically-driven prediction models showed reasonable sensitivity (0.70 to 1.00), specificity (0.66 to 0.94), and area under the receiver operating characteristic curve (0.79 to 0.89) for predicting fertility intent at the six-month visit. A k-fold cross-validation approach was employed to reduce bias due to over-fitting of data in estimating sensitivity, specificity, and area under the curve. We discuss how the methods presented might be used in future studies to develop a clinical screening tool to identify HIV-positive individuals likely to have future fertility intent and who could therefore benefit from sexual and reproductive health counseling around fertility options. PMID:27294266

  9. I am not "umqwayito'': a qualitative study of peer pressure and sexual risk behaviour among young adolescents in Cape Town, South Africa.

    Science.gov (United States)

    Selikow, Terry-Ann; Ahmed, Nazeema; Flisher, Alan J; Mathews, Catherine; Mukoma, Wanjiru

    2009-06-01

    Young people in South Africa are susceptible to HIV infection. They are vulnerable to peer pressure to have sex, but little is known about how peer pressure operates. The aim of the study was to understand how negative peer pressure increases high risk sexual behaviour among young adolescents in Cape Town, South Africa. Qualitative research methods were used. Eight focus groups were conducted with young people between the ages of 13 and 14 years. Peer pressure among both boys and girls undermines healthy social norms and HIV prevention messages to abstain, be faithful, use a condom and delay sexual debut. HIV prevention projects need to engage with peer pressure with the aim of changing harmful social norms into healthy norms. Increased communication with adults about sex is one way to decrease the impact of negative peer pressure. Peer education is a further mechanism by which trained peers can role model healthy social norms and challenge a peer culture that promotes high risk sexual behaviour. Successful HIV prevention interventions need to engage with the disconnect between educational messages and social messages and to exploit the gaps between awareness, decision making, norms, intentions and actions as spaces for positive interventions.

  10. CAPE TOWN'S TIME-GUNS

    African Journals Online (AJOL)

    Although a great many articles have been writ- ten on the subject of Cape Town's noon gun (the. official terminology is 'time-gun') most of the writ- ers have not had access to the Lion Battery Fort. Record Book and the existance of more than one. Cape Town time-gun has only recently been re- corded. By 1807 a noon gun ...

  11. Stability studies on florfenicol using developed derivative spectrophotometric methods.

    Science.gov (United States)

    Elimam, M M; Shantier, S W; Gadkariem, E A; Mohamed, M A; Osman, Z

    2017-01-01

    This study aims to investigate the stability of florfenicol using previously developed derivative spectrophotometric methods (D 1 and D 2 ). The studied stability-indicating pararmeters included alkali (NaOH, 1M), acid (HCl, 1M), pH changes (buffer pH 2.2-11), temperature (80°C and 100°C at pH 10) and light. A constructed pH profile for the drug degradation rate revealed a significant effect of pH on the drug stability between pH ranges 8 and 11. The obtained profile indicated first order dependence of K obs on [OH - ]. Arrhenius plot at pH 10 was found linear at temperatures 80°C and 100°C with estimated activation energy of 19.35kcal/mol. The calculated rate constant (K obs ), t ½ and t 90 at 25°C were found to be 1.8×10 -3 h, 385h and 58.3h, respectively. The photostability of florfenicol was also studied by exposing the drug solution to direct sunlight during mid-day time. The obtained results reflected the instability of florfenicol under the study conditions. Copyright © 2016 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.

  12. Genotype x environment interactions and yield stability of stress ...

    African Journals Online (AJOL)

    Genotype x environment interactions are inherent in multilocational trials and complicate identification of superior genotypes. The aim of the study was to determine yield performance and stability of 13 maize genotypes in five locations of the Eastern Cape province, South Africa. The genotypes assessed were: ZM305, ...

  13. Polyaniline Conducting Electroactive Polymers Thermal and Environmental Stability Studies

    OpenAIRE

    Ansari, Reza; Keivani, M. B.

    2006-01-01

    In the current studies, polyaniline (PANi) was prepared both chemical and electrochemically in the presence of different bronsted acids from aqueous solutions. The effect of thermal treatment on electrical conductivity, and thermal stability of the PANi conducting polymers were investigated using 4-point probe and TGA techniques respectively. It was found that polymer prepared by CV method is more thermally stable than those prepared by the other electrochemical techniques. In this paper we h...

  14. Characterization and stability studies of emulsion systems containing pumice

    Directory of Open Access Journals (Sweden)

    Marilene Estanqueiro

    2014-04-01

    Full Text Available Emulsions are the most common form of skin care products. However, these systems may exhibit some instability. Therefore, when developing emulsions for topical application it is interesting to verify whether they have suitable physical and mechanical characteristics and further assess their stability. The aim of this work was to study the stability of emulsion systems, which varied in the proportion of the emulsifying agent cetearyl alcohol (and sodium lauryl sulfate (and sodium cetearyl sulfate (LSX, the nature of the oily phase (decyl oleate, cyclomethicone or dimethicone and the presence or absence of pumice (5% w/w. While maintaining the samples at room temperature, rheology studies, texture analysis and microscopic observation of formulations with and without pumice were performed. Samples were also submitted to an accelerated stability study by centrifugation and to a thermal stress test. Through the testing, it was found that the amount of emulsifying agent affects the consistency and textural properties such as firmness and adhesiveness. So, formulations containing LSX (5% w/w and decyl oleate or dimethicone as oily phase had a better consistency and remained stable with time, so exhibited the best features to be used for skin care products.

  15. Study of the Alvarez linac stabilized with post-couplers

    International Nuclear Information System (INIS)

    Machida, Shinji.

    1985-11-01

    A model of Alvarez linac equipped with post-couplers was constructed. The field distribution and the resonant frequency of the accelerating mode were measured to study its properties against perturbations such as manufacturing errors of the tank. The experimental results were compared with an analysis using equivalent circuits. The mechanism of the stabilization was confirmed by the analysis and the following remarkable information about this structure were obtained: Post-couplers have an effect to distort the field distribution as well as to stabilize it depending upon the length of post-couplers inserted into the tank. Furthermore, the role of tabs which are used to tilt the field distribution and the difference between a post-coupled structure and a multi-stem structure are investigated with the analysis of equivalent circuits. (author)

  16. [Genetic stability study on autotetraploid plant of Dioscorea zingiberensis].

    Science.gov (United States)

    Huang, He-Ping; Gao, Shan-Lin; Huang, Lu-Qi; Wang, Dian-Lei; Huang, Peng

    2014-03-01

    To study the genetic stability of autotetraploid plant of Dioscorea zingiberensis. The chromosome of root-tip was determined by photomicroscope, and the agronomic characters were observed in the period of stable growth. The protein content was determined and the experiment of protein polyacrylamide gel electrophoresis was carried out. Furthemore, the diosgenin content was determined and compared. The chromosome number of autotetraploid plantlet was 2n = 4x = 40. The agronomic characters showed typical autotetraploid characteristics. The contents of diosgenin and protein of autotetraploid were higher than that of the diploid. The protein electrophoresis bands of all the lines were similar. The experiment confirmed that the autotetraploid plant of Dioscorea zingiberensis, which was artificially induced, had good genetic stability. It lays the foundation for the polyploid breeding to develop superior varieties of Dioscorea zingiberensis.

  17. Orthodontic treatment stability predictors: A retrospective longitudinal study.

    Science.gov (United States)

    de Bernabé, Paloma González-Gil; Montiel-Company, José María; Paredes-Gallardo, Vanessa; Gandía-Franco, Jose Luis; Bellot-Arcís, Carlos

    2017-03-01

    To examine medium- to long-term orthodontic treatment stability and its possible association with certain variables. In a retrospective longitudinal study of 70 postretention patients, the Peer Assessment Rating (PAR) index was measured at the start (T1) and end (T2) of treatment and between 4 and 10 years afterwards (T3). The stability was considered absolute when the T2 and T3 values were identical and relative when the difference was within the ±5 range. Among the 70 patients, 65.8% were female and 34.2% were male. Their mean age was 14.5 years. The mean treatment length was 2.4 years. The mean retention phase was 3.3 years. The mean pre- and posttreatment PAR scores were 29.8 (T1) and 6.3 (T2). The mean T1-T2 difference was 23.6. The mean T2-T3 difference was -0.39. Within the study, 7.1% presented absolute stability and 68.6% presented relative stability. Lower anterior segment alignment and overbite were the most unstable occlusal features and tended to worsen. Fixed retainer (odds ratio [OR] 0.31; 95% confidence interval [CI] 0.10-0.98) as a protective factor and years without retention (OR 1.32; 95% CI 1.03-1.68) as a risk factor are predictor variables of instability in the case of lower anterior segment alignment. The PAR value at the end of treatment (OR 1.29; 95% CI 1.08-1.54) and extractions (OR 4.76; 95% CI 1.05-21.6) before treatment are predictors for midline instability.

  18. Issues and opportunities for small-scale sawmilling in South Africa – An Eastern Cape case study

    CSIR Research Space (South Africa)

    Heyl, L

    2000-01-01

    Full Text Available of privatisation, certification, outgrower schemes and company-community partnerships and presents conclusions and a set of options and next steps for all the main stakeholder groups. Redistribution of opportunities and assets in forestry • Khosa, M. 2000... Certification on the South African Forest Products Supply Chain. This study traces the route of FSC certified timber from mill to market, seeking to understand the impact of certification on traders and retailers in South Africa and the UK. • von Maltitz, G...

  19. A Morphological Study of the Vertebral Venous Plexus and its Connections in the Cape Dune Mole-Rat, Bathyergus suillus (Bathyergidae)

    NARCIS (Netherlands)

    Kotze, S.H.; Boonzaier, J.; Vorster, W.; Hoogland, P.V.J.M.

    2011-01-01

    Bathyergus suillus are subterranean rodents found in the Western Cape of South Africa, where they inhabit sandy, humid burrows. Vertebral venous plexuses around the vertebral column have been implicated in aiding the maintenance of a constant central nervous system temperature via its connections

  20. An exploratory study of what happens to women who are denied abortions in Cape Town, South Africa.

    Science.gov (United States)

    Harries, Jane; Gerdts, Caitlin; Momberg, Mariette; Greene Foster, Diana

    2015-03-21

    Despite the change in legal status of abortion in South Africa in 1996, barriers to access remain. Stigma associated with abortion provision and care, privacy concerns, and negative provider attitudes often discourage women from seeking legal abortion services and sometimes force women outside of the legal system. What happens when women present for abortion at a designated abortion facility and are denied abortions due to gestational limits or other factors-is unknown. Whether women seek care at referral facilities, seek illegal abortion, or carry pregnancies to term has never been documented. This study, part of a multi-country Global Turnaway Study, explored the experiences of women after denial of legal abortion services. Qualitative research methods were used to collect data at two non-governmental organization health care facilities providing abortion services. In depth interviews were held with women 2 to 3 months after they were denied an abortion. Data were analyzed using a thematic analysis approach. The most common reason for being turned away was due to gestational age over 12 weeks with some women denied abortions that day because they did not have enough money to pay for the procedure. Almost all women were extremely upset at being denied an abortion on the day that they visited the health care facility. Some women were so distressed that they openly discussed the option of seeking an illegal provider or exploring the possibility of securing another health care professional who would assist them. Despite South Africa's liberal abortion law and the relatively widespread availability of abortion services in urban settings, women in South Africa are denied abortion services largely due to being beyond the legal limits to obtain an abortion. A high proportion of women who were initially denied an abortion at legal facilities went on to seek options for pregnancy termination outside of the legal system through internet searches--some of which could have

  1. Healthcare provider views on the health effects of biomass fuel collection and use in rural Eastern Cape, South Africa: an ethnographic study.

    Science.gov (United States)

    Matinga, Margaret Njirambo; Annegarn, Harold J; Clancy, Joy S

    2013-11-01

    Policymakers at global level recognise that household biomass use in developing countries has significant health consequences. However, it is unclear how local-level health professionals perceive and respond to such health effects. This paper which is derived from the findings of a larger study on perceptions and responses to the harmful health effects of carrying heavy firewood loads and to smoke from cooking fires is based on a study conducted in South Africa among managers of health programmes and community nurses of Qaukeni and Mhlontlo municipalities in rural Eastern Cape. Interviews and participant observations were conducted in 2009 using ethnographic grounded theory approaches. In addition to a 10-month period of ethnographic fieldwork, ten programme managers and nurses in two villages were interviewed about health patterns in the villages that they serve, their perceptions of, and responses to the health effects of carrying heavy firewood loads, and inhalation of smoke from wood and dung cooking fires, their professional qualifications and experience, their own household energy use; and observations made as they served clinic clients. Results show that these programme managers and nurses perceive the health effects of carrying heavy loads of firewood and of cooking smoke as minor. Sometimes, nurses give women symptomatic relief for musculoskeletal pain resulting from carrying heavy loads. We posit that their perceptions are derived from customary neglect of work-related health and non-communicable diseases, cultural interpretations of womanhood, limited access to relevant information, and limited interactions between health and energy sector professionals. We conclude that culturally and gender-sensitive awareness programmes are needed for local-level health professionals to effectively address health effects of biomass collection and use. This paper provides new insights into overlooked differences between globally-driven initiatives to address health

  2. Addiction and treatment experiences among active methamphetamine users recruited from a township community in Cape Town, South Africa: A mixed-methods study.

    Science.gov (United States)

    Meade, Christina S; Towe, Sheri L; Watt, Melissa H; Lion, Ryan R; Myers, Bronwyn; Skinner, Donald; Kimani, Stephen; Pieterse, Desiree

    2015-07-01

    Since 2000, there has been a dramatic increase in methamphetamine use in South Africa, but little is known about the experiences of out-of-treatment users. This mixed-methods study describes the substance use histories, addiction symptoms, and treatment experiences of a community-recruited sample of methamphetamine users in Cape Town. Using respondent driven sampling, 360 methamphetamine users (44% female) completed structured clinical interviews to assess substance abuse and treatment history and computerized surveys to assess drug-related risks. A sub-sample of 30 participants completed in-depth interviews to qualitatively explore experiences with methamphetamine use and drug treatment. Participants had used methamphetamine for an average of 7.06 years (SD=3.64). They reported using methamphetamine on an average of 23.49 of the past 30 days (SD=8.90); 60% used daily. The majority (90%) met ICD-10 criteria for dependence, and many reported severe social, financial, and legal consequences. While only 10% had ever received drug treatment, 90% reported that they wanted treatment. In the qualitative interviews, participants reported multiple barriers to treatment, including beliefs that treatment is ineffective and relapse is inevitable in their social context. They also identified important motivators, including desires to be drug free and improve family functioning. This study yields valuable information to more effectively respond to emerging methamphetamine epidemics in South Africa and other low- and middle-income countries. Interventions to increase uptake of evidence-based services must actively seek out drug users and build motivation for treatment, and offer continuing care services to prevent relapse. Community education campaigns are also needed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  3. Retinal Microvasculopathy Is Common in HIV/AIDS Patients: A Cross-Sectional Study at the Cape Coast Teaching Hospital, Ghana

    Directory of Open Access Journals (Sweden)

    Emmanuel Kwasi Abu

    2016-01-01

    Full Text Available Purpose. The purpose of this study was to evaluate the ocular disorders in HIV positive patients attending the Cape Coast Teaching Hospital, Ghana. Methods. A cross-sectional study using systematic random sampling was conducted on 295 HIV positive patients. Data collection consisted of semistructured questionnaires, laboratory investigation, medical profile, and ophthalmic examination. Statistical association tests including χ2, independent t-test, and ANOVA were done. A p value ≤ 0.05 was considered statistically significant. Results. Of the 295 participants, 205 (69.5% were on antiretroviral therapy while 90 (30.3% were not on therapy. Majority of the participants (162, 54.9% were in clinical stage two, followed by stages three (68, 23.1%, one (62, 21%, and four (3, 1%, respectively. The overall prevalence of ocular disorders was 5.8%. The most common HIV related ocular disorder was HIV retinal microvasculopathy (58.8%, followed by herpes zoster ophthalmicus and Toxoplasma retinochoroiditis, both representing 11.8% of ocular disorders seen. Cytomegalovirus retinitis, Bell’s palsy, and optic neuritis were the least common (5.9%. CMV retinitis recorded the highest viral load of 1,474,676 copies/mL and mean CD4 count of 136 cells/mm3. The mean CD4 count for participants with HIV related ocular disorders was significantly lower compared to participants without disorders (t=2.5, p=0.012. Participants with ocular disorders also recorded significantly higher mean viral loads than those who did not have ocular disorders (t=2.8, p=0.006. Conclusion. Lower CD4 counts and high viral load copies were associated with the manifestation of HIV related ocular disorders.

  4. Bioengineering case studies sustainable stream bank and slope stabilization

    CERN Document Server

    Goldsmith, Wendi; McCullah, John

    2014-01-01

    This unique volume describes and evaluates 30 projects from across the United States where bio-stabilization was employed to address a detrimental naturally occurring process or byproduct of the built environment. Bio-stabilization (or soil bioengineering) refers to the use of plant materials, primarily live cuttings, arranged in the ground in different arrays to reinforce soils and protect upland slopes and/or stream banks against surficial erosion and shallow slope failures. Examples included in the collection represent different regions of the country and their specific conditions and challenges. Each project is illustrated with a number of distinctive photographs to support the reader's understanding and showcase the wide scope of projects and techniques presented. This book also: ·         Presents a range of well-documented case studies on key techniques and best practices for bio-stabilization projects ·         Emphasizes evaluation and comparison of different techniques and challeng...

  5. Neurodevelopmental outcome of HIV-exposed but uninfected infants in the Mother and Infants Health Study, Cape Town, South Africa.

    Science.gov (United States)

    Springer, Priscilla E; Slogrove, Amy L; Laughton, Barbara; Bettinger, Julie A; Saunders, Henriëtte H; Molteno, Christopher D; Kruger, Mariana

    2018-01-01

    To compare neurodevelopmental outcomes of HIV-exposed uninfected (HEU) and HIV-unexposed uninfected (HUU) infants in a peri-urban South African population. HEU infants living in Africa face unique biological and environmental risks, but uncertainty remains regarding their neurodevelopmental outcome. This is partly due to lack of well-matched HUU comparison groups needed to adjust for confounding factors. This was a prospective cohort study of infants enrolled at birth from a low-risk midwife obstetric facility. At 12 months of age, HEU and HUU infant growth and neurodevelopmental outcomes were compared. Growth was evaluated as WHO weight-for-age, length-for-age, weight-for-length and head-circumference-for-age Z-scores. Neurodevelopmental outcomes were evaluated using the Bayley scales of Infant Development III (BSID) and Alarm Distress Baby Scale (ADBB). Fifty-eight HEU and 38 HUU infants were evaluated at 11-14 months of age. Performance on the BSID did not differ in any of the domains between HEU and HUU infants. The cognitive, language and motor scores were within the average range (US standardised norms). Seven (12%) HEU and 1 (2.6%) HUU infant showed social withdrawal on the ADBB (P = 0.10), while 15 (26%) HEU and 4 (11%) HUU infants showed decreased vocalisation (P = 0.06). There were no growth differences. Three HEU and one HUU infant had minor neurological signs, while eight HEU and two HUU infants had macrocephaly. Although findings on the early neurodevelopmental outcome of HEU infants are reassuring, minor differences in vocalisation and on neurological examination indicate a need for reassessment at a later age. © 2017 John Wiley & Sons Ltd.

  6. Testing the Andrews Framework of Strategy Formulation and Implementation: Case Study of the University of Cape Coast Digital Library in Ghana

    Directory of Open Access Journals (Sweden)

    Nesba Yaa Anima Adzobu

    2014-12-01

    Full Text Available This paper investigates how strategy formulation and implementation processes used by the University of Cape Coast (UCC in building its digital collections compare with the Andrew’s strategic formulation and implementation theoretical framework. Theory-testing case study methodology was used. The data collection instruments were the key informant interview technique and document reviews. During the formulation phase, two aspects (resources and aspirations of senior management were emergent. During the implementation phase, five aspects (achieving results, processes and behaviour, standards, motivation, personal were emergent. All other elements of building the UCC digital collections were planned during both the formulation and implementation phases. Although the emphasis on students and learning is laudable and apt, there seems to be lack of focus on research support beyond digital collection building, despite the fact that research excellence is one of the UCC’s key priorities. Opportunities exist for improving feedback mechanisms between the users, digital library staff and the university management; and inclusion of social media tools in the digital library project. Since only the experience of a single institution of higher learning is considered, it cannot be definitively stated that strategy formulation and implementation will be similar in every institutional context. However, the results provide a basis for academic digital libraries to draw lessons from this case. In African public universities, there is little earlier research on strategy formulation and implementation in digital library management. Strategy formulation and implementation is a critical issue for higher education academic libraries especially in developing countries like Ghana, due to limited financial resources and the rapid change in the information environment during the last several decades.

  7. An integrated environmental risk assessment and management framework for enhancing the sustainability of marine protected areas: the Cape d'Aguilar Marine Reserve case study in Hong Kong.

    Science.gov (United States)

    Xu, Elvis G B; Leung, Kenneth M Y; Morton, Brian; Lee, Joseph H W

    2015-02-01

    Marine protected areas (MPAs), such as marine parks and reserves, contain natural resources of immense value to the environment and mankind. Since MPAs may be situated in close proximity to urbanized areas and influenced by anthropogenic activities (e.g. continuous discharges of contaminated waters), the marine organisms contained in such waters are probably at risk. This study aimed at developing an integrated environmental risk assessment and management (IERAM) framework for enhancing the sustainability of such MPAs. The IERAM framework integrates conventional environmental risk assessment methods with a multi-layer-DPSIR (Driver-Pressure-State-Impact-Response) conceptual approach, which can simplify the complex issues embraced by environmental management strategies and provide logical and concise management information. The IERAM process can generate a useful database, offer timely update on the status of MPAs, and assist in the prioritization of management options. We use the Cape d'Aguilar Marine Reserve in Hong Kong as an example to illustrate the IERAM framework. A comprehensive set of indicators were selected, aggregated and analyzed using this framework. Effects of management practices and programs were also assessed by comparing the temporal distributions of these indicators over a certain timeframe. Based on the obtained results, we have identified the most significant components for safeguarding the integrity of the marine reserve, and indicated the existing information gaps concerned with the management of the reserve. Apart from assessing the MPA's present condition, a successful implementation of the IERAM framework as evocated here would also facilitate better-informed decision-making and, hence, indirectly enhance the protection and conservation of the MPA's marine biodiversity. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Socioeconomic predictors and consequences of depression among primary care attenders with non-communicable diseases in the Western Cape, South Africa: cohort study within a randomised trial.

    Science.gov (United States)

    Folb, Naomi; Lund, Crick; Fairall, Lara R; Timmerman, Venessa; Levitt, Naomi S; Steyn, Krisela; Bachmann, Max O

    2015-11-30

    Socioeconomic predictors and consequences of depression and its treatment were investigated in 4393 adults with specified non-communicable diseases attending 38 public sector primary care clinics in the Eden and Overberg districts of the Western Cape, South Africa. Participants were interviewed at baseline in 2011 and 14 months later, as part of a randomised controlled trial of a guideline-based intervention to improve diagnosis and management of chronic diseases. The 10-item Center for Epidemiologic Studies Depression Scale (CESD-10) was used to assess depression symptoms, with higher scores representing more depressed mood. Higher CESD-10 scores at baseline were independently associated with being less educated (p = 0.004) and having lower income (p = 0.003). CESD-10 scores at follow-up were higher in participants with less education (p = 0.010) or receiving welfare grants (p = 0.007) independent of their baseline scores. Participants with CESD-10 scores of ten or more at baseline (56 % of all participants) had 25 % higher odds of being unemployed at follow-up (p = 0.016), independently of baseline CESD-10 score and treatment status. Among participants with baseline CESD-10 scores of ten or more, antidepressant medication at baseline was independently more likely in participants who had more education (p = 0.002), higher income (p consequence of depression, and may also be a barrier to treatment. There are opportunities for improving the prevention, diagnosis and treatment of depression in primary care in inequitable middle income countries like South Africa. The trial is registered with Current Controlled Trials ( ISRCTN20283604 ).

  9. A new approach to modeling the sediment retention service (InVEST 3.0): Case study of the Cape Fear catchment, North Carolina, USA.

    Science.gov (United States)

    Hamel, Perrine; Chaplin-Kramer, Rebecca; Sim, Sarah; Mueller, Carina

    2015-08-15

    There is a growing call for ecosystem services models that are both simple and scientifically credible, in order to serve public and private sector decision-making processes. Sediment retention receives particular interest given the impact of this service on water quality. We developed a new version of the sediment retention model for the InVEST (Integrated Valuation of Environmental Services and Tradeoffs) tool to address previous limitations and facilitate model uncertainty assessment. We tested the model in the Cape Fear basin, North Carolina (NC), performing sensitivity analyses and assessing its ability to detect the spatial variability in sediment retention service for eight subcatchments. The main advantages of the revised model include the use of spatially-explicit, globally available input data, and the explicit consideration of hydrological connectivity in the landscape. The sensitivity analyses in the study catchment identified the erosivity and erodibility factors, together with the cover factor for agricultural land as the most influential parameter for sediment export. Relative predictions, representing the spatial variability in sediment exports, were correctly represented by the model. Absolute sediment exports were also highly correlated with observations, although their interpretation for socio-economic assessments is more uncertain without local knowledge of the dominant erosion processes. This work confirms that the sediment connectivity approach used in the revised InVEST model has great potential to quantify the sediment retention service. Although resources to conduct model calibration and testing are typically scarce, these practices should be encouraged to improve model interpretation and for confident application in different decision-making contexts. Without calibration, the InVEST sediment model still provides relevant information for ecosystem services assessments, especially in decision contexts that involve ranking of sediment export

  10. Mechanism study on stability enhancement of adefovir dipivoxil by cocrystallization: Degradation kinetics and structure-stability correlation.

    Science.gov (United States)

    Lin, Rui-Zhen; Sun, Peng-Jie; Tao, Qian; Yao, Jia; Chen, Jia-Mei; Lu, Tong-Bu

    2016-03-31

    The purpose of this study is to determine the mechanism by which cocrystallization can enhance the stability of adefovir dipivoxil (AD), a diester prodrug of adefovir with known chemical stability problem. Three multi-component crystals of AD with biologically safe coformers, including gallic acid cocrystal hydrate (1:1:1), salicylate salt (1:1), and maleate salt (1:1) were prepared and characterized by thermal analysis, infrared spectroscopy, powder and single crystal X-ray diffraction. DVS measurements and stability tests were applied to evaluate the stability. The new crystalline phases exhibit improved stability compared to pure drug in the order AD gallic acid cocrystal>AD maleate>AD salicylate>AD form I. Degradation kinetics and structure-stability correlation studies demonstrate that the stability enhancement mechanism by cocrystallization involves (1) inhibition of hydrolysis of AD by replacement of drug-drug homosynthons by stronger drug-coformer heterosynthons at adenine fragments; (2) suppression of dimerization of AD by separation of adenine fragments by inserting coformers in crystal lattices; (3) further reducing rates of hydrolysis by forming hydrogen bonds with hydrate water at phosphoryl fragments. This study has important implications for use of cocrystallization approach to some easily degradable drugs in pharmaceutical. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Experimental and theoretical studies of the colloidal stability of nanoparticles-a general interpretation based on stability maps.

    Science.gov (United States)

    Segets, Doris; Marczak, Renata; Schäfer, Stefan; Paula, Carolin; Gnichwitz, Jan-Frederik; Hirsch, Andreas; Peukert, Wolfgang

    2011-06-28

    The current work addresses the understanding of the stabilization of nanoparticles in suspension. Specifically, we study ZnO in ethanol for which the influence of particle size and reactant ratio as well as surface coverage on colloidal stability in dependence of the purification progress was investigated. The results revealed that the well-known ζ-potential determines not only the colloidal stability but also the surface coverage of acetate groups bound to the particle surface. The acetate groups act as molecular spacers between the nanoparticles and prevent agglomeration. Next to DLVO calculations based on the theory of Derjaguin, Landau, Verwey and Overbeek using a core-shell model we find that the stability is better understood in terms of dimensionless numbers which represent attractive forces as well as electrostatic repulsion, steric effects, transport properties, and particle concentration. Evaluating the colloidal stability in dependence of time by means of UV-vis absorption measurements a stability map for ZnO is derived. From this map it becomes clear that the dimensionless steric contribution to colloidal stability scales with a stability parameter including dimensionless repulsion and attraction as well as particle concentration and diffusivity of the particles according to a power law with an exponent of -0.5. Finally, we show that our approach is valid for other stabilizing molecules like cationic dendrons and is generally applicable for a wide range of other material systems within the limitations of vanishing van der Waals forces in refractive index matched situations, vanishing ζ-potential and systems without a stabilizing shell around the particle surface.

  12. Stability study for matching in laser driven plasma acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, A.R., E-mail: andrea.rossi@mi.infn.it [INFN - MI, via Celoria 16, 20133 Milan (Italy); Anania, M.P. [INFN - LNF, v.le E. Fermi, 00044 Frascati (Italy); Bacci, A. [INFN - MI, via Celoria 16, 20133 Milan (Italy); Belleveglia, M.; Bisesto, F.G.; Chiadroni, E. [INFN - LNF, v.le E. Fermi, 00044 Frascati (Italy); Cianchi, A. [Tor Vergata University, Physics Department, via della Ricerca Scientifica 1, 00133 Rome (Italy); INFN - LNF, v.le E. Fermi, 00044 Frascati (Italy); Curcio, A.; Gallo, A.; Di Giovenale, D.; Di Pirro, G.; Ferrario, M. [INFN - LNF, v.le E. Fermi, 00044 Frascati (Italy); Marocchino, A.; Massimo, F. [La Sapienza University, SBAI Department, via A. Scarpa 14, 00161 Rome (Italy); Mostacci, A. [La Sapienza University, SBAI Department, via A. Scarpa 14, 00161 Rome (Italy); INFN - LNF, v.le E. Fermi, 00044 Frascati (Italy); Petrarca, M. [La Sapienza University, SBAI Department, via A. Scarpa 14, 00161 Rome (Italy); Pompili, R. [INFN - LNF, v.le E. Fermi, 00044 Frascati (Italy); Serafini, L. [INFN - MI, via Celoria 16, 20133 Milan (Italy); Tomassini, P. [University of Milan, Physics Department, via Celoria 16, 20133 Milan (Italy); Vaccarezza, C. [INFN - LNF, v.le E. Fermi, 00044 Frascati (Italy); and others

    2016-09-01

    In a recent paper [14], a scheme for inserting and extracting high brightness electron beams to/from a plasma based acceleration stage was presented and proved to be effective with an ideal bi-Gaussian beam, as could be delivered by a conventional photo-injector. In this paper, we extend that study, assessing the method stability against some jitters in the properties of the injected beam. We find that the effects of jitters in Twiss parameters are not symmetric in results; we find a promising configuration that yields better performances than the setting proposed in [14]. Moreover we show and interpret what happens when the beam charge profiles are modified.

  13. Linear and nonlinear kinetic-stability studies in tokamaks

    International Nuclear Information System (INIS)

    Tang, W.M.; Chance, M.S.; Chen, L.; Krommes, J.A.; Lee, W.W.; Rewoldt, G.

    1982-09-01

    This paper presents results of theoretical investigations on important linear kinetic properties of low frequency instabilities in toroidal systems and on nonlinear processes which could significantly influence their impact on anomalous transport. Analytical and numerical methods and also particle simulations have been employed to carry out these studies. In particular, the following subjects are considered: (1) linear stability analysis of kinetic instabilities for realistic tokamak equilibria and the application of such calculations to the PDX and PLT tokamak experiments including the influence of a hot beam-ion component; (2) determination of nonlinearly saturated, statistically steady states of three interacting drift modes; and (3) gyrokinetic particle simulation of drift instabilities

  14. [Study on stability of curcumine, demethoxycurcumin and bisdemethoxycurcumin].

    Science.gov (United States)

    Han, Gang; Cui, Jing-jing; Bi, Rui; Zhao, Lin-lin; Zhang, Wei-guo

    2008-11-01

    To investigate the stability of curcumin, demethoxycurcumin and bisdemethoxycurcumin in different buffer solution. To determine concentration of curcumin by HPLC when added curcumin, demethoxycurcumin and bisdemethoxycurcumin into the buffer solution the equation of degradation was established. The sequence of stability are bisdemethoxycurcumin > or = demethoxycurcumin > or =curcumin at the same condition. The demethoxycurcumin can stabilize curcumin more strong than the others. The demethoxycurcumin is a nature stabilizing agent for curcumin.

  15. Stability Studies of a Mixture of Paracetamol and Ascorbic Acid ...

    African Journals Online (AJOL)

    Purpose: To determine the effect of the temperature of water used for the preparation of paracetamol and ascorbic acid mixture on its stability, as well as to assess the influence of humidity on the stability of single components and their mixtures. Methods: The stability of the mixtures in aqueous medium was evaluated with ...

  16. Characteristics of clients who access mobile compared to clinic HIV counselling and testing services: a matched study from Cape Town, South Africa.

    Science.gov (United States)

    Meehan, Sue-Ann; Naidoo, Pren; Claassens, Mareli M; Lombard, Carl; Beyers, Nulda

    2014-12-20

    Studies within sub-Saharan African countries have shown that mobile services increase uptake of HIV counselling and testing (HCT) services when compared to clinics and are able to access different populations, but these have included provider-initiated HCT in clinics. This study aimed to compare the characteristics of clients who self-initiated HCT at either a mobile or a clinic service in terms of demographic and socio-economic variables, also comparing reasons for accessing a particular health service provider. This study took place in eight areas around Cape Town. A matched design was used with one mobile HCT service matched with one or more clinics (offering routine HCT services) within each of the eight areas. Adult clients who self-referred for an HIV test within a specified time period at either a mobile or clinic service were invited to participate in the study. Data were collected between February and April 2011 using a questionnaire. Summary statistics were calculated for each service type within a matched pair and differences of outcomes from pairs were used to calculate effect sizes and 95% confidence intervals. 1063 participants enrolled in the study with 511 from mobile and 552 from clinic HCT services. The proportion of males accessing mobile HCT significantly exceeded that of clinic HCT (p mobile HCT was higher than clinic participants (p = 0.023). No significant difference was found for socio-economic variables between participants, with the exception of access to own piped water (p = 0.029). Participants who accessed mobile HCT were significantly more likely to report that they were just passing, deemed an "opportunistic" visit (p = 0.014). Participants who accessed clinics were significantly more likely to report the service being close to home or work (p = 0.035). An HCT strategy incorporating a mobile HCT service, has a definite role to play in reaching those population groups who do not typically access HCT services at a clinic

  17. Is lesional stability in vitiligo more important than disease stability for performing surgical interventions? results from a multicentric study

    Directory of Open Access Journals (Sweden)

    Imran Majid

    2016-01-01

    Full Text Available Background: Ensuring stability of the disease process is essential for undertaking surgical intervention in vitiligo. However, there is no consensus regarding the minimum duration of stability or the relative importance of disease and lesional stability in selecting patients for vitiligo grafting. Aim: This multicentric study aims to assess the relative importance of lesional and disease stability on selecting patients for vitiligo grafting. Materials and Methods: One hundred seventy patients were recruited into the study and divided into two groups: Group A with lesional stability of >1 year but overall disease stability of only 6-11 months and Group B with overall disease stability of >1 year. Patients underwent either tissue or cellular vitiligo grafting on the selected lesions and the repigmentation achieved was scored from 0 (no repigmentation to 6 (100% repigmentation. Repigmentation achieved on different sites of the body was compared between the two groups. Adverse effects at both the donor and the recipient sites were also compared. Results: Of the 170 patients who were enrolled, 82 patients were placed in Group A and 88 patients in Group B. Average repigmentation achieved (on scale of 0 to 6 was 3.8 and 4.04 in Group A and Group B, respectively. In Group A, ≥90% repigmentation was achieved in 36.6% (30/82 patients, while 37.5% (33/88 achieved similar results in Group B. Additionally, 47.6% (39/82 and 53.4% (47/88 of cases achieved partial repigmentation in Group A and Group B, respectively. Perigraft halo was the commonest adverse effect observed in both groups. Statistical analysis revealed no significant differences between the two groups with respect to the repigmentation achieved or adverse effects observed. Repigmentation achieved was the best on the face and neck area, while acral areas responded the least. Conclusions: Lesional stability seems to be as relevant as the overall disease stability in selecting patients for

  18. Study of nonlinear system stability using eigenvalue analysis: Gyroscopic motion

    Science.gov (United States)

    Shabana, Ahmed A.; Zaher, Mohamed H.; Recuero, Antonio M.; Rathod, Cheta

    2011-11-01

    orientation parameters and also to shed light on the important issue of using the eigenvalue analysis in the study of MBS stability. The validity of using the eigenvalue analysis based on the linearization of the nonlinear equations of motion in the study of the stability of railroad vehicle systems, which have known critical speeds, is examined. It is shown that such an eigenvalue analysis can lead to wrong conclusions regarding the stability of nonlinear systems.

  19. Prevalence of Taenia solium cysticercosis in swine from a community-based study in 21 villages of the Eastern Cape Province, South Africa

    OpenAIRE

    Krecek, R C; Michael, L M; Schantz, P M; Ntanjana, L; Smith, M F; Dorny, P; Harrison, L J S; Grimm, F; Praet, N; Willingham, A L

    2008-01-01

    The pork tapeworm, Taenia solium, causative organism of porcine cysticercosis and human neurocysticercosis is known to occur in areas of South Africa including Eastern Cape Province but, despite increasing reports of its occurrence throughout the subregion, the prevalence is yet to be clearly established. The parasite presents a potentially serious agricultural problem and public health risk in endemic areas. The human populations considered to be at highest risk of infection with this zoonot...

  20. Stability study of sodium colistimethate-loaded lipid nanoparticles.

    Science.gov (United States)

    Moreno-Sastre, M; Pastor, M; Esquisabel, A; Sans, E; Viñas, M; Bachiller, D; Pedraz, J L

    2016-11-01

    In the last decades, the encapsulation of antibiotics into nanoparticulate carriers has gained increasing attention for the treatment of infectious diseases. Sodium colistimethate-loaded solid lipid nanoparticles (Colist-SLNs) and nanostructured lipid carriers (Colist-NLCs) were designed aiming to treat the pulmonary infection associated to cystic fibrosis patients. The nanoparticles were freeze-dried using trehalose as cryoprotectant. The stability of both nanoparticles was analysed over one year according to the International Conference of Harmonisation (ICH) guidelines by determining the minimum inhibitory concentration (MIC) against clinically isolated Pseudomonas aeruginosa strains and by studying their physico-chemical characteristics. The results showed that Colist-SLNs lost their antimicrobial activity at the third month; on the contrary, the antibacterial activity of Colist-NLCs was maintained throughout the study within an adequate range (MIC ≤16 μg/mL). In addition, Colist-NLCs exhibited suitable physico-chemical properties at 5 °C and 25 °C/60% relative humidity over one year. Altogether, Colist-NLCs proved to have better stability than Colist-SLNs.

  1. Biophysical Studies of Function and Stability in Adenylosuccinate Lyase

    Science.gov (United States)

    Ray, Stephen; Duval, Nathan; Wilkinson, Terry, II; Shaheen, Sean; Ghosh, Kinshuk; Patterson, David

    2012-10-01

    Adenylosuccinate Lyase (ADSL) is a homotetrameric protein with four active sites that accommodate two reactions in the de novo purine biosynthesis pathway. It catalyzes the conversion of SAICAR to AICAR and AMPS to AMP. Point mutations in the gene encoding the protein ADSL lead to ADSL deficiency, a disorder characterized by serious neurological and physiological symptoms. Two leading hypotheses regarding the pathogenesis are ``Loss of Function'' or ``Gain in Toxic Function.'' These hypotheses can be related to the reduction of either the enzyme kinetics or the stability of the tetramer structure. Enzymatic studies can be used to provide a quantitative measure of the extent to which the enzyme acts on its designated substrates, SAICAR and AMPS. Recent kinetic studies have measured activity only on the substrates independently. Here we present characterization of enzyme kinetics for the biophysically interesting and physiologically relevant case where two substrates exhibit competitive binding to the enzyme, for both wild type and disease causing mutants of ADSL. Preliminary data suggest equivalent specific activities may be necessary to suppress severe phenotypes from expressing. Additionally, we will present results on the role of mutations on the thermodynamic stability of the enzyme. We will discuss thermodynamic analysis that gives a direct quantitative measure of the propensity of formation of folded and unfolded states of the protein, which influence the functionality of the protein and may also influence aggregation.

  2. Feasibility, yield, and cost of active tuberculosis case finding linked to a mobile HIV service in Cape Town, South Africa: a cross-sectional study.

    Science.gov (United States)

    Kranzer, Katharina; Lawn, Stephen D; Meyer-Rath, Gesine; Vassall, Anna; Raditlhalo, Eudoxia; Govindasamy, Darshini; van Schaik, Nienke; Wood, Robin; Bekker, Linda-Gail

    2012-01-01

    The World Health Organization is currently developing guidelines on screening for tuberculosis disease to inform national screening strategies. This process is complicated by significant gaps in knowledge regarding mass screening. This study aimed to assess feasibility, uptake, yield, treatment outcomes, and costs of adding an active tuberculosis case-finding program to an existing mobile HIV testing service. The study was conducted at a mobile HIV testing service operating in deprived communities in Cape Town, South Africa. All HIV-negative individuals with symptoms suggestive of tuberculosis, and all HIV-positive individuals regardless of symptoms were eligible for participation and referred for sputum induction. Samples were examined by microscopy and culture. Active tuberculosis case finding was conducted on 181 days at 58 different sites. Of the 6,309 adults who accessed the mobile clinic, 1,385 were eligible and 1,130 (81.6%) were enrolled. The prevalence of smear-positive tuberculosis was 2.2% (95% CI 1.1-4.0), 3.3% (95% CI 1.4-6.4), and 0.4% (95% CI 1.4 015-6.4) in HIV-negative individuals, individuals newly diagnosed with HIV, and known HIV, respectively. The corresponding prevalence of culture-positive tuberculosis was 5.3% (95% CI 3.5-7.7), 7.4% (95% CI 4.5-11.5), 4.3% (95% CI 2.3-7.4), respectively. Of the 56 new tuberculosis cases detected, 42 started tuberculosis treatment and 34 (81.0%) completed treatment. The cost of the intervention was US$1,117 per tuberculosis case detected and US$2,458 per tuberculosis case cured. The generalisability of the study is limited to similar settings with comparable levels of deprivation and TB and HIV prevalence. Mobile active tuberculosis case finding in deprived populations with a high burden of HIV and tuberculosis is feasible, has a high uptake, yield, and treatment success. Further work is now required to examine cost-effectiveness and affordability and whether and how the same results may be achieved at scale.

  3. Multidisciplinary Studies of the Fate and Transport of Contaminants in Ground Water at the U.S. Geological Survey Cape Cod Toxic Substances Hydrology Program Research Site, Massachusetts

    Science.gov (United States)

    Leblanc, D. R.; Smith, R. L.; Kent, D. B.; Barber, L. B.; Harvey, R. W.

    2008-12-01

    The U.S. Geological Survey conducts multidisciplinary research on the physical, chemical, and microbiological processes affecting ground-water contaminants of global concern at its Cape Cod Toxic Substances Hydrology Program site in Massachusetts, USA. The work centers on a 6-kilometer-long plume of treated wastewater in a glacial sand and gravel aquifer. The plume is characterized by distinct geochemical zones caused by the biodegradation of organic materials in treated wastewater that was disposed to the aquifer by rapid infiltration during the period 1936-95. A core group of hydrogeologists, geochemists, microbiologists, and geophysicists has been involved in the research effort for more than two decades. The effort has been enhanced by stable funding, a readily accessible site, a relatively simple hydrologic setting, and logistical support from an adjacent military base. The research team uses a three-part approach to plan and conduct research at the site. First, detailed spatial and temporal monitoring of the plume since the late 1970s provides field evidence of important contaminant-transport processes and provides the basis for multidisciplinary, process-oriented studies. Second, ground-water tracer experiments are conducted in various geochemical zones in the plume to study factors that control the rate and extent of contaminant transport. Several arrays of multilevel sampling devices, including an array with more than 15,000 individual sampling points, are used to conduct these experiments. Plume-scale (kilometers) and tracer-test-scale (1- 100 meters) studies are complemented by laboratory experiments and mathematical modeling of flow and reactive transport. Third, results are applied to the treated-wastewater plume, other contaminant plumes at the military base, and other sites nationally to evaluate the applicability of the findings and to point toward further research. Examples of findings to date include that (1) macrodispersivity can be related to

  4. Perspectives of wild medicine harvesters from Cape Town, South Africa

    Directory of Open Access Journals (Sweden)

    Leif Petersen

    2017-09-01

    Full Text Available Cape Town is a fast-growing cityscape in the Cape Floristic Region in South Africa with 24 formally protected conservation areas including the World Heritage Table Mountain National Park. These sites have been protected and managed as critical sites for local biodiversity, representing potentially one-third of all Cape Floristic Region flora species and 18% of South Africa's plant diversity. Cape Town is also inhabited by a rapidly growing culturally and economically diverse citizenry with distinct and potentially conflicting perspectives on access to, and management of, local natural resources. In a qualitative study of 58 locally resident traditional healers of distinct cultural groups, we examined motivations underlying the generally illicit activity of harvesting of wild resources from Cape Town protected areas. Resource harvester motivations primarily link to local economic survival, health care and cultural links to particular resources and practices, 'access for all' outlooks, and wholesale profit-seeking perspectives. We describe these motivations, contrast them with the current formal, legal and institutional perspectives for biodiversity protection in the city, and propose managerial interventions that may improve sustainability of ongoing harvest activities. Significance: The study reveals, for the first time in the Cape Floristic Region, informal economy viewpoints on terrestrial nature and how its direct use has important economic and cultural roles – specifically in wild medicine harvesting and trade. We contrast the formal and informal approaches to nature conservation in the city and propose new considerations for conservation managers.

  5. GREENHOUSE-GROWN CAPE GOOSEBERRY

    African Journals Online (AJOL)

    industry to make jam, sauce, pies, puddings, chutneneys, ice cream and fruit salads (Facciola,. 1990; Huxley, 1992). The processed products can then be sold to earn fairly good income and even be exported to earn foreign exchange. Despite the good natural flavour of the Kenyan. Cape gooseberry fruit and the potential to.

  6. Thermal Stabilization study of polyacrylonitrile fiber obtained by extrusion

    Directory of Open Access Journals (Sweden)

    Robson Fleming Ribeiro

    2015-12-01

    Full Text Available A low cost and environmental friendly extrusion process of the Polyacrylonitrile (PAN polymer was viabilized by using the 1,2,3-propanetriol (glycerol as a plasticizer. The characterization of the fibers obtained by this process was the object of study in the present work. The PAN fibers were heat treated in the range of 200 °C to 300 °C, which is the temperature range related to the stabilization/oxidation step. This is a limiting phase during the carbon fiber processing. The characterization of the fibers was made using infrared spectroscopy, thermal analysis and microscopy. TGA revealed that the degradation of the extruded PAN co-VA fibers between 250 °C and 350 °C, corresponded to a 9% weight loss to samples analyzed under oxidizing atmosphere and 18% when the samples were analyzed under inert atmosphere. DSC showed that the exothermic reactions on the extruded PAN co-VA fibers under oxidizing synthetic air was broader and the cyclization started at a lower temperature compared under inert atmosphere. Furthermore, FT-IR analysis correlated with thermal anlysis showed that the stabilization/oxidation process of the extruded PAN fiber were coherent with other works that used PAN fibers obtained by other spinning processes.

  7. Novel self-assembling nanogels: stability and lyophilisation studies.

    Science.gov (United States)

    Daoud-Mahammed, S; Couvreur, P; Gref, R

    2007-03-06

    The stability of new supramolecular nanoassemblies (nanogels), based on the association of a hydrophobically modified dextran (MD) and a beta-cyclodextrin polymer (pbetaCD), has been studied by two complementary methods: (i) size measurements and (ii) turbidity experiments using a Turbiscan optical analyser. Nanogels of about 120-150nm were obtained whatever the concentration of the two polymer solutions. At low concentrations, the suspensions presented little mean diameter variations upon storage. However, the concentrated ones tended to destabilize and their mean diameter increased upon time. Size measurements and Turbiscan investigations have demonstrated that destabilization in the MD-pbetaCD nanogel suspension was only due to particle aggregation and/or fusion, as no sedimentation or creaming occurred. The destabilization of MD-pbetaCD suspensions led to the formation of a highly viscous phase, as a final state. Moreover, the two methods have shown that aggregation and/or fusion phenomena were more pronounced in the concentrated MD-pbetaCD suspensions than in the diluted ones. The stability of MD-pbetaCD suspensions could be improved by their storage at 4 degrees C. Finally, freeze-drying was found to be a convenient method for the long-time storage of MD-pbetaCD nanoassemblies.

  8. Stability study: Transparent conducting oxides in chemically reactive plasmas

    Science.gov (United States)

    Manjunatha, Krishna Nama; Paul, Shashi

    2017-12-01

    Effect of plasma treatment on transparent conductive oxides (TCOs) including indium-doped tin oxide (ITO), fluorine-doped tin oxide (FTO) and aluminium-doped zinc oxide (AZO) are discussed. Stability of electrical and optical properties of TCOs, when exposed to plasma species generated from gases such as hydrogen and silane, are studied extensively. ITO and FTO thin films are unstable and reduce to their counterparts such as Indium and Tin when subjected to plasma. On the other hand, AZO is not only stable but also shows superior electrical and optical properties. The stability of AZO makes it suitable for electronic applications, such as solar cells and transistors that are fabricated under plasma environment. TCOs exposed to plasma with different fabrication parameters are used in the fabrication of silicon nanowire solar cells. The performance of solar cells, which is mired by the plasma, fabricated on ITO and FTO is discussed with respect to plasma exposure parameters while showing the advantages of using chemically stable AZO as an ideal TCO for solar cells. Additionally, in-situ diagnostic tool (optical emission spectroscopy) is used to monitor the deposition process and damage caused to TCOs.

  9. Contribution to the study of superconductor thermal stability

    International Nuclear Information System (INIS)

    Meuris, Chantal.

    1982-06-01

    The fundamental problem consists in ensuring, a priori, that transitions from the superconducting state to the normal resistive state, created by thermal disturbances, resorb spontaneously. An analysis of the validity limits of the criteria generally used leads to the definition of a certain number of unsolved problems raised by two particular configurations linked to the present technology of large superconducting magnets. The thermal stability is studied in relation to disturbances leading to a dispersion of heat in the conductor. The first configuration is representative of that of magnets with cooling channels defined transversely to the conductor and communicating with the main helium source (for example toroidal coil of Tore Supra). The uneven distribution of coolant along the conductor, due to the presence of the insulating supports marking the channels, leads to possible states for the conductor which were not anticipated till now. A theoretical study is developed of the stable and unstable stationary states of the conductor and the respective attraction fields of the stable states. A complete digital analysis of the dynamics of the state of the disturbed system is then made. This digital simulation is compared with the experimental results. The second configuration relates to the case of a conductor cooled by a limited volume of superfluid helium, for example a cable with internal cooling by static superfluid helium. An analysis of the cooling medium enables a theoretical relation to be established between the usable enthalpy and the time distribution of the thermal disturbance. This culminates in a fresh stability and dimensioning criterion of the cooling system with respect to the type of disturbances. An experimental study confirms this theory [fr

  10. 33 CFR 165.530 - Safety Zone: Cape Fear and Northeast Cape Fear Rivers, NC.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone: Cape Fear and Northeast Cape Fear Rivers, NC. 165.530 Section 165.530 Navigation and Navigable Waters COAST GUARD... § 165.530 Safety Zone: Cape Fear and Northeast Cape Fear Rivers, NC. (a) Location. The following area is...

  11. Green Tea Leaves Extract: Microencapsulation, Physicochemical and Storage Stability Study.

    Science.gov (United States)

    Zokti, James A; Sham Baharin, Badlishah; Mohammed, Abdulkarim Sabo; Abas, Faridah

    2016-07-26

    Green tea polyphenols have been reported to possess many biological properties. Despite the many potential benefits of green tea extracts, their sensitivity to high temperature, pH and oxygen is a major disadvantage hindering their effective utilization in the food industry. Green tea leaves from the Cameron Highlands Malaysia were extracted using supercritical fluid extraction (SFE). To improve the stability, green tea extracts were encapsulated by spray-drying using different carrier materials including maltodextrin (MD), gum arabic (GA) and chitosan (CTS) and their combinations at different ratios. Encapsulation efficiency, total phenolic content and antioxidant capacity were determined and were found to be in the range of 71.41%-88.04%, 19.32-24.90 (g GAE/100 g), and 29.52%-38.05% respectively. Further analysis of moisture content, water activity, hygroscopicity, bulk density and mean particles size distribution of the microparticles were carried out and the results ranged from; 2.31%-5.11%, 0.28-0.36, 3.22%-4.71%, 0.22-0.28 g/cm³ and 40.43-225.64 µm respectively. The ability of the microparticles to swell in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) was determined as 142.00%-188.63% and 207.55%-231.77%, respectively. Release of catechin polyphenol from microparticles in SIF was higher comparable to that of SGF. Storage stability of encapsulated catechin extracts under different temperature conditions was remarkably improved compared to non-encapsulated extract powder. This study showed that total catechin, total phenolic content (TPC) and antioxidant activity did not decrease significantly (p ≥ 0.05) under 4 °C storage conditions. The half-life study results were in the range of 35-60, 34-65 and 231-288 weeks at storage temperatures of 40 °C, 25 °C and 4 °C respectively, therefore, for improved shelf-life stability we recommend that microparticles should be stored at temperatures below 25 °C.

  12. Green Tea Leaves Extract: Microencapsulation, Physicochemical and Storage Stability Study

    Directory of Open Access Journals (Sweden)

    James A. Zokti

    2016-07-01

    Full Text Available Green tea polyphenols have been reported to possess many biological properties. Despite the many potential benefits of green tea extracts, their sensitivity to high temperature, pH and oxygen is a major disadvantage hindering their effective utilization in the food industry. Green tea leaves from the Cameron Highlands Malaysia were extracted using supercritical fluid extraction (SFE. To improve the stability, green tea extracts were encapsulated by spray-drying using different carrier materials including maltodextrin (MD, gum arabic (GA and chitosan (CTS and their combinations at different ratios. Encapsulation efficiency, total phenolic content and antioxidant capacity were determined and were found to be in the range of 71.41%–88.04%, 19.32–24.90 (g GAE/100 g, and 29.52%–38.05% respectively. Further analysis of moisture content, water activity, hygroscopicity, bulk density and mean particles size distribution of the microparticles were carried out and the results ranged from; 2.31%–5.11%, 0.28–0.36, 3.22%–4.71%, 0.22–0.28 g/cm3 and 40.43–225.64 µm respectively. The ability of the microparticles to swell in simulated gastric fluid (SGF and simulated intestinal fluid (SIF was determined as 142.00%–188.63% and 207.55%–231.77%, respectively. Release of catechin polyphenol from microparticles in SIF was higher comparable to that of SGF. Storage stability of encapsulated catechin extracts under different temperature conditions was remarkably improved compared to non-encapsulated extract powder. This study showed that total catechin, total phenolic content (TPC and antioxidant activity did not decrease significantly (p ≥ 0.05 under 4 °C storage conditions. The half-life study results were in the range of 35–60, 34–65 and 231–288 weeks at storage temperatures of 40 °C, 25 °C and 4 °C respectively, therefore, for improved shelf-life stability we recommend that microparticles should be stored at temperatures below 25 °C.

  13. 76 FR 38302 - Safety Zone; Cape Charles Fireworks, Cape Charles Harbor, Cape Charles, VA

    Science.gov (United States)

    2011-06-30

    ... Cape Charles City Harbor centered on position 37[deg]15'46.5'' N/076[deg]01'30'' W (NAD 1983). Due to... of materials, performance, design, or operation; test methods; sampling procedures; and related... the human environment. This rule is categorically excluded, under figure 2-1, paragraph (34)(g), of...

  14. Stability studies on refined soybean oil stored in various conditions

    International Nuclear Information System (INIS)

    Arawande, J.O.; Amoo, I.A.

    2008-01-01

    The 12 months stability study of freshly produced refined soybean oil revealed that refined soybean oil stored in plastic containers in dark was more hydrolytically and oxidatively stable than that stored in other containers in light condition. There was no significant difference at P < 0.05 in free fatty acids and acid value of oil stored under light and dark conditions in tin and glass containers but there was significant difference at P < 0.05 in peroxide value of oil stored in light and dark conditions in all the storage containers. Light increased the degree of oxidative rancidity of refined soybean oil, the most in tin containers, followed by glass containers and the least in plastic containers. (author)

  15. Plutonium Finishing Plant. Interim plutonium stabilization engineering study

    Energy Technology Data Exchange (ETDEWEB)

    Sevigny, G.J.; Gallucci, R.H.; Garrett, S.M.K.; Geeting, J.G.H.; Goheen, R.S.; Molton, P.M.; Templeton, K.J.; Villegas, A.J. [Pacific Northwest Lab., Richland, WA (United States); Nass, R. [Nuclear Fuel Services, Inc. (United States)

    1995-08-01

    This report provides the results of an engineering study that evaluated the available technologies for stabilizing the plutonium stored at the Plutonium Finishing Plant located at the hanford Site in southeastern Washington. Further processing of the plutonium may be required to prepare the plutonium for interim (<50 years) storage. Specifically this document provides the current plutonium inventory and characterization, the initial screening process, and the process descriptions and flowsheets of the technologies that passed the initial screening. The conclusions and recommendations also are provided. The information contained in this report will be used to assist in the preparation of the environmental impact statement and to help decision makers determine which is the preferred technology to process the plutonium for interim storage.

  16. Mechanical Stability Study for Integrable Optics Test Accelerator at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    McGee, Mike [Fermilab; Andrews, Richard [Fermilab; Carlson, Kermit [Fermilab; Leibfritz, Jerry [Fermilab; Nobrega, Lucy [Fermilab; Valishev, Alexander [Fermilab

    2016-07-01

    The Integrable Optics Test Accelerator (IOTA) is proposed for operation at Fermilab. The goal of IOTA is to create practical nonlinear accelerator focusing systems with a large frequency spread and stable particle motion. The IOTA is a 40 m circumference, 150 MeV (e-), 2.5 MeV (p⁺) diagnostic test ring. A heavy low frequency steel floor girder is proposed as the primary tier for IOTA device component support. Two design lengths; (8) 4 m and (2) 2.8 m long girders with identical cross section completely encompass the ring. This study focuses on the 4 m length girder and the development of a working prototype. Hydrostatic Level Sensor (HLS), temperature, metrology and fast motion measurements characterize the anticipated mechanical stability of the IOTA ring.

  17. Stability analysis and support study on surroundings of finishing cut

    Energy Technology Data Exchange (ETDEWEB)

    Xu, J.; Miao, X.; Lu, A.; Xing, C. [CUMT, Jiangsu (China). College of Mineral and Energy Resources

    2003-09-01

    By means of finishing cut the trackless rubber-tried vehicle can directly go to the working face to remove the equipment. It can promote the efficiency in removing the equipment. Because of the finishing cut continuously affected by the dynamic pressure of face, it is important to find the reasonable position of the finishing cut and the proportion support. Based on the study of the ground pressure and the moving law of overlying strata during the terminal mining in sublevel caving face, the optimal position and the proportion support way of finishing cut were obtained using experiment with analog simulation and numerical simulation. This method can keep the stability for the surroundings of the finishing cut and lay the foundation for finishing the face quickly and safely. The engineering practice shows this technique is efficient and the significant social and economy benefit is obtained. 7 refs.,11 figs.

  18. SiPM Gain Stabilization Studies for Adaptive Power Supply

    CERN Document Server

    AUTHOR|(CDS)2074257; Zalieckas, Justas; Cvach, Jaroslav; Kvasnicka, Jiri; Polak, Ivo

    2016-01-01

    We present herein gain stabilization studies of SiPMs using a climate chamber at CERN. We present results for four detectors not tested before, three from Hamamatsu and one from KETEK. Two of the Hamamatsu SiPMs are novel sensors with trenches that reduce cross talk. We use an improved readout system with a digital oscilloscope controlled with a dedicated LabView program. We improved and automized the analysis to deal with large datasets. We have measured the gain-versus-bias-voltage dependence at fixed temperature and gain-versus-temperature dependence at fixed bias voltage to determine the bias voltage dependence on temperature $V(T)$ for stable gain. We show that the gain remains stable to better than $\\pm 0.5\\%$ in the $20^\\circ \\rm C - 30^\\circ C$ temperature range if the bias voltage is properly adjusted with temperature.

  19. Plutonium Finishing Plant. Interim plutonium stabilization engineering study

    International Nuclear Information System (INIS)

    Sevigny, G.J.; Gallucci, R.H.; Garrett, S.M.K.; Geeting, J.G.H.; Goheen, R.S.; Molton, P.M.; Templeton, K.J.; Villegas, A.J.; Nass, R.

    1995-08-01

    This report provides the results of an engineering study that evaluated the available technologies for stabilizing the plutonium stored at the Plutonium Finishing Plant located at the hanford Site in southeastern Washington. Further processing of the plutonium may be required to prepare the plutonium for interim (<50 years) storage. Specifically this document provides the current plutonium inventory and characterization, the initial screening process, and the process descriptions and flowsheets of the technologies that passed the initial screening. The conclusions and recommendations also are provided. The information contained in this report will be used to assist in the preparation of the environmental impact statement and to help decision makers determine which is the preferred technology to process the plutonium for interim storage

  20. Experimental studies of flame stability limits of biogas flame

    International Nuclear Information System (INIS)

    Dai Wanneng; Qin Chaokui; Chen Zhiguang; Tong Chao; Liu Pengjun

    2012-01-01

    Highlights: ► Premixed biogas flame stability for RTBs was studied on different conditions. ► An unusual “float off” phenomenon was observed. ► Decrease of port diameter or gas temperature or methane content motivates lifting. ► Increase of methane content or gas temperature or port diameter motivates yellow tipping. ► Lifting curves become straight lines when semi-logarithmic graph paper is applied. - Abstract: Flame stability of premixed biogas flame for Reference Test Burner (RTB) was investigated. In this study, six kinds of test gases were used to simulate biogas in which CO 2 volume fraction varied from 30% to 45%. A series of experiments were conducted on two RTBs with different port diameters and at different outlet unburned mixture temperatures. It was found that the lifting and yellow tipping limits show similar trends regardless of the biogas components, port diameters and mixture temperatures. A “float off” phenomenon could be observed at low gas flow rate and low primary air ratio. Low mixture temperature, small ports and high CO 2 concentration in biogas can lead to the unstable condition of “float off”. The lifting limits are enhanced with an increase of port diameter or mixture temperature and with a decrease of CO 2 concentration. The yellow tipping limits are extended with an increase of CO 2 concentration and with a decrease of mixture temperature or port diameter. In addition, the lifting limit curve becomes a straight line when semi-logarithmic graph paper is applied. The intercept increases with a decrease of the CO 2 concentration in biogas and with an increase of port diameter or gas temperature.

  1. Gold nanoparticles prepared using cape aloe active components.

    Science.gov (United States)

    Krpetić, Zeljka; Scarì, Giorgio; Caneva, Enrico; Speranza, Giovanna; Porta, Francesca

    2009-07-07

    A novel use of two components of Cape aloe, aloin A and aloesin, acting as stabilizers in the preparation of gold and silver nanoparticles, is reported. Stable water-soluble particles of different size and shape are prepared by varying the reaction conditions, temperature, reaction time, and reducing agents. Characterization of the obtained particles is performed using UV-visible, attenuated total reflection Fourier transform infrared (ATR-FTIR), and 1H NMR spectroscopies and transmission electron microscopy (TEM). The efficient cellular uptake of 50 nm sized aloin A and aloesin stabilized gold particles into macrophages and HeLa cells was investigated, proposing these particles as nanovehicles.

  2. Studies on dispersive stabilization of porous media flows

    Energy Technology Data Exchange (ETDEWEB)

    Daripa, Prabir, E-mail: prabir.daripa@math.tamu.edu; Gin, Craig [Department of Mathematics, Texas A& M University, College Station, Texas 77843 (United States)

    2016-08-15

    Motivated by a need to improve the performance of chemical enhanced oil recovery (EOR) processes, we investigate dispersive effects on the linear stability of three-layer porous media flow models of EOR for two different types of interfaces: permeable and impermeable interfaces. Results presented are relevant for the design of smarter interfaces in the available parameter space of capillary number, Peclet number, longitudinal and transverse dispersion, and the viscous profile of the middle layer. The stabilization capacity of each of these two interfaces is explored numerically and conditions for complete dispersive stabilization are identified for each of these two types of interfaces. Key results obtained are (i) three-layer porous media flows with permeable interfaces can be almost completely stabilized by diffusion if the optimal viscous profile is chosen, (ii) flows with impermeable interfaces can also be almost completely stabilized for short time, but become more unstable at later times because diffusion flattens out the basic viscous profile, (iii) diffusion stabilizes short waves more than long waves which leads to a “turning point” Peclet number at which short and long waves have the same growth rate, and (iv) mechanical dispersion further stabilizes flows with permeable interfaces but in some cases has a destabilizing effect for flows with impermeable interfaces, which is a surprising result. These results are then used to give a comparison of the two types of interfaces. It is found that for most values of the flow parameters, permeable interfaces suppress flow instability more than impermeable interfaces.

  3. Western Cape, South Africa

    African Journals Online (AJOL)

    This permits safe artificial recharge of the various water quality portions at different points in the aquifer, either for recycling ... transferred to other potential sites for establishment of similar systems in arid and semi-arid areas of South Africa and the ... studies from over 50 countries from Europe, Asia, Africa, North and South ...

  4. Surgical stabilization of internal pneumatic stabilization? A prospective randomized study of management of severe flail chest patients.

    Science.gov (United States)

    Tanaka, Hideharu; Yukioka, Tetsuo; Yamaguti, Yoshihiro; Shimizu, Syoichiro; Goto, Hideaki; Matsuda, Hiroharu; Shimazaki, Syuji

    2002-04-01

    We compared the clinical efficacy of surgical stabilization and internal pneumatic stabilization in severe flail chest patients who required prolonged ventilatory support. Thirty-seven consecutive severe flail chest patients who required mechanical ventilation were enrolled in this study. All the patients received identical respiratory management, including end-tracheal intubation, mechanical ventilation, continuous epidural anesthesia, analgesia, bronchoscopic aspiration, postural drainage, and pulmonary hygiene. At 5 days after injury, surgical stabilization with Judet struts (S group, n = 18) or internal pneumatic stabilization (I group, n = 19) was randomly assigned. Most respiratory management was identical between the two groups except the surgical procedure. Statistical analysis using two-way analysis of variance and Tukey's test was used to compare the groups. Age, sex, Injury Severity Score, chest Abbreviated Injury Score, number of rib fractures, severity of lung contusion, and Pao2/Fio2 ratio at admission were all equivalent in the two groups. The S group showed a shorter ventilatory period (10.8 +/- 3.4 days) than the I group (18.3 +/- 7.4 days) (p < 0.05), shorter intensive care unit stay (S group, 16.5 +/- 7.4 days; I group, 26.8 +/- 13.2 days; p < 0.05), and lower incidence of pneumonia (S group, 24%; I group, 77%; p < 0.05). Percent forced vital capacity was higher in the S group at 1 month and thereafter (p < 0.05). The percentage of patients who had returned to full-time employment at 6 months was significantly higher in the S group (11 of 18) than in the I group (1 of 19). This study proved that in severe flail chest patients, surgical stabilization using Judet struts has beneficial effects with respect to less ventilatory support, lower incidence of pneumonia, shorter trauma intensive care unit stay, and reduced medical cost than internal fixation. Moreover, surgical stabilization with Judet struts improved percent forced vital capacity from the

  5. Guidelines for the practical stability studies of anticancer drugs: A european consensus conference

    NARCIS (Netherlands)

    C. Bardin (Christophe); A. Astier (A.); A.G. Vulto (Arnold); G. Sewell (G.); J. Vigneron (J.); R. Trittler (R.); M. Daouphars (M.); M.C. Paul (Muriel); M. Trojniak (M.); F. Pinguet (F.)

    2012-01-01

    textabstractStability studies performed by the pharmaceutical industry are only designed to fulfil licensing requirements. Thus post-dilution or reconstitution stability data are frequently limited to 24 h only for bacteriological reasons, regardless of the true chemical stability, which could, in

  6. SPECTRAL ANALYSIS OF GAS BEARING SYSTEMS FOR STABILITY STUDIES

    Science.gov (United States)

    latter case is given in terms of a herringbone-grooved journal bearing . This method of stability analysis is applicable to both thrust and journal bearings for both whirl and pneumatic-hammer instabilities.

  7. Treatment guidelines and early loss from care for people living with HIV in Cape Town, South Africa: A retrospective cohort study.

    Directory of Open Access Journals (Sweden)

    Ingrid T Katz

    2017-11-01

    Full Text Available South Africa has undergone multiple expansions in antiretroviral therapy (ART eligibility from an initial CD4+ threshold of ≤200 cells/μl to providing ART for all people living with HIV (PLWH as of September 2016. We evaluated the association of programmatic changes in ART eligibility with loss from care, both prior to ART initiation and within the first 16 weeks of starting treatment, during a period of programmatic expansion to ART treatment at CD4+ ≤ 350 cells/μl.We performed a retrospective cohort study of 4,025 treatment-eligible, non-pregnant PLWH accessing care in a community health center in Gugulethu Township affiliated with the Desmond Tutu HIV Centre in Cape Town. The median age of participants was 34 years (IQR 28-41 years, almost 62% were female, and the median CD4+ count was 173 cells/μl (IQR 92-254 cells/μl. Participants were stratified into 2 cohorts: an early cohort, enrolled into care at the health center from 1 January 2009 to 31 August 2011, when guidelines mandated that ART initiation required CD4+ ≤ 200 cells/μl, pregnancy, advanced clinical symptoms (World Health Organization [WHO] stage 4, or comorbidity (active tuberculosis; and a later cohort, enrolled into care from 1 September 2011 to 31 December 2013, when the treatment threshold had been expanded to CD4+ ≤ 350 cells/μl. Demographic and clinical factors were compared before and after the policy change using chi-squared tests to identify potentially confounding covariates, and logistic regression models were used to estimate the risk of pre-treatment (pre-ART loss from care and early loss within the first 16 weeks on treatment, adjusting for age, baseline CD4+, and WHO stage. Compared with participants in the later cohort, participants in the earlier cohort had significantly more advanced disease: median CD4+ 146 cells/μl versus 214 cells/μl (p < 0.001, 61.1% WHO stage 3/4 disease versus 42.8% (p < 0.001, and pre-ART mortality of 34.2% versus 16.7% (p

  8. Anatomic Aspects of Formation and Growth of the Cape Gooseberry Fruit Physalis peruviana (Solanaceae)

    OpenAIRE

    Manuel Fernando Mazorra; Ángela Patricia Quintana; Diego Miranda; Gerhard Fischer; Martha Chaparro de Valencia

    2006-01-01

    The anatomical changes in reproductive structures were observed and described frrom button to mature fruit and the phenological states and the structural development of the Cape gooseberry fruit, ecotype Colombia, were established settled down. This investigation was made in a commercial Cape gooseberry (Physalis peruviana) orchard located in the municipality of Granada, Cundinamarca, Colombia. The study confirmed that anatomically the Cape gooseberry fruits, ecotipo Colombia, and ruderal ...

  9. Studying the stabilization of vegetable pigments using 14C

    International Nuclear Information System (INIS)

    Inanejshvili, Zh.A.; Prokof'eva, M.C.

    1975-01-01

    With the help of labeled cathine tea-leaf substance it has been discovered that the later forms a specific complex with the red beet pigment. This obviously appears to be the reason for the pigment stability. An increase of the labeled cathine substance portion taken to stabilize the red pigment leads to lowering down the portion of the labeled pigment taking part in the reaction. The results from the experiment can be practically used in food industry for plant pigments

  10. Resistive Wall Mode Stabilization Studies at DIII-D

    International Nuclear Information System (INIS)

    Garofalo, A.M.

    2005-01-01

    The effort to understand the physics of the resistive wall mode (RWM) and develop methods to control this magnetohydrodynamic mode to allow achievement of higher pressure in advanced tokamak plasmas has been an example of successful multi-institutional collaboration at the DIII-D National Fusion Facility in San Diego, California. DIII-D research in this area has produced several advances and breakthroughs following a coordinated research plan involving a sequence of measurements, development of new analysis tools, and the installation of new diagnostic and feedback stabilization hardware: Suppression of the RWM by active magnetic feedback has been demonstrated using the DIII-D six-element error field correction coil, rotational stabilization of the RWM has been demonstrated and sustained for all values of the plasma pressure from the no-wall to the ideal-wall stability limits, improved RWM feedback stabilization has been shown using a new set of 12 internal control coils, and newly developed models of feedback have shown good agreement with the measurements. By so doing, the DIII-D work on RWM stabilization has become a cornerstone of the long-term advanced tokamak program and is having impact on the world fusion program. Presently both ITER and FIRE are including plans for RWM stabilization in their programs

  11. Experimental Vertical Stability Studies for ITER Performance and Design Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Humphreys, D A; Casper, T A; Eidietis, N; Ferrera, M; Gates, D A; Hutchinson, I H; Jackson, G L; Kolemen, E; Leuer, J A; Lister, J; LoDestro, L L; Meyer, W H; Pearlstein, L D; Sartori, F; Walker, M L; Welander, A S; Wolfe, S M

    2008-10-13

    Operating experimental devices have provided key inputs to the design process for ITER axisymmetric control. In particular, experiments have quantified controllability and robustness requirements in the presence of realistic noise and disturbance environments, which are difficult or impossible to characterize with modeling and simulation alone. This kind of information is particularly critical for ITER vertical control, which poses some of the highest demands on poloidal field system performance, since the consequences of loss of vertical control can be very severe. The present work describes results of multi-machine studies performed under a joint ITPA experiment on fundamental vertical control performance and controllability limits. We present experimental results from Alcator C-Mod, DIII-D, NSTX, TCV, and JET, along with analysis of these data to provide vertical control performance guidance to ITER. Useful metrics to quantify this control performance include the stability margin and maximum controllable vertical displacement. Theoretical analysis of the maximum controllable vertical displacement suggests effective approaches to improving performance in terms of this metric, with implications for ITER design modifications. Typical levels of noise in the vertical position measurement which can challenge the vertical control loop are assessed and analyzed.

  12. A stability study of plasma polymerized acrylic acid films

    Science.gov (United States)

    Cools, Pieter; Declercq, Heidi; De Geyter, Nathalie; Morent, Rino

    2018-02-01

    A medium pressure parallel-plate DBD set-up was used for the deposition of carboxylic acid-rich films using acrylic acid as precursor. A variety of discharge powers (21-33 W) and monomer flow rates (0.25-0.5 g/h) were applied to develop a range of coatings from highly unstable to completely stable in aqueous solutions. FT-IR and XPS were used to identify which coatings were stable under dynamic incubation conditions and what influence plasma operating parameters had on functional group preservation. White light interferometry was also used to calculate deposition rates (66-126 nm/min) and to determine the deposition regime (monomer deficient). Human foreskin fibroblasts were seeded onto the complete range of investigated samples and the effects of coating (in)stability on cell adhesion, viability and morphology were systematically studied. Results showed that the 27 W-0.25 g/h treatment conditions resulted in the most stable coatings. Although a concentration of only 0.7% of carboxylic acid groups was found under these experimental conditions, the positive effects of a highly acid-rich surface were still maintained as cell-material interactions were significantly enhanced.

  13. Environmental stability study of holographic solar spectrum splitting materials

    Science.gov (United States)

    Chrysler, Benjamin D.; Ayala Pelaez, Silvana; Wu, Yuechen; Vorndran, Shelby D.; Kostuk, Raymond K.

    2016-09-01

    In this study the impact of outdoor temperature variations and solar illumination exposure on spectral filter material and holographic optical elements is examined. Although holographic components have been shown to be useful for solar spectrum splitting designs, relatively little quantitative data exist to demonstrate the extent to which these materials can withstand outdoor conditions. As researchers seek to investigate practical spectrum splitting designs, the environmental stability of holographic materials should be considered as an important factor. In the experiment presented, two holographic materials, Covestro Bayfol HX photopolymer and dichromated gelatin, and 3M reflective polymer filter materials are exposed to outdoor conditions for a period of several months. The environmental effect on absorption, spectral and angular bandwidth, peak efficiency, and Bragg matching conditions for the holograms are examined. Spectral bandwidth and transmittance of the 3M reflective filter material are also monitored. Holographic gratings are recorded, measured, and mounted on glass substrates and then sealed with a glass cover plate. The test samples are then mounted on a photovoltaic panel to simulate realistic temperature conditions and placed at an outdoor test facility in Tucson, Arizona. A duplicate set of holograms and 3M filter material is stored as a control group and periodically compared over the test period.

  14. Thermo-hydraulic stability study of a steam generator

    International Nuclear Information System (INIS)

    Magni, M C; Marcel, C P; Delmastro, D F

    2012-01-01

    In this work a mathematical model developed to investigate the thermalhydraulic stability of a helically coiled steam generator is presented. Such a steam generator is prone to experiment density wave oscillations. The model is therefore used to analyze the stability of the CAREM-25 reactor steam generators. The model is linear, numerically non-diffusive and nodal. In addition, it is able to represent non-uniform heat transfer fluxes between the primary and secondary coolant circuits. By using this model the marginal stability condition is found by varying the inlet friction coefficient for different conditions. The results are then compared with those obtained with a different model for which a simple uniform heat flux profiled is assumed. It is found that with such simplification the density waves instability mechanism is overestimated in a wide range of operating powers. For very low powers, in the contrary, the so-called uniform model underestimates the stabilizing inlet friction and therefore it gives non-conservative results. With the use of the more realistic non-uniform power profile model, it was possible to determine that, for a CAREM-25 steam generator, the most stable conditions is found at 60MW when the reactor operates at nominal pressure. Moreover, it is found that at high power levels the stability performance is dominated by the two-phase friction component while at low power levels the friction component originated in the over heated steam region prevail (author)

  15. "Not on the agenda": A qualitative study of influences on health services use among poor young women who use drugs in Cape Town, South Africa.

    Science.gov (United States)

    Myers, Bronwyn; Carney, Tara; Wechsberg, Wendee M

    2016-04-01

    Poor young women who use alcohol and other drugs (AODs) in Cape Town, South Africa, need access to health services to prevent HIV. Efforts to link young women to services are hampered by limited information on what influences service initiation. We explored perceptions of factors that influence poor AOD-using young women's use of health services. We conducted four focus groups with young women (aged 16-21) who used AODs and were recruited from two township communities in Cape Town. We also conducted 14 in-depth interviews with health and social welfare service planners and providers. Discussion topics included young women's use of health services and perceived influences on service use. Qualitative data were analysed using a framework approach. The findings highlighted structural, contextual, and systemic influences on the use of health services by young women who use AODs. First, young women were absent from the health agenda, which had an impact on the provision of women-specific services. Resource constraints and gender inequality were thought to contribute to this absence. Second, gender inequality and stigma toward young women who used AODs led to their social exclusion from education and employment opportunities and health care. Third, community poverty resulted in the emergence of perverse social capital and social disorder that limited social support for treatment. Fourth, the health care system was unresponsive to the multiple service needs of these young women. To reach young women who use AODs, interventions need to take cognisance of young women's risk environment and health systems need to adapt to respond better to their needs. For these interventions to be effective, gender must be placed on the policy agenda. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Newborn follow-up after discharge from a tertiary care hospital in the Western Cape region of South Africa: a prospective observational cohort study.

    Science.gov (United States)

    Milambo, Jean Paul Muambangu; Cho, KaWing; Okwundu, Charles; Olowoyeye, Abiola; Ndayisaba, Leonidas; Chand, Sanjay; Corden, Mark H

    2018-01-01

    Current practice in the Western Cape region of South Africa is to discharge newborns born in-hospital within 24 h following uncomplicated vaginal delivery and two days after caesarean section. Mothers are instructed to bring their newborn to a clinic after discharge for a health assessment. We sought to determine the rate of newborn follow-up visits and the potential barriers to timely follow-up. Mother-newborn dyads at Tygerberg Hospital in Cape Town, South Africa were enrolled from November 2014 to April 2015. Demographic data were obtained via questionnaire and medical records. Mothers were contacted one week after discharge to determine if they had brought their newborns for a follow-up visit, and if not, the barriers to follow-up. Factors associated with follow-up were analyzed using logistic regression. Of 972 newborns, 794 (82%) were seen at a clinic for a follow-up visit within one week of discharge. Mothers with a higher education level or whose newborns were less than 37 weeks were more likely to follow up. The follow-up rate did not differ based on hospital length of stay. Main reported barriers to follow-up included maternal illness, lack of money for transportation, and mother felt follow-up was unnecessary because newborn was healthy. Nearly 4 in 5 newborns were seen at a clinic within one week after hospital discharge, in keeping with local practice guidelines. Further research on the outcomes of this population and those who fail to follow up is needed to determine the impact of postnatal healthcare policy.

  17. Study Addiction: A Cross-Cultural Longitudinal Study Examining Temporal Stability and Predictors of Its Changes

    OpenAIRE

    Atroszko, Pawe? Andrzej; Andreassen, Cecilie Schou; Griffiths, Mark D.; Pallesen, St?le

    2016-01-01

    Background and aims: "Study addiction" has recently been conceptualized as a behavioral addiction and defined within the framework of work addiction. Using a newly developed measure to assess this construct, the Bergen Study Addiction Scale (BStAS), the present study examined the 1-year stability of study addiction and factors related to changes in this construct over time, and is the first longitudinal investigation of study addiction thus far. \\ud Methods: The BStAS and the Ten Item Persona...

  18. A valuation study of fuel supply stability of nuclear energy

    International Nuclear Information System (INIS)

    Nagano, Koji; Nagata, Yutaka; Hitomi, Kazumi; Hamagata, Sumio; Asaoka, Yoshiyuki

    2008-01-01

    In order to assess potential benefits of nuclear power with regard to its characteristics of fuel supply stability, the following three aspects are valuated under the Japanese energy and electricity mix: a) economic stability; i.e. nuclear power's contribution to the whole energy and electricity mix in terms of resistance to fluctuation and/or fuel price hikes, b) procurement stability; i.e. natural uranium, the raw fuel material for nuclear power generation, is being imported from more reliable sources through adequately diverse markets than in the cases of oil and natural gas, and, c) passive reserve effect; i.e. fuel materials as running stocks at power stations and fuel service facilities could maintain nuclear power generation running for a certain duration under unexpected disruption of fuel supply. (author)

  19. Defining Anaerobic Digestion Stability-Full Scale Study

    Science.gov (United States)

    Demitry, M. E., Sr.

    2014-12-01

    A full-scale anaerobic digester receiving a mixture of primary and secondary sludge was monitored for one hundred days. A chemical oxygen demand, COD, and a volatile solids, VS, mass balance was conducted to evaluate the stability of the digester and its capability of producing methane gas. The COD mass balance could account for nearly 90% of the methane gas produced while the VS mass balance showed that 91% of the organic matter removed resulted in biogas formation. Other parameters monitored included: pH, alkalinity, VFA, and propionic acid. The values of these parameters showed that steady state had occurred. Finally, at mesophilic temperature and at steady state performance, the anaerobic digester stability was defined as a constant ratio of methane produced per substrate of ΔVS (average ratio=0.404 l/g). This ratio can be used as universal metric to determine the anaerobic digester stability in an easy and inexpensive way.

  20. Ultrasonic Studies of Emulsion Stability in the Presence of Magnetic Nanoparticles

    Directory of Open Access Journals (Sweden)

    A. Józefczak

    2015-01-01

    Full Text Available Pickering emulsions are made of solid particle-stabilized droplets suspended in an immiscible continuous liquid phase. A magnetic emulsion can be obtained using magnetic particles. Solid magnetic nanoparticles are adsorbed strongly at the oil-water interface and are able to stabilize emulsions of oil and water. In this work emulsions stabilized by magnetite nanoparticles were obtained using high-energy ultrasound waves and a cavitation mechanism and, next, their stability in time was tested by means of acoustic waves with a low energy, without affecting the structure. An acoustic study showed high stability in time of magnetic emulsions stabilized by magnetite particles. The study also showed a strong influence of an external magnetic field, which can lead to changes of the emulsion properties. It is possible to control Pickering emulsion stability with the help of an external stimulus—a magnetic field.

  1. Stability Study of ATF 80MeV Injector Linac

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, Douglas

    2003-06-09

    A beam stability test was carried out at ATF 80 MeV injector linac. The test was performed by taking data of each monitor in pulse to pulse base. A data acquisition system which consists of a PC and a GPIB network was used for the test. In order to analyze the data, ''Correlation Plot'' method is used which is effective to find out some source of the observed beam fluctuation. This paper describes the result of the stability measurement and the comparison between ATF injector and SLC injector.

  2. Panorama das pesquisas sobre TDIC e formação de professores de língua inglesa em LA: um levantamento bibliográfico a partir da base de dissertações/teses da CAPES Overview of the researches about DICT and English Teacher Education in Al: a bibliographical study based on CAPES database of theses and dissertations

    Directory of Open Access Journals (Sweden)

    Lucas Moreira dos Anjos Santos

    2013-03-01

    Full Text Available Esse trabalho tem por objetivo apresentar um panorama das pesquisas sobre Tecnologias Digitais de Informação e Comunicação (TDIC e formação de professores de língua inglesa desenvolvidas no âmbito da Linguística Aplicada no Brasil entre os anos de 2000 a 2009. A fim de atingir o objetivo, foi realizada uma busca bibliográfica no banco de teses e dissertações da CAPES a partir de termos chaves no campo assunto. Como resultados, apontamos uma ampla variedade de estudos que se voltam para tal área evidenciando diferentes focos: na transposição de políticas públicas, no uso de ferramentas digitais para formação (inicial e continuada de professores, na apropriação de ferramentas digitais pelo professor na sua prática pedagógica, nas crenças e representações construídas a partir do uso de ferramentas tecnológicas, dentre outros. Esperamos contribuir para um mapeamento da literatura já desenvolvida na área de formação de professores de língua inglesa e TDIC para a realização de futuras pesquisas.This paper aims at presenting an overview of the researches about Digital Information and Communication Technologies (DICT and English teacher education carried in Applied Linguistics in Brazil from 2000 to 2009. In order to do so, a bibliographical search was carried out at the CAPES database of theses and dissertations according to some key words related to this subject. The results point out a number of varied studies developed in this field with different focus such as: public policies and its implementation, use of digital tools in pre and in service teacher education, appropriation of digital tools by teachers into their work, believes and representations concerning the use of digital tools, among others. We hope to contribute to those who further wish to develop more studies under the theme English teacher education and DICT.

  3. Stability and Comparative Dissolution Studies of Five Brands of ...

    African Journals Online (AJOL)

    The dissolution profiles of five different brands of norfloxacin (400 mg) tablets designated as A, B, C, D, and E, marketed in Addis Ababa were compared with those of an innovator product (F). The stability of these tablets was evaluated under the influence of accelerated conditions (40 °C + 2 °C and 75% ± 5% RH).

  4. Fabrication and thermal stability studies of polyamide 66 containing ...

    Indian Academy of Sciences (India)

    During fabrication of FR-PA66, melt polymerization time exhibits more surprising influence on intrinsic viscosity than aqueous solution polymerization time. The LOI value of FR-PA66 with 9 wt% TPO reaches 27.2, and corresponding UL94 rating reaches V-0. Improved thermo-stability of FR-PA66 can be attributed to both ...

  5. Accelerated Stability Studies of Three Local Drug Products Prone to ...

    African Journals Online (AJOL)

    Three locally manufactured drug products, Aspirin 300 mg tablets, Chloramphenicol 250 mg capsules and Ampicillin Trihydrate 500 mg capsules, obtained from three production batches, were exposed to storageconditions maintained at 40 °C and 75% relative humidity (RH) in a stability chamber. The products were ...

  6. Studies of iso-alpha-acids : analysis, purification, and stability.

    NARCIS (Netherlands)

    Khatib, Alfi

    2006-01-01

    The female cones of hop (Humulus lupulus L.) are added to beer, providing taste and flavour and contributing to the stability of foam. The main constituents of hop related to these properties are generically known as alpha-acids. During the brewing process, these acids are isomerized, resulting in

  7. Stability of the human spine: a biomechanical study

    NARCIS (Netherlands)

    Scholten, P.J.M.; Veldhuizen, A.G.; Grootenboer, H.J.

    1988-01-01

    The influences of curvatures and of physical properties on the mechanical stability of the spine were analysed by means of a three-dimensional, geometrical, nonlinear biomechanical model. According to the model, the initial buckling load decreases with increasing lordotic and kyphotic curvatures.

  8. AMPR BRIGHTNESS TEMPERATURE CAPE EXPERIMENT V2

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced Microwave Precipitation Radiometer (AMPR) was deployed during the Convection and Precipitation / Electrification Experiment (CaPE). AMPR data were...

  9. AMPR BRIGHTNESS TEMPERATURE CAPE EXPERIMENT V2

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced Microwave Precipitation Radiometer (AMPR) was deployed during the Convection and Precipitation/Electrification Experiment (CaPE). AMPR data...

  10. 46 CFR 7.45 - Cape Henlopen, DE to Cape Charles, VA.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Cape Henlopen, DE to Cape Charles, VA. 7.45 Section 7.45... Atlantic Coast § 7.45 Cape Henlopen, DE to Cape Charles, VA. (a) A line drawn from the easternmost extremity of Indian River Inlet North Jetty to latitude 38°36.5′ N. longitude 75°02.8′ W. (Indian River...

  11. 46 CFR 7.55 - Cape Henry, VA to Cape Fear, NC.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Cape Henry, VA to Cape Fear, NC. 7.55 Section 7.55 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC BOUNDARY LINES Atlantic Coast § 7.55 Cape Henry, VA to Cape Fear, NC. (a) A line drawn from Rudee Inlet Jetty Light “2” to...

  12. A Developed Graphical User Interface for Power System Stability and Robustness Studies

    OpenAIRE

    GHOURAF Djamel Eddine; NACERI Abdellatif; ABID Mohamed; KABI Wahiba

    2015-01-01

    This paper present the realization and development of a graphical user interface (GUI) to studied the stability and robustness of power systems (analysis and synthesis), using Conventional Power System Stabilizers (CPSS - realized on PID scheme) or advanced controllers (based on adaptive and robust control), and applied on automatic excitation control of powerful synchronous generators, to improve dynamic performances and robustness. The GUI is a useful average to facilitate stability study o...

  13. Prevalence and determinants of unplanned pregnancy in HIV-positive and HIV-negative pregnant women in Cape Town, South Africa: a cross-sectional study.

    Science.gov (United States)

    Iyun, Victoria; Brittain, Kirsty; Phillips, Tamsin K; le Roux, Stanzi; McIntyre, James A; Zerbe, Allison; Petro, Greg; Abrams, Elaine J; Myer, Landon

    2018-04-03

    Prevention of unplanned pregnancy is a crucial aspect of preventing mother-to-child HIV transmission. There are few data investigating how HIV status and use of antiretroviral therapy (ART) may influence pregnancy planning in high HIV burden settings. Our objective was to examine the prevalence and determinants of unplanned pregnancy among HIV-positive and HIV-negative women in Cape Town, South Africa. Cross-sectional analysis. Single primary-level antenatal care clinic in Cape Town, South Africa. HIV-positive and HIV-negative pregnant women, booking for antenatal care from March 2013 to August 2015, were included. Unplanned pregnancy was measured at the first antenatal care visit using the London Measure of Unplanned Pregnancy (LMUP). Analyses examined LMUP scores across four groups of participants defined by their HIV status, awareness of their HIV status prior to the current pregnancy and/or whether they were using antiretroviral therapy (ART) prior to the current pregnancy. Among 2105 pregnant women (1512 HIV positive; 593 HIV negative), median age was 28 years, 43% were married/cohabiting and 20% were nulliparous. Levels of unplanned pregnancy were significantly higher in HIV-positive versus HIV-negative women (50% vs 33%, p<0.001); and highest in women who were known HIV positive but not on ART (53%). After adjusting for age, parity and marital status, unplanned pregnancy was most common among women newly diagnosed and women who were known HIV positive but not on ART (compared with HIV-negative women, adjusted OR (aOR): 1.43; 95% CI 1.05 to 1.94 and aOR: 1.57; 95% CI 1.13 to 2.15, respectively). Increased parity and younger age (<24 years) were also associated with unplanned pregnancy (aOR: 1.42; 95% CI 1.25 to 1.60 and aOR: 1.83; 95% CI 1.23 to 2.74, respectively). We observed high levels of unplanned pregnancy among HIV-positive women, particularly among those not on ART, suggesting ongoing missed opportunities for improved family planning and

  14. Strategic Analysis for the MER Cape Verde Approach

    Science.gov (United States)

    Gaines, Daniel; Belluta, Paolo; Herman, Jennifer; Hwang, Pauline; Mukai, Ryan; Porter, Dan; Jones, Byron; Wood, Eric; Grotzinger, John; Edgar, Lauren; hide

    2009-01-01

    The Mars Exploration Rover Opportunity has recently completed a two year campaign studying Victoria Crater. The campaign culminated in a close approach of Cape Verde in order to acquire high resolution imagery of the exposed stratigraphy in the cliff face. The close approach to Cape Verde provided significant challenges for every subsystem of the rover as the rover needed to traverse difficult, uncharacterised terrain and approach a cliff face with the potential of blocking out solar energy and communications with Earth. In this paper we describe the strategic analyses performed by the science and engineering teams so that we could successfully achieve the science objectives while keeping the rover safe.

  15. 33 CFR 80.505 - Cape Henlopen, DE to Cape Charles, VA.

    Science.gov (United States)

    2010-07-01

    ... to Cape Charles, VA. (a) A line drawn from the seaward extremity of Indian River Inlet North Jetty to Indian River Inlet South Jetty Light. (b) A line drawn from Ocean City Inlet Light 6, 225° true across... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Cape Henlopen, DE to Cape Charles...

  16. Quality assurance in the foundation phase in the Eastern Cape ...

    African Journals Online (AJOL)

    The main focus of this study was whether and how provision is made to enhance the quality of education in the Foundation Phase. After a case study investigation into a primary school and its view on quality assurance and interviews with the Department of Education: Eastern Cape province it became apparent that more ...

  17. Methamphetamine use and sexual risk behaviour in Cape Town ...

    African Journals Online (AJOL)

    Objective: Community studies and studies of admissions to drug treatment centers indicate a dramatic increase in the prevalence of methamphetamine use in Cape Town since 2003. There has also been a substantial increase over this time period in the prevalence of HIV infection among women attending public antenatal ...

  18. Van Willebrand's disease in the Western Cape | Bird | South African ...

    African Journals Online (AJOL)

    Haemophilia clinics at two tertiary referral hospitals (Groote Schuur Hospital and Red Cross War Memorial Children's Hospital) in the Westem Cape. Patients. Twenty-two patients (t 4 females, 8 males; ages 3 - 55 years) were studied. Those studied were selected for reasons of convenience, as they were compliant and ...

  19. Tuberous sclerosis complex in the Western Cape, South Africa: The ...

    African Journals Online (AJOL)

    Tuberous sclerosis complex (TSC) is a genetic neurocutaneous condition, which affects multiple organ systems. This study aimed to determine the presenting features of children with TSC in Cape Town, South Africa. A cross-sectional study was conducted at a TSC clinic, and clinical features at presentation were ...

  20. Cable Stability

    CERN Document Server

    Bottura, L

    2014-01-01

    Superconductor stability is at the core of the design of any successful cable and magnet application. This chapter reviews the initial understanding of the stability mechanism, and reviews matters of importance for stability such as the nature and magnitude of the perturbation spectrum and the cooling mechanisms. Various stability strategies are studied, providing criteria that depend on the desired design and operating conditions.

  1. Sodium tetraphenylborate solution stability: A long term study

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, M.J.

    1992-06-11

    Sodium tetraphenylborata (NaTPB) is a specialty chemical required for the In Tank Precipitation Process (ITP). It precipitates cesium, aiding in the decontamination of high level radioactive waste solutions. Long term stability of aqueous alkaline solutions of NATPB has been investigated. The focus of the investigation is on the relative stabilities of NATPB solutions exposed to varying temperatures and copper concentrations over an extended period of time. Additionally, vendor-supplied samples, incubated at 40{degree}C, were stored for more than a year without decomposing. Collected data demonstrates that in the absence of elevated copper concentrations, NATPB solutions will remain stable for periods of 1 to 2 years (at a minimum) at maximum expected operating conditions (<40{degree}C). Additionally, biuret, (H{sub 2}NCO){sub 2}NH, was tested as an additive to prevent copper-induced decomposition without success.

  2. Sodium tetraphenylborate solution stability: A long term study

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, M.J.

    1992-06-11

    Sodium tetraphenylborata (NaTPB) is a specialty chemical required for the In Tank Precipitation Process (ITP). It precipitates cesium, aiding in the decontamination of high level radioactive waste solutions. Long term stability of aqueous alkaline solutions of NATPB has been investigated. The focus of the investigation is on the relative stabilities of NATPB solutions exposed to varying temperatures and copper concentrations over an extended period of time. Additionally, vendor-supplied samples, incubated at 40[degree]C, were stored for more than a year without decomposing. Collected data demonstrates that in the absence of elevated copper concentrations, NATPB solutions will remain stable for periods of 1 to 2 years (at a minimum) at maximum expected operating conditions (<40[degree]C). Additionally, biuret, (H[sub 2]NCO)[sub 2]NH, was tested as an additive to prevent copper-induced decomposition without success.

  3. Comparative study of probabilistic methodologies for small signal stability assessment

    Energy Technology Data Exchange (ETDEWEB)

    Rueda, J.L.; Colome, D.G. [Universidad Nacional de San Juan (IEE-UNSJ), San Juan (Argentina). Inst. de Energia Electrica], Emails: joseluisrt@iee.unsj.edu.ar, colome@iee.unsj.edu.ar

    2009-07-01

    Traditional deterministic approaches for small signal stability assessment (SSSA) are unable to properly reflect the existing uncertainties in real power systems. Hence, the probabilistic analysis of small signal stability (SSS) is attracting more attention by power system engineers. This paper discusses and compares two probabilistic methodologies for SSSA, which are based on the two point estimation method and the so-called Monte Carlo method, respectively. The comparisons are based on the results obtained for several power systems of different sizes and with different SSS performance. It is demonstrated that although with an analytical approach the amount of computation of probabilistic SSSA can be reduced, the different degrees of approximations that are adopted, lead to deceptive results. Conversely, Monte Carlo based probabilistic SSSA can be carried out with reasonable computational effort while holding satisfactory estimation precision. (author)

  4. [Study on retention and stability of linear occlusal complete dentures].

    Science.gov (United States)

    Zhang, Ping; Xu, Jun

    2003-01-01

    To learn retention and stability of linear occlusal complete dentures by investigating the subjective feelings of patient and the value of retention force. Static retention forces of maxillary and mandibular dentures were measured for 25 patients wearing linear occlusal dentures by using Hz-1 retention dynamometer. The subjective feelings of patients in functional state were gained simultaneously through questionnaire. Linear occlusal dentures demonstrate good retention in static and dynamic state. Among patients with severe resorption of residual ridge (RRR), mandibular linear occlusal dentures (shown good retentive subjective feelings) demonstrate significantly smaller retention force than those with slight or medium degree of RRR. There is no correlation between the subjective feelings and the values of retention forces of mandibular dentures. The subjective feelings of patients wearing new linear occlusal dentures are much better than that of old anatomic occlusal dentures. Linear occlusal dentures improve the performances of dentures by enhancing their stability during mastication movement.

  5. Study of TBP stability limits in pyrolysis, radiolysis and hydrolysis

    International Nuclear Information System (INIS)

    Azzouz, A.; Attou, M.

    1985-10-01

    The present investigations deal with the determination of the stability limits of different degradation phenomena during TBP process achievement, its purification, storage or in radioelements extraction. The results were obtained using a simple and quick analysis method based on TBP:HC104 complex formation. The TBP is considered stable (when its degradation rate is less than 0,5% Vol.) for temperature less than 100 0 C and time contact value of about 2 hours. It was depicted that TBP has an appreciable stability under the following conditions: NaOH 0,1 N/TBP=0,5 ml/ml and time contact <4 hours; POC13/TBP=0,02 ml/ml and time contact <1 hour; concentrated acid/TBP=0,025 ml/ml and time contact <1 h. Radiation cumulative effect seems to be the main precursor of TBP degradation. However, its stability remains appreciable under certain conditions. Practically, in all the cases, TBP decomposition is mainly tied to C-O bond breakdown

  6. Diversity of influences on infant feeding strategies in women living with HIV in Cape Town, South Africa: a mixed methods study.

    Science.gov (United States)

    Zulliger, Rose; Abrams, Elaine J; Myer, Landon

    2013-12-01

    To explore influences on infant feeding intentions and practices in women living with HIV in South Africa. Structured questionnaires were completed by 207 pregnant women and 203 post-partum women in Cape Town, South Africa. Concurrently, 34 semi-structured, qualitative interviews explored the influences on infant feeding strategies in women living with HIV. Overall, 50% (104) of pregnant women intended to breastfeed and 22% (45) of post-partum women ever breastfed. Women who breastfed or intended to breastfeed were significantly more likely to have running water in their homes, to have formal housing and to receive advice in support of breastfeeding. Advice from clinic staff was the strongest predictor of breastfeeding [adjusted relative odds (ARO) in pregnant women: 6.87; 95% confidence interval (CI): 2.67, 17.66; ARO in post-partum women: 4.04; 95% CI: 1.60, 10.19]. Other important influences included previous infant feeding experiences, desires to protect the infant from HIV and involvement of other care providers. Many women also noted that breastfeeding was not feasible due to work commitments and highlighted concerns around the discontinuation of the free provision of infant formula. These results suggest that women living with HIV balance complex influences in deciding on their preferred infant feeding strategies. This underscores the need for extensive provider, patient and community education to ensure consistent messaging, while allowing for adaptation to the circumstances of individual mothers. © 2013 John Wiley & Sons Ltd.

  7. Supporting Teacher Professional Development to Use Tablets in Resource Constrained Schools: A Case Study of Cofimvaba Schools, Eastern Cape Province, South Africa

    Directory of Open Access Journals (Sweden)

    Adele Botha

    2015-08-01

    Full Text Available Over a period of three years, 360 teachers at 26 resource constrained schools in Cofimvaba, which lies in the Nciba district of the Eastern Cape Province of South Africa, have received training on how to integrate mobile tablets in their classrooms to support teaching and learning. The training modules combined the use of teaching strategies and fun with practical hands-on exercises which can be used in any type of subject for any grade when training teachers. Teachers embarked on a learning path attached to badges to reward their efforts and evidence of how they have applied their training in their classrooms. The purpose of this paper is to share this novel approach to teacher training in a unique context where schools are deprived of resources but still managed to successfully integrate mobile tablets in their classroom practices. These practices have changed the way teachers teach from standing with a textbook and chalk in front of a class sitting in rows, to standing with a tablet and learners are engaged in group work and using the tablets as a resource in a disconnected environment. The success of these training modules lies in the application of an approach of teach with and not to, earn as you learn and not just give technology, respect and humility, flexibility, innovation, creativity and co-creation.

  8. Knowledge and use of emergency contraception among women in the Western Cape province of South Africa: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Smit Jennifer

    2007-09-01

    Full Text Available Abstract Background Emergency contraception (EC is widely available free of charge at public sector clinics in South Africa. At the same time, rates of teenage and unintended pregnancy in South Africa remain high, and there are few data on knowledge of EC in the general population in South Africa, as in other resource-limited settings. Methods We conducted a cross-sectional, interviewer-administered survey among 831 sexually active women at 26 randomly selected public sector clinics in the Western Cape province. Results Overall, 30% of the women had ever heard of EC when asked directly, after the method was described to them. Only 15% mentioned EC by name or description spontaneously. Knowledge of EC was independently associated with higher education, being married, and living in an urban setting. Four percent of women had ever used EC. Discussion These data suggest that knowledge of EC in this setting is more common among women of higher socioeconomic status living in urban areas. For EC to play a role in decreasing unintended pregnancy in South Africa, specific interventions are necessary to increase knowledge of the method, where to get it, and the appropriate time interval for its use before the need for EC arises. Future health promotion campaigns should target rural and low socioeconomic status communities.

  9. Anemia and associated factors among school-age children in Cape ...

    African Journals Online (AJOL)

    Anemia is a problem affecting a large group of school children in sub-Saharan Africa, contributing to morbidity in this region. In Cape Verde the magnitude of anemia in school-age children is unknown. The study aimed to assess the prevalence of anemia and associated factors among children in Cape Verde. The data are ...

  10. Study of the stability of natural convection in partially enclosed vertical annular space

    International Nuclear Information System (INIS)

    Njamkepo, S.N.

    1983-11-01

    This paper presents the study of the bidimensional-tridimensional flow transition, solving a system of coupled equations, dynamic and thermic, with the finite element method. The study of the stability of the bidimensional flow shows: the stabilizing effect of a big space thickness-space height ratio; the destabilizing effect of the Grashof number (constant ratio) [fr

  11. Estabilidad Fisicoquímica y Funcional de Uchuva (Physalis peruviana L. Impregnada a Vacío con Calcio y Vitaminas B9, D y E, Durante el Almacenamiento Refrigerado / Phisicochemical and Functional Stability of Cape Gooseberry (Physalis peruviana L. Vacuu

    Directory of Open Access Journals (Sweden)

    Peña Correa Ruth Fabiola

    2013-08-01

    Full Text Available Resumen. Debido a la creciente demanda de alimentossaludables, la industria alimentaria está mejorando el valornutritivo de estos, modificando su composición nutricional.Las frutas tropicales son ampliamente aceptadas por losconsumidores y a la vez representan una alternativa ideal para la obtención de alimentos funcionales a través de la incorporación de vitaminas y minerales. El objetivo de este estudio fue evaluar, en el transcurso del tiempo, variaciones en las propiedades fisicoquímicas, el contenido de vitaminas (C, B9, D y E y calcio, y la capacidad antioxidante (Folin, DPPH• y ABTS•+, de un producto de uchuva mínimamente procesado, fortificado por la técnica de impregnación a vacío (IV. Los resultados indican que una porción de 200 g de uchuva fortificada aporta el 81,6%; 72,3%; 38,9% y 50,2% de los valores diarios de referencia (VDR respectivos de las vitaminas B9, C, D y E, y el 15,4% de los de calcio. Durante el almacenamiento se encontró disminución de la concentración de las vitaminas B9 y E. Un comportamiento similar al de la vitamina E se presentó en la capacidad antioxidante (CA medida en la fracción liposoluble. La incorporación de componentes fisiológicamente activos en el interior de la estructura de las uchuvas mediante la técnica de IV, le confieren a la fruta mejores propiedades antioxidantes yfuncionales respecto a las uchuvas frescas. / Abstract. Due to the increasing demand of healthy foods, the food industry is improving the nutritional value of these by changing their nutritional composition. Tropical fruits are widelyaccepted by consumers and are an ideal alternative for obtaining functional foods through the addition of vitamins and minerals. The aim of this study was to evaluate, over time, variations in the physicochemical properties, vitamins (C, B9, D and E and calcium, and the antioxidant capacity (Folin, DPPH• and ABTS•+, in a cape gooseberry minimally processed product, fortified by

  12. Urban Ecology in Cape Town: South African Comparisons and Reflections

    Directory of Open Access Journals (Sweden)

    Sarel S. Cilliers

    2012-09-01

    Full Text Available Little urban ecological research has been done in South Africa. The papers in the Ecology and Society special feature Urban Ecological and Social-Ecological Research in the City of Cape Town make, therefore, an important contribution to the development of urban ecology locally and globally. Different approaches have been used in the study of urban ecology of different urban areas in South Africa. Cape Town is situated in a biodiversity hotspot and is the only South African city which includes a national park. As a result the urban ecological studies were mainly driven by urban nature conservation concerns. In other cities such as Durban, open space planning and environmental management were the major issues which focused ecological studies on urban areas whereas other studies of urban areas in the Eastern Cape and North-West provinces included private and public open spaces and man-made habitats. We reflect on the Cape Town studies in a South African context and highlight conservation of biodiversity, protection of ecosystem services, management of control measures, and the conflict between humans and nature. A brief synthesis has also been given of South African urban ecological research in general.

  13. [Gnathosonics study of the occlusal stability of orthodontic patients].

    Science.gov (United States)

    Jiang, Ruo-Ping; Tyson, Kenneth W

    2008-02-18

    To analysis the stability of the occlusion before and after the orthodontic treatment by gnathosonics; To evaluate the reliability of the stethoscope method by comparing the subjective(stethoscopy) and objective(digital occlusal sound recording) methods of checking the occlusal sound. Sixty-four new patients with malocclusion were selected as the before treatment group, these patients were not subject to any previous orthodontic treatment, facial surgery or injury; the treatment complete group included 15 patients who were just debonded the fixed appliance. Both stethoscope and digital occlusal sound recording were used to evaluate the occlusal sound. The occlusal stability before and after orthodontic treatment was compared depending on the results from the objective examination. The stability of the occlusion between different types of malocclusion before treatment was compared also. The veracity and reliability of the stethoscope method were analysis using the objective method as the golden standard. (1) 43.75%(28/64) of the 64 new patients showed unstable occlusal sound. ANOVA test showed that there were no statistically significant differences between the unstable rates in different type of malocclusion. (2) 40% (6/15) of the 15 treatment complete patients had unstable occlusions. (3) There were no statistically significant differences between the unstable rate pre- and post-treatment. (4) The veracity of the stethoscopes was 81.01% (64/79). (5) Kappa test showed that the stethoscopes and the digital recording method were consistent; the Kappa value was 0.488, Pocclusion rate between the two groups, and between the different types of malocclusion before treatment. (2) Using stethoscopes method to check the occlusal sound is reliable. The veracity could be improved significantly with increased experiences.

  14. Study of the stability of n-diamond

    International Nuclear Information System (INIS)

    Wen Bin; Li Tingju; Dong Chuang; Zhang Xingguo; Yao Shan; Cao Zhiqiang; Wang Dehe; Ji Shouhua; Jin Junze

    2004-01-01

    Powders of n-diamond can be synthesized by pyrogenation of carbon black and nanometre-sized iron catalyst at atmospheric pressure and at a temperature of 1100 deg. C. The stability of n-diamond was investigated with x-ray diffraction, thermal gravimetric analysis and differential thermal analysis. The results indicated that n-diamond was a metastable phase: it can decompose at room temperature slowly. Thermal decomposition of n-diamond begins at 150 deg. C and is complete at 400 deg. C, and the decomposition of n-diamond was an exothermic reaction

  15. Hypertension care at a Cape Town community health centre | Lunt ...

    African Journals Online (AJOL)

    Objectives. To describe the demographic profile of hypertensive patients and the quality of care for hypertension at a Cape Town community health centre (CHC). Design. Prospective, descriptive study. Setting and subjects. Medium-sized CHC, attended by 1098 hypertensive patients during a 1-year period from 1 January ...

  16. Temporality and Patterns of ART Adherence in the Western Cape

    African Journals Online (AJOL)

    In an ethnographic study conducted over thirty months in South Africa's Western Cape Province ending in 2012, we explored ART adherence amongst almost 200 patients attending three clinics. This setting contained significant political, structural, economic and socio cultural barriers to the uptake of, and adherence to, ...

  17. Tuberculosis drug resistance in the Western Cape | Weyer | South ...

    African Journals Online (AJOL)

    Objectives: Drug resistance is a serious problem in the treatment of tuberculosis and a threat to successful tuberculosis control programmes. Local health workers have expressed concern that the increasing tuberculosis epidemic in the Western Cape is partly attributable to drug resistance. The aim of this study was to ...

  18. Estimating Cape hare occupancy and abundance in southern ...

    African Journals Online (AJOL)

    This study outlines the importance of integrating spotlighting data and occupancy modelling to estimate the spatial occupancy, abundance and habitat preferences of Cape hares Lepus capensis in southern Tunisia. Exploring the spatial distribution pattern of this species is problematic because of its nocturnal and secretive ...

  19. Carriage of Haemophilus influenzae in Cape Town children ...

    African Journals Online (AJOL)

    Little is known about the epideIDiology of Haemophilus influenzae infections in South Africa. This study was designed to determine the prevalence, serotype distribution, antimicrobial susceptibility pattern and effect of age and hospitalisation on the carriage of H. influenzae in 322 Cape Town children. The overall and type b ...

  20. Role of Stakeholders at Cape Coast PPAG Youth Centre ...

    African Journals Online (AJOL)

    The study investigated whether the activities or the roles performed by the various stakeholders at the Cape Coast Planned Parenthood Association of Ghana (PPAG) youth centre impacted positively on the youth behaviour and performance at the centre. The sample comprised 22 teachers, 50 parents and 3 social welfare ...

  1. Patterns and drivers of marine bioinvasions in eight Western Cape ...

    African Journals Online (AJOL)

    In South Africa, fouling is the dominant vector of marine invasions, being responsible for 48% of the 86 alien introductions that are known. This study aimed to document alien species in fouling assemblages in eight Western Cape harbours and to assess patterns and potential drivers of these invasions. In each harbour, 10 ...

  2. Reproductive biology of the cape serotine bat, Eptesicus capensis in ...

    African Journals Online (AJOL)

    The reproductive biology of the Cape serotine bat, Eptesicus capensis, was investigated histologically. The study was based on 67 specimens collected over a six-year period. This species is seasonally monoestrous, normally giving birth to twins during November. Spermatogenesis peaks during autumn (March-May) when ...

  3. The epidemiology of hypertension family practice in Cape Town ...

    African Journals Online (AJOL)

    A prevalence study of hypertension in 8 family practices in low socio-economic areas of Cape Town examined 1046 patients over the age of 15 years. The crude prevalence rate of hypertension was 20,26%. There was no significant sex difference. Systolic pressure, diastolic pressure and hypertensive status increased with ...

  4. Party identification and service delivery protests in the Eastern Cape ...

    African Journals Online (AJOL)

    Service delivery protests against municipalities in South Africa have become common. This article discusses the relationship between party identification and these protests. It presents an in-depth analysis of two qualitative case studies: one in the Eastern Cape Province, where protests have mainly been about the shortage ...

  5. Anthropometric profile of the coloured population of the Cape ...

    African Journals Online (AJOL)

    Study of a sample of 976 randomly selected coloured persons 15 - 64 years of age living in the Cape Peninsula included measurement of height, weight and mid-arm circumference and calculation of the body mass index (BMI). The mean height of the men was 167,6 cm and that of the women 156 cm. Mean weight, BMI ...

  6. Contributions to the biology of the Cape gurnard, Trigla capensis ...

    African Journals Online (AJOL)

    Study of otoliths of the Cape gurnard,Trigla capensis, has established that the rings are annular. An opaque zone is formed from February to Jury and a hyaline zone during the spawning season from August to March. Females grow faster than males. The Von Bertalanffy growth equation of the females was found to be.

  7. The Tijaniyya Tariqa in Cape Town | Lliteras | Journal for Islamic ...

    African Journals Online (AJOL)

    This study finds that the spiritual praxis of the Tijaniyya profoundly influences the social behaviour of its followers, as is exemplified by its impact on issues of race relations and identity in South Africa. The findings suggest that the Tijaniyya tariqa in Cape Town offers the unique opportunity to challenge racism and prejudice, ...

  8. Energetic Requirements for Growth and Maintenance of the Cape ...

    African Journals Online (AJOL)

    Energetic requirements for growth and maintenance of the Cape gannet (Sula capensis) were studied by hand-rearing captive chicks and keeping juveniles in captivity at constant mass. Daily gain in mass was linear until 60 days of age; after 82 days the chicks lost mass prior to attaining fledging age (97 days).

  9. Diet of Cape fur seals Arctocephalus pusillus pusillus at three ...

    African Journals Online (AJOL)

    Scat analysis was used to assess temporal variability in the diet composition of Cape fur seals Arctocephalus pusillus pusillus from three breeding colonies in Namibia (January 1994 to April 2002). The diet displayed significant inter- and intra-annual variation in composition at each of the study colonies. The diet was not ...

  10. Distribution of blood lead levels in schoolchildren in selected cape ...

    African Journals Online (AJOL)

    Objective. To determine blood lead levels among children attending schools in selected Cape Peninsula suburbs, and to assess the impact of a reduction in the lead content of petrol. Design. A cross-sectional analytical study of children's blood lead levels and associated risk factors. Setting. Selected inner city, suburban, ...

  11. Parechinus angulosus Leske in False B-ay, Cape

    African Journals Online (AJOL)

    The cooperation of officers of the Seaweed. Laboratory, Sea Fisheries Branch, during diving field work was very much appreciated. Thanks to Mr R.H. Simons for identifying algal material. Without the patience and com- petent boat-handling of Mr J. Allen of the Zoology De- partment of the University of Cape Town, this study ...

  12. Empowering families by engaging and relating Murri way: a grounded theory study of the implementation of the Cape York Baby Basket program.

    Science.gov (United States)

    McCalman, Janya; Searles, Andrew; Bainbridge, Roxanne; Ham, Rachael; Mein, Jacki; Neville, Johanna; Campbell, Sandra; Tsey, Komla

    2015-05-21

    Evaluating program outcomes without considering how the program was implemented can cause misunderstandings and inefficiencies when initiating program improvements. In conjunction with a program evaluation, reported elsewhere, this paper theorises the process of implementing an Indigenous Australian maternal and child health program. The Baby Basket program was developed in 2009 for the remote Cape York region and aimed to improve the attendance and engagement of Indigenous women at antenatal and postnatal clinics through providing three baskets of maternal and baby goods and associated health education. Constructivist grounded theory methods were used to generate and analyse data from qualitative interviews and focus groups with Indigenous women who received the baskets, their extended family members, and healthcare workers who delivered them. Data was coded in NVivo with concepts iteratively compared until higher order constructs and their relationships could be modelled to explain the common purpose for participants, the process involved in achieving that purpose, key strategies, conditions and outcomes. Theoretical terms are italicised. Program implementation entailed empowering families through a process of engaging and relating Murri (Queensland Indigenous) way. Key influencing conditions of the social environment were the remoteness of communities, keeping up with demand, families' knowledge, skills and roles and organisational service approaches and capacities. Engaging and relating Murri way occurred through four strategies: connecting through practical support, creating a culturally safe practice, becoming informed and informing others, and linking at the clinic. These strategies resulted in women and families taking responsibility for health through making healthy choices, becoming empowered health consumers and advocating for community changes. The theoretical model was applied to improve and revise Baby Basket program implementation, including

  13. Study of global stability of tall buildings with prestressed slabs

    Directory of Open Access Journals (Sweden)

    L. A. Feitosa

    Full Text Available The use of prestressed concrete flat slabs in buildings has been increasing in recent years in the Brazilian market. Since the implementation of tall and slender buildings a trend in civil engineering and architecture fields, arises from the use of prestressed slabs a difficulty in ensuring the overall stability of a building without beams. In order to evaluate the efficiency of the main bracing systems used in this type of building, namely pillars in formed "U" in elevator shafts and stairs, and pillars in which the lengths are significantly larger than their widths, was elaborated a computational models of fictional buildings, which were processed and analyzed using the software CAD/TQS. From the variation of parameters such as: geometry of the pillars, thick slabs, characteristic strength of the concrete, reduceofthe coefficient of inertia for consideration of non-linearities of the physical elements, stiffness of the connections between slabs and pillars, among others, to analyze the influence of these variables on the overall stability of the building from the facing of instability parameter Gama Z, under Brazilian standard NBR 6118, in addition to performing the processing of building using the P-Delta iterative calculation method for the same purpose.

  14. Stability and Change in Work Values: A Meta-Analysis of Longitudinal Studies

    Science.gov (United States)

    Jin, Jing; Rounds, James

    2012-01-01

    A meta-analysis of longitudinal studies was conducted to investigate stability and change in work values across the life span. Both rank-order stability and mean-level change were investigated using an integrative classification for intrinsic, extrinsic, social and status work values (Ross, Schwartz, & Surkis, 1999). Results of rank-order…

  15. Theoretical studies on the stability of the salts formed by DTDO with ...

    Indian Academy of Sciences (India)

    Toggle navigation. Logo of the Indian Academy of Sciences. Indian Academy of Sciences. Home · About ... Home; Journals; Journal of Chemical Sciences; Volume 127; Issue 4. Theoretical studies on the stability of the salts formed by ... Keywords. Salts; conformations; stability; density functional theory, energetic materials.

  16. A method for studying stability domains in physical models

    Science.gov (United States)

    Gallas, Jason A. C.

    1994-10-01

    We present a method for investigating the simultaneous movement of all zeros of equations of motions defined by discrete mappings. The method is used to show that knowledge of the interplay of all zeros is of fundamental importance for establishing periodicities and relative stability properties of the various possible physical solutions. The method is also used (i) to show that the Frontière set of Fatou is defined primarily by zeros of functions leading to an entire invariant limiting function which underlies every dynamical system, (ii) to identify cyclotomic polynomials as components of the limiting function obtained for a parameter value supporting a particular superstable orbit of the quadratic map, (iii) to describe highly symmetric periodic cycles embedded in these components, and (iv) to provide an unified picture about which mathematical objects form basin boundaries of dynamical systems in general: the closure of all zeros not belonging to “stable” orbits.

  17. SAXS Study of Sterically Stabilized Lipid Nanocarriers Functionalized by DNA

    Science.gov (United States)

    Angelov, Borislav; Angelova, Angelina; Filippov, Sergey; Karlsson, Göran; Terrill, Nick; Lesieur, Sylviane; Štěpánek, Petr

    2012-03-01

    The structure of novel spontaneously self-assembled plasmid DNA/lipid complexes is investigated by means of synchrotron radiation small-angle X-ray scattering (SAXS) and Cryo-TEM imaging. Liquid crystalline (LC) hydrated lipid systems are prepared using the non-ionic lipids monoolein and DOPE-PEG2000 and the cationic amphiphile CTAB. The employed plasmid DNA (pDNA) is encoding for the human protein brain-derived neurotrophic factor (BDNF). A coexistence of nanoparticulate objects with different LC inner organizations is established. A transition from bicontinuous membrane sponges, cubosome intermediates and unilamelar liposomes to multilamellar vesicles, functionalized by pDNA, is favoured upon binding and compaction of pBDNF onto the cationic PEGylated lipid nanocarriers. The obtained sterically stabilized multicompartment nanoobjects, with confined supercoiled plasmid DNA (pBDNF), are important in the context of multicompartment lipid nanocarriers of interest for gene therapy of neurodegenerative diseases.

  18. SAXS Study of Sterically Stabilized Lipid Nanocarriers Functionalized by DNA

    International Nuclear Information System (INIS)

    Angelov, Borislav; Filippov, Sergey; Štepánek, Petr; Angelova, Angelina; Lesieur, Sylviane; Karlsson, Göran; Terrill, Nick

    2012-01-01

    The structure of novel spontaneously self-assembled plasmid DNA/lipid complexes is investigated by means of synchrotron radiation small-angle X-ray scattering (SAXS) and Cryo-TEM imaging. Liquid crystalline (LC) hydrated lipid systems are prepared using the non-ionic lipids monoolein and DOPE-PEG 2000 and the cationic amphiphile CTAB. The employed plasmid DNA (pDNA) is encoding for the human protein brain-derived neurotrophic factor (BDNF). A coexistence of nanoparticulate objects with different LC inner organizations is established. A transition from bicontinuous membrane sponges, cubosome intermediates and unilamelar liposomes to multilamellar vesicles, functionalized by pDNA, is favoured upon binding and compaction of pBDNF onto the cationic PEGylated lipid nanocarriers. The obtained sterically stabilized multicompartment nanoobjects, with confined supercoiled plasmid DNA (pBDNF), are important in the context of multicompartment lipid nanocarriers of interest for gene therapy of neurodegenerative diseases.

  19. Risk of breast cancer following exposure to tetrachloroethylene-contaminated drinking water in Cape Cod, Massachusetts: reanalysis of a case-control study using a modified exposure assessment

    Directory of Open Access Journals (Sweden)

    Webster Thomas F

    2011-05-01

    Full Text Available Abstract Background Tetrachloroethylene (PCE is an important occupational chemical used in metal degreasing and drycleaning and a prevalent drinking water contaminant. Exposure often occurs with other chemicals but it occurred alone in a pattern that reduced the likelihood of confounding in a unique scenario on Cape Cod, Massachusetts. We previously found a small to moderate increased risk of breast cancer among women with the highest exposures using a simple exposure model. We have taken advantage of technical improvements in publically available software to incorporate a more sophisticated determination of water flow and direction to see if previous results were robust to more accurate exposure assessment. Methods The current analysis used PCE exposure estimates generated with the addition of water distribution modeling software (EPANET 2.0 to test model assumptions, compare exposure distributions to prior methods, and re-examine the risk of breast cancer. In addition, we applied data smoothing to examine nonlinear relationships between breast cancer and exposure. We also compared a set of measured PCE concentrations in water samples collected in 1980 to modeled estimates. Results Thirty-nine percent of individuals considered unexposed in prior epidemiological analyses were considered exposed using the current method, but mostly at low exposure levels. As a result, the exposure distribution was shifted downward resulting in a lower value for the 90th percentile, the definition of "high exposure" in prior analyses. The current analyses confirmed a modest increase in the risk of breast cancer for women with high PCE exposure levels defined by either the 90th percentile (adjusted ORs 1.0-1.5 for 0-19 year latency assumptions or smoothing analysis cut point (adjusted ORs 1.3-2.0 for 0-15 year latency assumptions. Current exposure estimates had a higher correlation with PCE concentrations in water samples (Spearman correlation coefficient = 0.65, p

  20. Modeling vegetation community responses to sea-level rise on Barrier Island systems: A case study on the Cape Canaveral Barrier Island complex, Florida, USA.

    Directory of Open Access Journals (Sweden)

    Tammy E Foster

    Full Text Available Society needs information about how vegetation communities in coastal regions will be impacted by hydrologic changes associated with climate change, particularly sea level rise. Due to anthropogenic influences which have significantly decreased natural coastal vegetation communities, it is important for us to understand how remaining natural communities will respond to sea level rise. The Cape Canaveral Barrier Island complex (CCBIC on the east central coast of Florida is within one of the most biologically diverse estuarine systems in North America and has the largest number of threatened and endangered species on federal property in the contiguous United States. The high level of biodiversity is susceptible to sea level rise. Our objective was to model how vegetation communities along a gradient ranging from hydric to upland xeric on CCBIC will respond to three sea level rise scenarios (0.2 m, 0.4 m, and 1.2 m. We used a probabilistic model of the current relationship between elevation and vegetation community to determine the impact sea level rise would have on these communities. Our model correctly predicted the current proportions of vegetation communities on CCBIC based on elevation. Under all sea level rise scenarios the model predicted decreases in mesic and xeric communities, with the greatest losses occurring in the most xeric communities. Increases in total area of salt marsh were predicted with a 0.2 and 0.4 m rise in sea level. With a 1.2 m rise in sea level approximately half of CCBIC's land area was predicted to transition to open water. On the remaining land, the proportions of most of the vegetation communities were predicted to remain similar to that of current proportions, but there was a decrease in proportion of the most xeric community (oak scrub and an increase in the most hydric community (salt marsh. Our approach provides a first approximation of the impacts of sea level rise on terrestrial vegetation communities

  1. Modeling vegetation community responses to sea-level rise on Barrier Island systems: A case study on the Cape Canaveral Barrier Island complex, Florida, USA.

    Science.gov (United States)

    Foster, Tammy E; Stolen, Eric D; Hall, Carlton R; Schaub, Ronald; Duncan, Brean W; Hunt, Danny K; Drese, John H

    2017-01-01

    Society needs information about how vegetation communities in coastal regions will be impacted by hydrologic changes associated with climate change, particularly sea level rise. Due to anthropogenic influences which have significantly decreased natural coastal vegetation communities, it is important for us to understand how remaining natural communities will respond to sea level rise. The Cape Canaveral Barrier Island complex (CCBIC) on the east central coast of Florida is within one of the most biologically diverse estuarine systems in North America and has the largest number of threatened and endangered species on federal property in the contiguous United States. The high level of biodiversity is susceptible to sea level rise. Our objective was to model how vegetation communities along a gradient ranging from hydric to upland xeric on CCBIC will respond to three sea level rise scenarios (0.2 m, 0.4 m, and 1.2 m). We used a probabilistic model of the current relationship between elevation and vegetation community to determine the impact sea level rise would have on these communities. Our model correctly predicted the current proportions of vegetation communities on CCBIC based on elevation. Under all sea level rise scenarios the model predicted decreases in mesic and xeric communities, with the greatest losses occurring in the most xeric communities. Increases in total area of salt marsh were predicted with a 0.2 and 0.4 m rise in sea level. With a 1.2 m rise in sea level approximately half of CCBIC's land area was predicted to transition to open water. On the remaining land, the proportions of most of the vegetation communities were predicted to remain similar to that of current proportions, but there was a decrease in proportion of the most xeric community (oak scrub) and an increase in the most hydric community (salt marsh). Our approach provides a first approximation of the impacts of sea level rise on terrestrial vegetation communities, including important

  2. A pilot study of core stability and athletic performance: is there a relationship?

    Science.gov (United States)

    Sharrock, Chris; Cropper, Jarrod; Mostad, Joel; Johnson, Matt; Malone, Terry

    2011-06-01

    Correlation study To objectively evaluate the relationship between core stability and athletic performance measures in male and female collegiate athletes. The relationship between core stability and athletic performance has yet to be quantified in the available literature. The current literature does not demonstrate whether or not core strength relates to functional performance. Questions remain regarding the most important components of core stability, the role of sport specificity, and the measurement of core stability in relation to athletic performance. A sample of 35 volunteer student athletes from Asbury College (NAIA Division II) provided informed consent. Participants performed a series of five tests: double leg lowering (core stability test), the forty yard dash, the T-test, vertical jump, and a medicine ball throw. Participants performed three trials of each test in a randomized order. Correlations between the core stability test and each of the other four performance tests were determined using a General Linear Model. Medicine ball throw negatively correlated to the core stability test (r -0.389, p=0.023). Participants that performed better on the core stability test had a stronger negative correlation to the medicine ball throw (r =-0.527). Gender was the most strongly correlated variable to core strength, males with a mean measurement of double leg lowering of 47.43 degrees compared to females having a mean of 54.75 degrees. There appears to be a link between a core stability test and athletic performance tests; however, more research is needed to provide a definitive answer on the nature of this relationship. Ideally, specific performance tests will be able to better define and to examine relationships to core stability. Future studies should also seek to determine if there are specific sub-categories of core stability which are most important to allow for optimal training and performance for individual sports.

  3. AIDS-Related Endemic Mycoses in Western Cape, South Africa, and Clinical Mimics: A Cross-Sectional Study of Adults With Advanced HIV and Recent-Onset, Widespread Skin Lesions

    Science.gov (United States)

    Kenyon, Chris; Lehloenya, Rannakoe; Claasens, Saskya; Spengane, Zandile; Prozesky, Hans; Burton, Rosie; Parker, Arifa; Wasserman, Sean; Meintjes, Graeme; Mendelson, Marc; Taljaard, Jantjie; Schneider, Johann W; Beylis, Natalie; Maloba, Bonnie; Govender, Nelesh P; Colebunders, Robert; Dlamini, Sipho

    2017-01-01

    Abstract Background Skin lesions are common in advanced HIV infection and are sometimes caused by serious diseases like systemic mycoses (SM). AIDS-related SM endemic to Western Cape, South Africa, include emergomycosis (formerly disseminated emmonsiosis), histoplasmosis, and sporotrichosis. We previously reported that 95% of patients with AIDS-related emergomycosis had skin lesions, although these were frequently overlooked or misdiagnosed clinically. Prospective studies are needed to characterize skin lesions of SM in South Africa and to help distinguish these from common HIV-related dermatoses. Methods We prospectively enrolled HIV-infected adult patients living in Western Cape, South Africa, with CD4 counts ≤100 cells/μL and widespread skin lesions present ≤6 months that were deemed clinically compatible with SM. We obtained skin biopsies for histopathology and fungal culture and collected epidemiological and clinical data. Results Of 34 patients enrolled and in whom a diagnosis could be made, 25 had proven SM: 14 had emergomycosis, and 3 each had histoplasmosis and sporotrichosis; for 5 additional patients, the fungal species could not be identified. Antiretroviral therapy (ART) had been initiated in the preceding 4 weeks for 11/25 (44%) patients with SM (vs no patients without SM). Plaques and scale crust occurred more frequently in patients with SM (96% vs 25%, P = .0002; and 67% vs 13%, P = .01, respectively). Conclusions Recent ART initiation and presence of plaques or scale crust should make clinicians consider SM in patients with advanced HIV infection in this geographic area. Clinical overlap between SM and other dermatoses makes early skin biopsy critical for timely diagnosis and treatment. PMID:29164168

  4. Continuous Flow of Upper Labrador Sea Water around Cape Hatteras.

    Science.gov (United States)

    Andres, Magdalena; Muglia, Mike; Bahr, Frank; Bane, John

    2018-03-14

    Six velocity sections straddling Cape Hatteras show a deep counterflow rounding the Cape wedged beneath the poleward flowing Gulf Stream and the continental slope. This counterflow is likely the upper part of the equatorward-flowing Deep Western Boundary Current (DWBC). Hydrographic data suggest that the equatorward flow sampled by the shipboard 38 kHz ADCP comprises the Upper Labrador Sea Water (ULSW) layer and top of the Classical Labrador Sea Water (CLSW) layer. Continuous DWBC flow around the Cape implied by the closely-spaced velocity sections here is also corroborated by the trajectory of an Argo float. These findings contrast with previous studies based on floats and tracers in which the lightest DWBC constituents did not follow the boundary to cross under the Gulf Stream at Cape Hatteras but were diverted into the interior as the DWBC encountered the Gulf Stream in the crossover region. Additionally, our six quasi-synoptic velocity sections confirm that the Gulf Stream intensified markedly at that time as it approached the separation point and flowed into deeper waters. Downstream increases were observed not only in the poleward transport across the sections but also in the current's maximum speed.

  5. Tecer sobe no ranking da Capes

    Directory of Open Access Journals (Sweden)

    José Aparecido

    2013-11-01

    Full Text Available Surpresa ainda maior foi verificar que prosseguimos no rumo da consolidação, crescendo no ranking – chegando a B3 em alguns campos, como pode ser visto no portal de buscas do Qualis Capes http://qualis.capes.gov.br/webqualis/principal.seamhttp://qualis.capes.gov, que apresenta nossa classificação abaixo:   B3 ADMINISTRAÇÃO, CIÊNCIAS CONTÁBEIS E TURISMO B4 CIÊNCIAS SOCIAIS APLICADAS I B4 EDUCAÇÃO B4 INTERDISCIPLINAR B5 DIREITO B5 HISTÓRIA C CIÊNCIA DA COMPUTAÇÃO

  6. IN VIVO STUDIES AND STABILITY STUDY OF CLADOPHORA GLOMERATA EXTRACT AS A COSMETIC ACTIVE INGREDIENT.

    Science.gov (United States)

    Fabrowska, Joanna; Kapuscinska, Alicja; Leska, Boguslawa; Feliksik-Skrobich, Katarzyna; Nowak, Izabela

    2017-03-01

    Marine algae are widely used as cosmetics raw materials. Likewise, freshwater alga Cladophora glomerata may be a good source of fatty acids and others bioactive agents. The aims of this study was to find out if the addition of the extract from the freshwater C. glonerata affects the stability of prepared cosmetic emulsions and to investigate in vivo effects of the extract in cosmetic formulations on hydration and elasticity of human skin. Extract from the freshwater C. glonierata was obtained using supercritical fluid extraction (SFE). Two forms of O/W emulsions were prepared: placebo and emulsion containing 0.5% of Cladophora SFE extract. The stability of obtained emulsions was investigated by using Turbiscan Lab Expert. Emulsions were applied by .volunteers daily. Corneometer was used to evaluate skin hydration and cutometer to examine skin elasticity. Measurements were conducted at reference point (week 0) and after 1st, 2nd, 3rd and 4th week of application. The addition of Cladophora extract insignificantly affected stability of the emulsion. The extract from C. glomerata in the emulsion influenced the improvement of both skin hydration and its elasticity. Thus, freshwater C. glonierata extract prepared via SFE method may be considered as an effective cosmetic raw material used as a moisturizing and firming agent.

  7. Implant Stability Changes during Early Phase of Healing:A Prospective Cohort Study

    Directory of Open Access Journals (Sweden)

    A. Mesgarzadeh

    2009-06-01

    Full Text Available Objective: To assess the stability changes as a reflection of early healing around roughened-surface implants in human by resonance frequency analysis (RFA.Materials and Methods: One hundred and fifty one ITI SLA implants were placed in either maxilla or mandible of 68 patients. Bone type was classified into 4 groups according to Lekholm and Zarb index. RFA was used for direct implant stability measurement on theday of implant placement, and at 14, 30 and 60 days after placement. Student t-test and ANOVA served for statistical analysis.Results: No early failure occurred. The highest and lowest primary stability was measured in type 1 and type 4 bone, respectively. Implant stability increased over time in types 3 and 4 bone but continuously decreased in type 1 bone during the first 60 days of healing.In type 2 a small decrease in stability was observed until 30 days, and after that the stability increased. The difference between implant stability in type 2 and type 4 bone at eachtime point was highly significant (P0.05. The effect of implant length and diameter on stability at different times was tested with mixed model ANOVA, and no significant difference among groups was observed (P>0.05Conclusion: The present study demonstrated that the pattern of stability changes was different among various bone types. With regard to primary stability and pattern of stability changes in types 2 and 3 bone, immediate and early loading protocols can be recommended in these two bone types, respectively.

  8. Thermal stability studies of diamond-like carbon films

    Energy Technology Data Exchange (ETDEWEB)

    Parmeter, J.E.; Tallant, D.R.; Siegal, M.P.

    1994-04-01

    Thin films of amorphous carbon/hydrogen, also known as diamond-like carbon or DLC, are of interest as an economical alternative to diamond in a variety of coatings applications. We have investigated the thermal stability of DLC films deposited onto tungsten and aluminum substrates via plasma CVD of methane. These films contain approximately 40 atom % hydrogen, and based on Auger spectra the carbon in the films is estimated to be 60% sp{sup 3} hybridized and 40% sp{sup 2} hybridized. Thermal desorption, Auger, and Raman measurements all indicate that the DLC films are stable to 250--300C. Between 300 and 500C, thermal evolution of hydrogen from the films is accompanied by the conversion of carbon from sp{sup 3} to sp{sup 2} hybridization, and Raman spectra indicate the conversion of the overall film structure from DLC to micro-crystalline graphite or so called ``glassy`` carbon. These results suggest that DLC of this type is potentially useful for applications in which the temperature does not exceed 250C.

  9. Synthesis and Stability of Iron Nanoparticles for Lunar Environment Studies

    Science.gov (United States)

    Hung, Ching-cheh; McNatt, Jeremiah

    2009-01-01

    Simulant of lunar dust is needed when researching the lunar environment. However, unlike the true lunar dust, today s simulants do not contain nanophase iron. Two different processes have been developed to fabricate nanophase iron to be used as part of the lunar dust simulant: (1) Sequentially treating a mixture of ferric chloride, fluorinated carbon, and soda lime glass beads at about 300 C in nitrogen, at room temperature in air, and then at 1050 C in nitrogen. The product includes glass beads that are grey in color, can be attracted by a magnet, and contain alpha-iron nanoparticles (which seem to slowly lose their lattice structure in ambient air during a period of 12 months). This product may have some similarity to the lunar glassy regolith that contains Fe(sup 0). (2) Heating a mixture of carbon black and a lunar simulant (a mixed metal oxide that includes iron oxide) at 1050 C in nitrogen. This process simulates lunar dust reaction to the carbon in a micrometeorite at the time of impact. The product contains a chemically modified simulant that can be attracted by a magnet and has a surface layer whose iron concentration increased during the reaction. The iron was found to be alpha-iron and Fe3O4 nanoparticles, which appear to grow after the fabrication process, but stabilizes after 6 months of ambient air storage.

  10. [Study on relationship between emotional stability in flight and nerve system excitability].

    Science.gov (United States)

    Liu, Fang; Huang, Wei-fen; Jing, Xiao-lu; Zhang, Ping

    2003-06-01

    To study the related factors of emotional stability in flight. Based on the operable definition of emotional stability in flight and the related literature review, 63 experienced pilots and flight coaches were investigated and the other-rating questionnaire of emotional stability in flight was established. To test the senior nerve system, Uchida Kraeplin (UK) test was administrated on 153 19-21 years old male student pilots of the second grade in the department of flight technique in China Civil Aviation College, who were selected through 13 h flight, 35 h solo flight, and acted as the standardization group. In the end, the correlation was explored between the testing results and their emotional behavioral characteristics in flight. Significant positive correlation was found between emotional feature indexes of emotional stability in flight and excitability in UK test. The excitability in UK test are good predictors for emotional stability in flight.

  11. Stabilization of liquid low-level and mixed wastes: a treatability study

    International Nuclear Information System (INIS)

    Carson, S.; Cheng, Yu-Cheng; Yellowhorse, L.; Peterson, P.

    1996-01-01

    A treatability study has been conducted on liquid low-level and mixed wastes using the stabilization agents Aquaset, Aquaset II, Aquaset II-H, Petroset, Petroset-H, and Petroset and Petroset II. A total of 40 different waste types with activities ranging from 10 -14 to 10 -4 curies/ml have been stabilized. Reported data for each waste include its chemical and radiological composition and the optimum composition or range of compositions (weight of agent/volume of waste) for each stabilization agent used. All wastes were successfully stabilized with one or more of the stabilization agents and all final waste forms passed the Paint Filter Liquids Test (EPA Method 9095)

  12. Stabilization of liquid low-level and mixed wastes: a treatability study

    Energy Technology Data Exchange (ETDEWEB)

    Carson, S.; Cheng, Yu-Cheng; Yellowhorse, L.; Peterson, P.

    1996-02-01

    A treatability study has been conducted on liquid low-level and mixed wastes using the stabilization agents Aquaset, Aquaset II, Aquaset II-H, Petroset, Petroset-H, and Petroset and Petroset II. A total of 40 different waste types with activities ranging from 10{sup {minus}14} to 10{sup {minus}4} curies/ml have been stabilized. Reported data for each waste include its chemical and radiological composition and the optimum composition or range of compositions (weight of agent/volume of waste) for each stabilization agent used. All wastes were successfully stabilized with one or more of the stabilization agents and all final waste forms passed the Paint Filter Liquids Test (EPA Method 9095).

  13. Real time and accelerated stability studies of Tetanus toxoid manufactured in public sector facilities of Pakistan.

    Science.gov (United States)

    Parveen, Ghazala; Hussain, Shahzad; Malik, Farnaz; Begum, Anwar; Mahmood, Sidra; Raza, Naeem

    2013-11-01

    Tetanus is an acute illness represented by comprehensive increased inflexibility and spastic spasms of skeletal muscles. The poor quality tetanus toxoid vaccine can raise the prevalence of neonatal tetanus. WHO has taken numerous steps to assist national regulatory authorities and vaccine manufacturers to ensure its quality and efficacy. It has formulated international principles for stability evaluation of each vaccine, which are available in the form of recommendations and guidelines. The aim of present study was to ensure the stability of tetanus vaccines produced by National Institute of Health, Islamabad, Pakistan by employing standardized methods to ensure constancy of tetanus toxoid at elevated temperature, if during storage/transportation cold chain may not be maintained in hot weather. A total of three batches filled during full-scale production were tested. All Stability studies determination were performed on final products stored at 2-8°C and elevated temperatures in conformance with the ICH Guideline of Stability Testing of Biological Products. These studies gave comparison between real time shelf-life stability and accelerated stability studies. The findings indicate long﷓term thermo stability and prove that this tetanus vaccine can remain efficient under setting of routine use when suggested measures for storage and handling are followed in true spirit.

  14. A study of helicopter stability and control including blade dynamics

    Science.gov (United States)

    Zhao, Xin; Curtiss, H. C., Jr.

    1988-01-01

    A linearized model of rotorcraft dynamics has been developed through the use of symbolic automatic equation generating techniques. The dynamic model has been formulated in a unique way such that it can be used to analyze a variety of rotor/body coupling problems including a rotor mounted on a flexible shaft with a number of modes as well as free-flight stability and control characteristics. Direct comparison of the time response to longitudinal, lateral and directional control inputs at various trim conditions shows that the linear model yields good to very good correlation with flight test. In particular it is shown that a dynamic inflow model is essential to obtain good time response correlation, especially for the hover trim condition. It also is shown that the main rotor wake interaction with the tail rotor and fixed tail surfaces is a significant contributor to the response at translational flight trim conditions. A relatively simple model for the downwash and sidewash at the tail surfaces based on flat vortex wake theory is shown to produce good agreement. Then, the influence of rotor flap and lag dynamics on automatic control systems feedback gain limitations is investigated with the model. It is shown that the blade dynamics, especially lagging dynamics, can severly limit the useable values of the feedback gain for simple feedback control and that multivariable optimal control theory is a powerful tool to design high gain augmentation control system. The frequency-shaped optimal control design can offer much better flight dynamic characteristics and a stable margin for the feedback system without need to model the lagging dynamics.

  15. Study of structures and stability in nitrogen plasma jet

    International Nuclear Information System (INIS)

    Tiwari, Nirupama; Meher, K.C.; Ghorui, Srikumar

    2015-01-01

    Stability of a dc non-transferred arc plasma jet and its internal structures are important for any application related to material processing like plasma spraying, nano synthesis etc. Plasma jet fluctuation and structure formation inside arc plasma jets occur due to reasons like arc root rotation, power supply fluctuation, air entrainment and interaction between electromagnetic and fluid dynamic body forces. Isolated temperature islands originated through such interactions affects particle trajectory, physical processes and process chemistry in a significant manner. In this paper, plasma jet images are recorded at frame rate 7000 FPS for argon and nitrogen plasma. Images are synchronized with voltage signal using camera trigger signal as a trigger to the digital storage oscilloscope. In the experiment, gas flow rate is varied from 10 lpm to 30 lpm in step of 5 lpm keeping torch power constant. All parameter of the camera (exposure time, aperture, focal length) are kept fixed throughout. It has been observed that the luminous length of the plasma jet decreases with increase in gas flow rate for nitrogen, while the reverse happens for argon. It is also observed that while the plasma jet remains fairly steady for low flow rate, variety of different interesting structures are observed inside the plasma jet at higher flow rates. The intensity variation and intensity contours inside the plasma jet are probed using image analysis software. It has been observed that these structures are relatively independent of the arc voltage but highly dependent on gas flow rate and torch power. Reasons for observed behavior are investigated. As thermal and chemical processes are highly dependent on temperature, observed isolated temperature zones inside the plasma jet are of great importance from application point of view. Plasma blob movement observed inside the jet is used for a rough estimate of the plasma jet velocity. (author)

  16. Studies of solid liner stability in electromagnetic implosions

    International Nuclear Information System (INIS)

    Atchison, W.L.; Faehl, R.J.; Rienovsky, R.E.; Morgan, D.

    1998-01-01

    simulations and analysis will be presented of both sets of experiments and interpretations of the effect of conductivity on liner stability will be given

  17. Stability and change in alcohol habits of different socio-demographic subgroups--a cohort study.

    Science.gov (United States)

    Sydén, Lovisa; Wennberg, Peter; Forsell, Yvonne; Romelsjö, Anders

    2014-05-29

    Stability in alcohol habits varies over time and in subgroups, but there are few longitudinal studies assessing stability in alcohol habits by socio-demographic subgroups and potential predictors of stability and change. The aim was to study stability and change in alcohol habits by sex, age, and socio-economic position (SEP). Data derived from two longitudinal population based studies in Sweden; the PART study comprising 19 457 individuals aged 20-64 years in 1998-2000, and the Stockholm Public Health Cohort (SPHC) with 50 067 individuals aged 18-84 years in 2002. Both cohorts were followed-up twice; PART 2000-2003 and 2010, and SPHC 2007 and 2010. Alcohol habits were measured with the Alcohol Use Disorders Identification Test (AUDIT), and with normal weekly alcohol consumption (NWAC). Stability in alcohol habits was measured with intraclass correlation. Odds ratios were estimated in multinomial logistic regression analysis to predict stability in alcohol habits. For the two drinking measures there were no consistent patterns of stability in alcohol habits by sex or educational level. The stability was higher for older age groups and self-employed women. To be a man aged 30-39 at baseline predicted both increase and decrease in alcohol habits. The findings illustrate higher stability in alcohol habits with increasing age and among self-employed women with risky alcohol habits. To be a man and the age 30-39 predicted change in alcohol habits. No conclusive pattern of socio-economic position as predictor of change in alcohol habits was found and other studies of potential predictors seem warranted.

  18. NAMMA PRAIA CAPE VERDE RADIOSONDE V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The NAMMA Praia Cape Verde Radiosonde data used Sippican MarkIIa DGPS (LOS) radiosondes, which were launched in support of NASA African Monsoon Multidisciplinary...

  19. Gaze stabilization reflexes in the mouse: New tools to study vision and sensorimotor

    NARCIS (Netherlands)

    B. van Alphen (Bart)

    2010-01-01

    markdownabstract__abstract__ Gaze stabilization reflexes are a popular model system in neuroscience for connecting neurophysiology and behavior as well as studying the neural correlates of behavioral plasticity. These compensatory eye movements are one of the simplest motor behaviors,

  20. The stability study of myristyl dimethyl amine oxide as an amphoteric ...

    African Journals Online (AJOL)

    The stability study of myristyl dimethyl amine oxide as an amphoteric surfactant in strong oxidant media containing 5 % m/m sodium hypochlorite through measurement of decomposing rate using high performance liquid chromatography and two phase titration.

  1. Study on mechanism for amorphous drug stabilization using gelucire 50/13.

    Science.gov (United States)

    Shimpi, Shamkant Laxman; Mahadik, Kakasaheb Ramoo; Paradkar, Anant Raghunath

    2009-09-01

    Methods of preparation and application of amorphous form are well established but it is equally important to note that devitrification of amorphous drugs has limited their applications. Present study was performed to investigate mechanism for amorphous drug stabilization using Gelucire in comparison with polyvinylpyrrolidone (PVP). Etoricoxib and celecoxib were taken as model drugs for this study, as etoricoxib has only proton accepting site for hydrogen bonding in comparison with celecoxib, which has both proton accepting and donating site. Solid dispersion of celecoxib with polyvinylpyrrolidone and Gelucire was prepared by spray drying and melt-granulation technique respectively. X-ray powder diffractometry and differential scanning calorimetry were used to study the physical state of the drug. Dissolution studies were performed to differentiate dissolution performance. Stability study samples were evaluated for physical state of the drug and dissolution performance. An IR study in correlation with molecular modeling was carried out to study the mechanism for stabilization. Dissolution of melt-granulation of amorphous celecoxib was improved significantly as compared to amorphous celecoxib and Celecoxib-PVP solid dispersion. Melt-granulation with lipid seemed to be more dominant than amorphization of drug for improving dissolution. Stability data revealed that PVP was significantly advantageous for amorphous form stabilization whereas Gelucire failed in case of Celecoxib. In contrast to this, our previous study revealed the stabilization ability of Gelucire for amorphous etoricoxib. Molecular modeling and IR studies revealed that H-bonding was predominant mechanism for stabilization. Out of two proposed mechanism for amorphous drug stabilization by lipids, H-bonding ability is more dominant than immobilization of molecule in lipid matrix.

  2. The Cape doctor 1807-1910: perspectives.

    Science.gov (United States)

    Phillips, Howard

    2004-01-01

    This chapter contrasts the Cape doctor in 1807 and in 1910, and finds that, in a whole variety of ways, the differences between the two were not of degree but of kind. Underlying this sea-change was the germ revolution of the late Victorian era, which transformed the Cape doctor out of all recognition, thereby laying important foundations for the development of the twentieth-century South African doctor.

  3. Study of stability of a bandpass sigma delta modulator with sinusoidal input

    Energy Technology Data Exchange (ETDEWEB)

    Iu, Herbert H.C. [School of Electrical, Electronic and Computer Engineering, University of Western Australia, 35 Stirling Highway, Crawley (Australia)]. E-mail: herbert@ee.uwa.edu.au

    2007-07-15

    Bandpass sigma delta modulators (SDMs) have applications in areas such as digital radio demodulation. Stability issues of bandpass SDMs have been widely studied. Usually, zero or step inputs are considered. In this paper, we study the stability and non-linear phenomena of a bandpass SDM with sinusoidal input. In particular, the effects of the amplitude and frequency of the sinusoidal input signal will be investigated.

  4. Quality control and stability study of 100 mg/ml paracetamol oral drops

    International Nuclear Information System (INIS)

    Garcia Penna, Caridad M.; Montes de Oca Porto, Yanet; Salomon Izquierdo, Suslebys

    2013-01-01

    Paracetamol is an effective analgesic and antipyretic drug of the non-steroidal anti-inflammatory drug group. Paracetamol oral drops are indicated for use in infant population aged up to 5 years to relieve fever, headache, toothache and symptomatic relief of common cold. To validate two analytical methods for the quality control and the stability study and to study the stability of 100 mg/ml Paracetamol oral drops made in Cuba

  5. Vegetative and Productive Behaviors of Cape Gooseberry (Physalis peruviana L.), Grown by Direct Sowing Outside Under Conditions of Bulgaria

    OpenAIRE

    PANAYOTOV, Nikolay; POPOVA, Ani

    2015-01-01

    Cape gooseberry is a new crop for Bulgaria. Therefore, the establishment of appropriate technology is important. The main aim of this study was to evaluate the effect of different date of direct sowing outside under Bulgarian condition on the morphological development and on the productivity of cape gooseberry. The experiments were carried out with two varieties cape gooseberry - first Bulgarian variety Plovdiv and Columbian ecotype Obrazec 1 in region of Plovdiv, Bulgaria. Three dates of dir...

  6. Cervical stability training with and without core stability training for patients with cervical disc herniation: A randomized, single-blind study.

    Science.gov (United States)

    Buyukturan, B; Guclu-Gunduz, A; Buyukturan, O; Dadali, Y; Bilgin, S; Kurt, E E

    2017-11-01

    This study aims at evaluating and comparing the effects of cervical stability training to combined cervical and core stability training in patients with neck pain and cervical disc herniation. Fifty patients with neck pain and cervical disc herniation were included in the study, randomly divided into two groups as cervical stability and cervical-core stability. Training was applied three times a week in three phases, and lasted for a total duration of 8 weeks. Pain, activation and static endurance of deep cervical flexor muscles, static endurance of neck muscles, cross-sectional diameter of M. Longus Colli, static endurance of trunk muscles, disability and kinesiophobia were assessed. Pain, activation and static endurance of deep cervical flexors, static endurance of neck muscles, cross-sectional diameter of M. Longus Colli, static endurance of trunk muscles, disability and kinesiophobia improved in both groups following the training sessions (p < 0.05). Comparison of the effectiveness of these two training methods revealed that the cervical stability group produced a greater increase in the right transverse diameter of M. Longus Colli (p < 0.05). However, static endurance of trunk muscles and kinesiophobia displayed better improvement in the cervical-core stability group (p < 0.05). Cervical stability training provided benefit to patients with cervical disc herniation. The addition of core stability training did not provide any additional significant benefit. Further research is required to investigate the efficacy of combining other techniques with cervical stability training in patients with cervical disc herniation. Both cervical stability training and its combination with core stability training were significantly and similarly effective on neck pain and neck muscle endurance in patients with cervical disc herniation. © 2017 European Pain Federation - EFIC®.

  7. I-V Performance and stability study of dyes for luminescent plate concentrators

    Energy Technology Data Exchange (ETDEWEB)

    Slooff, L.H.; Kinderman, R.; Burgers, A.R.; Van Roosmalen, J.A.M. [ECN Solar Energy, Petten (Netherlands); Buechtemann, A.; Danz, R. [Fraunhofer Institute for Applied Polymer Research, Geiselbergstr. 69, D-14476 Golm (Germany)

    2007-08-15

    In this paper, both the performance and stability of luminescent flat plate concentrator (LFPC) plates in combination with mc-Si photovoltaic cells are studied. It is shown that the electrical current of a silicon solar cell attached to the luminescent plate is improved by a factor 1.5 using a LFPC containing a single dye. It is also shown that most of the dyes are not stable in the polymer plates that are currently used. Screening of the stability of several other dyes indicates that the stability is strongly dependent on the type of dye and the polymer matrix, e.g., additives or the monomer residues.

  8. Analytical and numerical studies of sawtooth stabilization with on-axis ICRH on Tore Supra

    International Nuclear Information System (INIS)

    Zabiego, M.; Basiuk, V.; Becoulet, A.; Garbet, X.; Saoutic, B.; White, R.B.; Wu, Y.

    1995-01-01

    Sawtooth stabilization has recently been achieved with on-axis ICRH on Tore Supra. Analytic and numerical tools have been developed that allow analysis of these data, with the emphasis on the energetic-particle contribution. The latter is calculated on the basis of an original expression for the hot-ion distribution function, mostly-passing, deduced from theoretical and experimental ICRH studies, and compared to the usual mostly-trapped model. Both models account for stabilization, but for different reasons: with the mostly-passing distribution, stabilization is essentially driven by barely-passing hot ions. (author) 9 refs.; 2 figs

  9. Tourist Profile and Destination Brand Perception: The Case of Cape Town, South Africa

    Directory of Open Access Journals (Sweden)

    Ikechukwu O. Ezeuduji

    2016-08-01

    Full Text Available Tourists pay for destination brands. This study checked for the relationships between tourists’ profile and how they perceived the destination brand of Cape Town. A questionnaire survey of 220 tourists visiting Cape Town was done. This study found that repeat visit, age of tourist, length of stay, and tourist origin, have significant influences on how tourists visiting Cape Town perceived the destination. The top three destination attributes of Cape Town (cognitive images, which enhance visitor experience satisfaction are (1 the overall level of service quality at facilities in Cape Town, (2 the city being one of the best places the tourists have visited, and (3 the destination’s good value for money. The top three emotional valuations of destination attributes (affective images which enhance visitor experience satisfaction in Cape Town include (1 memorable visit, (2 valuable visit, and (3 friendly and hospitable population. It is therefore recommended that tourism businesses in Cape Town develop relationship marketing tools to attract and retain its tourists segments of loyal, advanced in age, long-staying and domestic tourists. Results from this research could be compared with related findings in the international arena and have related implications, especially for developing economies

  10. 'Cape capture': Geologic data and modeling results suggest the holocene loss of a Carolina Cape

    Science.gov (United States)

    Thieler, E.R.; Ashton, A.D.

    2011-01-01

    For more than a century, the origin and evolution of the set of cuspate forelands known as the Carolina Capes-Hatteras, Lookout, Fear, and Romain-off the eastern coast of the United States have been discussed and debated. The consensus conceptual model is not only that these capes existed through much or all of the Holocene transgression, but also that their number has not changed. Here we describe bathymetric, lithologic, seismic, and chronologic data that suggest another cape may have existed between Capes Hatteras and Lookout during the early to middle Holocene. This cape likely formed at the distal end of the Neuse-Tar-Pamlico fiuvial system during the early Holocene transgression, when this portion of the shelf was fiooded ca. 9 cal (calibrated) kyr B.P., and was probably abandoned by ca. 4 cal kyr B.P., when the shoreline attained its present general configuration. Previously proposed mechanisms for cape formation suggest that the large-scale, rhythmic pattern of the Carolina Capes arose from a hydrodynamic template or the preexisting geologic framework. Numerical modeling, however, suggests that the number and spacing of capes can be dynamic, and that a coast can self-organize in response to a high-angle-wave instability in shoreline shape. In shoreline evolution model simulations, smaller cuspate forelands are subsumed by larger neighbors over millennial time scales through a process of 'cape capture.' The suggested former cape in Raleigh Bay represents the first interpreted geological evidence of dynamic abandonment suggested by the self-organization hypothesis. Cape capture may be a widespread process in coastal environments with large-scale rhythmic shoreline features; its preservation in the sedimentary record will vary according to geologic setting, physical processes, and sea-level history. ?? 2011 Geological Society of America.

  11. Color Stability of Teeth Restored with Biodentine: A 6-month In Vitro Study.

    Science.gov (United States)

    Vallés, Marta; Roig, Miguel; Duran-Sindreu, Fernando; Martínez, Syani; Mercadé, Montserrat

    2015-07-01

    White mineral trioxide aggregate (WMTA) has been reported to cause dental discoloration. A previous study on the color stability of 5 calcium silicate-based materials investigated the color stability of Biodentine (Septodont, Saint-Maur-des-Fossés, France) in different experimental environments; however, no data are available on the color stability of teeth restored with Biodentine. In this study, we assessed the color stability under artificial light of ex vivo human teeth restored coronally with WMTA or Biodentine. Cavities were prepared on coronal tooth specimens and restored with WMTA + composite (n = 16), Biodentine + composite (n = 16), or composite alone (control, n = 3). Color was assessed spectrophotometrically at 6 time points (initial, 1 week, 2 weeks, 1 month, 3 months, and 6 months), and color difference values were calculated. Statistical analysis was performed using analysis of variance and the Fisher least significant difference test for which P Biodentine and control groups showed color stability and were not significantly different from one another. Teeth treated with WMTA exhibited discoloration, whereas those treated with Biodentine maintained color stability throughout the study. However, further in vivo studies are necessary to corroborate these results. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. Empirical Study of the Stability of Biodiesel and Biodiesel Blends: Milestone Report

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, R. L.; Westbrook, S. R.

    2007-05-01

    The objective of this work was to develop a database that supports specific proposals for a stability test and specification for biodiesel and biodiesel blends. B100 samples from 19 biodiesel producers were obtained in December of 2005 and January of 2006 and tested for stability. Eight of these samples were then selected for additional study, including long-term storage tests and blending at 5% and 20% with a number of ultra-low sulfur diesel fuels.

  13. A review of Khoi-San and Cape Dutch medical ethnobotany.

    Science.gov (United States)

    van Wyk, B-E

    2008-10-28

    ETHNOPHARMACOLOGICAL CONTEXT: Cape herbal medicine as a distinct and unique healing system is conceptualized for the first time, together with a first compilation of the authentic materia medica of the system. The early literature on Khoikhoi (Hottentot), San (Bushman) and Cape Dutch medicinal plants and medical practices is reviewed, with a focus on the Cape Floristic Region (from Namaqualand to the Eastern Cape). To avoid recent additions and modern cultural influences in the results, the date of publication of the last volume of Marloth's Flora of South Africa (1932) was chosen as a cut-off date. The recorded Cape materia medica (up to 1932) is briefly summarized, giving the scientific names, vernacular names (in Afrikaans or Khoi-San/Nama) and main uses. It comprises about 170 items and includes mainly indigenous and endemic plant species, some exotic (garden) plants, and a few other items (fungi, seaweeds, lichens, hyraceum and natural potassium nitrate). Most of the plants (and hyraceum) are still widely used today, especially in rural areas. The combination of unique cultural practices and a diverse, highly endemic flora has led to the development of a distinct herbal healing system, here called Cape herbal medicine, but hitherto rather vaguely and inaccurately referred to as Khoi-San medicine, Cape Dutch medicine or boererate (farm remedies). The data allows for a more informed consideration of indigenous knowledge and intellectual property rights associated with particular plants (e.g. Hoodia and Pelargonium). It also offers opportunities for linking modern ethnobotanical field studies with historical data.

  14. Validation of the Spanish adaptation of the Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V).

    Science.gov (United States)

    Núñez-Batalla, Faustino; Morato-Galán, Marta; García-López, Isabel; Ávila-Menéndez, Arántzazu

    2015-01-01

    The Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) was developed.to promote a standardised approach to evaluating and documenting auditory perceptual judgments of vocal quality. This tool was originally developed in English language and its Spanish version is still inexistent. The aim of this study was to develop a Spanish adaptation of CAPE-V and to examine the reliability and empirical validity of this Spanish version. To adapt the CAPE-V protocol to the Spanish language, we proposed 6 phrases phonetically designed according to the CAPE-V requirements. Prospective instrument validation was performed. The validity of the Spanish version of the CAPE-V was examined in 4 ways: intra-rater reliability, inter-rater reliability and CAPE-V versus GRABS judgments. Inter-rater reliability coefficients for the CAPE-V ranged from 0.93 for overall severity to 0.54 for intensity; intra-rater reliability ranged from 0.98 for overall severity to 0.85 for intensity. The comparison of judgments between GRABS and CAPE-V ranged from 0.86 for overall severity to 0.61 for breathiness. The present study supports the use of the Spanish version of CAPE-V because of its validity and reliability. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

  15. Regulation of stability studies to enhance the efficiency of drug registrations to regulatory authorities

    Directory of Open Access Journals (Sweden)

    Mohammad Sajjad Khan

    2015-01-01

    Full Text Available Stability testing is an important tool to assess the quality of drug substances and products which may vary with time under influence of variety of factors such as temperature, humidity, and light. Stability studies of drugs are designed according to the climatic zones to establish a retest period for active drug substance or a shelf life for the finished product as well as to recommend the storage conditions. The strict regulatory requirements on designing, performing evaluating stability study to claim the expiry date, and shelf life of drug products are based on a series of regulatory requirements and advisory guidelines that have been developed by regulatory authorities of US, Europe, and Japan which; were harmonized through the development of the International Conference on Harmonization (ICH procedures. To assess the stability of drug substances and products, the design and conduct of stability studies, defining relevant thresholds for impurities testing is required with a current good manufacturing practice-based risk management approach to achieve a robust stability of pharmaceutical dosage forms. There are relevant requirements that cover new drug substances and products as well as new dosage forms containing existing active ingredients and vice versa.

  16. Exploration of Deaf People’s Health Information Sources and Techniques for Information Delivery in Cape Town: A Qualitative Study for the Design and Development of a Mobile Health App

    Science.gov (United States)

    Glaser, Meryl; Tucker, William David; Diehl, Jan Carel

    2016-01-01

    Background Many cultural and linguistic Deaf people in South Africa face disparity when accessing health information because of social and language barriers. The number of certified South African Sign Language interpreters (SASLIs) is also insufficient to meet the demand of the Deaf population in the country. Our research team, in collaboration with the Deaf communities in Cape Town, devised a mobile health app called SignSupport to bridge the communication gaps in health care contexts. We consequently plan to extend our work with a Health Knowledge Transfer System (HKTS) to provide Deaf people with accessible, understandable, and accurate health information. We conducted an explorative study to prepare the groundwork for the design and development of the system. Objectives To investigate the current modes of health information distributed to Deaf people in Cape Town, identify the health information sources Deaf people prefer and their reasons, and define effective techniques for delivering understandable information to generate the groundwork for the mobile health app development with and for Deaf people. Methods A qualitative methodology using semistructured interviews with sensitizing tools was used in a community-based codesign setting. A total of 23 Deaf people and 10 health professionals participated in this study. Inductive and deductive coding was used for the analysis. Results Deaf people currently have access to 4 modes of health information distribution through: Deaf and other relevant organizations, hearing health professionals, personal interactions, and the mass media. Their preferred and accessible sources are those delivering information in signed language and with communication techniques that match Deaf people’s communication needs. Accessible and accurate health information can be delivered to Deaf people by 3 effective techniques: using signed language including its dialects, through health drama with its combined techniques, and accompanying

  17. Study of nuclear power plant stability. Trip criteria

    International Nuclear Information System (INIS)

    Beato Castro, D.; Iturbe Uriarte, R.; Wilhelmi Ayza, J.R.

    1993-01-01

    The influence that nuclear power plants and high voltage power systems have on each other when confronted by disturbances in the offsite network may lead, due to dynamic effects, to plant trip. It is therefore necessary to study the disturbances in the network and the effects on plant equipment by means of dynamic simulations which evaluate the unit protection system and the auxiliary services so as to obtain maximum unit availability without jeopardizing its safety. These studies can be conducted since there are models and software tools capable of simulating dynamic behaviour of the electric system, including the excitation systems and specific speed governors obtainment of valid. (author)

  18. Theoretical study of fractal growth and stability on surface

    DEFF Research Database (Denmark)

    Dick, Veronika V.; Solov'yov, Ilia; Solov'yov, Andrey V.

    2009-01-01

    We perform a theoretical study of the fractal growing process on surface by using the deposition, diffusion, aggregation method. We present a detailed analysis of the post-growth processes occurring in a nanofractal on surface. For this study we developed a method which describes the internal...... dynamics of particles in a fractal and accounts for their diffusion and detachment. We demonstrate that these kinetic processes are responsible for the formation of the final shape of the islands on surface after the post-growth relaxation....

  19. Study on the development and stability of perovskite solar cells

    Science.gov (United States)

    Xing, Shucheng

    2017-08-01

    Recently, the development of perovskite solar cells has aroused the concern of the majority of scholars, the current photoelectric conversion efficiency has reached 21%. So the thorough study of the principle of perovskite type solar cells will make better the use of its special performance. But so far, perovskite type solar cells still have many unstable factors. This paper first discusses the predecessor of perovskite solar cells, dye-sensitized batteries, and then study the working principle of the former, followed by the perovskite-type thermal instability and light instability to be discussed, at last talks about the current Major issues perovskite materials are facing and make a summary.

  20. Studies on genetics, stability and possible mechanism of ...

    Indian Academy of Sciences (India)

    Navya

    All of these examples support our study that selection of P. solenopsis with deltamethrin has a great impact on development of insecticide resistance. Development of very high resistance in P. solenopsis might be due to excessive use of deltamethrin by farmers in the field for the control of this pest in cotton growing areas of ...

  1. Stability studies and degradation kinetics of some commercially ...

    African Journals Online (AJOL)

    The present study was undertaken to investigate the effect of temperature on the degradation of metronidazole suspensions commercially available in Nigeria. Six different brands of metronidazole suspension, coded as MTZ A to MTZ F, were evaluated for their active contents using microbiological assay method. They were ...

  2. Studies on genetics, stability and possible mechanism of ...

    Indian Academy of Sciences (India)

    ace of a new mealy bug, Phenacoccus gossypiphilous to the eco- nomic crops of Southern Asia, p. 30. Abstr. XI Int. Symp. on. Scale Insect Studies (ISSIS), 24–27, Oeiras, Portugal. Abbas N., Khan H. A. A. and Shad S. A. 2014 Cross-resistance, genetics, and realized heritability of resistance to fipronil in the house fly, Musca ...

  3. Study of Stability of Rotational Motion of Spacecraft with Canonical Variables

    Directory of Open Access Journals (Sweden)

    William Reis Silva

    2012-01-01

    Full Text Available This work aims to analyze the stability of the rotational motion of artificial satellites in circular orbit with the influence of gravity gradient torque, using the Andoyer variables. The used method in this paper to analyze stability is the Kovalev-Savchenko theorem. This method requires the reduction of the Hamiltonian in its normal form up to fourth order by means of canonical transformations around equilibrium points. The coefficients of the normal Hamiltonian are indispensable in the study of nonlinear stability of its equilibrium points according to the three established conditions in the theorem. Some physical and orbital data of real satellites were used in the numerical simulations. In comparison with previous work, the results show a greater number of equilibrium points and an optimization in the algorithm to determine the normal form and stability analysis. The results of this paper can directly contribute in maintaining the attitude of artificial satellites.

  4. Status of a study of stabilization and fine positioning of CLIC quadrupoles to the nanometre level

    CERN Document Server

    Artoos, K; Esposito, M; Fernandez Carmona, P; Guinchard, M; Hauviller, C; Janssens, S; Kuzmin, A; Leuxe, R; Moron Ballester, R

    2011-01-01

    Mechanical stability to the nanometre and below is required for the Compact Linear Collider (CLIC) quadrupoles to frequencies as low as 1 Hz. An active stabilization and positioning system based on very stiff piezo electric actuators and inertial reference masses is under study for the Main Beam Quadrupoles (MBQ). The stiff support was selected for robustness against direct forces and for the option of incrementally repositioning the magnet with nanometre resolution. The technical feasibility was demonstrated by a representative test mass being stabilized and repositioned to the required level in the vertical and lateral direction. Technical issues were identified and the development programme of the support, sensors, and controller was continued to increase the performance, integrate the system in the overall controller, adapt to the accelerator environment, and reduce costs. The improvements are implemented in models, test benches, and design of the first stabilized prototype CLIC magnet. The characterizati...

  5. Synthesis and formulation studies of griseofulvin analogues with improved solubility and metabolic stability

    DEFF Research Database (Denmark)

    Petersen, Asger Bjørn; Andersen, Nikolaj Sten; Konotop, Gleb

    2017-01-01

    potency in vitro. Analogue 2 was also shown to retard tumor growth through inhibition of centrosomal clustering in murine xenograft models of colon cancer and multiple myeloma. However, similar to griseofulvin, compound 2 exhibited poor metabolic stability and aqueous solubility. In order to improve...... the poor pharmacokinetic properties, 11 griseofulvin analogues were synthesized and evaluated for biological activity and physiological stabilities including SGF, plasma, and metabolic stability. Finally, the most promising compounds were investigated in respect to thermodynamic solubility and formulation...... studies. The 2'-benzylamine analogue 10 proved to be the most promising compound with low μM in vitro anticancer potency, a 200-fold increase in PBS solubility over compound 2, and with improved metabolic stability. Furthermore, this analogue proved compatible with formulations suitable for both oral...

  6. The stabilizing effect of streaks on Tollmien-Schlichting and oblique waves: A parametric study

    Science.gov (United States)

    Bagheri, Shervin; Hanifi, Ardeshir

    2007-07-01

    The stabilizing effect of finite amplitude streaks on the linear growth of unstable perturbations [Tollmien-Schlichting (TS) and oblique waves] is numerically investigated by means of the nonlinear parabolized stability equations. We have found that for stabilization of a TS-wave, there exists an "optimal" spanwise spacing of the streaks. These streaks reach their maximum amplitudes close to the first neutral point of the TS-wave and induce the largest distortion of the mean flow in the unstable region of the TS-wave. For such a distribution, the required streak amplitude for complete stabilization of a given TS-wave is considerably lower than for β =0.45, which is the optimal for streak growth and used in previous studies. We have also observed a damping effect of streaks on the growth rate of oblique waves in Blasius boundary layer and for TS-waves in Falkner-Skan boundary layers.

  7. Fundamental Studies of Fluid Mechanics: Stability in Porous Media

    Energy Technology Data Exchange (ETDEWEB)

    Homsy, George M. [Univ. of California, Santa Barbara, CA (United States). Department of Mechanical and Environmental Engineering

    2014-02-12

    We summarize our research results in three main areas: coating flows; electrohydrodynamics of drops; and wetting and spreading of drops. Experimental, computational and analytical methods are used to address a variety of issues. Coating flow studies include the effect of roughness, surfactants, and adsorbed particles on the dynamics of dip-coating. Electrohydrodynamic studies include drop deformation in uniform electric fields, shape distortion due to charge convection in sedimenting drops, and driving chaotic advection by either an electric field inclined to the direction of drop motion or time-periodic changes in the direction of the electric field. Heat and mass transport from chaotically mixed droplets exhibit unexpected and remarkable increases in the rates of transport. Finally, we develop an analytical solution to the problem of a static droplet, and use numerical techniques to predict its migration due to surface tension gradients.

  8. Lifetime of Bentonites study: hydrothermal stability of saponites; Estudio de longevidad en bentonitas: estabilidad hidrotermal de saponitas

    Energy Technology Data Exchange (ETDEWEB)

    Leguey, S.; Cuevas, J.; Garralon, A. [Universidad Autonoma de Madrid, Facultad de Ciencias, Departamento de Quimica Agricola, Geologia y Geoquimica, Madrid (Spain)

    1996-10-01

    The report studies the lifetime of bentonite and the hydrothermal stability of saponites. The testing comprised determination of physical and chemical properties of clays, the stability of the mineral porosity, lifetime and the wall of clay.

  9. Comparative study of gum arabic and PVP as stabilizing agents for synthesis of gold nanoparticles

    International Nuclear Information System (INIS)

    Silva, Andressa A.; Leal, Jessica; Geraldes, Adriana N.; Lugao, Ademar B.

    2015-01-01

    Use Colloidal metallic nanoparticles such as gold nanoparticles have received a great attention, due in part to their specific properties and potential applications. Control of size and uniformity of nanoparticles is important to prevent aggregation. High-molecular-weight polymers were used as stabilizer agents. Natural polymers, such as gum Arabic, are used as stabilizer because of capping nanoparticles behavior and present advantages such as solubility, non- toxicity and its compatibility for pharmaceutical and biomedical applications. Previous studies showed that the hydrophilic group of Poly(vinyl pyrrolidone) (PVP) caused repulsion on gold nanoparticles surface because steric interactions with polymer, for this reason this kind of polymers could be used as stabilizer agent. The aim of this work is to study the synthesis and stabilization of gold nanoparticles with PVP and gum Arabic using gamma radiation. The results obtained by samples analysis using UV-Visible showed that the gamma irradiation doses influenced the nanoparticles formation by PVP but that is not the case with the GA, because for smaller quantity of Arabic gum in different doses produced and stabilized nanoparticles. The samples were observed for 20 days and showed stability. We have obtained preliminary results showed that the use of radiation is applicable to the formation of gold nanoparticles. (author)

  10. Comparative study of gum arabic and PVP as stabilizing agents for synthesis of gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Andressa A.; Leal, Jessica; Geraldes, Adriana N.; Lugao, Ademar B., E-mail: andressa_alvess@yahoo.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Use Colloidal metallic nanoparticles such as gold nanoparticles have received a great attention, due in part to their specific properties and potential applications. Control of size and uniformity of nanoparticles is important to prevent aggregation. High-molecular-weight polymers were used as stabilizer agents. Natural polymers, such as gum Arabic, are used as stabilizer because of capping nanoparticles behavior and present advantages such as solubility, non- toxicity and its compatibility for pharmaceutical and biomedical applications. Previous studies showed that the hydrophilic group of Poly(vinyl pyrrolidone) (PVP) caused repulsion on gold nanoparticles surface because steric interactions with polymer, for this reason this kind of polymers could be used as stabilizer agent. The aim of this work is to study the synthesis and stabilization of gold nanoparticles with PVP and gum Arabic using gamma radiation. The results obtained by samples analysis using UV-Visible showed that the gamma irradiation doses influenced the nanoparticles formation by PVP but that is not the case with the GA, because for smaller quantity of Arabic gum in different doses produced and stabilized nanoparticles. The samples were observed for 20 days and showed stability. We have obtained preliminary results showed that the use of radiation is applicable to the formation of gold nanoparticles. (author)

  11. Librarian documents stabilization: experimental studies and implementation perspectives

    Directory of Open Access Journals (Sweden)

    Zatoka L.

    2016-01-01

    Full Text Available The article reviews various methods of documents protection against the destroying effect of micromycetes. The methods considered have been in use since the third decade of the 20th century. The authors provide information on the search of new disinfectants from the list recommended by the Ministry of Health of Ukraine. In particular, these include nipagin and a new product "Valeus-D" (analog of the investigated earlier Polidez. The received results of study of minimal concentrations of Valeus-D disinfectant alcohol and water solutions having effect on microscopic fungi are analyzed. Data on the influence of nipagin, "Valeus-D" and 70% ethanol on resistance to fungi, chemical and physicomechanical characteristics of model samples of four types of paper (rag, typographical, offset, newsprint are compared. The experiments’ results indicate, that 1% nipagin, 2% and 4% "Valeus-D"(pH 9 render the highest resistance to fungi. It is revealed, that 70% ethyl alcohol and 1% nipagin had the least influence on the physicomechanical properties of model samples of paper. Accentuated is the need to continue pilot studies of the use of other modern effective disinfectants and other types of paper

  12. Molecular biological study on genetic stability of the genome

    International Nuclear Information System (INIS)

    Hori, Tada-aki; Takahashi, Ei-ichi; Tsuji, Hideo; Tsuji, Satsuki

    1989-01-01

    A population cytogenetic study has been performed in 1022 healthy subjects and 547 cancer patients to determine baseline frequencies of autosomal rate fragile sites. Out of 17 rare autosomal fragile sites defined in HBM9 (1985), the following six were detected: fra(2)(q11), fra(10)(q25), fra(11)(q13), fra(11)(q23), fra(16)(q22) and fra(17)(q12). Other three new fragile sites were also detected: fra(8)(q24.1), fra(11)(q15.1) and fra(16)(p12.1). They were all distamycin A-inducible and located at the junctions of G/R-bands. The incidence of these autosomal fragile sites was 5% in both healthy subjects and cancer patients. Distamycin A-induced fragile sites may play a role in the etiology of leukemia, myeloproliferative disorders, and gynecological tumors. The present study also examined the mechanism of fragile X expression associated with fragile X syndrome in thymidine-prototrophic and auxotrophic human-mouse somatic cell hybrids. In these hybrid cells, both low and high thymidylate stresses were found to be effective in inducing fragile X expression, even in a hybrid clone that retained a fragile X chromosome as the only human chromosome. An addition of deoxycytidine completely abolished the effect of high thymidylate stress achieved by excess amounts of thymidine. It is concluded that the expression is an intrinsic property of the fragile X mutation resulting from chromosomal change in a special class of replicons with polypurine/polypyrimidine DNA sequence. (Namekawa, K)

  13. Renewable energy projects to electrify rural communities in Cape Verde

    International Nuclear Information System (INIS)

    Ranaboldo, Matteo; Lega, Bruno Domenech; Ferrenbach, David Vilar; Ferrer-Martí, Laia; Moreno, Rafael Pastor; García-Villoria, Alberto

    2014-01-01

    Highlights: • The design of 2 off-grid electrification projects in Cape Verde is developed. • Configurations with hybrid renewable energy systems and micro-grids are considered. • A detailed micro-scale wind resource assessment is carried out. • An optimization model is used in order to support the design. • The proposed system is economically beneficial in comparison with diesel generation. - Abstract: Even though Cape Verde has high wind and solar energy resources, the conventional strategy for increasing access to electricity in isolated rural areas is by centralized microgrids with diesel generators. In this study, the design of 2 off-grid electrification projects based on hybrid wind–photovoltaic systems in Cape Verde is developed and analyzed. The design considers some significant novelty features in comparison with previous studies. First a detailed wind resource assessment is carried out combining meso-scale wind climate data and a specialized micro-scale wind flow model. Then a mathematical model is used for the design of off-grid projects considering a combination of individual systems and microgrids. In this study, locations far from the demand points are also considered as possible generation points. Various design configurations are analyzed and compared. The proposed configurations exploit the highest wind potential areas and are economically beneficial in comparison with diesel generator systems

  14. Study of vibrations and stabilization of linear collider final doublets at the sub-nanometer scale

    International Nuclear Information System (INIS)

    Bolzon, B.

    2007-11-01

    CLIC is one of the current projects of high energy linear colliders. Vertical beam sizes of 0.7 nm at the time of the collision and fast ground motion of a few nanometers impose an active stabilization of the final doublets at a fifth of nanometer above 4 Hz. The majority of my work concerned vibrations and active stabilization study of cantilever and slim beams in order to be representative of the final doublets of CLIC. In a first part, measured performances of different types of vibration sensors associated to an appropriate instrumentation showed that accurate measurements of ground motion are possible from 0.1 Hz up to 2000 Hz on a quiet site. Also, electrochemical sensors answering a priori the specifications of CLIC can be incorporated in the active stabilization at a fifth of nanometer. In a second part, an experimental and numerical study of beam vibrations enabled to validate the efficiency of the numerical prediction incorporated then in the simulation of the active stabilization. Also, a study of the impact of ground motion and of acoustic noise on beam vibrations showed that an active stabilization is necessary at least up to 1000 Hz. In a third part, results on the active stabilization of a beam at its two first resonances are shown down to amplitudes of a tenth of nanometer above 4 Hz by using in parallel a commercial system performing passive and active stabilization of the clamping. The last part is related to a study of a support for the final doublets of a linear collider prototype in phase of finalization, the ATF2 prototype. This work showed that relative motion between this support and the ground is below imposed tolerances (6 nm above 0.1 Hz) with appropriate boundary conditions. (author)

  15. Scattering studies on cryoglobulins stability and aggregation properties

    Energy Technology Data Exchange (ETDEWEB)

    Bicev, R.N.; Oliveira, E.A.; Oliveira, C.L.P.; Brandao, H. [Universidade de Sao Paulo (USP), SP (Brazil); Andrade, L.E.C. [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil)

    2012-07-01

    Full text: Cryoglobulins are proteins of the immunoglobulin(Ig) type, which play an important role in infections, autoimmune diseases and neoplastic disorders[1]. When in abnormal concentrations in the blood, cryoglobulins can aggregate and precipitate at temperatures below 37 deg C, forming large complexes with dimensions in the range of 40 nm up to 1 {mu}m depending on the temperature, leading to damage of arteries and veins of small caliber. The objective of this study is to investigate the aggregation dynamics of cryoglobulin solutions through scattering techniques as SAXS (small angle X-Ray scattering). For the SAXS measures it was used the protein in aqueous and the system temperature was varied between 38:5 deg C and 4 deg C. The protein concentration was 10mg/mL.The GNOM [2] program was used for the first data analysis. This program performs the Fourier transform (IFT) of the scattering data, which provides the overall particle size, radius of gyration and some indications of the particle shape. The IFT analysis can be used to the so called ab initio modeling which provides a three-dimensional model for particle shape. This model was an attempt to obtain a real space representation for the particle system. Although it was possible to verify difference in the particle diameter for the different temperatures, the models provide a branched structure which can indicate polydispersity of shapes/sizes and also flexible structures. Interestingly, the construction of Kratky Plots, (I {center_dot} q{sup 2} vs q), which provide the compactness degree of a structure, indicated that the particles were highly flexible. Therefore another model procedure, which models the protein as polymer-like structure[3], have to be used. Using the recently developed Ensemble Optimization Method (EOM) [4] it was possible to obtain a very good fit for the experimental dataset, the distributions of radius of gyration and also three-dimensional representations of the possible

  16. Conopeptides from Cape Verde Conus crotchii

    Directory of Open Access Journals (Sweden)

    Agostinho Antunes

    2013-06-01

    Full Text Available Marine Cone snails of the genus Conus contain complex peptide toxins in their venom. Living in tropical habitats, they usually use the powerful venom for self-defense and prey capture. Here, we study Conus crotchii venom duct using a peptide mass-matching approach. The C. crotchii was collected on the Cape Verde archipelago in the Boa Vista Island. The venom was analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS. About 488 molecular masses between 700 Da and 3000 Da were searched bymatching with known peptide sequences from UniProtKB protein sequence database. Through this method we were able to identify 12 conopeptides. For validation we considered the error between the experimental molecular mass (monoisotopic and the calculated mass of less than 0.5 Da. All conopeptides detected belong to the A-, O1-, O2-, O3-, T- and D-superfamilies, which can block Ca2+ channels, inhibit K+ channels and act on nicotinic acetylcholine receptors (nAChRs. Only a few of the detected peptides have a 100% UniProtKB database similarity, suggesting that several of them could be newly discovered marine drugs.

  17. Implant stability during initiation and resolution of experimental periimplantitis: an experimental study in the dog.

    Science.gov (United States)

    Sennerby, Lars; Persson, Leif G; Berglundh, Tord; Wennerberg, Ann; Lindhe, Jan

    2005-01-01

    Histologic studies have demonstrated the possibility to reestablish direct bone-implant contacts after ligature-induced periimplantitis. The influence of the reosseointegration on the stability of implants is not known. The aim of the present investigation was to study bone tissue and associated implant stability alterations that occurred during induction and resolution of periimplantitis using resonance frequency analysis (RFA), radiography, and histology. Three implants with smooth (turned) or roughened (SLA) surfaces were placed in each side of the edentulous mandible of four dogs. Experimental periimplantitis was induced for 3 months. Five weeks later, the animals were treated with antibiotics and surgical therapy and were followed for another 6 months. Periapical radiographs and RFA were used to evaluate marginal bone levels and implant stability throughout the study period. After termination, the tissue-implant interface was evaluated by light microscopy in ground sections. There was a linear relationship between radiographic and RFA findings because continuous loss of marginal bone and a decrease in implant stability were observed for both implant surfaces during the periimplantitis period. Antibiotic treatment and surgical therapy resulted in some reosseointegration, which was more marked for the SLA surface. The resonance frequency values corresponded well to the histometric measurements because reosseointegration resulted in an increase in implant stability. The findings from the present study indicate a linear relationship between marginal bone level and resonance frequency value. It is suggested that the RFA technique is sensitive and may be used to detect even a minor change in the level of bone-implant contact.

  18. Parametric study of the stability properties of a thermo hydraulic channel coupled to punctual kinetics

    International Nuclear Information System (INIS)

    Cecenas F, M.; Campos G, R.M.

    2005-01-01

    The reason of decay is the indicator of stability usually used in the literature to evaluate stability of boiling water reactors, however, in the operation of this type of reactors is considered the length of boiling like an auxiliary parameter for the evaluation of stability. In this work its are studied the variation of these two indicators when modifying a given an operation parameter in a model of a thermo hydraulic channel coupled to punctual kinetics, maintaining all the other input constant variables. The parameters selected for study are the axial profile of power, the subcooling, the flow of coolant and the thermal power. The study is supplemented by means of real data of plant using the one Benchmark of Ringhals, and the results for the case of the ratio of decay its are compared with the decay reasons obtained by means of autoregression models of the local instrumentation of neutron flux. (Author)

  19. Zoanthids of the Cape Verde Islands and their symbionts: previously unexamined diversity in the Northeastern Atlantic

    OpenAIRE

    Reimer, J.D.; Hirose, M.; Wirtz, P.

    2010-01-01

    The marine invertebrate fauna of the Cape Verde Islands contains many endemic species due to their isolated location in the eastern Atlantic, yet research has not been conducted on most taxa here. One such group are the zoanthids or mat anemones, an order of benthic cnidarians (Hexacorallia: Zoantharia) common in many marine environments. In this study, the diversity of zoanthids in the Cape Verde Islands is specifically examined for the first time. Field images and sampling are combined with...

  20. Motivations of backpackers in the Cape Coast-Elmina Conurbation, Ghana

    OpenAIRE

    Frederick Dayour

    2013-01-01

    Research has shown that the backpacker market is one of the tourism markets that economically benefit local communities than the conventional market or mass tourists. The purpose of the study was to examine the motivations of backpackers in the Cape Coast-Elmina conurbation, Ghana. Questionnaire was used to collect data from 184 backpackers in Cape Coast and Elmina. Factor Analysis and some descriptive statistical analysis were employed in presenting the report. The st...

  1. Manifestations of inflammatory bowel disease in patients of Haitian and Cape Verdean descent.

    Science.gov (United States)

    Stallwood, Christopher; Shergill, Karenpreet; Wu, Joseph; Farraye, Francis A; Miller, Hannah L

    2015-07-01

    Several studies have reported unique ethnic phenotypes of inflammatory bowel disease (IBD). An appreciation of disease manifestations in different populations may improve clinical outcomes. There are no studies examining IBD in patients of Haitian or Cape Verdean descent. We sought to define the IBD phenotype in these populations. This was a retrospective review comparing Haitian and Cape Verdean immigrant IBD patients to Caucasians, all receiving care at Boston Medical Center in Boston, Massachusetts, USA. The following variables were analyzed: family history, smoking history, vaccinations/cancer screening, age of diagnosis, disease duration, disease location, medication use, and complications. Thirty-one Haitians and 21 Cape Verdeans were matched to Caucasian controls. Haitians (mean age 42 years) and Cape Verdeans (mean age 47 years) with Crohn's disease were diagnosed with IBD later than Caucasians (mean age 31 years, p = 0.04 and 0.02, respectively). Haitians with Crohn's were less likely to have a history of tobacco use compared to Caucasians (13% vs. 51%, p = 0.02). Cape Verdeans with Crohn's were less likely to have perianal involvement (0% vs. 50%, p = 0.01). Haitians with IBD were less likely to have ever used glucocorticoids (48% vs. 76%, p = 0.02). There was no difference in vaccination rates, cancer screening, or disease complications. This study demonstrates differences in IBD presentation and disease course among Haitians and Cape Verdeans. Our results suggest a more mild disease in these ethnic groups. Future studies are needed to identify the influence of environmental factors.

  2. Computational study of elements of stability of a four-helix bundle protein biosurfactant

    Science.gov (United States)

    Schaller, Andrea; Connors, Natalie K.; Dwyer, Mirjana Dimitrijev; Oelmeier, Stefan A.; Hubbuch, Jürgen; Middelberg, Anton P. J.

    2015-01-01

    Biosurfactants are surface-active molecules produced principally by microorganisms. They are a sustainable alternative to chemically-synthesized surfactants, having the advantages of being non-toxic, highly functional, eco-friendly and biodegradable. However they are currently only used in a few industrial products due to costs associated with production and purification, which exceed those for commodity chemical surfactants. DAMP4, a member of a four-helix bundle biosurfactant protein family, can be produced in soluble form and at high yield in Escherichia coli, and can be recovered using a facile thermal phase-separation approach. As such, it encompasses an interesting synergy of biomolecular and chemical engineering with prospects for low-cost production even for industrial sectors. DAMP4 is highly functional, and due to its extraordinary thermal stability it can be purified in a simple two-step process, in which the combination of high temperature and salt leads to denaturation of all contaminants, whereas DAMP4 stays stable in solution and can be recovered by filtration. This study aimed to characterize and understand the fundamental drivers of DAMP4 stability to guide further process and surfactant design studies. The complementary use of experiments and molecular dynamics simulation revealed a broad pH and temperature tolerance for DAMP4, with a melting point of 122.4 °C, suggesting the hydrophobic core as the major contributor to thermal stability. Simulation of systematically created in silico variants of DAMP4 showed an influence of number and location of hydrophilic mutations in the hydrophobic core on stability, demonstrating a tolerance of up to three mutations before a strong loss in stability occurred. The results suggest a consideration of a balance of stability, functionality and kinetics for new designs according to their application, aiming for maximal functionality but at adequate stability to allow for cost-efficient production using thermal

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

    Science.gov (United States)

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

    2009-01-01

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

  4. Clinical study on the primary stability of two dental implant systems with resonance frequency analysis.

    Science.gov (United States)

    Rabel, Annette; Köhler, Steffen Gerhard; Schmidt-Westhausen, Andrea Maria

    2007-09-01

    Primary stability has a major impact on the long-term success of dental implants. The aim of this study was to investigate the correlation of resonance frequency analysis (RFA) and insertion torque of self-tapping and non-self-tapping implants and their respective differences in primary stability. A group of 263 patients were treated with a total of 602 conically formed dental implants: 408 non-self-tapping Ankylos and 194 self-tapping Camlog. The maximum insertion torque during implant placement was recorded. Resonance frequency, measured as the implant stability quotient (ISQ), was assessed once immediately after insertion and twice 3 months later. Torque values of the non-self-tapping implants were significantly higher than those in the self-tapping group (p = 0.023). RFA did not show differences between the 2 groups (p = 0.956), but a correlation between ISQ values after implantation and 3 months after implant placement was measured (r = 0.712). Within the implant systems, no correlation between insertion torque and resonance frequency values could be determined (r = 0.305). Our study indicates that the ISQ values obtained from different implant systems are not comparable. The RFA does not appear suitable for the evaluation of implant stability when used as a single method. Higher insertion torque of the non-self-tapping implants appeared to confirm higher clinical primary stability.

  5. Wastewater Sludge Stabilization Using Lime A Case Study of West Ahwaz Wastewater Treatment Plant

    Directory of Open Access Journals (Sweden)

    Mehdi Farzadkia

    2009-01-01

    Full Text Available Lime stabilization is a chemical method used for wastewater sludge stabilization. It is capable of decreasing large quantities of pathogens and of preventing microbial degradation of sludge organic materials. The main objective of the present experimental research was to investigate stabilization of the sludge from west Ahwaz wastewater treatment plant by lime addition and to control if the microbial quality of this sludge conforms to the USEPA standards for sludge reuse and safe disposal. The study was carried out on a pilot scale in 5 stages over a period of 12 months (July 2005 to June 2006 at west Ahwaz wastewater treatment plant laboratory using raw sludge. For the purposes of this study, a 30-liter reactor was commissioned and loaded with sludge and appropriate quantities of hydrated lime were added based on the solid waste percent. The parameters used to determine stabilization efficiency were pH, Total Coliform, Fecal Coliform, and parasite eggs. The results showed that lime addition at a ratio of 265g Ca(OH2/kg. ds was the optimum level for sludge stabilization in westAhwazwastewater treatment plant, which is acceptable from both economic and technical viewpoints. The method is capable of achieving class B but never satisfied class A of USEPA standards.

  6. Dynamic Voltage Stability Studies using a Modified IEEE 30-Bus System

    Directory of Open Access Journals (Sweden)

    Oluwafemi Emmanuel Oni

    2016-09-01

    Full Text Available Power System stability is an essential study in the planning and operation of an efficient, economic, reliable and secure electric power system because it encompasses all the facet of power systems operations, from planning, to conceptual design stages of the project as well as during the systems operating life span. This paper presents different scenario of power system stability studies on a modified IEEE 30-bus system which is subjected to different faults conditions. A scenario whereby the longest high voltage alternating current (HVAC line is replaced with a high voltage direct current (HVDC line was implemented. The results obtained show that the HVDC line enhances system stability more compared to the contemporary HVAC line. Dynamic analysis using RMS simulation tool was used on DigSILENT PowerFactory.

  7. Healthcare provider views on the health effects of biomass fuel collection and use in rural Eastern Cape, South Africa: an ethnographic study

    NARCIS (Netherlands)

    Matinga, Margaret Njirambo; Annegarn, Harold J.; Clancy, Joy S.

    2013-01-01

    Policymakers at global level recognise that household biomass use in developing countries has significant health consequences. However, it is unclear how local-level health professionals perceive and respond to such health effects. This paper which is derived from the findings of a larger study on

  8. NONLINEAR MODEL OF STABILITY STUDY OF SYSTEM "SURFACE CONTROL – ACTUATOR" OF MANEUVERABLE UNMANNED AERIAL VEHICLE

    Directory of Open Access Journals (Sweden)

    V. N. Akimov

    2017-01-01

    Full Text Available One of the important problems of the designing of maneuverable unmanned aerial vehicles (UAV is to ensure aeroelastic stability with automatic control system (ACS. One of the possible types of aeroelastic instability of UAV with ACS is loss of stability in the system "surface control – actuator".  A nonlinear model for the study of the stability of the system "surface control – actuator" is designed for solving problems of joint design of airframe and ACS with the requirements of aeroelasticity. The electric actuator is currently the most widely used on highly maneuverable UAV. The wide bandwidth and the availability of frequency characteristic lifts are typical for the modern electric actuator. This exacerbates the problem of providing aeroelastic stability of the UAV with ACS, including the problem of ensuring the stability of the system "surface control – actuator". In proposed model the surface control, performing bending-torsion oscillations in aerodynamic flow, in fact, is the loading for the actuator. Experimental frequency characteristics of the isolated actuator, obtained for different levels of the control signal, are used for the mathematical description of the actuator, then, as dynamic hinge moment, which is determined by aeroelastic vibrations of the surface control in the air flow, is calculated. Investigation of the stability of the system "surface control – actuator" is carried out by frequency method using frequency characteristics of the open-loop system. The undeniable advantage of the proposed model is the simplicity of obtaining the transfer functions of the isolated actuator. The experiment by its definition is a standard method of determining frequency characteristics of the actuator in contrast to time-consuming experiments for determining the dynamic stiffness of the actuator (with the surface control or the transfer function of the actuator using electromechanical simulation of aeroelastic loading of the

  9. Temperature, salinity, microplankton abundance and other data from three cruises of the R/V Cape Hatteras in the NW Atlantic to study bacterial activity, August 2001 - March 2002 (NODC Accession 0001675)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data is from three cruises on the R/V Cape Hatteras taken in Aug and October 2001, and March 2002 from Boothbay Harbor Maine to the Sargasso Sea. The purpose of...

  10. THE EASTERN CAPE PROVINCE OF SOUTH AFRICA

    African Journals Online (AJOL)

    POT ENTIAL FOR CASSAVA PRODUCTION IN THE BATHURST RÉGION OF. THE EASTERN CAPE ... Cassava (Manihot escrtlenta) is a minor crop in South Africa that has had periodic rises in interest since it was first cultivated in the country. Interest .... Hardened tissue culture plants were used to establish this trial due to ...

  11. 76 FR 22719 - Cape Wind Energy Project

    Science.gov (United States)

    2011-04-22

    ... Energy Project AGENCY: Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE), Interior..., or disapprove a Construction and Operations Plan (COP) for the Cape Wind Energy Project located on..., easements, or rights-of-way for renewable energy projects on the OCS. The Secretary delegated that authority...

  12. Zoology Department, University of Cape Town

    African Journals Online (AJOL)

    NOTES ON THE ECOLOGY OF PATELLA CONCOLOR AND CELLANA. CAPENSlS, AND THE EFFECTS OF HUMAN CONSUMPTION ON. LIMPET POPULATIONS ... fixed sites to determine the amount of movement taking place. I am most grateful to Mrs. Giles of Cape Town for access to her collection of P. concolor,.

  13. Recovery of eastern Cape heathland after fire

    Directory of Open Access Journals (Sweden)

    A. M. F. G. Jacot Guillarmod

    1983-11-01

    Full Text Available In parts of the eastern Cape, fire is increasing in frequency and intensity in heathland, due mainly to the presence of adventive exotic tree species. These adventives also smother the indigenous vegetation under a dense canopy or with leaf litter. This heathland* flora requires a long period to reach its climax and under present conditions, this is rarely attained.

  14. The Cape Times's portrayal of school violence

    African Journals Online (AJOL)

    UVP

    2016-05-30

    May 30, 2016 ... the economy. It is concluded that even if the Cape Times paints an exaggerated and atypical picture of violence in the gang- ... bullying, shootings, stabbings, gangsterism, drug trafficking, theft of property and vandalism, racially motivated violence and ...... Pupils feeling heavy weight of gangs, violence and ...

  15. April 1992 Cape Mendocino, USA Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — On April 25, 1992 at 11:06 am local time (April 25 at 18:06 GMT), a magnitude 7.1 earthquake occurred in the Cape Mendocino area. Two additional earthquakes,...

  16. Zoology Department, University o/Cape Town

    African Journals Online (AJOL)

    Zoology Department, University o/Cape Town. ABSTRACT. Forty-six species were recorded in association with Patella spp., but most of these are casual associates, seeking temporary shelter. The shell surface offers an important substrate for algae. The amphipod Hyale grandicornla is often associated with Patella, ...

  17. Stability analysis of a recycling circuit of a BWR type reactor. Theoretical study

    International Nuclear Information System (INIS)

    Salinas H, J.G.; Espinosa P, G.; Gonzalez M, V.M.

    2000-01-01

    The Technology, Regulation and Services Management of the National Commission of Nuclear Safety and Safeguards financed and in coordinate form with the I.P.H. Department of the Metropolitan Autonomous-Iztapalapa University developed the present project with the purpose of studying the effect of the recycling system on the linear stability of a BWR reactor whose reference central is the Laguna Verde power station. The present project forms part of a work series focused to the linear stability of the nuclear reactor of the Unit 1 at Laguna Verde power station. The components of the recycling system considered for the study of stability are the recycling external circuit (recycling pumps, valves) and the internal circuit (downcomer, jet pumps, lower full, driers, separators). The mathematical model is obtained applying mass balances and movement quantity in each one of the mentioned circuits. With respect to the nucleus model two regions are considered, the first one is made of a flow in one phase and the second one of a flow in two phases. For modelling the biphasic region it is considered homogenous flow. Generally it is studied the system behavior in the frequency domain starting from the transfer function applied to four operational states which correspond to the lower stability zone in the map power-flow of the Unit 1 of Laguna Verde power station. The Nyquist diagrams corresponding to each state as well as their characteristic frequency were determined. The results show that exists a very clear dependence of the power-flow relation on the stability of the system. It was found that the boiling length is an important parameter for the linear stability of the system. The obtained results show that the characteristic frequencies in unstability zones are similar to the reported data of the Unit 1 of the Laguna Verde power station in the event of power oscillations carried out in January 1995. (Author)

  18. Linear stability of a fuel channel uniformly heated considering retrofeeding by vacuum. Theoretical study

    International Nuclear Information System (INIS)

    Gonzalez M, V.; Salinas H, J.G.; Espinosa P, G.

    2000-01-01

    The Technology, Regulation and Services Management of the National Commission of Nuclear Safety and Safeguards in coordinated form with the IPH Department of the Metropolitan Autonomous-Iztapalapa University, developed the present project to study the linear stability in a fuel channel uniformly heated with effects of retrofeeding by vacuums. In this study the methodology used in the analysis of linear stability of the nuclear reactor unit 1 at Laguna Verde power plant is described which represented by an average channel uniformly heated. The conceptual model consists of two cells which represent the two regions in which is divided the channel according to the cooling is in one and two phases, considering the boiling length dependent in the time. It is used the homogeneous flux models for describing the thermohydraulic behavior of the cooling in the two phases region. The neutron processes with the punctual model of the neutron kinetics with a group of retarded neutrons precursors are described. It is studied the behavior of the system in the frequency domain with the transfer functions obtained and it is characterized in four operation states corresponding to the four corners of the low stability zone in the map power-flow Laguna Verde power plant. For these operation states the characteristic frequency is determined and the corresponding Nyquist diagrams are obtained. The results show that the system stability depends on the power-flow relation and that the operations which implicate a reduction of this relation improve the stability of the system (reducing the power introducing control bars with constant cooling flow or increase cooling flow with bars pattern established). The obtained results with effects of retrofeeding by vacuums show that the value of the characteristic frequency is modified very little with respect to the model without retrofeeding, therefore the thermohydraulic processes seem to determine the response of the stability of the system

  19. Experimental study of silty clay stabilization with cement and lime in multan, pakistan

    International Nuclear Information System (INIS)

    Sultan, T.

    2014-01-01

    Stabilization is valuable substitute for advancing the soil characteristics. The engineering features gained after stabilization differs broadly owing to non-uniformity in constitutions of soil. This study describes an assessment of cement and lime additives for advancing soils ventures. The effectiveness of lime and cement stabilization on geotechnical characteristics of the in situ soil has also been described in the paper. The additives like cement and lime were added in different dosage rates to examine the change in properties of the in situ soil. Cement addition caused an increase in unconfined compression strength (UCS) throughout from 4% to 16% of cement. Moreover, it has been observed that by adding lime, the early strength of clay increases up to 6% of lime but for long term strength i.e. 28 days maximum strengths is achieved for 4% of lime. It also confirms that with more percentage of lime and longer duration of curing, it expands. In addition to the strength behavior of samples at various percentages of cement and lime, the deflection at failure point was also examined. In order to make a straight comparison, both cement and lime stabilized soils were also tested in laboratory. Generally, the performance of Portland cement-stabilized soils was advanced to lime in the experiments performed. (author)

  20. Tuberculin skin test conversion and primary progressive tuberculosis disease in the first 5 years of life: a birth cohort study from Cape Town, South Africa.

    Science.gov (United States)

    Martinez, Leonardo; le Roux, David M; Barnett, Whitney; Stadler, Attie; Nicol, Mark P; Zar, Heather J

    2018-01-01

    Tuberculosis is a leading cause of global childhood mortality. However, the epidemiology and burden of tuberculosis in infancy is not well understood. We aimed to investigate tuberculin skin test conversion and tuberculosis in the Drakenstein Child Health study, a South African birth cohort in a community in which tuberculosis incidence is hyperendemic. In this prospective birth cohort study, we enrolled pregnant women older than 18 years who were between 20 and 28 weeks' gestation and who were attending antenatal care in a peri-urban, impoverished South African setting. We followed up their children for tuberculosis from birth until April 1, 2017, or age 5 years. All children received BCG vaccination at birth. Tuberculin skin tests were administered to children at 6, 12, 24, 36, 48, and 60 months of age, and at the time of a lower respiratory tract infection. An induration reaction of 10 mm or more was considered to be a tuberculin skin test conversion. To prevent boosting, we censored children with a reactive, negative tuberculin skin test. Among 915 mother-child pairs (201 [22%] HIV-positive mothers and two [tuberculosis, and 0·7 (0·4-1·0) for microbiologically confirmed tuberculosis. Isoniazid preventive therapy was effective in averting disease progression (adjusted hazard ratio 0·22, 95% CI 0·08-0·63; ptuberculosis than were those without one (2·27, 1·42-3·62; ptuberculosis infection and disease. Multifaceted interventions, such as isoniazid preventive therapy and tuberculosis screening of infants with LRTIs, beginning early in life, are needed in high-burden settings. Bill & Melinda Gates Foundation, Medical Research Council South Africa, and National Research Foundation South Africa.

  1. A study of product stability of commercial probiotic fermented milk and yoghurt

    OpenAIRE

    Liu, Xiaojiao

    2011-01-01

    In this study, the stability of three probiotic fermented milk products (‘Cultura Naturell’, ‘Biola Syrnet Lettmelk Naturell’ and ‘Biola Pluss Yoghurt Mild Naturell’) produced by TINE BA was studied and samples from each production were studied at three different times within designated shelf-life. The study focused mainly on the viability of probiotic bacteria during storage, which is a key criterion for quality evaluation of probiotic dairy products. Other parameters (pH, viscosity, organic...

  2. A new experimental approach to study the stability of logistic map

    International Nuclear Information System (INIS)

    Rani, Mamta; Agarwal, Rashi

    2009-01-01

    Remarkably benign looking logistic transformations x n+1 = rx n (1 - x n ) for choosing x 0 between 0 and 1 and 0 < r ≤ 4 have found a celebrated place in chaos, fractals and discrete dynamics. The purpose of this paper is to enhance the capabilities of logistic map via superior iterations. Stability of logistic map has been studied by running computer programs. Logistic map is stable for 0 < r ≤ 3.2 in Picard orbit. In superior orbit, we see that the range of stability of logistic map increases drastically. Also, chaotic behavior of logistic map disappears in certain cases.

  3. Stability Estimates for a Twisted Rod Under Terminal Loads: A Three-dimensional Study

    KAUST Repository

    Majumdar, Apala

    2012-03-01

    The stability of an inextensible unshearable elastic rod with quadratic strain energy density subject to end loads is considered. We study the second variation of the corresponding rod-energy, making a distinction between in-plane and out-of-plane perturbations and isotropic and anisotropic cross-sections, respectively. In all cases, we demonstrate that the naturally straight state is a local energy minimizer in parameter regimes specified by material constants. These stability results are also accompanied by instability results in parameter regimes defined in terms of material constants. © 2012 Springer Science+Business Media B.V.

  4. Nonlinear stability and control study of highly maneuverable high performance aircraft, phase 2

    Science.gov (United States)

    Mohler, R. R.

    1992-01-01

    This research should lead to the development of new nonlinear methodologies for the adaptive control and stability analysis of high angle-of-attack aircraft such as the F18 (HARV). The emphasis has been on nonlinear adaptive control, but associated model development, system identification, stability analysis and simulation is performed in some detail as well. Various models under investigation for different purposes are summarized in tabular form. Models and simulation for the longitudinal dynamics have been developed for all types except the nonlinear ordinary differential equation model. Briefly, studies completed indicate that nonlinear adaptive control can outperform linear adaptive control for rapid maneuvers with large changes in alpha. The transient responses are compared where the desired alpha varies from 5 degrees to 60 degrees to 30 degrees and back to 5 degrees in all about 16 sec. Here, the horizontal stabilator is the only control used with an assumed first-order linear actuator with a 1/30 sec time constant.

  5. The study of stability, combustion characteristics and performance of water in diesel emulsion fuel

    Directory of Open Access Journals (Sweden)

    Syafiq Zulkifli

    2017-01-01

    Full Text Available A single cylinder diesel engine study of water in diesel emulsions was conducted to investigate the stability effect of emulsion fuel on three different fuel blends and the water emulsification effect on the engine performance. Emulsified fuels contained 2% of surfactant including Span 80 Tween 80 and tested 10 HLB number. The blends also varied of 5%, 10% and 15% of water in diesel ratios namely as BSW5, BSW10 and BSW15. The fuel blends performance was tested using a single cylinder, direct injection diesel engine, operating at 1860 rpm. The results on stability reveal that high shear homogenizer yields more stability on emulsion fuel than mechanical stirrer and ultrasonic water bath. The engine performance results show that the ignition delay and peak pressure increase with the increment of water percentage up to 15%. However, the results indicate the increment of water percentage is also shows a significant decrease in engine power.

  6. Western Wind and Solar Integration Study Phase 3 – Frequency Response and Transient Stability

    Energy Technology Data Exchange (ETDEWEB)

    Miller, N. W. [GE Energy Management, Schenectady, NY (United States); Shao, M. [GE Energy Management, Schenectady, NY (United States); Pajic, S. [GE Energy Management, Schenectady, NY (United States); D' Aquila, R. [GE Energy Management, Schenectady, NY (United States)

    2014-12-01

    Power system operators and utilities worldwide have concerns about the impact of high-penetration wind and solar generation on electric grid reliability (EirGrid 2011b, Hydro-Quebec 2006, ERCOT 2010). The stability of North American grids under these conditions is a particular concern and possible impediment to reaching future renewable energy goals. Phase 3 of the Western Wind and Solar Integration Study (WWSIS-3) considers a 33% wind and solar annual energy penetration level that results in substantial changes to the characteristics of the bulk power system, including different power flow patterns, different commitment and dispatch of existing synchronous generation, and different dynamic behavior of wind and solar generation. WWSIS-3 evaluates two specific aspects of fundamental frequency system stability: frequency response and transient stability.

  7. Study on Roll Instability Mechanism and Stability Index of Articulated Steering Vehicles

    Directory of Open Access Journals (Sweden)

    Xuefei Li

    2016-01-01

    Full Text Available This study examines the roll instability mechanism and stability index of articulated steering vehicles (ASVs by taking wheel loaders as the research object. A seven-degree-of-freedom nonlinear dynamics model of the ASVs is built on the basis of multibody dynamics. A physical prototype model of an ASV is designed and manufactured to validate the dynamic model. Test results reasonably agree with the simulation results, which indicates that the established dynamic model can reasonably describe ASV movements. Detailed analysis of the rollover stability of the wheel loader is performed with the use of the established dynamic model. Analysis results show that rollover will occur when the roll angular velocity exceeds a critical threshold, which is affected by lateral acceleration and slope angle. On this basis, a dynamic stability index applicable to the ASVs is presented.

  8. Formulation studies on stability of solid-state proteases for detergent applications

    DEFF Research Database (Denmark)

    Ay, Suzan Biran; Jensen, Anker Degn; Kiil, Søren

    2012-01-01

    Enzymes are one of the most important components in the laundry detergents. They effectively contribute to the washing process by decreasing energy and water consumption, reducing environmental load of detergent products, leaving non-toxic water effluents and providing fabric care. Ensuring proper...... storage stability of enzyme granulates in the chemically hostile detergent matrix is a major challenge. It is believed that the main factors responsible for activity loss are humidity and H2O2 released from the bleaching agents. In this study, the mechanism and inactivation kinetics of freeze......-dried detergent protease, Savinase, were determined in a newly developed experimental setup, providing rapid assessment of solid-state enzyme stability under oxidizing conditions. The method was based on exposure of an enzyme column to known concentrations of H2O2 (g) and humidity in a thermally stabilized...

  9. Differences in CAPE between wet and dry spells of the monsoon over the southeastern peninsular India

    Science.gov (United States)

    Mohan, T. S.; Rao, T. N.; Rajeevan, M.

    2018-03-01

    In the present research we explored the variability of convective available potential energy (CAPE) during wet and dry spells over southeast India. Comparison between India Meteorological Department (IMD) observations and reanalysis products (NCEP, ERA-interim, and MERRA) reconfirms that gridded data sets can be utilized to fill the void of observations. Later, GPS radiosonde measurements made at Gadanki (13.5 N, 79.2 E) Andre analysis output are utilized to address key scientific issues related to CAPE over the southeastern peninsular region. They are: (1) How does CAPE vary between different spells of the Indian summer monsoon (i.e., from wet to dry spell)? (2) Does differences in CAPE and in the vertical structure of buoyancy between spells are localized features over Gadanki or observed all over southeastern peninsular region? (3) What physical/dynamical processes are responsible for the differences in CAPE between spells and how do they affect the convection growth in dry spell? Interestingly, CAPE is higher in wet spell than in dry spell, in contrast to the observations made elsewhere over land and warm oceans. Similar feature (high CAPE in wet spell) is observed at all grid points in the southeastern peninsular India. Furthermore, vertical buoyancy profiles show only one peak in the middle-upper troposphere in wet spell, while two peaks are observed in most of the profiles (66%) in dry spell over the entire study region in all the reanalysis products. Plausible mechanisms are discussed for the observed CAPE differences. They are, among others, timing of sounding with reference to rain occurrence, rapid buildup of surface instabilities, moistening of lower troposphere by evaporation of the surface moisture in wet spell, enhanced low-level moisture convergence, evaporation of rain in relatively warm and dry atmosphere, and reduction of positive buoyancy in dry spell. The omnipresence of stable layers and strong and deep shear in the presence of weak updrafts

  10. The barriers that women face when choosing food for their primary school children: A case study in the Western Cape Province, South Africa

    Directory of Open Access Journals (Sweden)

    Y Smit

    2017-10-01

    Full Text Available Background. Unhealthy food choices made by mothers can impact negatively on child health and may lead to unhealthy eating behaviours that persist into adulthood. Choosing food is a complex process influenced by many factors. Objectives. To determine the factors that influence mothers’ food choices and to investigate barriers to purchasing healthy food. Methods. A cross-sectional, descriptive study, with an analytical component, was conducted. Mothers (N=476 were recruited from three randomly selected primary schools, from a low, middle and high quintile. A self-administered questionnaire was used to collect data on demographics, knowledge, attitude and practices of mothers. Six focus groups (FG (two per school were conducted to investigate the factors that prevent mothers from making healthy dietary decisions. Results. The mean nutrition knowledge score for the group was 68.6%. Nutrition knowledge was significantly lower (p<0.01 in mothers from the lower quintile school (64.0%. Primary factors influencing food purchases were cost (60%, nutritional value (37% and time constraints (29%. Primary sources of nutrition information included magazines and health professionals at 62% and 44%, respectively. Time constraints resulted in mothers purchasing convenience foods more often (p=0.001. The main barriers identified were mixed media messages, the school environments and supermarket layouts. Conclusion. Nutrition education campaigns should include practical advice, e.g. the preparation of economical, wholesome meals. Policymakers should monitor increasing prices of healthy foods. School and supermarket environments, as well as the food industry, can play a pivotal role in facilitating mothers to make healthy food choices

  11. Seasonal variation in the acute effect of particulate air pollution on mortality in the China Air Pollution and Health Effects Study (CAPES)

    Science.gov (United States)

    Chen, Renjie; Peng, Roger D.; Meng, Xia; Zhou, Zhijun; Chen, Bingheng; Kan, Haidong

    2013-01-01

    Epidemiological findings concerning the seasonal variation in the acute effect of particulate matter (PM) are inconsistent. We investigated the seasonality in the association between PM with an aerodynamic diameter of less than 10 μm (PM10) and daily mortality in 17 Chinese cities. We fitted the “main” time-series model after adjustment for time-varying confounders using smooth functions with natural splines. We established a “seasonal” model to obtain the season-specific effect estimates of PM10, and a “harmonic” model to show the seasonal pattern that allows PM10 effects to vary smoothly with the day in a year. At the national level, a 10 μg/m3 increase in the two-day moving average concentrations (lag 01) of PM10 was associated with 0.45% [95% posterior interval (PI), 0.15% to 0.76%], 0.17% (95% PI, −0.09% to 0.43%), 0.55% (95% PI, 0.15% to 0.96%) and 0.25% (95%PI, −0.05% to 0.56%) increases in total mortality for winter, spring, summer and fall, respectively. For the smoothly-varying plots of seasonality, we identified a two-peak pattern in winter and summer. The observed seasonal pattern was generally insensitive to model specifications. Our analyses suggest that the acute effect of particulate air pollution could vary by seasons with the largest effect in winter and summer in China. To our knowledge, this is the first multicity study in developing countries to analyze the seasonal variations of PM-related health effects. PMID:23500824

  12. Monitoring organic and inorganic pollutants in juvenile live sea turtles: results from a study of Chelonia mydas and Eretmochelys imbricata in Cape Verde.

    Science.gov (United States)

    Camacho, María; Boada, Luis D; Orós, Jorge; López, Pedro; Zumbado, Manuel; Almeida-González, Maira; Luzardo, Octavio P

    2014-05-15

    Despite the current environmental concern regarding the risk posed by contamination in marine ecosystems, the concentrations of pollutants in sea turtles have not been thoroughly elucidated. In the current study, we determined the concentrations of 18 organochlorine pesticides (OCPs), 18 polychlorinated biphenyls (PCBs), 16 polycyclic aromatic hydrocarbons (PAHs) and 11 inorganic elements (Cu, Mn, Pb, Zn, Cd, Ni, Cr, As, Al, Hg and Se) for the first time in two sea turtle species (Chelonia mydas and Eretmochelys imbricata). Only five of the 18 analyzed OCPs were detected in both species. The average total OCP concentration was higher in green turtles than in hawksbills (0.33 ng/ml versus 0.20 ng/ml). Higher concentrations of individual congeners and total PCBs were also detected in green turtles than in hawksbills (∑PCBs=0.73ng/ml versus 0.19 ng/ml), and different PCB contamination profiles were observed in these two species. Concerning PAHs, we also observed a different contamination profile and higher levels of contamination in green turtles (∑PAHs=12.06 ng/ml versus 2.95 ng/ml). Di- and tri-cyclic PAHs were predominant in both populations, suggesting a petrogenic origin, rather than urban sources of PAHs. Additionally, all of the samples exhibited detectable levels of the 11 inorganic elements. In this case, we also observed relevant differences between both species. Thus, Zn was the most abundant inorganic element in hawksbills (an essential inorganic element), whereas Ni, a well-known toxicant, was the most abundant inorganic element in green turtles. The presence of contaminants is greater in green turtles relative to hawksbill turtles, suggesting a greater exposure to hazardous chemical contaminants for green turtles. These results provide baseline data for these species that can serve for future monitoring purposes outlined in the EU's Marine Strategy Framework Directive. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. A Study on Stability of Limit Cycle Walking Model with Feet: Parameter Study

    Directory of Open Access Journals (Sweden)

    Yonggwon Jeon

    2013-01-01

    Full Text Available In this paper, two kinds of feet, namely, curved and flat feet, are added to limit cycle walking model to investigate its stability properties. Although both models are already proposed and are investigated, most previous works are focused on efficiency and gait behaviors. Only the stability properties of the simplest walking model conceived Garcia et al. are well defined. Therefore, there is still a need for a precise research on the effect of feet, especially in the view of local stability, bifurcation route to chaos, global stability, falling boundary and energy balance line. Therefore, this article revisits the stability analysis of limit cycle walking model with various foot shape. To analyze the effects of feet, we re-derive the equation of motion of modified models by adding one more parameter of foot shape than the simplest walking model. Also, the falling boundary and energy balance line of modified models are derived to get proper initial conditions for stable walking and to explain global stability. Simulation results show us that the curved feet can enlarge both stable walking range and area of basin of attraction while the case of flat feet depends on foot shape parameter.

  14. Longitudinal Stability Study for the FACET-II e+ Damping Ring

    Energy Technology Data Exchange (ETDEWEB)

    Bane, Karl [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2016-11-29

    This is an initial study of the longitudinal, single-bunch stability in the proposed FACET-II e+ damping ring. It is preliminary because, at present, only a few specific features of the vacuum chamber are known.

  15. LONG TERM STABILITY STUDY AT FNAL AND SLAC USING BINP DEVELOPED HYDROSTATIC LEVEL SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Seryi, Andrei

    2003-05-28

    Long term ground stability is essential for achieving the performance goals of the Next Linear Collider. To characterize ground motion on relevant time scales, measurements have been performed at three geologically different locations using a hydrostatic level system developed specifically for these studies. Comparative results from the different sites are presented in this paper.

  16. Aggregated Modelling for Wind Farms for Power System Transient Stability Studies

    DEFF Research Database (Denmark)

    Liu, Hongzhi; Chen, Zhe

    2012-01-01

    to detailed modelling that models every wind turbines individually and the interconnections among them. In this paper, three aggregated modelling techniques, namely, multi-machine equivalent aggregation, full aggregation and semi-aggregation are presented for power system transient stability studies based...

  17. A comparative study of vertical stabilities in the Arabian sea and Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sastry, J.S.; Rao, D.P.

    Stabilities in the upper 300 m in the Arabian Sea and the Bay of Bengal are computed and presented seasonwise. The water column in the Bay of Bengal is more strongly stratified than that in the Arabian Sea. These studies suggest that the vertical...

  18. The defect structure of yttria-stabilized zirconia, studied by quasielastic diffuse neutron scattering

    DEFF Research Database (Denmark)

    Andersen, Niels Hessel; Clausen, Kurt Nørgaard; Hackett, M. A.

    1986-01-01

    The static defect structure of the oxygen ion conductor Y2O3 stabilized zirconia has been studied at room temperature by coherent diffuse neutron scattering from single crystal samples containing nominally 9.4, 12, 15 and 18 mol% Y2O3. There are two principal contributions to the observed diffuse...

  19. An inter-laboratory stability study of roll-to-roll coated flexible polymer solar modules

    DEFF Research Database (Denmark)

    Gevorgyan, Suren; Medford, Andrew James; Bundgaard, Eva

    2011-01-01

    O (nanoparticulate, thin film) were employed as electron transport layers. The devices were all tested at Risø DTU and the functional devices were subjected to an inter-laboratory study involving the performance and the stability of modules over time in the dark, under light soaking and outdoor conditions. 24...

  20. Numerical experiments in the stability of leading edge boundary layer flow. A two-dimensional study

    NARCIS (Netherlands)

    Theofilis, Vassilios; Theofilis, V.

    1993-01-01

    A numerical study is performed in order to gain insight to the stability of the infinite swept attachment line boundary layer. The basic flow is taken to be of the Hiemenz class with an added cross-flow giving rise to a constant thickness boundary layer along the attachment line. The full

  1. Diagnostic stability among chronic patients with functional psychoses: an epidemiological and clinical study

    Directory of Open Access Journals (Sweden)

    Jakobsen Klaus D

    2007-08-01

    Full Text Available Abstract Background Diagnostic stability and illness course of chronic non-organic psychoses are complex phenomena and only few risk factors or predictors are known that can be used reliably. This study investigates the diagnostic stability during the entire course of illness in patients with non-organic psychoses and attempts to identify non-psychopathological risk factors or predictors. Method 100 patients with functional psychosis were initially characterised using the Operational Criteria Checklist for Psychotic Illness and Affective Illness (OPCRIT, medical records and health registers. To study the stability of diagnoses (i.e. shifts per time, we used registry data to define four measures of diagnostic variation that were subsequently examined in relation to four possible measures of time (i.e. observation periods or hospitalisation events. Afterwards, we identified putative co-variables and predictors of the best measures of diagnostic stability. Results All four measures of diagnostic variation are very strongly associated with numbers-of-hospitalisations and less so with duration-of-illness, duration-of-hospitalisation and with year-of-first-admission. The four measures of diagnostic variation corrected for numbers-of-hospitalisations were therefore used to study the diagnostic stability. Conventional predictors of illness course – e.g. age-of-onset and premorbid-functioning – are not significantly associated with stability. Only somatic-comorbidity is significantly associated with two measures of stability, while family-history-of-psychiatric-illness and global-assessment-of-functioning (GAF scale score show a trend. However, the traditional variables age-of-first-admission, civil-status, first-diagnosis-being-schizophrenia and somatic-comorbidity are able to explain two-fifth of the variation in numbers-of-hospitalisations. Conclusion Diagnostic stability is closely linked with the contact between patient and the healthcare system

  2. Geostationary Coastal and Air Pollution Events (GEO-CAPE) Sensitivity Analysis Experiment

    Science.gov (United States)

    Lee, Meemong; Bowman, Kevin

    2014-01-01

    Geostationary Coastal and Air pollution Events (GEO-CAPE) is a NASA decadal survey mission to be designed to provide surface reflectance at high spectral, spatial, and temporal resolutions from a geostationary orbit necessary for studying regional-scale air quality issues and their impact on global atmospheric composition processes. GEO-CAPE's Atmospheric Science Questions explore the influence of both gases and particles on air quality, atmospheric composition, and climate. The objective of the GEO-CAPE Observing System Simulation Experiment (OSSE) is to analyze the sensitivity of ozone to the global and regional NOx emissions and improve the science impact of GEO-CAPE with respect to the global air quality. The GEO-CAPE OSSE team at Jet propulsion Laboratory has developed a comprehensive OSSE framework that can perform adjoint-sensitivity analysis for a wide range of observation scenarios and measurement qualities. This report discusses the OSSE framework and presents the sensitivity analysis results obtained from the GEO-CAPE OSSE framework for seven observation scenarios and three instrument systems.

  3. A 'private adventure'? John Herschel's Cape voyage and the production of the 'Cape Results'

    Science.gov (United States)

    Ruskin, Steven William

    2002-07-01

    This dissertation considers the life of John Herschel (1792 1871) from the years 1833 to 1847. In 1833 Herschel sailed from London to Cape Town, southern Africa, to undertake (at his own expense) an astronomical exploration of the southern heavens, as well as a terrestrial exploration of the area around Cape Town. After his return to England in 1838, he was highly esteemed and became Britain's most recognized scientist. In 1847 his southern hemisphere astronomical observations were published as the Cape Results. The main argument of this dissertation is that Herschel's voyage, and the publication of the Cape Results, in addition to their contemporary scientific importance, were also significant for nineteenth-century politics and culture. This dissertation is a two-part dissertation. The first part is entitled “John Herschel's Cape Voyage: Private Science, Public Imagination, and the Ambitions of Empire”; and the second part, “The Production of the Cape Results.” In the first part it is demonstrated that the reason for Herschel's cultural renown was the popular notion that his voyage to the Cape was a project aligned with the imperial ambitions of the British government. By leaving England for one of its colonies, and pursuing there a significant scientific project, Herschel was seen in the same light as other British men of science who had also undertaken voyages of exploration and discovery. It is then demonstrated, in the second part of this work, that the production of the Cape Results, in part because of Herschel's status as Britain's scientific figurehead, was a significant political and cultural event. In addition to the narrow area of Herschel scholarship, this dissertation touches on other areas of research in the history of science as well: science and culture, science and empire, science and politics, and what has been called the “new” history of scientific books.

  4. Development of probiotic tablets using microparticles: viability studies and stability studies.

    Science.gov (United States)

    e Silva, J P Sousa; Sousa, Sérgio C; Costa, Paulo; Cerdeira, Emília; Amaral, Maria H; Lobo, José Sousa; Gomes, Ana M; Pintado, Maria M; Rodrigues, Dina; Rocha-Santos, Teresa; Freitas, Ana C

    2013-03-01

    Alternative vectors to deliver viable cells of probiotics, to those conferring limited resistance to gastrointestinal conditions, still need to be sought. Therefore the main goal of the study was to develop tablets able to protect entrapped probiotic bacteria from gastric acidity, thus providing an easily manufacturing scale-up dosage form to deliver probiotics to the vicinity of the human colon. Whey protein concentrate microparticles with Lactobacillus paracasei L26 were produced by spray-drying and incorporated in tablets with cellulose acetate phthalate and sodium croscarmellose. The viability of L. paracasei L.26 throughout tableting as well as its gastric resistance and release from the tablets were evaluated. Storage stability of L. paracasei L26 tablets was also performed by evaluation of viable cells throughout 60 days at 23°C and 33% relative humidity. A decrease of approximately one logarithmic cycle was observed after the acid stage and the release of L. paracasei L26 from the tablets occurred only after 4 h in the conditions tested. Microencapsulated L. paracasei L26 in tablets revealed some susceptibility to the storage conditions tested since the number of viable cells decreased 2 log cycles after 60 days of storage. However, the viability of L. paracasei L26 after 45 days of storage did not reveal significant susceptibility upon exposure to simulated gastrointestinal conditions. The developed probiotic tablets revealed to be potential vectors for delivering viable cells of L. paracasei L26 and probably other probiotics to persons/patients who might benefit from probiotic therapy.

  5. Validation of analytical methods for the stability studies of naproxen suppositories for infant and adult use

    International Nuclear Information System (INIS)

    Rodriguez Hernandez, Yaslenis; Suarez Perez, Yania; Garcia Pulpeiro, Oscar

    2011-01-01

    Analytical and validating studies were performed in this paper, with a view to using them in the stability studies of the future formulations of naproxen suppositories for children and adults. The most influential factors in the naproxen stability were determined, that is, the major degradation occurred in acid medium, oxidative medium and by light action. One high-performance liquid chromatography-based method was evaluated, which proved to be adequate to quantify naproxen in suppositories and was selective against degradation products. The quantification limit was 3,480 μg, so it was valid for these studies. Additionally, the parameters specificity for stability, detection and quantification limits were evaluated for the direct semi-aqueous acid-base method, which was formerly validated for the quality control and showed satisfactory results. Nevertheless, the volumetric methods were not regarded as stability indicators; therefore, this method will be used along with the chromatographic methods of choice, that is, thin-layer chromatography and highperformance liquid chromatography, to determine the degradation products

  6. A retrospective study evaluating the efficacy of identification and management of sepsis at a district-level hospital internal medicine department in the Western Cape Province, South Africa, in comparison with the guidelines stipulated in the 2012 Survivi

    Directory of Open Access Journals (Sweden)

    Raisa Bhikoo

    2017-08-01

    Full Text Available Background. Currently there is little information on the identification, management and outcomes of patients with sepsis in developing countries. Simple cost-effective measures such as accurate identification of patients with sepsis and early antibiotic administration are achievable targets, within reach without having to make use of unsustainable protocols constructed in developed countries. Objectives. To assess the ability of clinicians at a district-level hospital to identify and manage sepsis, and to assess patient outcome in terms of in-hospital mortality and length of hospital stay given the above management. Methods. A retrospective descriptive study design was used, analysing data from the routine burden of disease audit done on a 3-monthly basis at Karl Bremer Hospital (KBH in the Western Cape Province, South Africa. Results. The total sample size obtained was 70 patients, of whom 18 (25.7% had an initial triage blood pressure indicative of sepsis-induced hypotension. However, only 1 (5.5% of these 18 patients received an initial crystalloid fluid bolus of at least 30 mL/kg. The median time that elapsed before administration of antibiotics in septic shock was 4.25 hours. Furthermore, a positive delay in antibiotic administration (p=0.0039 was demonstrated. The data also showed that 8/12 patients (66.7% with septic shock received inappropriate amounts of fluids. The in-hospital mortality rate for sepsis was 4/24 (16.7%, for severe sepsis 11/34 (32.3% and for septic shock a staggering 9/12 (75.0%. Conclusions. The initial classification process and management of sepsis by clinicians at KBH is flawed. This inevitably leads to an increase in in-hospital mortality.

  7. Screening and Brief Interventions for Alcohol and Other Drug Use Among Pregnant Women Attending Midwife Obstetric Units in Cape Town, South Africa: A Qualitative Study of the Views of Health Care Professionals.

    Science.gov (United States)

    Petersen Williams, Petal; Petersen, Zaino; Sorsdahl, Katherine; Mathews, Catherine; Everett-Murphy, Katherine; Parry, Charles D H

    2015-01-01

    Despite the negative consequences of alcohol and other drug use during pregnancy, few interventions for pregnant women are implemented, and little is known about their feasibility and acceptability in primary health care settings in South Africa. As part of the formative phase of screening, brief intervention, and referral to treatment for substance use among women presenting for antenatal care, the present study explored health care workers' attitudes and perceptions about screening, brief intervention, and referral to treatment among this population. Forty-three health care providers at 2 public sector midwife obstetric units in Cape Town, South Africa, were interviewed using an open-ended, semistructured interview schedule designed to identify factors that hinder or support the implementation of screening, brief intervention, and referral to treatment for substance use in these settings. Transcribed interviews were analyzed using the framework approach. Health care providers agreed that there is a substantial need for screening, brief intervention, and referral to treatment for substance use among pregnant women and believe such services potentially could be integrated into routine care. Several women-, staff-, and clinic-level barriers were identified that could hinder the successful implementation in antenatal services. These barriers included the nondisclosure of alcohol and other drug use, the intervention being considered as an add-on service or additional work, negative staff attitudes toward implementation of an intervention, poor staff communication styles such as berating women for their behavior, lack of interest from staff, time constraints, staff shortages, overburdened workloads, and language barriers. The utility of screening, brief intervention, and referral to treatment for addressing substance use among pregnant women in public health midwife obstetric units was supported, but consideration will need to be given to addressing a variety of

  8. Comparison of nectar foraging efficiency in the Cape honeybee ...

    African Journals Online (AJOL)

    1987-03-17

    Mar 17, 1987 ... Comparison of nectar foraging efficiency in the Cape honeybee, Apis mellifera capensis Escholtz, and the African honeybee, Apis mellifera adansonii Latreille,. , in the western Cape Province. P.V. W-Worswick*. Department of Zoology, University of Cape Town, Rondebosch 7700 Republic of South Africa.

  9. Validating homicide rates in the Western Cape Province, South Africa

    African Journals Online (AJOL)

    Background. The Western Cape Province had the highest homicide rates in South Africa during the early 2000s. South African Police Service (SAPS) data suggested a significant decline in homicide rates in the Western Cape since 2007. It ranked second highest to the Eastern Cape Province until 2013 and ranked highest ...

  10. The ABSA Cape Epic Mountain Bike Challenge: impacts and legacies

    African Journals Online (AJOL)

    The Absa Cape Epic mountain bike race is held in and around the mountainous areas outside Cape Town, in the Western Cape Province of South Africa, since 2004. The 700km-plus race, along farm roads and mountain tracks, extends over an eight day period. The race is limited to 600 two-person male and female teams, ...

  11. Territoriality of Cape Sugarbirds ( Promerops cafer ) between and ...

    African Journals Online (AJOL)

    Territoriality of Cape Sugarbirds (Promerops cafer) between and within breeding seasons. KM Calf, CT Downs, MI Cherry. Abstract. Cape Sugarbirds are southern African endemics, found in fynbos vegetation of the Western and Eastern Cape Provinces of South Africa, and they feed almost exclusively on the nectar of ...

  12. 33 CFR 117.823 - Cape Fear River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Cape Fear River. 117.823 Section... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements North Carolina § 117.823 Cape Fear River. The draw of the Cape Fear Memorial Bridge, mile 26.8, at Wilmington need not open for the passage of vessel from 8...

  13. Influence of atmospheric stability on wind-turbine wakes: A large-eddy simulation study

    Science.gov (United States)

    Abkar, Mahdi; Porté-Agel, Fernando

    2014-05-01

    In this study, large-eddy simulation is combined with a turbine model to investigate the influence of atmospheric stability on wind-turbine wakes. In the simulations, subgrid-scale turbulent fluxes are parameterized using tuning-free Lagrangian scale-dependent dynamic models. These models optimize the local value of the model coefficients based on the dynamics of the resolved scales. The turbine-induced forces are parameterized with an actuator-disk model with rotation. In this technique, blade-element theory is used to calculate the lift and drag forces acting on the blades. Emphasis is placed on the structure and characteristics of wind-turbine wakes in the cases where the incident flows to the turbine have the same mean velocity at the hub height but different stability conditions. The simulation results show that atmospheric stability has a significant effect on the spatial distribution of the mean velocity deficit and turbulent fluxes in the wake region. In particular, the magnitude of the velocity deficit increases with increasing stability in the atmosphere. In addition, the locations of the maximum turbulence intensity and turbulent stresses are closer to the turbine in convective boundary layer compared with neutral and stable ones. Detailed analysis of the resolved turbulent kinetic energy (TKE) budget inside the wake reveals also that the thermal stratification of the incoming wind considerably affects the magnitude and spatial distribution of the turbulent production, transport term and dissipation rate (transfer of energy to the subgrid scales). It is also shown that the near-wake region can be extended to a farther distance downstream in stable condition compared with neutral and unstable counterparts. In order to isolate the effect of atmospheric stability, additional simulations of neutrally-stratified atmospheric boundary layers are performed with the same turbulence intensity at hub height as convective and stable ones. The results show that the

  14. Evaluation of microwave oven heating for prediction of drug-excipient compatibilities and accelerated stability studies

    DEFF Research Database (Denmark)

    Schou-Pedersen, Anne Marie V; Østergaard, Jesper; Cornett, Claus

    2015-01-01

    , if a microwave oven is applicable for accelerated drug stability testing. Chemical interactions were investigated in three selected model formulations of drug and excipients regarding the formation of ester and amide reaction products. The accelerated stability studies performed in the microwave oven using...... a design of experiments (DoE) approach in order to be able to rank excipients regarding reactivity: Study A: cetirizine with PEG 400, sorbitol, glycerol and propylene glycol. Study B: 6-aminocaproic acid with citrate, acetate, tartrate and gluconate. Study C: atenolol with citric, tartaric, malic, glutaric......, and sorbic acid. The model formulations were representative for oral solutions (co-solvents), parenteral solutions (buffer species) and solid dosage forms (organic acids applicable for solubility enhancement). The DoE studies showed overall that the same impurities were generated by microwave oven heating...

  15. Thermogravimetric studies of the thermo- oxidative stability of irradiated and unirradiated polyethylene—II. combined antioxidants

    Science.gov (United States)

    Novaković, Lj.; Gal, O.; Marković, V.; Stannett, V. T.

    In part one of this series the effects of a phenolic, an amine and a thioester antioxidant on the thermo-oxidative stability of irradiated and unirradiated low-density polyethylene was reported. In this paper the effects of combined phenolic and thioester stabilizers are described. Isothermal thermogravimetric analysis was used to study the systems. Pronounced synergism was observed with the induction periods, the time when the initial weight loss begins and the 5% weight loss. At about 50% of each stabilizer increases greater than twofold were observed both with the unirradiated and irradiated polymers. The rate constants for oxygen uptake were decreased. However, the rates of degradation at 5% weight loss fell between the values of the two pure stabilizers with no pronounced synergism in either case. In the absence of oxygen little effect of either antioxidant or their mixtures was observed. The corresponding activation energies were somewhat higher, however, with the irradiated samples containing antioxidants. Dynamic thermogravimetry was used for this study. A kinetic analysis indicated that there were somewhat different modes of degradation at lower- and higher- temperature ranges.

  16. Synthesis and formulation studies of griseofulvin analogues with improved solubility and metabolic stability.

    Science.gov (United States)

    Petersen, Asger B; Andersen, Nikolaj S; Konotop, Gleb; Hanafiah, Nur Hafzan Md; Raab, Marc S; Krämer, Alwin; Clausen, Mads H

    2017-04-21

    Griseofulvin (1) is an important antifungal agent that has recently received attention due to its antiproliferative activity in mammalian cancer cells. Comprehensive SAR studies have led to the identification of 2'-benzyloxy griseofulvin 2, a more potent analogue with low micromolar anticancer potency in vitro. Analogue 2 was also shown to retard tumor growth through inhibition of centrosomal clustering in murine xenograft models of colon cancer and multiple myeloma. However, similar to griseofulvin, compound 2 exhibited poor metabolic stability and aqueous solubility. In order to improve the poor pharmacokinetic properties, 11 griseofulvin analogues were synthesized and evaluated for biological activity and physiological stabilities including SGF, plasma, and metabolic stability. Finally, the most promising compounds were investigated in respect to thermodynamic solubility and formulation studies. The 2'-benzylamine analogue 10 proved to be the most promising compound with low μM in vitro anticancer potency, a 200-fold increase in PBS solubility over compound 2, and with improved metabolic stability. Furthermore, this analogue proved compatible with formulations suitable for both oral and intravenous administration. Finally, 2'-benzylamine analogue 10 was confirmed to induce G2/M cell cycle arrest in vitro. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  17. Nepenthes khasiana mediated synthesis of stabilized gold nanoparticles: Characterization and biocompatibility studies.

    Science.gov (United States)

    Dhamecha, Dinesh; Jalalpure, Sunil; Jadhav, Kiran

    2016-01-01

    The current study summarizes a unique green process for the synthesis of gold nanoparticles by simple treatment of gold salts with aqueous extract of Nepenthes khasiana (NK)--a red listed medicinal plant and its characterization. Study on the effect of different process parameters like temperature, pH and stirring on surface and stability characteristics has been demonstrated. Formation of GNPs was visually observed by change in color from colorless to wine red and characterized by UV-Visible spectroscopy, FT-IR spectroscopy, Zetasizer, X-RD, ICP-AES, SEM-EDAX, AFM and TEM. In vitro stability studies of gold colloidal dispersion in various blood components suggest that, NK mediated GNPs exhibit remarkable in vitro stability in 2% bovine serum albumin, 2% human serum albumin (HSA), 0.2M histidine, and 0.2M cysteine but unstable in 5% NaCl solution and acidic pH. Biocompatibility of NK stabilized GNPs against normal mouse fibroblasts (L929) cell lines revealed nontoxic nature of GNPs and thus provides exceptional opportunities for their uses as nanomedicine for diagnosis and drug therapy. The role of antioxidant phytochemicals (flavonoids and polyphenols) of NK extract in synthesis of biocompatible and stabilized GNPs was demonstrated by estimating total flavonoid content, total phenolic content and total antioxidant capacity of extract before and after formation of GNPs. Fast and easy synthesis of biocompatible GNPs possesses unique physical and chemical features which serve as an advantage for its use in various biomedical applications. The overall approach designated in the present research investigation for the synthesis of GNPs is based on all 12 principles of green chemistry, in which no man-made chemical other than the gold chloride was used. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Wind Turbine and Wind Power Plant Modelling Aspects for Power System Stability Studies

    DEFF Research Database (Denmark)

    Altin, Müfit; Hansen, Anca Daniela; Göksu, Ömer

    2014-01-01

    is not reasonable regarding the focus of the study. Therefore the power system operators should be aware of the modelling aspects of the wind power considering the related stability study and implement the required model in the appropriate power system toolbox. In this paper, the modelling aspects of wind turbines...... and wind power plants are reviewed for power system stability studies. Important remarks of the models are presented by means of simulations to emphasize the impact of these modelling details on the power system.......Large amount of wind power installations introduce modeling challenges for power system operators at both the planning and operational stages of power systems. Depending on the scope of the study, the modeling details of the wind turbine or the wind power plant are required to be different. A wind...

  19. Investigation of the Possibilities for After Harvest Ripening the Fruits of Cape Gooseberry (Physalis peruviana L.) Depending on the Applied Agrotechnology

    OpenAIRE

    PANAYOTOV, Nikolay; POPOVA, Ani

    2015-01-01

    The main goal of the present study was to establish the possibilities for posy-harvest ripening of fruit of cape gooseberry (Physalis peruviana L.). Some part of the cape gooseberry fruit can not ripen until the end of the growing season. Therefore, it is necessary to be carried out the studies in relation with after harvest ripening. This results on an increase in overall productivity. The experiments were carried out with two genotypes of cape gooseberry – first Bulgarian variety Plovdiv an...

  20. Feasibility of Pulse Oximetry Pre-discharge Screening Implementation for detecting Critical Congenital heart Lesions in newborns in a secondary level maternity hospital in the Western Cape, South Africa: The 'POPSICLe' study.

    Science.gov (United States)

    Van Niekerk, A M; Cullis, R M; Linley, L L; Zühlke, L

    2016-07-07

    Early detection of critical congenital heart disease (CCHD) through newborn pulse oximetry (POx) screening is an effective strategy for reducing paediatric morbidity and mortality rates and has been adopted by much of the developed world. To document the feasibility of implementing pre-discharge POx screening in well babies born at Mowbray Maternity Hospital, a busy government hospital in Cape Town, South Africa. Parent and staff acceptance was assessed. We conducted a prospective study of predischarge POx screening in one postnatal ward, following informed parental consent. During the 4-month study period, 1 017 of 2 256 babies discharged (45.1%) were offered POx screening and 1 001 were screened; 94.0% of tests took <3 minutes to perform, 4.3% 3 - 5 minutes and 1.7% >5 minutes. Eighteen patients needed second screens and three required third screens. Only 3.1% protocol errors were made, all without consequence. The vast majority (91.6%) of nursing staff reported insufficient time to perform the study screening in addition to their daily tasks, but ~75% felt that with a full nursing staff complement and if done routinely (not part of a study), pre-discharge POx screening could be successfully instituted at our facility. Over 98% of the mothers had positive comments. Two babies failed screening and required echocardiograms; one was diagnosed with CCHD and the other with neonatal sepsis. The sensitivity and specificity were 50% (95% confidence interval (CI) 1.3 - 98.7%) and 99.9% (95% CI 99.4 - 100%), respectively, with a percentage correct of 99.8%. POx screening was supported and accepted by staff and parents. If there are no nursing staff shortages and if it is done routinely before discharge, not as part of a study, we conclude that POx screening could be implemented successfully without excessive false positives or errors, or any additional burden to cardiology services.

  1. Tunable release of clavam from clavam stabilized gold nanoparticles — Design, characterization and antimicrobial study

    International Nuclear Information System (INIS)

    Manju, V.; Dhandapani, P.; Gurusamy Neelavannan, M.; Maruthamuthu, S.; Berchmans, S.; Palaniappan, A.

    2015-01-01

    A facile one-step approach is developed to synthesize highly stable (up to 6 months) gold nanoparticles (GNPs) using Clavam, pharmaceutical form of amoxicillin which contains a mixture of amoxicillin and potassium salt of clavulanic acid, at room temperature (25–30 °C). The clavam stabilized GNPs are characterized using various techniques including UV–Visible, FT-IR spectrophotometry and transmission electron microscopy (TEM). Tunable release of clavam from clavam stabilized GNPs is demonstrated using intracellular concentrations of glutathione (GSH). The process is monitored using an UV–Vis spectroscopy and the amount of clavam released in terms of amoxicillin concentration is quantitatively estimated using reverse phase high performance liquid chromatographic (RP-HPLC) technique. In vitro study reveals that the clavam released from GNPs' surface was found to show a significant enhancement in antibacterial activity against Escherichia coli and the cause of enhancement is addressed. - Graphical abstract: Stable and nearly monodisperse gold nanoparticles (GNPs) are prepared at room temperature (~ 25–30 °C) using clavam; commercial form of amoxicillin antibiotic. Tunable release of clavam from clavam stabilized GNPs is demonstrated by the addition of varying concentrations of glutathione. Interactions between clavam and gold core are investigated in detail. The mechanism of enhanced antimicrobial activity of clavam released from clavam stabilized GNPs is probed. - Highlights: • Gold nanoparticles (GNPs) are prepared without reducing agent using antibiotic clavam TR . • Our work shed lights on the nature of interaction between the clavam and GNPs. • Sustained release of clavam from clavam stabilized GNPs is demonstrated using glutathione. • Antimicrobial activity of the released clavam is confirmed using various techniques. • Our study suggests that the clavam released from GNPs shows better inhibition of E. coli

  2. Tunable release of clavam from clavam stabilized gold nanoparticles — Design, characterization and antimicrobial study

    Energy Technology Data Exchange (ETDEWEB)

    Manju, V. [Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu 630006 (India); Dhandapani, P. [Corrosion Materials and Protection Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu, 630006 (India); Gurusamy Neelavannan, M. [Characterization and Measurement lab, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu 630006 (India); Maruthamuthu, S. [Corrosion Materials and Protection Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu, 630006 (India); Berchmans, S. [Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu 630006 (India); Palaniappan, A., E-mail: palani112@gmail.com [Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu 630006 (India)

    2015-04-01

    A facile one-step approach is developed to synthesize highly stable (up to 6 months) gold nanoparticles (GNPs) using Clavam, pharmaceutical form of amoxicillin which contains a mixture of amoxicillin and potassium salt of clavulanic acid, at room temperature (25–30 °C). The clavam stabilized GNPs are characterized using various techniques including UV–Visible, FT-IR spectrophotometry and transmission electron microscopy (TEM). Tunable release of clavam from clavam stabilized GNPs is demonstrated using intracellular concentrations of glutathione (GSH). The process is monitored using an UV–Vis spectroscopy and the amount of clavam released in terms of amoxicillin concentration is quantitatively estimated using reverse phase high performance liquid chromatographic (RP-HPLC) technique. In vitro study reveals that the clavam released from GNPs' surface was found to show a significant enhancement in antibacterial activity against Escherichia coli and the cause of enhancement is addressed. - Graphical abstract: Stable and nearly monodisperse gold nanoparticles (GNPs) are prepared at room temperature (~ 25–30 °C) using clavam; commercial form of amoxicillin antibiotic. Tunable release of clavam from clavam stabilized GNPs is demonstrated by the addition of varying concentrations of glutathione. Interactions between clavam and gold core are investigated in detail. The mechanism of enhanced antimicrobial activity of clavam released from clavam stabilized GNPs is probed. - Highlights: • Gold nanoparticles (GNPs) are prepared without reducing agent using antibiotic clavam{sup TR}. • Our work shed lights on the nature of interaction between the clavam and GNPs. • Sustained release of clavam from clavam stabilized GNPs is demonstrated using glutathione. • Antimicrobial activity of the released clavam is confirmed using various techniques. • Our study suggests that the clavam released from GNPs shows better inhibition of E. coli.

  3. Study of locations’characteristics for stabilization of street vendors in Surakarta City

    Science.gov (United States)

    Rahayu, M. J.; Buchori, I.; Widjajanti, R.

    2018-01-01

    Street vendors are usually centered around particular areas where they have made adaptations based on their activities, instead of scattered all over the city. These locations tend to be close to street vendors’ primary activities and consumers, occupy the public lands, and are productive and accessible. The Municipality of Surakarta has managed the street vendors in the form of stabilization and relocation. In Surakarta, there are 24 areas used for stabilization of street vendors varying in characteristics and quantities. This study uses a spatial analysis aiming to explain the characteristics of locations used for stabilization of street vendors and to identify their physical condition and arrangement. Furthermore, all of the research results will be used as the criteria in choosing the new locations that are suitable for the street vendors’ characteristics and consumers’ preference. The results show that the locations are on the roadsides of the neighborhood, local, and secondary collector roads. The traffic conditions in the stabilization areas are ranging from the very busy until relatively busy level since they are close to activities for trade, education, recreation, offices, and settlements.

  4. Application of isotope-labelled compounds in the study of the chemical stability of pesticides

    International Nuclear Information System (INIS)

    Roesseler, M.; Luther, D.; Abendroth, H.C.; Koch, H.

    1980-01-01

    The user of pesticides requires specific biological modes of action from the corresponding commercial products. Impurities and degradation products may cause uncontrollable toxicological reactions. Profound knowledge of the chemical stability of the effective substance in question and its formulations under storage conditions as well as under those of analytical sample preparation and detection is required. Radioisotope labelled effective substances dimethoate and 1-butyl-amino-cyclohexane-phosphonic acid dibutyl ester are used to study storage stability of the pure effective substance and its formulations; effects of selected impurities, such as technical by-products, moisture or water content, binding or carrier materials, organic solvents, chemical stabilizers and other formulation components on storage properties; temperature dependence of storage stability; selection of suitable analytical techniques for quantitative determination of the effective substance without interference effects from any by-product; reduction of the necessary analytical expense; disclosure of sources of error in the application of usual analytical techniques; improvement of possibilities of an immediate and clearer discrimination between types and amounts of compounds in a chemical system consisting of one pesticide and its degradation or reaction products at the beginning and at the end of an experimental or reaction period. Radiochemical analytical techniques, such as radio thin-layer chromatography (also combined with liquid scintillation counting), radio gas chromatography, autoradiography and isotope dilution analysis were used. Results are discussed, especially of experiments on dimethoate and its technical by-products

  5. Stability Study of Sunscreens with Free and Encapsulated UV Filters Contained in Plastic Packaging.

    Science.gov (United States)

    Briasco, Benedetta; Capra, Priscilla; Mannucci, Barbara; Perugini, Paola

    2017-05-31

    Sunscreens play a fundamental role in skin cancer prevention and in protection against photo-aging. UV filters are often photo-unstable, especially in relation to their vehicles and, being lipophilic substances, they are able to interact with plastic packaging. Finally, UV filter stability can be significantly affected by the routine use of the product at high temperatures. This work aims to study the stability of sunscreen formulations in polyethylene packaging. Butyl methoxydibenzoylmethane and octocrylene, both in a free form and as encapsulated filters were chosen as UV filters. Stability evaluations were performed both in the packaging and on the formulations. Moreover, a further two non-destructive techniques, near-infrared (NIR) spectroscopy and a multiple light scattering technique, were also used to evaluate the stability of the formulation. Results demonstrated clearly that all of the pack underwent significant changes in its elastic/plastic behavior and in external color after solar irradiation. From the evaluation of the extractable profile of untreated and treated packaging material an absorption of 2-phenoxyethanol and octocrylene were shown. In conclusion, the results highlighted clearly that a reduction of the UV filter in the formulation packed in high-density polyethylene/low-density polyethylene (HDPE/LDPE) material can occur over time, reducing the protective effect of the product when applied to the skin.

  6. Stability Study of Sunscreens with Free and Encapsulated UV Filters Contained in Plastic Packaging

    Directory of Open Access Journals (Sweden)

    Benedetta Briasco

    2017-05-01

    Full Text Available Sunscreens play a fundamental role in skin cancer prevention and in protection against photo-aging. UV filters are often photo-unstable, especially in relation to their vehicles and, being lipophilic substances, they are able to interact with plastic packaging. Finally, UV filter stability can be significantly affected by the routine use of the product at high temperatures. This work aims to study the stability of sunscreen formulations in polyethylene packaging. Butyl methoxydibenzoylmethane and octocrylene, both in a free form and as encapsulated filters were chosen as UV filters. Stability evaluations were performed both in the packaging and on the formulations. Moreover, a further two non-destructive techniques, near-infrared (NIR spectroscopy and a multiple light scattering technique, were also used to evaluate the stability of the formulation. Results demonstrated clearly that all of the pack underwent significant changes in its elastic/plastic behavior and in external color after solar irradiation. From the evaluation of the extractable profile of untreated and treated packaging material an absorption of 2-phenoxyethanol and octocrylene were shown. In conclusion, the results highlighted clearly that a reduction of the UV filter in the formulation packed in high-density polyethylene/low-density polyethylene (HDPE/LDPE material can occur over time, reducing the protective effect of the product when applied to the skin.

  7. A Pilot Stability Study of Dehydroepiandrosterone Rapid-dissolving Tablets Prepared by Extemporaneous Compounding.

    Science.gov (United States)

    Rush, Steven D; Vernak, Charlene; Zhao, Fang

    2017-01-01

    Dehydroepiandrosterone supplementation is used to treat a variety of conditions. Rapid-dissolving tablets are a relatively novel choice for compounded dehydroepiandrosterone dosage forms. While rapid-dissolving tablets offer ease of administration, there are uncertainties about the physical and chemical stability of the drug and dosage form during preparation and over long-term storage. This study was designed to evaluate the stability of dehydroepiandrosterone rapid-dissolving tablets just after preparation and over six months of storage. The Professional Compounding Centers of America rapid-dissolving tablet mold and base formula were used to prepare 10-mg strength dehydroepiandrosterone rapid-dissolving tablets. The formulation was heated at 100°C to 110°C for 30 minutes, released from the mold, and cooled at room temperature for 30 minutes. The resulting rapid-dissolving tablets were individually packaged in amber blister packs and stored in a stability chamber maintained at 25°C and 60% relative humidity. The stability samples were pulled at pre-determined time points for evaluation, which included visual inspection, tablet weight check, United States Pharmacopeia disintegration test, and stability-indicating high-performance liquid chromatography. The freshly prepared dehydroepiandrosterone rapiddissolving tablets exhibited satisfactory chemical and physical stability. Time 0 samples disintegrated within 40 seconds in water kept at 37°C. The high-performance liquid chromatographic results confirmed that the initial potency was 101.9% of label claim and that there was no chemical degradation from the heating procedure. Over six months of storage, there were no significant changes in visual appearance, physical integrity, or disintegration time for any of the stability samples. The high-performance liquid chromatographic results also indicated that dehydroepiandrosterone rapid-dissolving tablets retained >95% label claim with no detectable degradation

  8. Network structure and thermal stability study of high temperature seal glass

    Science.gov (United States)

    Lu, K.; Mahapatra, M. K.

    2008-10-01

    High temperature seal glass has stringent requirement on glass thermal stability, which is dictated by glass network structures. In this study, a SrO-La2O3-Al2O3-B2O3-SiO2 based glass system was studied using nuclear magnetic resonance, Raman spectroscopy, and x-ray diffraction for solid oxide cell application purpose. Glass structural unit neighboring environment and local ordering were evaluated. Glass network connectivity as well as silicon and boron glass former coordination were calculated for different B2O3:SiO2 ratios. Thermal stability of the borosilicate glasses was studied after thermal treatment at 850 °C. The study shows that high B2O3 content induces BO4 and SiO4 structural unit ordering, increases glass localized inhomogeneity, decreases glass network connectivity, and causes devitrification. Glass modifiers interact with either silicon- or boron-containing structural units and form different devitrified phases at different B2O3:SiO2 ratios. B2O3-free glass shows the best thermal stability among the studied compositions, remaining stable after thermal treatment for 200 h at 850 °C.

  9. Model and in vivo studies on human trunk load partitioning and stability in isometric forward flexions.

    Science.gov (United States)

    Arjmand, N; Shirazi-Adl, A

    2006-01-01

    To resolve the trunk redundancy to determine muscle forces, spinal loads, and stability margin in isometric forward flexion tasks, combined in vivo-numerical model studies was undertaken. It was hypothesized that the passive resistance of both the ligamentous spine and the trunk musculature plays a crucial role in equilibrium and stability of the system. Fifteen healthy males performed free isometric trunk flexions of approximately 40 degrees and approximately 65 degrees +/- loads in hands while kinematics by skin markers and EMG activity of trunk muscles by surface electrodes were measured. A novel kinematics-based approach along with a nonlinear finite element model were iteratively used to calculate muscle forces and internal loads under prescribed measured postures and loads considered in vivo. Stability margin was investigated using nonlinear, linear buckling, and perturbation analyses under various postures, loads and alterations in ligamentous stiffness. Flexion postures significantly increased activity in extensor muscles when compared with standing postures while no significant change was detected in between flexed postures. Compression at the L5-S1 substantially increased from 570 and 771 N in upright posture, respectively, for +/-180 N, to 1912 and 3308 N at approximately 40 degrees flexion, and furthermore to 2332 and 3850 N at approximately 65 degrees flexion. Passive ligamentous/muscle components resisted up to 77% of the net moment. In flexion postures, the spinal stability substantially improved due both to greater passive stiffness and extensor muscle activities so that, under 180 N, no muscle stiffness was required to maintain stability. The co-activity of abdominal muscles and the muscle stiffness were of lesser concern to maintain stability in forward flexion tasks as compared with upright tasks. An injury to the passive system, on one hand, required a substantial compensatory increase in active muscle forces which further increased passive

  10. Influence of extracellular matrix coatings on implant stability and osseointegration: an animal study.

    Science.gov (United States)

    Stadlinger, Bernd; Pilling, Eckart; Huhle, Matthias; Mai, Ronald; Bierbaum, Susanne; Bernhardt, Ricardo; Scharnweber, Dieter; Kuhlisch, Eberhard; Hempel, Ute; Eckelt, Uwe

    2007-10-01

    Aim of the present study was to test the hypothesis that the application of components of the extracellular matrix such as glycosaminoglycans used as implant surface coatings in combination with collagen, with and without growth factor, can lead to enhanced ossification and thus improve implant stability compared with collagen coatings alone. Twenty miniature pigs received 120 experimental titanium implants in the mandible. Three types of surface coatings were created: (1) collagen type I (coll), (2) collagen type I/chondroitin sulphate (coll/CS), (3) collagen type I/chondroitin sulphate/BMP-4 (coll/CS/BMP). Periimplant bone formation was assessed within a defined recess along the length axis of the implant. Bone-implant contact (BIC) and bone volume density (BVD) were determined, using both histomorphometry and synchrotron radiation micro computed tomography (SRmicroCT). To measure implant stability, resonance frequency analysis was applied after implantation and 1, 3, 7, and 22 weeks after placement. BIC was highest for coll/CS coated implants, followed by coll, p = 0.082. Histomorphometric BVD did not significantly change for any coating. SRmicroCT analysis showed an increased BVD for collagen coated implants, compared with the other two surface coatings. Implant stability showed a decrease for all coatings up to the third week. At 22 weeks, all coatings showed an increase in stability without reaching their initial level. Highest stability was reached for coll coated implants, p = 0.051. It was concluded that collagen and coll/CS implant coatings have advantageous characteristics for peri-implant bone formation, compared with the further integration of BMP-4.

  11. Fixation stability of the upward gaze in patients with myasthenia gravis: an eye-tracker study.

    Science.gov (United States)

    Mihara, Miharu; Hayashi, Atsushi; Fujita, Kazuya; Kakeue, Ken; Tamura, Ryoi

    2017-01-01

    To quantify fixation stability of the upward gaze in patients with myasthenia gravis (MG) using an eye tracker. In this study, 21 normal subjects, 5 patients with MG with diplopia, 5 patients with MG without diplopia and 6 patients with superior oblique (SO) palsy were included. Subjects fixated on a target in the upward direction for 1 min. The horizontal (X) and vertical (Y) eye positions were recorded using an eye tracker. Fixation stability was first quantified using the bivariate contour ellipse areas (BCEA) of fixation points as an index of whole stability. Then, the SDs of the X and Y eye positions (SDX and SDY, respectively) were quantified as indices of directional stability, with the data divided into three 20 s fractions to detect temporal fixation fluctuation. BCEAs were larger in patients with MG (both with and without diplopia) than normal subjects and patients with SO palsy, without significant differences among the three 20 s fractions. Compared with normal subjects, SDXs were larger only in patients with MG with diplopia; SDYs were larger in both patients with MG with and without diplopia. In addition, SDYs in patients with MG with diplopia were larger than those in patients with MG without diplopia and patients with SO palsy. Furthermore, a significant difference among the three 20 s fractions was detected for SDYs in patients with MG with diplopia. Patients with MG, especially those with diplopia, exhibit fixation instability in the upward gaze. Non-invasive quantification of fixation stability with an eye tracker is useful for precisely identifying MG-specific fatigue characteristics. UMIN000023468; pre-results.

  12. A Study of Strong Stability of Distributed Systems. Ph.D. Thesis

    Science.gov (United States)

    Cataltepe, Tayfun

    1989-01-01

    The strong stability of distributed systems is studied and the problem of characterizing strongly stable semigroups of operators associated with distributed systems is addressed. Main emphasis is on contractive systems. Three different approaches to characterization of strongly stable contractive semigroups are developed. The first one is an operator theoretical approach. Using the theory of dilations, it is shown that every strongly stable contractive semigroup is related to the left shift semigroup on an L(exp 2) space. Then, a decomposition for the state space which identifies strongly stable and unstable states is introduced. Based on this decomposition, conditions for a contractive semigroup to be strongly stable are obtained. Finally, extensions of Lyapunov's equation for distributed parameter systems are investigated. Sufficient conditions for weak and strong stabilities of uniformly bounded semigroups are obtained by relaxing the equivalent norm condition on the right hand side of the Lyanupov equation. These characterizations are then applied to the problem of feedback stabilization. First, it is shown via the state space decomposition that under certain conditions a contractive system (A,B) can be strongly stabilized by the feedback -B(*). Then, application of the extensions of the Lyapunov equation results in sufficient conditions for weak, strong, and exponential stabilizations of contractive systems by the feedback -B(*). Finally, it is shown that for a contractive system, the first derivative of x with respect to time = Ax + Bu (where B is any linear bounded operator), there is a related linear quadratic regulator problem and a corresponding steady state Riccati equation which always has a bounded nonnegative solution.

  13. Methods study of homogeneity and stability test from cerium oxide CRM candidate

    International Nuclear Information System (INIS)

    Samin; Susanna TS

    2016-01-01

    The methods study of homogeneity and stability test from cerium oxide CRM candidate has been studied based on ISO 13258 and KAN DP. 01. 34. The purpose of this study was to select the test method homogeneity and stability tough on making CRM cerium oxide. Prepared 10 sub samples of cerium oxide randomly selected types of analytes which represent two compounds, namely CeO 2 and La 2 O 3 . At 10 sub sample is analyzed CeO 2 and La 2 O 3 contents in duplicate with the same analytical methods, by the same analyst, and in the same laboratory. Data analysis results calculated statistically based on ISO 13528 and KAN DP.01.34. According to ISO 13528 Cerium Oxide samples said to be homogeneous if Ss ≤ 0.3 σ and is stable if | Xr – Yr | ≤ 0.3 σ. In this study, the data of homogeneity test obtained CeO 2 is Ss = 2.073 x 10-4 smaller than 0.3 σ (0.5476) and the stability test obtained | Xr - Yr | = 0.225 and the price is < 0.3 σ. Whereas for La 2 O 3 , the price for homogeneity test obtained Ss = 1.649 x 10-4 smaller than 0.3 σ (0.4865) and test the stability of the price obtained | Xr - Yr | = 0.2185 where the price is < 0.3 σ. Compared with the method from KAN, a sample of cerium oxide has also been homogenized for Fcalc < Ftable and stable, because | Xi - Xhm | < 0.3 x n IQR. Provided that the results of the evaluation homogeneity and stability test from CeO 2 CRM candidate test data were processed using statistical methods ISO 13528 is not significantly different with statistical methods from KAN DP.01.34, which together meet the requirements of a homogeneous and stable. So the test method homogeneity and stability test based on ISO 13528 can be used to make CRM cerium oxide. (author)

  14. Stability and kinetic studies of supported ionic liquid phase catalysts for hydroformylation of propene

    DEFF Research Database (Denmark)

    Riisager, Anders; Fehrmann, Rasmus; Haumann, Marco

    2005-01-01

    . The activation energy was determined to be 63.3 +/- 2.1 kJ mol(-1), which is in good agreement with known results from biphasic hydroformylation. The results from the kinetic studies confirmed previously published results on the homogeneous nature of the heterogenised Rh-SILP catalyst. Long-term stability......Supported ionic liquid phase (SILP) catalysts have been studied with regard to their long-term stability in the continuous gas-phase hydroformylation of propene. Kinetic data have been acquired by variation of temperature, pressure, syngas composition, substrate concentration, and residence time...... exceeded 200 h time on stream with no loss in selectivity. A small decrease in activity could be compensated by a vacuum procedure regaining the initial activity....

  15. Study of the hydrodynamic stability of natural-circulation steam generators

    International Nuclear Information System (INIS)

    Olive, J.

    1981-01-01

    This report presents a mathematical model of a study of the stability of natural-circulation steam generators. The method used consists in linearizing the equations for the single-dimensional flow and integrating them by using Laplace's transformation. The properties of the two-phase fluids are described by a homegeneous model with slip. The results of the calculation are the transfer functions of the circulation loop and its own oscillation modes (period and damping). Comparison of the results obtained by this method with those from other existing methods in the case of a straight tube with forced flow have proved satisfactory. Lastly, the results of a parametric study on the stability of a natural-circulation steam generator for a PWR unit are presented. The results show that the model is capable of reproducing at least qualitatively the trends observed experimentally or obtained by other more complex theoretical models [fr

  16. Chemical stability and surface stoichiometry of vanadium oxide phases studied by reactive molecular dynamics simulations

    Science.gov (United States)

    Jeon, Byoungseon; Ko, Changhyun; van Duin, Adri C. T.; Ramanathan, Shriram

    2012-02-01

    Compositional stability of various vanadium oxides and oxide growth on vanadium surfaces have been studied using reactive molecular dynamics simulation methods. Vanadium dioxide (VO2), sesquioxide (V2O3), pentoxide (V2O5), and hexavanadium tridecaoxide (V6O13) are studied in bulk crystalline and thin film structures, investigating charge distribution and pair distribution functions of particle interactions. The stability is estimated to be pentoxide, hexavanadium tridecaoxide, sesquioxide, and dioxide respectively in decreasing order in thin film structures. We then analyze oxide growth kinetics on vanadium (100) and (110) surfaces. The oxidation rate, stoichiometry, charge distribution, and the effect of surface orientation on kinetic phenomena are noted. In the early stages of surface oxidation of our simulation configurations, sesquioxide is found to be the dominant component. The modeling and simulation results are compared with experiments where available.

  17. Lyapunov indices and the Poincare mapping in a study of the stability of the krebs cycle

    International Nuclear Information System (INIS)

    Gryrtsay, V.I.

    2015-01-01

    On the basis of a mathematical model, we continue the study of the metabolic Krebs cycle (or the tricarboxylic acid cycle). For the first time, we consider its consistency and stability, which depend on the dissipation of a transmembrane potential formed by the respiratory chain in the plasmatic membrane of a cell. The phase-parametric characteristic of the dynamics of the ATP level depending on a given parameter is constructed. The scenario of formation of multiple autoperiodic and chaotic modes is presented. Poincare sections and mappings are constructed. The stability of modes and the fractality of the obtained bifurcations are studied. The full spectra of Lyapunov indices, divergences, KS-entropies, horizons of predictability, and Lyapunov dimensionalities of strange attractors are calculated. Some conclusions about the structural-functional connections determining the dependence of the cell respiration cyclicity on the synchronization of the functioning of the tricarboxylic acid cycle and the electron transport chain are presented

  18. Activity and stability studies of platinized multi-walled carbon nanotubes as fuel cell electrocatalysts

    DEFF Research Database (Denmark)

    Stamatin, Serban Nicolae; Borghei, Maryam; Dhiman, Rajnish

    2015-01-01

    A non-covalent functionalization for multi-walled carbon nanotubes has been used as an alternative to the damaging acid treatment. Platinum nanoparticles with similar particle size distribution have been deposited on the surface modified multi-walled carbon nanotubes. The interaction between...... platinum nanoparticles and multi-walled carbon nanotubes functionalized with 1-pyrenecarboxylic acid is studied and its electrochemical stability investigated. This study reveals the existence of a platinum-support interaction and leads to three main conclusions. First, the addition of 1-pyrenecarboxylic...... acid is improving the dispersion of platinum nanoparticles, leading to an improved electrochemical activity towards oxygen reduction reaction. Second, the investigations regarding the electrochemical stability showed that the platinum-support interaction plays an important role in improving the long...

  19. A Posteriori Integration of University CAPE Software Developments

    DEFF Research Database (Denmark)

    Tolksdorf, Gregor; Fillinger, Sandra; Wozny, Guenter

    2015-01-01

    This contribution deals with the mutual integration of existing CAPE software products developed at different universities in Germany, Denmark, and Italy. After the motivation MOSAIC is presented as the bridge building the connection between the modelling tool ICAS-MoT and the numerical processing...... tool BzzMath. In the main part a case-study is presented, including descriptions of the benefits, challenges, implementation, and application. This paper is completed with aspects of current research activities and a conclusion summarizing the results....

  20. Learners' experiences of learning support in selected Western Cape schools

    Directory of Open Access Journals (Sweden)

    Olaniyi Bojuwoye

    2014-01-01

    Full Text Available The study explored Western Cape primary and secondary school learners' experiences regarding the provision and utilization of support services for improving learning. A qualitative interpretive approach was adopted and data gathered through focus group interviews involving 90 learners. Results revealed that learners received and utilized various forms of learning support from their schools, teachers, and peers. The learning support assisted in meeting learners' academic, social and emotional needs by addressing barriers to learning, creating conducive learning environments, enhancing learners' self-esteem and improving learners' academic performance.

  1. Assessment of metal contamination in an urban drainage system (using water and tilapia, Oreochromis spp.) in view of human health effect. A case study of some selected communities in Cape Coast township in Ghana

    International Nuclear Information System (INIS)

    Baidoo, I.K.; Opata, N.S.; Sarfo, D.K.; Sarsah, L.A.; Appenteng, M.K.; Kaka, E.A.; Serfor-Armah, Y.

    2012-01-01

    This research work aimed at studying the metal content of water and tilapia fish sample, Oreochromis spp., from a wastewater-fed pond around the University of Cape Coast community using instrumental neutron activation analysis. The metals studied were Al, As, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, V and Zn. In the water samples the order of elemental concentrations at sampling point 1, in μg/g, was K (75.96 ± 0.92), Na (18.52 ± 0.35), Al (6.00 ± 0.89), Mn (3.28 ± 0.44), As (3.08 ± 0.40), Mg (1.56 ± 0.17), Ca (0.70 ± 0.08), Cu (0.54 ± 0.08) and V (0.04 ± 0.01). Co, Cr, Fe and Zn were below detection limits of INAA. The order of elemental concentrations in the water at point 2 was as follows: Na (4.99 ± 0.14), K (4.82 ± 0.89), Mn (4.40 ± 0.53), Mg (2.92 ± 0.37), Al (1.98 ± 0.21), As (0.69 ± 0.10), Ca (0.24 ± 0.07) and V (0.23 ± 0.06) with Co, Cr, Cu, Fe and Zn falling below the detection limit of INAA. The concentrations recorded for Al, As, Cu and Mn in the water samples were all above WHO permissible limits. The mean levels of heavy metals in the soft tissue of tilapia was of the order: K > Mg > Fe > Ca > Na > Al > Mn > Zn > V > Cu > Cr > Co. Arsenic was below detection limit. The transfer factor values calculated for the metals Al, Ca, K, Mg, Mn, Na and V were all greater than one indicating movement of metals from the water column to the tilapia species. The hazard index (HI) calculated for Al, Fe, Mn and V suggested possible occurrence of adverse health effects (HI > 1) where as the HI value obtained for Cr, Cu and Zn (i.e., HI < 1) suggested unlikely adverse effects occurring. (author)

  2. Physical and chemical characterization of active pharmaceutical ingredients in the framework of preformulation and stability studies

    OpenAIRE

    Gana , Inès

    2015-01-01

    The development of a drug for a given therapeutic target requires several steps, which can be summarized by drug screening, a preclinical phase and a number of clinical phases. These steps allow the selection of an active substance and a verification of its therapeutic efficacy and toxicological safety. The latter two criteria define the quality of the drug, which once demonstrated, must be guaranteed throughout its shelf life. Quality is assessed through stability studies that are carried ou...

  3. The Effect of Caffeic Acid Phenethyl Ester (CAPE) Fortification on the Liver Element Distribution that Occurs After Exercise.

    Science.gov (United States)

    Akil, Mustafa; Coban, Funda Karabag; Yalcinkaya, Ozcan

    2016-08-01

    The purpose of this study is to examine the effect of the caffeic acid phenethyl ester (CAPE) fortification applied to the rats, which were made to exercise, on the liver elements. The study was conducted on 32 Sprague-Dawley male rats. The experimental animals were divided into 4 groups in equal numbers. Group 1 is the group which was applied 10 μmol/kg/day CAPE as intraperitoneal (IP) for 4 weeks, and they were not made to exercise at the end of the application. Group 2 is the group which was applied 10 μmol/kg/day CAPE as IP for 4 weeks, and they were made to exercise at the end of the 4th week. Group 3 is the general control group. Group 4 is the swimming control group. A 10 mmol/kg CAPE application dissolved in ethyl alcohol of 10 % was applied to the CAPE group. Sodium (Na), zinc (Zn), calcium (Ca), iron (Fe), chrome (Cr), magnesium (Mg), potassium (K), copper (Cu) and cadmium (Cd) levels were identified in the liver samples at the end of the application. The results of the study suggest that exercise and CAPE fortification in rats cause changes in the Na, Zn, Ca, Fe and Cr parameters in liver tissues, and it does not affect Cd, Cu, Mg and K element distribution. It is thought that CAPE fortification would be helpful for preserving those parameters whose levels are known to be changing with exercise.

  4. Caffeic acid phenethyl ester (CAPE): scavenger of peroxynitrite in vitro and in sepsis models.

    Science.gov (United States)

    Kassim, Mustafa; Mansor, Marzida; Kamalden, Tengku Ain; Shariffuddin, Ina Ismiarti; Hasan, Mohd Shahnaz; Ong, Gracie; Sekaran, Shamala Devi; Suhaimi, Anwar; Al-Abd, Nazeh; Yusoff, Kamaruddin Mohd

    2014-08-01

    Excessive free radical production by immune cells has been linked to cell death and tissue injury during sepsis. Peroxynitrite is a short-lived oxidant and a potent inducer of cell death that has been identified in several pathological conditions. Caffeic acid phenethyl ester (CAPE) is an active component of honeybee products and exhibits antioxidant, anti-inflammatory, and immunomodulatory activities. The present study examined the ability of CAPE to scavenge peroxynitrite in RAW 264.7 murine macrophages stimulated with lipopolysaccharide/interferon-γ that was used as an in vitro model. Conversion of 123-dihydrorhodamine to its oxidation product 123-rhodamine was used to measure peroxynitrite production. Two mouse models of sepsis (endotoxemia and cecal ligation and puncture) were used as in vivo models. The level of serum 3-nitrotyrosine was used as an in vivo marker of peroxynitrite. The results demonstrated that CAPE significantly improved the viability of lipopolysaccharide/interferon-γ-treated RAW 264.7 cells and significantly inhibited nitric oxide production, with effects similar to those observed with an inhibitor of inducible nitric oxide synthase (1400W). In addition, CAPE exclusively inhibited the synthesis of peroxynitrite from the artificial substrate SIN-1 and directly prevented the peroxynitrite-mediated conversion of dihydrorhodamine-123 to its fluorescent oxidation product rhodamine-123. In both sepsis models, CAPE inhibited cellular peroxynitrite synthesis, as evidenced by the absence of serum 3-nitrotyrosine, an in vivo marker of peroxynitrite. Thus, CAPE attenuates the inflammatory responses that lead to cell damage and, potentially, cell death through suppression of the production of cytotoxic molecules such as nitric oxide and peroxynitrite. These observations provide evidence of the therapeutic potential of CAPE treatment for a wide range of inflammatory disorders.

  5. Cape Verdean Notions of Migrant Remittances

    Directory of Open Access Journals (Sweden)

    Lisa Åkesson

    2011-10-01

    Full Text Available The transfer of money from migrants to their non-migrant relatives is a key, symbol of the quality and meaning of transnational kinship relations. This article analyses how people in Cape Verde view migrant family members’ economic obligations and it examines the concomitant moral discourse. Through a detailed ethnographic study the article explores how gender and kinship positions interplay with the moral obligation to send remittances, and it also inquires into the differences between rural and urban people’s attitudes towards monetary gifts. Moreover, the importance of the receiver’s status in the local society is discussed and the role of the personal relation between the sender and the receiver. Thus the analysis goes beyond an instrumental and rationalistic approach to remittances, which is common in much research, and explores the significance of this money for emotions and social relations.Para os seus parentes não emigrantes as remessas dos emigrantes são um símbolo chave da qualidade e do significado das relações de parentesco transnacionais. Este artigo analisa como as pessoas em Cabo Verde encaram as obrigações económicas dos emigrantes membros de família e examina o discurso moral concomitante. Através de um estudo etnográfico detalhado o artigo explora como posições de género e parentesco interagem com a obrigação moral de enviar remessas e também investiga as diferenças entre as atitudes das pessoas rurais e urbanas relativamente às ofertas monetárias. Além disso, discute-se a importância do estatuto do receptor na sociedade local e o papel da relação pessoal entre remetente e receptor. Assim, a análise vai além de uma abordagem instrumental e racionalista das remessas, o que é habitual em muitas pesquisas, explorando o significado deste dinheiro em termos de emoções e relações sociais.

  6. Immediate semi-static loading using compression healing abutments: a stability study in dogs.

    Science.gov (United States)

    Cano, Jorge; Campo, Julián; Colmenero, César; Rodríguez-Vázquez, José Francisco

    2012-08-01

    Loading in implant dentistry to accelerate prosthodontic treatment has been receiving increasing interest. The aim of this study was to investigate the effect of an early controlled lateral loading (after 7 days) on the establishment of osseointegration by means of resonance frequency analysis. Two groups of six beagle dogs each were used. Group I had implants without loading. Group II had implants loaded with a new prototype compression abutment that created controlled semi-static loading. Loaded implants showed slightly better stability after 5 weeks of healing, but the difference was not significant. We concluded that controlled loading is beneficial to maintain, and even improve, stability during the early critical healing period. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. A Study On Dispersion Stability Of Nickel Nanoparticles Synthesized By Wire Explosion In Liquid Media

    Directory of Open Access Journals (Sweden)

    Kim C.K.

    2015-06-01

    Full Text Available In this study, nickel nanoparticles were synthesized in ethanol using portable pulsed wire evaporation, which is a one-step physical method. From transmission electron microscopy images, it was found that the Ni nanoparticles exhibited a spherical shape with an average diameter of 7.3 nm. To prevent aggregation of the nickel nanoparticles, a polymer surfactant was added into the ethanol before the synthesis of nickel nanoparticles, and adsorbed on the freshly synthesized nickel nanoparticles during the wire explosion. The dispersion stability of the prepared nickel nanofluids was investigated by zeta-potential analyzer and Turbiscan optical analyzer. As a result, the optimum concentration of polymer surfactant to be added was suggested for the maximized dispersion stability of the nickel nanofluids.

  8. Study of the relationships between nuclear decontamination foams stability and their physicochemical properties

    International Nuclear Information System (INIS)

    Dame, C.

    2006-03-01

    The LPAD (French Atomic Energy Commission) develops innovative processes in the frame of the future dismantling of nuclear facilities. Formulations were developed using high viscosified foams stabilized by biodegradable nonionic surfactants: alkyl poly-glucosides and viscosifiers (xanthan gum), which allow us to increase the foam lifetime and thus contact time of chemical reactants with the facility walls. We have considered the relationships between physicochemical properties and foam stability through the exploration of the foam at three different scales: from the molecular range (micelles, surface tension and visco-elasticity), to the film and Plateau border range (XR reflectivity, surface shear viscosity) and to macroscopic range, meaning the whole foam (foaminess, liquid fraction and wall film thickness evolution). Finally, exploratory study is presented concerning simultaneous foam three scales characterisation by small angle neutron scattering. (author)

  9. An experimental and numerical study of the atmospheric stability impact on wind turbine wakes

    DEFF Research Database (Denmark)

    Machefaux, Ewan; Larsen, Gunner Chr.; Koblitz, Tilman

    2016-01-01

    In this paper, the impact of atmospheric stability on a wind turbine wake is studied experimentally and numerically. The experimental approach is based on full-scale (nacelle based) pulsed lidar measurements of the wake flow field of a stall-regulated 500 kW turbine at the DTU Wind Energy, Risø...... campus test site. Wake measurements are averaged within a mean wind speed bin of 1 m s1 and classified according to atmospheric stability using three different metrics: the Obukhov length, the Bulk–Richardson number and the Froude number. Three test cases are subsequently defined covering various...... atmospheric conditions. Simulations are carried out using large eddy simulation and actuator disk rotor modeling. The turbulence properties of the incoming wind are adapted to the thermal stratification using a newly developed spectral tensor model that includes buoyancy effects. Discrepancies are discussed...

  10. Timetable stability study on behalf of Swiss Federal Railways; Ziel Puenktlichkeit: Fahrplanstabilitaetsuntersuchung fuer die SBB

    Energy Technology Data Exchange (ETDEWEB)

    Akermann, Hans-Rudolf [SMA und Partner AG, Zuerich (Switzerland); Bueker, Thorsten [RWTH Aachen (Germany). Verkehrswissenschaftliches Inst.

    2008-11-15

    The 2008 annual timetable created new challenges for the Swiss Federal Railways on account of the further intensification of services and the conscious acceptance of stability risks with the entry into service of the Loetschberg Base Tunnel and the upgrading of Interlaken-West to a primary node. To be prepared, the timetable was verified beforehand using stochastic computation techniques at the macroscopic level to examine stability, punctuality and effective achievement of connections. The study succeeded in producing a model of the passenger network that was close to reality, and plausible answers were also provided for the questions asked. Applying this technique to one of the world's densest networks also produced valuable findings that can now be used as meaningful inputs for the further development of the algorithms. (orig.)

  11. Immediatevsnon-immediate loading post-extractive implants: a comparative study of implant stability quotient (ISQ).

    Science.gov (United States)

    Milillo, L; Fiandaca, C; Giannoulis, F; Ottria, L; Lucchese, A; Silvestre, F; Petruzzi, M

    2016-01-01

    This study aims to evaluate differences in implant stability between post-extractive implants vs immediately placed post-extractive implants by resonance frequency analysis (RFA). Patients were grouped into two different categories. In Group A 10 patients had an immediate post-extractive implant, then a provisional, acrylic resin crown was placed (immediate loading). In Group B (control group) 10 patients only had an immediate post-extractive implant. Both upper and lower premolars were chosen as post-extractive sites. Implant Stability Quotient (ISQ) was measured thanks to RFA measurements (Osstell®). Five intervals were considered: immediately after surgery (T0) and every four weeks, until five months after implant placement (T1, T2, T3, T4,T5). A statistical analysis by means of Student's T-test (significance set at pimmediate prosthetic surgery in post-extraction sites with cone-shaped implants, platform-switching abutment and bioactive surface can facilitate osseointegration, reducing healing time.

  12. SERS studies on the interaction between UO22+ and PVP-stabilized silver nanoparticles

    International Nuclear Information System (INIS)

    Roy, M.; Tyagi, A.K.; Kumar, Rakesh; Pandey, A.K.; Goswami, A.

    2010-01-01

    Interaction between uranyl (UO 2 2+ ) ions and silver nanoparticles (Ag-nps) stabilized by suitable polymeric capping agents has been studied in aqueous phase using surface enhanced resonance Raman spectroscopy technique (SERS). Polyvinylpyrrolidone (PVP) stabilized Ag-nps were synthesized by dissolving in water appropriate amount of PVP and AgNO 3 along with a suitable reducing agent in the form of either formamide or sodium borohydride. The solution was vigorously stirred for 5h and finally nanoparticle sols were obtained. A series of analyte samples was prepared by adding an appropriate amount of silver sol to different volumes of uranyl stock solution prepared at pH=3. The solutions were then drop cast on glass slides and dried in air. Preliminary results on drop-cast samples are presented here

  13. A study on the operational stability of a refrigeration system having a variable speed compressor

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yiming; Deng, Shiming; Xu, Xiangguo; Chan, Mingyin [Department of Building Services Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR (China)

    2008-12-15

    The increased use of variable speed compressors (VSC) in refrigeration systems can potentially lead to the unstable operation when compressor speed is varied from time to time for capacity control. The causes of unstable operation may be classified into two groups, one relating to control algorithms and the other to the inherent characteristics of systems. This paper reports on a study on the operational stability of a VSC refrigeration system due to its inherent characteristics. Based on experimental results, a new modified minimal stable superheat (MSS) line having a maximum MSS value and a minimal MSS value has been proposed. Using the modified MSS line, and supported by a series of purposely designed experiments, a detailed analysis on the operational stability of a VSC refrigeration system due to its inherent characteristics when its compressor speed is changed for capacity control has been carried out and presented. (author)

  14. Formulation design of oral pediatric Acetazolamide suspension: dose uniformity and physico-chemical stability study.

    Science.gov (United States)

    Santoveña, Ana; Suárez-González, Javier; Martín-Rodríguez, Cristina; Fariña, José B

    2017-03-01

    The formulation of an active pharmaceutical ingredient (API) as oral solution or suspension in pediatrics is a habitual practice, due to the non-existence of many commercialized medicines in pediatric doses. It is also the simplest way to prepare and administer them to this vulnerable population. The design of a formulation that assures the dose and the system stability depends on the physico-chemical properties of the API. In this study, we formulate a class IV API, Acetazolamide (AZM) as suspension for oral administration to pediatric population. The suspension must comply attributes of quality, safety and efficacy for this route of administration. We use simple compounding procedures, as well as fewer pure excipients, as recommended for children. Mass and uniformity content assays and physical and chemical stability studies were performed. To quantify the API an UPLC method was used. We verified the physico-chemical stability of the suspensions and that they passed the mass test of the European Pharmacopeia (EP), but not the dose uniformity test. This reveals that AZM must be formulated as liquid forms with a more complex system of excipients (not usually indicated in pediatrics), or otherwise solid forms capable of assuring uniformity of mass and dose for every dosage unit.

  15. Study of the stability of organic ligands usable for the spent nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    Draye, Micheline

    1994-01-01

    The first part of this research thesis on the stability of organic ligands in radioactive environment, reports the study of the stability of the dicyclohexano-18-crown-6 (DCH18C6) in radioactive environment by using several analytical techniques (nuclear magnetic resonance or NMR, X-ray diffraction, Fourier transform infrared spectroscopy or FTIR, gas chromatography or GC, and coupled gas chromatography/mass spectroscopy). The seven main radiolysis products of DCH18C6 are identified and then synthesised to be tested in radioactive environment. These products are soluble in nitric medium, and partially precipitate plutonium, but cannot in any case disturb the reprocessing process based on a continuous extraction system. Chemical yields are computed and DCH18C6 appears to be a serious candidate for the reprocessing of spent nuclear fuels. The second part reports the study of the stability of the poly(4-vinylpyridine) or P4VP in radioactive environment. It appears that gamma radiations produce radicals in the P4VP which recombine in function of the irradiation dose. However, this material is very stable in acid environment and radioactive environment [fr

  16. Comparative study of different techniques of composting and their stability evaluation in municipal solid waste

    International Nuclear Information System (INIS)

    Iqbal, M.K.; Khan, R.A.; Nadeem, A.; Hussnain, A.

    2012-01-01

    Spatial differences in the physical and chemical characteristics related to maturity of composted organic matter are strongly influenced by composting methods. For evaluation of compost maturity three locally fabricated composters (aerobic, mixed type, anaerobic) processes were examined at seven days interval up to 91 days by loading MSW along with bulking agent. Gradual changes in physico chemical characteristics (temperature, pH, moisture, CEC, humification) related to stability and maturity of compost were studied and compared. Increase in ammonia nitrogen level due to rise in temperature was maximum in aerobic process. Substantial increase in CEC in aerobic process was earlier which leads to establish the optimal degree of maturity as compared to other processes. FA and HI decrease rapidly as composting progressed. Optimal level in stability and maturity parameters like C:N, HA, DH and HR were attained earlier in aerobic process as compared to mixed type and anaerobic processes due to continuous aeration. The parameters (HR, DH, FA, HA), which indicate the compost stability were correlated among themselves. The parameters defining maturity such as CEC, ammonia nitrate and C:N ratio were also related to above mention parameters. The compost from the aerobic process provided good humus and micro nutrients. Result from this study will assist in method optimization and quality of the compost product. (author)

  17. Tangential Bicortical Locked Fixation Improves Stability in Vancouver B1 Periprosthetic Femur Fractures: A Biomechanical Study.

    Science.gov (United States)

    Lewis, Gregory S; Caroom, Cyrus T; Wee, Hwabok; Jurgensmeier, Darin; Rothermel, Shane D; Bramer, Michelle A; Reid, John Spence

    2015-10-01

    The biomechanical difficulty in fixation of a Vancouver B1 periprosthetic fracture is purchase of the proximal femoral segment in the presence of the hip stem. Several newer technologies provide the ability to place bicortical locking screws tangential to the hip stem with much longer lengths of screw purchase compared with unicortical screws. This biomechanical study compares the stability of 2 of these newer constructs to previous methods. Thirty composite synthetic femurs were prepared with cemented hip stems. The distal femur segment was osteotomized, and plates were fixed proximally with either (1) cerclage cables, (2) locked unicortical screws, (3) a composite of locked screws and cables, or tangentially directed bicortical locking screws using either (4) a stainless steel locking compression plate system with a Locking Attachment Plate (Synthes) or (5) a titanium alloy Non-Contact Bridging system (Zimmer). Specimens were tested to failure in either axial or torsional quasistatic loading modes (n = 3) after 20 moderate load preconditioning cycles. Stiffness, maximum force, and failure mechanism were determined. Bicortical constructs resisted higher (by an average of at least 27%) maximum forces than the other 3 constructs in torsional loading (P steel construct in axial loading. Proximal fixation stability is likely improved with the use of bicortical locking screws as compared with traditional unicortical screws and cable techniques. In this study with a limited sample size, we found the addition of cerclage cables to unicortical screws may not offer much improvement in biomechanical stability of unstable B1 fractures.

  18. Synthesis, Antibacterial and Thermal Studies of Cellulose Nanocrystal Stabilized ZnO-Ag Heterostructure Nanoparticles

    Directory of Open Access Journals (Sweden)

    Mohd Zobir Hussein

    2013-05-01

    Full Text Available Synthesis of ZnO-Ag heterostructure nanoparticles was carried out by a precipitation method with cellulose nanocrystals (CNCs as a stabilizer for antimicrobial and thermal studies. ZnO-Ag nanoparticles were obtained from various weight percentages of added AgNO3 relative to Zn precursors for evaluating the best composition with enhanced functional properties. The ZnO-Ag/CNCs samples were characterized systematically by TEM, XRD, UV, TGA and DTG. From the TEM studies we observed that ZnO-Ag heterostructure nanoparticles have spherical shapes with size diameters in a 9–35 nm range. The antibacterial activities of samples were assessed against the bacterial species Salmonella choleraesuis and Staphylococcus aureus. The CNC-stabilized ZnO-Ag exhibited greater bactericidal activity compared to cellulose-free ZnO-Ag heterostructure nanoparticles of the same particle size. The incorporation of ZnO-Ag hetreostructure nanoparticles significantly increased the thermal stability of cellulose nanocrystals.

  19. A comparative study of stabilizing control of a planer electromagnetic levitation using PID and LQR controllers

    Directory of Open Access Journals (Sweden)

    Mundher H.A. Yaseen

    Full Text Available Magnetic levitation is a technique to suspend an object without any mechanical support. The main objective of this study is to demonstrate stabilized closed loop control of 1-DOF Maglev experimentally using real-time control simulink feature of (SIMLAB microcontroller. Proportional Integral Derivative (PID and Linear Quadratic Regulator (LQR controllers are employed to examine the stability performance of the Maglev control system under effect of unbalanced change of load and wave signal on Maglev plane. The effect of unbalanced change of applied load on single point, line and plane are presented. Furthermore, in order to study the effect of sudden change in input signal, the input of wave signal has been applied on all points of the prototype maglev plate simultaneously. The results of pulse width modulation (PWM reveal that the control system using LQR controller provides faster response to adjust the levitated plane comparing to PID controller. Moreover, the air gap distance that controlled using PID controller is rather stable with little oscillation. Meanwhile, LQR controller provided more stability and homogeneous response. Keywords: Magnetic levitation (Maglev, Linear Quadratic Regulator (LQR, PID controller, SIMLAB Platform

  20. Studies of neutron-rich nuclei far from stability at TRISTAN

    International Nuclear Information System (INIS)

    Gill, R.L.

    1984-01-01

    The ISOL facility, TRISTAN, is a user facility located at Brookhaven National Laboratory's High Flux Beam Reactor. Short-lived, neutron-rich nuclei, far from stability, are produced by thermal neutron fission of 235 U. An extensive array of experimental end stations are available for nuclear structure studies. These studies are augmented by a variety of long-lived ion sources suitable for use at a reactor facility. Some recent results at TRISTAN are presented as examples of using an ISOL facility to study series of nuclei, whereby an effective means of conducting nuclear structure investigations is available

  1. Contribution of the Pubofemoral Ligament to Hip Stability: A Biomechanical Study.

    Science.gov (United States)

    Martin, Hal D; Khoury, Anthony N; Schröder, Ricardo; Johnson, Eric; Gómez-Hoyos, Juan; Campos, Salvador; Palmer, Ian J

    2017-02-01

    To determine the isolated function of the pubofemoral ligament of the hip capsule and its contribution to hip stability in external/internal rotational motion during flexion greater than 30° and abduction. Thirteen hips from 7 fresh-frozen pelvis-to-toe cadavers were skeletonized from the lumbar spine to the distal femur with the capsular ligaments intact. Computed tomographic imaging was performed to ensure no occult pathological state existed, and assess bony anatomy. Specimens were placed on a surgical table in supine position with lower extremities resting on a custom-designed polyvinylchloride frame. Hip internal and external rotation was measured with the hip placed into a combination of the following motions: 30°, 60°, 110° hip flexion and 0°, 20°, 40° abduction. Testing positions were randomized. The pubofemoral ligament was released and measurements were repeated, followed by releasing the ligamentum teres. Analysis of the 2,106 measurements recorded demonstrates the pubofemoral ligament as a main controller of hip internal rotation during hip flexion beyond 30° and abduction. Hip internal rotation was increased up to 438.9% (P ligament was released and 412.9% (P ligament were released, compared with the native state. The hypothesis of the pubofemoral ligament as one of the contributing factors of anterior inferior hip stability by controlling external rotation of the hip in flexion beyond 30° and abduction was disproved. The pubofemoral ligament maintains a key function in limiting internal rotation in the position of increasing hip flexion beyond 30° and abduction. This cadaveric study concludes previous attempts at understanding the anatomical and biomechanical function of the capsular ligaments and their role in hip stability. The present study contributes to the understanding of hip stability and biomechanical function of the pubofemoral ligament. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All

  2. Evaluation of microwave oven heating for prediction of drug-excipient compatibilities and accelerated stability studies.

    Science.gov (United States)

    Schou-Pedersen, Anne Marie V; Østergaard, Jesper; Cornett, Claus; Hansen, Steen Honoré

    2015-05-15

    Microwave ovens have been used extensively in organic synthesis in order to accelerate reaction rates. Here, a set up comprising a microwave oven combined with silicon carbide (SiC) plates for the controlled microwave heating of model formulations has been applied in order to investigate, if a microwave oven is applicable for accelerated drug stability testing. Chemical interactions were investigated in three selected model formulations of drug and excipients regarding the formation of ester and amide reaction products. In the accelerated stability studies, a design of experiments (DoE) approach was applied in order to be able to rank excipients regarding reactivity: Study A: cetirizine with PEG 400, sorbitol, glycerol and propylene glycol. Study B: 6-aminocaproic acid with citrate, acetate, tartrate and gluconate. Study C: atenolol with citric, tartaric, malic, glutaric, and sorbic acid. The model formulations were representative for oral solutions (co-solvents), parenteral solutions (buffer species) and solid dosage forms (organic acids applicable for solubility enhancement). The DoE studies showed overall that the same impurities were generated by microwave oven heating leading to temperatures between 150°C and 180°C as compared to accelerated stability studies performed at 40°C and 80°C using a conventional oven. Ranking of the reactivity of the excipients could be made in the DoE studies performed at 150-180°C, which was representative for the ranking obtained after storage at 40°C and 80°C. It was possible to reduce the time needed for drug-excipient compatibility testing of the three model formulations from weeks to less than an hour in the three case studies. The microwave oven is therefore considered to be an interesting alternative to conventional thermal techniques for the investigation of drug-excipient interactions during preformulation. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Association analysis for disease resistance to Fusarium oxysporum in cape gooseberry (Physalis peruviana L).

    Science.gov (United States)

    Osorio-Guarín, Jaime A; Enciso-Rodríguez, Felix E; González, Carolina; Fernández-Pozo, Noé; Mueller, Lukas A; Barrero, Luz Stella

    2016-03-18

    Vascular wilt caused by Fusarium oxysporum is the most important disease in cape gooseberry (Physalis peruviana L.) in Colombia. The development of resistant cultivars is considered one of the most cost-effective means to reduce the impact of this disease. In order to do so, it is necessary to provide breeders with molecular markers and promising germplasm for introgression of different resistance loci as part of breeding schemes. Here we described an association mapping study in cape gooseberry with the goal to: (i) select promising materials for use in plant breeding and (ii) identify SNPs associated with the cape gooseberry resistance response to the F. oxysporum pathogen under greenhouse conditions, as potential markers for cape gooseberry breeding. We found a total of 21 accessions with different resistance responses within a diversity panel of 100 cape gooseberry accessions. A total of 60,663 SNPs were also identified within the same panel by means of GBS (Genotyping By Sequencing). Model-based population structure and neighbor-joining analyses showed three populations comprising the cape gooseberry panel. After correction for population structure and kinship, we identified SNPs markers associated with the resistance response against F. oxysporum. The identification of markers was based on common tags using the reference genomes of tomato and potato as well as the root/stem transcriptome of cape gooseberry. By comparing their location with the tomato genome, 16 SNPs were found in genes involved in defense/resistance response to pathogens, likewise when compared with the genome of potato, 12 markers were related. The work presented herein provides the first association mapping study in cape gooseberry showing both the identification of promising accessions with resistance response phenotypes and the identification of a set of SNP markers mapped to defense/resistance response genes of reference genomes. Thus, the work also provides new knowledge on candidate

  4. Stability, protein binding and clearance studies of [99mTc]DTPA. Evaluation of a commercially available dry-kit

    DEFF Research Database (Denmark)

    Rehling, M

    1988-01-01

    the quality of a commercial [99mTc]DTPA preparation (C.I.S., France) with reference to stability, protein binding and accuracy of the determined plasma clearance values as a measure of GFR. The stability of the preparations was studied by thin-layer chromatography, the in vitro protein binding by Sephadex...

  5. Genetic Moderation of Stability in Attachment Security from Early Childhood to Age 18 Years: A Replication Study

    Science.gov (United States)

    Raby, K. Lee; Roisman, Glenn I.; Booth-LaForce, Cathryn

    2015-01-01

    A longstanding question for attachment theory and research is whether genetically based characteristics of the child influence the development of attachment security and its stability over time. This study attempted to replicate and extend recent findings indicating that the developmental stability of attachment security is moderated by oxytocin…

  6. Torsional stability of interference screws derived from bovine bone - a biomechanical study

    Directory of Open Access Journals (Sweden)

    Schmitt Jan

    2010-05-01

    Full Text Available Abstract Background In the present biomechanical study, the torsional stability of different interference screws, made of bovine bone, was tested. Interference screws derived from bovine bone are a possible biological alternative to conventional metallic or bioabsorbable polymer interference screws. Methods In the first part of the study we compared the torsional stability of self-made 8 mm Interference screws (BC and a commercial 8 mm interference screw (Tutofix®. Furthermore, we compared the torsional strength of BC screws with different diameters. For screwing in, a hexagon head and an octagon head were tested. Maximum breaking torques in polymethyl methacrylate resin were recorded by means of an electronic torque screw driver. In the second part of the study the tibial part of a bone-patellar tendon-bone graft was fixed in porcine test specimens using an 8 mm BC screw and the maximum insertion torques were recorded. Each interference screw type was tested 5 times. Results There was no statistically significant difference between the different 8 mm interference screws (p = 0.121. Pairwise comparisons did not reveal statistically significant differences, either. It was demonstrated for the BC screws, that a larger screw diameter significantly leads to higher torsional stability (p = 9.779 × 10-5. Pairwise comparisons showed a significantly lower torsional stability for the 7 mm BC screw than for the 8 mm BC screw (p = 0.0079 and the 9 mm BC screw (p = 0.0079. Statistically significant differences between the 8 mm and the 9 mm BC screw could not be found (p = 0.15. During screwing into the tibial graft channel of the porcine specimens, insertion torques between 0.5 Nm and 3.2 Nm were recorded. In one case the hexagon head of a BC screw broke off during the last turn. Conclusions The BC screws show comparable torsional stability to Tutofix® interference screws. As expected the torsional strength of the screws increases significantly with the

  7. Torsional stability of interference screws derived from bovine bone - a biomechanical study

    Science.gov (United States)

    2010-01-01

    Background In the present biomechanical study, the torsional stability of different interference screws, made of bovine bone, was tested. Interference screws derived from bovine bone are a possible biological alternative to conventional metallic or bioabsorbable polymer interference screws. Methods In the first part of the study we compared the torsional stability of self-made 8 mm Interference screws (BC) and a commercial 8 mm interference screw (Tutofix®). Furthermore, we compared the torsional strength of BC screws with different diameters. For screwing in, a hexagon head and an octagon head were tested. Maximum breaking torques in polymethyl methacrylate resin were recorded by means of an electronic torque screw driver. In the second part of the study the tibial part of a bone-patellar tendon-bone graft was fixed in porcine test specimens using an 8 mm BC screw and the maximum insertion torques were recorded. Each interference screw type was tested 5 times. Results There was no statistically significant difference between the different 8 mm interference screws (p = 0.121). Pairwise comparisons did not reveal statistically significant differences, either. It was demonstrated for the BC screws, that a larger screw diameter significantly leads to higher torsional stability (p = 9.779 × 10-5). Pairwise comparisons showed a significantly lower torsional stability for the 7 mm BC screw than for the 8 mm BC screw (p = 0.0079) and the 9 mm BC screw (p = 0.0079). Statistically significant differences between the 8 mm and the 9 mm BC screw could not be found (p = 0.15). During screwing into the tibial graft channel of the porcine specimens, insertion torques between 0.5 Nm and 3.2 Nm were recorded. In one case the hexagon head of a BC screw broke off during the last turn. Conclusions The BC screws show comparable torsional stability to Tutofix® interference screws. As expected the torsional strength of the screws increases significantly with the diameter. The safety

  8. Research of quality values and stability study of vaginal suppositories containing fluconazole and chlorhexidine digluconate

    Directory of Open Access Journals (Sweden)

    Катерина Олександрівна Бур’ян

    2015-10-01

    Full Text Available Aim of research. Stability is one of the main quality values of remedies. Biopharmaceutical properties of drugs and efficiency of pharmacodynamic and pharmacokinetic processes of active compounds in human’s organism completely depend on physico-chemical values permanence and microbiological stability of every unit of drug. The aim of research resulting in the article was to determine the main quality values stability and microbiological purity of vaginal suppositories containing fluconazole and chlorhexidine digluconate after storage under certain conditions.Materials and methods. During both storage under room temperature and keeping in cool place vaginal suppositories prepared upon hydrophilic basis were periodically verified on indicators of description, identification, average weight and homogeneity of weight, dissolution, microbiological purity and active ingredients assay in unit dose. All research tests were carried out in accordance with both the SPhU requirements and elaborated draft of quality control procedures for «Flugedyn» remedy.Results. As a result of quality values study of suppositories test samples the efficiency and reliability of developed techniques and normative documentation draft of remedy were confirmed. Samples have been kept for as long as 5 years don’t comply with the requirements of normative documentation of remedy.Conclusion. Thus, summation of research data allow recommend following optimal storage period for vaginal suppositories «Flugedyn»: keep 3 years in dry place at a temperature 2 to 25 оС

  9. Nonlinear stability and control study of highly maneuverable high performance aircraft

    Science.gov (United States)

    Mohler, R. R.

    1993-01-01

    This project is intended to research and develop new nonlinear methodologies for the control and stability analysis of high-performance, high angle-of-attack aircraft such as HARV (F18). Past research (reported in our Phase 1, 2, and 3 progress reports) is summarized and more details of final Phase 3 research is provided. While research emphasis is on nonlinear control, other tasks such as associated model development, system identification, stability analysis, and simulation are performed in some detail as well. An overview of various models that were investigated for different purposes such as an approximate model reference for control adaptation, as well as another model for accurate rigid-body longitudinal motion is provided. Only a very cursory analysis was made relative to type 8 (flexible body dynamics). Standard nonlinear longitudinal airframe dynamics (type 7) with the available modified F18 stability derivatives, thrust vectoring, actuator dynamics, and control constraints are utilized for simulated flight evaluation of derived controller performance in all cases studied.

  10. Preparation, homogeneity and stability studies of a candidate LRM for Se speciation

    Energy Technology Data Exchange (ETDEWEB)

    Bodo, Erzsebet Tuende; Stefanka, Zsolt; Ipolyi, Ildiko; Soeroes, Csilla; Dernovics, Mihaly; Fodor, Peter [Department of Applied Chemistry, Faculty of Food Science, Szent Istvan University, Villanyi ut 29-33, 1118, Budapest (Hungary)

    2003-09-01

    A laboratory reference material (LRM) was prepared from Brazil nuts (Bertholletia excelsa) for quality control (QC) purposes of selenium speciation. The preparation of this LRM led through the usual operation steps applied during routine reference material production from biota samples - preparation of the raw material, homogenisation, storage design, checking of homogeneity, microbiological status and possible irradiation effects, and monitoring the species stability vs time at different storage temperatures. The selenium speciation studies to check species stability were carried out on a HPLC-UV-HG-AFS measurement set-up. Special attention was paid to the correct identification of selenium species by applying independent HPLC separation techniques (ion-pairing and anion-exchange chromatography). The concentration of selenomethionine (SeMet) and total Se content were quantified (79.9 {mu}g g{sup -1} (calculated as Se) and 82.9 {mu}g g{sup -1}, respectively). The homogeneity and stability of this candidate reference material passed the relevant tests recommended by Bureau Communautaire de Reference (BCR). (orig.)

  11. Micromagnetic study of skyrmion stability in confined magnetic structures with perpendicular anisotropy

    Science.gov (United States)

    Novak, R. L.; Garcia, F.; Novais, E. R. P.; Sinnecker, J. P.; Guimarães, A. P.

    2018-04-01

    Skyrmions are emerging topological spin structures that are potentially revolutionary for future data storage and spintronics applications. The existence and stability of skyrmions in magnetic materials is usually associated to the presence of the Dzyaloshinskii-Moriya interaction (DMI) in bulk magnets or in magnetic thin films lacking inversion symmetry. While some methods have already been proposed to generate isolated skyrmions in thin films with DMI, a thorough study of the conditions under which the skyrmions will remain stable in order to be manipulated in an integrated spintronic device are still an open problem. The stability of such structures is believed to be a result of ideal combinations of perpendicular magnetic anisotropy (PMA), DMI and the interplay between geometry and magnetostatics. In the present work we show some micromagnetic results supporting previous experimental observations of magnetic skyrmions in spin-valve stacks with a wide range of DMI values. Using micromagnetic simulations of cobalt-based disks, we obtain the magnetic ground state configuration for several values of PMA, DMI and geometric parameters. Skyrmion numbers, corresponding to the topological charge, are calculated in all cases and confirm the occurrence of isolated, stable, axially symmetric skyrmions for several combinations of DMI and anisotropy constant. The stability of the skyrmions in disks is then investigated under magnetic field and spin-polarized current, in finite temperature, highlighting the limits of applicability of these spin textures in spintronic devices.

  12. Spectral, morphological and antibacterial studies of β-cyclodextrin stabilized silver - Chitosan nanocomposites

    Science.gov (United States)

    Punitha, N.; Ramesh, P. S.; Geetha, D.

    2015-02-01

    The aim of the study is to investigate the antibacterial properties and characterization of β-cyclodextrin (β-CD) stabilized silver - chitosan nanocomposite (Ag-Cts NCs). An effective and eco-friendly technique for the synthesis of Ag-Cts NCs in the presence of a strong stabilizing agent β-CD is described. The well formed nanocomposites were characterized by the Ultraviolet Visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Photoluminescence spectroscopy (PL), Scanning electron microscope (SEM/EDS), Atomic force microscope (AFM), High resolution transmission electron microscope (HR-TEM) and Zeta potential measurement (ZP). The results confirmed that the poly dispersed Ag-Cts NCs are less than 15 nm in size with spherical shape and show good stability. The antibacterial activity was also investigated and β-CD coated Ag-Cts NCs showed a promising bacterial activity against gram negative Escherichia coli (E. coli) and gram positive Staphylococcus aureus (S. aureus) micro-organism.

  13. A THEORETICAL AND NUMERICAL STUDY OF THERMOSOLUTAL CONVECTION: STABILITY OF A SALINITY GRADIENT SOLAR POND

    Directory of Open Access Journals (Sweden)

    Djamel Kalache

    2011-01-01

    Full Text Available A theoretical and numerical study of the effect of thermodiffusion on the stability of a gradient layer is presented. It intends to clarify the mechanisms of fluid dynamics and the processes which occur in a salinity gradient solar pond. A mathematical modelling is developed to describe the thermodiffusion contribution on the solar pond where thermal, radiative, and massive fluxes are coupled in the double diffusion. More realistic boundary conditions for temperature and concentration profiles are used. Our results are compared with those obtained experimentally by authors without extracting the heat flux from the storage zone. We have considered the stability analysis of the equilibrium solution. We assumed that the perturbation of quantities such as velocity, temperature, and concentration are infinitesimal. Linearized equations satisfying appropriate prescribed boundary conditions are then obtained and expanded into polynomials form. The Galerkin method along with a symbolic algebra code (Maple are used to solve these equations. The effect of the separation coefficient y is analyzed in the positive and negative case. We have also numerically compared the critical Rayleigh numbers for the onset of convection with those obtained by the linear stability analysis for Le = 100, µa = 0.8, and f = 0.5.

  14. The Study on Stability and Seakeeping Characteristics of the Glass Bottom Boat Trimaran in Karimunjawa Island

    Science.gov (United States)

    Arswendo Adietya, Berlian; Windyandari, Aulia; Fauzan Zakki, Ahmad

    2018-03-01

    Recently the diversity of fish populations in the waters Karimunjawa Island is only appreciated by those who have the ability to play diving and snorkeling. It is due to the unavailability of a vehicle that is specially made to delight in the fascination of the underwater panorama. One of the alternative solutions is using the glass bottom boat technology which is using transparent bottom that might look out the underwater scenery instead of swimming and snorkeling. The paper has focused on the study of intact stability and seakeeping characteristics of glass bottom boat trimaran in Karimunjawa Island. The intact stability characteristics will be investigated at the various load cases and weight distribution configurations which are influenced by the passenger positions and fuel tank condition. Regarding the seakeeping performance analysis, the ITTC-Bretschneider will be adopted as the wave spectrum at the wave parameters defined from the operational environment. The influence of the parameters on the stability and seakeeping of the glass bottom boat trimaran are presented and discussed.

  15. Study on thermal stability and chemical structure of polyamide blended with small amount of Cu

    International Nuclear Information System (INIS)

    Arai, Tsuyoshi; Ueno, Tomonaga; Kajiya, Takafumi; Ishikawa, Tomoyuki; Takeda, Kunihiko

    2007-01-01

    The thermal stability and the chemical structure of Polyamide 66 (PA66) blended with a small amount of copper have been studied. The thermal degradation of the blend with 35 ppm or more of copper was restrained and no strong influence of the concentration of copper was observed. The molecular weight of PA66 decreased by the thermal aging process but the amount of decrease of the blend was smaller than that of the non-blend. The water uptake of the blend increased. The chemical structure, which was observed by IR and NMR, changed slightly by blending with copper after aging at higher temperatures. Multiple items influenced the thermal stability of PA66 blended with a small amount of copper instead of just one. Namely, the main chain of PA66 is cut by heat and the degree of the cut is restrained by the copper. The diffusion time of copper atoms that disperse uniformly in the PA66 matrix is short enough to cover the individual amide groups and the effect enlarges the entire configuration of the PA66 chain to enhance the thermal stability. (author)

  16. Computer Simulation Study of the Stability Mechanism of Thermophile, MJ0305

    Science.gov (United States)

    Song, Hyundeok; Beck, Thomas

    2011-04-01

    Methanococcus jannaschii (MJ) is a methane-producing thermophile, which was discovered in a 2600m-deep Pacific Ocean vent in 1983. It has the ability to thrive at high temperatures and high pressures, which are unfavorable for most life forms. There have been some experiments to study its stability under extreme conditions, but still the origin of the stability of MJ is not exactly known. MJ0305 is MJ's chloride channel protein. The structure of MJ0305 was built by homology modeling. We compared the stability of MJ0305 with mesophilic Ecoli at 300K, 330K, and 360K by computer simulation to test the effects of temperature. Our results show that high temperatures significantly affect the number of salt bridges and hydrogen bonds. High temperatures decreased the average number of hydrogen bonds for Ecoli and MJ0305. Increased salt bridges at 330K make MJ0305 more stable. Network analysis of MJ0305 showed an increase in the number of hubs at high temperatures. In contrast, the number of hubs of Ecoli was decreased at high temperatures. Calculated network entropy is proportional to the number of hubs. Increased network entropy of MJ0305 at 330K implies increased robustness.

  17. A Systems Dynamic Model for Drug Abuse and Drug-Related Crime in the Western Cape Province of South Africa

    OpenAIRE

    Nyabadza, Farai; Coetzee, Lezanie

    2017-01-01

    The complex problem of drug abuse and drug-related crimes in communities in the Western Cape province cannot be studied in isolation but through the system they are embedded in. In this paper, a theoretical model to evaluate the syndemic of substance abuse and drug-related crimes within the Western Cape province of South Africa is constructed and explored. The dynamics of drug abuse and drug-related crimes within the Western Cape are simulated using STELLA software. The simulation results are...

  18. Nanohydroxyapatite Silicate-Based Cement Improves the Primary Stability of Dental Implants: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Hooman Khorshidi

    2017-01-01

    Full Text Available Objectives. Insufficient cortical bone volume when placing implants can lead to lack of primary stability. The use of cement as a bone fill material in bone defects around dental implant could result in better clinical outcome. HA has shown excellent biological properties in implant dentistry. The purpose of this study was to evaluate the effect of nanohydroxyapatite powder (Nano-HA in combination with accelerated Portland cement (APC on implant primary stability in surgically created circumferential bone defects in a bovine rib in vitro model. Materials and Methods. Sixteen bovine rib bones and thirty-six implants of same type and size (4 mm × 10 mm were used. Implants were divided into six groups: no circumferential bone defect, defect and no grafting, bone chips grafting, Nano-HA grafting, APC grafting, and Nano-HA mixed to APC grafting (Nano-HA-APC. Circumferential defects around the implants were prepared. The implant stability quotient (ISQ values were measured before and after the grafting. Results. APC exhibited the highest ISQ values. A significant increase of ISQ values following the grafting of Nano-HA-APC (18.08±5.82 and APC alone (9.50±4.12 was achieved. Increase of ISQ values after 72 hours was 24.16±5.01 and 17.58±4.89, respectively. Nano-HA grafting alone exhibited the least rise in ISQ values. Conclusions. Nanohydroxyapatite silicate-based cement could improve the primary stability of dental implants in circumferential bone defect around implants.

  19. Updated secondary implant stability data of two dental implant systems. A retrospective cohort study.

    Science.gov (United States)

    Grognard, Nicolas; Verleye, Gino; Mavreas, Dimitrios; Vande-Vannet, Bart

    2017-09-01

    At present, updated secondary implant stability data generated by actual versions of resonance frequency analysis (RFA) and mobility measurement (MM) electronic devices of 2 different implant systems with actual manufactured surfaces seem to lack and/or are incomplete. Secondary implant stability data based on both RFA and MM measurements were collected and analyzed from 44 formerly treated patients (24 f, 20 m) that received either Ankylos Cellplus (Ø3.5mm) (A) (n=36) or Straumann regular neck SLA tissue level (Ø4.1mm) (S) (n=37) implants in posterior positions of both jawbones (total number= 72). These results were interpretated in view of formerly published data. Estimated RFA outcomes (mean±SD) for A implants were of 81.23 (±0.65) (LP) - 76.15 (±1.57) (UP) isq; for S implants 76.15 (±1.48) (LP) - 73.88 (±2.34) (UP) isq. Estimated MM outcomes for A implants were (-4.0) (±0.23) (LP) - (-3.2) (±0.33) (UP) ptv; for S implants (-5.15) (±0.39) (LP) - (-4.4) (±0.84) (UP) ptv. According to GEE statistical modelling, implant type and - position seems to influence the outcome variables ( p 0.05). Secondary implant stability values, recorded with current RFA and MM devices, of A Cellplus implants are provided for the first time. A difference of 14.7-9.7 isq values was noted for CellPlus versus TPS S implants recorded with a cabled RFA device. This study supports the assumption that RFA outcomes generated with first generation RFA devices are different from those obtained with current RFA devices, meaning that its use in reviews need caution and correction. Key words: Secondary implant stability, resonance frequency analysis, Periotest, Osstell Mentor, Straumann, Ankylos, CellPlus, SLA.

  20. Stability studies of lincomycin hydrochloride in aqueous solution and intravenous infusion fluids.

    Science.gov (United States)

    Czarniak, Petra; Boddy, Michael; Sunderland, Bruce; Hughes, Jeff D

    2016-01-01

    The purpose of this study was to evaluate the chemical stability of Lincocin(®) (lincomycin hydrochloride) in commonly used intravenous fluids at room temperature (25°C), at accelerated-degradation temperatures and in selected buffer solutions. The stability of Lincocin(®) injection (containing lincomycin 600 mg/2 mL as the hydrochloride) stored at 25°C±0.1°C in sodium lactate (Hartmann's), 0.9% sodium chloride, 5% glucose, and 10% glucose solutions was investigated over 31 days. Forced degradation of Lincocin(®) in hydrochloric acid, sodium hydroxide, and hydrogen peroxide was performed at 60°C. The effect of pH on the degradation rate of lincomycin hydrochloride stored at 80°C was determined. Lincomycin hydrochloride w as found to maintain its shelf life at 25°C in sodium lactate (Hartmann's) solution, 0.9% sodium chloride solution, 5% glucose solution, and 10% glucose solution, with less than 5% lincomycin degradation occurring in all intravenous solutions over a 31-day period. Lincomycin hydrochloride showed less rapid degradation at 60°C in acid than in basic solution, but degraded rapidly in hydrogen peroxide. At all pH values tested, lincomycin followed first-order kinetics. It had the greatest stability near pH 4 when stored at 80°C (calculated shelf life of 4.59 days), and was least stable at pH 2 (calculated shelf life of 0.38 days). Lincocin(®) injection was chemically found to have a shelf life of at least 31 days at 25°C when added to sodium lactate (Hartmann's) solution, 0.9% sodium chloride solution, 5% glucose solution, and 10% glucose solution. Solutions prepared at approximately pH 4 are likely to have optimum stability.

  1. Study of the local stability of a feedback control having rectifiers with a controlled grid

    International Nuclear Information System (INIS)

    Katz, A.

    1962-01-01

    The equivalence of a rectifier with a controlled grid and a sampled device is established. Then, the sampled servomechanism theory is applied to the study of the response and of the local stability of a feedback control having a rectifiers system charged by an inductance-resistance assembly, in the case of the permanent conduction. The case of a feedback control of the first order and then of the second order are studied. The expressions of the test and sampled responses with a sinusoidal input is given. (O.M.) [fr

  2. Study of thermal stability and degradation of fire resistant candidate polymers for aircraft interiors

    Science.gov (United States)

    Hsu, M. T. S.

    1976-01-01

    The thermochemistry of bismaleimide resins and phenolphthalein polycarbonate was studied. Both materials are fire-resistant polymers and may be suitable for aircraft interiors. The chemical composition of the polymers has been determined by nuclear magnetic resonance and infrared spectroscopy and by elemental analysis. Thermal properties of these polymers have been characterized by thermogravimetric analyses. Qualitative evaluation of the volatile products formed in pyrolysis under oxidative and non-oxidative conditions has been made using infrared spectrometry. The residues after pyrolysis were analyzed by elemental analysis. The thermal stability of composite panel and thermoplastic materials for aircraft interiors was studied by thermogravimetric analyses.

  3. Study of the stability of the gallium isotopes beyond the N = 50 neutron shell closure

    CERN Multimedia

    We propose to study the stability of the nuclear structure beyond N = 50 and Z = 28 with beams of neutron-rich gallium isotopes at the CRIS experiment at ISOLDE. The study of their hyperne structure and isotope shift will provide spins, magnetic dipole moments, electric quadrupole moments and changes in the mean-square charge radii. The $\\beta$-decay of $^{80}$Ga will be unambiguously measured using the technique of Laser Assisted Nuclear Decay Spectroscopy (LANDS). The half-lives of the very neutron-rich isotopes with N > 54 will be measured for their impact on the astrophysical ${r}$-process.

  4. Study of the influence of imperfections on the dynamic stability of tanks

    International Nuclear Information System (INIS)

    Uras, R.A.; Liu, Wing Kam; Chen, Yi-Jung

    1990-01-01

    The influence of geometrical imperfections on the dynamic stability of liquid-filled shells under horizontal ground excitation is studied. Some basic concepts in the large deformation and large deformation thin shell theory are recalled. The work done by inertial and internal forces are given in the Gaussian surface coordinate system. A general imperfection pattern in the circumferential direction is introduced. The emphasis is particularly dedicated to the analysis of the geometrical stiffness term. Different patterns are studied to explain the occurrence of additional instability regions. 6 refs., 1 fig., 3 tabs

  5. Wave Climate and Littoral Sediment Transport Potential, Cape Fear River Entrance and Smith Island to Ocean Isle Beach, North Carolina

    National Research Council Canada - National Science Library

    Thompson, Edward

    1999-01-01

    Numerical model studies were conducted to assist the U.S. Army Engineer District, Wilmington, in evaluating potential plans for modifying the Cape Fear River entrance channel and in preparing General Reevaluation Reports...

  6. Study of stability of time-domain features for electromyographic pattern recognition

    Directory of Open Access Journals (Sweden)

    Huang He

    2010-05-01

    Full Text Available Abstract Background Significant progress has been made towards the clinical application of human-machine interfaces (HMIs based on electromyographic (EMG pattern recognition for various rehabilitation purposes. Making this technology practical and available to patients with motor deficits requires overcoming real-world challenges, such as physical and physiological changes, that result in variations in EMG signals and systems that are unreliable for long-term use. In this study, we aimed to address these challenges by (1 investigating the stability of time-domain EMG features during changes in the EMG signals and (2 identifying the feature sets that would provide the most robust EMG pattern recognition. Methods Variations in EMG signals were introduced during physical experiments. We identified three disturbances that commonly affect EMG signals: EMG electrode location shift, variation in muscle contraction effort, and muscle fatigue. The impact of these disturbances on individual features and combined feature sets was quantified by changes in classification performance. The robustness of feature sets was evaluated by a stability index developed in this study. Results Muscle fatigue had the smallest effect on the studied EMG features, while electrode location shift and varying effort level significantly reduced the classification accuracy for most of the features. Under these disturbances, the most stable EMG feature set with combination of four features produced at least 16.0% higher classification accuracy than the least stable set. EMG autoregression coefficients and cepstrum coefficients showed the most robust classification performance of all studied time-domain features. Conclusions Selecting appropriate EMG feature combinations can overcome the impact of the studied disturbances on EMG pattern classification to a certain extent; however, this simple solution is still inadequate. Stabilizing electrode contact locations and developing

  7. Ticks and haemoparasites of dogs from Praia, Cape Verde.

    Science.gov (United States)

    Götsch, S; Leschnik, M; Duscher, G; Burgstaller, J P; Wille-Piazzai, W; Joachim, A

    2009-12-03

    In February 2008 an epidemiological field study on arthropod-borne infections in dogs was carried out in Praia, the capital city of Cape Verde. For this purpose 130 dogs were included in the study. Of these, 94.6% were infested with ticks. Altogether, 1293 ticks of the genus Rhipicephalus (in all evaluated cases R. sanguineus) were collected. Examination for haemotropic parasites was performed via polymerase chain reaction (PCR). Lymph node fine-needle aspirates were screened by PCR for Leishmania infantum infections in 20 dogs with enlarged lymph nodes. Our investigation revealed two species of protozoa (Babesia canis vogeli and Hepatozoon canis) and two species of rickettsiae (Anaplasma platys and Ehrlichia canis). In 101 dogs (77.7%) DNA of one or more pathogens was detected. The PCR examination for H. canis was positive in 83 dogs (63.8%), for E. canis in 34 dogs (26.2%), for A. platys in 10 dogs (7.7%) and for B. canis in five dogs (3.8%), whereas neither B. gibsoni nor L. infantum DNA could be detected. Of the infected dogs, 71.3% had a monoinfection, 27.7% had infections with two pathogens and 1.0% with three pathogens. B. canis, H. canis, E. canis, A. platys and their vector tick R. sanguineus are endemic to Cape Verde and can be present in dogs in high prevalences. These results outline the risk of importing tropical canine diseases when Capeverdian stray dogs are taken to Europe.

  8. Great deal achieved at Cape's nuclear island

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Since the civil engineering contract commenced a great deal has been achieved at Escom's Koeberg nuclear power station north of Cape Town. About 50 percent of the civil work has now been done and the entire project remains on schedule for a January 1982 start-up on nuclear reactor unit number one and a January 1983 start-up on unit two. Final handover is scheduled for January 1984. Completion of the civil works is scheduled for December 1981. The construction of the Koeberg nuclear power station is discussed, as well as the contractors for the civil engineering work

  9. Some observations on two early Cape florilegia

    Directory of Open Access Journals (Sweden)

    E. G. H. Oliver

    1980-11-01

    Full Text Available A number of early Cape florilegia and codices exist in libraries in Europe and South Africa. Four of these florilegia are closely related and are housed in the Brenthurst Library, Johannesburg, the Botanical Research Institute, Pretoria, the Bodleian Library, Oxford and the Rijksherbarium, Leiden. The first two are compared and discussed in detail in this article. Arising from this comparison, a new interpretation of the interrelationship and origins of the four florilegia is proposed. The key volume is the florilegium in the Botanical Research Institute, Pretoria.

  10. Environmental Restoration of Diesel-Range Organics from Project Chariot, Cape Thompson, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Kautsky, Mark [U.S. Department of Energy, Office of Legacy Management; Hutton, Rick [Navarro Research & Engineering; Miller, Judy [Navarro Research & Engineering

    2016-03-06

    The Chariot site is located in the Ogotoruk Valley in the Cape Thompson region of northwest Alaska. Project Chariot was part of the Plowshare Program, created in 1957 by the US Atomic Energy Commission (AEC), a predecessor agency of the US Department of Energy (DOE), to study peaceful uses for atomic energy. Project Chariot began in 1958 when a scientific field team chose Cape Thompson as a potential site to excavate a harbor using a series of nuclear explosions. AEC, with assistance from other agencies, conducted more than 40 pretest bioenvironmental studies of the Cape Thompson area between 1959 and 1962; however, the Plowshare Program work at the Project Chariot site (Figure 1) was cancelled because of strong public opposition [1]. No nuclear explosions were ever conducted at the site.

  11. Analytical Approaches for Identification and Representation of Critical Protection Systems in Transient Stability Studies

    Science.gov (United States)

    Hedman, Mojdeh Khorsand

    After a major disturbance, the power system response is highly dependent on protection schemes and system dynamics. Improving power systems situational awareness requires proper and simultaneous modeling of both protection schemes and dynamic characteristics in power systems analysis tools. Historical information and ex-post analysis of blackouts reaffirm the critical role of protective devices in cascading events, thereby confirming the necessity to represent protective functions in transient stability studies. This dissertation is aimed at studying the importance of representing protective relays in power system dynamic studies. Although modeling all of the protective relays within transient stability studies may result in a better estimation of system behavior, representing, updating, and maintaining the protection system data becomes an insurmountable task. Inappropriate or outdated representation of the relays may result in incorrect assessment of the system behavior. This dissertation presents a systematic method to determine essential relays to be modeled in transient stability studies. The desired approach should identify protective relays that are critical for various operating conditions and contingencies. The results of the transient stability studies confirm that modeling only the identified critical protective relays is sufficient to capture system behavior for various operating conditions and precludes the need to model all of the protective relays. Moreover, this dissertation proposes a method that can be implemented to determine the appropriate location of out-of-step blocking relays. During unstable power swings, a generator or group of generators may accelerate or decelerate leading to voltage depression at the electrical center along with generator tripping. This voltage depression may cause protective relay mis-operation and unintentional separation of the system. In order to avoid unintentional islanding, the potentially mis-operating relays

  12. Perceptions of the role of the clinical nurse practitioner in the Cape ...

    African Journals Online (AJOL)

    Background: The purpose of this study was to evaluate the role of the clinical nurse practitioner (CNP) in a doctordriven primary health care setting. A descriptive study was undertaken, using both a quantitative and a qualitative methodology. The study was undertaken in community health centres (CHC) in the Cape ...

  13. Stability studies of lincomycin hydrochloride in aqueous solution and intravenous infusion fluids

    Directory of Open Access Journals (Sweden)

    Czarniak P

    2016-03-01

    Full Text Available Petra Czarniak, Michael Boddy, Bruce Sunderland, Jeff D Hughes School of Pharmacy, Curtin University, Perth, WA, Australia Purpose: The purpose of this study was to evaluate the chemical stability of Lincocin® (lincomycin hydrochloride in commonly used intravenous fluids at room temperature (25°C, at accelerated-degradation temperatures and in selected buffer solutions.Materials and methods: The stability of Lincocin® injection (containing lincomycin 600 mg/2 mL as the hydrochloride stored at 25°C±0.1°C in sodium lactate (Hartmann’s, 0.9% sodium chloride, 5% glucose, and 10% glucose solutions was investigated over 31 days. Forced degradation of Lincocin® in hydrochloric acid, sodium hydroxide, and hydrogen peroxide was performed at 60°C. The effect of pH on the degradation rate of lincomycin hydrochloride stored at 80°C was determined.Results: Lincomycin hydrochloride was found to maintain its shelf life at 25°C in sodium lactate (Hartmann’s solution, 0.9% sodium chloride solution, 5% glucose solution, and 10% glucose solution, with less than 5% lincomycin degradation occurring in all intravenous solutions over a 31-day period. Lincomycin hydrochloride showed less rapid degradation at 60°C in acid than in basic solution, but degraded rapidly in hydrogen peroxide. At all pH values tested, lincomycin followed first-order kinetics. It had the greatest stability near pH 4 when stored at 80°C (calculated shelf life of 4.59 days, and was least stable at pH 2 (calculated shelf life of 0.38 days.Conclusion: Lincocin® injection was chemically found to have a shelf life of at least 31 days at 25°C when added to sodium lactate (Hartmann’s solution, 0.9% sodium chloride solution, 5% glucose solution, and 10% glucose solution. Solutions prepared at approximately pH 4 are likely to have optimum stability. Keywords: lincomycin, stability, pH, intravenous fluids, IV additives

  14. Synthesis and Stability Studies of α,α‐Difluoro Ester Phospholipids

    DEFF Research Database (Denmark)

    Pedersen, Palle Jacob; Andresen, Thomas Lars; Clausen, Mads Hartvig

    2012-01-01

    The synthesis of two new α,α‐difluoro ester phospholipid conjugates is described and the stability of their liposomal formulations in three different aqueous buffers (pH 4.5, 7.5 and 8.5) has been investigated. The studies confirmed that α,α‐difluoro esters are much more prone to hydrolysis when...... positioned close to the hydrophilic head group of phospholipids than when the functionality is placed in the lipophilic part of the bilayer in liposomes. This observation lends further support to the concept of protecting hydrolysable functionalities by formulation as part of the membrane of liposomes....

  15. Numerical study of solitary wave stability in cubic nonlinear Dirac equations in 1D

    Science.gov (United States)

    Lakoba, T. I.

    2018-02-01

    Recently there has occurred a controversy between the semi-analytical prediction of linear stability of the soliton of the massive Gross-Neveu model and direct numerical observations of its instability for small values of the frequency. We revisit the problem of numerical computation of this soliton, find a mechanism behind the numerical instability observed in earlier studies, and propose methods to stably compute the soliton over long times. Thus, we confirm the semi-analytical prediction of the soliton's being linearly stable.

  16. Study of Thermal Stress Influence on Dimensional Stability of Silicone Molds

    OpenAIRE

    Bajčičák Martin; Šuba Roland

    2014-01-01

    The paper is focused on the study of temperature influence on dimensional stability of silicone molds used for spin casting of the low melting points alloys. The silicone material denoted as TEKSIL Silicone-GP-S was used to produce samples during experiments. The samples were heated to temperatures in the range from 100 up to 250oC for 30 up to 120 min. Dimensional changes of the samples in the radial and axial directions aa well as their change of weight were evaluated. The results of experi...

  17. A Study of Wind Farm Stabilization Using DFIG or STATCOM Considering Grid Requirements

    Directory of Open Access Journals (Sweden)

    K. E Okedu

    2010-01-01

    Full Text Available Recently, the grid codes require taking into account the reactive power of the wind farm in order to contribute to the networkstability, thus operating the wind farm as active compensator devices. This paper presents a comparative study of stabilizinga wind farm using (Doubly Fed Induction Generators DFIGs or using a (Static Synchronous Compensator STATCOM duringwind speed change and grid fault. Simulation results show that the wind farm could be effectively stabilized with bothsystems, but at a reduced cost with the DFIGs system because it can provide reactive power through its frequency converterswithout an external reactive power compensation unit like the STATCOM system significant.

  18. Stability of avocado oil during heating: comparative study to olive oil

    OpenAIRE

    Berasategi, I. (Izaskun); Barriuso, B. (Blanca); Ansorena, D. (Diana); Astiasarán, I. (Iciar)

    2012-01-01

    The stability of the saponifiable and unsaponifiable fractions of avocado oil, under a drastic heating treatment, was studied and compared to that of olive oil. Avocado and olive oil were characterised and compared at time 0 h and after different times of heating process (180 °C). PUFA/SFA (0.61 at t = 0) and ω-6/ω-3 (14.05 at t = 0) were higher in avocado oil than in olive oil during the whole experiment. Avocado oil was richer than olive oil in total phytosterols at time 0 h (339.64; 228.27...

  19. STUDYING THE INFLUENCE OF THE PYRENE INTERCALATOR TINA ON THE STABILITY OF DNA i-MOTIFS

    DEFF Research Database (Denmark)

    El-Sayed, Ahmed A.; Pedersen, Erik Bjerregaard; Khaireldin, Nahid A.

    2012-01-01

    Certain cytosine-rich (C-rich) DNA sequences can fold into secondary structures as four-stranded i-motifs with hemiprotonated base pairs. Here we synthesized C-rich TINA-intercalating oligonucleotides by inserting a nonnucleotide pyrene moiety between two C-rich regions. The stability of their i......-motif structures was studied by using UV melting temperature measurements and circular dichroism spectra at different pH values under noncrowding and crowding conditions (20% poly(ethylene glycol)). When TINA ((R)-3-((4-(1-pyrenylethynyl)benzyl)oxy) propane-1,2-diol) is inserted, the oligonucleotides could form...

  20. Study of stability of terrylitine chemically bound with polymer to γ-irradiation

    International Nuclear Information System (INIS)

    Yudanova, T.N.; Skokova, I.F.; Dovbij, E.V.; Kalashnik, A.T.

    1987-01-01

    Using ESR method the mechanism of the increase in stability to γ-irradiation of proteolytic enzyme terrylitine immobilized on cellulose derivatives, has been studied. It is shown that in the process of γ-sterilization by the doses of 25 kGy at the dose rate 1.1 Gy/s migration of terrylitine free valency to macromolecule of polymer-carrier takes place, and in certain cases recombination of enzyme and polymer macroradicals occurs. Due to the fact proteolytic activity of immobilized terrylitine during γ-sterilization does not decrease practically