Persistent PlatformsThe DDG 51 Case
2015-09-30
Retrieved from http://insidedefense.com Biernacki, P., & Waldorf, D. (1981). Snowball sampling : Problems and techniques of chain referral sampling ...indicators of successful shipbuilding practices (Government Accountability Office [GAO], 2009). This paper uses the “ snowball ” technique of data gathering
Siddiqui, Niyamat A.; Rabidas, Vidya N.; Sinha, Sanjay K.; Verma, Rakesh B.; Pandey, Krishna; Singh, Vijay P.; Ranjan, Alok; Topno, Roshan K.; Lal, Chandra S.; Kumar, Vijay; Sahoo, Ganesh C.; Sridhar, Srikantaih; Pandey, Arvind; Das, Pradeep
2016-01-01
Background Visceral Leishmaniasis, commonly known as kala-azar, is widely prevalent in Bihar. The National Kala-azar Control Program has applied house-to-house survey approach several times for estimating Kala-azar incidence in the past. However, this approach includes huge logistics and operational cost, as occurrence of kala-azar is clustered in nature. The present study aims to compare efficiency, cost and feasibility of snowball sampling approach to house-to-house survey approach in capturing kala-azar cases in two endemic districts of Bihar, India. Methodology/Principal findings A community based cross-sectional study was conducted in two highly endemic Primary Health Centre (PHC) areas, each from two endemic districts of Bihar, India. Snowball technique (used to locate potential subjects with help of key informants where subjects are hard to locate) and house-to-house survey technique were applied to detect all the new cases of Kala-azar during a defined reference period of one year i.e. June, 2010 to May, 2011. The study covered a total of 105,035 households with 537,153 populations. Out of total 561 cases and 17 deaths probably due to kala-azar, identified by the study, snowball sampling approach captured only 221 cases and 13 deaths, whereas 489 cases and 17 deaths were detected by house-to-house survey approach. Higher value of McNemar’s χ² statistics (64; p<0.0001) for house-to-house survey approach than snowball sampling and relative difference (>1) indicates that most of the kala-azar cases missed by snowball sampling were captured by house-to-house approach with 13% of omission. Conclusion/Significance Snowball sampling was not found sensitive enough as it captured only about 50% of VL cases. However, it captured about 77% of the deaths probably due to kala-azar and was found more cost-effective than house-to-house approach. Standardization of snowball approach with improved procedure, training and logistics may enhance the sensitivity of snowball sampling and its application in national Kala-azar elimination programme as cost-effective approach for estimation of kala-azar burden. PMID:27681709
Siddiqui, Niyamat A; Rabidas, Vidya N; Sinha, Sanjay K; Verma, Rakesh B; Pandey, Krishna; Singh, Vijay P; Ranjan, Alok; Topno, Roshan K; Lal, Chandra S; Kumar, Vijay; Sahoo, Ganesh C; Sridhar, Srikantaih; Pandey, Arvind; Das, Pradeep
2016-09-01
Visceral Leishmaniasis, commonly known as kala-azar, is widely prevalent in Bihar. The National Kala-azar Control Program has applied house-to-house survey approach several times for estimating Kala-azar incidence in the past. However, this approach includes huge logistics and operational cost, as occurrence of kala-azar is clustered in nature. The present study aims to compare efficiency, cost and feasibility of snowball sampling approach to house-to-house survey approach in capturing kala-azar cases in two endemic districts of Bihar, India. A community based cross-sectional study was conducted in two highly endemic Primary Health Centre (PHC) areas, each from two endemic districts of Bihar, India. Snowball technique (used to locate potential subjects with help of key informants where subjects are hard to locate) and house-to-house survey technique were applied to detect all the new cases of Kala-azar during a defined reference period of one year i.e. June, 2010 to May, 2011. The study covered a total of 105,035 households with 537,153 populations. Out of total 561 cases and 17 deaths probably due to kala-azar, identified by the study, snowball sampling approach captured only 221 cases and 13 deaths, whereas 489 cases and 17 deaths were detected by house-to-house survey approach. Higher value of McNemar's χ² statistics (64; p<0.0001) for house-to-house survey approach than snowball sampling and relative difference (>1) indicates that most of the kala-azar cases missed by snowball sampling were captured by house-to-house approach with 13% of omission. Snowball sampling was not found sensitive enough as it captured only about 50% of VL cases. However, it captured about 77% of the deaths probably due to kala-azar and was found more cost-effective than house-to-house approach. Standardization of snowball approach with improved procedure, training and logistics may enhance the sensitivity of snowball sampling and its application in national Kala-azar elimination programme as cost-effective approach for estimation of kala-azar burden.
Sadler, Georgia Robins; Lee, Hau-Chen; Seung-Hwan Lim, Rod; Fullerton, Judith
2011-01-01
Nurse researchers and educators often engage in outreach to narrowly defined populations. This article offers examples of how variations on the snowball sampling recruitment strategy can be applied in the creation of culturally appropriate, community-based information dissemination efforts related to recruitment to health education programs and research studies. Examples from the primary author’s program of research are provided to demonstrate how adaptations of snowball sampling can be effectively used in the recruitment of members of traditionally underserved or vulnerable populations. The adaptation of snowball sampling techniques, as described in this article, helped the authors to gain access to each of the more vulnerable population groups of interest. The use of culturally sensitive recruitment strategies is both appropriate and effective in enlisting the involvement of members of vulnerable populations. Adaptations of snowball sampling strategies should be considered when recruiting participants for education programs or subjects for research studies when recruitment of a population based sample is not essential. PMID:20727089
Recruitment of hard-to-reach population subgroups via adaptations of the snowball sampling strategy.
Sadler, Georgia Robins; Lee, Hau-Chen; Lim, Rod Seung-Hwan; Fullerton, Judith
2010-09-01
Nurse researchers and educators often engage in outreach to narrowly defined populations. This article offers examples of how variations on the snowball sampling recruitment strategy can be applied in the creation of culturally appropriate, community-based information dissemination efforts related to recruitment to health education programs and research studies. Examples from the primary author's program of research are provided to demonstrate how adaptations of snowball sampling can be used effectively in the recruitment of members of traditionally underserved or vulnerable populations. The adaptation of snowball sampling techniques, as described in this article, helped the authors to gain access to each of the more-vulnerable population groups of interest. The use of culturally sensitive recruitment strategies is both appropriate and effective in enlisting the involvement of members of vulnerable populations. Adaptations of snowball sampling strategies should be considered when recruiting participants for education programs or for research studies when the recruitment of a population-based sample is not essential.
Kaplan, C D; Korf, D; Sterk, C
1987-09-01
Snowball sampling is a method that has been used in the social sciences to study sensitive topics, rare traits, personal networks, and social relationships. The method involves the selection of samples utilizing "insider" knowledge and referral chains among subjects who possess common traits that are of research interest. It is especially useful in generating samples for which clinical sampling frames may be difficult to obtain or are biased in some way. In this paper, snowball samples of heroin users in two Dutch cities have been analyzed for the purpose of providing descriptions and limited inferences about the temporal and social contexts of their lifestyles. Two distinct heroin-using populations have been discovered who are distinguished by their life cycle stage. Significant contextual explanations have been found involving the passage from adolescent peer group to criminal occupation, the functioning of network "knots" and "outcroppings," and the frequency of social contact. It is suggested that the snowball sampling method may have utility in studying the temporal and social contexts of other populations of clinical interest.
Davis, Stacy N; Govindaraju, Swapamthi; Jackson, Brittany; Williams, Kimberly R; Christy, Shannon M; Vadaparampil, Susan T; Quinn, Gwendolyn P; Shibata, David; Roetzheim, Richard; Meade, Cathy D; Gwede, Clement K
Recruiting ethnically diverse Black participants to an innovative, community-based research study to reduce colorectal cancer screening disparities requires multipronged recruitment techniques. This article describes active, passive, and snowball recruitment techniques, and challenges and lessons learned in recruiting a diverse sample of Black participants. For each of the three recruitment techniques, data were collected on strategies, enrollment efficiency (participants enrolled/participants evaluated), and reasons for ineligibility. Five hundred sixty individuals were evaluated, and 330 individuals were enrolled. Active recruitment yielded the highest number of enrolled participants, followed by passive and snowball. Snowball recruitment was the most efficient technique, with enrollment efficiency of 72.4%, followed by passive (58.1%) and active (55.7%) techniques. There were significant differences in gender, education, country of origin, health insurance, and having a regular physician by recruitment technique (p < .05). Multipronged recruitment techniques should be employed to increase reach, diversity, and study participation rates among Blacks. Although each recruitment technique had a variable enrollment efficiency, the use of multipronged recruitment techniques can lead to successful enrollment of diverse Blacks into cancer prevention and control interventions.
Stahlman, Shauna; Hargreaves, James; Weir, Sharon; Edwards, Jessie; Rice, Brian; Kochelani, Duncan; Mavimbela, Mpumelelo; Baral, Stefan
2017-01-01
Background In using regularly collected or existing surveillance data to characterize engagement in human immunodeficiency virus (HIV) services among marginalized populations, differences in sampling methods may produce different pictures of the target population and may therefore result in different priorities for response. Objective The objective of this study was to use existing data to evaluate the sample distribution of eight studies of female sex workers (FSW) and men who have sex with men (MSM), who were recruited using different sampling approaches in two locations within Sub-Saharan Africa: Manzini, Swaziland and Yaoundé, Cameroon. Methods MSM and FSW participants were recruited using either respondent-driven sampling (RDS) or venue-based snowball sampling. Recruitment took place between 2011 and 2016. Participants at each study site were administered a face-to-face survey to assess sociodemographics, along with the prevalence of self-reported HIV status, frequency of HIV testing, stigma, and other HIV-related characteristics. Crude and RDS-adjusted prevalence estimates were calculated. Crude prevalence estimates from the venue-based snowball samples were compared with the overlap of the RDS-adjusted prevalence estimates, between both FSW and MSM in Cameroon and Swaziland. Results RDS samples tended to be younger (MSM aged 18-21 years in Swaziland: 47.6% [139/310] in RDS vs 24.3% [42/173] in Snowball, in Cameroon: 47.9% [99/306] in RDS vs 20.1% [52/259] in Snowball; FSW aged 18-21 years in Swaziland 42.5% [82/325] in RDS vs 8.0% [20/249] in Snowball; in Cameroon 15.6% [75/576] in RDS vs 8.1% [25/306] in Snowball). They were less educated (MSM: primary school completed or less in Swaziland 42.6% [109/310] in RDS vs 4.0% [7/173] in Snowball, in Cameroon 46.2% [138/306] in RDS vs 14.3% [37/259] in Snowball; FSW: primary school completed or less in Swaziland 86.6% [281/325] in RDS vs 23.9% [59/247] in Snowball, in Cameroon 87.4% [520/576] in RDS vs 77.5% [238/307] in Snowball) than the snowball samples. In addition, RDS samples indicated lower exposure to HIV prevention information, less knowledge about HIV prevention, limited access to HIV prevention tools such as condoms, and less-reported frequency of sexually transmitted infections (STI) and HIV testing as compared with the venue-based samples. Findings pertaining to the level of disclosure of sexual practices and sexual practice–related stigma were mixed. Conclusions Samples generated by RDS and venue-based snowball sampling produced significantly different prevalence estimates of several important characteristics. These findings are tempered by limitations to the application of both approaches in practice. Ultimately, these findings provide further context for understanding existing surveillance data and how differences in methods of sampling can influence both the type of individuals captured and whether or not these individuals are representative of the larger target population. These data highlight the need to consider how program coverage estimates of marginalized populations are determined when characterizing the level of unmet need. PMID:29054832
ERIC Educational Resources Information Center
Alloh, Folashade T.; Tait, Desiree; Taylor, Clare
2018-01-01
This study explored the factors that contribute to the health experience of Nigerian students in the United Kingdom. Challenges faced by international students include dietary issues, isolation, stress, depression, and others. Nine semi-structured interviews were conducted combination of purposive sampling and snowball sampling techniques were…
Rao, Amrita; Stahlman, Shauna; Hargreaves, James; Weir, Sharon; Edwards, Jessie; Rice, Brian; Kochelani, Duncan; Mavimbela, Mpumelelo; Baral, Stefan
2017-10-20
In using regularly collected or existing surveillance data to characterize engagement in human immunodeficiency virus (HIV) services among marginalized populations, differences in sampling methods may produce different pictures of the target population and may therefore result in different priorities for response. The objective of this study was to use existing data to evaluate the sample distribution of eight studies of female sex workers (FSW) and men who have sex with men (MSM), who were recruited using different sampling approaches in two locations within Sub-Saharan Africa: Manzini, Swaziland and Yaoundé, Cameroon. MSM and FSW participants were recruited using either respondent-driven sampling (RDS) or venue-based snowball sampling. Recruitment took place between 2011 and 2016. Participants at each study site were administered a face-to-face survey to assess sociodemographics, along with the prevalence of self-reported HIV status, frequency of HIV testing, stigma, and other HIV-related characteristics. Crude and RDS-adjusted prevalence estimates were calculated. Crude prevalence estimates from the venue-based snowball samples were compared with the overlap of the RDS-adjusted prevalence estimates, between both FSW and MSM in Cameroon and Swaziland. RDS samples tended to be younger (MSM aged 18-21 years in Swaziland: 47.6% [139/310] in RDS vs 24.3% [42/173] in Snowball, in Cameroon: 47.9% [99/306] in RDS vs 20.1% [52/259] in Snowball; FSW aged 18-21 years in Swaziland 42.5% [82/325] in RDS vs 8.0% [20/249] in Snowball; in Cameroon 15.6% [75/576] in RDS vs 8.1% [25/306] in Snowball). They were less educated (MSM: primary school completed or less in Swaziland 42.6% [109/310] in RDS vs 4.0% [7/173] in Snowball, in Cameroon 46.2% [138/306] in RDS vs 14.3% [37/259] in Snowball; FSW: primary school completed or less in Swaziland 86.6% [281/325] in RDS vs 23.9% [59/247] in Snowball, in Cameroon 87.4% [520/576] in RDS vs 77.5% [238/307] in Snowball) than the snowball samples. In addition, RDS samples indicated lower exposure to HIV prevention information, less knowledge about HIV prevention, limited access to HIV prevention tools such as condoms, and less-reported frequency of sexually transmitted infections (STI) and HIV testing as compared with the venue-based samples. Findings pertaining to the level of disclosure of sexual practices and sexual practice-related stigma were mixed. Samples generated by RDS and venue-based snowball sampling produced significantly different prevalence estimates of several important characteristics. These findings are tempered by limitations to the application of both approaches in practice. Ultimately, these findings provide further context for understanding existing surveillance data and how differences in methods of sampling can influence both the type of individuals captured and whether or not these individuals are representative of the larger target population. These data highlight the need to consider how program coverage estimates of marginalized populations are determined when characterizing the level of unmet need. ©Amrita Rao, Shauna Stahlman, James Hargreaves, Sharon Weir, Jessie Edwards, Duncan Kochelani, Duncan Kochelani, Mpumelelo Mavimbela, Stefan Baral. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 20.10.2017.
Types of Bullying in the Senior High Schools in Ghana
ERIC Educational Resources Information Center
Antiri, Kwasi Otopa
2016-01-01
The main objective of the study was to examine the types of bullying that were taking place in the senior high schools in Ghana. A multi-stage sampling procedure, comprising purposive, simple random and snowball sampling technique, was used in the selection of the sample. A total of 354 respondents were drawn six schools in Ashanti, Central and…
Kendall, Carl; Kerr, Ligia R F S; Gondim, Rogerio C; Werneck, Guilherme L; Macena, Raimunda Hermelinda Maia; Pontes, Marta Kerr; Johnston, Lisa G; Sabin, Keith; McFarland, Willi
2008-07-01
Obtaining samples of populations at risk for HIV challenges surveillance, prevention planning, and evaluation. Methods used include snowball sampling, time location sampling (TLS), and respondent-driven sampling (RDS). Few studies have made side-by-side comparisons to assess their relative advantages. We compared snowball, TLS, and RDS surveys of men who have sex with men (MSM) in Forteleza, Brazil, with a focus on the socio-economic status (SES) and risk behaviors of the samples to each other, to known AIDS cases and to the general population. RDS produced a sample with wider inclusion of lower SES than snowball sampling or TLS-a finding of health significance given the majority of AIDS cases reported among MSM in the state were low SES. RDS also achieved the sample size faster and at lower cost. For reasons of inclusion and cost-efficiency, RDS is the sampling methodology of choice for HIV surveillance of MSM in Fortaleza.
Educator-on-Educator Workplace Bullying: A Phenomenological Study
ERIC Educational Resources Information Center
de Wet, N. C.
2011-01-01
Husserlian phenomenology was used as the philosophical underpinning for this study, since its purpose is to describe human experience as it is lived by educators who have experienced workplace bullying. In-depth interviews were conducted with participants identified by means of the snowball sampling technique. Colaizzi's method for descriptive…
NASA Astrophysics Data System (ADS)
Patriarcheas, Kiriakos; Xenos, Michalis
Asynchronous discussion fora all the more become part of the educational process of distance education. The goal of this research is the study of the educational techniques of Brainstorming and Snowballing to their utilisation in the frame of a distance education forum, both as far as participation and creation of learning environment and also educational effectiveness are concerned. This research refers to computer teachers’ training on didactics of programming within the framework of educational micro-worlds. As it is deduced from the data analysis and the study of the messages higher participation and improvement of critical thinking are noted when Brainstorming technique is used, while fairly less time is spent and less off-topic interventions are made when Snowballing technique is used. Meanwhile, Brainstorming is found to be more advantageous than Snowballing concerning the effectiveness both in primary level (trained teachers) and in secondary level of adaptation and knowledge impartment to the students (results of their students).
Transforming Classrooms through Game-Based Learning: A Feasibility Study in a Developing Country
ERIC Educational Resources Information Center
Vate-U-Lan, Poonsri
2015-01-01
This article reports an exploratory study which investigated attitudes towards the practice of game-based learning in teaching STEM (science, technology, engineering and mathematics) within a Thai educational context. This self-administered Internet-based survey yielded 169 responses from a snowball sampling technique. Three fifths of respondents…
Insights into a spatially embedded social network from a large-scale snowball sample
NASA Astrophysics Data System (ADS)
Illenberger, J.; Kowald, M.; Axhausen, K. W.; Nagel, K.
2011-12-01
Much research has been conducted to obtain insights into the basic laws governing human travel behaviour. While the traditional travel survey has been for a long time the main source of travel data, recent approaches to use GPS data, mobile phone data, or the circulation of bank notes as a proxy for human travel behaviour are promising. The present study proposes a further source of such proxy-data: the social network. We collect data using an innovative snowball sampling technique to obtain details on the structure of a leisure-contacts network. We analyse the network with respect to its topology, the individuals' characteristics, and its spatial structure. We further show that a multiplication of the functions describing the spatial distribution of leisure contacts and the frequency of physical contacts results in a trip distribution that is consistent with data from the Swiss travel survey.
Perez, Daniel F; Nie, Jason X; Ardern, Chris I; Radhu, Natasha; Ritvo, Paul
2013-02-01
Community-wide efforts to encourage healthy behaviours must respond to the needs of existing neighbourhoods, especially those where low physical activity (PA) is associated with social, economic, and cultural challenges. This study reports on the effect of direct and snowball sampling strategies and financial incentive levels on the response rates of a built environment and PA survey in a predominately urban, low-SES new-immigrant community. Women residing in the Jane-Finch neighbourhood of Toronto, Ontario were selected to participate by quasi-random sampling, yielding a response rate of 41.5%. The survey completion rate per contact attempt increased 2-fold when incentives were increased from $10 to $20 and a further threefold following the increase from $20 to $30. Snowball sampled respondents were older, less likely to have full-time employment, and had lower educational attainment than directly sampled participants. With appropriate incentives, face-to-face contact, and snowball sampling, survey-based research is feasible within a low-SES, high minority population.
Musical Meaning in the Lives of Those Affected by the Holocaust: Implications for Music Education
ERIC Educational Resources Information Center
Cunningham, Deborah A.
2014-01-01
This qualitative study investigated the role of music in the lives of those affected by the Holocaust. Participants were identified through purposeful and snowball sampling techniques, and a total of five were selected based on their connection to the Holocaust. Participants included those incarcerated in camps and ghettos, those who escaped…
Identifying the Financial Literacy Skills Necessary to Run a Small New Zealand Business
ERIC Educational Resources Information Center
Samkin, Grant; Pitu, Elizabeth; Low, Mary
2014-01-01
The objectives of this paper are to identify the financial skills small business owners believe necessary to be successful in business, and to establish whether there is a role for secondary school accounting in contributing to the learning of these skills. A combination of a social network website and snowball sampling technique was used to…
Comparing two sampling methods to engage hard-to-reach communities in research priority setting.
Valerio, Melissa A; Rodriguez, Natalia; Winkler, Paula; Lopez, Jaime; Dennison, Meagen; Liang, Yuanyuan; Turner, Barbara J
2016-10-28
Effective community-partnered and patient-centered outcomes research needs to address community priorities. However, optimal sampling methods to engage stakeholders from hard-to-reach, vulnerable communities to generate research priorities have not been identified. In two similar rural, largely Hispanic communities, a community advisory board guided recruitment of stakeholders affected by chronic pain using a different method in each community: 1) snowball sampling, a chain- referral method or 2) purposive sampling to recruit diverse stakeholders. In both communities, three groups of stakeholders attended a series of three facilitated meetings to orient, brainstorm, and prioritize ideas (9 meetings/community). Using mixed methods analysis, we compared stakeholder recruitment and retention as well as priorities from both communities' stakeholders on mean ratings of their ideas based on importance and feasibility for implementation in their community. Of 65 eligible stakeholders in one community recruited by snowball sampling, 55 (85 %) consented, 52 (95 %) attended the first meeting, and 36 (65 %) attended all 3 meetings. In the second community, the purposive sampling method was supplemented by convenience sampling to increase recruitment. Of 69 stakeholders recruited by this combined strategy, 62 (90 %) consented, 36 (58 %) attended the first meeting, and 26 (42 %) attended all 3 meetings. Snowball sampling recruited more Hispanics and disabled persons (all P < 0.05). Despite differing recruitment strategies, stakeholders from the two communities identified largely similar ideas for research, focusing on non-pharmacologic interventions for management of chronic pain. Ratings on importance and feasibility for community implementation differed only on the importance of massage services (P = 0.045) which was higher for the purposive/convenience sampling group and for city improvements/transportation services (P = 0.004) which was higher for the snowball sampling group. In each of the two similar hard-to-reach communities, a community advisory board partnered with researchers to implement a different sampling method to recruit stakeholders. The snowball sampling method achieved greater participation with more Hispanics but also more individuals with disabilities than a purposive-convenience sampling method. However, priorities for research on chronic pain from both stakeholder groups were similar. Although utilizing a snowball sampling method appears to be superior, further research is needed on implementation costs and resources.
Wig, Gagan S.; Laumann, Timothy O.; Cohen, Alexander L.; Power, Jonathan D.; Nelson, Steven M.; Glasser, Matthew F.; Miezin, Francis M.; Snyder, Abraham Z.; Schlaggar, Bradley L.; Petersen, Steven E.
2014-01-01
We describe methods for parcellating an individual subject's cortical and subcortical brain structures using resting-state functional correlations (RSFCs). Inspired by approaches from social network analysis, we first describe the application of snowball sampling on RSFC data (RSFC-Snowballing) to identify the centers of cortical areas, subdivisions of subcortical nuclei, and the cerebellum. RSFC-Snowballing parcellation is then compared with parcellation derived from identifying locations where RSFC maps exhibit abrupt transitions (RSFC-Boundary Mapping). RSFC-Snowballing and RSFC-Boundary Mapping largely complement one another, but also provide unique parcellation information; together, the methods identify independent entities with distinct functional correlations across many cortical and subcortical locations in the brain. RSFC parcellation is relatively reliable within a subject scanned across multiple days, and while the locations of many area centers and boundaries appear to exhibit considerable overlap across subjects, there is also cross-subject variability—reinforcing the motivation to parcellate brains at the level of individuals. Finally, examination of a large meta-analysis of task-evoked functional magnetic resonance imaging data reveals that area centers defined by task-evoked activity exhibit correspondence with area centers defined by RSFC-Snowballing. This observation provides important evidence for the ability of RSFC to parcellate broad expanses of an individual's brain into functionally meaningful units. PMID:23476025
Validation of Networks Derived from Snowball Sampling of Municipal Science Education Actors
ERIC Educational Resources Information Center
von der Fehr, Ane; Sølberg, Jan; Bruun, Jesper
2018-01-01
Social network analysis (SNA) has been used in many educational studies in the past decade, but what these studies have in common is that the populations in question in most cases are defined and known to the researchers studying the networks. Snowball sampling is an SNA methodology most often used to study hidden populations, for example, groups…
Wig, Gagan S; Laumann, Timothy O; Cohen, Alexander L; Power, Jonathan D; Nelson, Steven M; Glasser, Matthew F; Miezin, Francis M; Snyder, Abraham Z; Schlaggar, Bradley L; Petersen, Steven E
2014-08-01
We describe methods for parcellating an individual subject's cortical and subcortical brain structures using resting-state functional correlations (RSFCs). Inspired by approaches from social network analysis, we first describe the application of snowball sampling on RSFC data (RSFC-Snowballing) to identify the centers of cortical areas, subdivisions of subcortical nuclei, and the cerebellum. RSFC-Snowballing parcellation is then compared with parcellation derived from identifying locations where RSFC maps exhibit abrupt transitions (RSFC-Boundary Mapping). RSFC-Snowballing and RSFC-Boundary Mapping largely complement one another, but also provide unique parcellation information; together, the methods identify independent entities with distinct functional correlations across many cortical and subcortical locations in the brain. RSFC parcellation is relatively reliable within a subject scanned across multiple days, and while the locations of many area centers and boundaries appear to exhibit considerable overlap across subjects, there is also cross-subject variability-reinforcing the motivation to parcellate brains at the level of individuals. Finally, examination of a large meta-analysis of task-evoked functional magnetic resonance imaging data reveals that area centers defined by task-evoked activity exhibit correspondence with area centers defined by RSFC-Snowballing. This observation provides important evidence for the ability of RSFC to parcellate broad expanses of an individual's brain into functionally meaningful units. © The Author 2013. Published by Oxford University Press.
An improved sampling method of complex network
NASA Astrophysics Data System (ADS)
Gao, Qi; Ding, Xintong; Pan, Feng; Li, Weixing
2014-12-01
Sampling subnet is an important topic of complex network research. Sampling methods influence the structure and characteristics of subnet. Random multiple snowball with Cohen (RMSC) process sampling which combines the advantages of random sampling and snowball sampling is proposed in this paper. It has the ability to explore global information and discover the local structure at the same time. The experiments indicate that this novel sampling method could keep the similarity between sampling subnet and original network on degree distribution, connectivity rate and average shortest path. This method is applicable to the situation where the prior knowledge about degree distribution of original network is not sufficient.
Sampling Methods in Cardiovascular Nursing Research: An Overview.
Kandola, Damanpreet; Banner, Davina; O'Keefe-McCarthy, Sheila; Jassal, Debbie
2014-01-01
Cardiovascular nursing research covers a wide array of topics from health services to psychosocial patient experiences. The selection of specific participant samples is an important part of the research design and process. The sampling strategy employed is of utmost importance to ensure that a representative sample of participants is chosen. There are two main categories of sampling methods: probability and non-probability. Probability sampling is the random selection of elements from the population, where each element of the population has an equal and independent chance of being included in the sample. There are five main types of probability sampling including simple random sampling, systematic sampling, stratified sampling, cluster sampling, and multi-stage sampling. Non-probability sampling methods are those in which elements are chosen through non-random methods for inclusion into the research study and include convenience sampling, purposive sampling, and snowball sampling. Each approach offers distinct advantages and disadvantages and must be considered critically. In this research column, we provide an introduction to these key sampling techniques and draw on examples from the cardiovascular research. Understanding the differences in sampling techniques may aid nurses in effective appraisal of research literature and provide a reference pointfor nurses who engage in cardiovascular research.
RESPONDENT-DRIVEN SAMPLING AS MARKOV CHAIN MONTE CARLO
GOEL, SHARAD; SALGANIK, MATTHEW J.
2013-01-01
Respondent-driven sampling (RDS) is a recently introduced, and now widely used, technique for estimating disease prevalence in hidden populations. RDS data are collected through a snowball mechanism, in which current sample members recruit future sample members. In this paper we present respondent-driven sampling as Markov chain Monte Carlo (MCMC) importance sampling, and we examine the effects of community structure and the recruitment procedure on the variance of RDS estimates. Past work has assumed that the variance of RDS estimates is primarily affected by segregation between healthy and infected individuals. We examine an illustrative model to show that this is not necessarily the case, and that bottlenecks anywhere in the networks can substantially affect estimates. We also show that variance is inflated by a common design feature in which sample members are encouraged to recruit multiple future sample members. The paper concludes with suggestions for implementing and evaluating respondent-driven sampling studies. PMID:19572381
Kahan, David; Al-Tamimi, Alia
2009-10-01
Recruitment of minorities into health studies is a process that has been the subject of recent research effort. The prevalence of hypokinetic disease in the fast growing Middle Eastern-American community is higher than whites and some minority groups and descriptive research is needed to further quantify morbidity status and antecedent behavior. To date, we know of no study that reports recruitment methods of Middle Eastern-American young adults, a demographic group that is transitioning into an at-risk stratum for ethnically associated morbidity. We report and analyze a multi-method approach used in recruiting 240 young adults of this ethnic group into a 1-week study of physical activity utilizing activity logs and pedometers. Participants were primarily recruited through snowball sampling (48.3%), flyers (15.8%), presentations to university campus organizations (15.4%), and graduate research assistants (10.8%). Access was facilitated by assistants who were community insiders; active recruitment was more successful than passive recruitment; and different techniques appealed to different group segments based on gender and religion.
Respondent-driven sampling as Markov chain Monte Carlo.
Goel, Sharad; Salganik, Matthew J
2009-07-30
Respondent-driven sampling (RDS) is a recently introduced, and now widely used, technique for estimating disease prevalence in hidden populations. RDS data are collected through a snowball mechanism, in which current sample members recruit future sample members. In this paper we present RDS as Markov chain Monte Carlo importance sampling, and we examine the effects of community structure and the recruitment procedure on the variance of RDS estimates. Past work has assumed that the variance of RDS estimates is primarily affected by segregation between healthy and infected individuals. We examine an illustrative model to show that this is not necessarily the case, and that bottlenecks anywhere in the networks can substantially affect estimates. We also show that variance is inflated by a common design feature in which the sample members are encouraged to recruit multiple future sample members. The paper concludes with suggestions for implementing and evaluating RDS studies.
NASA Astrophysics Data System (ADS)
Nohda, S.; Uchio, Y.; Kani, T.; Isozaki, Y.; Maruyama, S.
2003-12-01
We have analyzed the limestones occurred in the Kurai area, Altai district, Russia to define Pb-Pb isochron age and examine their variation of Sr isotopic compositions through time. The limestones are inferred to have deposited at the boundary of the Vendian-Cambrian from stratigraphic analyses. In this study, We have newly collected samples for the purpose of the present Pb isotopic study on the basis of the reinvestigated stratigraphic map. Samples are also available from various horizons to examine isotopic variation of Sr through time. We made a minor modification on the method of Pb extraction process from the samples to maintain a stable and higher yield, which made it possible to obtain reliable Pb isotopic data. At present, we have obtained an isochron age of 598 + - 25 Ma (MSWD=1.06) for 9 samples. The present age is evidently older than the boundary of the Vendian-Cambrian, and seems to be correlated with the snowball Earth event. Sr isotopes show substantial variation from 0.7059 to 0.7077 which is interpreted in terms of environmental change during the snowball Earth event. Besides the Pb isotopic age, homogenous 208Pb/204Pb ratios of the samples are suggestive that Th/Pb ratio had been uniform within the seawater or through the formation process of the limestone.
Ruiz-Veguilla, Miguel; Barrigón, María Luisa; Hernández, Laureano; Rubio, José Luis; Gurpegui, Manuel; Sarramea, Fernando; Cervilla, Jorge; Gutiérrez, Blanca; James, Anthony; Ferrin, Maite
2013-08-01
This study aimed to explore the associations between daily cannabis use and the specific profiles of subclinical symptoms in a non-clinical population obtained through snowball sampling, taking into account alcohol use, other drug use, social exclusion and age at onset of cannabis use. We included 85 daily cannabis users and 100 non-daily cannabis users. Both the case and the control populations were identified by snowball sampling. Daily cannabis use was associated with more alcohol intake and other drug use, as well as with early onset in the use of cannabis. Daily cannabis use appeared to exert a dose-response effect on first-rank symptoms, mania symptoms and auditory hallucinations, even after adjusting for sex, age, other drug use, social exclusion and age at onset of cannabis use. The paranoid dimension was only associated with the heaviest consumption of cannabis. Initial age of cannabis use modified the effects of daily cannabis use on the first-rank and voices experiences. Daily cannabis use was associated with significantly more first-rank and voices experiences among those subjects who started to use cannabis before 17 years of age. Our study supports the association of psychotic experiences with cannabis use even among non-psychotic subjects. Copyright © 2013 Elsevier Ltd. All rights reserved.
Using snowball sampling method with nurses to understand medication administration errors.
Sheu, Shuh-Jen; Wei, Ien-Lan; Chen, Ching-Huey; Yu, Shu; Tang, Fu-In
2009-02-01
We aimed to encourage nurses to release information about drug administration errors to increase understanding of error-related circumstances and to identify high-alert situations. Drug administration errors represent the majority of medication errors, but errors are underreported. Effective ways are lacking to encourage nurses to actively report errors. Snowball sampling was conducted to recruit participants. A semi-structured questionnaire was used to record types of error, hospital and nurse backgrounds, patient consequences, error discovery mechanisms and reporting rates. Eighty-five nurses participated, reporting 328 administration errors (259 actual, 69 near misses). Most errors occurred in medical surgical wards of teaching hospitals, during day shifts, committed by nurses working fewer than two years. Leading errors were wrong drugs and doses, each accounting for about one-third of total errors. Among 259 actual errors, 83.8% resulted in no adverse effects; among remaining 16.2%, 6.6% had mild consequences and 9.6% had serious consequences (severe reaction, coma, death). Actual errors and near misses were discovered mainly through double-check procedures by colleagues and nurses responsible for errors; reporting rates were 62.5% (162/259) vs. 50.7% (35/69) and only 3.5% (9/259) vs. 0% (0/69) were disclosed to patients and families. High-alert situations included administration of 15% KCl, insulin and Pitocin; using intravenous pumps; and implementation of cardiopulmonary resuscitation (CPR). Snowball sampling proved to be an effective way to encourage nurses to release details concerning medication errors. Using empirical data, we identified high-alert situations. Strategies for reducing drug administration errors by nurses are suggested. Survey results suggest that nurses should double check medication administration in known high-alert situations. Nursing management can use snowball sampling to gather error details from nurses in a non-reprimanding atmosphere, helping to establish standard operational procedures for known high-alert situations.
How to find future ecstasy-users: targeted and snowball sampling in an ethically sensitive context.
Vervaeke, Hylke K E; Korf, Dirk J; Benschop, Annemieke; van den Brink, Wim
2007-08-01
This article documents the design and the sampling procedures of a prospective longitudinal multidisciplinary study on the neurotoxicity of ecstasy (MDMA): the Netherlands XTC Toxicity Study (NeXT). Targeted and snowball sampling was used to recruit 188 respondents who were ecstasy-naive at baseline. All respondents completed baseline questionnaires and underwent medical and neuropsychological examinations. At the end of a 11- to 26- month follow-up period in which they completed four additional questionnaires, 160 respondents remained (85.1%). A total of 65 participants (40.6%) took ecstasy for the first time during the follow-up period. This paper discusses the ethical dilemmas inherent in a study of this type and the specific problems and solutions that emerged in the sampling. The sampling was tightly constrained by our need to locate respondents who were potential future ecstasy users while also meeting strict medical and technical criteria. The 'intention to use' criterion proved to be a clear-cut inclusion rule that was practical to apply in the fieldwork.
Sampling Operations on Big Data
2015-11-29
gories. These include edge sampling methods where edges are selected by a predetermined criteria; snowball sampling methods where algorithms start... Sampling Operations on Big Data Vijay Gadepally, Taylor Herr, Luke Johnson, Lauren Milechin, Maja Milosavljevic, Benjamin A. Miller Lincoln...process and disseminate information for discovery and exploration under real-time constraints. Common signal processing operations such as sampling and
Approaches to Recruiting 'Hard-To-Reach' Populations into Re-search: A Review of the Literature.
Shaghaghi, Abdolreza; Bhopal, Raj S; Sheikh, Aziz
2011-01-01
'Hard-to-reach' is a term used to describe those sub-groups of the population that may be difficult to reach or involve in research or public health programmes. Application of a single term to call these sub-sections of populations implies a homogeneity within distinct groups, which does not necessarily exist. Different sampling techniques were introduced so far to recruit hard-to-reach populations. In this article, we have reviewed a range of ap-proaches that have been used to widen participation in studies. We performed a Pubmed and Google search for relevant English language articles using the keywords and phrases: (hard-to-reach AND population* OR sampl*), (hidden AND population* OR sample*) and ("hard to reach" AND population* OR sample*) and a consul-tation of the retrieved articles' bibliographies to extract empirical evidence from publications that discussed or examined the use of sampling techniques to recruit hidden or hard-to-reach populations in health studies. Reviewing the literature has identified a range of techniques to recruit hard-to-reach populations, including snowball sampling, respondent-driven sampling (RDS), indigenous field worker sampling (IFWS), facility-based sampling (FBS), targeted sampling (TS), time-location (space) sampling (TLS), conventional cluster sampling (CCS) and capture re-capture sampling (CR). The degree of compliance with a study by a certain 'hard-to-reach' group de-pends on the characteristics of that group, recruitment technique used and the subject of inter-est. Irrespective of potential advantages or limitations of the recruitment techniques reviewed, their successful use depends mainly upon our knowledge about specific characteristics of the target populations. Thus in line with attempts to expand the current boundaries of our know-ledge about recruitment techniques in health studies and their applications in varying situa-tions, we should also focus on possibly all contributing factors which may have an impact on participation rate within a defined population group.
Neoproterozoic cap-dolostone deposition in stratified glacial meltwater plume
NASA Astrophysics Data System (ADS)
Liu, Chao; Wang, Zhengrong; Raub, Timothy D.; Macdonald, Francis A.; Evans, David A. D.
2014-10-01
Neoproterozoic cap carbonates host distinctive geochemical and sedimentological features that reflect prevailing conditions in the aftermath of Snowball Earth. Interpretation of these features has remained contentious, with hypotheses hinging upon timescale and synchronicity of deposition, and whether or not geochemical signatures of cap carbonates represent those of a well-mixed ocean. Here we present new high-resolution Sr and Mg isotope results from basal Ediacaran cap dolostones in South Australia and Mongolia. Least-altered Sr and Mg isotope compositions of carbonates are identified through a novel incremental leaching technique that monitors the purity of a carbonate sample and the effects of diagenesis. These data can be explained by the formation of these cap dolostones involving two chemically distinct solutions, a glacial meltwater plume enriched in radiogenic Sr, and a saline ocean residue with relatively lower 87Sr/86Sr ratios. Model simulations suggest that these water bodies remained dynamically stratified during part of cap-dolostone deposition, most likely lasting for ∼8 thousand years. Our results can potentially reconcile previous conflicts between timescales estimated from physical mixing models and paleomagnetic constraints. Geochemical data from cap carbonates used to interpret the nature of Snowball Earth and its aftermath should be recast in terms of a chemically distinct meltwater plume.
Profile and birthing practices of Maranao traditional birth attendants.
Maghuyop-Butalid, Roselyn; Mayo, Norhanifa A; Polangi, Hania T
2015-01-01
This study determined the profile and birthing practices in both modern and traditional ways among Maranao traditional birth attendants (TBAs) in Lanao del Norte, Philippines. It employed a descriptive research design. The respondents were 50 Maranao TBAs selected through the snowball sampling technique. A questionnaire was developed by the researchers to identify the respondents' modern birthing practices utilizing the Essential Intrapartum and Newborn Care (EINC) Protocol. To determine their profile and traditional birthing practices, items from a previous study and the respondents' personal claims were adapted. This study shows that Maranao TBAs have less compliance to the EINC Protocol and they often practice the traditional birthing interventions, thus increasing the risk of complications to both mother and newborn.
Sampling Large Graphs for Anticipatory Analytics
2015-05-15
low. C. Random Area Sampling Random area sampling [8] is a “ snowball ” sampling method in which a set of random seed vertices are selected and areas... Sampling Large Graphs for Anticipatory Analytics Lauren Edwards, Luke Johnson, Maja Milosavljevic, Vijay Gadepally, Benjamin A. Miller Lincoln...systems, greater human-in-the-loop involvement, or through complex algorithms. We are investigating the use of sampling to mitigate these challenges
Uderstanding Snowball Earth Deglaciation
NASA Astrophysics Data System (ADS)
Abbot, D. S.
2012-12-01
Earth, a normally clement planet comfortably in its star's habitable zone, suffered global or nearly global glaciation at least twice during the Neoproterozoic era (at about 635 and 710 million years ago). Viewed in the context of planetary evolution, these pan-global glaciations (Snowball Earth events) were extremely rapid, lasting only a few million years. The dramatic effect of the Snowball Earth events on the development of the planet can be seen through their link to rises in atmospheric oxygen and evolutionary innovations. These potential catastrophes on an otherwise clement planet can be used to gain insight into planetary habitability more generally. Since Earth is not currently a Snowball, a sound deglaciation mechanism is crucial for the viability of the Snowball Earth hypothesis. The traditional deglaciation mechanism is a massive build up of CO2 due to reduced weathering during Snowball Earth events until tropical surface temperatures reach the melting point. Once initiated, such a deglaciation might happen on a timescale of only dozens of thousands of years and would thrust Earth from the coldest climate in its history to the warmest. Therefore embedded in Snowball Earth events is an even more rapid and dramatic environmental change. Early global climate model simulations raised doubt about whether Snowball Earth deglaciation could be achieved at a CO2 concentration low enough to be consistent with geochemical data, which represented a potential challenge to the Snowball Earth hypothesis. Over the past few years dust and clouds have emerged as the essential missing additional processes that would allow Snowball Earth deglaciation at a low enough CO2 concentration. I will discuss the dust and cloud mechanisms and the modeling behind these ideas. This effort is critical for the broader implications of Snowball Earth events because understanding the specific deglaciation mechanism determines whether similar processes could happen on other planets.
Rao, Amrita; Stahlman, Shauna; Hargreaves, James; Weir, Sharon; Edwards, Jessie; Rice, Brian; Kochelani, Duncan; Mavimbela, Mpumelelo; Baral, Stefan
2018-01-15
[This corrects the article DOI: 10.2196/publichealth.8116.]. ©Amrita Rao, Shauna Stahlman, James Hargreaves, Sharon Weir, Jessie Edwards, Brian Rice, Duncan Kochelani, Mpumelelo Mavimbela, Stefan Baral. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 15.01.2018.
Exploring How Health Professionals Create eHealth and mHealth Education Interventions
ERIC Educational Resources Information Center
Tamim, Suha R.; Grant, Michael M.
2016-01-01
This qualitative study aimed at exploring how health professionals use instructional design principles to create health education interventions. A purposeful sample of 12 participants was selected, using criterion and snowballing sampling strategies. Semi-structured interviews were conducted to collect data, which were later analyzed through…
Mapping the Structure of Semantic Memory
ERIC Educational Resources Information Center
Morais, Ana Sofia; Olsson, Henrik; Schooler, Lael J.
2013-01-01
Aggregating snippets from the semantic memories of many individuals may not yield a good map of an individual's semantic memory. The authors analyze the structure of semantic networks that they sampled from individuals through a new snowball sampling paradigm during approximately 6 weeks of 1-hr daily sessions. The semantic networks of individuals…
Career College Governance: A Study of the Faculty's Propensity to Participate
ERIC Educational Resources Information Center
King, Stephen H.
2012-01-01
This study investigated faculty perceptions of and propensity to participate in shared governance activities in proprietary, post-secondary educational institutions. The sample population for this study (n = 22) included adjunct and full-time faculty members and administrators selected through a snowball sampling method and initially inclusive of…
Transactional sex, condom and lubricant use among men who have sex with men in Lagos State, Nigeria.
Ayoola, Oluyemisi O; Sekoni, Adekemi O; Odeyemi, Kofoworola A
2013-12-01
Men who have unprotected sex with men may also have unprotected sex with women and thus serve as an epidemiological bridge for HIV to the general population. This cross sectional descriptive study assessed condom and lubricant use and practice of transactional sex among men who have sex with men (MSM) in Lagos state. Simple random sampling was used to select three community centres and snowball sampling technique was used to recruit 321 respondents. Almost half (50.9%) had received payment for sex while 45.4% had paid for sex in the past. Consistent condom use was practiced by 40.5% of respondents during the last 10 sexual encounters, 85.6% used lubricants mostly with condom, products used were KY jelly, body cream, saliva and Vaseline. There is need for behavioural change to reduce risky practices which predisposes this group of MSM to HIV and sexually transmitted infections.
Approaches to Recruiting ‘Hard-To-Reach’ Populations into Research: A Review of the Literature
Shaghaghi, Abdolreza; Bhopal, Raj S; Sheikh, Aziz
2011-01-01
Background: ‘Hard-to-reach’ is a term used to describe those sub-groups of the population that may be difficult to reach or involve in research or public health programmes. Application of a single term to call these sub-sections of populations implies a homogeneity within distinct groups, which does not necessarily exist. Different sampling techniques were introduced so far to recruit hard-to-reach populations. In this article, we have reviewed a range of approaches that have been used to widen participation in studies. Methods: We performed a Pubmed and Google search for relevant English language articles using the keywords and phrases: (hard-to-reach AND population* OR sampl*), (hidden AND population* OR sample*) and (“hard to reach” AND population* OR sample*) and a consultation of the retrieved articles’ bibliographies to extract empirical evidence from publications that discussed or examined the use of sampling techniques to recruit hidden or hard-to-reach populations in health studies. Results: Reviewing the literature has identified a range of techniques to recruit hard-to-reach populations, including snowball sampling, respondent-driven sampling (RDS), indigenous field worker sampling (IFWS), facility-based sampling (FBS), targeted sampling (TS), time-location (space) sampling (TLS), conventional cluster sampling (CCS) and capture re-capture sampling (CR). Conclusion: The degree of compliance with a study by a certain ‘hard-to-reach’ group depends on the characteristics of that group, recruitment technique used and the subject of interest. Irrespective of potential advantages or limitations of the recruitment techniques reviewed, their successful use depends mainly upon our knowledge about specific characteristics of the target populations. Thus in line with attempts to expand the current boundaries of our knowledge about recruitment techniques in health studies and their applications in varying situations, we should also focus on possibly all contributing factors which may have an impact on participation rate within a defined population group. PMID:24688904
ERIC Educational Resources Information Center
Oketch, Moses O.
2009-01-01
This article examines how recent changes, leading to a diversified supply in Kenya's university education system, is reflected in prospective students' aspirations, perceptions and preferences to undertake university education. The results, based on a combination of a convenience and snowball sampling of settings, within which random samples of…
The Service Learning Projects: Stakeholder Benefits and Potential Class Topics
ERIC Educational Resources Information Center
Rutti, Raina M.; LaBonte, Joanne; Helms, Marilyn Michelle; Hervani, Aref Agahei; Sarkarat, Sy
2016-01-01
Purpose: The purpose of this paper is to summarize the benefits of including a service learning project in college classes and focusses on benefits to all stakeholders, including students, community, and faculty. Design/methodology/approach: Using a snowball approach in academic databases as well as a nominal group technique to poll faculty, key…
Geophysics of an Oceanic Ice Shell on Snowball Earth
NASA Technical Reports Server (NTRS)
Gaidos, E. J.
2000-01-01
Kirschvink proposed Precambrian low-latitude glaciation could result in an albedo-driven catastrophic runaway to a "Snowball Earth" state in which pack ice up to 1 km thick covered the world ocean. The geophysical state of an ice crust on a Snowball Earth is examined.
Evolving Curricular Models in Culinary Arts: An Instrumental Case Study of a Technical Field
ERIC Educational Resources Information Center
Cossio, Allison
2016-01-01
The purpose of this research study was to examine how chefs and other individuals in the food industry understood the field of culinary arts. This study used an instrumental case study with purposeful sampling of multiple cases. Through a series of open-ended interviews using snowball-sampling strategy that concluded with 45 participants sharing…
Adaptive sampling in behavioral surveys.
Thompson, S K
1997-01-01
Studies of populations such as drug users encounter difficulties because the members of the populations are rare, hidden, or hard to reach. Conventionally designed large-scale surveys detect relatively few members of the populations so that estimates of population characteristics have high uncertainty. Ethnographic studies, on the other hand, reach suitable numbers of individuals only through the use of link-tracing, chain referral, or snowball sampling procedures that often leave the investigators unable to make inferences from their sample to the hidden population as a whole. In adaptive sampling, the procedure for selecting people or other units to be in the sample depends on variables of interest observed during the survey, so the design adapts to the population as encountered. For example, when self-reported drug use is found among members of the sample, sampling effort may be increased in nearby areas. Types of adaptive sampling designs include ordinary sequential sampling, adaptive allocation in stratified sampling, adaptive cluster sampling, and optimal model-based designs. Graph sampling refers to situations with nodes (for example, people) connected by edges (such as social links or geographic proximity). An initial sample of nodes or edges is selected and edges are subsequently followed to bring other nodes into the sample. Graph sampling designs include network sampling, snowball sampling, link-tracing, chain referral, and adaptive cluster sampling. A graph sampling design is adaptive if the decision to include linked nodes depends on variables of interest observed on nodes already in the sample. Adjustment methods for nonsampling errors such as imperfect detection of drug users in the sample apply to adaptive as well as conventional designs.
Xu, Yaomin; Guo, Xingyi; Sun, Jiayang; Zhao, Zhongming
2015-01-01
Motivation: Large-scale cancer genomic studies, such as The Cancer Genome Atlas (TCGA), have profiled multidimensional genomic data, including mutation and expression profiles on a variety of cancer cell types, to uncover the molecular mechanism of cancerogenesis. More than a hundred driver mutations have been characterized that confer the advantage of cell growth. However, how driver mutations regulate the transcriptome to affect cellular functions remains largely unexplored. Differential analysis of gene expression relative to a driver mutation on patient samples could provide us with new insights in understanding driver mutation dysregulation in tumor genome and developing personalized treatment strategies. Results: Here, we introduce the Snowball approach as a highly sensitive statistical analysis method to identify transcriptional signatures that are affected by a recurrent driver mutation. Snowball utilizes a resampling-based approach and combines a distance-based regression framework to assign a robust ranking index of genes based on their aggregated association with the presence of the mutation, and further selects the top significant genes for downstream data analyses or experiments. In our application of the Snowball approach to both synthesized and TCGA data, we demonstrated that it outperforms the standard methods and provides more accurate inferences to the functional effects and transcriptional dysregulation of driver mutations. Availability and implementation: R package and source code are available from CRAN at http://cran.r-project.org/web/packages/DESnowball, and also available at http://bioinfo.mc.vanderbilt.edu/DESnowball/. Contact: zhongming.zhao@vanderbilt.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25192743
ERIC Educational Resources Information Center
Curbow, Barbara; Bowie, Janice; Binko, JoAnn; Smith, Stephanie; Dreyling, Erin; McDonnell, Karen A.
2007-01-01
Using a snowball technique, in-depth interviews were conducted with 108 girls emanating from seven demographically dissimilar social networks. Girls were asked to classify 58 items as either a risk or protective factor for smoking initiation and then to assign an importance weighting to each. All items except one (worries about her weight) were…
Chen, Li-Chin; Lin, Chun-Chih; Han, Chin-Yen; Hsieh, Chun-Lan; Wu, Chiung-Jung Jo; Liang, Hwey-Fang
2018-03-01
This study aims to gain in-depth understanding of nurses' perspectives of working in an overcrowded emergency. Symbolic interactionism and Charmaz's construction of grounded theory were used. Purposive sampling at the start of the study and a further theoretical sampling by snowball technique were used to recruit 40 registered nurses (RN) to participate in in-depth, semi-structured interviews between May and November, 2014. Data analysis included analytic techniques of initial, focused and theoretical coding. Study findings showed searching for work role is derived by the themes of Finding the role of positioning in Emergency Department (ED), Recognizing causes of ED overcrowding, and Confined working environment. Nurses' work experience which represents the RNs not gained control over their work, as care actions influenced by the problematic overcrowded circumstance of the ED environment. The findings fill a gap in knowledge about how RNs experience their work role in the context of an overcrowded Emergency Department in Taiwan. Arising from the study result include taking account of nurses' perspectives when planning staff/patient ratios, strategies to reduce waiting time and ensure that clients receive appropriate care. Copyright © 2018. Published by Elsevier B.V.
Gyarmathy, V Anna; Johnston, Lisa G; Caplinskiene, Irma; Caplinskas, Saulius; Latkin, Carl A
2014-02-01
Respondent driven sampling (RDS) and incentivized snowball sampling (ISS) are two sampling methods that are commonly used to reach people who inject drugs (PWID). We generated a set of simulated RDS samples on an actual sociometric ISS sample of PWID in Vilnius, Lithuania ("original sample") to assess if the simulated RDS estimates were statistically significantly different from the original ISS sample prevalences for HIV (9.8%), Hepatitis A (43.6%), Hepatitis B (Anti-HBc 43.9% and HBsAg 3.4%), Hepatitis C (87.5%), syphilis (6.8%) and Chlamydia (8.8%) infections and for selected behavioral risk characteristics. The original sample consisted of a large component of 249 people (83% of the sample) and 13 smaller components with 1-12 individuals. Generally, as long as all seeds were recruited from the large component of the original sample, the simulation samples simply recreated the large component. There were no significant differences between the large component and the entire original sample for the characteristics of interest. Altogether 99.2% of 360 simulation sample point estimates were within the confidence interval of the original prevalence values for the characteristics of interest. When population characteristics are reflected in large network components that dominate the population, RDS and ISS may produce samples that have statistically non-different prevalence values, even though some isolated network components may be under-sampled and/or statistically significantly different from the main groups. This so-called "strudel effect" is discussed in the paper. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
ERIC Educational Resources Information Center
Amimo, Catherine Adhiambo
2016-01-01
This study investigated management of change in teacher education curriculum in Private universities in Kenya. The study employed a concurrent mixed methods design that is based on the use of both quantitative and qualitative approaches. A multi-stage sampling process which included purposive, convenience, cluster, and snowball sampling methods…
Teaching Math Online: Current Practices in Turkey
ERIC Educational Resources Information Center
Akdemir, Omur
2011-01-01
Changing nature of student population, developments in technology, and insufficient number of traditional universities have made online courses popular around the globe. This study was designed to investigate the current practices of teaching mathematics online in Turkish Universities through a qualitative inquiry. The snowball sampling method was…
Gyarmathy, V. Anna; Johnston, Lisa G.; Caplinskiene, Irma; Caplinskas, Saulius; Latkin, Carl A.
2014-01-01
Background Respondent driven sampling (RDS) and Incentivized Snowball Sampling (ISS) are two sampling methods that are commonly used to reach people who inject drugs (PWID). Methods We generated a set of simulated RDS samples on an actual sociometric ISS sample of PWID in Vilnius, Lithuania (“original sample”) to assess if the simulated RDS estimates were statistically significantly different from the original ISS sample prevalences for HIV (9.8%), Hepatitis A (43.6%), Hepatitis B (Anti-HBc 43.9% and HBsAg 3.4%), Hepatitis C (87.5%), syphilis (6.8%) and Chlamydia (8.8%) infections and for selected behavioral risk characteristics. Results The original sample consisted of a large component of 249 people (83% of the sample) and 13 smaller components with 1 to 12 individuals. Generally, as long as all seeds were recruited from the large component of the original sample, the simulation samples simply recreated the large component. There were no significant differences between the large component and the entire original sample for the characteristics of interest. Altogether 99.2% of 360 simulation sample point estimates were within the confidence interval of the original prevalence values for the characteristics of interest. Conclusions When population characteristics are reflected in large network components that dominate the population, RDS and ISS may produce samples that have statistically non-different prevalence values, even though some isolated network components may be under-sampled and/or statistically significantly different from the main groups. This so-called “strudel effect” is discussed in the paper. PMID:24360650
'It depends': medical residents' perspectives on working with nurses.
Weinberg, Dana B; Miner, Dianne Cooney; Rivlin, Leetal
2009-07-01
Using the theory of relational coordination, which holds that in high-pressure settings such as hospitals, high-quality communication and strong relationships are necessary for coordinated action, we sought to determine the quality of the nurse-physician relationship by examining the communication and interaction between nurses and residents from the residents' perspective. A sample of 20 medical and surgical residents, selected by a snowball sampling technique, were interviewed about the quality of their communication and relationships with nurses in the workplace. Residents' responses were influenced by their perceptions of nurses' cooperativeness and competence, and their impressions of nurses' professional preparation and demeanor varied widely. Although 19 of 20 residents reported instances of poor communication or problematic relationships with nurses, most believed that this posed no significant threat to patient care because the nurses' role, as they saw it, was one of simply following orders. Given the strong doubts some residents expressed about nurses' cooperativeness and competence, the nursing profession should consider strengthening nursing education and clearly delineating nurses' roles and competencies.
Uppal, Gina; Sibbald, Shannon L; Melling, James
2016-12-01
This study describes the ethnocultural influences associated with managing diabetes (Type 2) in a small sample of older Sikh immigrants in Toronto, Canada. The South Asian community, which includes Sikhs, is the fastest growing immigrant population, the second largest visible minority in Canada, and is five times more likely to have diabetes than their Canadian counterparts. The relationship between culture, immigration, and management of diabetes has been recognized, but research of how these areas intersect in the Sikh community is sparse. Data were collected using qualitative semi-structured interviews, and participants were recruited via purposive and snowball sampling techniques. Data were analysed using constant comparative methods. The complexities of diabetes management are organized in this study as the (1) external (2) internal and (3) actualized experiences participants faced navigating cultural dynamics, understanding their diagnosis, and interacting with health resources. An individual's diabetes diagnosis and treatment plan interacts with layers beyond the health system which must be understood in order to provide health care that is truly an empowering resource.
Self-esteem among eunuchs of Hazara Division, Pakistan.
Alvi, Sajid Mehmood; Turabi, Maleeka Rubab; Ali, Syeda Ayat-E-Zainab; Irfan, Muhammad Shoaib; Afridi, Maryam; Shah, Asghar Ali
2018-02-01
Self-esteem among eunuchs is highly influenced by a variety of factors. The aim of the current study was to investigate the differences in self-esteem of eunuchs on the basis of education, income, age and marital status. The study was conducted at the University of Haripur, Pakistan, from December 2015 to November 2016. A sample of 140 eunuchs was collected from different areas of Hazara division, through purposive and snowball sampling technique. A self-esteem scale with four sub-scales was used to measure the self-esteem of eunuchs. One-way analysis of variance was used to determine education level differences. The t-test was applied to find out the impact of demographics differences such as marital status, income level, and age on self-esteem of eunuchs. The scale used was found to be quite reliable with alpha coefficient of 0.85. The outcomes are significant and showed that educated, higher income, younger and unmarried eunuchs had higher self-esteem (p<0.05).
Strategy to increase Barangan Banana production in Kabupaten Deli Serdang
NASA Astrophysics Data System (ADS)
Adhany, I.; Chalil, D.; Ginting, R.
2018-02-01
This study was conducted to analyze internal and external factors in increasing Barangan Banana production in Kabupaten Deli Serdang. Samples were determined by snowball sampling technique and purposive sampling method. Using SWOT analysis method, this study found that there were 6 internal strategic factors and 9 external strategic factors. Among that strategic factors, support for production facilities appears as the most important internal strategic factor, while the demand for Barangan Banana. as the most important external strategic factor. Based on the importance and existing condition of these strategic factors, using support for production facilities and realization of supporting facilities with farming experience are the strategies covering strength-opportunity (SO), organizing mentoring to meet the demand for Barangan Banana are the strategies covering weakness-opportunity (WO), making use of funding support and subsidies to widen the land, using tissue culture seeds and facilities and infrastructures are the strategies covering strength-threat (ST), increas the funding support to widen the land, the use of tissue culture seeds and facilities and infrastructures are the strategies covering weakness-threat (WT) are discussed and proposed to increase Barangan Banana productivity in Kabupaten Deli Serdang.
No Snowball on Habitable Tidally Locked Planets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Checlair, Jade; Abbot, Dorian S.; Menou, Kristen, E-mail: jadecheclair@uchicago.edu
The TRAPPIST-1, Proxima Centauri, and LHS 1140 systems are the most exciting prospects for future follow-up observations of potentially inhabited planets. All of the planets orbit nearby M-stars and are likely tidally locked in 1:1 spin–orbit states, which motivates the consideration of the effects that tidal locking might have on planetary habitability. On Earth, periods of global glaciation (snowballs) may have been essential for habitability and remote signs of life (biosignatures) because they are correlated with increases in the complexity of life and in the atmospheric oxygen concentration. In this paper, we investigate the snowball bifurcation (sudden onset of globalmore » glaciation) on tidally locked planets using both an energy balance model and an intermediate-complexity global climate model. We show that tidally locked planets are unlikely to exhibit a snowball bifurcation as a direct result of the spatial pattern of insolation they receive. Instead, they will smoothly transition from partial to complete ice coverage and back. A major implication of this work is that tidally locked planets with an active carbon cycle should not be found in a snowball state. Moreover, this work implies that tidally locked planets near the outer edge of the habitable zone with low CO{sub 2} outgassing fluxes will equilibrate with a small unglaciated substellar region rather than cycling between warm and snowball states. More work is needed to determine how the lack of a snowball bifurcation might affect the development of life on a tidally locked planet.« less
No Snowball on Habitable Tidally Locked Planets
NASA Astrophysics Data System (ADS)
Checlair, Jade; Menou, Kristen; Abbot, Dorian S.
2017-08-01
The TRAPPIST-1, Proxima Centauri, and LHS 1140 systems are the most exciting prospects for future follow-up observations of potentially inhabited planets. All of the planets orbit nearby M-stars and are likely tidally locked in 1:1 spin–orbit states, which motivates the consideration of the effects that tidal locking might have on planetary habitability. On Earth, periods of global glaciation (snowballs) may have been essential for habitability and remote signs of life (biosignatures) because they are correlated with increases in the complexity of life and in the atmospheric oxygen concentration. In this paper, we investigate the snowball bifurcation (sudden onset of global glaciation) on tidally locked planets using both an energy balance model and an intermediate-complexity global climate model. We show that tidally locked planets are unlikely to exhibit a snowball bifurcation as a direct result of the spatial pattern of insolation they receive. Instead, they will smoothly transition from partial to complete ice coverage and back. A major implication of this work is that tidally locked planets with an active carbon cycle should not be found in a snowball state. Moreover, this work implies that tidally locked planets near the outer edge of the habitable zone with low CO2 outgassing fluxes will equilibrate with a small unglaciated substellar region rather than cycling between warm and snowball states. More work is needed to determine how the lack of a snowball bifurcation might affect the development of life on a tidally locked planet.
Improving the Climate for LGBTQ Students at an Historically Black University
ERIC Educational Resources Information Center
Lewis, Marilyn W.; Ericksen, Kirsten S.
2016-01-01
African American lesbian, gay, bisexual, transgender, and queer (LGBTQ) students attending an Historically Black College or University (HBCU) may experience bullying. Using snowball sampling, the authors recruited six LGBTQ students for a focus group to learn how they perceived their HBCU campus atmosphere toward LGBTQ students. Thirty faculty…
Open Adoption: Adoptive Parents' Reactions Two Decades Later
ERIC Educational Resources Information Center
Siegel, Deborah H.
2013-01-01
Unlike in the past, most adoption agencies today offer birth parents and adoptive parents the opportunity to share identifying information and have contact with each other. To understand the impacts of different open adoption arrangements, a qualitative descriptive study using a snowball sample of 44 adoptive parents throughout New England began…
School Nurses and Health Education: The Classroom Experience
ERIC Educational Resources Information Center
Klein, Julie; Sendall, Marguerite C.; Fleming, Marylou; Lidstone, John; Domocol, Michelle
2013-01-01
Objective: The aim of the study is to explore school nurses' experience of health education. Design: A qualitative approach, phenomenology was used to answer the question. Method: Sixteen participants were recruited through purposeful and snowball sampling. Participants undertook an audio-recorded interview which was transcribed and analysed.…
The Connections between Latino Ethnic Identity and Adult Experiences
ERIC Educational Resources Information Center
Torres, Vasti; Martinez, Sylvia; Wallace, Lisa D.; Medrano, Christianne I.; Robledo, Andrea L.; Hernandez, Ebelia
2012-01-01
This study considers the influence of adult experiences on the development of Latino ethnic identity. Using purposeful and snowball sampling, adult participants responded to open-ended questions about their understanding of being Latino. Analysis indicated that changes in the environment or life circumstances had the greatest effect on the…
ERIC Educational Resources Information Center
Hovardas, Tasos
2016-01-01
The study concentrated on an area in Greece with a multiplicity of sites for outdoor education. Informal networks of teachers were detected through a snowball technique and data were collected by means of a questionnaire and semi-structured interviews. A typology was first enriched to account for teacher interaction. This typology was then…
NASA Astrophysics Data System (ADS)
Dadic, Ruzica; Mullen, Peter C.; Schneebeli, Martin; Brandt, Richard E.; Warren, Stephen G.
2013-09-01
Spectral albedo was measured along a 6 km transect near the Allan Hills in East Antarctica. The transect traversed the sequence from new snow through old snow, firn, and white ice, to blue ice, showing a systematic progression of decreasing albedo at all wavelengths, as well as decreasing specific surface area (SSA) and increasing density. Broadband albedos under clear-sky range from 0.80 for snow to 0.57 for blue ice, and from 0.87 to 0.65 under cloud. Both air bubbles and cracks scatter sunlight; their contributions to SSA were determined by microcomputed tomography on core samples of the ice. Although albedo is governed primarily by the SSA (and secondarily by the shape) of bubbles or snow grains, albedo also correlates highly with porosity, which, as a proxy variable, would be easier for ice sheet models to predict than bubble sizes. Albedo parameterizations are therefore developed as a function of density for three broad wavelength bands commonly used in general circulation models: visible, near-infrared, and total solar. Relevance to Snowball Earth events derives from the likelihood that sublimation of equatorward-flowing sea glaciers during those events progressively exposed the same sequence of surface materials that we measured at Allan Hills, with our short 6 km transect representing a transect across many degrees of latitude on the Snowball ocean. At the equator of Snowball Earth, climate models predict thick ice, or thin ice, or open water, depending largely on their albedo parameterizations; our measured albedos appear to be within the range that favors ice hundreds of meters thick.
Decrease in Hysteresis of Planetary Climate for Planets with Long Solar Days
NASA Astrophysics Data System (ADS)
Abbot, Dorian S.; Bloch-Johnson, Jonah; Checlair, Jade; Farahat, Navah X.; Graham, R. J.; Plotkin, David; Popovic, Predrag; Spaulding-Astudillo, Francisco
2018-02-01
The ice-albedo feedback on rapidly rotating terrestrial planets in the habitable zone can lead to abrupt transitions (bifurcations) between a warm and a snowball (ice-covered) state, bistability between these states, and hysteresis in planetary climate. This is important for planetary habitability because snowball events may trigger rises in the complexity of life, but could also endanger complex life that already exists. Recent work has shown that planets tidally locked in synchronous rotation states will transition smoothly into the snowball state rather than experiencing bifurcations. Here we investigate the structure of snowball bifurcations on planets that are tidally influenced, but not synchronously rotating, so that they experience long solar days. We use PlaSIM, an intermediate-complexity global climate model, with a thermodynamic mixed layer ocean and the Sun’s spectrum. We find that the amount of hysteresis (the range in stellar flux for which there is bistability in climate) is significantly reduced for solar days with lengths of tens of Earth days, and disappears for solar days of hundreds of Earth days. These results suggest that tidally influenced planets orbiting M and K stars that are not synchronously rotating could have much less hysteresis associated with the snowball bifurcations than they would if they were rapidly rotating. This implies that the amount of time it takes them to escape a snowball state via CO2 outgassing would be greatly reduced, as would the period of cycling between the warm and snowball state if they have low CO2 outgassing rates.
The Pace of Hybrid Incompatibility Evolution in House Mice.
Wang, Richard J; White, Michael A; Payseur, Bret A
2015-09-01
Hybrids between species are often sterile or inviable. This form of reproductive isolation is thought to evolve via the accumulation of mutations that interact to reduce fitness when combined in hybrids. Mathematical formulations of this "Dobzhansky-Muller model" predict an accelerating buildup of hybrid incompatibilities with divergence time (the "snowball effect"). Although the Dobzhansky-Muller model is widely accepted, the snowball effect has only been tested in two species groups. We evaluated evidence for the snowball effect in the evolution of hybrid male sterility among subspecies of house mice, a recently diverged group that shows partial reproductive isolation. We compared the history of subspecies divergence with patterns of quantitative trait loci (QTL) detected in F2 intercrosses between two pairs of subspecies (Mus musculus domesticus with M. m. musculus and M. m. domesticus with M. m. castaneus). We used a recently developed phylogenetic comparative method to statistically measure the fit of these data to the snowball prediction. To apply this method, QTL were partitioned as either shared or unshared in the two crosses. A heuristic partitioning based on the overlap of QTL confidence intervals produced unambiguous support for the snowball effect. An alternative approach combining data among crosses favored the snowball effect for the autosomes, but a linear accumulation of incompatibilities for the X chromosome. Reasoning that the X chromosome analyses are complicated by low mapping resolution, we conclude that hybrid male sterility loci have snowballed in house mice. Our study illustrates the power of comparative genetic mapping for understanding mechanisms of speciation. Copyright © 2015 by the Genetics Society of America.
Automatic evidence retrieval for systematic reviews.
Choong, Miew Keen; Galgani, Filippo; Dunn, Adam G; Tsafnat, Guy
2014-10-01
Snowballing involves recursively pursuing relevant references cited in the retrieved literature and adding them to the search results. Snowballing is an alternative approach to discover additional evidence that was not retrieved through conventional search. Snowballing's effectiveness makes it best practice in systematic reviews despite being time-consuming and tedious. Our goal was to evaluate an automatic method for citation snowballing's capacity to identify and retrieve the full text and/or abstracts of cited articles. Using 20 review articles that contained 949 citations to journal or conference articles, we manually searched Microsoft Academic Search (MAS) and identified 78.0% (740/949) of the cited articles that were present in the database. We compared the performance of the automatic citation snowballing method against the results of this manual search, measuring precision, recall, and F1 score. The automatic method was able to correctly identify 633 (as proportion of included citations: recall=66.7%, F1 score=79.3%; as proportion of citations in MAS: recall=85.5%, F1 score=91.2%) of citations with high precision (97.7%), and retrieved the full text or abstract for 490 (recall=82.9%, precision=92.1%, F1 score=87.3%) of the 633 correctly retrieved citations. The proposed method for automatic citation snowballing is accurate and is capable of obtaining the full texts or abstracts for a substantial proportion of the scholarly citations in review articles. By automating the process of citation snowballing, it may be possible to reduce the time and effort of common evidence surveillance tasks such as keeping trial registries up to date and conducting systematic reviews.
The Pace of Hybrid Incompatibility Evolution in House Mice
Wang, Richard J.; White, Michael A.; Payseur, Bret A.
2015-01-01
Hybrids between species are often sterile or inviable. This form of reproductive isolation is thought to evolve via the accumulation of mutations that interact to reduce fitness when combined in hybrids. Mathematical formulations of this “Dobzhansky–Muller model” predict an accelerating buildup of hybrid incompatibilities with divergence time (the “snowball effect”). Although the Dobzhansky–Muller model is widely accepted, the snowball effect has only been tested in two species groups. We evaluated evidence for the snowball effect in the evolution of hybrid male sterility among subspecies of house mice, a recently diverged group that shows partial reproductive isolation. We compared the history of subspecies divergence with patterns of quantitative trait loci (QTL) detected in F2 intercrosses between two pairs of subspecies (Mus musculus domesticus with M. m. musculus and M. m. domesticus with M. m. castaneus). We used a recently developed phylogenetic comparative method to statistically measure the fit of these data to the snowball prediction. To apply this method, QTL were partitioned as either shared or unshared in the two crosses. A heuristic partitioning based on the overlap of QTL confidence intervals produced unambiguous support for the snowball effect. An alternative approach combining data among crosses favored the snowball effect for the autosomes, but a linear accumulation of incompatibilities for the X chromosome. Reasoning that the X chromosome analyses are complicated by low mapping resolution, we conclude that hybrid male sterility loci have snowballed in house mice. Our study illustrates the power of comparative genetic mapping for understanding mechanisms of speciation. PMID:26199234
Emery, Sherry; Lee, Jungwha; Curry, Susan J; Johnson, Tim; Sporer, Amy K; Mermelstein, Robin; Flay, Brian; Warnecke, Richard
2010-02-01
Surveys of community-based programs are difficult to conduct when there is virtually no information about the number or locations of the programs of interest. This article describes the methodology used by the Helping Young Smokers Quit (HYSQ) initiative to identify and profile community-based youth smoking cessation programs in the absence of a defined sample frame. We developed a two-stage sampling design, with counties as the first-stage probability sampling units. The second stage used snowball sampling to saturation, to identify individuals who administered youth smoking cessation programs across three economic sectors in each county. Multivariate analyses modeled the relationship between program screening, eligibility, and response rates and economic sector and stratification criteria. Cumulative logit models analyzed the relationship between the number of contacts in a county and the number of programs screened, eligible, or profiled in a county. The snowball process yielded 9,983 unique and traceable contacts. Urban and high-income counties yielded significantly more screened program administrators; urban counties produced significantly more eligible programs, but there was no significant association between the county characteristics and program response rate. There is a positive relationship between the number of informants initially located and the number of programs screened, eligible, and profiled in a county. Our strategy to identify youth tobacco cessation programs could be used to create a sample frame for other nonprofit organizations that are difficult to identify due to a lack of existing directories, lists, or other traditional sample frames.
NASA Astrophysics Data System (ADS)
Dadic, R.; Mullen, P.; Schneebeli, M.; Brandt, R. E.; Fitzpatric, M.; Carns, R.; Warren, S. G.
2012-04-01
The albedos of snow and ice surfaces are, because of their positive feedback, crucial to the initiation, continuation, and termination of a snowball event, as well as for determining the ice thickness on the ocean. Despite the name, Snowball Earth would not have been entirely snow-covered. As on modern Earth, evaporation would exceed precipitation over much of the tropical ocean. After a transient period with sea ice, the dominant ice type would probably be sea-glaciers flowing in from higher latitude. As they flowed equatorward into the tropical region of net sublimation, their surface snow and subsurface firn would sublimate away, exposing bare glacier ice to the atmosphere and to solar radiation. This ice would be freshwater (meteoric) ice, which originated from snow and firn, so it would contain numerous air bubbles, which determine the albedo. The modern surrogate for this type of ice (glacier ice exposed by pure sublimation, which has never experienced melting), are the bare-ice surfaces of the East Antarctic Ice Sheet near the Trans-Antarctic Mountains. These areas have been well mapped because of their importance in the search for meteorites. A transect across an icefield can potentially sample ice of different ages that has traveled to different depths en route to the sublimation front. We examined a 6-km transect from snow to ice near the Allan Hills (77 S, 158 E, 2000 m ASL), measuring spectral albedo and collecting 1-m core samples. This short transect is a surrogate of a north-south transect across many degrees of latitude on the Snowball ocean. Surfaces on the transect transitioned through the sequence: new snow - old snow - firn - young white ice - old blue ice. The transect from snow to ice showed a systematic progression of decreasing albedo at all wavelengths, as well as decreasing specific surface area (SSA; ratio of air-ice interface area to ice mass) and increasing density. The measured spectral albedos are integrated over wavelength and weighted by the spectral solar flux to obtain broadband albedos. These range from 0.8 for snow to 0.55 for blue ice. Although what determines the albedo is the SSA of bubbles or snow grains, the broadband albedo also shows a systematic relation to the snow or ice density, suggesting that density might serve as a surrogate variable that will be easier to predict than SSA in an ice-sheet model, using a parameterization for firn densification. The ice cores were analyzed by micro-CT (computer tomography) for bubble morphology, cracks (mainly thermal cracks), and SSA. The SSA is used in a radiative transfer model to explain the measured albedo spectra. We found that thermal cracks in the Allan Hills may be more important than in the equatorial region of Snowball Earth. We tried to separate the effects of cracks from original air bubbles by separately computing their individual SSAs in the CT images, and using those SSAs in the albedo model. These methods allow us to estimate a range of albedos for the different possible regions and climatic conditions on low latitudes of Snowball Earth.
A Comparison of Treatment Integrity Assessment Methods for Behavioral Intervention
ERIC Educational Resources Information Center
Koh, Seong A.
2010-01-01
The purpose of this study was to examine the similarity of outcomes from three different treatment integrity (TI) methods, and to identify the method which best corresponded to the assessment of a child's behavior. Six raters were recruited through individual contact via snowball sampling. A modified intervention component list and 19 video clips…
The Relationship of Self-Awareness to Leadership Effectiveness for Experienced Leaders
ERIC Educational Resources Information Center
Sullivan, Patricia A.
2017-01-01
The purpose of this research was to investigate the relationship between leaders' self-awareness and their effectiveness. The population included leaders with at least five years of experience in a leadership role. Participants were recruited by snowball sampling methods; the researcher used a diverse network of professionals to recruit other…
Reasons for Dropout for Vocational High School Students
ERIC Educational Resources Information Center
Tas, Ali; Selvitopu, Abdullah; Bora, Veysel; Demirkaya, Yusuf
2013-01-01
This study aimed to determine the reasons for dropout for persons who have not completed vocational education programme and left school without a diploma. By using snowball sampling method, 19 persons, willing to participate in the study, were reached. Data were obtained by semi structured interview forms. In data analysis process, inductive…
ERIC Educational Resources Information Center
Hunter, Carla D.
2008-01-01
Cultural worldviews and perceived racial discrimination were examined among Americans (n = 106) and British Caribbean Americans (n = 95), both of African descent, who were recruited through university student organizations, community organizations, and snowball sampling. Consistent with public perceptions of differences in the experience of race…
Sea-ice dynamics strongly promote Snowball Earth initiation and destabilize tropical sea-ice margins
NASA Astrophysics Data System (ADS)
Voigt, A.; Abbot, D. S.
2012-12-01
The Snowball Earth bifurcation, or runaway ice-albedo feedback, is defined for particular boundary conditions by a critical CO2 and a critical sea-ice cover (SI), both of which are essential for evaluating hypotheses related to Neoproterozoic glaciations. Previous work has shown that the Snowball Earth bifurcation, denoted as (CO2, SI)*, differs greatly among climate models. Here, we study the effect of bare sea-ice albedo, sea-ice dynamics and ocean heat transport on (CO2, SI)* in the atmosphere-ocean general circulation model ECHAM5/MPI-OM with Marinoan (~ 635 Ma) continents and solar insolation (94% of modern). In its standard setup, ECHAM5/MPI-OM initiates a~Snowball Earth much more easily than other climate models at (CO2, SI)* ≈ (500 ppm, 55%). Replacing the model's standard bare sea-ice albedo of 0.75 by a much lower value of 0.45, we find (CO2, SI)* ≈ (204 ppm, 70%). This is consistent with previous work and results from net evaporation and local melting near the sea-ice margin. When we additionally disable sea-ice dynamics, we find that the Snowball Earth bifurcation can be pushed even closer to the equator and occurs at a hundred times lower CO2: (CO2, SI)* ≈ (2 ppm, 85%). Therefore, the simulation of sea-ice dynamics in ECHAM5/MPI-OM is a dominant determinant of its high critical CO2 for Snowball initiation relative to other models. Ocean heat transport has no effect on the critical sea-ice cover and only slightly decreases the critical CO2. For disabled sea-ice dynamics, the state with 85% sea-ice cover is stabilized by the Jormungand mechanism and shares characteristics with the Jormungand climate states. However, there is no indication of the Jormungand bifurcation and hysteresis in ECHAM5/MPI-OM. The state with 85% sea-ice cover therefore is a soft Snowball state rather than a true Jormungand state. Overall, our results demonstrate that differences in sea-ice dynamics schemes can be at least as important as differences in sea-ice albedo for causing the spread in climate models' estimates of the Snowball Earth bifurcation. A detailed understanding of Snowball Earth initiation therefore requires future research on sea-ice dynamics to determine which model's simulation is most realistic.
Dynamics of a Snowball Earth ocean.
Ashkenazy, Yosef; Gildor, Hezi; Losch, Martin; Macdonald, Francis A; Schrag, Daniel P; Tziperman, Eli
2013-03-07
Geological evidence suggests that marine ice extended to the Equator at least twice during the Neoproterozoic era (about 750 to 635 million years ago), inspiring the Snowball Earth hypothesis that the Earth was globally ice-covered. In a possible Snowball Earth climate, ocean circulation and mixing processes would have set the melting and freezing rates that determine ice thickness, would have influenced the survival of photosynthetic life, and may provide important constraints for the interpretation of geochemical and sedimentological observations. Here we show that in a Snowball Earth, the ocean would have been well mixed and characterized by a dynamic circulation, with vigorous equatorial meridional overturning circulation, zonal equatorial jets, a well developed eddy field, strong coastal upwelling and convective mixing. This is in contrast to the sluggish ocean often expected in a Snowball Earth scenario owing to the insulation of the ocean from atmospheric forcing by the thick ice cover. As a result of vigorous convective mixing, the ocean temperature, salinity and density were either uniform in the vertical direction or weakly stratified in a few locations. Our results are based on a model that couples ice flow and ocean circulation, and is driven by a weak geothermal heat flux under a global ice cover about a kilometre thick. Compared with the modern ocean, the Snowball Earth ocean had far larger vertical mixing rates, and comparable horizontal mixing by ocean eddies. The strong circulation and coastal upwelling resulted in melting rates near continents as much as ten times larger than previously estimated. Although we cannot resolve the debate over the existence of global ice cover, we discuss the implications for the nutrient supply of photosynthetic activity and for banded iron formations. Our insights and constraints on ocean dynamics may help resolve the Snowball Earth controversy when combined with future geochemical and geological observations.
Kopp, Robert E; Kirschvink, Joseph L; Hilburn, Isaac A; Nash, Cody Z
2005-08-09
Although biomarker, trace element, and isotopic evidence have been used to claim that oxygenic photosynthesis evolved by 2.8 giga-annum before present (Ga) and perhaps as early as 3.7 Ga, a skeptical examination raises considerable doubt about the presence of oxygen producers at these times. Geological features suggestive of oxygen, such as red beds, lateritic paleosols, and the return of sedimentary sulfate deposits after a approximately 900-million year hiatus, occur shortly before the approximately 2.3-2.2 Ga Makganyene "snowball Earth" (global glaciation). The massive deposition of Mn, which has a high redox potential, practically requires the presence of environmental oxygen after the snowball. New age constraints from the Transvaal Supergroup of South Africa suggest that all three glaciations in the Huronian Supergroup of Canada predate the Snowball event. A simple cyanobacterial growth model incorporating the range of C, Fe, and P fluxes expected during a partial glaciation in an anoxic world with high-Fe oceans indicates that oxygenic photosynthesis could have destroyed a methane greenhouse and triggered a snowball event on time-scales as short as 1 million years. As the geological evidence requiring oxygen does not appear during the Pongola glaciation at 2.9 Ga or during the Huronian glaciations, we argue that oxygenic cyanobacteria evolved and radiated shortly before the Makganyene snowball.
Constructing a nurse appraisal form: A Delphi technique study
Zaghloul, Ashraf Ahmad Zaher; AlSokair, May Kosay
2008-01-01
Objective The study was conducted with the aim to construct a unified nurse appraisal format to be used at hospitals performing under different healthcare organizations in the Eastern Province in the Kingdom of Saudi Arabia. Methodology The study included hospitals representing different healthcare organizations within the Eastern Province. The target population included Hospital head nurses and nurse supervisors and the snowball sampling technique was employed to select the panel subjects. Results The final draft resulted into the agreed upon performance dimensions which included namely; quality standards, work habits, supervision/leadership, staff relations and interpersonal skills, attendance and punctuality, problem solving, oral communication, productivity results, coordination, innovation, record keeping. Conclusion Nurse managers have to continuously assess competence of practicing nurses to assure qualified and safe patient care. A nurse appraisal form was constructed concurrently with this study results and was proposed to be used at all Eastern Region hospitals. This study is considered an initial step for further efforts and studies to be conducted to reach both national and international nursing appraisal dimensions and unify them for the sake of best health promotion. PMID:21197327
Investigating the Equatorial Gaps in Snowball Earth Sea Glaciers
NASA Astrophysics Data System (ADS)
Spaulding-Astudillo, F.; Ashkenazy, Y.; Tziperman, E.; Abbot, D. S.
2017-12-01
The way photosynthetic life survived the Neoproterozoic Snowball Earth events is still a matter of debate that has deep implications for planetary habitability. One option is that gaps in thick, semi-global ice coverage (sea glaciers) could be maintained at the equator by ocean-ice-atmosphere dynamics. We investigate this idea by modifying a global ocean-thick-marine-ice model developed for modeling Neoproterozoic Snowball Events to account for gaps in thick ice and interactions with atmospheric dynamics. Our hypothesis is that in the parameter regime that allows for sea glacier flow, ice flow will make gaps in the thick ice, and therefore an open ocean solution, less likely. This would suggest that oases in thick ice are a more viable survival mechanism for photosynthetic life during a Snowball Earth event.
The Perceived Consequences of Gold Mining in Postwar El Salvador: A Qualitative Study.
Zakrison, Tanya L; Cabezas, Pedro; Valle, Evan; Kornfeld, Julie; Muntaner, Carles; Soklaridis, Sophie
2015-11-01
We investigated themes related to the health and environmental impacts of gold mining in El Salvador. Over a 1-month period in 2013, we conducted focus groups (n = 32 participants in total) and individual semistructured interviews (n = 11) with community leaders until we achieved thematic saturation. Data collection took place in 4 departments throughout the country. We used a combination of criterion-purposive and snowballing sampling techniques to identify participants. Multiple themes emerged: (1) the fallacy of economic development; (2) critique of mining activities; (3) the creation of mining-related violence, with parallels to El Salvador's civil war; and (4) solutions and alternatives to mining activity. Solutions involved the creation of cooperative microenterprises for sustainable economic growth, political empowerment within communities, and development of local participatory democracies. Gold mining in El Salvador is perceived as a significant environmental and public health threat. Local solutions may be applicable broadly.
Overcoming Barriers to Integrating Behavioral Health and Primary Care Services
Grazier, Kyle L.; Smiley, Mary L.; Bondalapati, Kirsten S.
2016-01-01
Objective: Despite barriers, organizations with varying characteristics have achieved full integration of primary care services with providers and services that identify, treat, and manage those with mental health and substance use disorders. What are the key factors and common themes in stories of this success? Methods: A systematic literature review and snowball sampling technique was used to identify organizations. Site visits and key informant interviews were conducted with 6 organizations that had over time integrated behavioral health and primary care services. Case studies of each organization were independently coded to identify traits common to multiple organizations. Results: Common characteristics include prioritized vulnerable populations, extensive community collaboration, team approaches that included the patient and family, diversified funding streams, and data-driven approaches and practices. Conclusions: While significant barriers to integrating behavioral health and primary care services exist, case studies of organizations that have successfully overcome these barriers share certain common factors. PMID:27380923
National Delphi study to determine competencies for nursing leadership in public health.
Misener, T R; Alexander, J W; Blaha, A J; Clarke, P N; Cover, C M; Felton, G M; Fuller, S G; Herman, J; Rodes, M M; Sharp, H F
1997-01-01
To identify competencies needed by nurse leaders in public health programs. Five-round national Delphi. Convenience sample of members of major public health nursing associations and nurse and non-nurse public health leaders in the USA. Mailed survey in 1994-1995 using a modified snowball technique based on a modification of the Pew Foundation health professions' competencies for Round 1. Four additional rounds produced consensus. Initially, 62 competencies were identified. Factor analysis resulted in four factors: political competencies, business acumen, program leadership, and management capabilities; 57 competencies were clustered in the four groupings and accounted for 91.4% of the variance. Graduate schools in nursing and public health must prepare students with broad-based competencies from a variety of disciplines. Findings of this national survey provide a database for curriculum development and evaluation of programs to prepare nurse leaders for roles in public health-based delivery systems.
The Independent Living Movement in Asia: Solidarity from Japan
ERIC Educational Resources Information Center
Hayashi, Reiko; Okuhira, Masako
2008-01-01
Independent living movements of disabled people are emerging in Asian countries, supported by independent living centres (ILCs) in Japan. A study was conducted in Japan to explore the impact of the training program offered by Japanese ILCs to disabled people from other Asian countries. A sample of 35 people was selected by a snowballing method.…
ERIC Educational Resources Information Center
Dharod, Jigna M.; Croom, Jamar E.; Sady, Christine G.
2013-01-01
Objective: To examine the association between food insecurity, dietary intake, and body mass index among Somali refugee women living in the United States. Methods: Cross-sectional study utilizing the snowball sampling method. Results: Most (67%) participants experienced some level of food insecurity, which was common among recent arrivals and…
Experience of Being Gay, Lesbian or Bisexual at an Australian Medical School: A Qualitative Study
ERIC Educational Resources Information Center
Chur-Hansen, Anna
2004-01-01
Six undergraduate students were interviewed in a qualitative study about their experiences as gay, lesbian or bisexual students studying Medicine. Informants, who were identified by snowball sampling, spoke about their experiences both freely and in response to a series of prompt questions derived from previous research. The transcribed interviews…
ERIC Educational Resources Information Center
Gollenberg, Audra; Fendley, Kim
2018-01-01
Sudden infant death syndrome (SIDS) remains a leading cause of infant death in the United States, and in Virginia. We sought to gauge the perceptions among community-identified stakeholders regarding community resource needs to reduce SIDS. Snowball sampling identified important community stakeholders to be interviewed as key informants. A…
Physical Activity and Older Adults: Expert Consensus for a New Research Agenda
ERIC Educational Resources Information Center
Hughes, Susan L.; Leith, Katherine H.; Marquez, David X.; Moni, Gwen; Nguyen, Huong Q.; Desai, Pankaja; Jones, Dina L.
2011-01-01
Purpose: This study sought to advance the state of knowledge regarding physical activity and aging by identifying areas of agreement among experts regarding topics that are well understood versus those that are in urgent need of continued research efforts. Design and methods: We used a web-based survey with snowball sampling to identify 348…
ERIC Educational Resources Information Center
Erk, Tiffany
2013-01-01
The purpose of this study is to identify how low-SES women who are providing primary childcare for children ages 0-10 experience higher education. In-depth phenomenological interviewing combined with document analysis were the methods utilized. This exploration used a purposive/snowball sample of low-SES mothers who were making satisfactory…
An Exploration of How Elementary School Principals Approach the Student Retention Decision Process
ERIC Educational Resources Information Center
Martinez-Hicks, Laura M.
2012-01-01
This is a constructivist grounded theory study investigating how elementary principals approach the student retention decision process in their schools. Twenty-two elementary principals participated in the study using a selective or snowball sampling method. Principals worked in one of three districts in a mid-Atlantic state and had experience as…
ERIC Educational Resources Information Center
Punyanunt-Carter, Narissra; Carter, Stacy
2015-01-01
This study examined the specific interpersonal communication styles and behaviors of advisors and the expectations they have on their advisee's level of satisfaction, as well as what characteristics lead to higher relational satisfaction in the advisor-advisee relationship. A combination of convenience and snowball sampling were utilized to obtain…
ERIC Educational Resources Information Center
Karakus, Fatma; Uyar, Melis Yesilpinar; Balbag, Nur Leman
2017-01-01
The purpose of this study was to determine teachers' educational needs regarding school education projects within the scope of Erasmus+ programme. In the study, the case study method, one of qualitative research designs, was used. The participants were determined using the snowball sampling method, and eight secondary school teachers took part in…
Investigating Climate at an Inland Sea During Snowball Earth
NASA Astrophysics Data System (ADS)
Campbell, A. J.; Bitz, C. M.; Warren, S. G.; Waddington, E. D.
2013-12-01
During the Neoproterozoic, the Earth's oceans may have been completely covered with thick ice, during periods commonly called Snowball Earth events. The Snowball Earth environment would seemingly have prohibited the survival of photosynthetic eukaryotic algae; however, these organisms were alive immediately prior to and immediate subsequent to these periods. Where on a Snowball Earth, or a Snowball-like exoplanet, could photosynthetic eukaryotic algae survive? Recent research, in attempt to reconcile this paradox, has demonstrated that narrow channels connected the ocean, called inland seas, could have provided refugia for photosynthetic eukaryotic algae during Snowball Earth events. Narrow channels could have restricted the flow of ocean-derived ice, called sea glaciers, diminishing sea-glacier penetration into these channels. Provided certain climate conditions and channel geometries, this diminished sea-glacier penetration would have allowed for either open water or thin sea ice, at the far end of these channels. A channel with open water or thin sea ice would provide the conditions needed for survival of photosynthetic eukaryotic algae. Here we test whether the climate needed to prevent sea-glacier penetration, could have existed in the special inland sea environment. Previous climate modeling of Snowball Earth has shown that tropical regions would have likely been warmer than the global average and would have experienced net sublimation at the surface. An inland sea located in the tropics would be surrounded by land that is bare and free from snow, while the inland sea itself would be either ice-covered or open water. With these conditions the inland sea would likely have a high albedo, while the surrounding bare land, would have a lower albedo. This albedo contrast could cause the climate over an inland sea to be warmer than the climate over the ice-covered ocean at the same latitude. We calculate the surface temperature and sublimation rate at an inland sea using the Community Earth System Model. By using idealized continent configurations and surface conditions and by adjusting the position and size of the inland sea, we establish the range and probability of achievable inland-sea climates in order to determine if inland seas could have been viable refugia for photosynthetic eukaryotic algae during Snowball Earth Events.
High-Albedo Salt Crusts on the Tropical Ocean of Snowball Earth: Measurements and Modeling
NASA Astrophysics Data System (ADS)
Carns, R.; Light, B.; Warren, S. G.
2014-12-01
During a Snowball Earth event, almost all of the ocean surface first freezes as sea ice. As in modern sea ice, trapped inclusions of liquid brine permeate the ice cover. As the ice grows and cools, salt crystals precipitate within the inclusions. At -23C, the most abundant salt in seawater, sodium chloride, begins to precipitate as the dihydrate mineral hydrohalite (NaCl·2H2O). Crystals of hydrohalite within the sea ice scatter light. Measurements of cold, natural sea ice show a broadband albedo increase of 10-20% when salt precipitates. Such snow-free natural sea ice with a surface temperature below -23C is rare on modern Earth, but would have been common in tropical regions of a Snowball Earth where evaporation exceeded precipitation. The persistent cold and lack of summer melt on the Snowball ocean surface, combined with net evaporation, is hypothesized to yield lag deposits of hydrohalite crystals on the ice surface. To investigate this process, we prepared laboratory-grown sea ice in a 1000 liter tank in a walk-in freezer laboratory. The ice was cooled below -23 C and the surface sprayed with a 23% NaCl solution to create a layer of hydrohalite-enriched ice, a proxy for lag deposits that would have formed over long periods of surface sublimation. We have developed a novel technique for measuring the spectral albedo of ice surfaces in the laboratory; this technique was used to monitor the evolution of the surface albedo of our salt crust as the ice matrix sublimated away leaving a layer of fine-grained hydrohalite crystals. Measurements of this hydrohalite surface crust show a very high albedo, comparable to fresh snow at visible wavelengths and significantly larger than fresh snow at near infrared wavelengths. Broadband albedos are 0.55 for bare artificial sea ice at -30C, 0.75 for ice containing 25% hydrohalite by volume, 0.84 after five days of desiccation and 0.93 after 47 days of desiccation. Using our laboratory measurements, along with estimates of grain size and crust optical depth, as inputs to Mie scattering and radiative transfer models allowed us to infer the imaginary refractive index of hydrohalite. The model can calculate albedo for pure hydrohalite crusts of varying thickness and for mixtures of ice and hydrohalite. A parameterization is presented for albedo as a function of the thickness of the hydrohalite crust.
Snowball Earth prevention by dissolved organic carbon remineralization.
Peltier, W Richard; Liu, Yonggang; Crowley, John W
2007-12-06
The 'snowball Earth' hypothesis posits the occurrence of a sequence of glaciations in the Earth's history sufficiently deep that photosynthetic activity was essentially arrested. Because the time interval during which these events are believed to have occurred immediately preceded the Cambrian explosion of life, the issue as to whether such snowball states actually developed has important implications for our understanding of evolutionary biology. Here we couple an explicit model of the Neoproterozoic carbon cycle to a model of the physical climate system. We show that the drawdown of atmospheric oxygen into the ocean, as surface temperatures decline, operates so as to increase the rate of remineralization of a massive pool of dissolved organic carbon. This leads directly to an increase of atmospheric carbon dioxide, enhanced greenhouse warming of the surface of the Earth, and the prevention of a snowball state.
Snowball Earth: Response of the biosphere?
NASA Astrophysics Data System (ADS)
Runnegar, B.
2001-05-01
Snowball Earth is a script for global catastrophe that rivals giant impact theories in the likely severity of its environmental effects. This is particularly true for the "hard" version of the hypothesis, which requires the atmosphere to be effectively isolated from the ocean so that its carbon dioxide concentration can build up to the level ( ~100 PAL) ultimately required to melt the ice. However, coupled GCM-EMB models (Hyde et al. Nature 405, 425-430; Crowley & Hyde, GRL 28, 283-286) allow equatorial open water solutions under plausible Neoproterozoic conditions. These "softer" scenarios are more appealing if one considers the possible effects of snowball Earth episodes on the global biosphere. The meager Neoproterozoic fossil record makes it difficult to observe the biospheric response directly, but we know from evolutionary trees constructed from aligned protein and DNA sequences from living organisms, calibrated by the fossil record, that many lines of descent passed through the Cryogenian glacial periods. They include various kinds of prokaryotic and eukaryotic algae, a range of protists, and probably, a number of different kinds of animals and fungi. In addition, most of the microbial groups shown on comprehensive 16S rRNA trees have molecular clock ages that predate the snowball episodes. As the global environmental perturbations associated with the "hard" snowball hypothesis (freezing temperatures; huge and rapid changes in temperature; sudden carbon dioxide overload) are thought to have been biologically limiting during the Phanerozoic, the inferred response of the biosphere to Neoprotereozic glaciations may, indeed, provide a way of testing alternative snowball Earth scenarios.
Experiences of Children With Gay Fathers.
Perrin, Ellen C; Pinderhughes, Ellen E; Mattern, Kathryn; Hurley, Sean M; Newman, Rachel A
2016-12-01
An online survey was distributed via snowball sampling and resulted in responses from 61 gay fathers raising children in 2 states. Fathers reported on the barriers they experienced and the pathways they took to becoming parents. They reported also on experiences of stigma directed at them and their children, especially from family members, friends, and people in religious institutions. Despite these difficulties they reported that they engaged actively in parenting activities and that their child(ren)'s well-being was consistent with national samples.
ERIC Educational Resources Information Center
Tomlinson, Jon C.; Winston, Bruce E.
2011-01-01
This study builds on earlier work by DellaVecchio and Winston (2004) and McPherson (2008). They addressed the seven motivational gifts Paul wrote about in Romans 12:3-8 as a means for addressing job satisfaction and person-job fit among college professors. Using a snowball sampling method, 89 college professors completed the online survey…
ERIC Educational Resources Information Center
McDonald, Barbara
An analytical framework based on Joel Kovel's five meditations on spirit (spirit power, spirit being, spirit meaning, spirit and desire, and divine spirit) was used to explore the spirituality of committed environmental activists. A purposeful and snowball sampling method was used to interview 18 individuals with a strong commitment to…
The Impact of Minority Stress on Mental Health and Substance Use among Sexual Minority Women
ERIC Educational Resources Information Center
Lehavot, Keren; Simoni, Jane M.
2011-01-01
Objective: We examined the direct and indirect impact of minority stress on mental health and substance use among sexual minority women. Method: A combination of snowball and targeted sampling strategies was used to recruit lesbian and bisexual women (N = 1,381) for a cross-sectional, online survey. Participants (M age = 33.54 years; 74% White)…
ERIC Educational Resources Information Center
Hannon, Michael Damon
2013-01-01
This exploratory qualitative dissertation analyzed the narratives of six African-American fathers of children with autism spectrum disorders (ASDs). Contributors were identified via snowball sampling and data were collected using in-depth interviewing and analyzed using analysis of narratives. Findings are presented via individual case…
"Tener Exito": Stories of Self-Efficacy from Undocumented Latinos in the Pursuit of Higher Education
ERIC Educational Resources Information Center
Bailey, Jennifer
2013-01-01
This qualitative study examined the evolvement of self-efficacy and the lived experiences of five undocumented Latino/as during their first semester in a Texas college or university. The snowball sampling method was used to identify participants who were undocumented, immigrated as children and enrolled in K-12 public school, and self-identified…
Why You Can't Have a Snowball Fight on Mars
NASA Astrophysics Data System (ADS)
Sandford, Scott A.
1998-01-01
Icy worlds such as Mars and outer-planet satellites might seem like winter wonderlands, ideal sites for ski slopes, skating rinks, and the crude pleasures of snowball fights. Alas, it was not meant to be.
Simulating the Snowball Stratosphere and Its Influence On CO2 Inference
NASA Astrophysics Data System (ADS)
Graham, R. J.; Shaw, T.; Abbot, D. S.
2017-12-01
According to the snowball Earth hypothesis, a large quantity of CO2 must build up during an event in order to cause eventual deglaciation. One prediction of this model is a depletion in atmospheric oxygen-17 as a result of stratospheric chemical reactions, which has been observed in preserved barite minerals. This represents one of the most dramatic and compelling pieces of evidence in support of the snowball Earth hypothesis. The inference of anomalous atmospheric oxygen-17 based on measurements of barite minerals, however, was made by assuming that the stratosphere-troposphere mass exchange rate and mixing within the stratosphere were the same as the present. In this contribution we test these assumptions with simulations of modern and snowball atmospheric conditions using the global climate model ECHAM5. Our simulations are still running, but we will have results to report by December.
Rapid sea level rise in the aftermath of a Neoproterozoic snowball Earth
NASA Astrophysics Data System (ADS)
Myrow, P. M.; Lamb, M. P.; Ewing, R. C.
2018-05-01
Earth’s most severe climate changes occurred during global-scale “snowball Earth” glaciations, which profoundly altered the planet’s atmosphere, oceans, and biosphere. Extreme rates of glacioeustatic sea level rise are predicted by the snowball Earth hypothesis, but supporting geologic evidence has been lacking. We use paleohydraulic analysis of wave ripples and tidal laminae in the Elatina Formation, Australia—deposited after the Marinoan glaciation ~635 million years ago—to show that water depths of 9 to 16 meters remained nearly constant for ~100 years throughout 27 meters of sediment accumulation. This accumulation rate was too great to have been accommodated by subsidence and instead indicates an extraordinarily rapid rate of sea level rise (0.2 to 0.27 meters per year). Our results substantiate a fundamental prediction of snowball Earth models of rapid deglaciation during the early transition to a supergreenhouse climate.
NASA Astrophysics Data System (ADS)
Warren, S. G.; Dadic, R.; Mullen, P.; Schneebeli, M.; Brandt, R. E.
2012-12-01
The albedos of snow and ice surfaces are, because of their positive feedback, crucial to the initiation, maintenance, and termination of a snowball event, as well as for determining the ice thickness on the ocean. Despite the name, Snowball Earth would not have been entirely snow-covered. As on modern Earth, evaporation would exceed precipitation over much of the tropical ocean. After a transient period with sea ice, the dominant ice type would probably be sea-glaciers flowing in from higher latitude. As they flowed equatorward into the tropical region of net sublimation, their surface snow and subsurface firn would sublimate away, exposing bare glacier ice to the atmosphere and to solar radiation. This ice would be freshwater (meteoric) ice, which originated from snow and firn, so it would contain numerous air bubbles, which determine the albedo. The modern surrogate for this type of ice (glacier ice exposed by sublimation, which has never experienced melting), are the bare-ice surfaces of the Antarctic Ice Sheet near the Trans-Antarctic Mountains. These areas have been well mapped because of their importance in the search for meteorites. A transect across an icefield can sample ice of different ages that has traveled to different depths en route to the sublimation front. On a 6-km transect from snow to ice near the Allan Hills, spectral albedo was measured and 1-m core samples were collected. This short transect is meant to represent a north-south transect across many degrees of latitude on the snowball ocean. Surfaces on the transect transitioned through the sequence: new snow - old snow - firn - young white ice - old blue ice. The transect from snow to ice showed a systematic progression of decreasing albedo at all wavelengths, as well as decreasing specific surface area (SSA; ratio of air-ice interface area to ice mass) and increasing density. The measured spectral albedos are integrated over wavelength and weighted by the spectral solar flux to obtain broadband albedos. These range from 0.8 for snow to 0.55-0.6 for blue ice, which is in the range that favors thick ice over the tropical ocean of Snowball Earth. Air bubbles in the ice, as well as cracks, are responsible for the reflection of sunlight; their contributions to SSA were determined by micro-computed tomography. Scattering by bubbles dominates; removing cracks from the radiative-transfer calculation causes only a slight reduction of albedo. Although what determines the albedo is the SSA of bubbles or snow grains, the broadband albedo also shows a systematic relation to the snow or ice density, suggesting that density might serve as a surrogate variable that will be easier to predict than SSA in an ice-sheet model, using a parameterization for firn densification.
Carbon cycling and snowball Earth.
Goddéris, Yves; Donnadieu, Yannick
2008-12-18
The possibility that Earth witnessed episodes of global glaciation during the latest Precambrian challenges our understanding of the physical processes controlling the Earth's climate. Peltier et al. suggest that a 'hard snowball Earth' state may have been prevented owing to the release of CO(2) from the oxidation of dissolved organic carbon (DOC) in the ocean as the temperature decreased. Here we show that the model of Peltier et al. is not self-consistent as it implies large fluctuations of the ocean alkalinity content without providing any processes to account for it. Our findings suggest that the hard snowball Earth hypothesis is still valid.
Liang, Mao-Chang; Hartman, Hyman; Kopp, Robert E.; Kirschvink, Joseph L.; Yung, Yuk L.
2006-01-01
During Proterozoic time, Earth experienced two intervals with one or more episodes of low-latitude glaciation, which are probable “Snowball Earth” events. Although the severity of the historical glaciations is debated, theoretical “hard Snowball” conditions are associated with the nearly complete shutdown of the hydrological cycle. We show here that, during such long and severe glacial intervals, a weak hydrological cycle coupled with photochemical reactions involving water vapor would give rise to the sustained production of hydrogen peroxide. The photochemical production of hydrogen peroxide has been proposed previously as the primary mechanism for oxidizing the surface of Mars. During a Snowball, hydrogen peroxide could be stored in the ice; it would then be released directly into the ocean and the atmosphere upon melting and could mediate global oxidation events in the aftermath of the Snowball, such as that recorded in the Fe and Mn oxides of the Kalahari Manganese Field, deposited after the Paleoproterozoic low-latitude Makganyene glaciation. Low levels of peroxides and molecular oxygen generated during Archean and earliest Proterozoic non-Snowball glacial intervals could have driven the evolution of oxygen-mediating and -using enzymes and thereby paved the way for the eventual appearance of oxygenic photosynthesis. PMID:17138669
NASA Astrophysics Data System (ADS)
Wang, Z.; Wang, J.; Xiao, S.; Hu, J.
2014-12-01
Environmental changes after the terminal Cryogenian snowball Earth event have been debated extensively in the literature. But there have been relatively few studies on the biotic response in the aftermath of this snowball Earth event. In fact, a variety of potential microbial facies are preserved in basal Ediacaran cap dolostones as peloids, clotted fabrics, and morphologically diverse microbialites (e. g., tube-like stromatolites and stratiform biolaminites). In South China, centimeter-sized domal and conical stromatolites consisting of wavy or wrinkled microbial mats occur at the top of the Doushantuo cap dolostone. Sedimentological investigation of these stromatolites on outcrop and in core samples from the Yangtze Gorges area suggests that they are likely biological in origin. These stromatolites are characterized by vertical accumulation of dark and light laminae. The dark laminae are sub-millimetric in thickness and are composed of probably biogenic kerogen as determined by Raman spectroscopy. The dark laminae is also rich in pyrite, likely derived from organic degradation by sulfate reduction bacteria. Microsparry calcite occur as cements between the dark laminae. Within the Doushantuo stromatolites, there are patches of randomly oriented calcite needles. The precipitation of these calcite needles may have also been facilitated by microbial processes such bacterial sulfate reduction. Our study shows that shallow marine environment became habitable soon after the snowball Earth glaciation ended and benthic microbes were among some of the first organisms to colonize these environments.
ERIC Educational Resources Information Center
Nackoney, Claire Kostopulos
2012-01-01
This phenomenological study explored how HR professionals who identified themselves as facilitators of strategic HRD (SHRD) perceived the experience of being an organizational agent-downsizing survivor. Criterion and snowball sampling were used to recruit 15 participants for this study. A semi-structured interview guide was used to interview…
Temperature dependent mobility measurements of alkali earth ions in superfluid helium
NASA Astrophysics Data System (ADS)
Putlitz, Gisbert Zu; Baumann, I.; Foerste, M.; Jungmann, K.; Riediger, O.; Tabbert, B.; Wiebe, J.; Zühlke, C.
1998-05-01
Mobility measurements of impurity ions in superfluid helium are reported. Alkali earth ions were produced with a laser sputtering technique and were drawn inside the liquid by an electric field. The experiments were carried out in the temperature region from 1.27 up to 1.66 K. The temperature dependence of the mobility of Be^+-ions (measured here for the first time) differs from that of the other alkali earth ions Mg^+, Ca^+, Sr^+ and Ba^+, but behaves similar to that of He^+ (M. Foerste, H. Günther, O. Riediger, J. Wiebe, G. zu Putlitz, Z. Phys. B) 104, 317 (1997). Theories of Atkins (A. Atkins, Phys. Rev.) 116, 1339 (1959) and Cole (M.W. Cole, R.A. Bachmann Phys. Rev. B) 15, 1388 (1977) predict a different defect structure for He^+ and the alkali earth ions: the helium ion is assumed to form a snowball like structure whereas for the alkali earth ions a bubble structure is assumed. If the temperature dependence is a characteristic feature for the different structures, then it seems likely that the Be^+ ion builds a snowball like structure.
A conceptual model of oceanic heat transport in the Snowball Earth scenario
NASA Astrophysics Data System (ADS)
Comeau, Darin; Kurtze, Douglas A.; Restrepo, Juan M.
2016-12-01
Geologic evidence suggests that the Earth may have been completely covered in ice in the distant past, a state known as Snowball Earth. This is still the subject of controversy, and has been the focus of modeling work from low-dimensional models up to state-of-the-art general circulation models. In our present global climate, the ocean plays a large role in redistributing heat from the equatorial regions to high latitudes, and as an important part of the global heat budget, its role in the initiation a Snowball Earth, and the subsequent climate, is of great interest. To better understand the role of oceanic heat transport in the initiation of Snowball Earth, and the resulting global ice covered climate state, the goal of this inquiry is twofold: we wish to propose the least complex model that can capture the Snowball Earth scenario as well as the present-day climate with partial ice cover, and we want to determine the relative importance of oceanic heat transport. To do this, we develop a simple model, incorporating thermohaline dynamics from traditional box ocean models, a radiative balance from energy balance models, and the more contemporary "sea glacier" model to account for viscous flow effects of extremely thick sea ice. The resulting model, consisting of dynamic ocean and ice components, is able to reproduce both Snowball Earth and present-day conditions through reasonable changes in forcing parameters. We find that including or neglecting oceanic heat transport may lead to vastly different global climate states, and also that the parameterization of under-ice heat transfer in the ice-ocean coupling plays a key role in the resulting global climate state, demonstrating the regulatory effect of dynamic ocean heat transport.
NASA Astrophysics Data System (ADS)
Zhan, S.; Chen, Y.; Xu, B.; Wang, B.; Faure, M.
2006-12-01
In order to better constrain the Neoproterozoic paleogeographic reconstruction of continents and improve the understanding of the snowball Earth hypothesis, paleomagnetic collections on Neoproterozoic rocks were carried out in the Aksu area of the northwestern Tarim basin from 2001 to 2005. Six sites of limestone from the Chigebrak formation, 38 sites of sandstone and 4 sites of volcanic rocks from the Sugetbrak formation were sampled. The remaining 24 sites of sandstone and volcanic rocks reveal stable characteristic remanent component (ChRm) isolated from 500 to 680? The computed magnetic directions from these components are relatively consistent and significantly distinguished from those of younger ages. Both normal and reverse polarities have been observed though the normal one is dominant, moreover, the positive fold test is revealed after bedding corrections at 95% confidence level. A paleomagnetic pole is, therefore, calculated: l =19.1? f =149.7? k = 11.2, A95 = 9.3?with n = 24, yielding a paleolatitude of ~27 for the sampling area. The chemostratigraphic correlation of this section with reference ones reveals an average of ~595 Ma for the age for this collection. Comparing paleomagnetic data of the similar ages from Australia and South China as well as other major blocks, the Tarim block seemed being closely located in the north of Australia. A new paleogeographic reconstruction has been attempted which showing a general feature of lower paleolatitude for these blocks. Referring to the paleogeographic reconstruction at about 760Ma proposed by Chen et al. (2004), the continental landmass including the above mentioned blocks seemed having experienced a relatively slow southward kinematic drift and kept their rather low paleolatitude. These observations provide, therefore, evidences to the snowball Earth hypothesis in the late Neoproterozoic time.
Thickness of tropical ice and photosynthesis on a snowball Earth
NASA Technical Reports Server (NTRS)
McKay, C. P.
2000-01-01
On a completely ice-covered "snowball" Earth the thickness of ice in the tropical regions would be limited by the sunlight penetrating into the ice cover and by the latent heat flux generated by freezing at the ice bottom--the freezing rate would balance the sublimation rate from the top of the ice cover. Heat transfer models of the perennially ice-covered Antarctic dry valley lakes applied to the snowball Earth indicate that the tropical ice cover would have a thickness of 10 m or less with a corresponding transmissivity of > 0.1%. This light level is adequate for photosynthesis and could explain the survival of the eukaryotic algae.
Thickness of tropical ice and photosynthesis on a snowball Earth.
McKay, C P
2000-07-15
On a completely ice-covered "snowball" Earth the thickness of ice in the tropical regions would be limited by the sunlight penetrating into the ice cover and by the latent heat flux generated by freezing at the ice bottom--the freezing rate would balance the sublimation rate from the top of the ice cover. Heat transfer models of the perennially ice-covered Antarctic dry valley lakes applied to the snowball Earth indicate that the tropical ice cover would have a thickness of 10 m or less with a corresponding transmissivity of > 0.1%. This light level is adequate for photosynthesis and could explain the survival of the eukaryotic algae.
The Perceived Consequences of Gold Mining in Postwar El Salvador: A Qualitative Study
Cabezas, Pedro; Valle, Evan; Kornfeld, Julie; Muntaner, Carles; Soklaridis, Sophie
2015-01-01
Objectives. We investigated themes related to the health and environmental impacts of gold mining in El Salvador. Methods. Over a 1-month period in 2013, we conducted focus groups (n = 32 participants in total) and individual semistructured interviews (n = 11) with community leaders until we achieved thematic saturation. Data collection took place in 4 departments throughout the country. We used a combination of criterion-purposive and snowballing sampling techniques to identify participants. Results. Multiple themes emerged: (1) the fallacy of economic development; (2) critique of mining activities; (3) the creation of mining-related violence, with parallels to El Salvador's civil war; and (4) solutions and alternatives to mining activity. Solutions involved the creation of cooperative microenterprises for sustainable economic growth, political empowerment within communities, and development of local participatory democracies. Conclusions. Gold mining in El Salvador is perceived as a significant environmental and public health threat. Local solutions may be applicable broadly. PMID:26378845
[Pleasure in nursing technicians working at an emergency unit of a public university hospital].
Garcia, Alessandra Bassalobre; Dellaroza, Mara Solange Gomes; Haddad, Maria do Carmo Lourenço; Pachemshy, Luiza Rita
2012-06-01
This study aimed to reveal the main aspects of the work process and feelings of pleasure experienced by nursing technicians who work at an emergency unit in Paraná, Brazil. The theoretical basis is the psychodynamics of work. This is a qualitative and descriptive study. Data were collected and analyzed using a semi-structured interview and the content analysis technique. Subjects were selected using a snowball sampling. Important aspects of the work process were revealed such as the unpredictability of working in an emergency unit, the impact of team work, and the comprehensive care model as a precursor to humanized care. Pleasure originates from the acknowledgement of their work either by the working subject him/herself by patients or society; and from the team work, realized by the cooperation among professionals. Feelings of pleasure are linked to the acknowledgment of their work, which should be valued since gratification contributes to the psychological health of workers.
The efficacy of respondent-driven sampling for the health assessment of minority populations.
Badowski, Grazyna; Somera, Lilnabeth P; Simsiman, Brayan; Lee, Hye-Ryeon; Cassel, Kevin; Yamanaka, Alisha; Ren, JunHao
2017-10-01
Respondent driven sampling (RDS) is a relatively new network sampling technique typically employed for hard-to-reach populations. Like snowball sampling, initial respondents or "seeds" recruit additional respondents from their network of friends. Under certain assumptions, the method promises to produce a sample independent from the biases that may have been introduced by the non-random choice of "seeds." We conducted a survey on health communication in Guam's general population using the RDS method, the first survey that has utilized this methodology in Guam. It was conducted in hopes of identifying a cost-efficient non-probability sampling strategy that could generate reasonable population estimates for both minority and general populations. RDS data was collected in Guam in 2013 (n=511) and population estimates were compared with 2012 BRFSS data (n=2031) and the 2010 census data. The estimates were calculated using the unweighted RDS sample and the weighted sample using RDS inference methods and compared with known population characteristics. The sample size was reached in 23days, providing evidence that the RDS method is a viable, cost-effective data collection method, which can provide reasonable population estimates. However, the results also suggest that the RDS inference methods used to reduce bias, based on self-reported estimates of network sizes, may not always work. Caution is needed when interpreting RDS study findings. For a more diverse sample, data collection should not be conducted in just one location. Fewer questions about network estimates should be asked, and more careful consideration should be given to the kind of incentives offered to participants. Copyright © 2017. Published by Elsevier Ltd.
ERIC Educational Resources Information Center
Saussaye, Michael G.
2012-01-01
The purpose of this qualitative study was to explore counselor educators' perceptions of working with students unwilling to set aside their personal religious beliefs while counseling clients. Purposeful sampling was used in a snowball fashion to select participants with a minimum of one year experience as a counselor educator and who are…
The lack of selection bias in a snowball sampled case-control study on drug abuse.
Lopes, C S; Rodrigues, L C; Sichieri, R
1996-12-01
Friend controls in matched case-control studies can be a potential source of bias based on the assumption that friends are more likely to share exposure factors. This study evaluates the role of selection bias in a case-control study that used the snowball sampling method based on friendship for the selection of cases and controls. The cases selected fro the study were drug abusers located in the community. Exposure was defined by the presence of at least one psychiatric diagnosis. Psychiatric and drug abuse/dependence diagnoses were made according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R) criteria. Cases and controls were matched on sex, age and friendship. The measurement of selection bias was made through the comparison of the proportion of exposed controls selected by exposed cases (p1) with the proportion of exposed controls selected by unexposed cases (p2). If p1 = p2 then, selection bias should not occur. The observed distribution of the 185 matched pairs having at least one psychiatric disorder showed a p1 value of 0.52 and a p2 value of 0.51, indicating no selection bias in this study. Our findings support the idea that the use of friend controls can produce a valid basis for a case-control study.
Misclassified maternal deaths among East African immigrants in Sweden.
Elebro, Karin; Rööst, Mattias; Moussa, Kontie; Johnsdotter, Sara; Essén, Birgitta
2007-11-01
Western countries have reported an increased risk of maternal mortality among African immigrants. This study aimed to identify cases of maternal mortality among immigrants from the Horn of Africa living in Sweden using snowball sampling, and verify whether they had been classified as maternal deaths in the Cause of Death Registry. Three "locators" contacted immigrants from Somalia, Eritrea, and Ethiopia to identify possible cases of maternal mortality. Suspected deaths were scrutinised through verbal autopsy and medical records. Confirmed instances, linked by country of birth, were compared with Registry statistics. We identified seven possible maternal deaths of which four were confirmed in medical records, yet only one case had been classified as such in the Cause of Death Registry. At least two cases, a significant number, seemed to be misclassified. The challenges of both cultural and medical competence for European midwives and obstetricians caring for non-European immigrant mothers should be given more attention, and the chain of information regarding maternal deaths should be strengthened. We propose a practice similar to the British confidential enquiry into maternal deaths. In Sweden, snowball sampling was valuable for contacting immigrant communities for research on maternal mortality; by strengthening statistical validity, it can contribute to better maternal health policy in a multi-ethnic society.
Public computing options for individuals with cognitive impairments: survey outcomes.
Fox, Lynn Elizabeth; Sohlberg, McKay Moore; Fickas, Stephen; Lemoncello, Rik; Prideaux, Jason
2009-09-01
To examine availability and accessibility of public computing for individuals with cognitive impairment (CI) who reside in the USA. A telephone survey was administered as a semi-structured interview to 145 informants representing seven types of public facilities across three geographically distinct regions using a snowball sampling technique. An Internet search of wireless (Wi-Fi) hotspots supplemented the survey. Survey results showed the availability of public computer terminals and Internet hotspots was greatest in the urban sample, followed by the mid-sized and rural cities. Across seven facility types surveyed, libraries had the highest percentage of access barriers, including complex queue procedures, login and password requirements, and limited technical support. University assistive technology centres and facilities with a restricted user policy, such as brain injury centres, had the lowest incidence of access barriers. Findings suggest optimal outcomes for people with CI will result from a careful match of technology and the user that takes into account potential barriers and opportunities to computing in an individual's preferred public environments. Trends in public computing, including the emergence of widespread Wi-Fi and limited access to terminals that permit auto-launch applications, should guide development of technology designed for use in public computing environments.
Public stigma towards mental illness in the Greek culture.
Tzouvara, V; Papadopoulos, C
2014-12-01
Mental illness stigma negatively affects the lives of individuals with mental health disorders. Studies have indicated that the type and degree of stigma significantly varies across cultures. This study aimed to add to this body of knowledge by examining the prevalence and the type of mental illness stigma among individuals who identified themselves as Greek. It also examined the influence of a range of potential within-culture stigma moderating factors, including levels of previous experience with mental illness and mental illness knowledge. A cross-sectional quantitative design was employed, and 111 participants living in England and Greece were sampled through the snowball sampling technique. Stigma prevalence was measured using the 'Community Attitudes to Mental Illness' questionnaire. The findings revealed that participants showed a high degree of sympathy for people with mental illness but also considered them to be inferior and of a lower social class, and needing strict societal control. Higher stigma was significantly associated with being educated in England (instead of Greece), higher religiosity, lower knowledge levels and lower levels personal experience of mental illness. Targeted antistigma campaigns specifically tailored for the Greek culture are required in order to help reduce stigmatizing attitudes. © 2014 John Wiley & Sons Ltd.
Brazilian immigrants' oral health literacy and participation in oral health care in Canada.
Calvasina, Paola; Lawrence, Herenia P; Hoffman-Goetz, Laurie; Norman, Cameron D
2016-02-15
Inadequate functional health literacy is a common problem in immigrant populations. The aim of this study was to investigate the association between oral (dental) health literacy (OHL) and participation in oral health care among Brazilian immigrants in Toronto, Ontario, Canada. The study used a cross-sectional design and a convenience sample of 101 Brazilian immigrants selected through the snowball sampling technique. Data were analyzed using descriptive statistics and logistic regression modeling. Most of the sample had adequate OHL (83.1 %). Inadequate/marginal OHL was associated with not visiting a dentist in the preceding year (OR = 3.61; p = 0.04), not having a dentist as the primary source of dental information (OR = 5.55; p < 0.01), and not participating in shared dental treatment decision making (OR = 1.06; p = 0.05; OHL as a continuous variable) in multivariate logistic regressions controlling for covariates. A low average annual family income was associated with two indicators of poor participation in oral health care (i.e., not having visited a dentist in the previous year, and not having a dentist as regular source of dental information). Limited OHL was linked to lower participation in the oral health care system and with barriers to using dental services among a sample of Brazilian immigrants. More effective knowledge transfer will be required to help specific groups of immigrants to better navigate the Canadian dental care system.
NASA Astrophysics Data System (ADS)
Kidane, Tesfaye; Bachtadse, Valerian; Alene, Mulugeta
2014-10-01
Eighty-one paleomagnetic cores were collected from 10 locations across a black limestone unit within the core of Negash Synclinorium, northern Ethiopia in order to test the proposed Snowball Earth events for the diamictite unit of the Tambien Group. Cores were cut into two standard paleomagnetic specimens and were subjected to stepwise demagnetizations using both Thermal (TH) and alternating field (AF) techniques. Rock magnetic analyses on representative specimens were done and results revealed goethite, pyrrhotite, titano-magnetite, and titano-hematite to be the major magnetic materials carrying the magnetizations with PSD (pseudo single domain) grain size range. In most cases paleomagnetic directions are defined by a single component of magnetization, where a viscous component is present it is usually removed by heating to a temperature of ∼200 °C or an AF of ∼10 mT. The high stability component isolated above temperature of 200 °C or AF of 15 mT, defined straight line trajectories directed towards the origin and considered as the Characteristic Remanent Magnetization Direction (ChRM). The direction of magnetization of the ChRM is determined for samples with stable straight line segments by the best-fit line using the least square technique of Kirschvink (1980). In the cases of overlapping spectra and unblocking temperatures, direction of magnetization is determined by remagnetization circles of Halls (1976, 1978). When site mean ChRM directions are plotted on stereogram, their distribution is relatively clustered in geographic coordinates and the overall mean direction is Decg = 358.5°, Incg = 16.6° (α95 = 3.8°, K = 162.8, N = 10). After a structural restoration to the horizontal is made the directions disperse and fail the fold test of both McElhinny’s and McFadden’s tests and the mean direction is Decs = 353.5°, Incs = 8.8° (α95 = 18.9°, K = 7.5, N = 10). This is interpreted to result from a later remagnetization of the black limestone. All directions are normal in polarity and have mean unrestored paleomagnetic directions comparable to the Quaternary paleomagnetic directions. Virtual Geomagnetic poles (VGP) in the unrestored position is used to calculate overall mean VGP position resulting long = 235.7°E, latg = 84.5°N (A95 = 3.0°, N = 10). Comparison of the obtained pole with the apparent polar wander path (APWP) curve for Africa of Besse and Courtillot (1991, 2003) and with the 2 Ma reference pole of stable Africa (Kidane et al., 2003) is found to be consistent with remagnetizations during the Quaternary period. Hence supporting evidence for the proposed Snowball Earth event of the Sturtian glaciation in the Negash rocks could not, unfortunately, be obtained from paleomagnetism.
U-shaped curve of psychosis according to cannabis use: New evidence from a snowball sample.
Brañas, Antía; Barrigón, María L; Garrido-Torres, Nathalia; Perona-Garcelán, Salvador; Rodriguez-Testal, Juan F; Lahera, Guillermo; Ruiz-Veguilla, Miguel
2016-12-01
The aim of this study was to investigate the relationship between psychotic-like experiences (PLEs) assessed using the Community Assessment of Psychic Experience (CAPE) questionnaire and the pattern of cannabis use in a non-clinical sample collected by snowball sampling. Our sample was composed of 204 subjects, distributed into three groups by their cannabis use pattern: 68 were non-cannabis users, 40 were moderate cannabis users and 96 were daily cannabis users. We assessed the psychotic experiences in each group with the CAPE questionnaire; and then controlled for the effect of possible confounding factors like sex, age, social exclusion, age of onset of cannabis use, alcohol use and other drug use. We found a significant quadratic association between the frequency of cannabis use and positive (β = -1.8; p = 0.004) and negative dimension scores (β = -1.2; p = 0.04). The first-rank and mania factors showed a significant quadratic association (p < 0.05), while the voices factor showed a trend (p = 0.07). Scores for the different groups tended to maintain a U-shape in their values for the different factors. When we adjusted for gender, age, social exclusion, age of onset of cannabis use, and use of alcohol and other drugs, only the first-rank experiences remained significant. We found there was a U-shaped curve in the association between cannabis use and the positive and negative dimensions of the CAPE score. We also found this association in mania and first-rank experiences. © The Author(s) 2016.
NASA Technical Reports Server (NTRS)
Sohl, L. E.; Chandler, M. A.
2001-01-01
The Neoproterozoic Snowball Earth intervals provide excellent opportunities to examine the environmental limits on terrestrial metazoans. A series of GCM simulations was run in order to quantify climatic conditions during these intervals. Additional information is contained in the original extended abstract.
NASA Technical Reports Server (NTRS)
Kirschvink, J. L.; Gaidos, E. J.; Bertani, L. E.; Beukes, N. J.; Gutzmer, J.; Maepa, L. N.; Steinberger, R. E.
2000-01-01
Geological, geophysical, and geochemical data support a theory that Earth experienced several intervals of intense, global glaciation ("snowball Earth" conditions) during Precambrian time. This snowball model predicts that postglacial, greenhouse-induced warming would lead to the deposition of banded iron formations and cap carbonates. Although global glaciation would have drastically curtailed biological productivity, melting of the oceanic ice would also have induced a cyanobacterial bloom, leading to an oxygen spike in the euphotic zone and to the oxidative precipitation of iron and manganese. A Paleoproterozoic snowball Earth at 2.4 Giga-annum before present (Ga) immediately precedes the Kalahari Manganese Field in southern Africa, suggesting that this rapid and massive change in global climate was responsible for its deposition. As large quantities of O(2) are needed to precipitate this Mn, photosystem II and oxygen radical protection mechanisms must have evolved before 2.4 Ga. This geochemical event may have triggered a compensatory evolutionary branching in the Fe/Mn superoxide dismutase enzyme, providing a Paleoproterozoic calibration point for studies of molecular evolution.
NASA Astrophysics Data System (ADS)
Park, Y.; MacLennan, S. A.; Swanson-Hysell, N.; Maloof, A. C.; Schoene, B.; Alene, M.; Tremblay, M. M.; Anttila, E.; Haileab, B.
2016-12-01
The Snowball Earth hypothesis proposes that the onset of global glaciation was a rapid event, particularly at low-latitudes, due to a runaway ice-albedo instability in the climate system. Currently, the Neoproterozoic Sturtian Snowball Earth Glaciation is constrained to have been ongoing at low-latitudes in present day NW Canada at 716.47 ± 0.24 Ma based on a U-Pb date from a tuff within glacial diamictite (Macdonald et al., 2010). A date from a rhyolite underlying this diamicitite of 717.43 ± 0.14 Ma has been inferred to precede the glaciation, although this age is not a strict maximum for the initiation of the snowball Earth since evidence of glaciation may have been obscured in volcanic units. The Tonian-Cryogenian Tambien Group of northern Ethiopia is a mixed carbonate-siliciclastic sequence deposited in an arc proximal basin that conformably culminates in diamictite associated with the Sturtian Glaciation. This study exploits the presence of tuffs suitable for high precision U-Pb zircon geochronology interbedded with recently discovered exposures of the transition into the snowball Earth. Dates from tuffs stratigraphically <100 m below massive diamictite enable a test of synchronicity for the initiation of the Sturtian Glaciation when compared with data from NW Canada and S China. Furthermore, tuffs in the proximity of the chemostratigraphically defined Islay negative δ13C anomaly give the opportunity to develop new U-Pb dates to test the prediction from Re-Os dating of black shales in NW Canada that the Islay significantly predates the Sturtian ice age, decoupling the sharpest negative downturns in inorganic δ13C values from glacial initiation. These data also augment and temporally constrain the pre-glacial 87Sr/86Sr curve, informing ongoing modeling efforts of global weathering and seawater chemistry as they relate to hypotheses of the role of large igneous province emplacement and paleogeography in the initiation of Snowball Earth glaciation.
Yu, Juping
2009-04-01
Qualitative approaches have been increasingly used to explore ethnic differences in teenage sexual behavior, and methodological issues of conducting such research often remain unaddressed. This article discusses issues related to sampling, rapport, language, and ethnical considerations arising while undertaking research on attitudes toward teenage sexual behavior held by Chinese British families. It highlights the value of using snowball sampling, the importance of establishing rapport, and some advantages of matching the ethnic background between researcher and participants. The researcher's gender and social and cultural backgrounds affect research processes and findings, and this itself merits further reflection.
Interdependent self: self-perceptions of Vietnamese-American youths.
Phan, Tan
2005-01-01
This study examined how Vietnamese-American adolescents perceive themselves in relation to their families. Qualitative, criterion-based sampling and "snowball" or "chain sampling" strategies were used as well as in-depth interviews with 10 Vietnamese-American adolescents. The research focused on parental interactions, family climate, and parental control. The study also looked at peer relationships, parental input, and adolescents' academic achievement orientation. The adolescents described grow closer to, and more emotionally dependent upon, their parents over time. The parents see their children's education as an effective instrument of empowerment and liberation for the entire family, and as providing hope for the future.
Dynamic model constraints on oxygen-17 depletion in atmospheric O2 after a snowball Earth.
Cao, Xiaobin; Bao, Huiming
2013-09-03
A large perturbation in atmospheric CO2 and O2 or bioproductivity will result in a drastic pulse of (17)O change in atmospheric O2, as seen in the Marinoan Oxygen-17 Depletion (MOSD) event in the immediate aftermath of a global deglaciation 635 Mya. The exact nature of the perturbation, however, is debated. Here we constructed a coupled, four-box, and quick-response biosphere-atmosphere model to examine both the steady state and dynamics of the MOSD event. Our model shows that the ultra-high CO2 concentrations proposed by the "snowball' Earth hypothesis produce a typical MOSD duration of less than 10(6) y and a magnitude of (17)O depletion reaching approximately -35‰. Both numbers are in remarkable agreement with geological constraints from South China and Svalbard. Moderate CO2 and low O2 concentration (e.g., 3,200 parts per million by volume and 0.01 bar, respectively) could produce distinct sulfate (17)O depletion only if postglacial marine bioproductivity was impossibly low. Our dynamic model also suggests that a snowball in which the ocean is isolated from the atmosphere by a continuous ice cover may be distinguished from one in which cracks in the ice permit ocean-atmosphere exchange only if partial pressure of atmospheric O2 is larger than 0.02 bar during the snowball period and records of weathering-derived sulfate are available for the very first few tens of thousands of years after the onset of the meltdown. In any case, a snowball Earth is a precondition for the observed MOSD event.
Dirty Snowballs and Magic Carpets: an Ontology of Geophysical Disturbance
NASA Astrophysics Data System (ADS)
Grant, G. E.; Lancaster, S.; O'Connor, J.; Lewis, S.
2002-12-01
Geologists tend to think about landscape-transforming events as "processes" while ecologists tend to view them as "disturbances". In either case, understanding the dynamics of such events is key to interpreting their effects on landforms and ecosystems. Although volcanic eruptions, meteorological and dam break floods, fires, windstorms, and other high-energy events have different origins, internal driving mechanisms, frequencies, and durations, and operate in different types of landscape settings, they share common attributes. Perhaps most importantly, they all represent transformations of energy from one form to another. In some cases the energy of an event generally increases as it propagates through a landscape, primarily through the addition of mass and momentum; examples of these "dirty snowballs" include the initiation and runout phases of volcanic lahars, avalanches, and debris flows. Explosive forest fires can also be viewed as snowballs, in the sense that the heat they generate results in convection that increases their temperatures and rates of movement. In other cases, abstraction of both mass and momentum from a moving body or fluid causes the energy of an event to dissipate with distance, similar to the unwinding of a rug; examples of these "magic carpets" include dam-break floods from a variety of origins, and the depositional phases of lahars and debris flows. Both snowballs and carpets leave distinctive imprints or tracks on the landscape and ecosystems in the form of scour and depositional features, patterns of vegetation disturbance, and rates of subsequent geomorphic or ecosystem recovery. Understanding which processes will snowball and which will unravel is key to determining both their ecosystem impacts and potential risks to humans.
NASA Astrophysics Data System (ADS)
Dobrzinski, Nicole; Bahlburg, Heinrich; Strauss, Harald; Zhang, Qirui
A Neoproterozoic succession of glaciomarine deposits of probably Sturtian age is preserved on the Yangtze Platform in South China. At that time, the South China block was located in intermediate to low paleolatitudes at ca. 40°. The snowball Earth hypothesis offers one possible explanation for the occurrence of low latitude tillites. The hypothesis is largely based on geological and geochemical observation made in deposits underlying or overlying such tillites on several continents. In contrast our study focuses on evidence offered by the tillites themselves. We use major, trace and rare earth geochemistry to evaluate the environmental conditions prevailing during the glaciation. Of particular interest are the intensity of chemical weathering and the relative degree of oxygenation of Neoproterozoic (Nanhuan-Sinian) marine bottom waters. CIA values were obtained from preglacial sand- and siltstones, the matrix of the glacial deposits, fine-grained clastic sediments of a unit intercalated in the glacial succession, and postglacial siltstones and black shales. The data indicate relatively low degrees of chemical weathering for the glacial deposits. In contrast, pre- and postglacial deposits display comparatively elevated levels. This is also true for the intercalated unit, which we interpret as the product of a warmer and more humid interglacial period. Data for S/TOC, U/Th, Cd, Mo, and the Ceanom of the glaciomarine samples indicate the presence of oxic bottom waters during the glaciation. The snowball Earth hypothesis predicts the shutdown of chemical weathering on the continents and complete anoxia of the global ocean largely covered by sea ice for several million years. The geochemical record of the Neoproterozoic tillites on the Yangtze Platform is difficult to reconcile with the snowball Earth hypothesis.
Gonçalves, Janaina R; Nappo, Solange A
2015-07-25
In Brazil, crack cocaine use remains a healthcare challenge due to the rapid onset of its pleasurable effects, its ability to induce craving and addiction, and the fact that it is easily accessible. Delayed action on the part of the Brazilian Government in addressing the drug problem has led users to develop their own strategies for surviving the effects of crack cocaine use, particularly the drug craving and psychosis. In this context, users have sought the benefits of combining crack cocaine with marijuana. Our aim was to identify the reasons why users combine crack cocaine with marijuana and the health implications of doing so. The present study is a qualitative study, using in-depth interviews and criteria-based sampling, following 27 crack cocaine users who combined its use with marijuana. Participants were recruited using the snowball sampling technique, and the point of theoretical saturation was used to define the sample size. Data were analyzed using the content analysis technique. The interviewees reported that the combination of crack cocaine use with marijuana provided "protection" (reduced undesirable effects, improved sleep and appetite, reduced craving for crack cocaine, and allowed the patients to recover some quality of life). Combined use of cannabis as a strategy to reduce the effects of crack exhibited several significant advantages, particularly an improved quality of life, which "protected" users from the violence typical of the crack culture. Crack use is considered a serious public health problem in Brazil, and there are few solution strategies. Within that limited context, the combination of cannabis and crack deserves more thorough clinical investigation to assess its potential use as a strategy to reduce the damage associated with crack use.
Knowledge and practice in mental health nursing care.
Kurimoto, Teresa Cristina da Silva; Penna, Claudia Maria de Mattos; Nitkin, Débora Isane Ratner Kirschbaum
2017-01-01
To understand mental health nursing care based on the concept of the subject of the unconscious proposed by Lacan. A narrative study was carried out with 19 nurses, chosen based on their theoretical approach or referral by other participants, through the snowball sampling technique. The interviews were carried out in person or digitally, and were recorded and fully transcribed. The analysis was carried out based on Freudian and Lacanian psychoanalysis, approaching nursing care as it acts on the body, secretions, and excretions, to distinguish it from the spirit of fineness. Effects on care are discussed, considering the subject of the unconscious with its knowledge, creating unique exits (sinthome). In this situation, professionals are required to abstain from a position of knowing what is better for the Other. This nursing care perspective offers contributions when discussing the centrality of the subject and words in the care process. Compreender o cuidado de enfermagem em saúde mental a partir da concepção de sujeito do inconsciente proposta por Lacan. Pesquisa narrativa, realizada com 19 enfermeiros, determinados por meio de abordagem teórica ou indicação de outro participante, pela técnica de snowball. As entrevistas foram realizadas pessoalmente ou por meio digital, gravadas e transcritas na íntegra. Da análise, fundamentada na psicanálise freudiana e lacaniana, tomou-se o cuidado de enfermagem em seus atos sobre o corpo, suas secreções e excreções, para localizá-lo a partir do espírito de fineza. Discutem-se os efeitos para o cuidado quando se considera o sujeito do inconsciente com seu saber construindo saídas únicas - Sinthoma. Essa condição requer do profissional abster-se de uma posição de saber o que é melhor para o outro. Essa perspectiva de cuidado de enfermagem traz contribuições ao problematizar a centralidade do sujeito e da palavra nas práticas de cuidado.
NASA Astrophysics Data System (ADS)
Voigt, A.
2013-11-01
I study the Hadley circulation of a completely ice-covered Snowball Earth through simulations with a comprehensive atmosphere general circulation model. Because the Snowball Earth atmosphere is an example of a dry atmosphere, these simulations allow me to test to what extent dry theories and idealized models capture the dynamics of realistic dry Hadley circulations. Perpetual off-equatorial as well as seasonally varying insolation is used, extending a previous study for perpetual on-equatorial (equinox) insolation. Vertical diffusion of momentum, representing the momentum transport of dry convection, is fundamental to the momentum budgets of both the winter and summer cells. In the zonal budget, it is the primary process balancing the Coriolis force. In the meridional budget, it mixes meridional momentum between the upper and the lower branch and thereby decelerates the circulation. Because of the latter, the circulation intensifies by a factor of three when vertical diffusion of momentum is suppressed. For seasonally varying insolation, the circulation undergoes rapid transitions from the weak summer into the strong winter regime. Consistent with previous studies in idealized models, these transitions result from a mean-flow feedback, because of which they are insensitive to the treatment of vertical diffusion of momentum. Overall, the results corroborate previous findings for perpetual on-equatorial insolation. They demonstrate that descriptions of realistic dry Hadley circulations, in particular their strength, need to incorporate the vertical momentum transport by dry convection, a process that is neglected in most dry theories and idealized models. An improved estimate of the strength of the Snowball Earth Hadley circulation will also help to better constrain the climate of a possible Neoproterozoic Snowball Earth and its deglaciation threshold.
NASA Astrophysics Data System (ADS)
Voigt, A.
2013-08-01
I study the Hadley circulation of a completely ice-covered Snowball Earth through simulations with a comprehensive atmosphere general circulation model. Because the Snowball Earth atmosphere is an example of a dry atmosphere, these simulations allow me to test to what extent dry theories and idealized models capture the dynamics of dry Hadley circulations. Perpetual off-equatorial as well as seasonally-varying insolation is used, extending a previous study for perpetual on-equatorial (equinox) insolation. Vertical diffusion of momentum, representing the momentum transport of dry convection, is fundamental to the momentum budgets of both the winter and summer cells. In the zonal budget, it is the primary process balancing the Coriolis force. In the meridional budget, it mixes meridional momentum between the upper and the lower branch and thereby decelerates the circulation. Because of the latter, the circulation intensifies by a factor of three when vertical diffusion of momentum is suppressed. For seasonally-varying insolation, the circulation undergoes rapid transitions from the weak summer into the strong winter regime. Consistent with previous studies in idealized models, these transitions result from a mean-flow feedback, because of which they are insensitive to the treatment of vertical diffusion of momentum. Overall, the results corroborate previous findings for perpetual on-equatorial insolation. They demonstrate that an appropriate description of dry Hadley circulations, in particular their strength, needs to incorporate the vertical momentum transport by dry convection, a process that is neglected in most dry theories and idealized models. An improved estimate of the strength of the Snowball Earth Hadley circulation will also help to better constrain the climate of a possible Neoproterozoic Snowball Earth and its deglaciation threshold.
Automatic Evidence Retrieval for Systematic Reviews
Choong, Miew Keen; Galgani, Filippo; Dunn, Adam G
2014-01-01
Background Snowballing involves recursively pursuing relevant references cited in the retrieved literature and adding them to the search results. Snowballing is an alternative approach to discover additional evidence that was not retrieved through conventional search. Snowballing’s effectiveness makes it best practice in systematic reviews despite being time-consuming and tedious. Objective Our goal was to evaluate an automatic method for citation snowballing’s capacity to identify and retrieve the full text and/or abstracts of cited articles. Methods Using 20 review articles that contained 949 citations to journal or conference articles, we manually searched Microsoft Academic Search (MAS) and identified 78.0% (740/949) of the cited articles that were present in the database. We compared the performance of the automatic citation snowballing method against the results of this manual search, measuring precision, recall, and F1 score. Results The automatic method was able to correctly identify 633 (as proportion of included citations: recall=66.7%, F1 score=79.3%; as proportion of citations in MAS: recall=85.5%, F1 score=91.2%) of citations with high precision (97.7%), and retrieved the full text or abstract for 490 (recall=82.9%, precision=92.1%, F1 score=87.3%) of the 633 correctly retrieved citations. Conclusions The proposed method for automatic citation snowballing is accurate and is capable of obtaining the full texts or abstracts for a substantial proportion of the scholarly citations in review articles. By automating the process of citation snowballing, it may be possible to reduce the time and effort of common evidence surveillance tasks such as keeping trial registries up to date and conducting systematic reviews. PMID:25274020
NASA Astrophysics Data System (ADS)
Zakharov, D. O.; Bindeman, I. N.
2015-12-01
The early Paleoproterozoic was an eventful period in the Earth's history. The first portions of free oxygen emerged in the atmosphere, Snowball Earth glaciations happened several times and the first supercontinent broke up due to extensive rifting. These events should have affected the stable isotopic composition of the hydrosphere. In this study, we use rocks that were altered in underwater hydrothermal systems to investigate the stable isotopic composition of the hydrosphere 2.39-2.45 billion years ago (hereinafter, Ga). Extremely low-δ18O (down to -27.5‰ SMOW) rocks from 2.39 Ga metamorphosed subglacial hydrothermal systems of the Belomorian belt, Baltic Shield formed at near-equatorial latitudes suggesting a Snowball (or Slushball) Earth glaciation. These results motivated us to look at temporally and geographically close hydrothermal systems from the unmetamorhposed 2.45 Ga Vetreny Belt rift. The length of the rift is 250 km and it is composed of high-Mg basalts, mafic-ultramafic intrusions and sedimentary successions. We examined several localities of high-Mg basalt flows that include astonishingly fresh pillow lavas, often with preserved volcanic glass, eruptive breccias, and hydrothermal alteration zones. Collected samples serve a great textural evidence of water-rock interaction that occurred in situ while basalts were cooling. The preliminary results from coexisting quartz and epidote (T, D18O=311°C), and from coexisting calcite and quartz (T, D18O=190°C) yield values of δ18O of involved water between -1.6 and -0.9 ‰. The values of δ13C in calcites vary between -4.0 and -2.3 ‰. It is likely that hydrothermal fluids operated in the Vetreny Belt rift were derived from seawater that is no different from modern oceanic water in terms of δ18O. Apparently, the rift was a Paleoproterozoic analog of the modern Red Sea, filled with oceanic water. The result is important because the Vetreny Belt rift predates the onset of Snowball Earth glaciation at 2.4 Ga. The results of our studies can be used as an initial point for meteoric water distillation models of the Paleoproterozoic hydrosphere that was involved in the global Snowball Earth glaciations.
Martin, Donna; Yurkovich, Eleanor; Anderson, Kara
2015-01-01
Objectives The objective was to identify significant family health concerns from the perspective of adult tribal members residing in a reservation setting on the Northern Plains of the United States. Findings were used to co-create culturally appropriate strategies to address the most significant family health concern. Design and Sample A focused ethnography within a participatory framework was employed. An advisory council, comprised of seven tribal members, guided the research team. A purposive sampling technique with a snowball process was used. Twenty-one adult tribal members volunteered to participate. Measures Face-to-face, audio-recorded, semi-structured interviews were conducted and transcribed verbatim. Other data sources included field notes of approximately 100 hours of field work, windshield surveys, and a focus group. Data were analyzed using Spradley’s guidelines. Results The significant family health concern was “diabetes runs rampant here” with inter-related cognitive, emotional and behavioral responses. These responses were compounded by accumulated emotional trauma from witnessing premature deaths and severe comorbidities associated with diabetes. Contextual factors shaping “diabetes runs rampant here” were identified. Conclusion Holistic approaches are urgently needed in diabetes prevention and management programs. Implications for public health nurses are discussed and recommendations are provided for future research. PMID:26336881
Levis, Denise M; Westbrook, Kyresa
2013-01-01
Many health organizations and practitioners in the United States promote preconception health (PCH) to consumers. However, summaries and evaluations of PCH promotional activities are limited. We conducted a content analysis of PCH health education materials collected from local-, state-, national-, and federal-level partners by using an existing database of partners, outreach to maternal and child health organizations, and a snowball sampling technique. Not applicable. Not applicable. Thirty-two materials were included for analysis, based on inclusion/exclusion criteria. A codebook guided coding of materials' characteristics (type, authorship, language, cost), use of marketing and behavioral strategies to reach the target population (target audience, message framing, call to action), and inclusion of PCH subject matter (clinical-behavioral components). The self-assessment of PCH behaviors was the most common material (28%) to appear in the sample. Most materials broadly targeted women, and there was a near-equal distribution in targeting by pregnancy planning status segments (planners and nonplanners). "Practicing PCH benefits the baby's health" was the most common message frame used. Materials contained a wide range of clinical-behavioral components. Strategic targeting of subgroups of consumers is an important but overlooked strategy. More research is needed around PCH components, in terms of packaging and increasing motivation, which could guide use and placement of clinical-behavioral components within promotional materials.
DANA, ALI; MOHAMMADIMEHR, MOJGAN
2017-01-01
Introduction: The main mission of military medicine in the world is to support the health and treatment of the military in relation to issues, risks, injuries and diseases that arise due to the specific occupational conditions. The current study was carried out with the aim of determining the required skills of military physicians to define and determine the required training modules. Methods: The study was a qualitative research. Semi-structured interviews were used to collect the data and qualitative content analysis was used to analyze the data. The study population included all the professors and experts in the field of military medicine and medical sciences at the medical universities of Tehran. Snowball sampling technique was used to sample the study participants. Results: Based on the results, the required skills of military physicians in 5 categories and 29 sub- categories were identified; then based on the identified skills, 60 training modules at two introductory and advanced levels were determined including 39 introductory levels and 21 advanced levels. Conclusion: We can conclude that some of the important skills that military physicians need and can achieved through training have not been provided in any educational program and to achieve such skills and capabilities, other programs should be developed and modular training can be one of them. PMID:28761887
[Nutritional status of street children in the district of Manga (Burkina Faso)].
Diongue, M; Ndiaye, P; Yameogo, I; Faye, B F; Dia, A Tal; Diousse, P
2014-01-01
Malnutrition is an important indicator of development, and its consequences in children and adolescents produce a serious socioeconomic burden. Children living on the street are more vulnerable than others. Thus, our objective was to analyze the nutritional status of children living on the streets of Manga, through a cross-sectional and analytical study. The snowball technique was used for sampling. Data came from individual interviews, blood samples and medical examinations. Of the 237 children studied, 84.8% were boys; the overall mean age was 11.5 years, and 72.6% were adolescents (aged 10 to 17 years). Growth retardation (15.9%) predominated among the children aged 4 to 9 years, while a weight deficit (27.9%) was most common among those aged 10 to 17. Half of the children (50.2%) with blood tests (N = 119) had anemia. There was a link between anemia and underweight (p = 0.0145). Children who ate at least three times a day were 2.63 times less likely to be anemic (p<0.001). Factors associated with anemia (p<0.005) included survival activities. We frequently found nutritional deficits and anemia in these children. A targeted nutritional program would be a good entry point for their successful reintegration..
Domestic Violence: Intersection of Culture, Gender and Context.
Tonsing, Jenny C
2016-04-01
This study examines South Asian women's experience of domestic violence in Hong Kong. Despite the proliferation of literature on domestic violence, this issue remain unexplored in the discourse of domestic violence in Hong Kong. A qualitative research approach through face to face interview with 14 women was employed. Participants were recruited through purposive and snowball sampling. Findings from this study highlight the importance of considering the social and cultural influence on how women perceived and construct their experiences of abuse.Implications for practice and policies are highlighted.
Zainab, Saima; Kadir, Masood
2016-10-01
To determine the prevalence of physical abuse among domestic child labours and to assess the nutritional status by calculating the Body Mass Index of children involved in domestic labour in Karachi. A cross sectional study was conducted in the squatter settlements of Karachi. Questionnaire based interviews were conducted to capture physical abuse with 385 children who worked as domestic labour in the household of their employer. The ages of the children were between 10 to 14 years belonging to both genders. The children were enrolled in study by snow-ball sampling technique. The overall prevalence of physical abuse among domestic child labour in Karachi was found to be 8.3 %. Over 9 % had low weight and about 90% were stunted. This study also highlighted that 95% of the children involved in domestic labour perform overtime work in their employer's home, more than once per week. There is high burden of physical abuse among the domestic child labour and these children are malnourished. There is a need to recognize and regulate this form of labour in Pakistan.
Why not private health insurance? 2. Actuarial principles meet provider dreams
Deber, R; Gildiner, A; Baranek, P
1999-01-01
What do insurers and employers feel about proposals to expand Canadian health care financing through private insurance, in either a parallel stream or a supplementary tier? The authors conducted 10 semistructured, open-ended interviews in the autumn and early winter of 1996 with representatives of the insurance industry and benefits managers working with large employers; respondents were identified using a snowball sampling technique. The respondents felt that proposals for parallel private plans within a competitive market are incompatible with insurance principles, as long as a well-functioning and relatively comprehensive public system continues to exist; the maintenance of a strong public system was both socially and economically desirable. With the exception of serving the niche market for the private management of return-to-work strategies, respondents showed little interest in providing parallel coverage. They were receptive to a larger role for supplementary insurance but cautioned that they are not willing to cover all delisted services. As business executives they stated that they are willing to insure only services and clients that will be profitable. PMID:10497614
Ethnomedical Knowledge of Plants Used for the Treatment of Tuberculosis in Johor, Malaysia
Sabran, Siti Fatimah; Mohamed, Maryati; Abu Bakar, Mohd Fadzelly
2016-01-01
This study documented ethnomedical knowledge of plants used for the treatment of tuberculosis (TB) and its related symptoms as practiced by the Jakun community of Kampung Peta, situated in Endau Rompin Johor National Park, Johor, Malaysia. Eight key informants were selected by snowball sampling technique and data about medicinal plants were collected by semistructured interviews, participatory observations, and focus group. Qualitative analysis was undertaken using thematic analysis. There were 23 species of plants (22 genera, 20 families) documented and herbarium specimens were deposited at the UTHM Herbarium. Dipterocarpus sublamellatus was recorded for the first time with ethnomedical uses while other species were previously reported. The qualitative approach employed in this study demonstrates the emic perspective in terms of perceptions on traditional herbal medicine, transfer of knowledge, significant taboos related with medicinal plants, and their conservation efforts. Local and biomedical terminology in treatment of TB showed substantial correspondence. The outcomes obtained in the study are worth being further investigated for conservation strategies and are worthy of verifying their ethnomedical claims scientifically. PMID:26881002
Santos, Maria O; Almeida, Bianca V DE; Ribeiro, Daiany A; Macêdo, Delmacia G DE; Macêdo, Márcia J F; Macedo, Julimery G F; Sousa, Francisca F S DE; Oliveira, Liana G S DE; Saraiva, Manuele E; Araújo, Thatiane M S; Souza, Marta M A
2017-01-01
Much of the Brazilian semiarid region faces a considerable process of degradation of natural resources, and ethnobotanical studies have collaborated with important information about the use and traditional knowledge, serving as a tool to design conservation strategies of native plant species. Thus, this study aimed to determine medicinal species meriting conservation priorities in a "Caatinga" area in the northeastern of Brazilian territory. The ethnobotanical data were collected through semi-structured interviews with key subjects selected through the "snowball" technique. The availability and species conservation priority was verified by relative density, risk of collection, local use and use of diversity in the forest fragment sampled. It was recorded 42 native medicinal plants and conservation priority score was calculated for seven species, including Mimosa tenuiflora, Hymenaea courbaril, Ximenia americana and Amburana cearensis need immediate conservation and attention, since their collection does not occur in a sustainable way. In order to ensure the perpetuation of the species and the sustainability of traditional therapeutic practice there needs to be a development of conservation practices of caatinga remaining to better conserve the species of the biome.
Yield and turnover of illicit indoor cannabis (Cannabis spp.) plantations in Belgium.
Vanhove, Wouter; Surmont, Tim; Van Damme, Patrick; De Ruyver, Brice
2012-07-10
In prosecution, Belgian judiciary currently uses outdated yield figures (28.1g per plant, sold at € 3/g at grower level) for fining illicit indoor cannabis plantations. Using state-of-the-art cultivation techniques, our growth experiments showed that yield is better expressed in g/m(2) cultivated surface area rather than in g per plant, and that yield varies significantly between different cannabis strains. It was found that the lower-bound of the one-sided 95% confidence interval of the yield of an indoor cannabis plantation can be set at 575 g/m(2). Prices and pricing mechanisms were investigated using interviews with respondents selected through snowball sampling. Results reveal that (i) the Belgian cannabis market chain is highly complex; (ii) unit prices are predominantly determined by transaction sizes; but also (iii) a set of product- and socially-related price-fixing mechanisms have an equally important role. At grower level, respondents reported prices for 1 g of dry cannabis buds to range € 3.00-4.25. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Skinner, Donald; Serekoane, Motsaathebe; Ross, Michael W.
2012-01-01
Background The Diagnostic Interview Schedule for Children (DISC-IV) has been designed for use by trained laypersons. It therefore shows great promise for use in developing countries such as South Africa, where there is a lack of clinically trained and skilled professionals at the primary care level. Against this background, the aim of the current study was to investigate the sociocultural appropriateness of the DISC-IV for use with Sesotho families in South Africa. Methods Qualitative methodology of expert review and contextualized content analyses were used. Ten Sesotho-speaking clinicians were recruited through a snowball sampling technique to the review the DISC through expert review reports. Results Several themes emerged, including the structure of the DISC-IV, its computerized nature, Americanisms, problems in interpretation due to the adversity children live under, language problems, the effect of rural settings and education level, and cultural norms regarding psychiatric symptoms, gender, the experience of time, the expression of emotion, and family structure. Conclusion Recommendations for the sociocultural adaptation and translation of the DISC into Sesotho are made. PMID:20526764
Ocular sarcoidosis: new diagnostic modalities and treatment.
Yang, Sung J; Salek, Sherveen; Rosenbaum, James T
2017-09-01
Ocular involvement in sarcoidosis is present in up to 80% of patients and is frequently manifested before diagnosis of the underlying systemic disease. Considering the therapeutic consequences, early diagnosis of the underlying disease is advantageous in patients presenting with ocular inflammation. There are several ocular findings suggestive of underlying sarcoidosis, such as granulomatous keratic precipitates, iris nodules, cells in the vitreous humor known as snowballs and snowbanks, and retinal periphlebitis. High suspicion is crucial for the diagnosis of sarcoidosis. This review on ocular sarcoidosis will mainly focus on new diagnostic and treatment modalities. Recent studies found possible new diagnostic indicators for the diagnosis of ocular sarcoidosis which include not only serum profiles but also vitreous sample analysis. Ophthalmologic imaging techniques have improved to investigate the ocular structure in detail. Results from recent uveitis clinical trials have included sarcoidosis as an underlying cause and have reported positive results. The diagnosis of ocular sarcoidosis can be challenging in some cases. High suspicion is important to diagnose ocular sarcoidosis with various laboratory and ophthalmic tools. There are many possible options for the treatment of ocular sarcoidosis including various biologic agents.
Developing entrepreneurial competencies for successful business model canvas
NASA Astrophysics Data System (ADS)
Sundah, D. I. E.; Langi, C.; Maramis, D. R. S.; Tawalujan, L. dan
2018-01-01
We explore the competencies of entrepreneurship that contribute to business model canvas. This research conducted at smoked fish industries in Province of North Sulawesi, Indonesia. This research used a mixed method which integrating both quantitative and qualitative approaches in a sequential design. The technique of snowball sampling and questionnaire has been used in collecting data from 44 entrepreneurs. Structural equation modeling with SmartPLS application program has been used in analyzing this data to determine the effect of entrepreneurial competencies on business model canvas. We also investigate 3 entrepreneurs who conducted smoked fish business and analyzed their business by using business model canvas. Focus Group Discussion is used in collecting data from 2 groups of entrepreneurs from 2 different locations. The empirical results show that entrepreneurial competencies which consists of managerial competencies, technical competencies, marketing competencies, financial competencies, human relations competencies, and the specific working attitude of entrepreneur has a positive and significantly effect on business model canvas. Additionally, the empirical cases and discussion with 2 groups of entrepreneurs support the quantitative result and it found that human relations competencies have greater influence in achieving successful business model canvas.
Social Functioning of Kratom (Mitragyna speciosa) Users in Malaysia.
Singh, Darshan; Müller, Christian P; Vicknasingam, Balasingam K; Mansor, Sharif M
2015-01-01
Kratom (Mitragyna speciosa) is an indigenous plant known for its traditional medicinal use, and for its addiction potential, in Southeast Asia. In recent years, kratom and its major alkaloid, mitragynine, spread worldwide with largely unknown effects on behavior and mental health. Recent studies show that kratom use can lead to dependence and that mitragynine works as an addictive drug in animal studies. Nevertheless, kratom preparations were also suggested as a less harmful substitute in opiate withdrawal. Potential side-effects of prolonged kratom use, however, are currently unclear. The aim of this study was to investigate the social functioning of regular kratom users in Malaysia. A cross-sectional survey was carried out in three northern states of Peninsular Malaysia investigating 293 regular kratom consumers using the Addiction Severity Index in a snowball sampling technique. Findings showed that regular kratom users do not experience major impairments in their social functioning, despite being dependent on kratom for prolonged periods. Our findings suggest that chronic kratom administration does not significantly impair social functioning of users in a natural context in Malaysia.
'Self body-management and thinness in youth: survey study on Italian girls'.
Di Giacomo, Dina; De Liso, Giulia; Ranieri, Jessica
2018-06-08
Adherence to the thinness model, self-acceptance such as self-esteem is psychological dynamics influencing the young age and emerging adulthood of women life. The purpose of this study was to investigate the girls and young women' ability to deal with the adherence to thinness model according to their self-body management thought daily self-perception of ownhabits and aptitude. We analysed their emotional patterns and body management to elucidate the Italian phenomenon. A cross-sectional study was conducted on 2287 Italian female distribute in range age 15-25 years old and distributed in girl and young women groups. We conducted a Survey study by snowball sampling technique. Our results showed that girls had higher emotional pattern scores when their weight and shape fit the thinness model: skinny girls felt positively about their body even if when they did not take adequate care of it. Italian girls consider the underweight body mass index an adherence model. Findings suggest the urgent need to plan prevention programme to model healthy behaviours about their daily good practice overcoming social and cultural models based on appearance.
Why not private health insurance? 2. Actuarial principles meet provider dreams.
Deber, R; Gildiner, A; Baranek, P
1999-09-07
What do insurers and employers feel about proposals to expand Canadian health care financing through private insurance, in either a parallel stream or a supplementary tier? The authors conducted 10 semistructured, open-ended interviews in the autumn and early winter of 1996 with representatives of the insurance industry and benefits managers working with large employers; respondents were identified using a snowball sampling technique. The respondents felt that proposals for parallel private plans within a competitive market are incompatible with insurance principles, as long as a well-functioning and relatively comprehensive public system continues to exist; the maintenance of a strong public system was both socially and economically desirable. With the exception of serving the niche market for the private management of return-to-work strategies, respondents showed little interest in providing parallel coverage. They were receptive to a larger role for supplementary insurance but cautioned that they are not willing to cover all delisted services. As business executives they stated that they are willing to insure only services and clients that will be profitable.
ERIC Educational Resources Information Center
Theilheimer, Ish, Ed.; Eisner, Kathy, Ed.
1996-01-01
This issue of the Canadian quarterly "Transitions," in French and English language versions, examines the prevention of youth crime, with a specific focus on activities, trends, and research dealing with Canadian families. Major articles in this issue are: (1) "A Snowball's Chance? Communities and Families Working to Prevent Youth…
Neoproterozoic 'snowball Earth' simulations with a coupled climate/ice-sheet model.
Hyde, W T; Crowley, T J; Baum, S K; Peltier, W R
2000-05-25
Ice sheets may have reached the Equator in the late Proterozoic era (600-800 Myr ago), according to geological and palaeomagnetic studies, possibly resulting in a 'snowball Earth'. But this period was a critical time in the evolution of multicellular animals, posing the question of how early life survived under such environmental stress. Here we present computer simulations of this unusual climate stage with a coupled climate/ice-sheet model. To simulate a snowball Earth, we use only a reduction in the solar constant compared to present-day conditions and we keep atmospheric CO2 concentrations near present levels. We find rapid transitions into and out of full glaciation that are consistent with the geological evidence. When we combine these results with a general circulation model, some of the simulations result in an equatorial belt of open water that may have provided a refugium for multicellular animals.
Sampling challenges in a study examining refugee resettlement
2011-01-01
Background As almost half of all refugees currently under United Nations protection are from Afghanistan or Iraq and significant numbers have already been resettled outside the region of origin, it is likely that future research will examine their resettlement needs. A number of methodological challenges confront researchers working with culturally and linguistically diverse groups; however, few detailed articles are available to inform other studies. The aim of this paper is to outline challenges with sampling and recruitment of socially invisible refugee groups, describing the method adopted for a mixed methods exploratory study assessing mental health, subjective wellbeing and resettlement perspectives of Afghan and Kurdish refugees living in New Zealand and Australia. Sampling strategies used in previous studies with similar refugee groups were considered before determining the approach to recruitment Methods A snowball approach was adopted for the study, with multiple entry points into the communities being used to choose as wide a range of people as possible to provide further contacts and reduce selection bias. Census data was used to assess the representativeness of the sample. Results A sample of 193 former refugee participants was recruited in Christchurch (n = 98) and Perth (n = 95), 47% were of Afghan and 53% Kurdish ethnicity. A good gender balance (males 52%, females 48%) was achieved overall, mainly as a result of the sampling method used. Differences in the demographic composition of groups in each location were observed, especially in relation to the length of time spent in a refugee situation and time since arrival, reflecting variations in national humanitarian quota intakes. Although some measures were problematic, Census data comparison to assess reasonable representativeness of the study sample was generally reassuring. Conclusions Snowball sampling, with multiple initiation points to reduce selection bias, was necessary to locate and identify participants, provide reassurance and break down barriers. Personal contact was critical for both recruitment and data quality, and highlighted the importance of interviewer cultural sensitivity. Cross-national comparative studies, particularly relating to refugee resettlement within different policy environments, also need to take into consideration the differing pre-migration experiences and time since arrival of refugee groups, as these can add additional layers of complexity to study design and interpretation. PMID:21406104
Sampling challenges in a study examining refugee resettlement.
Sulaiman-Hill, Cheryl Mr; Thompson, Sandra C
2011-03-15
As almost half of all refugees currently under United Nations protection are from Afghanistan or Iraq and significant numbers have already been resettled outside the region of origin, it is likely that future research will examine their resettlement needs. A number of methodological challenges confront researchers working with culturally and linguistically diverse groups; however, few detailed articles are available to inform other studies. The aim of this paper is to outline challenges with sampling and recruitment of socially invisible refugee groups, describing the method adopted for a mixed methods exploratory study assessing mental health, subjective wellbeing and resettlement perspectives of Afghan and Kurdish refugees living in New Zealand and Australia. Sampling strategies used in previous studies with similar refugee groups were considered before determining the approach to recruitment A snowball approach was adopted for the study, with multiple entry points into the communities being used to choose as wide a range of people as possible to provide further contacts and reduce selection bias. Census data was used to assess the representativeness of the sample. A sample of 193 former refugee participants was recruited in Christchurch (n = 98) and Perth (n = 95), 47% were of Afghan and 53% Kurdish ethnicity. A good gender balance (males 52%, females 48%) was achieved overall, mainly as a result of the sampling method used. Differences in the demographic composition of groups in each location were observed, especially in relation to the length of time spent in a refugee situation and time since arrival, reflecting variations in national humanitarian quota intakes. Although some measures were problematic, Census data comparison to assess reasonable representativeness of the study sample was generally reassuring. Snowball sampling, with multiple initiation points to reduce selection bias, was necessary to locate and identify participants, provide reassurance and break down barriers. Personal contact was critical for both recruitment and data quality, and highlighted the importance of interviewer cultural sensitivity. Cross-national comparative studies, particularly relating to refugee resettlement within different policy environments, also need to take into consideration the differing pre-migration experiences and time since arrival of refugee groups, as these can add additional layers of complexity to study design and interpretation.
Partnering Patterns and Sexual Behavior Among Korean Men Who Have Sex With Men.
Jung, Minsoo
2016-01-01
This qualitative study investigates the different methods for selecting sex partners by Korean homosexuals considering factors related to homosexual identity and sexual behavior. We take the approach of the grounded theory to examine the issue of sexual partnering of men who have sex with men (MSM). In-depth interviews of urban MSM and bisexual men were conducted. The snowball sampled through a MSM portal web site. Three key informants from the several areas were collected through a MSM portal website, and then, participants were gradually recruited with the snowball samplings in South Korea, 2011 (n=32). The results of coding the interviews based on the grounded theory approach identified three types of partnering: 1) MSM who do not prefer anal intercourse, but pursue safe sex in long-term relationships with fixed partners; 2) those who have fixed partners and perform anal sex, a category into which both MSM and bisexuals fall; and 3) those engaged in anal sex, but enjoy a concurrent sexual relationship without having fixed partners, which was common among bisexuals. The findings from this study elucidate several MSM and bisexual partnering types practice safe sex. This diversity in MSM partnering may increase the vulnerability of some MSM to HIV infection as safe-sex practices remain a matter of individual choice. Changes in Korean societal policies are necessary to enhance capacity building and encourage the practice of safe sex at the community level.
McMahon, Sinead; O'Donoghue, Grainne; Doody, Catherine; O'Neill, Geraldine; Cusack, Tara
2016-05-01
The scope of contemporary physiotherapy practice is a critical factor in determining the appropriate educational preparation for physiotherapists now and into the future. The world-wide shift from secondary to primary healthcare has, and is, continuing to result in new and different ways of working. It is crucial that curricular changes reflect these developments. In this study a qualitative approach using Biggs 3P's - Pressage, Process and Product model to discuss curriculum design. The aim of the study was to explore the perspectives of both national and international physiotherapy educators/practitioners in primary healthcare, on the key elements required in physiotherapy education programmes to prepare future primary healthcare practitioners. Snowball sampling was used to identify experts in education and/or primary healthcare practice. Semi-structured interviews were conducted using an interview guide based on the Biggs 3P's model. Twelve participants were recruited from Ireland (n = 2), the UK (n = 4), Canada (n = 3), New Zealand (n = 2) and Australia (n = 1) using snowball sampling. Interviews were analysed using thematic analysis. Themes identified included; understanding the philosophy of physiotherapy practice, cultural competence, inter-disciplinary team working and communication skills. Contextual factors and teaching and learning strategies were discussed. There is an urgent need for physiotherapy education programmes to adopt the concept of primary healthcare as the basis for the physiotherapy curriculum and illuminate key components for consideration.
NASA Astrophysics Data System (ADS)
Sohl, L.
2014-04-01
The Neoproterozoic "Snowball Earth" glaciations ( 750-635 Ma) have been a special focus for outer habitable zone investigations, owing in large part to a captivating and controversial hypothesis suggesting that Earth may have only narrowly escaped a runaway icehouse state on multiple occasions (a.k.a. "the hard snowball"; Hoffman and Schrag 2001). A review of climate simulations exploring snowball inception (Godderis et al. 2011) reveals that a broad range of models (EBMs, EMICs and AGCMs) tend to yield hard snowball solutions, whereas models with greater 3-D dynamic response capabilities (AOGCMs) typically do not, unless some of their climate feedback responses (e.g., wind-driven ocean circulation, cloud forcings) are disabled (Poulsen and Jacobs 2004). This finding raises the likelihood that models incorporating dynamic climate feedbacks are essential to understanding how much flexibility there may be in the definition of a planet's habitable zone boundaries for a given point in its history. In the first of a series of new Snowball Earth simulations, we use the NASA/GISS ModelE2 Global Climate Model - a 3-D coupled atmosphere/ocean model with dynamic sea ice response - to explore the impacts of wind-driven ocean circulation, clouds and deep ocean circulation on the sea ice front when solar luminosity and atmospheric carbon dioxide are reduced to Neoproterozoic levels (solar = 94%, CO2 = 40 ppmv). The simulation includes a realistic Neoproterozoic land mass distribution, which is concentrated at mid- to tropical latitudes. After 300 years, the sea ice front is established near 30 degrees latitude, and after 600 years it remains stable. As with earlier coupled model simulations we conclude that runaway glacial states would have been difficult to achieve during the Neoproterozoic, and would be more likely to have occurred during earlier times in Earth history when solar luminosity was less. Inclusion of dynamic climate feedback capabilities in habitable zone modeling studies is likely to result in an expansion of our view of what a "Goldilocks" state can entail. Future simulations with a modified version of the NASA/GISS GCM, ROCKE-3D, will take advantage of newly-added model capabilities that evaluate the influence of rotation rate, solar spectral variability, CO2 surface condensation and CO2 clouds on the outer edge of Earth's habitable zone.
Hogan, Teresita M; Olade, Tolulope Oyeyemi; Carpenter, Christopher R
2014-03-01
The aging of America poses a challenge to emergency departments (EDs). Studies show that elderly patients have poor outcomes despite increased testing, prolonged periods of observation, and higher admission rates. In response, emergency medicine (EM) leaders have implemented strategies for improved ED elder care, enhancing expertise, equipment, policies, and protocols. One example is the development of geriatric EDs gaining in popularity nationwide. To the authors' knowledge, this is the first research to systematically identify and qualitatively characterize the existence, locations, and features of geriatric EDs across the United States. The primary objective was to determine the number, distribution, and characteristics of geriatric EDs in the United States in 2013. This was a survey with potential respondents identified via a snowball sampling of known geriatric EDs, EM professional organizations' geriatric interest groups, and a structured search of the Internet using multiple search engines. Sites were contacted by telephone, and those confirming geriatric EDs presence received the survey via e-mail. Category questions included date of opening, location, volumes, staffing, physical plant changes, screening tools, policies, and protocols. Categories were reported based on general interest to those seeking to understand components of a geriatric ED. Thirty-six hospitals confirmed geriatric ED existence and received surveys. Thirty (83%) responded to the survey and confirmed presence or plans for geriatric EDs: 24 (80%) had existing geriatric EDs, and six (20%) were planning to open geriatric EDs by 2014. The majority of geriatric EDs are located in the Midwest (46%) and Northeast (30%) regions of the United States. Eighty percent serve from 5,000 to 20,000 elder patients annually. Seventy percent of geriatric EDs are attached to the main ED, and 66% have from one to 10 geriatric beds. Physical plant changes include modifications to beds (96%), lighting (90%), flooring (83%), visual aids (73%), and sound level (70%). Seventy-seven percent have staff overlapping with the nongeriatric portion of their ED, and 80% require geriatric staff didactics. Sixty-seven percent of geriatric EDs report discharge planning for geriatric ED patients, and 90% of geriatric EDs had direct follow-up through patient callbacks. The snowball sample identification of U.S. geriatric EDs resulted in 30 confirmed respondents. There is significant variation in the components constituting a geriatric ED. The United States should consider external validation of self-identified geriatric EDs to standardize the quality and type of care patients can expect from an institution with an identified geriatric ED. © 2014 by the Society for Academic Emergency Medicine.
Large Igneous Provinces, Sulfur Aerosols, and Initiation of Snowball Earth
NASA Astrophysics Data System (ADS)
Macdonald, F. A.; Wordsworth, R. D.
2015-12-01
The events that led to the initiation of Snowball Earth remain poorly understood. Proposed scenarios include a methane addiction, a biological innovation that led to an increase in organic carbon burial and anaerobic remineralization, or an increase in global weatherability due to a paleogeography with a preponderance of low latitude continents, and the subareal implacement of large igneous provinces (LIPs) at the equator. The Franklin LIP was emplaced between 730 and 710 Ma and covers an area of over 2.25 Mkm2 with lavas, sills, and dikes extending over much of northern Laurentia from Alaska through northern Canada to Greenland and potentially to Siberia. The most precise geochronological constraints on the Franklin LIP overlap with the onset of the Sturtian Snowball Earth glaciation, which began between 717 and 716 Ma and marked the first glaciation in over 1 billion years. The Franklin LIP is the largest preserved Neoproterozoic LIP and one of the largest in Earth History. Additionally, it was emplaced at equatorial latitudes with associated sills that invaded epicontinental sulfur evaporite basins, potentially maximizing environmental effects. Here we explore the hypothesis that the Sturtian Snowball Earth was initiated in part by an increase in planetary albedo from the conversion of volcanic SO2/H2S emissions to tropospheric and stratospheric sulfate aerosols through a combination of geochemical and modeling studies.
A carbon isotope challenge to the snowball Earth.
Sansjofre, P; Ader, M; Trindade, R I F; Elie, M; Lyons, J; Cartigny, P; Nogueira, A C R
2011-10-05
The snowball Earth hypothesis postulates that the planet was entirely covered by ice for millions of years in the Neoproterozoic era, in a self-enhanced glaciation caused by the high albedo of the ice-covered planet. In a hard-snowball picture, the subsequent rapid unfreezing resulted from an ultra-greenhouse event attributed to the buildup of volcanic carbon dioxide (CO(2)) during glaciation. High partial pressures of atmospheric CO(2) (pCO2; from 20,000 to 90,000 p.p.m.v.) in the aftermath of the Marinoan glaciation (∼635 Myr ago) have been inferred from both boron and triple oxygen isotopes. These pCO2 values are 50 to 225 times higher than present-day levels. Here, we re-evaluate these estimates using paired carbon isotopic data for carbonate layers that cap Neoproterozoic glacial deposits and are considered to record post-glacial sea level rise. The new data reported here for Brazilian cap carbonates, together with previous ones for time-equivalent units, provide estimates lower than 3,200 p.p.m.v.--and possibly as low as the current value of ∼400 p.p.m.v. Our new constraint, and our re-interpretation of the boron and triple oxygen isotope data, provide a completely different picture of the late Neoproterozoic environment, with low atmospheric concentrations of carbon dioxide and oxygen that are inconsistent with a hard-snowball Earth.
Street and working children of Delhi, India, misusing toluene: an ethnographic exploration.
Seth, Rajeev; Kotwal, Atul; Ganguly, K K
2005-01-01
Our qualitative study explored: the perceptions of street children indulging in whitener fluid misuse; the social, economic, and cultural determinants of use; and users' views regarding effective preventive and control strategies. Forty-five in-depth interviews and three focus group discussions were conducted between March and December 2003. A purposive sample of those working children who were using toluene was selected by Snowball sampling. The paper discusses the: determinants of initiation and continued use; drug user social networks; psycho emotional deprivation and frustrations of these children; socio-cultural aspects like work driven need; others' attitudinal response towards them and their work; parental support or the lack of it; and strategies for prevention of this misuse.
Roth, Alexis M; Rosenberger, Joshua G; Reece, Michael; Van Der Pol, Barbara
2012-02-01
Transactional sex has been associated with increased risk of adverse health outcomes, including sexually transmitted infections (STIs). Participants included female sex workers and men they recruited utilizing incentivized snowball sampling. Participants provided specimens for STI diagnostic testing and completed a semi-structured interview. Forty-four participants aged 19-65 were interviewed. Participants found self-sampling to be acceptable and overwhelmingly endorsed sampling outside of a clinic (90%) for reasons such as convenience, privacy, and lack of stigma. A substantial minority (38%) tested positive for at least one STI. Novel strategies may encourage sexual health care and prevent STIs among sex workers. High infection and screening acceptance rates across the sample suggests that individuals engaged in transactional sex would benefit from, and would be responsive to, community-based self-sampling for STI screening.
Cryoconite pans on Snowball Earth: supraglacial oases for Cryogenian eukaryotes?
Hoffman, P F
2016-11-01
Geochemical, paleomagnetic, and geochronological data increasingly support the Snowball Earth hypothesis for Cryogenian glaciations. Yet, the fossil record reveals no clear-cut evolutionary bottleneck. Climate models and the modern cryobiosphere offer insights on this paradox. Recent modeling implies that Snowball continents never lacked ice-free areas. Wind-blown dust from these areas plus volcanic ash were trapped by snow on ice sheets and sea ice. At a Snowball onset, sea ice was too thin to flow and ablative ice was too cold for dust retention. After a few millenia, sea ice reached 100 s of meters in thickness and began to flow as a 'sea glacier' toward an equatorial ablation zone. At first, dust advected to the ablative surface was recycled by winds, but as the surface warmed with rising CO 2 , dust aka cryoconite began to accumulate. As a sea glacier has no terminus, cryoconite saturated the surface. It absorbed solar radiation, supported cyanobacterial growth, and sank to an equilibrium depth forming holes and decameter-scale pans of meltwater. As meltwater production rose, drainages developed, connecting pans to moulins, where meltwater was flushed into the subglacial ocean. Flushing cleansed the surface, creating a stabilizing feedback. If the dust flux rose, cryoconite was removed; if the dust flux waned, cryoconite accumulated. In addition to cyanobacteria, modern cryoconite holes are inhabited by green algae, fungi, protists, and certain metazoans. On Snowball Earth, cryoconite pans provided stable interconnected habitats for eukaryotes tolerant of fresh to brackish cold water on an ablation surface 60 million km 2 in area. Flushing and burial of organic matter was a potential source of atmospheric oxygen. Dominance of green algae among Ediacaran eukaryotic primary producers is a possible legacy of Cryogenian cryoconite pans, but a schizohaline ocean-supraglacial freshwater and subglacial brine-may have exerted selective stress on early metazoans, or impeded their evolution. © 2016 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Macouin, M.; Besse, J.; Ader, M.; Gilder, S.; Yang, Z.; Zhiming, S.
2003-04-01
The Neoproterozoic snowball Earth hypothesis is mainly based on the presence of oceanic glacial deposits (dropstones) found at low latitudes. However, a close inspection of the paleomagnetic literature shows that only a single datum from Australia satisfies minimum quality criteria. We thus carried out a paleomagnetic and isotopic study of 185 cores from 10 sites in the Nantuo tillite and overlying Doushantuo carbonates formations in Hunan Province, South China block. The Doushantuo carbonates have been recently radiometrically dated at 600 Ma, which correlates in time with the Marinoan (or Varangian) glaciation event. The tillite is remagnetized, carrying either the present Earth's field direction or a well known Mesozoic remagnetization direction. However, only some of the Doushantuo carbonates were remagnetized, and a high temperature component carried by magnetite could be isolated in 50% of the samples. The directions associated with this component pass the fold test at the 95% confidence level and yield a mean pole at 0.6^oN and 197^oE (Dp=4.5^o, Dm=9^o), which implies that the carbonates were deposited at equatorial latitudes. Potential questions concerning the primary nature of the magnetic remanence will be discussed. Variations of δ13C from calcite and dolomite fractions from the base of the Doushantuo Formation show depleted values of around 5 ppm associated with the cap carbonates just above the tillite and probably reflect the deglaciation process. They progressively attain positive values of nearly +5 ppm, as already described in other equivalent Chinese sections, switching again at the summit toward highly negative values (-20 ppm) for the calcite. These highly negative values suggest a methane-derived origin. Interestingly, they are associated in our section with a loss of remanent magnetization intensity, which probably results from the dissolution of magnetite by H_2S produced by the oxidation of methane. Paleomagnetic and isotopic implications of our study on the snowball Earth hypothesis will be discussed.
NASA Astrophysics Data System (ADS)
Gregory, L. C.; Meert, J. G.; Levashova, N.; Grice, W. C.; Gibsher, A.; Rybanin, A.
2007-12-01
The Neoproterozoic to early Paleozoic Ural-Mongol belt that runs through Central Asia is crucial for determining the enigmatic amalgamation of microcontinents that make up the Eurasian subcontinent. Two unique models have been proposed for the evolution of Ural-Mongol belt. One involves a complex assemblage of cratonic blocks that have collided and rifted apart during diachronous opening and closing of Neoproterozoic to Devonian aged ocean basins. The opposing model of Sengor and Natal"in proposes a long-standing volcanic arc system that connected Central Asian blocks with the Baltica continent. The Aktau-Mointy and Dzabkhan microcontinents in Kazakhstan and Central Mongolia make up the central section of the Ural-Mongol belt, and both contain glacial sequences characteristic of the hypothesized snowball earth event. These worldwide glaciations are currently under considerable debate, and paleomagnetic data from these microcontients are a useful contribution to the snowball controversy. We have sampled volcanic and sedimentary sequences in Central Mongolia, Kazakhstan and Kyrgyzstan for paleomagnetic and geochronologic study. U-Pb data, 13C curves and abundant fossil records place age constraints on sequences that contain glacial deposits of the hypothesized snowball earth events. Carbonates in the Zavkhan Basin in Mongolia are likely remagnetized, but fossil evidence within the sequence suggests a readjusted age control on two glacial events that were previously labeled as Sturtian and Marinoan. U-Pb ages from both Kazakhstan and Mongolian volcanic sequences imply a similar evolution history of the areas as part of the Ural-Mongol fold belt, and these ages paired with paleomagnetic and 13C records have important tectonic implications. We will present these data in order to place better constraints on the Precambrian to early Paleozoic tectonic evolution of Central Asia and the timing of glacial events recorded in the area.
The importance of self-management in the prevention and treatment of excessive weight and obesity.
Tóthová, Valérie; Bártlová, Sylva; Šedová, Lenka; Olišarová, Věra; Prokešová, Radka; Adámkova, Věra; Mauritzová, Ilona; Trešlová, Marie; Chloubová, Ivana; Mikšová, Zdeňka
2015-01-01
The aim of this research into 'self-management' was to determine to what extent respondents were aware of their status as overweight or obese. For respondents who indicated that they were overweight or obese, the goal was to determine whether they tried to lose weight, what steps they took to control their, and what specific methods they used. Information was collected using semi-structured interviews from May 31, 2014, to January 30, 2015. Data processing was performed using statistical analysis of the social data SASDM 01/04/10 software. The total study group consisted of 600 respondents, including 302 from the Roma minority, and 298 from the non-Roma majority population (control group). Respondents were selected specifically from South Bohemia Region of the Czech Republic. The sample from the Roma minority was constructed using the snowball method (Snowball Sampling). The control sample of non-Roma was selected through quota sampling. The results indicate that the respondents from both the Roma minority and the non-Roma control group generally recognized when they were overweight or obese, or they were aware of it to a much lesser extent than objective indicators revealed. More than two thirds of the respondents who admitted they were overweight or obese (N = 143) reported that they had suffered from overweight or obesity since they were young adults. Significantly more members of the majority population had tried to lose weight using self-management, whereas the level of effort was significantly less among members of the Roma minority (P = 0). Nevertheless, Roma respondents significantly more often reported (P < 0.01) that they had agreed on a specific weight loss plan with a doctor. The results of our research show that in the context of prevention, it is important to promote self-managed skills, habits and other characteristics that can play an important role in the prevention and treatment of obesity and overweight.
Korf, Dirk J; van Ginkel, Patrick; Benschop, Annemieke
2010-05-01
The first aim is to better understand the potentials and limitations of different sampling methods for reaching a specific, rarely studied population of drug users and for persuading them to take part in a multidisciplinary study. The second is to determine the extent to which these different methods reach similar or dissimilar segments of the non-dependent opiate-using population. Using ethnographic fieldwork (EFW) and targeted canvassing (TARC; small newspaper advertisements and website announcements), supplemented by snowball referrals, we recruited and interviewed 127 non-dependent opiate users (lifetime prevalence of use 5-100 times; 86.6% had used heroin and 56.7% opium). Average age was 39.0; 66.1% were male and 33.9% female. In addition to opiates, many respondents had wide experience with other illicit drugs. The majority had non-conventional lifestyles. Both EFW and TARC yielded only limited numbers of snowball referrals. EFW requires specific skills, is labour-intensive, thus expensive, but allows unsuitable candidates to be excluded faster. Respondents recruited through EFW were significantly more likely to have experience with opium and various drugs other than opiates. TARC resulted in larger percentages of women and respondents with conventional lifestyles. TARC is less labour-intensive but requires more time for screening candidates; its cost-effectiveness depends on the price of advertising for the recruitment. Different methods reach different segments of the population of non-dependent opiate users. It is useful to employ a multi-method approach to reduce selectivity. Copyright 2009 Elsevier B.V. All rights reserved.
Rolls, David A.; Wang, Peng; McBryde, Emma; Pattison, Philippa; Robins, Garry
2015-01-01
We compare two broad types of empirically grounded random network models in terms of their abilities to capture both network features and simulated Susceptible-Infected-Recovered (SIR) epidemic dynamics. The types of network models are exponential random graph models (ERGMs) and extensions of the configuration model. We use three kinds of empirical contact networks, chosen to provide both variety and realistic patterns of human contact: a highly clustered network, a bipartite network and a snowball sampled network of a “hidden population”. In the case of the snowball sampled network we present a novel method for fitting an edge-triangle model. In our results, ERGMs consistently capture clustering as well or better than configuration-type models, but the latter models better capture the node degree distribution. Despite the additional computational requirements to fit ERGMs to empirical networks, the use of ERGMs provides only a slight improvement in the ability of the models to recreate epidemic features of the empirical network in simulated SIR epidemics. Generally, SIR epidemic results from using configuration-type models fall between those from a random network model (i.e., an Erdős-Rényi model) and an ERGM. The addition of subgraphs of size four to edge-triangle type models does improve agreement with the empirical network for smaller densities in clustered networks. Additional subgraphs do not make a noticeable difference in our example, although we would expect the ability to model cliques to be helpful for contact networks exhibiting household structure. PMID:26555701
Coffee shops and clinics: the give and take of doing HIV/AIDS research with injecting drug users.
Marsh, A; Loxley, W
1992-06-01
We discuss recruiting and interviewing injecting drug users and using research as health promotion in the context of collecting information related to human immunodeficiency virus (HIV) or acquired immune deficiency syndrome (AIDS) from a convenience sample of 200 injecting drug users, half in treatment and half not, in 1989 and 1990 in Perth, Western Australia. A variety of recruiting methods were used including advertising, referral by agency staff, 'snowballing' and approaches to personal contacts and others known to inject by the interviewer. Snowballing and personal contacts were the most successful means of recruiting those not in treatment, while advertising was comparatively unsuccessful with this group because of the importance of establishing the credibility of the study and the interviewer among injecting drug users before they will volunteer to be involved. The promotion of behavioural risk reduction among respondents during the interview is detailed. We argue that the traditionally rigid separation between research and intervention is inappropriate in the HIV/AIDS context. When lives are potentially at stake, any contact with injecting drug users, especially those not in treatment (where may receive HIV/AIDS education), must be used as an HIV/AIDS prevention opportunity, and the interview is an ideal opportunity. The employment of research as community intervention is also discussed.
Cordia dichotoma G. Forst. : Bioecology and population density
NASA Astrophysics Data System (ADS)
Rahayu, E. S.; Martin, P.; Dewi, N. K.; Kurniawan, F. H.
2017-04-01
Kendal tree is declared as an identity flora of Kendal Regency, Central Java, Indonesia. It is predicted as a rare species; most of the local people do not know the existence of this tree. The study aimed to describe some aspects of bioecology and a population density of Kendal tree. An explorative study was conducted from March to July 2016, through interview, observation, and literature review. The respondents were determined by purposive and snowball sampling methods. The data were analysed descriptively. Results showed that there were very limited numbers (only five trees) of Kendal tree throughout Kendal Regency. The species was identified as Cordia dichotoma G. Forst. The tree is 3-15 m in height. The leaves are simple and arranged spirally, inflorescence dichotomous, bisexual, with five gamosepalous and gamopetalous. Generative reproduction occurred at a low rate. The tree grew optimally in a dusty, sandy loam soil, pH 6.0-6.5 with a temperature ranged from 27-34 °C, a light intensity of 450-1580 lux, and an altitude of about 10 meters above sea level. In conclusion, C. dichotoma is a rare plant in Kendal Regency. This plant needs an alternative method of propagation, regeneration and conservation using in vitro technique.
[Perceptions of adolescents Jalisco campaign on breast cancer].
Tapia-Curiel, Amparo; Nuño-Gutiérrez, Bertha Lidia; Flores-Padilla, Luis; Villaseñor-Farías, Martha; López-López, José Luis; Covarrubias-Bermúdez, María de los Ángeles
2015-01-01
Breast cancer campaigns and awareness strategies with limited evidence of their effectiveness in youth. Behavioral model of perception that shows how individuals choose, organize and interpret information. This study shows the perceptions of youth from Jalisco regarding breast cancer campaigns. Cross-sectional qualitative exploratory study based on constructionist and associationist theories of perception. Informed consent interviews with 13 focus groups, 129 men and women between 12 and 19 years old, enrolled students, residents of 6 regions of Jalisco. The sampling consisted in snowball technique. Interviews transcribed and processed with Atlas Ti version 4.1, open coding analysis. 10 campaigns were identified and the perceptions about them showed 3 processes: 1) SELECTION: permeated by the campaign design elements; 2) ORGANIZATION: influenced by pre-structured meanings of the color pink, scope and limitations of the campaigns; and 3) INTERPRETATION: showed judgments about the visibility of breast cancer, accessibility of knowledge and resources, permeability of positive ads and cultural codes and the lack of coverage meeting expectations. A high awareness of breast cancer among teenagers was evident as well as the extensive need of information and services. We recommend creating strategies for formal education about breast cancer during adolescence.
Barrientos-Delgado, Jaime; Cárdenas-Castro, Manuel; Gómez-Ojeda, Fabiola
2014-06-01
This article describes the socio-demographic characteristics of a sample of gay men in three cities in Chile, as well as experience with homophobia and subjective well-being. Snowball sampling was used to interview 325 gay men. The main findings included high levels of perceived discrimination and victimization, but interviewees reported higher levels of social well-being compared to studies elsewhere in the country. Age was related to differences in levels of social well-being, but not other variables. Individuals with university education reported higher levels of victimization and greater impact of discrimination on their lives. Gay men in Santiago reported a higher relative impact from incidents of aggression, but better levels of social well-being and happiness compared to those in other regions of Chile.
Tucker, Jalie A; Simpson, Cathy A; Chandler, Susan D; Borch, Casey A; Davies, Susan L; Kerbawy, Shatomi J; Lewis, Terri H; Crawford, M Scott; Cheong, JeeWon; Michael, Max
2016-01-01
Emerging adulthood often entails heightened risk-taking with potential life-long consequences, and research on risk behaviors is needed to guide prevention programming, particularly in under-served and difficult to reach populations. This study evaluated the utility of Respondent Driven Sampling (RDS), a peer-driven methodology that corrects limitations of snowball sampling, to reach at-risk African American emerging adults from disadvantaged urban communities. Initial "seed" participants from the target group recruited peers, who then recruited their peers in an iterative process (110 males, 234 females; M age = 18.86 years). Structured field interviews assessed common health risk factors, including substance use, overweight/obesity, and sexual behaviors. Established gender-and age-related associations with risk factors were replicated, and sample risk profiles and prevalence estimates compared favorably with matched samples from representative U.S. national surveys. Findings supported the use of RDS as a sampling method and grassroots platform for research and prevention with community-dwelling risk groups.
HST WFC3/IR Calibration Updates
NASA Astrophysics Data System (ADS)
Durbin, Meredith; Brammer, Gabriel; Long, Knox S.; Pirzkal, Norbert; Ryan, Russell E.; McCullough, Peter R.; Baggett, Sylvia M.; Gosmeyer, Catherine; Bourque, Matthew; HST WFC3 Team
2016-01-01
We report on several improvements to the characterization, monitoring, and calibration of the HST WFC3/IR detector. The detector performance has remained overall stable since its installation during HST Servicing Mission 4 in 2009. We present an updated persistence model that takes into account effects of exposure time and spatial variations in persistence across the detector, new grism wavelength solutions and master sky images, and a new SPARS sample sequence. We also discuss the stability of the IR gain, the time evolution and photometric properties of IR "snowballs," and the effect of IR "blobs" on point-source photometry.
Yarmohammadian, Mohammad Hossein; Atighechian, Golrokh; Shams, Lida; Haghshenas, Abbas
2011-08-01
Applying an effective management system in emergency incidents provides maximum efficiency with using minimum facilities and human resources. Hospital Emergency Incident Command System (HEICS) is one of the most reliable emergency incident command systems to make hospitals more efficient and to increase patient safety. This research was to study requirements, barriers, and strategies of HEICS in hospitals affiliated to Isfahan University of Medical Sciences (IUMS). This was a qualitative research carried out in Isfahan Province, Iran during 2008-09. The study population included senior hospital managers of IUMS and key informants in emergency incident management across Isfahan Province. Sampling method was in non-random purposeful form and snowball technique was used. The research instrument for data collection was semi-structured interview; collected data was analyzed by Colaizzi Technique. Findings of study were categorized into three general categories including requirements (organizational and sub-organizational), barriers (internal and external) of HEICS establishment, and providing short, mid and long term strategies. These categories are explained in details in the main text. Regarding the existing barriers in establishment of HEICS, it is recommended that responsible authorities in different levels of health care system prepare necessary conditions for implementing such system as soon as possible via encouraging and supporting systems. This paper may help health policy makers to get reasonable framework and have comprehensive view for establishing HEICS in hospitals. It is necessary to consider requirements and viewpoints of stakeholders before any health policy making or planning.
Constraints on Nubular Electromagnetic Pulses
NASA Astrophysics Data System (ADS)
Eisenhour, D. D.; Buseck, P. R.
1993-07-01
Chondritic meteorites contain an abundance of silicate minerals with opaque inclusions of oxides, sulfides, and metals. These host silicates interact differently from their enclosed opaques to electromagnetic (EM) radiation; specifically, silicates are inefficient at absorbing EM energy in the visible and near infrared while metals, sulfides, and Fe oxides absorb strongly in this frequency range. In the presence of a strong electromagnetic pulse (EMP), this preferential absorption leads to the selective heating of the opaque inclusions and can produce unique textures ("dirty snowballs": intimate, ~spherical intergrowths of silicate and opaque minerals with radii of < 1 to 10 micrometers) that record the passage of the EMP. Many chondrules, CAIs, and isolated silicate grains within chondritic meteorites exhibit these unique features, suggesting that strong EMPs were common in the early solar nebula [1]. Here we discuss new constraints on nebular EMPs obtained from both experimental simulations and calculations of radiative heat transport. To test the feasibility of producing "dirty snowball" textures by EMP heating, olivines and pyroxenes containing metal and sulfide inclusions were heated with a 10 watt, argon-ion, CW laser operated at 514 nm. Comparisons between meteoritic "dirty snowball" textures and experimentally produced textures confirm the ability to produce the meteoritic textures by EMP heating and suggest heating times and fluxes of 0.25 to 10 seconds and 10^9 to 10^10 ergs cm^-2 sec^-1. Fluxes less than 10^9 ergs cm^-2 sec^-1 were insufficient to melt metal and sulfide inclusions, while fluxes greater than 10^10 ergs cm^-2 sec^-1 resulted in complete melting of metal, sulfide, and silicates. The experimentally determined heating time scales suggest that radiative equilibrium was reached in the "dirty snowball" formation process, indicating that the range of observed textures is controlled by cooling rates. Calculations of radiative absorption and emission allow further constraints to be placed on the EMPs responsible for "dirty snowball" formation. The absorption and emission efficiencies of grains in a blackbody radiation field were determined by calculating Planck mean cross sections for olivine, pyroxene, and iron as a function of grain size [2,3]. This information was combined with conductive heat flow calculations to determine the behavior of olivine and pyroxene grains with small inclusions of metal. Results indicate that "dirty snowball" formation results only over a narrow flux range for a given multiphase assemblage, with higher fluxes required for smaller, more transparent, or more refractory grains. For a 100-mm olivine chondrule containing a 10-micrometer "dirty snowball," the required flux is ~9 +- 1 x 10^8 ergs cm^-2 sec^-1, with a minimum pulse duration of 4 seconds (assuming an initial grain temperature of 500 K prior to heating). These values are in good agreement with experimentally determined values. The results show that pulses energetic enough to create "dirty snowballs" are also capable of producing the total melting required for chondrule formation with only slight increases in flux, or with only marginally different grain properties (e.g., more opaque inclusions, lower melting points, higher absorption cross sections). Because of the temperature and grain size dependence of the Planck mean cross sections of silicates, an EMP of the type described above will selectively melt larger aggregates and individual grains (>100 micrometer) while leaving smaller aggregates and grains unmelted. Therefore, natural products of EMP heating are: 1) the formation of chondrules in a sustained dusty environment, 2) a paucity of small chondrules, and 3) residual grains relatively unaffected by the EMPs. References: [1] Eisenhour D. D. and Buseck P. R. (1993) LPSC XXIV, 435-436. [2] Falk S. W. and Scalo J. M. (1975) Ap. J., 202, 690-695. [3] Gilman R. C. (1974) Ap. J. Supp., 268, 28, 397-403.
McCreesh, Nicky; Tarsh, Matilda Nadagire; Seeley, Janet; Katongole, Joseph; White, Richard G
2013-01-01
Respondent-driven sampling (RDS) is a widely-used variant of snowball sampling. Respondents are selected not from a sampling frame, but from a social network of existing members of the sample. Incentives are provided for participation and for the recruitment of others. Ethical and methodological criticisms have been raised about RDS. Our purpose was to evaluate whether these criticisms were justified. In this study RDS was used to recruit male household heads in rural Uganda. We investigated community members' understanding and experience of the method, and explored how these may have affected the quality of the RDS survey data. Our findings suggest that because participants recruit participants, the use of RDS in medical research may result in increased difficulties in gaining informed consent, and data collected using RDS may be particularly susceptible to bias due to differences in the understanding of key concepts between researchers and members of the community.
GCM simulations of cold dry Snowball Earth atmospheres
NASA Astrophysics Data System (ADS)
Voigt, A.; Held, I.; Marotzke, J.
2009-12-01
We use the full-physics atmospheric general circulation model ECHAM5 to investigate cold and virtually dry Snowball Earth atmospheres. These result from specifying sea ice as the surface boundary condition everywhere, corresponding to a frozen aquaplanet, while keeping total solar irradiance at its present-day value of 1365 Wm-2 and setting atmospheric carbon dioxide to 300 ppmv. Here, we present four simulations corresponding to the four possible combinations of enabled or disabled diurnal and seasonal cycles. The aim of this study is twofold. First, we focus on the zonal-mean circulation of Snowball Earth atmospheres, which, due to missing moisture, might constitute an ideal though yet unexplored testbed for theories of atmospheric dynamics. Second, we investigate tropical surface temperatures with an emphasis on the impact of the diurnal and seasonal cycles. This will indicate whether the presence of the diurnal or seasonal cycle would facilitate or anticipate the escape from Snowball Earth conditions when total solar irradiance or atmospheric CO2 levels were increased. The dynamics of the tropical circulation in Snowball Earth atmospheres differs substantially from that in the modern atmosphere. The analysis of the mean zonal momentum budget reveals that the mean flow meridional advection of absolute vorticity is primarily balanced by vertical diffusion of zonal momentum. The contribution of eddies is found to be even smaller than the contribution of mean flow vertical advection of zonal momentum, the latter being usually neglected in theories for the Hadley circulation, at least in its upper tropospheric branch. Suppressing vertical diffusion of horizontal momentum above 850 hPa leads to a stronger Hadley circulation. This behaviour cannot be understood from axisymmetric models of the atmosphere, nor idealized atmospheric general circulation models, which both predict a weakening of the Hadley circulation when the vertical viscosity is decreased globally. We find that enabling the diurnal cycle does not change tropical annual-mean surface temperatures but significantly strengthens the Hadley circulation, which increases by 33% for equinoctial and by 50% during solstitial insolation conditions compared to simulations without diurnal cycle. Including the seasonal cycle results in a ''reversed'' annual-mean Hadley circulation with subsiding motion at the equator and ascending motion around 15N/S, a manifestation of the extreme seasonality of Snowball Earth atmospheres due to the low thermal inertia of the sea-ice surface. The impact of the seasonal cycle on the tropical annual-mean surface is a straightforward consequence of changes in insolation distribution: as annual-mean incoming shortwave radiation at the equator reduces by 18 Wm-2 for enabled seasonal cycle, tropical annual-mean surface temperatures decrease from 221 K to 217 K.
Review of sampling hard-to-reach and hidden populations for HIV surveillance.
Magnani, Robert; Sabin, Keith; Saidel, Tobi; Heckathorn, Douglas
2005-05-01
Adequate surveillance of hard-to-reach and 'hidden' subpopulations is crucial to containing the HIV epidemic in low prevalence settings and in slowing the rate of transmission in high prevalence settings. For a variety of reasons, however, conventional facility and survey-based surveillance data collection strategies are ineffective for a number of key subpopulations, particularly those whose behaviors are illegal or illicit. This paper critically reviews alternative sampling strategies for undertaking behavioral or biological surveillance surveys of such groups. Non-probability sampling approaches such as facility-based sentinel surveillance and snowball sampling are the simplest to carry out, but are subject to a high risk of sampling/selection bias. Most of the probability sampling methods considered are limited in that they are adequate only under certain circumstances and for some groups. One relatively new method, respondent-driven sampling, an adaptation of chain-referral sampling, appears to be the most promising for general applications. However, as its applicability to HIV surveillance in resource-poor settings has yet to be established, further field trials are needed before a firm conclusion can be reached.
Toward cost-efficient sampling methods
NASA Astrophysics Data System (ADS)
Luo, Peng; Li, Yongli; Wu, Chong; Zhang, Guijie
2015-09-01
The sampling method has been paid much attention in the field of complex network in general and statistical physics in particular. This paper proposes two new sampling methods based on the idea that a small part of vertices with high node degree could possess the most structure information of a complex network. The two proposed sampling methods are efficient in sampling high degree nodes so that they would be useful even if the sampling rate is low, which means cost-efficient. The first new sampling method is developed on the basis of the widely used stratified random sampling (SRS) method and the second one improves the famous snowball sampling (SBS) method. In order to demonstrate the validity and accuracy of two new sampling methods, we compare them with the existing sampling methods in three commonly used simulation networks that are scale-free network, random network, small-world network, and also in two real networks. The experimental results illustrate that the two proposed sampling methods perform much better than the existing sampling methods in terms of achieving the true network structure characteristics reflected by clustering coefficient, Bonacich centrality and average path length, especially when the sampling rate is low.
He, Shanshan; Tsang, Sandra
2014-01-01
Attachment theory has great potential to help our understanding of the apparent contradiction between violence and intimacy. Yet very few studies applied this theory to explain or predict sexual coercion in the context of intimate relationships. This study examined the relation between male partners' attachment styles and women's coerced first sexual intercourse in dating relationships. There were 927 valid questionnaires collected by purposive snowball sampling in five main cities in China to college students who were currently in a romantic relationship. Results showed that in both male and female samples, male partners' anxious attachment style were significantly and positively predicted emotional manipulation coercive tactics. In the female sample, male partners' two attachment styles (anxious and avoidant) positively predicted violence threat tactics, and male partners' avoidant attachment style positively predicted defection threat tactics. The research hypothesis of this study has been successfully supported, and implications and limitations were discussed.
Mohammadi, N; Jones, T; Evans, D
2008-12-01
Participant recruitment is a fundamental component of the research process and the methods employed to attract individuals will depend on the nature of the study. Recruitment may be more challenging when the study involves people from a minority religious group. However, this issue has not been well addressed in the literature. To discuss the challenges of recruiting participants from a minority religious group (the Islamic population) to participate in an interpretive, hermeneutic study concerning the experience of hospitalization. The challenges of recruitment encountered during this study are used as the basis for a broader discussion of this important issue. To ensure the success of this phase of the study, a pre-planned recruitment strategy was essential. Multiple recruitment strategies were used, including hospital-based recruitment, snowball sampling, advertising and contact with key people. Despite the use of multiple strategies, recruitment of participants was difficult and required an extended period of time to achieve sufficiently rich data. Thirteen participants shared their lived experience to provide an in-depth understanding of the phenomenon. Recruiting participants from minority religious group involves potentially sensitive issues. There is an increased need for the researchers to carefully consider potential participants' rights and ensure that sound ethical principles underpin the study, as failure to do this may hinder the recruitment process. The two most effective strategies of recruitment were snowball sampling and contact with key Islamic people, with the least effective being advertising. This paper highlights the importance of anticipating potential difficulties and pre-planning strategies to overcome barriers to recruitment. Implementation of multiple strategies is recommended to ensure successful research recruitment.
Rezaei, Fatemeh; Nedjat, Saharnaz; Golestan, Banafsheh; Majdzadeh, Reza
2011-01-01
Objectives: Identifying the underlying factors contributing to smoking among teenagers is important in establishing smoking control programs. The present study was designed to identify and compare factors revealed in a preceding qualitative study conducted on 13-15 year-old boys living in two different socio-economic districts in the Northern and Southern parts of Tehran. Methods: Two completely similar case-control studies, each with 200 subjects, were conducted using a snowball sampling. The case and control subjects were matched based on the intimacy relations, i.e. six smokers were recruited in each of the Northern and Southern districts; they were then asked to introduce one of their smoker friends as a case and a non-smoker one as a control. Results: Multi-variable conditional logistic regression revealed that having a smoker father is the single effective factor in the two districts. As for boys living in the Northern (wealthier) part of the city, social capital (OR: 0.59, 95% CI: 0.43-0.81) played a protective role against smoking, whereas quitting home after a quarrel (OR: 15.07, 95% CI: 1.54-147.25), monthly allowance (OR: 2.22, 95% CI: 1.29-3.82) and hyperactivity (OR: 1.69, 95% CI: 2.64-240.45) were associated with a higher risk of becoming a smoker. Conclusions: The studied variables can be classified as personal, familial, and school-level factors. Familial intervention is effective for all the factors which revealed to be influential on the risk of becoming a smoker. It could be concluded that interventions on the family level should be used to prevent the cigarette use in Tehran. PMID:22174960
Rezaei, Fatemeh; Nedjat, Saharnaz; Golestan, Banafsheh; Majdzadeh, Reza
2011-10-01
Identifying the underlying factors contributing to smoking among teenagers is important in establishing smoking control programs. The present study was designed to identify and compare factors revealed in a preceding qualitative study conducted on 13-15 year-old boys living in two different socio-economic districts in the Northern and Southern parts of Tehran. Two completely similar case-control studies, each with 200 subjects, were conducted using a snowball sampling. The case and control subjects were matched based on the intimacy relations, i.e. six smokers were recruited in each of the Northern and Southern districts; they were then asked to introduce one of their smoker friends as a case and a non-smoker one as a control. Multi-variable conditional logistic regression revealed that having a smoker father is the single effective factor in the two districts. As for boys living in the Northern (wealthier) part of the city, social capital (OR: 0.59, 95% CI: 0.43-0.81) played a protective role against smoking, whereas quitting home after a quarrel (OR: 15.07, 95% CI: 1.54-147.25), monthly allowance (OR: 2.22, 95% CI: 1.29-3.82) and hyperactivity (OR: 1.69, 95% CI: 2.64-240.45) were associated with a higher risk of becoming a smoker. The studied variables can be classified as personal, familial, and school-level factors. Familial intervention is effective for all the factors which revealed to be influential on the risk of becoming a smoker. It could be concluded that interventions on the family level should be used to prevent the cigarette use in Tehran.
Patterns of Reproductive Isolation in Eucalyptus-A Phylogenetic Perspective.
Larcombe, Matthew J; Holland, Barbara; Steane, Dorothy A; Jones, Rebecca C; Nicolle, Dean; Vaillancourt, René E; Potts, Brad M
2015-07-01
We assess phylogenetic patterns of hybridization in the speciose, ecologically and economically important genus Eucalyptus, in order to better understand the evolution of reproductive isolation. Eucalyptus globulus pollen was applied to 99 eucalypt species, mainly from the large commercially important subgenus, Symphyomyrtus. In the 64 species that produce seeds, hybrid compatibility was assessed at two stages, hybrid-production (at approximately 1 month) and hybrid-survival (at 9 months), and compared with phylogenies based on 8,350 genome-wide DArT (diversity arrays technology) markers. Model fitting was used to assess the relationship between compatibility and genetic distance, and whether or not the strength of incompatibility "snowballs" with divergence. There was a decline in compatibility with increasing genetic distance between species. Hybridization was common within two closely related clades (one including E. globulus), but rare between E. globulus and species in two phylogenetically distant clades. Of three alternative models tested (linear, slowdown, and snowball), we found consistent support for a snowball model, indicating that the strength of incompatibility accelerates relative to genetic distance. Although we can only speculate about the genetic basis of this pattern, it is consistent with a Dobzhansky-Muller-model prediction that incompatibilities should snowball with divergence due to negative epistasis. Different rates of compatibility decline in the hybrid-production and hybrid-survival measures suggest that early-acting postmating barriers developed first and are stronger than later-acting barriers. We estimated that complete reproductive isolation can take up to 21-31 My in Eucalyptus. Practical implications for hybrid eucalypt breeding and genetic risk assessment in Australia are discussed. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Holter, S. A.; Theissen, K. M.; Hickson, T. A.; Bostick, B.
2004-12-01
The Snowball Earth theory of Hoffman et al. (1998) proposes dramatic post-glacial chemical weathering as large concentrations of carbon were removed from the atmosphere. This would result in a large input of terrigenous material into the oceans; hence, we might expect that carbonates formed under these conditions would demonstrate elevated K, U, Th levels in comparison to carbonates formed under more typical conditions. In January of 2004 we collected spectral gamma data (K, U, Th) and hand samples from cap carbonates (Noonday Dolomite) and cap-like carbonates (Beck Spring Dolomite) of the Death Valley region in order to explore elemental changes in post-snowball Earth oceans. Based on our spectral gamma results, Th/U ratio trends suggested variations in the oxidation state of the Precambrian ocean. We pursued further investigations of trace elements to ascertain the reliability of these results by using ICP-OES. A suite of 25 trace elements was measured, most notably including U and Th. The ICP-OES data not only allow us to compare elemental changes between cap-carbonates and cap-like carbonates, but they also allow for a comparison of optical emission spectrometry and hand held gamma spectrometry methods. Both methods show similar trends in U and Th values for both the cap-carbonates and cap-like carbonates.
Lay Perceptions of Healthy Eating Styles and Their Health Impacts.
Vizireanu, Mariya; Hruschka, Daniel
2018-04-01
This study examined perceptions of healthy eating styles among US respondents to determine whether eating styles are defined as a distinct set of people's healthy eating beliefs and how different aspects of eating styles are perceived to affect health. In-person pile sort activities were used to identify key dimensions of healthy eating beliefs, and online surveys were used to confirm these dimensions and examine perceived health benefits of healthy eating styles. The pile-sorting activity recruited 48 US participants in the Phoenix metropolitan area via social media and snowball sampling. Online surveys recruited US participants via Amazon Mechanical Turk (survey 1, n = 70; survey 2, n = 283). The researchers used an exploratory visualizing technique (multidimensional scaling) to analyze pile sort data; Property Filling (PROFIT) analysis was used to analyze online survey 1; paired sample t test and repeated-measures ANOVA were used to analyze online survey 2. Eating styles are a distinct set of beliefs within lay models of healthful diets (P < .001) viewed as important for a number of health outcomes, including weight management. In addition to educating the public about choosing healthy food characteristics, health and nutrition professionals may need to address people's beliefs regarding healthy eating styles to identify gaps and misconceptions. Future research is needed to examine the relationships between such beliefs and corresponding behaviors, as well as whether these behaviors result in any health benefits. Copyright © 2018 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.
[Respondent-Driven Sampling: a new sampling method to study visible and hidden populations].
Mantecón, Alejandro; Juan, Montse; Calafat, Amador; Becoña, Elisardo; Román, Encarna
2008-01-01
The paper introduces a variant of chain-referral sampling: respondent-driven sampling (RDS). This sampling method shows that methods based on network analysis can be combined with the statistical validity of standard probability sampling methods. In this sense, RDS appears to be a mathematical improvement of snowball sampling oriented to the study of hidden populations. However, we try to prove its validity with populations that are not within a sampling frame but can nonetheless be contacted without difficulty. The basics of RDS are explained through our research on young people (aged 14 to 25) who go clubbing, consume alcohol and other drugs, and have sex. Fieldwork was carried out between May and July 2007 in three Spanish regions: Baleares, Galicia and Comunidad Valenciana. The presentation of the study shows the utility of this type of sampling when the population is accessible but there is a difficulty deriving from the lack of a sampling frame. However, the sample obtained is not a random representative one in statistical terms of the target population. It must be acknowledged that the final sample is representative of a 'pseudo-population' that approximates to the target population but is not identical to it.
He, Shanshan; Tsang, Sandra
2016-10-01
Social exchange theory has great potential to help our understanding of dating partners' sexual interaction. Yet, to our knowledge, there is still no empirical study applying this theory to explain sexual coercion in the context of intimate relationships. This study examined the relationship between male partners' social exchange variables (investment and alternatives) and women's coerced first sexual intercourse in dating relationships, within both gender samples (not dyadic data). A total of 927 valid questionnaires were collected by purposive snowball sampling in five main cities in China of college students who were currently in a romantic relationship. Results showed that in the male sample, male partners' investment significantly and positively correlated with emotional manipulation coercive tactics, and their alternatives significantly and positively predicted defection threats as coercive tactics. In the female sample, there were no such observations. The research hypotheses of this study have been partially supported, and its implications and limitations are discussed.
Otis, Melanie D; Skinner, William F
2004-06-01
An exploratory study of lesbians (70) and gay men (118) from a rural state in the mid-South was conducted using a self-administered, mail-out survey. The nonrandom sample was drawn from organizational mailing lists, snowball sampling, and a convenience sample at a community event. Respondents were asked to indicate the extent to which each of the following affected sexual orientation: genetics, relationship between parents, relationship with parents, birth order, peers, growing up in a dysfunctional family, growing up in a single-parent family, negative experiences with the opposite sex, and positive experiences with the same sex. Similar to studies of heterosexual men and women, these gay men were more likely to view sexual orientation as a result of genetics than the lesbian respondents. Further, the lesbian group were more likely to view positive relationships with the same sex to have a great influence on sexual orientation. These data indicate there are sex differences in views on factors that affect sexual orientation.
Pluto's Implications for a Snowball Titan
NASA Astrophysics Data System (ADS)
Wong, M.; Yung, Y. L.; Gladstone, R.
2013-12-01
The recent Cassini-Huygens Mission to the Saturnian system provides compelling evidence that the present state of Titan's dense atmosphere is unsustainable over the age of the Solar System. Instead, for most of the time Titan's atmosphere must have existed in a collapsed snowball state, characterized by a cold surface and a thin atmosphere, much like those of present-day Pluto and Triton. We will briefly review how the present Titan atmosphere exists due to a sensitive coupling between photochemistry, radiation, and dynamics. This delicate 'house of cards' must have collapsed in the past when it ran out of CH4 or when the sun was dimmer. We will investigate how the rate of organic synthesis on Snowball Titan differs from that of contemporary Titan. The forthcoming New Horizons Mission to Pluto and the Kuiper Belt may allow us to gain insights into the fine balance and the evolutionary history of certain planetary atmospheres. In particular, the high SNR solar occultations planned for observation with the Alice UV spectrograph on New Horizons are expected to yield abundance profiles of important hydrocarbons and nitriles in Pluto's atmosphere, providing detailed constraints for photochemical models such as those considered here.
Recruitment Strategies of Methamphetamine-Using Men Who Have Sex with Men into an Online Survey
Wilkerson, J. Michael; Shenk, Jared E.; Grey, Jeremy A.; Simon Rosser, B. R.; Noor, Syed W.
2014-01-01
Recruiting hidden populations into online research remains challenging. In this manuscript, we report lessons learned from our efforts to recruit methamphetamine-using men who have sex with men. Between July and October 2012, we implemented a four-phase recruitment strategy to enroll a total of 343 methamphetamine-using MSM into an online survey about recent substance use, sexual behavior, and various psychosocial measures. The four phases were implemented sequentially. During phase one, we placed advertisements on mobile applications, and during phase two, we placed advertisements on traditional websites formatted for browsers. During phase three, we used e-mail to initiate snowball recruitment, and during phase four, we used social media for snowball recruitment. Advertisements on mobile devices and websites formatted for browsers proved to be expensive options and resulted in few eligible participants. Our attempts to initiate a snowball through e-mail also proved unsuccessful. The majority (n=320) of observations in our final dataset came from our use of social media. However, participant fraud was a concern, requiring us to implement a strong participant verification protocol. For maximum recruitment and cost-effectiveness, researchers should use social media for recruitment provided they employ strong participant verification protocols. PMID:25642143
Recruitment Strategies of Methamphetamine-Using Men Who Have Sex with Men into an Online Survey.
Wilkerson, J Michael; Shenk, Jared E; Grey, Jeremy A; Simon Rosser, B R; Noor, Syed W
Recruiting hidden populations into online research remains challenging. In this manuscript, we report lessons learned from our efforts to recruit methamphetamine-using men who have sex with men. Between July and October 2012, we implemented a four-phase recruitment strategy to enroll a total of 343 methamphetamine-using MSM into an online survey about recent substance use, sexual behavior, and various psychosocial measures. The four phases were implemented sequentially. During phase one, we placed advertisements on mobile applications, and during phase two, we placed advertisements on traditional websites formatted for browsers. During phase three, we used e-mail to initiate snowball recruitment, and during phase four, we used social media for snowball recruitment. Advertisements on mobile devices and websites formatted for browsers proved to be expensive options and resulted in few eligible participants. Our attempts to initiate a snowball through e-mail also proved unsuccessful. The majority (n=320) of observations in our final dataset came from our use of social media. However, participant fraud was a concern, requiring us to implement a strong participant verification protocol. For maximum recruitment and cost-effectiveness, researchers should use social media for recruitment provided they employ strong participant verification protocols.
Pressing the Approach: A NASA Study of 19 Recent Accidents Yields a New Perspective on Pilot Error
NASA Technical Reports Server (NTRS)
Berman, Benjamin A.; Dismukes, R. Key
2007-01-01
This article begins with a review of two sample airplane accidents that were caused by pilot error. The analysis of these and 17 other accidents suggested that almost all experienced pilot operating in the same environment in which the accident crews were operating and knowing only what the accident crews knew at each moment of the flight, would be vulnerable to making a similar decision and similar errors. Whether a particular crew in a given situation makes errors depends on somewhat random interaction of factors. Two themes that seem to be prevalent in these cases are: Plan Continuation Bias, and Snowballing Workload.
An Empirical Analysis of the Default Rate of Informal Lending—Evidence from Yiwu, China
NASA Astrophysics Data System (ADS)
Lu, Wei; Yu, Xiaobo; Du, Juan; Ji, Feng
This study empirically analyzes the underlying factors contributing to the default rate of informal lending. This paper adopts snowball sampling interview to collect data and uses the logistic regression model to explore the specific factors. The results of these analyses validate the explanation of how the informal lending differs from the commercial loan. Factors that contribute to the default rate have particular attributes, while sharing some similarities with commercial bank or FICO credit scoring Index. Finally, our concluding remarks draw some inferences from empirical analysis and speculate as to what this may imply for the role of formal and informal financial sectors.
Plaisime, Marie V; Malebranche, David J; Davis, Andrea L; Taylor, Jennifer A
2017-12-01
We explored health providers' formative personal and professional experiences with race and Black men as a way to assess their potential influence on interactions with Black male patients. Utilizing convenience sampling with snowballing techniques, we identified healthcare providers in two urban university hospitals. We compared Black and White providers' experiences based on race and level of training. We used the Gardener's Tale to conceptualize how racism may lead to racial health disparities. A semi-structured interview guide was used to conduct in-person interviews (n = 16). Using the grounded theory approach, we conducted three types of coding to examine data patterns. We found two themes reflective of personally mediated racism: (1) perception of Black males accompanied by two subthemes (a) biased care and (b) fear and discomfort and (2) cognitive dissonance. While this latter theme is more reflective of Jones's internalized racism level, we present its results because its novelty is compelling. Perception of Black males and cognitive dissonance appear to influence providers' approaches with Black male patients. This study suggests the need to develop initiatives and curricula in health professional schools that address provider racial bias. Understanding the dynamics operating in the patient-provider encounter enhances the ability to address and reduce health disparities.
Ulfers, Sara S; Berg, Christine
2017-07-01
Cancer-related cognitive impairments (CRCI) can limit participation in meaningful activities before, during, and after cancer treatment. This study explored occupational therapists' perceived knowledge gaps and needs regarding CRCI in adults and older adults. An online survey was sent to a convenience sample of 60 practitioners at facilities throughout the continuum of care and 176 directors and faculty in accredited occupational therapy programs. Using a snowball sampling approach, recipients were asked to forward the survey to other occupational therapists. One hundred seven occupational therapists participated. The majority (92%) responded that it would be beneficial to attend a face-to-face continuing education program; preferences for the content and design of a continuing competency seminar are described. These findings support the development and delivery of continuing competence programs tailored toward occupational therapists' CRCI knowledge needs.
Reasons for leaving nursing: a study among Turkish nurses.
Gök, Ayşen Uğur; Kocaman, Gülseren
2011-08-01
Reasons for the growing nursing shortage are often complex and multidimensional. To explore the phenomenon of why Turkish nurses leave nursing. The sample in this descriptive study was 134 nurses who had left the profession. A snowball sampling method was used to identify subjects and multiple methods were used to elicit reasons for leaving. Data analysis included descriptive statistics. The main reasons for leaving nursing were related to unsatisfactory working conditions and a negative perception of nursing. Of the respondents, 69.4% received education in a non-nursing field. The most popular career choice was teaching (27.6%). The results of this study indicate that working conditions and public opinion adversely affect a nurse's interest in the profession. The results of the study indicate a need to improve working conditions and to approach this subject from a multidimensional perspective.
Al-Modallal, Hanan
2016-10-01
The purpose of this study was to examine the cumulative effect of childhood and adulthood violence on depressive symptoms in a sample of Jordanian college women. Snowball sampling technique was used to recruit the participants. The participants were heterosexual college-aged women between the ages of 18 and 25. The participants were asked about their experiences of childhood violence (including physical violence, sexual violence, psychological violence, and witnessing parental violence), partner violence (including physical partner violence and sexual partner violence), experiences of depressive symptoms, and about other demographic and familial factors as possible predictors for their complaints of depressive symptoms. Multiple linear regression analysis was implemented to identify demographic- and violence-related predictors of their complainants of depressive symptoms. Logistic regression analysis was further performed to identify possible type(s) of violence associated with the increased risk of depressive symptoms. The prevalence of depressive symptoms in this sample was 47.4%. For the violence experience, witnessing parental violence was the most common during childhood, experienced by 40 (41.2%) women, and physical partner violence was the most common in adulthood, experienced by 35 (36.1%) women. Results of logistic regression analysis indicated that experiencing two types of violence (regardless of the time of occurrence) was significant in predicting depressive symptoms (odds ratio [OR] = 3.45, p < .05). Among college women's demographic characteristics, marital status (single vs. engaged), mothers' level of education, income, and smoking were significant in predicting depressive symptoms. Assessment of physical violence and depressive symptoms including the cumulative impact of longer periods of violence on depressive symptoms is recommended to be explored in future studies. © The Author(s) 2015.
Adaptive sampling in research on risk-related behaviors.
Thompson, Steven K; Collins, Linda M
2002-11-01
This article introduces adaptive sampling designs to substance use researchers. Adaptive sampling is particularly useful when the population of interest is rare, unevenly distributed, hidden, or hard to reach. Examples of such populations are injection drug users, individuals at high risk for HIV/AIDS, and young adolescents who are nicotine dependent. In conventional sampling, the sampling design is based entirely on a priori information, and is fixed before the study begins. By contrast, in adaptive sampling, the sampling design adapts based on observations made during the survey; for example, drug users may be asked to refer other drug users to the researcher. In the present article several adaptive sampling designs are discussed. Link-tracing designs such as snowball sampling, random walk methods, and network sampling are described, along with adaptive allocation and adaptive cluster sampling. It is stressed that special estimation procedures taking the sampling design into account are needed when adaptive sampling has been used. These procedures yield estimates that are considerably better than conventional estimates. For rare and clustered populations adaptive designs can give substantial gains in efficiency over conventional designs, and for hidden populations link-tracing and other adaptive procedures may provide the only practical way to obtain a sample large enough for the study objectives.
NASA Astrophysics Data System (ADS)
Mellström, Anette; Nilsson, Andreas; Stanton, Tania; Muscheler, Raimund; Snowball, Ian
2013-04-01
Well-dated natural archives are crucial when investigating the timing between climate change and climate forcing. Annually laminated (varved) lake sediments, in particular, can provide valuable knowledge about past climatic and environmental conditions as the annual nature of the sediments enables the establishment of high-resolution archives. In addition, lake sediments can record variations in the Earth's magnetic field, which has the potential to be used as a dating validation technique if the palaeo-secular and -intensity curves are dated correctly. If individual and well-defined geomagnetic events can be dated accurately, they can then be used as isochrones, thereby allowing the synchronisation of different records. We therefore aim to date the "f" event, a late Holocene secular variation change, which is recorded in many sites in the northern hemisphere. Varved sites in Sweden have dated the "f" event to ~2700 cal. yrs BP. In order to constrain this date further, we have used the radiocarbon wiggle-matching method on a lake in central west Sweden, Kälksjön (Stanton et al., 2010), whose chronology has previously been validated using a number of complimentary dating methods. With the radiocarbon wiggle-matching technique, closely spaced samples are measured and matched to distinct wiggles in the radiocarbon calibration curve. The advantage of using varve-dated sediments is that it is possible to know the exact number of years between each sample, and therefore improve the initial age model. We compare the wiggle-match results of Kälksjön with results from a newly discovered varved lake sediment sequence in southern Sweden, Gyltigesjön. This comparison can provide information about magnetisation processes in sediments, such as the length of the palaeomagnetic lock-in delay. Stanton, T., Snowball, I., Zillén, L., Wastegård, S., 2010. Validating a Swedish varve chronology using radiocarbon, palaeomagnetic secular variation, lead pollution history and statistical correlation, Quaternary Geochronology 5, 611-624.
The use of medicinal plants in the trans-himalayan arid zone of Mustang district, Nepal
2010-01-01
Background This study documents the use of medicinal plants from the Mustang district of the north-central part of Nepal. Traditional botanical medicine is the primary mode of healthcare for most of the population of this district and traditional Tibetan doctors (Amchi) serve as the local medical experts. Methods Field research was conducted in 27 communities of the Mustang district in Nepal from 2005-2007. We sampled 202 interviewees, using random and snowball sampling techniques. After obtaining prior informed consent, we collected data through semi-structured interviews and participant-observation techniques. Voucher specimens of all cited botanic species were deposited at TUCH in Nepal. Results We recorded the traditional uses of 121 medicinal plant species, belonging to 49 vascular plant and 2 fungal families encompassing 92 genera. These 121 species are employed to treat a total of 116 ailments. We present data on 58 plant species previously unknown for their medicinal uses in the Mustang district. Of the medicinal plants reported, the most common growth form was herbs (73%) followed by shrubs, trees, and climbers. We document that several parts of individual plant species are used as medicine. Plant parts were generally prepared using hot or cold water as the 'solvent', but occasionally remedies were prepared with milk, honey, jaggery, ghee and oil. Amchis recommended different types of medicine including paste, powder, decoction, tablet, pills, infusion, and others through oral, topical, nasal and others routes of administration. Conclusions The traditional pharmacopoeia of the Mustang district incorporates a myriad of diverse botanical flora. Traditional knowledge of the remedies is passed down through oral traditions and dedicated apprenticeships under the tutelage of senior Amchi. Although medicinal plants still play a pivotal role in the primary healthcare of the local people of Mustang, efforts to ensure the conservation and sustainable use of medicinal species are necessary. PMID:20370901
Contandriopoulos, Damien; Lemire, Marc; Denis, Jean-Louis; Tremblay, Emile
2010-12-01
This article presents the main results from a large-scale analytical systematic review on knowledge exchange interventions at the organizational and policymaking levels. The review integrated two broad traditions, one roughly focused on the use of social science research results and the other focused on policymaking and lobbying processes. Data collection was done using systematic snowball sampling. First, we used prospective snowballing to identify all documents citing any of a set of thirty-three seminal papers. This process identified 4,102 documents, 102 of which were retained for in-depth analysis. The bibliographies of these 102 documents were merged and used to identify retrospectively all articles cited five times or more and all books cited seven times or more. All together, 205 documents were analyzed. To develop an integrated model, the data were synthesized using an analytical approach. This article developed integrated conceptualizations of the forms of collective knowledge exchange systems, the nature of the knowledge exchanged, and the definition of collective-level use. This literature synthesis is organized around three dimensions of context: level of polarization (politics), cost-sharing equilibrium (economics), and institutionalized structures of communication (social structuring). The model developed here suggests that research is unlikely to provide context-independent evidence for the intrinsic efficacy of knowledge exchange strategies. To design a knowledge exchange intervention to maximize knowledge use, a detailed analysis of the context could use the kind of framework developed here. © 2010 Milbank Memorial Fund. Published by Wiley Periodicals Inc.
Contandriopoulos, Damien; Lemire, Marc; Denis, Jean-Louis; Tremblay, Émile
2010-01-01
Context: This article presents the main results from a large-scale analytical systematic review on knowledge exchange interventions at the organizational and policymaking levels. The review integrated two broad traditions, one roughly focused on the use of social science research results and the other focused on policymaking and lobbying processes. Methods: Data collection was done using systematic snowball sampling. First, we used prospective snowballing to identify all documents citing any of a set of thirty-three seminal papers. This process identified 4,102 documents, 102 of which were retained for in-depth analysis. The bibliographies of these 102 documents were merged and used to identify retrospectively all articles cited five times or more and all books cited seven times or more. All together, 205 documents were analyzed. To develop an integrated model, the data were synthesized using an analytical approach. Findings: This article developed integrated conceptualizations of the forms of collective knowledge exchange systems, the nature of the knowledge exchanged, and the definition of collective-level use. This literature synthesis is organized around three dimensions of context: level of polarization (politics), cost-sharing equilibrium (economics), and institutionalized structures of communication (social structuring). Conclusions: The model developed here suggests that research is unlikely to provide context-independent evidence for the intrinsic efficacy of knowledge exchange strategies. To design a knowledge exchange intervention to maximize knowledge use, a detailed analysis of the context could use the kind of framework developed here. PMID:21166865
Re-Os geochronology and coupled Os-Sr isotope constraints on the Sturtian snowball Earth.
Rooney, Alan D; Macdonald, Francis A; Strauss, Justin V; Dudás, Francis Ö; Hallmann, Christian; Selby, David
2014-01-07
After nearly a billion years with no evidence for glaciation, ice advanced to equatorial latitudes at least twice between 717 and 635 Mya. Although the initiation mechanism of these Neoproterozoic Snowball Earth events has remained a mystery, the broad synchronicity of rifting of the supercontinent Rodinia, the emplacement of large igneous provinces at low latitude, and the onset of the Sturtian glaciation has suggested a tectonic forcing. We present unique Re-Os geochronology and high-resolution Os and Sr isotope profiles bracketing Sturtian-age glacial deposits of the Rapitan Group in northwest Canada. Coupled with existing U-Pb dates, the postglacial Re-Os date of 662.4 ± 3.9 Mya represents direct geochronological constraints for both the onset and demise of a Cryogenian glaciation from the same continental margin and suggests a 55-My duration of the Sturtian glacial epoch. The Os and Sr isotope data allow us to assess the relative weathering input of old radiogenic crust and more juvenile, mantle-derived substrate. The preglacial isotopic signals are consistent with an enhanced contribution of juvenile material to the oceans and glacial initiation through enhanced global weatherability. In contrast, postglacial strata feature radiogenic Os and Sr isotope compositions indicative of extensive glacial scouring of the continents and intense silicate weathering in a post-Snowball Earth hothouse.
NASA Astrophysics Data System (ADS)
Maloof, Adam C.; Kellogg, James B.; Anders, Alison M.
2002-11-01
Thermal contraction cracking of permafrost produced sand-wedge polygons at sea level on the paleo-equator during late Neoproterozoic glacial episodes. These sand wedges have been used as evidence for high (≥54°) paleo-obliquity of the Earth's ecliptic, because cracks that form wedges are hypothesized to require deep seasonal cooling so the depth of the stressed layer in the ground reaches ≥1 m, similar to the measured depths of cracks that form wedges. To test the counter hypothesis that equatorial cracks opened under a climate characterized by a strong diurnal cycle and low mean annual temperature (snowball Earth conditions), we examine crack formation in frozen ground subject to periodic temperature variations. We derive analytical expressions relating the Newtonian viscosity to the potential crack depth, concluding that cracks will form only in frozen soils with viscosities greater than ˜10 14 Pa s. We also show numerical calculations of crack growth in frozen soils with stress- and temperature-dependent rheologies and find that fractures may propagate to depths 3-25 times the depth of the thermally stressed layer in equatorial permafrost during a snowball Earth because the mean annual temperature is low enough to keep the ground cold and brittle to relatively great depths.
NASA Astrophysics Data System (ADS)
Abbot, Dorian S.
2016-08-01
The habitable zone concept is important because it focuses the scientific search for extraterrestrial life and aids the planning of future telescopes. Recent work has shown that planets near the outer edge of the habitable zone might not actually be able to stay warm and habitable if CO2 outgassing rates are not large enough to maintain high CO2 partial pressures against removal by silicate weathering. In this paper, I use simple equations for the climate and CO2 budget of a planet in the habitable zone that can capture the qualitative behavior of the system. With these equations I derive an analytical formula for an effective outer edge of the habitable zone, including limitations imposed by the CO2 outgassing rate. I then show that climate cycles between a snowball state and a warm climate are only possible beyond this limit if the weathering rate in the snowball climate is smaller than the CO2 outgassing rate (otherwise stable snowball states result). I derive an analytical solution for the climate cycles including a formula for their period in this limit. This work allows us to explore the qualitative effects of weathering processes on the effective outer edge of the habitable zone, which is important because weathering parameterizations are uncertain.
NASA Astrophysics Data System (ADS)
Abbot, D. S.
2016-12-01
The habitable zone concept is important because it focuses the scientific search for extraterrestrial life and aids the planning of future telescopes. Recent work has shown that planets near the outer edge of the habitable zone might not actually be able to stay warm and habitable if CO2 outgassing rates are not large enough to maintain high CO2 partial pressures against removal by silicate weathering. I use simple equations for the climate and CO2 budget of a planet in the habitable zone that can capture the qualitative behavior of the system. With these equations I derive an analytical formula for an effective outer edge of the habitable zone, including limitations imposed by the CO2 outgassing rate. I then show that climate cycles between a Snowball state and a warm climate are only possible beyond this limit if the weathering rate in the Snowball climate is smaller than the CO2 outgassing rate (otherwise stable Snowball states result). I derive an analytical solution for the climate cycles including a formula for their period in this limit. This work allows us to explore the qualitative effects of weathering processes on the effective outer edge of the habitable zone, which is important because weathering parameterizations are uncertain.
Predicting relative sea level changes at the aftermath of Marinoan (635 Ma) Snowball meltdown
NASA Astrophysics Data System (ADS)
Irie, Y.; Nakada, M.; Okuno, J.; Bao, H.
2016-12-01
Earth system recovery from a Snowball state constitutes one of the best tests of the resilience of life on planet Earth. A distinct and probably brief relative sea level (RSL) drop has been identified in the cap dolostones deposited in a general transgression sequence at the aftermath of Marinoan Snowball meltdown in South China and other late Neoproterozoic blocks. However, the magnitude and duration or the very existence of this RSL drop event can vary at different geographical sites because of spatial and temporal variations in sea level due to glacial isostatic adjustment (GIA) even for tectonically stable areas. An accurate prediction of this drop can in turn help us infer independently the rate of dynamic recovery of the Earth system from a Snowball state, e.g. the timing and duration of the Marinoan 17O depletion (MOSD) event that was also closely linked to the rise and drawdown of atmospheric O2 and CO2, respectively. Here we model the RSL changes by considering all GIA-related relaxation processes. We evaluated the RSL to the sea level at 10 Myr after the complete glacial meltdown and tested slightly different paleogeographic configurations. Our modeling results show that the RSL drop occurs in the syn-deglacial phase (melting phase) for the inland regions and in the post-deglacial phase (time after the complete melting) for continental margins. The RSL drop in the post-deglacial phase is mainly determined by the relaxation processes with a timescale of longer than 20 kyr. The predicted RSL change in South China for lower mantle viscosity of 1022-1023 Pa s and a syn-deglacial time of <100 kyr is consistent with the observationally inferred RSL change regardless of uncertainties on the length of the continental shelf or the paleogeography of South China. A comparison between our model predicted and sedimentary-record inferred RSL change in South China put an independent constraint on the duration of the MOSD event at 70 kyr or shorter.
Weng, Suzie S; Spaulding-Givens, Jennifer
2017-09-01
This qualitative study used snowball sampling of individuals known to provide informal assistance to Asian American community members with their mental health problems in a locality in the South where there has been an exponential increase of the Asian American population. The major themes found include: (1) the existence of cultural, language, knowledge, and transportation barriers and the importance of policy in addressing them; (2) the impact of the model minority myth and the need for inclusive policymaking; and (3) the unique service and policy needs of immigrants. Findings demonstrate the importance and value of including diverse Asian American individuals in mental health policymaking efforts.
Neoproterozoic paleomagnetic poles in the Taoudeni basin (West Africa)
NASA Astrophysics Data System (ADS)
Boudzoumou, Florent; Vandamme, Didier; Affaton, Pascal; Gattacceca, Jérôme
2011-04-01
A palaeomagnetic study was carried out on Neoproterozoic samples from seven sites of the sub-basins of Gourma and Bobo Dioulasso, which include a Marinoan glaciogenic deposit. Magnetic mineralogy is represented essentially by magnetite and hematite. The mean directions of the sites are calculated on the high temperature component (500-670 °C). Two locations provide data constrained by statistical reversal and fold tests and determining Neoproterozoic virtual geomagnetic poles. The palaeolatitudes display very low values which place the West-African craton in the sub-equatorial position during the Marinoan glaciation. This result enhances the Snowball Earth hypothesis, which places most of the continental landmasses, and notably Africa, at low latitudes during the Neoproterozoic.
Effects of a Pedagogical Agent's Emotional Expressiveness on Learner Perceptions
NASA Technical Reports Server (NTRS)
Romero, Enilda J.; Watson, Ginger S.
2012-01-01
The use of animated pedagogical agents or avatars in instruction has lagged behind their use in entertainment. This is due in part to the cost and complexity of development and implementation of agents in educational settings, but also results from a lack of research to understand how emotions from animated agents influence instructional effectiveness. The phenomenological study presented here assesses the perceptions of eight learners interacting with low and high intensity emotionally expressive pedagogical agents in a computer-mediated environment. Research methods include maximum variation and snowball sampling with random assignment to treatment. The resulting themes incorporate perceptions of importance, agent humanness, enjoyment, implementation barriers, and suggested improvements. Design recommendations and implications for future research are presented.
Factors controlling the initiation of Snowball Earth events
NASA Astrophysics Data System (ADS)
Voigt, A.
2012-12-01
During the Neoproterozoic glaciations tropical continents were covered by active glaciers that extended down to sea level. To explain these glaciers, the Snowball Earth hypothesis assumes that oceans were completely sea-ice covered during these glaciation, but there is an ongoing debate whether or not some regions of the tropical oceans remained open. In this talk, I will describe past and ongoing climate modelling activities with the comprehensive coupled climate model ECHAM5/MPI-OM that identify and compare factors that control the initiation of Snowball Earth events. I first show that shifting the continents from their present-day location to their Marinoan (635 My BP) low-latitude location increases the planetary albedo, cools the climate, and thereby allows Snowball Earth initiation at higher levels of total solar irradiance and atmospheric CO2. I then present simulations with successively lowered bare sea-ice albedo, disabled sea-ice dynamics, and switched-off ocean heat transport. These simulations show that both lowering the bare sea-ice albedo and disabling sea-ice dynamics increase the critical sea-ice cover in ECHAM5/MPI-OM, but sea-ice dynamics due to strong equatorward sea-ice transport have a much larger influence on the critical CO2. Disabling sea-ice transport allows a state with sea-ice margin at 10 deg latitude by virtue of the Jormungand mechanism. The accumulation of snow on land, in combination with tropical land temperatures below or close to freezing, suggests that tropical land glaciers could easily form in such a state. However, in contrast to aquaplanet simulations without ocean heat transport, there is no sign of a Jormungand hysteresis in the coupled simulations. Ocean heat transport is not responsible for the lack of a Jormungand hysteresis in the coupled simulations. By relating the above findings to previous studies, I will outline promising future avenues of research on the initiation of Snowball Earth events. In particular, an improved understanding and modelling of sea-ice dynamics is needed.ea-ice cover as a function of CO2 for ECHAM5/MPI-OM simulations with high bare sea-ice albedo (black circles), low bare sea-ice albedo (blue squares), low bare sea-ice albedo and disabled sea-ice dynamics (red triangles), and low bare sea-ice albedo, disabled sea-ice dynamics and zero ocean heat transport (green diamonds). All simulations use Marinoan low-latitude continents and a solar constant reduced to 94% of its modern value.
Hadley cell dynamics of a cold and virtually dry Snowball Earth atmosphere
NASA Astrophysics Data System (ADS)
Voigt, Aiko; Held, Isaac; Marotzke, Jochem
2010-05-01
We use the full-physics atmospheric general circulation model ECHAM5 to investigate a cold and virtually dry Snowball Earth atmosphere that results from specifying sea ice as the surface boundary condition everywhere, corresponding to a frozen aquaplanet, while keeping total solar irradiance at its present-day value of 1365 Wm-2. The aim of this study is the investigation of the zonal-mean circulation of a Snowball Earth atmosphere, which, due to missing moisture, might constitute an ideal though yet unexplored testbed for theories of atmospheric dynamics. To ease comparison with theories, incoming solar insolation follows permanent equinox conditions with disabled diurnal cycle. The meridional circulation consists of a thermally direct cell extending from the equator to 45 N/S with ascent in the equatorial region, and a weak thermally indirect cell with descent between 45 and 65 N/S and ascent in the polar region. The former cell corresponds to the present-day Earth's Hadley cell, while the latter can be viewed as an eddy-driven Ferrell cell; the present-day Earth's direct polar cell is missing. The Hadley cell itself is subdivided into a vigorous cell confined to the troposphere and a weak deep cell reaching well into the stratosphere. The dynamics of the vigorous Snowball Earth Hadley cell differ substantially from the dynamics of the present-day Hadley cell. The zonal momentum balance shows that in the poleward branch of the vigorous Hadley cell, mean flow meridional advection of absolute vorticity is not only balanced by eddy momentum flux convergence but also by vertical diffusion. Inside the poleward branch, eddies are more important in the upper part and vertical diffusion is more important in the lower part. Vertical diffusion also contributes to the meridional momentum balance as it decelerates the vigorous Hadley cell by downgradient momentum mixing between its poleward and equatorward branch. Zonal winds, therefore, are not in thermal wind balance in the vigorous Hadley cell. Suppressing vertical momentum diffusion above 870 hPa results in a doubling of the vigorous Hadley cell strength. Simulations where we only suppress either vertical diffusion of zonal or meridional momentum show that this doubling can be understood from the decelerating effect of vertical diffusion in the meridional momentum balance. Comparing our simulations with theories, we conclude that neither the axisymmetric Hadley cell model of Held & Hou (1980) nor the eddy-permitting model of T. Schneider et al. (2005, 2006, 2008) are applicable to a Snowball Earth atmosphere since both assume an inviscid upper Hadley cell branch.
Báez-Montiel, Brenda Beatriz; Gutiérrez-Islas, Elizabeth; Bolaños-Maldonado, Margarita; Samarín, Elena; Turabián, José Luis
2014-02-01
To examine the professional profile of the family doctor in different countries and the social welfare context where their work is carried out. Qualitative Methodology of production of field diaries of a normal day. Primary Heath Care of Toledo and Tenerife in Spain, and Paraguay, Mexico, and Peru. Non-random sampling, intentional, followed by snowball sample until data saturation. Participants wrote a diary of a typical day's work, their circumstances and socio-health context, and were studied by content analysis. Techniques to control the biases were used the check the participants and the triangulation between the obtained results and the existing bibliography, and data found on the Internet daily. We performed a mental map to transcribe the results graphically and in a comprehensive form. A total of 24 diaries of a normal day were obtained (9 doctors in Spain, 7 in Mexico, 4 in Paraguay, and 4 in Peru). We found some similarities, but many differences between countries. In contexts of humble but spirited, rural, with traditional roots and undemanding, there was a wider range of tasks of the family doctor, the coexistence of public and private work, and modern and traditional medicine, with greater presence of family and community care, more physician satisfaction and better patient-physician relationship. The professional profile of the family doctor is diverse and a context-dependent variable, and is not derived directly from external theory of family medicine. Copyright © 2013 Elsevier España, S.L. All rights reserved.
See Wan, Ong; Hassali, Mohamed Azmi; Saleem, Fahad
2017-01-01
The Internet is a resource used by health professionals as well as the public to access health information. Within this context, little is reported on community pharmacists' (CPs') perceptions of online health-related information. The objective of this study was to explore the attitudes of Malaysian CPs towards online health-related information. A qualitative research method was adopted with face-to-face interviews, using a semi-structured interview guide. Purposive and snowball sampling techniques were used to recruit a convenient sample of CPs who were practising in the Federal Territory of Kuala Lumpur, Malaysia. All interviews were audio recorded and transcribed verbatim. The data were analysed by the research team using a thematic content analysis framework. Eleven CPs participated in the study. Participants reported that online health-related information was accessible, useful, fast, and in some respects, the Internet is a unique source of information. It was reported that there was a need to establish websites for trusted information. CPs also reported that training was needed in Internet searching and website evaluation skills. Most information accessed by CPs related to drugs and diseases and to knowledge-based information. Barriers to efficacy of Internet usage were related to the reliability and volume of information available on the Internet. Frequent use of online health-related information among CPs was reported. Many CPs supported the use of the Internet for health-related information but certain reservations were also reported. An analysis of the reasons for information seeking and barriers suggests that a wider range of influences on health information seeking should be investigated.
Auxiliary Parameter MCMC for Exponential Random Graph Models
NASA Astrophysics Data System (ADS)
Byshkin, Maksym; Stivala, Alex; Mira, Antonietta; Krause, Rolf; Robins, Garry; Lomi, Alessandro
2016-11-01
Exponential random graph models (ERGMs) are a well-established family of statistical models for analyzing social networks. Computational complexity has so far limited the appeal of ERGMs for the analysis of large social networks. Efficient computational methods are highly desirable in order to extend the empirical scope of ERGMs. In this paper we report results of a research project on the development of snowball sampling methods for ERGMs. We propose an auxiliary parameter Markov chain Monte Carlo (MCMC) algorithm for sampling from the relevant probability distributions. The method is designed to decrease the number of allowed network states without worsening the mixing of the Markov chains, and suggests a new approach for the developments of MCMC samplers for ERGMs. We demonstrate the method on both simulated and actual (empirical) network data and show that it reduces CPU time for parameter estimation by an order of magnitude compared to current MCMC methods.
Vermette, David; Shetgiri, Rashmi; Al Zuheiri, Haidar; Flores, Glenn
2015-10-01
To identify access barriers to healthcare and potential interventions to improve access for Iraqi refugee children. Four focus groups were conducted using consecutive sampling of Iraqi refugee parents residing in the US for 8 months to 5 years. Eight key-informant interviews also were conducted with employees of organizations serving Iraqi refugee families, recruited using snowball sampling. Focus groups and interviews were audiotaped, transcribed, and analyzed using margin coding and grounded theory. Iraqi refugees identified provider availability, Medicaid maintenance and renewal, language issues, and inadequate recognition of post-traumatic stress disorder as barriers to care for their children. Interviewees cited loss of case-management services and difficulties in understanding the Medicaid renewal process as barriers. Potential interventions to improve access include community-oriented efforts to educate parents on Medicaid renewal, obtaining services, and accessing specialists. Given the enduring nature of language and Medicaid renewal barriers, policies addressing eligibility alone are insufficient.
Warnke, Ingeborg; Gamma, Alex; Buadze, Maria; Schleifer, Roman; Canela, Carlos; Strebel, Bernd; Tényi, Tamás; Rössler, Wulf; Rüsch, Nicolas; Liebrenz, Michael
2018-01-01
Psychiatry as a medical discipline is becoming increasingly important due to the high and increasing worldwide burden associated with mental disorders. Surprisingly, however, there is a lack of young academics choosing psychiatry as a career. Previous evidence on medical students’ perspectives is abundant but has methodological shortcomings. Therefore, by attempting to avoid previous shortcomings, we aimed to contribute to a better understanding of the predictors of the following three outcome variables: current medical students’ attitudes toward psychiatry, interest in psychiatry, and estimated likelihood of working in psychiatry. The sample consisted of N = 1,356 medical students at 45 medical schools in Germany and Austria as well as regions of Switzerland and Hungary with a German language curriculum. We used snowball sampling via Facebook with a link to an online questionnaire as recruitment procedure. Snowball sampling is based on referrals made among people. This questionnaire included a German version of the Attitudes Toward Psychiatry Scale (ATP-30-G) and further variables related to outcomes and potential predictors in terms of sociodemography (e.g., gender) or medical training (e.g., curriculum-related experience with psychiatry). Data were analyzed by linear mixed models and further regression models. On average, students had a positive attitude to and high general interest in, but low professional preference for, psychiatry. A neutral attitude to psychiatry was partly related to the discipline itself, psychiatrists, or psychiatric patients. Female gender and previous experience with psychiatry, particularly curriculum-related and personal experience, were important predictors of all outcomes. Students in the first years of medical training were more interested in pursuing psychiatry as a career. Furthermore, the country of the medical school was related to the outcomes. However, statistical models explained only a small proportion of variance. The findings indicate that particularly curriculum-related experience is important for determining attitudes toward psychiatry, interest in the subject and self-predicted professional career choice. We therefore encourage the provision of opportunities for clinical experience by psychiatrists. However, further predictor variables need to be considered in future studies. PMID:29593577
Gigapixel imaging as a resource for geoscience teaching, research, and outreach
NASA Astrophysics Data System (ADS)
Bentley, C.; Pitts, A.; Rohrback, R. C.; Dudek, M.
2015-12-01
The Mid-Atlantic Geo-Image Collection is a repository of gigapixel-resolution geologic imagery intended as a tool for geoscience professionals, educators, students, & researchers (http://gigapan.com/groups/100/galleries). GigaPan provides a unique combination of context & detail, with images that maintain a high level of resolution through every level of magnification. Using geological GigaPans, physically disabled students can participate in virtual field trips, instructors can bring inaccessible outcrops into the classroom, & students can zoom in on hand samples without expensive microscopes. Because GigaPan images permit detailed visual examination of geologic, MAGIC is particularly suitable for use in online geology courses. The images are free to use and tag. Our 10 contributors (3 faculty, 2 graduate students, & 6 undergraduates) use 4 models of mobile robot cameras (outcrop/landscape), 2 laboratory-based GIGAmacro imaging systems (hand samples) & 2 experimental units: 1 for thin sections, 1 for GigaPans of scanning electron microscopy. Each of these has strengths & weaknesses. MAGIC has suites of images of Appalachian structure & stratigraphy, Rocky Mountains, Snowball Earth hypothesis, & doomed outcrops of Miocene strata on Chesapeake Bay. Virtual field trips with our imagery have been developed for: Billy Goat Trail, MD; Helen Lake, AB; Wind River Canyon, WY; the Canadian Rockies; El Paso, TX; glaciation around the world; and Corridor H, WV (a GSA field trip in Nov. 2015). Virtual sample sets have been developed for introductory minerals, igneous, sedimentary, & metamorphic rocks, the stratigraphy of VA's physiographic provinces, & the Snowball Earth hypothesis. The virtual field trips have been tested in both online & onsite courses. There are close to a thousand images in the collection, each averaging about 0.9 gigapixels in size, with close to 900,000 views total. A new viewer for GigaPans was released this year by GIGAmacro. This new viewer allows measurement and calibration, automatically resizing scale bars, side-by-side comparisons between 2 images, overlapping presentation of 2 images, & annotation by users. Comparative viewers are particularly useful for the presentation of before/after imagery; raw vs. annotated imagery, & polarized views of thin sections.
Warnke, Ingeborg; Gamma, Alex; Buadze, Maria; Schleifer, Roman; Canela, Carlos; Strebel, Bernd; Tényi, Tamás; Rössler, Wulf; Rüsch, Nicolas; Liebrenz, Michael
2018-01-01
Psychiatry as a medical discipline is becoming increasingly important due to the high and increasing worldwide burden associated with mental disorders. Surprisingly, however, there is a lack of young academics choosing psychiatry as a career. Previous evidence on medical students' perspectives is abundant but has methodological shortcomings. Therefore, by attempting to avoid previous shortcomings, we aimed to contribute to a better understanding of the predictors of the following three outcome variables: current medical students' attitudes toward psychiatry, interest in psychiatry, and estimated likelihood of working in psychiatry. The sample consisted of N = 1,356 medical students at 45 medical schools in Germany and Austria as well as regions of Switzerland and Hungary with a German language curriculum. We used snowball sampling via Facebook with a link to an online questionnaire as recruitment procedure. Snowball sampling is based on referrals made among people. This questionnaire included a German version of the Attitudes Toward Psychiatry Scale (ATP-30-G) and further variables related to outcomes and potential predictors in terms of sociodemography (e.g., gender) or medical training (e.g., curriculum-related experience with psychiatry). Data were analyzed by linear mixed models and further regression models. On average, students had a positive attitude to and high general interest in, but low professional preference for, psychiatry. A neutral attitude to psychiatry was partly related to the discipline itself, psychiatrists, or psychiatric patients. Female gender and previous experience with psychiatry, particularly curriculum-related and personal experience, were important predictors of all outcomes. Students in the first years of medical training were more interested in pursuing psychiatry as a career. Furthermore, the country of the medical school was related to the outcomes. However, statistical models explained only a small proportion of variance. The findings indicate that particularly curriculum-related experience is important for determining attitudes toward psychiatry, interest in the subject and self-predicted professional career choice. We therefore encourage the provision of opportunities for clinical experience by psychiatrists. However, further predictor variables need to be considered in future studies.
NASA Astrophysics Data System (ADS)
Rowan, C. J.; Tait, J.
2010-12-01
Glaciogenic diamictites and associated ‘cap’ carbonates within the Neoproterozoic Huqf Supergroup of Oman record a period of extreme, possibly global, glaciations between 750-635 Ma (the "Snowball Earth"). We have performed high-resolution paleomagnetic sampling of two sections through ~635 Ma cap carbonates in the Jebel Akhdar region of northern Oman. Stepwise thermal demagnetisation reveals a low temperature component carried by goethite, and a high temperature component carried by haematite, that are both aligned with the modern dipole field direction. Occasional reversed polarity directions antipodal to the present day field indicate pervasive weathering of these outcrops over timescales of at least 1 Ma. Between these two overprints an intermediate component with typical unblocking temperatures of 300-550 C, probably carried by magnetite, can also be isolated in most samples. A robust fold test clearly demonstrates that this component was acquired after Paleozoic folding of the carbonates, and was most likely acquired during exhumation associated with emplacement of the Semail ophiolite during the Late Cretaceous (95-68 Ma). In geographic co-ordinates, the intermediate component has an almost horizontal NNW or SSE direction, similar to directions previously reported from outcrops of the ophiolite close to the Jebel Akhdar region, and from thermally altered basement rocks in the the Saih Hatat window further to the east [Feinberg et al. 1999]. Hints of an older, Permian, remagnetisation of the carbonates, which is also observed in the Saih Hatat basement rocks, have also produced a false polarity stratigraphy in one of the sampled sections. Our results contrast with the previously reported low latitude pole from the Huqf Supergroup [Kilner et al., 2005], which was considered to be amongst the more reliable paleomagnetic data supporting glaciations extending to low latitudes during the late Neoproterozoic. However, this interpretation was made on the basis of lower resolution sampling of only shallowly dipping sequences, and it is clear that this low-latitude pole was calculated from the same magnetic component that we have definitively shown to be a later remagnetisation. The paleolatitude of Oman during the Late Neoproterozoic glaciations therefore remains unconstrained, although paleomagnetic analysis of volcanic and sedimentary units in the Huqf Supergroup that bracket the glacial formations may yet yield a primary remanence.
Episode of intense chemical weathering during the termination of the 635 Ma Marinoan glaciation.
Huang, Kang-Jun; Teng, Fang-Zhen; Shen, Bing; Xiao, Shuhai; Lang, Xianguo; Ma, Hao-Ran; Fu, Yong; Peng, Yongbo
2016-12-27
Cryogenian (∼720-635 Ma) global glaciations (the snowball Earth) represent the most extreme ice ages in Earth's history. The termination of these snowball Earth glaciations is marked by the global precipitation of cap carbonates, which are interpreted to have been driven by intense chemical weathering on continents. However, direct geochemical evidence for the intense chemical weathering in the aftermath of snowball glaciations is lacking. Here, we report Mg isotopic data from the terminal Cryogenian or Marinoan-age Nantuo Formation and the overlying cap carbonate of the basal Doushantuo Formation in South China. A positive excursion of extremely high δ 26 Mg values (+0.56 to +0.95)-indicative of an episode of intense chemical weathering-occurs in the top Nantuo Formation, whereas the siliciclastic component of the overlying Doushantuo cap carbonate has significantly lower δ 26 Mg values (<+0.40), suggesting moderate to low intensity of chemical weathering during cap carbonate deposition. These observations suggest that cap carbonate deposition postdates the climax of chemical weathering, probably because of the suppression of carbonate precipitation in an acidified ocean when atmospheric CO 2 concentration was high. Cap carbonate deposition did not occur until chemical weathering had consumed substantial amounts of atmospheric CO 2 and accumulated high levels of oceanic alkalinity. Our finding confirms intense chemical weathering at the onset of deglaciation but indicates that the maximum weathering predated cap carbonate deposition.
ERIC Educational Resources Information Center
Scherr, Charles W.
1979-01-01
Shows that the elementary ballistic range problem solution, when scaled by the reciprocal of the eccentricity, contains in itself a good description of the more general Keplerian ballistic problem. (Author/GA)
Jung, Minsoo
2015-01-01
When there is no sampling frame within a certain group or the group is concerned that making its population public would bring social stigma, we say the population is hidden. It is difficult to approach this kind of population survey-methodologically because the response rate is low and its members are not quite honest with their responses when probability sampling is used. The only alternative known to address the problems caused by previous methods such as snowball sampling is respondent-driven sampling (RDS), which was developed by Heckathorn and his colleagues. RDS is based on a Markov chain, and uses the social network information of the respondent. This characteristic allows for probability sampling when we survey a hidden population. We verified through computer simulation whether RDS can be used on a hidden population of cancer survivors. According to the simulation results of this thesis, the chain-referral sampling of RDS tends to minimize as the sample gets bigger, and it becomes stabilized as the wave progresses. Therefore, it shows that the final sample information can be completely independent from the initial seeds if a certain level of sample size is secured even if the initial seeds were selected through convenient sampling. Thus, RDS can be considered as an alternative which can improve upon both key informant sampling and ethnographic surveys, and it needs to be utilized for various cases domestically as well.
Who Are the Most Influential Emergency Physicians on Twitter?
Riddell, Jeff; Brown, Alisha; Kovic, Ivor; Jauregui, Joshua
2017-01-01
Introduction Twitter has recently gained popularity in emergency medicine (EM). Opinion leaders on Twitter have significant influence on the conversation and content, yet little is known about these opinion leaders. We aimed to describe a methodology to identify the most influential emergency physicians (EP) on Twitter and present a current list. Methods We analyzed 2,234 English-language EPs on Twitter from a previously published list of Twitter accounts generated by a snowball sampling technique. Using NodeXL software, we performed a network analysis of these EPs and ranked them on three measures of influence: in-degree centrality, eigenvector centrality, and betweenness centrality. We analyzed the top 100 users in each of these three measures of influence and compiled a list of users found in the top 100 in all three measures. Results Of the 300 total users identified by one of the measures of influence, there were 142 unique users. Of the 142 unique users, 61 users were in the top 100 on all three measures of influence. We identify these 61 users as the most influential EM Twitter users. Conclusion We both describe a method for identifying the most influential users and provide a list of the 61 most influential EPs on Twitter as of January 1, 2016. This application of network science to the EM Twitter community can guide future research to better understand the networked global community of EM. PMID:28210365
Maternal and Child Health of Internally Displaced Persons in Ukraine: A Qualitative Study
Nidzvetska, Svitlana; Rodriguez-Llanes, Jose M.; Aujoulat, Isabelle; Gil Cuesta, Julita; Tappis, Hannah; van Loenhout, Joris A. F.; Guha-Sapir, Debarati
2017-01-01
Due to the conflict that started in spring 2014 in Eastern Ukraine, a total of 1.75 million internally displaced persons (IDPs) fled the area and have been registered in government-controlled areas of the country. This paper explores perceived health, barriers to access to healthcare, caring practices, food security, and overall financial situation of mothers and young children displaced by the conflict in Ukraine. This is a qualitative study, which collected data through semi-structured in-depth interviews with nine IDP mothers via Skype and Viber with a convenience sample of participants selected through snowball technique. Contrary to the expectations, the perceived physical health of mothers and their children was found not to be affected by conflict and displacement, while psychological distress was often reported. A weak healthcare system, Ukraine’s proneness to informal payments, and heavy bureaucracy to register as an IDP were reported in our study. A precarious social safety net to IDP mothers in Ukraine, poor dietary diversity, and a generalized rupture of vaccine stocks, with halted or delayed vaccinations in children were identified. Increasing social allowances and their timely delivery to IDP mothers might be the most efficient policy measure to improve health and nutrition security. Reestablishment and sustainability of vaccine stocks in Ukraine is urgent to avoid the risks of a public health crisis. Offering psychological support for IDP mothers is recommended. PMID:28075363
Who Are the Most Influential Emergency Physicians on Twitter?
Riddell, Jeff; Brown, Alisha; Kovic, Ivor; Jauregui, Joshua
2017-02-01
Twitter has recently gained popularity in emergency medicine (EM). Opinion leaders on Twitter have significant influence on the conversation and content, yet little is known about these opinion leaders. We aimed to describe a methodology to identify the most influential emergency physicians (EP) on Twitter and present a current list. We analyzed 2,234 English-language EPs on Twitter from a previously published list of Twitter accounts generated by a snowball sampling technique. Using NodeXL software, we performed a network analysis of these EPs and ranked them on three measures of influence: in-degree centrality, eigenvector centrality, and betweenness centrality. We analyzed the top 100 users in each of these three measures of influence and compiled a list of users found in the top 100 in all three measures. Of the 300 total users identified by one of the measures of influence, there were 142 unique users. Of the 142 unique users, 61 users were in the top 100 on all three measures of influence. We identify these 61 users as the most influential EM Twitter users. We both describe a method for identifying the most influential users and provide a list of the 61 most influential EPs on Twitter as of January 1, 2016. This application of network science to the EM Twitter community can guide future research to better understand the networked global community of EM.
Maternal and Child Health of Internally Displaced Persons in Ukraine: A Qualitative Study.
Nidzvetska, Svitlana; Rodriguez-Llanes, Jose M; Aujoulat, Isabelle; Gil Cuesta, Julita; Tappis, Hannah; van Loenhout, Joris A F; Guha-Sapir, Debarati
2017-01-09
Due to the conflict that started in spring 2014 in Eastern Ukraine, a total of 1.75 million internally displaced persons (IDPs) fled the area and have been registered in government-controlled areas of the country. This paper explores perceived health, barriers to access to healthcare, caring practices, food security, and overall financial situation of mothers and young children displaced by the conflict in Ukraine. This is a qualitative study, which collected data through semi-structured in-depth interviews with nine IDP mothers via Skype and Viber with a convenience sample of participants selected through snowball technique. Contrary to the expectations, the perceived physical health of mothers and their children was found not to be affected by conflict and displacement, while psychological distress was often reported. A weak healthcare system, Ukraine's proneness to informal payments, and heavy bureaucracy to register as an IDP were reported in our study. A precarious social safety net to IDP mothers in Ukraine, poor dietary diversity, and a generalized rupture of vaccine stocks, with halted or delayed vaccinations in children were identified. Increasing social allowances and their timely delivery to IDP mothers might be the most efficient policy measure to improve health and nutrition security. Reestablishment and sustainability of vaccine stocks in Ukraine is urgent to avoid the risks of a public health crisis. Offering psychological support for IDP mothers is recommended.
Religion and Culture Encounters in Misool Raja Ampat: Marine Ritual Practice of Sasi Laut
NASA Astrophysics Data System (ADS)
Suardi Wekke, Ismail; Aghsari, Diah; Evizariza, Evizariza; Junaidi, Junaidi; Harun, Nurlaila
2018-05-01
The acculturation of religion and culture in such a way are gradually accepted without causing the loss of the native culture in one community will influence the social process. When religion and culture arise and merged into one, it can be clear to be found in their rituals. This ethnography study on qualitative in nature was conducted to see how the existence, practices, and acculturation between local culture and Islam in, Sasi marine rituals in Misool Raja Ampat in West Papua Indonesia. Data collection was done through observation, in-depth interview including library research on community manuscript and local government database. Using snowball sampling technique, this study is able to gain solid information from native people in Misoo that willing to take part as the informants. The informants in this study were found as influences native people in Misool community e.g; the head of Fafanlap village, community figures, female figures and youth figures. This study considers Misool community which still strongly maintains their cultures including sasi laut as a sign to start and stop harvesting the specific sea resources to maintain the sustainability of nature. The acculturation between the culture of Islam runs smoothly in changing the native mindset to eliminate the things that can cause syirik but did not eliminate the characteristics and the main part of the ritual of sasi laut.
Women's lives in times of Zika: mosquito-controlled lives?
Linde, Ana Rosa; Siqueira, Carlos Eduardo
2018-05-10
Zika virus infection during pregnancy is a cause of congenital brain abnormalities. Its consequences to pregnancies has made governments, national and international agencies issue advices and recommendations to women. There is a clear need to investigate how the Zika outbreak affects the decisions that women take concerning their lives and the life of their families, as well as how women are psychologically and emotionally dealing with the outbreak. We conducted a qualitative study to address the impact of the Zika epidemic on the family life of women living in Brazil, Puerto Rico, and the US, who were affected by it to shed light on the social repercussions of Zika. Women were recruited through the snowball sampling technique and data was collected through semi-structured interviews. We describe the effects in mental health and the coping strategies that women use to deal with the Zika epidemic. Zika is taking a heavy toll on women's emotional well-being. They are coping with feelings of fear, helplessness, and uncertainty by taking drastic precautions to avoid infection that affect all areas of their lives. Coping strategies pose obstacles in professional life, lead to social isolation, including from family and partner, and threaten the emotional and physical well-being of women. Our findings suggest that the impacts of the Zika epidemic on women may be universal and global. Zika infection is a silent and heavy burden on women's shoulders.
Perceived Benefits and Barriers of Cervical Cancer Screening Among Chinese American Women.
Tung, Wei-Chen; Lu, Minggen; Granner, Michelle
2017-03-01
To explore the perceived benefits and barriers to cervical cancer screening among Chinese American women using stages of the Transtheoretical Model of Change. . Cross-sectional design with self-report surveys. . Chinese communities (e.g., churches, supermarkets, restaurants) in Northern California and Northern Nevada. . 121 Chinese women aged 21-65 years living in Northern California and Northern Nevada. . A snowball sampling technique using personal contacts was used. . Stages of change and perceived benefits and barriers to cervical cancer screening. . Participants in the action/maintenance stage were most likely to believe that cervical cancer was treatable if caught early. Women in the contemplation/preparation stage were more likely to state that they worried about or feared screening, that it was too expensive, and that they would want to use Chinese medicine to cure an illness before trying Western medicine. Women in the precontemplation/relapse stage were most likely to report that they did not know where to get screened and that their partner would not want them to be screened. . Perceived benefits and barriers to screening were differentially associated with the stages of change. Results may support culturally sensitive and theory-based programs to improve screening rates among Chinese American women. . The results suggest the importance of cultural sensitivity among nursing providers when working with Chinese Americans to provide more relevant, holistic care.
Aziato, Lydia; Dedey, Florence; Clegg-Lamptey, Joe Nat A
2014-07-26
Dysmenorrhoea is a common problem of women at the reproductive age and may have negative effect on the education of females at various stages on the educational ladder. This study sought to gain an in-depth understanding of the experience of dysmenorrhoea and its effect on female students in a secondary and a tertiary institution in Accra, Ghana. The study employed a descriptive phenomenology design and was conducted at a University and a Senior High School (SHS) in Accra. Purposive and snowball sampling techniques were used to recruit participants and data was saturated with 16 participants. Concurrent analysis was done by applying the processes of content analysis and the NVivo software was used to manage the data. It was realized that dysmenorrhoea is associated with symptoms such as diarrhoea, headache and vomiting. Pain may start one week to the day of menstruation and the severity differed across the days of menstruation. The effect of dysmenorrhoea included activity intolerance, altered emotion and interaction, altered sleep pattern, absenteeism and inattentiveness, wishes and regrets, and misconceptions. It was concluded that severe dysmenorrhoea has a debilitating effect on female students and is associated with misconceptions that could result in drastic action with fatal consequences. Thus, there is the need to enhance education on dysmenorrhoea, and an aggressive step should be taken to effectively manage dysmenorrhoea.
2014-01-01
Background Dysmenorrhoea is a common problem of women at the reproductive age and may have negative effect on the education of females at various stages on the educational ladder. Context and purpose This study sought to gain an in-depth understanding of the experience of dysmenorrhoea and its effect on female students in a secondary and a tertiary institution in Accra, Ghana. Methods The study employed a descriptive phenomenology design and was conducted at a University and a Senior High School (SHS) in Accra. Purposive and snowball sampling techniques were used to recruit participants and data was saturated with 16 participants. Concurrent analysis was done by applying the processes of content analysis and the NVivo software was used to manage the data. Results It was realized that dysmenorrhoea is associated with symptoms such as diarrhoea, headache and vomiting. Pain may start one week to the day of menstruation and the severity differed across the days of menstruation. The effect of dysmenorrhoea included activity intolerance, altered emotion and interaction, altered sleep pattern, absenteeism and inattentiveness, wishes and regrets, and misconceptions. Conclusions It was concluded that severe dysmenorrhoea has a debilitating effect on female students and is associated with misconceptions that could result in drastic action with fatal consequences. Thus, there is the need to enhance education on dysmenorrhoea, and an aggressive step should be taken to effectively manage dysmenorrhoea. PMID:25064081
[Fibromyalgia patients' perceptions of the impact of the disease in the workplace].
Briones-Vozmediano, Erica; Ronda-Pérez, Elena; Vives-Cases, Carmen
2015-04-01
To explore the perceptions of patients with fibromyalgia (FM) on the problems they experience in the workplace, to discuss how they face and adapt to the limitations imposed by the symptoms of this disease. An exploratory qualitative study conducted in 2009. Associations of patients of FM from Valencia (Spain). Sixteen patients (13 women and 3 men) diagnosed with FM by a rheumatologist, of different ages and occupations, selected from key informants and the snowball technique. Pragmatic sample. Semi-structured interviews until saturation of information when no new information emerged. Qualitative content analysis using the software Atlas.ti-5, to generate and assign codes, forming categories and identifying a latent theme. We identified four categories: difficulties in meeting the work demands, need for social support in the workplace, strategies adopted to continue working, and resistance to leave the employment. A theme which crosscut these categories emerged: FM patientś motivation to continue in the labour market. Addressing the specific needs of patients it is essential in order to helping them to stay in the labour market, according to their capabilities. Awareness programs about the consequences of FM in the workplace are needed to achieve the collaboration of managers, entrepreneurs, occupational health professionals and primary care physicians and nurses. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.
Social accountability and nursing education in South Africa.
Armstrong, Susan J; Rispel, Laetitia C
2015-01-01
There is global emphasis on transforming health workforce education in support of universal health coverage. This paper uses a social accountability framework, specifically the World Health Organization's six building blocks for transformative education, to explore key informants' perspectives on nursing education in South Africa. Using a snowballing sampling technique, 44 key informants were selected purposively on the basis of their expertise or knowledge of the research area. Semi-structured interviews were conducted with the key informants after informed consent had been obtained. The interviews were analysed using template analysis. South Africa has strategic plans on human resources for health and nursing education, training, and practice and has a well-established system of regulation and accreditation of nursing education through the South African Nursing Council (SANC). Key informants criticised the following: the lack of national staffing norms; sub-optimal governance by both the SANC and the Department of Health; outdated curricula that are unresponsive to population and health system needs; lack of preparedness of nurse educators; and the unsuitability of the majority of nursing students. These problems are exacerbated by a perceived lack of prioritisation of nursing, resource constraints in both the nursing education institutions and the health training facilities, and general implementation inertia. Social accountability, which is an essential component of transformative education, necessitates that attention be paid to the issues of governance, responsive curricula, educator preparedness, and appropriate student recruitment and selection.
Ecstasy (MDMA): effects and patterns of use reported by users in São Paulo.
de Almeida, Stella Pereira; Silva, Maria Teresa Araujo
2003-03-01
As there are no studies about the use of ecstasy in Brazil, our aim was to identify the effects and patterns of use of this substance among users in the city of São Paulo. Subjects were recruited through the snowball technique. Fifty-two subjects of both genders who had been using ecstasy frequently and recently were interviewed. The instrument was a self-reported and anonymous questionnaire. The sample's mean age was 24 years, mostly composed by single, college graduated middle-class subjects. Among the interviewed users, 61.6% used ecstasy at least once per week and 50% of them took one pill per episode of use and 46% more than one. Drug taking was usually performed in company of several people (63%) in contexts related to night leisure, such as rave parties (78.8%), dancing clubs (69.2%) and parties (53.8%). Ecstasy pills were mainly purchased from friends or acquaintances in order to favor a dancing mood in those places. Most subjects used ecstasy associated to other psychoactive drugs (93.3%), mainly Cannabis, followed by tobacco and LSD. The effects attributed to ecstasy were mainly positive. The use of ecstasy in São Paulo has had a recreational pattern quite similar to those described in previous studies. The assessment of the use of ecstasy as positive also agrees with the findings of the literature.
2013-01-01
Background Ethnobotanical studies on the use of plants amongst migrant populations are of great relevance to public health. Traditional health strategies, which incorporate plants as medicines, foods, or both – can play an important role in individual well-being. However, at the same time, migrant populations’ traditional knowledge of such practices may be under a state of greater threat of decline due to factors such as limited access to the plant materials and physical isolation from the homeland, which serves as the primary living reservoir for this knowledge. Methods In this study, we conducted a medical ethnobotanical survey focusing on a comparison of local medicinal food and health strategies with members of two Asian immigrant populations in metro-Atlanta: Chinese and Taiwanese. Snowball sampling techniques were employed to recruit 83 study participants, 57 of which were included in the final analysis. Semi-structured interview techniques were used to question participants about their beliefs and usage of the yin yang system, usage of Chinese herbs and medicinal foods, preference and usage of Eastern and Western medicines, and gardening for medicinal foods. Results and conclusion Comparison of the two groups demonstrated a remarkable difference in health strategies concerning medicinal plant use, including statistically significant differences in beliefs concerning yin and yang, uses of Eastern versus Western medicine, and gardening for medicinal foods. Domestic health strategies in the form of medicinal foods play an important role in local health practices, especially among the Taiwanese participants. The collective desire for the use of both Eastern and Western medicine by both groups highlights the important role that cultural competency training will play in preparing allopathic health practitioners to serve increasingly diverse patient populations in the US. PMID:23981857
Lans, Cheryl
2007-01-01
This paper provides a preliminary evaluation of fifty-eight ethnomedicinal plants used in Trinidad and Tobago for skin problems, stomach problems, pain and internal parasites for safety and possible efficacy. Thirty respondents, ten of whom were male were interviewed from September 1996 to September 2000 on medicinal plant use for health problems. The respondents were obtained by snowball sampling, and were found in thirteen different sites, 12 in Trinidad and one in Tobago. The uses are compared to those current in Asia. Bambusa vulgaris, Bidens alba, Jatropha curcas, Neurolaena lobata, Peperomia rotundifolia and Phyllanthus urinaria are possibly efficacous for stomach problems, pain and internal parasites. Further scientific study of these plants is warranted. PMID:17207273
Lans, Cheryl
2007-01-05
This paper provides a preliminary evaluation of fifty-eight ethnomedicinal plants used in Trinidad and Tobago for skin problems, stomach problems, pain and internal parasites for safety and possible efficacy. Thirty respondents, ten of whom were male were interviewed from September 1996 to September 2000 on medicinal plant use for health problems. The respondents were obtained by snowball sampling, and were found in thirteen different sites, 12 in Trinidad and one in Tobago. The uses are compared to those current in Asia. Bambusa vulgaris, Bidens alba, Jatropha curcas, Neurolaena lobata, Peperomia rotundifolia and Phyllanthus urinaria are possibly efficacious for stomach problems, pain and internal parasites. Further scientific study of these plants is warranted.
Gibson, Crystal; Perley, Lauren; Bailey, Jonathan; Barbour, Russell; Kershaw, Trace
2015-01-01
Social network and area level characteristics have been linked to substance use. We used snowball sampling to recruit 90 predominantly African American emerging adult men who provided typical locations visited (n=510). We used generalized estimating equations to examine social network and area level predictors of substance use. Lower social network quality was associated with days of marijuana use (B=-0.0037, p<0.0001) and problem alcohol use (B=-0.0050, p=0.0181). The influence of area characteristics on substance use differed between risky and non-risky spaces. Peer and area influences are important for substance use among men, and may differ for high and low risk places. PMID:26176810
Palliative care and the intensive care nurses: feelings that endure.
Silveira, Natyele Rippel; Nascimento, Eliane Regina Pereira do; Rosa, Luciana Martins da; Jung, Walnice; Martins, Sabrina Regina; Fontes, Moisés Dos Santos
2016-01-01
to know the feelings of nurses regarding palliative care in adult intensive care units. qualitative study, which adopted the theoretical framework of Social Representations, carried out with 30 nurses of the state of Santa Catarina included by Snowball sampling. Data were collected through semi-structured interviews conducted from April to August 2015, organized and analyzed through the Collective Subject Discourse. the results showed how central ideas are related to feelings of comfort, frustration, insecurity and anguish, in addition to the feeling that the professional training and performance are focused on the cure. the social representations of nurses regarding the feelings related to palliative care are represented mainly by negative feelings, probably as consequence of the context in which care is provided.
Positive Ion Induced Solidification of He4
NASA Astrophysics Data System (ADS)
Moroshkin, P.; Lebedev, V.; Weis, A.
2009-03-01
We have observed bulk solidification of He4 induced by nucleation on positive alkali ions in pressurized superfluid helium. The ions are extracted into the liquid from alkali-doped solid He by a static electric field. The experiments prove the existence of charged particles in a solid structure composed of doped He that was recently shown to coexist with superfluid helium below the He solidification pressure. This supports our earlier suggestion that the Coulomb interaction of positive ions surrounded by a solid He shell (snowballs) and electrons trapped in spherical cavities (electron bubbles), together with surface tension, is responsible for the stability of that structure against melting. We have determined the density of charges in the sample by two independent methods.
Addressing the Needs of Transgender Military Veterans: Better Access and More Comprehensive Care
Dietert, Michelle; Dentice, Dianne; Keig, Zander
2017-01-01
Abstract Purpose: There is a gap in social science literature addressing issues of access and quality of care for transgender military veterans. Psychologists, medical doctors, and other health professionals are beginning to address some of the barriers present in the Department of Veterans Affairs (VA) system that affect veterans who are also transgender and intersex. Over a 7-year period, between 2006 and 2013, 2600 transgender veterans were served by the VA. Data from several surveys revealed that most transgender veterans perceive the Veterans Health Administration (VHA) to be less than accommodating for their special needs. The goal of this study was to investigate the experiences of a sample of transgender veterans with regard to their experiences with healthcare services provided by the VHA. Methods: Using snowball sampling techniques, we were able to recruit 22 transgender military veterans to participate in our study. A combination of telephone interviews and questionnaires provided data from veterans in various branches of the military throughout the United States. Results: Findings indicate that even though the VHA is working to address issues of inequality for transgender veterans, our participants indicated that there are still some problems with administration of care, proper training of staff and physicians, and availability of comprehensive services for the unique healthcare needs of transgender individuals. Conclusion: Since our data were collected, the VA has worked to bridge the gap by focusing on increased training for VHA providers and staff and establishing LGBT programs at VA facilities. However, we suggest that one key area of importance should continue to focus on how mental health and medical providers and ancillary staff are trained to interact with and provide care for their transgender patients. PMID:28861546
Gibbs, Lisa; Waters, Elizabeth; de Silva, Andrea; Riggs, Elisha; Moore, Laurence; Armit, Christine; Johnson, Britt; Morris, Michal; Calache, Hanny; Gussy, Mark; Young, Dana; Tadic, Maryanne; Christian, Bradley; Gondal, Iqbal; Watt, Richard; Pradel, Veronika; Truong, Mandy; Gold, Lisa
2014-01-01
Introduction Inequalities are evident in early childhood caries rates with the socially disadvantaged experiencing greater burden of disease. This study builds on formative qualitative research, conducted in the Moreland/Hume local government areas of Melbourne, Victoria 2006–2009, in response to community concerns for oral health of children from refugee and migrant backgrounds. Development of the community-based intervention described here extends the partnership approach to cogeneration of contemporary evidence with continued and meaningful involvement of investigators, community, cultural and government partners. This trial aims to establish a model for child oral health promotion for culturally diverse communities in Australia. Methods and analysis This is an exploratory trial implementing a community-based child oral health promotion intervention for Australian families from refugee and migrant backgrounds. Families from an Iraqi, Lebanese or Pakistani background with children aged 1–4 years, residing in metropolitan Melbourne, were invited to participate in the trial by peer educators from their respective communities using snowball and purposive sampling techniques. Target sample size was 600. Moreland, a culturally diverse, inner-urban metropolitan area of Melbourne, was chosen as the intervention site. The intervention comprised peer educator led community oral health education sessions and reorienting of dental health and family services through cultural Competency Organisational Review (CORe). Ethics and dissemination Ethics approval for this trial was granted by the University of Melbourne Human Research Ethics Committee and the Department of Education and Early Childhood Development Research Committee. Study progress and output will be disseminated via periodic newsletters, peer-reviewed research papers, reports, community seminars and at National and International conferences. Trial registration number Australian New Zealand Clinical Trials Registry (ACTRN12611000532909). PMID:24622949
Rock, Adam J; Permezel, Fiona E; Storm, Lance
2012-01-01
Previous research has demonstrated the effects of ostensible subtle energy on physical systems and subjective experience. However, one subtle energy technique that has been neglected, despite anecdotal support for its efficacy, is Quantum BioEnergetics (QBE). Furthermore, the influence of paranormal belief and experience (either real belief/experience or suggested belief/experience) on subtle energy effects remains unclear. The aim of the present study was to investigate experimentally the effects of distant QBE healing, and paranormal belief/experience, on mood. A randomized expectancy-enhanced placebo-controlled design was used. Data were collected at the QBE Centre, Melbourne. Participants were students from Deakin University and from the general public. Snowball sampling (ie, word-of-mouth) and convenience sampling using a ballot box placed in the university library. Profile of Mood States-Short Form was used to quantify positive and negative mood states. The QBE condition was associated with (1) significantly less Tension-Anxiety compared with the placebo and control condition; and (2) significantly less Anger-Hostility and Total Mood Disturbance compared with the control condition (but not the placebo condition). Furthermore, there was an interaction of condition and paranormal belief/experience with regard to Depression-Dejection, with believers assigned to the placebo condition scoring lowest on this Mood variable. Findings suggest that the use of QBE by an experienced practitioner reduces mood disturbance. In addition, the placebo condition may have evoked suggestibility effects in believers, which would mean that they may be more likely than nonbelievers to believe that they were receiving healing, thus resulting in lower Depression-Dejection scores. Copyright © 2012 Elsevier Inc. All rights reserved.
Addressing the Needs of Transgender Military Veterans: Better Access and More Comprehensive Care.
Dietert, Michelle; Dentice, Dianne; Keig, Zander
2017-01-01
Purpose: There is a gap in social science literature addressing issues of access and quality of care for transgender military veterans. Psychologists, medical doctors, and other health professionals are beginning to address some of the barriers present in the Department of Veterans Affairs (VA) system that affect veterans who are also transgender and intersex. Over a 7-year period, between 2006 and 2013, 2600 transgender veterans were served by the VA. Data from several surveys revealed that most transgender veterans perceive the Veterans Health Administration (VHA) to be less than accommodating for their special needs. The goal of this study was to investigate the experiences of a sample of transgender veterans with regard to their experiences with healthcare services provided by the VHA. Methods: Using snowball sampling techniques, we were able to recruit 22 transgender military veterans to participate in our study. A combination of telephone interviews and questionnaires provided data from veterans in various branches of the military throughout the United States. Results: Findings indicate that even though the VHA is working to address issues of inequality for transgender veterans, our participants indicated that there are still some problems with administration of care, proper training of staff and physicians, and availability of comprehensive services for the unique healthcare needs of transgender individuals. Conclusion: Since our data were collected, the VA has worked to bridge the gap by focusing on increased training for VHA providers and staff and establishing LGBT programs at VA facilities. However, we suggest that one key area of importance should continue to focus on how mental health and medical providers and ancillary staff are trained to interact with and provide care for their transgender patients.
Gibbs, Lisa; Waters, Elizabeth; de Silva, Andrea; Riggs, Elisha; Moore, Laurence; Armit, Christine; Johnson, Britt; Morris, Michal; Calache, Hanny; Gussy, Mark; Young, Dana; Tadic, Maryanne; Christian, Bradley; Gondal, Iqbal; Watt, Richard; Pradel, Veronika; Truong, Mandy; Gold, Lisa
2014-03-12
Inequalities are evident in early childhood caries rates with the socially disadvantaged experiencing greater burden of disease. This study builds on formative qualitative research, conducted in the Moreland/Hume local government areas of Melbourne, Victoria 2006-2009, in response to community concerns for oral health of children from refugee and migrant backgrounds. Development of the community-based intervention described here extends the partnership approach to cogeneration of contemporary evidence with continued and meaningful involvement of investigators, community, cultural and government partners. This trial aims to establish a model for child oral health promotion for culturally diverse communities in Australia. This is an exploratory trial implementing a community-based child oral health promotion intervention for Australian families from refugee and migrant backgrounds. Families from an Iraqi, Lebanese or Pakistani background with children aged 1-4 years, residing in metropolitan Melbourne, were invited to participate in the trial by peer educators from their respective communities using snowball and purposive sampling techniques. Target sample size was 600. Moreland, a culturally diverse, inner-urban metropolitan area of Melbourne, was chosen as the intervention site. The intervention comprised peer educator led community oral health education sessions and reorienting of dental health and family services through cultural Competency Organisational Review (CORe). Ethics approval for this trial was granted by the University of Melbourne Human Research Ethics Committee and the Department of Education and Early Childhood Development Research Committee. Study progress and output will be disseminated via periodic newsletters, peer-reviewed research papers, reports, community seminars and at National and International conferences. Australian New Zealand Clinical Trials Registry (ACTRN12611000532909).
Water/rock interactions in experimentally simulated dirty snowball and dirty iceball cometary nuclei
NASA Technical Reports Server (NTRS)
Gooding, James L.; Allton, Judith H.
1991-01-01
In the dirty snowball model for cometary nuclei, comet-nucleus materials are regarded as mixtures of volatile ices and relatively non-volatile minerals or chemical compounds. Carbonaceous chondrite meteorites are regarded as useful analogs for the rocky component. To help elucidate the possible physical geochemistry of cometary nuclei, preliminary results are reported of calorimetric experiments with two-component systems involving carbonaceous chondrites and water ice. Based on collective knowledge of the physics of water ice, three general types of interactions can be expected between water and minerals at sub-freezing temperatures: (1) heterogeneous nucleation of ice by insoluble minerals; (2) adsorption of water vapor by hygroscopic phases; and (3) freezing- and melting-point depression of liquid water sustained by soluble minerals. The relative and absolute magnitude of all three effects are expected to vary with mineral composition.
Biologically induced initiation of Neoproterozoic snowball-Earth events.
Tziperman, Eli; Halevy, Itay; Johnston, David T; Knoll, Andrew H; Schrag, Daniel P
2011-09-13
The glaciations of the Neoproterozoic Era (1,000 to 542 MyBP) were preceded by dramatically light C isotopic excursions preserved in preglacial deposits. Standard explanations of these excursions involve remineralization of isotopically light organic matter and imply strong enhancement of atmospheric CO(2) greenhouse gas concentration, apparently inconsistent with the glaciations that followed. We examine a scenario in which the isotopic signal, as well as the global glaciation, result from enhanced export of organic matter from the upper ocean into anoxic subsurface waters and sediments. The organic matter undergoes anoxic remineralization at depth via either sulfate- or iron-reducing bacteria. In both cases, this can lead to changes in carbonate alkalinity and dissolved inorganic pool that efficiently lower the atmospheric CO(2) concentration, possibly plunging Earth into an ice age. This scenario predicts enhanced deposition of calcium carbonate, the formation of siderite, and an increase in ocean pH, all of which are consistent with recent observations. Late Neoproterozoic diversification of marine eukaryotes may have facilitated the episodic enhancement of export of organic matter from the upper ocean, by causing a greater proportion of organic matter to be partitioned as particulate aggregates that can sink more efficiently, via increased cell size, biomineralization or increased CN of eukaryotic phytoplankton. The scenario explains isotopic excursions that are correlated or uncorrelated with snowball initiation, and suggests that increasing atmospheric oxygen concentrations and a progressive oxygenation of the subsurface ocean helped to prevent snowball glaciation on the Phanerozoic Earth.
NASA Astrophysics Data System (ADS)
Young, Grant M.
Paleoproterozoic glaciogenic deposits have a more restricted distribution than those of the Neoproterozoic, which are thought by some to provide evidence that the surface of the entire Earth was frozen (snowball Earth hypothesis). In Laurentia, Paleoproterozoic glacial rocks appear to be associated with the breakup of a supercontinent, whereas in Vaalbara they may form part of the early fill of compressional (foreland?) basins representing ocean closure. The scattered Paleoproterozoic glacial deposits may be approximately contemporaneous but ages are poorly constrained at around 2.3 Ga. Many features ascribed to the existence of a snowball Earth in the Neoproterozoic are not developed in the Paleoproterozoic. For example most of the older glaciogenic successions lack cap carbonates. Major element geochemistry of the post-glacial sedimentary rocks of the Gowganda Formation suggests a weathering trend opposite to that predicted by the SEH. The close association between iron-formations and some glacial deposits in the Neoproterozoic, is virtually absent from the Paleoproterozoic. Thus the Paleoproterozoic glacial successions lack many of the criteria that are supposed to substantiate the snowball Earth hypothesis. These ancient glacial deposits are perhaps more appropriately compared with those of temperate glaciations. Apparent low paleolatitudes derived from some Paleoproterozoic glaciogenic deposits pose a problem for any interpretation of these rocks. Williams suggested that these odd relationships might be explained by a much higher obliquity of the Earth's ecliptic in the Precambrian but resolution of these problems must await additional geochronological and paleomagnetic work.
Biologically induced initiation of Neoproterozoic snowball-Earth events
Tziperman, Eli; Halevy, Itay; Johnston, David T.; Knoll, Andrew H.; Schrag, Daniel P.
2011-01-01
The glaciations of the Neoproterozoic Era (1,000 to 542 MyBP) were preceded by dramatically light C isotopic excursions preserved in preglacial deposits. Standard explanations of these excursions involve remineralization of isotopically light organic matter and imply strong enhancement of atmospheric CO2 greenhouse gas concentration, apparently inconsistent with the glaciations that followed. We examine a scenario in which the isotopic signal, as well as the global glaciation, result from enhanced export of organic matter from the upper ocean into anoxic subsurface waters and sediments. The organic matter undergoes anoxic remineralization at depth via either sulfate- or iron-reducing bacteria. In both cases, this can lead to changes in carbonate alkalinity and dissolved inorganic pool that efficiently lower the atmospheric CO2 concentration, possibly plunging Earth into an ice age. This scenario predicts enhanced deposition of calcium carbonate, the formation of siderite, and an increase in ocean pH, all of which are consistent with recent observations. Late Neoproterozoic diversification of marine eukaryotes may have facilitated the episodic enhancement of export of organic matter from the upper ocean, by causing a greater proportion of organic matter to be partitioned as particulate aggregates that can sink more efficiently, via increased cell size, biomineralization or increased C∶N of eukaryotic phytoplankton. The scenario explains isotopic excursions that are correlated or uncorrelated with snowball initiation, and suggests that increasing atmospheric oxygen concentrations and a progressive oxygenation of the subsurface ocean helped to prevent snowball glaciation on the Phanerozoic Earth. PMID:21825156
Episode of intense chemical weathering during the termination of the 635 Ma Marinoan glaciation
Huang, Kang-Jun; Teng, Fang-Zhen; Shen, Bing; Xiao, Shuhai; Lang, Xianguo; Ma, Hao-Ran; Fu, Yong; Peng, Yongbo
2016-01-01
Cryogenian (∼720–635 Ma) global glaciations (the snowball Earth) represent the most extreme ice ages in Earth’s history. The termination of these snowball Earth glaciations is marked by the global precipitation of cap carbonates, which are interpreted to have been driven by intense chemical weathering on continents. However, direct geochemical evidence for the intense chemical weathering in the aftermath of snowball glaciations is lacking. Here, we report Mg isotopic data from the terminal Cryogenian or Marinoan-age Nantuo Formation and the overlying cap carbonate of the basal Doushantuo Formation in South China. A positive excursion of extremely high δ26Mg values (+0.56 to +0.95)—indicative of an episode of intense chemical weathering—occurs in the top Nantuo Formation, whereas the siliciclastic component of the overlying Doushantuo cap carbonate has significantly lower δ26Mg values (<+0.40), suggesting moderate to low intensity of chemical weathering during cap carbonate deposition. These observations suggest that cap carbonate deposition postdates the climax of chemical weathering, probably because of the suppression of carbonate precipitation in an acidified ocean when atmospheric CO2 concentration was high. Cap carbonate deposition did not occur until chemical weathering had consumed substantial amounts of atmospheric CO2 and accumulated high levels of oceanic alkalinity. Our finding confirms intense chemical weathering at the onset of deglaciation but indicates that the maximum weathering predated cap carbonate deposition. PMID:27956606
Methodology Series Module 10: Qualitative Health Research
Setia, Maninder Singh
2017-01-01
Although quantitative designs are commonly used in clinical research, some studies require qualitative methods. These designs are different from quantitative methods; thus, researchers should be aware of data collection methods and analyses for qualitative research. Qualitative methods are particularly useful to understand patient experiences with the treatment or new methods of management or to explore issues in detail. These methods are useful in social and behavioral research. In qualitative research, often, the main focus is to understand the issue in detail rather than generalizability; thus, the sampling methods commonly used are purposive sampling; quota sampling; and snowball sampling (for hard to reach groups). Data can be collected using in-depth interviews (IDIs) or focus group discussions (FGDs). IDI is a one-to-one interview with the participant. FGD is a method of group interview or discussion, in which more than one participant is interviewed at the same time and is usually led by a facilitator. The commonly used methods for data analysis are: thematic analysis; grounded theory analysis; and framework analysis. Qualitative data collection and analysis require special expertise. Hence, if the reader plans to conduct qualitative research, they should team up with a qualitative researcher. PMID:28794545
Özbek, Emel; Bongers, Ilja L; Lobbestael, Jill; van Nieuwenhuizen, Chijs
2015-12-01
This study investigated the relationship between acculturation and psychological problems in Turkish and Moroccan young adults living in the Netherlands. A sample of 131 healthy young adults aged between 18 and 24 years old, with a Turkish or Moroccan background was recruited using snowball sampling. Data on acculturation, internalizing and externalizing problems, beliefs about psychological problems, attributions of psychological problems and barriers to care were collected and analyzed using Latent Class Analysis and multinomial logistic regression. Three acculturation classes were identified in moderately to highly educated, healthy Turkish or Moroccan young adults: integration, separation and diffusion. None of the participants in the sample were marginalized or assimilated. Young adults reporting diffuse acculturation reported more internalizing and externalizing problems than those who were integrated or separated. Separated young adults reported experiencing more practical barriers to care than integrated young adults. Further research with a larger sample, including young adult migrants using mental health services, is required to improve our understanding of acculturation, psychological problems and barriers to care in this population. Including experiences of discrimination in the model might improve our understanding of the relationship between different forms of acculturation and psychological problems.
Methodology Series Module 10: Qualitative Health Research.
Setia, Maninder Singh
2017-01-01
Although quantitative designs are commonly used in clinical research, some studies require qualitative methods. These designs are different from quantitative methods; thus, researchers should be aware of data collection methods and analyses for qualitative research. Qualitative methods are particularly useful to understand patient experiences with the treatment or new methods of management or to explore issues in detail. These methods are useful in social and behavioral research. In qualitative research, often, the main focus is to understand the issue in detail rather than generalizability; thus, the sampling methods commonly used are purposive sampling; quota sampling; and snowball sampling (for hard to reach groups). Data can be collected using in-depth interviews (IDIs) or focus group discussions (FGDs). IDI is a one-to-one interview with the participant. FGD is a method of group interview or discussion, in which more than one participant is interviewed at the same time and is usually led by a facilitator. The commonly used methods for data analysis are: thematic analysis; grounded theory analysis; and framework analysis. Qualitative data collection and analysis require special expertise. Hence, if the reader plans to conduct qualitative research, they should team up with a qualitative researcher.
A National Survey of Tobacco Cessation Programs for Youths
Curry, Susan J.; Emery, Sherry; Sporer, Amy K.; Mermelstein, Robin; Flay, Brian R.; Berbaum, Michael; Warnecke, Richard B.; Johnson, Timothy; Mowery, Paul; Parsons, Jennifer; Harmon, Lori; Hund, Lisa; Wells, Henry
2007-01-01
Objectives. We collected data on a national sample of existing community-based tobacco cessation programs for youths to understand their prevalence and overall characteristics. Methods. We employed a 2-stage sampling design with US counties as the first-stage probability sampling units. We then used snowball sampling in selected counties to identify administrators of tobacco cessation programs for youths. We collected data on cessation programs when programs were identified. Results. We profiled 591 programs in 408 counties. Programs were more numerous in urban counties; fewer programs were found in low-income counties. State-level measures of smoking prevalence and tobacco control expenditures were not associated with program availability. Most programs were multisession, school-based group programs serving 50 or fewer youths per year. Program content included cognitive-behavioral components found in adult programs along with content specific to adolescence. The median annual budget was $2000. Few programs (9%) reported only mandatory enrollment, 35% reported mixed mandatory and voluntary enrollment, and 56% reported only voluntary enrollment. Conclusions. There is considerable homogeneity among community-based tobacco cessation programs for youths. Programs are least prevalent in the types of communities for which national data show increases in youths’ smoking prevalence. PMID:17138932
2010-11-18
Icy particles in the cloud around Hartley 2, as seen by NASA EPOXI mission spacecraft. A star moving through the background is marked with red and moves in a particular direction, with a particular speed; icy particles move in random directions.
Middleton, A; Bragin, E; Parker, M
2014-10-01
This paper offers a description of how social media, traditional media and direct invitation were used as tools for the recruitment of 6,944 research participants for a social sciences study on genomics. The remit was to gather the views of various stakeholders towards sharing incidental findings from whole genome studies. This involved recruiting members of the public, genetic health professionals, genomic researchers and non-genetic health professionals. A novel survey was designed that contained ten integrated films; this was made available online and open for completion by anyone worldwide. The recruitment methods are described together with the convenience and snowballing sampling framework. The most successful strategy involved the utilisation of social media; Facebook, Blogging, Twitter, LinkedIn and Google Ads led to the ascertainment of over 75 % of the final sample. We conclude that the strategies used were successful in recruiting in eclectic mix of appropriate participants. Design of the survey and results from the study are presented separately.
Using the internet to recruit rural MSM for HIV risk assessment: sampling issues.
Bowen, Anne; Williams, Mark; Horvath, Keith
2004-09-01
The Internet is an emerging research tool that may be useful for contacting and working with rural men who have sex with men (MSM). Little is known about HIV risks for rural men and Internet methodological issues are only beginning to be examined. Internet versus conventionally recruited samples have shown both similarities and differences in their demographic characteristics. In this study, rural MSM from three sizes of town were recruited by two methods: conventional (e.g. face-to-face/snowball) or Internet. After stratifying for size of city, demographic characteristics of the two groups were similar. Both groups had ready access to the Internet. Patterns of sexual risk were similar across the city sizes but varied by recruitment approach, with the Internet group presenting a somewhat higher HIV sexual risk profile. Overall, these findings suggest the Internet provides a useful and low cost approach to recruiting and assessing HIV sexual risks for rural White MSM. Further research is needed on methods for recruiting rural minority MSM.
A prospective health impact assessment of the international astronomy and space exploration centre.
Winters, L Y
2001-06-01
Assess the potential health impacts of the proposed International Astronomy and Space Exploration Centre on the population of New Wallasey. Contribute to the piloting of health impact assessment methods. Prospective health impact assessment involving brainstorming sessions and individual interviews with key informants and a literature review. New Wallasey Single Regeneration Budget 4 area. Key stakeholders including local residents' groups selected through purposeful snowball sampling. Recommendations are made that cover issues around: transport and traffic; civic design; security; public safety, employment and training. Health impact assessment is a useful pragmatic tool for facilitating wide consultation. In particular engaging the local population in the early planning stages of a proposed development, and assisting in highlighting changes to maximise the positive health influences on affected communities.
NASA Astrophysics Data System (ADS)
Light, B.; Black, T.; Carns, R.; Brandt, R.; Dadic, R.; Warren, S.
2012-04-01
During the initial freezing of the tropical ocean on Snowball Earth, the first ice to form would be sea ice, which contains salt within liquid brine inclusions. At temperatures below -23 C, significant amounts of salt begin to crystallize within the brine inclusions. These crystals scatter light, increasing the ice albedo. The most abundant salt is hydrohalite, NaCl.2H2O. A dry tropical atmosphere promoting ice surface sublimation would cause a salt crust to be left on the surface as a lag deposit. Such a high-albedo surface could be crucial during the snowball initiation. These processes must be considered when assigning albedos to sea ice in a climate model of Snowball Earth. Precipitation of salt within brine inclusions was observed on windswept bare ice of McMurdo Sound at the coast of Antarctica (78 S) in late winter. Consequently the albedo was higher at lower temperature. The precipitation process exhibited hysteresis, with hydrohalite precipitating at about -30 C and dissolving at about -23 C. The causes of the hysteresis are being investigated in laboratory experiments; they may involve biological macromolecules. Nowhere on the modern Earth does sea ice undergo sublimation at low temperatures for long enough to develop a salt crust before the summer melt begins, so this process is being investigated in our laboratory. A 1000-liter tank is used to grow artificial sea ice, and a system has been built to measure its albedo. A diffusely reflecting hemispherical dome of diameter 1.2 m is placed on top of the tank and illuminated from within. The interior of the dome illuminates the ice surface as well as serving as a platform for detecting the incident and backscattered radiance fields. The diffusely reflecting surfaces of the ice and the dome make it straightforward to estimate incoming and reflected irradiance as angular integrals of the radiance measurements. The albedo of the bare, cold (below -23 C) ice is 0.8 at visible wavelengths, decreasing toward the near-infrared but remaining higher than that of warmer ice. The salt crust has very high albedo, >0.9 for wavelengths 300-1000 nm, and remains much higher than snow across the near-infrared. Halite (NaCl) is nonabsorptive throughout the solar spectrum, but the hydrohalite crust contains two waters of hydration and does show water-absorption features at 1500 and 2000 nm, as expected. When the crust was warmed to -20 C, saline puddles formed and the albedo dropped dramatically. The spectral albedos are integrated over wavelength, using a solar spectrum appropriate for the tropical snowball ocean, to obtain broadband albedos. Preliminary values for the broadband albedos are 0.89 for the salt crust, 0.56 for bare subeutectic ice without a crust, and 0.32 for puddled melting ice.
Hauck, Yvonne L; Blixt, Ingrid; Hildingsson, Ingegerd; Gallagher, Louise; Rubertsson, Christine; Thomson, Brooke; Lewis, Lucy
2016-10-10
Breastfeeding initiation rates in some developed countries are high (98 % in Sweden and 96 % in Australia) whereas in others, they are not as favourable (46 % to 55 % in Ireland). Although the World Health Organization recommends exclusively breastfeeding for six months, 15 % of Australian women, 11 % of Swedish women and less than 7 % of Irish women achieve this goal. Awareness of what women in different countries perceive as essential breastfeeding support is a gap in our knowledge. Our aim was to explore Australian, Irish and Swedish women's perceptions of what assisted them to continue breastfeeding for six months. An exploratory design using critical incident techniques was used. Recruitment occurred through advertisements in local newspapers and on social networking platforms. Initial sampling was purposive, followed by snowball sampling. Telephone interviews were conducted with 64 Irish, 139 Swedish and 153 Australian women who responded to one question "what has assisted you to continue breastfeeding for at least six months?" Content analysis was conducted and common categories determined to allow comparison of frequencies and priority ranking. Categories reflected the individual mother, her inner social network, her outer social network (informal support either face to face or online), and societal support (health professionals, work environment and breastfeeding being regarded as the cultural norm). Categories ranked in the top five across the three countries were 'informal face to face support' and 'maternal determination'. Swedish and Australian women ranked "health professional support" higher (first and third respectively) than Irish women who ranked 'informal online support' as second compared to ninth and tenth for Swedish and Australian women. The support required to assist breastfeeding women is complex and multi-faceted. Although common international categories were revealed, the ranking of these supportive categories varied. We must recognize how the cultural context of breastfeeding support can vary for women in differing countries and acknowledge the resourcefulness of women who embrace innovations such as social media where face to face formal and informal support are not as accessible.
How tobacco companies have used package quantity for consumer targeting.
Persoskie, Alexander; Donaldson, Elisabeth A; Ryant, Chase
2018-05-31
Package quantity refers to the number of cigarettes or amount of other tobacco product in a package. Many countries restrict minimum cigarette package quantities to avoid low-cost packs that may lower barriers to youth smoking. We reviewed Truth Tobacco Industry Documents to understand tobacco companies' rationales for introducing new package quantities, including companies' expectations and research regarding how package quantity may influence consumer behaviour. A snowball sampling method (phase 1), a static search string (phase 2) and a follow-up snowball search (phase 3) identified 216 documents, mostly from the 1980s and 1990s, concerning cigarettes (200), roll-your-own tobacco (9), smokeless tobacco (6) and 'smokeless cigarettes' (1). Companies introduced small and large packages to motivate brand-switching and continued use among current users when faced with low market share or threats such as tax-induced price increases or competitors' use of price promotions. Companies developed and evaluated package quantities for specific brands and consumer segments. Large packages offered value-for-money and matched long-term, heavy users' consumption rates. Small packages were cheaper, matched consumption rates of newer and lighter users, and increased products' novelty, ease of carrying and perceived freshness. Some users also preferred small packages as a way to try to limit consumption or quit. Industry documents speculated about many potential effects of package quantity on appeal and use, depending on brand and consumer segment. The search was non-exhaustive, and we could not assess the quality of much of the research or other information on which the documents relied. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Migration of air bubbles in ice under a temperature gradient, with application to “Snowball Earth”
NASA Astrophysics Data System (ADS)
Dadic, Ruzica; Light, Bonnie; Warren, Stephen G.
2010-09-01
To help characterize the albedo of "sea glaciers" on Snowball Earth, a study of the migration rates of air bubbles in freshwater ice under a temperature gradient was carried out in the laboratory. The migration rates of air bubbles in both natural glacier ice and laboratory-grown ice were measured for temperatures between -36°C and -4°C and for bubble diameters of 23-2000 μm. The glacier ice was sampled from a depth near close-off (74 m) in the JEMS2 ice core from Summit, Greenland. Migration rates were measured by positioning thick sections of ice on a temperature gradient stage mounted on a microscope inside a freezer laboratory. The maximum and minimum migration rates were 5.45 μm h-1 (K cm-1)-1 at -4°C and 0.03 μm h-1 (K cm-1)-1 at -36°C. Besides a strong dependence on temperature, migration rates were found to be proportional to bubble size. We think that this is due to the internal air pressure within the bubbles, which may correlate with time since close-off and therefore with bubble size. Migration rates show no significant dependence on bubble shape. Estimates of migration rates computed as a function of bubble depth within sea glaciers indicate that the rates would be low relative to the predicted sublimation rates, such that the ice surface would not lose its air bubbles to net downward migration. It is therefore unlikely that air bubble migration could outrun the advancing sublimation front, transforming glacial ice to a nearly bubble-free ice type, analogous to low-albedo marine ice.
NASA Astrophysics Data System (ADS)
Hofmann, M.; Linnemann, U.; Rai, V.; Becker, S.; Gärtner, A.; Sagawe, A.
2011-04-01
The palaeogeographic position of South China in relation to India in the Neoproterozoic is controversial. Resolution of this controversy constrains the reconstruction of Rodinia during its breakup and contributes to our understanding of Snowball Earth. This work compares the Neoproterozoic histories of the Lesser Himalaya in northern India and the Yangtze block in southern China. We present U-Pb LA-ICP-MS ages of detrital zircon grains from six Indian and three Chinese siliciclastic sedimentary rocks, such as sandstones or diamictites/tillites. In total, 1148 grains were analysed from which 833 measurements gave ages with a degree of concordance between 90 and 110%. The correlation of the Indian and the Chinese sections is possible using the tillites of both areas purportedly deposited during the Snowball Earth time interval: the Blaini tillite from India and the Nantuo tillite from China. The U-Pb ages confirm the Marinoan age of the Chinese Liantuo tillite. Although the youngest zircon age for the Indian Blaini tillite is about 678 Ma, the Marinoan age is indicated by the presence of a typical Marinoan white to bright yellowish overlying cap carbonate. In addition to the tillites, representative detrital zircon ages from over- and underlying clastic rocks were determined. The Chinese samples are dominated by zircons with Neoproterozoic ages with a main peak between ca. 750 Ma and ca. 950 Ma and are characterised by the absence of Archaean ages. The Indian samples contain abundant Neoproterozoic zircon grains, but also contain Mesoproterozoic to Archaean zircons. For all samples, a local source area that provided the Neoproterozoic zircons is likely. A synchronous Neoproterozoic magmatic event in both cratons probably reflects the breakup of the supercontinent Rodinia and therefore the same tectono-magmatic event. Our results indicate a similar history for India and South China which both underwent at least one synchronous episode of crustal growth during the Neoproterozoic. In addition, our data set shows that both passive margin clastic sequences had the same source area for all zircons older than Neoproterozoic. Therefore we infer that India and South China were close to each other and along the same passive margin during the breakup of Rodinia in the Late Neoproterozoic.
Production and characterization of micron-sized filaments of solid argon
NASA Astrophysics Data System (ADS)
Grams, Michael; Stasicki, Boleslaw; Toennies, J. Peter
2005-12-01
A continuous 50-μm-diam filament of solid argon is produced in a moderate vacuum (4.2×10-3mbar) by cooling argon gas to 70-90K over the last 8mm of a long fused silica capillary. Prior to formation of the straight filament the jet shows different stages characterized by spraying, snowballing, or spiraling filaments as documented by charge-coupled device (CCD) camera microscope pictures. Consecutive CCD pictures are used to measure the filament velocities, which increase with the driving gas pressure P0 up to about 4.0cm/s at P0=400bars with an intermediate peak at about 80bars. This technique may find applications for producing wall-less cryogenic matrices, targets for laser plasma sources of extreme UV and soft-x-ray sources, plasma implosion experiments, or H2 pellets for injection into fusion reactors.
The influence of capitalism on the production of knowledge in nursing.
Lino, Monica Motta; Backes, Vânia Marli Schubert; Costa, Maria Arminda da Silva Mendes Carneiro da; Martins, Maria Manuela Ferreira Pereira da Silva; Lino, Murielk Motta
2017-06-26
To understand the capitalist influence over the production of nursing knowledge according to Brazilian and Portuguese researchers. Descriptive, exploratory, and qualitative research, with 17 research nurses selected using the snowball technique. Data were collected from October 2011 to November 2012 in Brazil and Portugal, by means of semi-structured interviews. We analysed the content of the interviews and produced inferences based in the theoretical assumptions of Gaston Bachelard and the notion of an epistemological obstacle. The results were organised into three categories: Blocks to creativity/innovation and the practice of repetition; Overestimation of the quantitative; and Resistance to rupture. It is necessary to create new ways of assessing scientific literature from a qualitative perspective that allows room for creativity, professional development, and critical and reflective thinking. Solidarity is perceived as an alternative to overcoming the problems caused by the capitalist way of producing knowledge.
Successful ageing by whose definition? Views of older, spiritually affiliated women.
McCann Mortimer, Patricia; Ward, Lynn; Winefield, Helen
2008-12-01
Researchers have pointed to significant omissions in Rowe and Kahn's model of successful ageing and their lack of consultation with older people. This study examined late mid-life and older women's views of successful ageing. In-depth interviews were conducted with 14 women aged 60-89 years. Participants who identified themselves as spiritual and religious, or spiritual only and not religious, were recruited using the 'snowball technique'. Thematic analyses were conducted within an Interpretive Phenomenological Analysis framework. Participants described multiple dimensions of successful ageing with 15 subthemes grouped into three overarching categories of personal agency, social value and quality of life/quality of death. Participants' multidimensional views of successful ageing were broader than Rowe and Kahn's model and included the need to have a degree of autonomy over the place and manner of the last phase of life and final days (successful dying).
NASA Technical Reports Server (NTRS)
Pavlov, Alexander A.
2011-01-01
In its motion through the Milky Way galaxy, the solar system encounters an average density (>=330 H atoms/cubic cm) giant molecular cloud (GMC) approximately every 108 years, a dense (approx 2 x 103 H atoms/cubic cm) GMC every approx 109 years and will inevitably encounter them in the future. However, there have been no studies linking such events with severe (snowball) glaciations in Earth history. Here we show that dramatic climate change can be caused by interstellar dust accumulating in Earth's atmosphere during the solar system's immersion into a dense (approx ,2 x 103 H atoms/cubic cm) GMC. The stratospheric dust layer from such interstellar particles could provide enough radiative forcing to trigger the runaway ice-albedo feedback that results in global snowball glaciations. We also demonstrate that more frequent collisions with less dense GMCs could cause moderate ice ages.
Pesut, Barbara; Reimer-Kirkham, Sheryl
2010-07-01
Despite increasingly diverse, globalized societies, little attention has been paid to the influence of religious and spiritual diversity on clinical encounters within healthcare. The purpose of the study was to analyze the negotiation of religious and spiritual plurality in clinical encounters, and the social, gendered, cultural, historical, economic and political contexts that shape that negotiation. Qualitative: critical ethnography. The study was conducted in Western Canada between 2006 and 2009. Data collection occurred on palliative, hospice, medical and renal in-patient units at two tertiary level hospitals and seven community hospitals. Participants were recruited through purposive sampling and snowball technique. Twenty healthcare professionals, seventeen spiritual care providers, sixteen patients and families and twelve administrators, representing diverse ethnicities and religious affiliations, took part in the study. Data collection included 65 in-depth interviews and over 150h of participant observation. Clinical encounters between care providers and recipients were shaped by how individual identities in relation to religion and spirituality were constructed. Importantly, these identities did not occur in isolation from other lines of social classification such as gender, race, and class. Negotiating difference was a process of seeing spirituality as a point of connection, eliciting the meaning systems of patients and creating safe spaces for the expression of that meaning. The complexity of religious and spiritual identity construction and negotiation raises important questions about language and about professional competence and boundaries in clinical encounters where religion and spirituality are relevant concerns. Copyright 2009 Elsevier Ltd. All rights reserved.
Mehrtak, Mohammad; Farzaneh, Esmaeil; Habibzadeh, Shahram; Kamran, Aziz; Zandian, Hamed; Mahdavi, Abdollah
2017-01-01
Background Developing and guiding new knowledge are futile unless the organizational culture can also be transformed. Future leaders cannot emerge out of an organizational environment that is not conducive to the accumulation of experiences. Objective The aim of this study was to explore the role of organizational culture in creating a succession-planning system at the Ministry of Health and Medical Education in 2014. Methods The present qualitative framework analysis held interviews with 23 director generals, administrative directors and deputies from the headquarters of the Iranian Ministry of Health and Medical Education in 2014 who were selected through snowball sampling. The data obtained were analyzed in MAXQDA-10. Codes were extracted using inductive techniques. Results The cultural factors affecting succession-planning at the Ministry of Health and Medical Education were identified and classified under three main areas, including the cultural factors related to the directors with four themes (Directors’ job security, Constructive competition, Transparency and trust development, Creating opportunities), to the personnel with four themes (Organizational identity and loyalty, Trust in the organization, Talent and merit, Peer envy) and to the system with two themes (Values and beliefs, Politicization). Conclusion Findings of the study show that establishment and institutionalization of the succession planning to the Ministry of Health and Medical Education is deeply affected by the components of organizational culture. Accordingly, unprofessional organization culture can deprive the organization of numerous advantages in multiple-succession planning. PMID:29403623
Alm Pfrunder, A; Falk, A; Vicente, V; Lindström, V
2018-04-20
To explore the strategies of nurses working in the ambulance service while caring for patients with limited Swedish-English proficiency. Communication difficulties due to lack of mutual language is a challenge in health care systems around the world. Little is known about nurses' strategies while caring for patients with whom they do not share a mutual language in an unstructured, unplanned prehospital emergency environment, the ambulance service. A qualitative study design based on interviews was used and a purposeful sample and snowball technique was used to identify nurses with prehospital emergency experience of caring for patients with limited Swedish-English proficiency. Eleven nurses were interviewed, and the main strategy they used was adapting to the patients' need and the caring situation. The nurses used their own body, and tone of voice for creating a sense of trust and security. The nurses also used structured assessment in accordance with medical guidelines. Translation devices and relatives/bystanders were used as interpreters when possible. Another strategy was to transport the patient directly to the emergency department since they had not found a secure way of assessing and caring for the patients in the ambulance. The nurses used a palette of strategies while assessing and caring for patients when there was no mutual language between the caregiver and care seeker. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Kiran, D; Manjunath, R; Aswin K, K; Patil, Bk; Mahabalaraju, Dk
2011-01-01
Among the sexual minority groups, the Men who have Sex with Men (MSM) community is a large and scattered network. Sexual activity among MSM is frequent and often unplanned. STI and HIV are major medical problems faced by this vulnerable group. Stigma and discrimination towards this group result in poor access to preventive services that encourage condom and lubricant usage. A cross-sectional, community-based study of 309 MSM was carried out in the Davangere district between December 2008 and February 2010. Participants were identified in three stages: cruising venue identification and mapping; determining eligibility and willingness to participate; and recruitment to the study. Consecutive sampling was used to recruit the participants with the help of a snowball technique, obtaining informed and written consent. Of the participants 79.61% and 88.03% reported inconsistent use of condom and lubricant during the three months prior to the interview, respectively. In multivariate analysis, middle socioeconomic class, sex in a public place and increased frequency of sex were significantly associated with inconsistent condom use. Whereas, practising both types of anal sex (receptive and insertive), not using a condom during the last sexual encounter and increased frequency of sex were significantly associated with inconsistent lubricant use. Many social and behavioural factors are involved in the inconsistent use of condom and lubricant among MSM. Preventive programmes must identify these factors in order to target consistent condom and lubricant use among the MSM community.
Mehrtak, Mohammad; Farzaneh, Esmaeil; Habibzadeh, Shahram; Kamran, Aziz; Zandian, Hamed; Mahdavi, Abdollah
2017-11-01
Developing and guiding new knowledge are futile unless the organizational culture can also be transformed. Future leaders cannot emerge out of an organizational environment that is not conducive to the accumulation of experiences. The aim of this study was to explore the role of organizational culture in creating a succession-planning system at the Ministry of Health and Medical Education in 2014. The present qualitative framework analysis held interviews with 23 director generals, administrative directors and deputies from the headquarters of the Iranian Ministry of Health and Medical Education in 2014 who were selected through snowball sampling. The data obtained were analyzed in MAXQDA-10. Codes were extracted using inductive techniques. The cultural factors affecting succession-planning at the Ministry of Health and Medical Education were identified and classified under three main areas, including the cultural factors related to the directors with four themes (Directors' job security, Constructive competition, Transparency and trust development, Creating opportunities), to the personnel with four themes (Organizational identity and loyalty, Trust in the organization, Talent and merit, Peer envy) and to the system with two themes (Values and beliefs, Politicization). Findings of the study show that establishment and institutionalization of the succession planning to the Ministry of Health and Medical Education is deeply affected by the components of organizational culture. Accordingly, unprofessional organization culture can deprive the organization of numerous advantages in multiple-succession planning.
Feeding goals sought by mothers of 3-5-year-old children.
Moore, Sue N; Tapper, Katy; Murphy, Simon
2010-02-01
One means through which children learn eating behaviours is the feeding strategies used by parents. Although research has studied the effects of parental feeding strategies on consumption, choice, and liking, little is known about the goals parents themselves seek. The study aimed to explore the feeding goals sought by parents of preschool children. An exploratory qualitative study using in-depth, semi-structured interviews was undertaken. Data were analysed using thematic and interpretative techniques. A snowballing sample of 12 mothers of children aged 3-5 years was used. Mothers were asked to recall and talk through their feeding experiences with this child. Probe questions were used to explore the reasoning behind the actions described. Data were transcribed and subjected to concurrent coding and interpretation. Mothers spontaneously classified their child as a 'good' or a 'bad' eater. Consumption emerged as the dominant feeding goal. For 'bad' eaters, a short-term goal of consuming any food, rather than no food, was adopted. For 'good' eaters, a long-term goal of consuming a varied, well-balanced diet was favoured. Liking as a feeding goal was not mentioned. Although the literature suggests that liking is the most appropriate feeding goal for the establishment of long-term healthy eating behaviours, parents do not knowingly, repeatedly and consistently target food likes as a direct outcome of their feeding strategies. Interventions that focus on 'how' parents feed their children, as well as 'what', are recommended.
Kamal, Susan; Holmberg, Christine; Russell, Jean; Bochenek, Tomasz; Tobiasz-Adamczyk, Beata; Fischer, Christiane; Tinnemann, Peter
2015-01-01
Background Pharmaceutical promotion activities in low and middle-income countries are often neither regulated nor monitored. While Egypt has the highest population and per capita use of medicines in the Arab world, we know very little about pharmaceutical companies promotional activities in the country. Aim To explore and analyze the perceptions of physicians towards promotional and marketing activities of pharmaceutical companies among physicians and pharmacists in Egypt. Methodology Perspectives of different healthcare system stakeholders were explored through semi-structured, in-depth interviews conducted in 2014 in Cairo, Egypt. Interviewees were chosen via purposive sampling and snowball technique. Each interview was recorded and transcribed. Then qualitative, thematic analysis was conducted with the help of NVIVO software. Findings The majority of physicians and pharmacists acknowledged exposure to pharmaceutical promotion. It was commonly believed that interaction with the pharmaceutical industry is necessary and both associated risks and benefits were acknowledged. The interviewed physicians considered themselves competent enough to minimize risks and maximize benefits to their prescribing habits. Views diverged on the extent and magnitude of the risks and benefits of pharmaceutical promotion, especially in regard to the influence on patients’ health. Conclusions Pharmaceutical promotion in Egypt is intensely directed at prescribers and dispensers. Physicians, pharmacists and policymakers expressed little skepticism to the influence of promotion towards their individual prescribing. Raising awareness of the pitfalls of pharmaceutical promotion is necessary, especially among the less experienced physicians. PMID:26473484
Facilitating factors and barriers to malaria research utilization for policy development in Malawi.
Mwendera, Chikondi A; de Jager, Christiaan; Longwe, Herbert; Phiri, Kamija; Hongoro, Charles; Mutero, Clifford M
2016-10-19
Research on various determinants of health is key in providing evidence for policy development, thereby leading to successful interventions. Utilization of research is an intricate process requiring an understanding of contextual factors. The study was conducted to assess enhancing factors and barriers of research utilization for malaria policy development in Malawi. Qualitative research approach was used through in-depth interviews with 39 key informants that included malaria researchers, policy makers, programme managers, and key stakeholders. Purposive sampling and snowballing techniques were used in identifying key informants. Interview transcripts were entered in QSR Nvivo 11 software for coding and analysis. Respondents identified global efforts as key in advancing knowledge translation, while local political will has been conducive for research utilization. Other factors were availability of research, availability of diverse local researchers and stakeholders supporting knowledge translation. While barriers included: lack of platforms for researcher-public engagement, politics, researchers' lack of communication skills, lack of research collaborations, funder driven research, unknown World Health Organization policy position, and the lack of a malaria research repository. Overall, the study identified facilitating factors to malaria research utilization for policy development in Malawi. These factors need to be systematically coordinated to address the identified barriers and improve on malaria research utilization in policy development. Malaria research can be key in the implementation of evidence-based interventions to reduce the malaria burden and assist in the paradigm shift from malaria control to elimination in Malawi.
Decision-making about prenatal genetic testing among pregnant Korean-American women.
Jun, Myunghee; Thongpriwan, Vipavee; Choi, Jeeyae; Sook Choi, Kyung; Anderson, Gwen
2018-01-01
to understand the prenatal genetic testing decision-making processes among pregnant Korean-American women. a qualitative, descriptive research design. referrals and snowball sampling techniques were used to recruit 10 Korean-American women who had been recommended for amniocentesis during pregnancy in the United States (U.S.). All participants were born in Korea and had immigrated to the U.S. The number of years living in the U.S. ranged from 4 to 11 (M=5.7). various regional areas of the U.S. the researchers conducted face-to-face or phone interviews using semi-structured interview guides. The interviews were conducted in the Korean language and lasted approximately 50-100minutes. The interview guides focused on the decision-making process and experiences with prenatal genetic testing, as well as reflections on the decisions. Four core themes emerged related to the participants' decision-making processes, according to their descriptions. These themes are (1) facing the challenges of decision-making, (2) seeking support, (3) determining one's preferred role in the decision-making process, and (4) feeling uncomfortable with the degree of patient autonomy in U.S. health care. researchers concluded that many distinctive factors influence the decision-making processes used by pregnant Korean-American women. The results have the potential to improve shared decision-making practices regarding prenatal genetic testing. clinicians need to understand the sociocultural underpinnings of pregnant Korean-American immigrants regarding prenatal genetic screening and testing as an initial step to engage these patients in shared decision-making. Published by Elsevier Ltd.
Social accountability and nursing education in South Africa
Armstrong, Susan J.; Rispel, Laetitia C.
2015-01-01
Background There is global emphasis on transforming health workforce education in support of universal health coverage. Objective This paper uses a social accountability framework, specifically the World Health Organization's six building blocks for transformative education, to explore key informants’ perspectives on nursing education in South Africa. Methods Using a snowballing sampling technique, 44 key informants were selected purposively on the basis of their expertise or knowledge of the research area. Semi-structured interviews were conducted with the key informants after informed consent had been obtained. The interviews were analysed using template analysis. Results South Africa has strategic plans on human resources for health and nursing education, training, and practice and has a well-established system of regulation and accreditation of nursing education through the South African Nursing Council (SANC). Key informants criticised the following: the lack of national staffing norms; sub-optimal governance by both the SANC and the Department of Health; outdated curricula that are unresponsive to population and health system needs; lack of preparedness of nurse educators; and the unsuitability of the majority of nursing students. These problems are exacerbated by a perceived lack of prioritisation of nursing, resource constraints in both the nursing education institutions and the health training facilities, and general implementation inertia. Conclusion Social accountability, which is an essential component of transformative education, necessitates that attention be paid to the issues of governance, responsive curricula, educator preparedness, and appropriate student recruitment and selection. PMID:25971402
NASA Astrophysics Data System (ADS)
Grant, G.; Cashman, K.; O'Connor, J.
2007-12-01
Interactions between hillslopes and channels can include a diverse range of geophysical processes, including debris flows, landslides, water floods, and volcanic flows. Each has its own characteristic time-energy trajectory. In some cases the energy of an event increases as it propagates through a landscape, primarily through the addition of mass and momentum; examples of these"rolling snowball" include the initiation and runout phases of volcanic lahars, avalanches, and debris flows. In other cases, loss of both mass and momentum from a moving body or fluid causes the energy of an event to dissipate with distance, similar to the unwinding of a rug; examples of these "magic carpets" include the depositional phases of lahars, pyroclastic flows, lava flows, and debris flows. Both snowballs and carpets leave distinctive imprints or tracks on the landscape that reflect the resultant mass flux from hill slope to channel. The efficiency of this mass transfer depends on the width and slope of the receiving channel and the rheological properties of the transported material. At one extreme, the channel easily accommodates mass flux from the slope, sometimes accompanied by fractionation into constituent phases. At the other extreme, mass from the hill slope can inundate and block the channel; these "sleeping dragons" modulate subsequent mass transfer down channel by changing the channel profile and bed properties. They also have the potential to "wake up" suddenly as mass failure and/or outbreak floods. Hazard prediction requires that the time-energy trajectory of each type of event be assessed; here we suggest some first order controls.
NASA Astrophysics Data System (ADS)
Harada, M.; Ozaki, K.; Tajika, E.; Sekine, Y.
2014-12-01
Rise of atmospheric oxygen in the Paleoproterozoic has been long recognized as a unidirectional, stepwise oxidation event. However, recent geochemical studies have reported the occurrences of deep-water oxygenation and sulfate accumulation in the Paleoproterozoic oceans [e.g., 1], suggesting that the oxidation was a dynamic transition associated with an overshoot of oxygen (so called, 'the Great Oxygen Transition' or GOT) [2]. During the GOT, the oxygen levels might have achieved 0.1-1 Present Atmospheric Level (PAL) over ~108 years [2]. Such an intense long-term oxygen overshoot appears to require some specific mechanism and strong oxidative forcing as a trigger. In this study, we provide the first numerical model that is capable of explaining the dynamics of the atmospheric oxygen during the GOT. We focus on a climate jump at the end of the Paleoproterozoic snowball glaciation as a trigger, and constrain the magnitude and duration of the snowball-induced oxygenation by using a biogeochemical cycle model. The results show that super greenhouse condition after the glaciation causes an increase in nutrient input from the continent to the oceans, which lead to a high rate of organic carbon burial in the oceans. This triggers a rapid jump in oxygen levels from low (<10-5 PAL) to high (~0.01 PAL) steady states within <104 years after deglaciation. The jump in oxygen levels is followed by the massive deposition of carbonate minerals, which corresponds to the "cap-carbonates". The elevated rate of organic carbon burial is prolonged over ~106 years, which results in an overshoot of atmospheric oxygen by up to ~0.1-1 PAL. The overshoot lasts for ~107-108 years because net consumption of oxygen accumulated in the atmosphere does not proceed efficiently. Such an extensive overshoot causes the oxygenation of the deep-water, and lead to the accumulation of sulfate ions by up to 1-10 mM and the deposition of sulfate minerals in the oceans. These results are in good agreement with the geological and geochemical data in the Paleoproterozoic [2, 3], implying that the Paleoproterozoic snowball glaciation would have been a sufficiently strong forcing to trigger the GOT. [1] Canfield et al. 2013, Pros. Natl. Acad. Sci. U.S.A., 110, 16736. [2] Lyons et al. 2014, Nature, 506, 307. [3] Schröder et al. 2008, Terra Nova, 20, 108.
Roth, A M; Rosenberger, J G; Reece, M; Van Der Pol, B
2013-04-01
Routine screening is a key component of sexually transmitted infection (STI) prevention and control; however, traditional programmes often fail to effectively reach men and women in hidden communities. To reduce prevalence, we must understand the programmatic features that would encourage utilization of services among asymptomatic individuals. Using incentivized snowball sampling, 44 women and men recently engaging in transactional sex were recruited (24 women, 20 men); median age 37 years. Respondents were offered the opportunity to collect genital, oropharyngeal and rectal samples for STI testing and completed a face-to-face interview about their experience with self-obtained sampling. Interviews were analysed using qualitative methods. Participants were unaware of potential risk for STI, but found self-sampling in non-clinical settings to be acceptable and preferable to clinic-based testing. All participants collected genital specimens; 96% and 4% collected oropharyngeal and rectal specimens, respectively. The burden of disease in this population was high: 38% tested positive for at least one STI. We detected multiple concomitant infections. Incorporating field collection of self-obtained samples into STI control programmes may increase utilization among high-risk populations unlikely to access clinic-based services. High infection rates indicate that individuals engaging in transactional sex would benefit from, and be responsive to, community-based self-sampling for STI screening.
The role of principal in optimizing school climate in primary schools
NASA Astrophysics Data System (ADS)
Murtedjo; Suharningsih
2018-01-01
This article was written based on the occurrence of elementary school changes that never counted because of the low quality, became the school of choice of the surrounding community with the many national achievements ever achieved. This article is based on research data conducted in primary schools. In this paper focused on the role of school principals in an effort to optimize school climate. To describe the principal’s role in optimizing school climate using a qualitative approach to the design of Multi-Site Study. The appointment of the informant was done by snowball technique. Data collection through in-depth interviews, participant observation, and documentation. Data credibility checking uses triangulation techniques, member checks, and peer discussions. Auditability is performed by the auditor. The collected data is analyzed by site analysis and cross-site analysis. The result of the research shows that the principal in optimizing the conducive school climate by creating the physical condition of the school and the socio-emotional condition is pleasant, so that the teachers in implementing the learning process become passionate, happy learners which ultimately improve their learning achievement and can improve the school quality.
Cortez, Fernanda C Prado; Boer, Douglas P; Baltieri, Danilo A
2011-09-01
This research compared street male sex workers in Santo André, Brazil, that reported consistent condom use with those that revealed inconsistent condom use with their clients, concerning personality aspects, impulsiveness, alcohol and drug consumption, depressive symptoms, sociodemographic data and criminal involvement. Eighty-six male sex workers were evaluated in face-to-face interviews at their place of work. A 'snowball' sampling procedure was used to access this hard-to-reach population. Male sex workers with inconsistent condom use showed greater involvement with criminal activities, higher reward dependence level and more frequent self-report of being HIV-positive. Conceptualisation of male sex workers' psychological characteristics may be required where HIV risk is not only attributed to sex work per se, but to other aspects such as personality-related factors and negative identity.
Brañas, Antía; Barrigón, María Luisa; Lahera, Guillermo; Canal-Rivero, Manuel; Ruiz-Veguilla, Miguel
2017-12-01
The Community Assessment of Psychic Experiences (CAPE) is an effective instrument for detection of the presence of psychotic symptoms and associated distress in the general population. However, little research has studied distress associated with positive psychotic-like experiences (PLEs). Our aim is to study PLE-related distress using the CAPE. In this study we analysed factors associated with differences in PLE-related distress in a sample of 200 non-clinical participants recruited by snowball sampling. Presence of PLEs and related psychological distress was measured using the CAPE questionnaire. The influence of age, gender, educational level and drug use was studied. In univariate analysis we found that gender and CAPE positive, depressive and negative scores, were associated with CAPE positive distress. Using multiple linear regression, we found that only the effect of gender, and the interaction between frequency of depression and gender, remained statistically significant. In our sample interaction between gender and depressive symptoms is a determining factor in distress associated with positive PLEs. The results of this study may be useful for the implementation of prevention programs. Copyright © 2017 Elsevier B.V. All rights reserved.
Demographic Predictors of Event-Level Associations between Alcohol Consumption and Sexual Behavior.
Wells, Brooke E; Rendina, H Jonathon; Kelly, Brian C; Golub, Sarit A; Parsons, Jeffrey T
2016-02-01
Alcohol consumption is associated with sexual behavior and outcomes, though research indicates a variety of moderating factors, including demographic characteristics. To better target interventions aimed at alcohol-related sexual risk behavior, our analyses simultaneously examine demographic predictors of both day- and event-level associations between alcohol consumption and sexual behavior in a sample of young adults (N = 301) who are sexually active and consume alcohol. Young adults (aged 18-29) recruited using time-space sampling and incentivized snowball sampling completed a survey and a timeline follow-back calendar reporting alcohol consumption and sexual behavior in the past 30 days. On a given day, a greater number of drinks consumed was associated with higher likelihood of sex occurring, particularly for women and single participants. During a given sexual event, number of drinks consumed was not associated with condom use, nor did any demographic predictors predict that association. Findings highlight associations between alcohol and sexual behavior, though not between alcohol and sexual risk behavior, highlighting the need for additional research exploring the complex role of alcohol in sexual risk behavior and the need to develop prevention efforts to minimize the role of alcohol in the initiation of sexual encounters.
NASA Astrophysics Data System (ADS)
Simpemba, Prospery C.
2015-08-01
Indigenous astronomy in the context of Zambia is the oral astronomy knowledge, culture and beliefs which relate to celestial bodies, astronomy events and related behaviour that are held by the elderly persons and passed on to younger generations. Much is not written down and with the passing away of the custodians, this knowledge is threatened to be extinct. A mini study of the astronomical beliefs and culture of the ancient Zambian community during the International Year of Astronomy (IYA) 2009 revealed that such knowledge existed. A comprehensive study assesses cultural and traditional knowledge on astronomy and to ascertain how much of this knowledge has been passed on to the younger generations. Open-ended interviews were conducted using questionnaires and focus group discussions. Respondents were identified by snowball sampling of the elderly people and random sampling of the middle aged and young. Nine randomly sampled districts of the Copperbelt Province were considered. The collected data has been analysed using MAXQDA software. Knowledge of traditional astronomy is high among the elderly people and declining with age hence the need for documenting and introducing it in the school curriculum and regular public discourse.
NASA Astrophysics Data System (ADS)
Light, Bonnie; Carns, Regina C.; Warren, Stephen G.
2016-07-01
The ice-albedo feedback mechanism likely contributed to global glaciation during the Snowball Earth events of the Neoproterozoic era (1 Ga to 544 Ma). This feedback results from the albedo contrast between sea ice and open ocean. Little is known about the optical properties of some of the possible surface types that may have been present, including sea ice that is both snow-free and cold enough for salts to precipitate within brine inclusions. A proxy surface for such ice was grown in a freezer laboratory using the single salt NaCl and kept below the eutectic temperature (-21.2°C) of the NaCl-H2O binary system. The resulting ice cover was composed of ice and precipitated hydrohalite crystals (NaCl · 2H2O). As the cold ice sublimated, a thin lag-deposit of salt formed on the surface. To hasten its growth in the laboratory, the deposit was augmented by addition of a salt-enriched surface crust. Measurements of the spectral albedo of this surface were carried out over 90 days as the hydrohalite crust thickened due to sublimation of ice, and subsequently over several hours as the crust warmed and dissolved, finally resulting in a surface with puddled liquid brine. The all-wave solar albedo of the subeutectic crust is 0.93 (in contrast to 0.83 for fresh snow and 0.67 for melting bare sea ice). Incorporation of these processes into a climate model of Snowball Earth will result in a positive salt-albedo feedback operating between -21°C and -36°C.
Characterizing Marine Habitat Space on a Snowball Earth with a 3D Global Climate Model
NASA Astrophysics Data System (ADS)
Sohl, L. E.; Chandler, M. A.; Lingo, F.
2016-12-01
The impact of long-term, severe cold conditions during the Neoproterozoic glacial events ( 715-635 Ma) on the origins and evolution of metazoans remains unclear, even as recent paleobiological analyses lend support to the notion that metazoans appeared and diversified long before their first definitive appearance in the Ediacaran fossil record (Cohen and MacDonald, Paleobiology 41:610, 2015; Spence et al., Sedimentology 63:253, 2016). Cumulative geologic evidence for active hydrologic cycling and the presence of open waters in near-shore environments suggests that a fully ice-covered ocean (a "hard" Snowball) at this time in Earth history is unlikely, opening up the possibility that life did more than just survive in a few localized refugia. Here we present results from 3D climate simulations of a Neoproterozoic Snowball Earth, using the NASA/GISS global climate model (GCM) ModelE2 to explore oceanographic conditions during the Sturtian glacial interval. The GCM was allowed to run to an equilibrium state, with forcings (reduced solar luminosity, CO2) that yielded a stable sea ice front at approximately 30 degrees latitude. Among the prognostic variables available for analysis are ocean temperature and salinity gradients in three dimensions, and rates and regions of vertical mixing that enhance the distribution of heat and nutrients in the oceans. Using information derived from physical limitations of certain modern organisms likely related to early complex life (e.g., demosponges) we review the geographic distribution of potential habitat space. Our preliminary analysis suggests that salinity rather than temperature could be a key constraint on the distribution of complex life, a contrast to the expectation of temperature as a key limiting factor.
Continental flood basalt weathering as a trigger for Neoproterozoic Snowball Earth
NASA Astrophysics Data System (ADS)
Cox, Grant M.; Halverson, Galen P.; Stevenson, Ross K.; Vokaty, Michelle; Poirier, André; Kunzmann, Marcus; Li, Zheng-Xiang; Denyszyn, Steven W.; Strauss, Justin V.; Macdonald, Francis A.
2016-07-01
Atmospheric CO2 levels and global climate are regulated on geological timescales by the silicate weathering feedback. However, this thermostat has failed multiple times in Earth's history, most spectacularly during the Cryogenian (c. 720-635 Ma) Snowball Earth episodes. The unique middle Neoproterozoic paleogeography of a rifting, low-latitude, supercontinent likely favored a globally cool climate due to the influence of the silicate weathering feedback and planetary albedo. Under these primed conditions, the emplacement and weathering of extensive continental flood basalt provinces may have provided the final trigger for runaway global glaciation. Weathering of continental flood basalts may have also contributed to the characteristically high carbon isotope ratios (δ13 C) of Neoproterozoic seawater due to their elevated P contents. In order to test these hypotheses, we have compiled new and previously published Neoproterozoic Nd isotope data from mudstones in northern Rodinia (North America, Australia, Svalbard, and South China) and Sr isotope data from carbonate rocks. The Nd isotope data are used to model the mafic detrital input into sedimentary basins in northern Rodinia. The results reveal a dominant contribution from continental flood basalt weathering during the ca. 130 m.y. preceding the onset of Cryogenian glaciation, followed by a precipitous decline afterwards. These data are mirrored by the Sr isotope record, which reflects the importance of chemical weathering of continental flood basalts on solute fluxes to the early-middle Neoproterozoic ocean, including a pulse of unradiogenic Sr input into the oceans just prior to the onset of Cyrogenian glaciation. Hence, our new data support the hypotheses that elevated rates of flood basalt weathering contributed to both the high average δ13 C of seawater in the Neoproterozoic and to the initiation of the first (Sturtian) Snowball Earth.
NASA Astrophysics Data System (ADS)
Kendall, Brian S.; Creaser, Robert A.; Ross, Gerald M.; Selby, David
2004-06-01
New Re-Os isotopic data were obtained from chlorite-grade black shales from the upper Old Fort Point Formation (Windermere Supergroup), a post-glacial Neoproterozoic marker horizon in western Canada. A Re-Os isochron date of 634±57 Ma (MSWD=65, n=5) was determined using the conventional inverse aqua regia digestion medium. However, dissolution of the same samples with a new CrO 3-H 2SO 4 dissolution technique [Chem. Geol. 200 (2003) 225] yielded a much more precise date of 607.8±4.7 Ma (MSWD=1.2). Both dates are in agreement with existing U-Pb age constraints that bracket the Old Fort Point Formation between ˜685 and ˜570 Ma. The distinctive Re-Os systematics recorded by the two analytical protocols is explained by dissolution of a variably radiogenic, detrital Os component by the aqua regia method. In contrast, the CrO 3-H 2SO 4 technique minimizes this detrital component by selectively dissolving organic matter that is dominated by hydrogenous (seawater) Re and Os. The date of 607.8±4.7 Ma is thus interpreted as the depositional age for the upper Old Fort Point Formation providing a minimum age constraint for the timing of the second Windermere glaciation in western Canada. This ice age is correlative with the Marinoan (˜620-600 Ma) ice age and older than the ˜580-Ma Gaskiers glaciation of northeastern North America. The new Re-Os age determined from the CrO 3-H 2SO 4 digestion technique thus provides further support to a growing body of evidence for a global Marinoan glacial episode. Such an interpretation would not be discernable from the imprecise Re-Os date obtained with the aqua regia protocol. These results also indicate the potential for Re-Os radiometric dating of black shales that was not previously recognized. Importantly, neither chlorite-grade metamorphism nor the low organic content (TOC <1%) of the Old Fort Point Formation precluded the determination of a precise Re-Os depositional age using the CrO 3-H 2SO 4 analytical protocol.
Firmo, Angélica M S; Tognella, Mônica M P; Silva, Saulo R; Barboza, Raynner R R D; Alves, Rômulo R N
2012-03-19
Blue Land Crab (Cardisoma guanhumi) is one of the most important crustacean species captured and commercialized in Brazil. Although this species is not considered to be threatened with extinction, populations of C. guanhumi are known to be rapidly diminishing due to heavy harvesting pressures and degradation of their natural habitats, highlighting the necessity of developing and implanting management and protection strategies for their populations. There have been no ethnozoological publications that have focused specifically on C. guanhumi, in spite of importance of this type of information for developing efficient management plans of resource utilization. So, the present work describes the ethnoecological aspects of the capture and commercialization of C. guanhumi by a fishing community in northeastern Brazil. Field work was carried out in the municipality of Mucuri, Bahia in Brazil, between the months of January and March/2011 through the use of open semi-structured interviews with all of the crustacean harvesters in city who acknowledged their work in capturing this species, totaling 12 interviewees. The informants were identified through the use of the "snowball" sampling technique. In addition to the interviews themselves, the "guided tour" technique and direct observations was employed. According all the interviewees, the C. guanhumi is popularly called "guaiamum" and is collected in "apicum" zones. They recognize sexual dimorphism in the species based on three morphological characteristics and the harvesters also pointed two stages in the reproductive cycle during the year and another phase mentioned by the interviewees was ecdysis. All of the interviewed affirmed that the size and the quantities C. guanhumi stocks in Mucuri have been diminishing. All of the interviewees agreed that the species and other mangrove resources constituted their principal source of income. The harvesters dedicated three to five days a week to collect Blue Land Crabs and the principal technique utilized for capturing is a trap called a "ratoeira" (rat-trap). The results of the present work demonstrated that the community retains a vast and important volume of knowledge about C. guanhumi that could subsidize both scientific studies and the elaboration of viable management and conservation strategies for this species.
Not a Snowball's Chance in Hell.
ERIC Educational Resources Information Center
Koontz, Jonathan W.
1980-01-01
Describes the involvement of administrators, faculty, and students in a successful publicity campaign designed to gain public backing for a referendum in support of Palm Beach Junior College, Florida. Examines various publicity tactics utilized, including newspaper advertisements and editorials, slideshows and lectures, and the distribution of…
NASA Technical Reports Server (NTRS)
Roddy, D. J.
1977-01-01
A tabular outline of comparative data is presented for 340 basic dimensional, morphological, and structural parameters and related aspects for three craters of the flat-floored, central uplift type, two of which are natural terrestrial impact craters and one is a large-scale experimental explosion crater. The three craters are part of a general class, in terms of their morphology and structural deformation that is represented on each of the terrestrial planets including the moon. One of the considered craters, the Flynn Creek Crater, was formed by a hypervelocity impact event approximately 360 m.y. ago in what is now north central Tennessee. The impacting body appears to have been a carbonaceous chondrite or a cometary mass. The second crater, the Steinheim Crater, was formed by an impact event approximately 14.7 m.y. ago in what is now southwestern Germany. The Snowball Crater was formed by the detonation of a 500-ton TNT hemisphere on flat-lying, unconsolidated alluvium in Alberta, Canada.
2013-12-23
Saturn's moon Enceladus, covered in snow and ice, resembles a perfectly packed snowball in this image from NASA's Cassini mission. Cassini has imaged Enceladus many times throughout its mission, discovering a fractured surface and the now-famous geysers that erupt icy particles and water vapor from fractures crossing the moons' 200-mile-wide (300-kilometer-wide) south polar terrain. The mountain ridge seen in the south in this image is part of the undulating mountain belt that circumscribes this region. This view looks toward the leading side of Enceladus (313 miles, 504 kilometers across). North on Enceladus is up and rotated 6 degrees to the left. The image was taken with the Cassini spacecraft narrow-angle camera on March 10, 2012, using filters sensitive to ultraviolet, visible and infrared light (spanning wavelengths from 338 to 750 nanometers). The view was acquired at a distance of approximately 106,000 miles (170,000 kilometers) from Enceladus. Image scale is 3,336 feet (1 kilometer) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA17182
Smoking relapse situations among a community-recruited sample of Spanish daily smokers.
Piñeiro, Bárbara; López-Durán, Ana; Martínez-Vispo, Carmela; Fernández Del Río, Elena; Martínez, Úrsula; Rodríguez-Cano, Rubén; Míguez, M Carmen; Becoña, Elisardo
2017-12-01
Relapse is a common factor within the behavior change process. However, there is scarce and limited knowledge of smoking relapse situations in population-based samples. The aim of this study was to identify smoking relapse situations among a sample of Spanish relapsers from the general population. A sample of 775 relapsers was recruited among the general population using a snowball method. Participants completed a survey including sociodemographic, smoking-related and psychopathology variables. Smoking relapse situations were identified through specific questions assessing different aspects related to the last relapse episode. The majority of smoking relapse situations were attributed to positive affect (36.6%) and negative affect (34.3%), followed by lack of control (10.1%), smoking habit (6.7%), craving or nicotine withdrawal (6.3%), and social pressure (5.9%). Being unemployed and having a mental disorder in the past increased the likelihood of relapse in situations of negative affect. Being single and having quit smoking to save money were associated with an increased likelihood of relapse in situations of positive affect. Affect plays a significant role in smoking relapse among a community sample of unassisted Spanish smokers. Relapse may be much more of an affective and situational process than a habit, physiological or social pressure. Findings from this study may help develop tailored community smoking relapse prevention strategies or programs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Mehrtak, Mohamad; Vatankhah, Soodabeh; Delgoshaei, Bahram; Gholipour, Arian
2014-01-01
Background: Succession planning promotes the culture of private ownership, staff loyalty to the organization and develops organizational commitment, and increases organizational stability. The study was conducted to examine the status of succession planning in the Iranian health system in order to highlight the key concepts, provide new insight, and attract the attention of senior managers of the Ministry of Health and Medical Education to the importance of succession planning in achieving organizational goals. Methods: In a qualitative study with a framework analysis approach, semi-structured interviews were conducted with a sample selected using purposive and snowball sampling procedure. The MAXQDA-10 was used to apply the codes and manage the data. The codes were extracted using inductive and deductive methods. Results: Fourteen themes and six main subthemes were identified, including planning, organizational culture, system approach, competency model, career path, and senior managers. Our findings indicate a lack of succession planning in the Iranian health system. Conclusion: lack of succession planning could lead to inefficiency and ineffectiveness in health services provision. Implementation of succession planning could maximize human resources utilization. PMID:25168998
Associations between childhood maltreatment and sex work in a cohort of drug-using youth.
Stoltz, Jo-Anne Madeleine; Shannon, Kate; Kerr, Thomas; Zhang, Ruth; Montaner, Julio S; Wood, Evan
2007-09-01
Although research has examined the impacts of childhood maltreatment among various marginalized populations, few studies have explored the relationship between child abuse and subsequent involvement in sex work among drug-using street-involved youth. In the present study, the relationships between the level of childhood maltreatment and involvement in sex work were examined using the Childhood Trauma Questionnaire (CTQ) as part of an extensive interview protocol in an ongoing prospective cohort study of street-involved youth in Vancouver, Canada. Between September 2005 and June 2006, 361 youth were recruited using extensive outreach methods and snowball sampling. The prevalence rates for abuse in the sample were 73% for physical abuse; 32.4% for sexual abuse; 86.8% for emotional abuse; 84.5% for physical neglect; and 93% for emotional neglect. Univariate and logistic regression analyses demonstrated that not only was sexual abuse independently associated with sex work, but emotional abuse was as well. These findings have implications for early intervention efforts aimed at vulnerable, high-risk youth populations as well as intervention strategies for active sex trade workers.
Mehrtak, Mohamad; Vatankhah, Soodabeh; Delgoshaei, Bahram; Gholipour, Arian
2014-05-30
Succession planning promotes the culture of private ownership, staff loyalty to the organization and develops organizational commitment, and increases organizational stability. The study was conducted to examine the status of succession planning in the Iranian health system in order to highlight the key concepts, provide new insight, and attract the attention of senior managers of the Ministry of Health and Medical Education to the importance of succession planning in achieving organizational goals. In a qualitative study with a framework analysis approach, semi-structured interviews were conducted with a sample selected using purposive and snowball sampling procedure. The MAXQDA-10 was used to apply the codes and manage the data. The codes were extracted using inductive and deductive methods. Fourteen themes and six main subthemes were identified, including planning, organizational culture, system approach, competency model, career path, and senior managers. Our findings indicate a lack of succession planning in the Iranian health system. lack of succession planning could lead to inefficiency and ineffectiveness in health services provision. Implementation of succession planning could maximize human resources utilization.
NASA Astrophysics Data System (ADS)
Banh, My-Le
The purpose of this qualitative exploratory case study was to explore the lack of motivation of engineers with more than 15 years of experience working in aerospace companies in southern California. The sample size for this study consisted of 18 senior engineers. These participants held either a bachelor's or master's degree in engineering fields. Participants were recruited through networking with colleagues and snowball sampling. The data was collected through face-to-face and phone interviews. Participants also had the opportunity to review their responses after the interview. The data analysis resulted in 12 themes regarding the participants' perception of motivation. The top six predominant themes were (1) challenging and new assignments, (2) commitment, (3) opportunity, (4) supporting from managers, (5) team spirit, and (6) open communication. The study resulted in an in-depth understanding of how important motivation is to senior engineers. Based on the findings, leaders should create opportunities for senior employees to work on challenging assignments, acquire autonomy, and obtain more responsibilities. Providing such opportunities may motivate employees to perform well and committee with the organizations.
Investigation of the reasons for not using helmet among motorcyclists in Kerman, Iran.
Maghsoudi, Aliasghar; Boostani, Dariush; Rafeiee, Manoochehr
2018-03-01
This study was carried out to investigate reasoning and interpretation of motorcyclists for not using helmet utilizing qualitative methodology of 'grounded theory'. The field of the study was Kerman, a cultural-historical city at the south-east of Iran. Participants were 21 young male motorcyclists. Two sampling strategies were used: maximum variation and snowball sampling. To collect data, in-depth, open-ended interviews were conducted. Data analysis yielded seven categories: fatalism; a barrier to social relationships; peer group pressure and negative labelling; messing up the appearance; disturbance in hearing and vision; barrier to normal breathing; and heaviness and superfluity of helmet. Based on the findings of the current study, it could be concluded that socio-cultural contexts, motorcyclists' worldview and partly helmet-related problems are of the main factors which affect motorcycling. Therefore, the studies, policy-makings, and intervening programmes to control injury and to promote safety among motorcyclists should be focused on socio-cultural barriers to helmet use in general and changing the motorcyclists' standpoints toward fatalism in particular. Helmet-related problems should be considered, too.
NASA Astrophysics Data System (ADS)
Fiorella, R.; Poulsen, C. J.
2013-12-01
The enigmatic Neoproterozoic geological record suggests the potential for a fully glaciated 'Snowball Earth.' Low-latitude continental position has been invoked as a potential Snowball Earth trigger by increasing surface albedo and decreasing atmospheric CO2 concentrations through increased silicate weathering. Herein, climate response to reduction of total solar irradiance (TSI) and CO2 concentration is tested using four different land configurations (aquaplanet, modern, Neoproterozoic, and low-latitude supercontinent) with uniform topography in the NCAR Community Atmosphere Model (CAM, version 3.1) GCM with a mixed-layer ocean. Despite a lower global mean surface albedo at 100% TSI for the aquaplanet scenario, the threshold for global glaciation decreases from 92% TSI in the aquaplanet configuration to 85% TSI with a low-latitude supercontinent. Climate sensitivity, as measured by the equilibrium temperature response to TSI and CO2 changes, varied across all four geographies at each forcing pair. The range of sensitivities observed suggests that climate feedback strengths are strongly dependent on both paleogeography and forcing. To identify the mechanisms responsible for the observed breadth in climate sensitivities, we calculate radiative kernels for four different TSI and CO2 forcing pairs in order to assess the strengths of the water vapor, albedo, lapse rate, Planck, and cloud feedbacks and how they vary with both forcing and paleogeography. Radiative kernels are calculated using an uncoupled version of the CAM3.1 radiation code and then perturbing climate fields of interest (surface albedo, specific humidity, and temperature) by a standard amount. No cloud kernels are calculated; instead, the cloud feedback is calculated by correcting the change in cloud radiative forcing to account for cloud masking. We find that paleogeography strongly controls how the water vapor and lapse rate feedbacks respond to different forcings. In particular, low latitude continents diminish the change in water vapor feedback strengths resulting from changes in forcing. Continental heating intensifies the Walker circulation, enhancing surface evaporation and moistening the marine troposphere. Additionally, dehumidification of the troposphere over large tropical continents in CAM3.1 increases direct heating by decreasing cloud cover. As a result, in the absence of potential silicate weathering feedbacks, large tropical landmasses raise the barrier to initiation of Snowball events. More generally, these simulations demonstrate the substantial influence of geography on climate sensitivity and climate feedback mechanisms, and challenge the notion that reduced continental area early in Earth history might provide a solution to the Faint Young Sun Paradox.
Relationship between the Neoproterozoic snowball Earth and Cambrian explosion
NASA Astrophysics Data System (ADS)
Maruyama, S.; Yoshihara, A.; Isozaki, Y.
2007-12-01
Origin of snowball Earth has been debated in terms of greenhouse gas (e.g., Hoffman and Schrag), obliqueness of Earth's rotation axis (Williams, 1975), true polar wander (Evans, 2003), Galactic cosmic ray radiation (Shaviv and Veizer, 2003; Svensmark, 2006), or weakened geomagnetism (Maruyama and Yoshihara, 2003). A major difficulty for the greenhouse gas hypothesis is the on-off switch causing decrease and increase of appropriate amounts of CO2 by plume- and plate tectonics, and also in available amount of CO2 in atmosphere to be consistent with the observations. In contrast, the cosmic ray radiation models due to the star burst peaked at 2.5- 2.1 Ga and 1.4-0.8 Ga can explain on-off switch more easily than the greenhouse gas model. Cosmic ray radiations, however, must be modified by the geomagnetic intensity, fluctuating 150"% to < 10"% of the present-day level through geologic time. Our compilation suggests the idea of extensive glaciation appeared when the intensity decreased below 50% of the present-day value, as typically seen in the Neoproterozoic time. This proposes the idea of extensive cloudiness by increased cosmic rays in the Neoproterozoic to cause the snowball Earth. Time difference between the Neoproterozoic snowball Earth and Cambrian explosion is as large as 250 millions years, and this refuses their direct close-relationship. Role of frequent mass extinctions, i.e., 8 times during 100 m.y. from 585 Ma to 488 Ma, during the Ediacaran and Cambrian, has been proposed (Zhu et al., 2007). This frequency is one order of magnitude higher compared to that in the post-Ordovician time. Yet, the Cambrian explosion cannot be explained by mass extinction which replaced the vacant niches shortly after the mass extinction and never created a new animal with a new body plan. A new model proposed herein is derived from weakened geomagnetism and resultant extensive cosmic radiation to alter gene and genome for a long period over advancement of low magnetic intensity and cosmic radiations (Svensmark, 2006) from 1.2-0.8Ga. As to the new body plans of animals, it took an appreciably long time to prepare all 34 genometypes before the apparent Cambrian explosion. Geochemically extreme conditions and widened shallow marine environment on continental shelf by the return-flow of sweater into mantle in the Late Neoptroterozoic were the associated critical conditions to alter genomes during 1.2-0.52 Ga appreciably before the final consequence called the Cambrian explosion.
NASA Astrophysics Data System (ADS)
Tang, T.; Raub, T. D.; Wang, Z.
2013-12-01
Strontium isotope chemostratigraphy in limestones appear to track a near monotonic rising trend from the tail of the breakup of the supercontinent Rodinia at ~750 Ma into the latest Ediacaran Period at ~ 550 Ma (Halverson et al., 2007). This offers a potentially powerful tool to date carbonates occurring within this time period of stepwise environmental oxidation. Furthermore, aspects of the Snowball Earth hypothesis predict that some magnitude of 87Sr/86Sr excursions of seawater is expected at multiple intervals during this time, because balancing influences from prolonged synglacial hydrothermal input in entombed oceans, deglacial freshwater plumes of varying temperature and salinity, and enhanced postglacial silicate weathering from the continents can leave multiple isotopic trends plausible during these critical intervals. The positions of these deglaciations appear to correlate specifically to marine oxidation events, with cause/effect relations still under investigation. To capitalize on all of these interpretive possibilities, it is crucial to establish a high-precision and high-resolution strontium chemostratigraphic record over both short and long timescales. However, difficulties in establishing such a record based on carbonates are associated with 1) diagenetic influence over extensive geological time; and 2) petrologic complexities of the studied samples. Using a sequential digestion technique, Liu et al. (2013) demonstrated that these hurdles can be overcome, and that primary 87Sr/86Sr ratios of contemporaneous seawater can be obtained from Marinoan cap dolostones (~635 Ma), which have considerably less Sr than limestones, and whose Sr isotope compositions are commonly ignored in the strontium chemostratigraphic record. This leads to several viable, specific interpretations about the origin of Marinoan cap carbonate: either 1) very fast deposition; 2) slow deposition in a long-Sr-residence-time ocean; 3) mid-cap deposition in a freshwater "Glacial Lake Harland" of high-Ca, Sr composition; or 4) brine-influenced diagenesis exploiting specific horizons in the cap. As a broader implication, many extant Sr-isotope chemostratigraphies of Marinoan cap carbonate may be inaccurate, and in general, recrystallized impure (and low-Sr) carbonates, and dolomites in particular, are probably best studied with the serial digestion technique. We apply this sequential digestion technique to another Ediacaran cap carbonate with significant siliciclastic content, the anomalous cap limestone synchronous with deglaciation of ~581 Ma Gaskiers ice age in Newfoundland's Avalon zone. Although some textural and compositional differences exist between ~635 Ma Nuccaleena and ~581 Ma Gaskiers cap, the sequential digestion technique again appears to provide clarity by suggesting less-altered and more-altered fractions from various sample levels. We will discuss implications for the nature of Gaskiers glaciation and accompanying environmental oxidation, its global correlations, and the utility of the existing Ediacaran Sr-chemostratigraphic reference curve.
Hongal, S; Torwane, Na; Chandrashekhar, Br; Saxena, V; Chavan, Kr
2014-11-01
Eunuchs are considered as the most vulnerable, frustrated, and insecure community. The accessibility to medical and dental facilities for the eunuchs is nearly nonexistent. Due to these reasons, they might be at a high risk of developing severe dental problems like tooth loss. The present cross-sectional study aimed to evaluate the dental prosthetic status and prosthetic needs among eunuchs residing in Bhopal city, Madhya Pradesh, India. On the basis of convenient nonprobability snowball sampling technique, all the self-identified eunuchs residing in the city of Bhopal along with a matched control consisting of cross section of the general population residing in the same locality was examined to evaluate the prosthetic status and prosthetic needs of the population. All the obtained data were entered into a personal computer on Microsoft excel sheet and analyzed using the software; Statistical Package for Social Science version 20. Data comparison was done by applying Chi-square test. A total of 639 subjects comprised of 207 eunuchs, 218 males and 214 females. Among all participants, 2.8% (18/639) were having prosthesis. The overall prosthetic status among males was 3.2% (7/218) followed by 2.9% (6/207) eunuchs and 2.3% (5/214) females. However, need for multi-unit and combination of one and more unit prosthesis for upper and lower jaws was higher in males compared to females and eunuchs, but the difference was not statistically significant. The findings of this study clearly demonstrate a high unmet need for prosthetic care among the population surveyed.
Sukkarieh-Haraty, Ola; Egede, Leonard E; Abi Kharma, Joelle; Bassil, Maya
2018-06-01
Fatalism is a grounded cultural belief that is common among Arabs and is known to hinder self-care in chronic diseases including diabetes (Nabolsi and Carson in Scand J Caring Sci 25(4):716-724, 2011). The purpose of this study is to identify predictors of diabetes fatalism in this population. Data on 280 Lebanese patients with type 2 diabetes (mean age 58.24 ± 13.48 years; mean HbA1c 7.90 ± 1.90%; 53.76% females) recruited from one hospital in greater Beirut, Lebanon, and from the community using snowballing technique were examined. Multiple linear regression was used to assess the independent association between diabetes fatalism and demographic and patient characteristics. Age (β = -.14, 95% CI -.27, -.002), BMI (β = .35, 95% CI .15; .54), level of education (β = -3.98, 95% CI -7.64; -.32) and number of diabetes problems (β = -5.03, 95% CI -9.89; -.18) were significantly associated with diabetes fatalism in the regression model. The combination of demographic and patient characteristics accounted for 14.5% of the variance in diabetes fatalism scores' change. Patients with type 2 diabetes who exhibited more fatalistic attitudes were younger, of lower education levels, had higher BMI and had fewer diabetes comorbidities. Such findings are crucial for healthcare practitioners to identify fatalistic patients and to tailor culturally appropriate strategies in diabetes management. Further studies are warranted to explore other potential determinants of diabetes fatalism with larger sample and non-Lebanese Arabic population.
Mitra, Monika; Smith, Lauren D; Smeltzer, Suzanne C; Long-Bellil, Linda M; Sammet Moring, Nechama; Iezzoni, Lisa I
2017-07-01
Women with physical disabilities are known to experience disparities in maternity care access and quality, and communication gaps with maternity care providers, however there is little research exploring the maternity care experiences of women with physical disabilities from the perspective of their health care practitioners. This study explored health care practitioners' experiences and needs around providing perinatal care to women with physical disabilities in order to identify potential drivers of these disparities. We conducted semi-structured telephone interviews with 14 health care practitioners in the United States who provide maternity care to women with physical disabilities, as identified by affiliation with disability-related organizations, publications and snowball sampling. Descriptive coding and content analysis techniques were used to develop an iterative code book related to barriers to caring for this population. Public health theory regarding levels of barriers was applied to generate broad barrier categories, which were then analyzed using content analysis. Participant-reported barriers to providing optimal maternity care to women with physical disabilities were grouped into four levels: practitioner level (e.g., unwillingness to provide care), clinical practice level (e.g., accessible office equipment like adjustable exam tables), system level (e.g., time limits, reimbursement policies), and barriers relating to lack of scientific evidence (e.g., lack of disability-specific clinical data). Participants endorsed barriers to providing optimal maternity care to women with physical disabilities. Our findings highlight the needs for maternity care practice guidelines for women with physical disabilities, and for training and education regarding the maternity care needs of this population. Copyright © 2016 Elsevier Inc. All rights reserved.
Bain, Mathew Gabriel; Lian, Cheah Whye; Thon, Chang Ching
2014-04-01
Breaking of bad news is an important component in the management of cancer patients. This study aimed to assess the perceptions of breaking bad news of cancer diagnosis. It was a cross-sectional study using Breaking Bad News Assessment Schedule (BAS) questionnaire on cancer patients in Serian district. Using snowballing sampling method, a total of 134 patients were interviewed face-to-face after the consent was obtained from each of the respondents. Data was entered and analyzed using SPSS version 19.0. Majority were comfortable with the current method of breaking bad news. The main aspects found to be the areas of concern were the importance of the usage of body language, management of time and identifying patients' key area of concerns. There were significant difference between sex and "information giving" (P = 0.028) and "general consideration" (P = 0.016) and also between "the age and setting the scene" (P = 0.042). Significant difference was also found between the types of cancer and "the setting of scene" (P = 0.018), "breaking bad news technique" (P = 0.010), "eliciting concerns" (P = 0.003) and "information giving" (P = 0.004). Good and effective communication skill of breaking bad news is vital in the management of cancer patients. As the incidence of new cases of cancer increase every year, breaking of bad news has become a pertinent to the medical professionals' role. Specific aspects of communication skills based on local characteristics should be more emphasized in the formulation of training for doctors.
HIV susceptibility among clients of female sex workers in Indonesia: a qualitative inquiry.
Mwanri, Lillian; Fauk, Nelsensius Klau; Kustanti, Christina Yeni; Ambarwati, Atik; Merry, Maria Silvia
2018-02-15
Background: The spread of HIV infection among men in Indonesia continues to increase every year. Clients of female sex workers (FSWs) are a group at higher risk of acquiring HIV infection due to their frequent engagement in sexual acts with sex workers. This study aimed to identify factors of susceptibility to HIV infection among clients of FSWs. Methods: A qualitative inquiry using one-on-one in-depth interviews was conducted in the Belu and Malaka districts of Indonesia from January to April 2017. The study participants (n =42) were the clients of FSWs recruited using the snowball sampling technique. The inclusion criteria were: being a client of FSWs and being aged 18 years or more. Data were analysed using a framework analysis. Results: Findings were grouped into two main emerging themes that included behavioural and socioeconomic factors. Behavioural factors that mediated HIV susceptibility among clients of FSWs were: frequent engagement in unsafe sex with multiple sex workers; low perceptions of the relevance of available HIV and AIDS services and limited access to these services; and HIV stigma or fear of being labelled as HIV positive. Socioeconomic factors included: participants' economic situation; and individuals' household responsibility and ability to afford FSWs services. Conclusions: The study results indicate the need to reformulate and improve HIV and AIDS-related services, including increasing the level of availability of HIV service points and the dissemination of knowledge and information about HIV and AIDS and condom use and making them accessible to both FSWs and their clients in Belu and Malaka districts.
Varela, Andrea Ramirez; Pratt, Michael; Harris, Jenine; Lecy, Jesse; Salvo, Deborah; Brownson, Ross C; Hallal, Pedro C
2018-06-01
Little has been published about the historical development of scientific evidence in the physical activity (PA) and public health research field. The study aimed to examine the evolution of knowledge in this field. A structured literature review using formal citation network analysis methods was conducted in June-2016. Using a list of influential PA publications identified by domain experts, a snowball sampling technique was used to build a compact citation network of 141 publications that represents the backbone of the field. Articles were coded by study type and research team characteristics, then analyzed by visualizing the citation network and identifying research clusters to trace the evolution of the field. The field started in the 1950s, with a health sciences focus and strong North American and European leadership. Health outcome studies appeared most frequently in the network and policy and interventions least. Critical articles on objective measurement and public policy have influenced the progress from an emphasis on health outcomes research at early stages in the field to the more recent emerging built environment and global monitoring foci. There is only modest cross-citation across types of study. To our knowledge, this paper is the first to systematically describe the development of research on PA and public health. The key publications include fundamental ideas that remain citable over time, but notable research and dissemination gaps exist and should be addressed. Increasing collaboration and communication between study areas, encouraging female researchers, and increasing studies on interventions, evaluation of interventions and policy are recommended. Copyright © 2017 Elsevier Inc. All rights reserved.
Redondo Martín, S; Bolaños Gallardo, E; Almaraz Gómez, A; Maderuelo Fernández, J A
2005-10-31
To analyse the opinions of the users of primary care on the care that they receive and to identify the principal areas of satisfaction. Qualitative study using discussion groups and open interviews during the period January-May 2003. Health areas of Valladolid, Spain. The inclusion criteria were: to have attended a primary care clinic at sometime and to be between 35 and 80 years old. Recruitment was carried out through key informants, using the snowball technique. 6 discussion groups and interviews with representatives of 3 nursing and 1 residents association were carried out. Structural sampling was carried out as regards the variables that influenced satisfaction. The conversations were recorded using tape recorders and literally transcribed on paper. The analysis of the texts was carried out by 2 investigators and concordance was sought between them. The principal areas related to satisfaction were: the treatment received from the professionals, which is considered a fundamental part of care, combined with the technical quality, continuity of the care, the admission services, the bureaucratic procedures, the barriers for accessing specialised services, and waiting lists. Personalized care, the time dedicated by the professional, the continuity of care, and waiting lists are the principal areas related to the perceived satisfaction of the patients. The possible responses to improve this situation are: the implementation of changes in the care management and organisation which would simplify the procedures, investment of resources (human and economic), changes in the model of the professional-patient relationship, and improvements in undergraduate and postgraduate training.
A prospective health impact assessment of the international astronomy and space exploration centre
Winters, L
2001-01-01
STUDY OBJECTIVES—Assess the potential health impacts of the proposed International Astronomy and Space Exploration Centre on the population of New Wallasey. Contribute to the piloting of health impact assessment methods. DESIGN—Prospective health impact assessment involving brainstorming sessions and individual interviews with key informants and a literature review. SETTING—New Wallasey Single Regeneration Budget 4 area. PARTICIPANTS—Key stakeholders including local residents' groups selected through purposeful snowball sampling. MAIN RESULTS—Recommendations are made that cover issues around: transport and traffic; civic design; security; public safety, employment and training. CONCLUSIONS—Health impact assessment is a useful pragmatic tool for facilitating wide consultation. In particular engaging the local population in the early planning stages of a proposed development, and assisting in highlighting changes to maximise the positive health influences on affected communities. Keywords: health impact assessment; health determinants PMID:11351002
Ali, Aishah; Howden-Chapman, Philippa
2007-01-01
This study was undertaken to explore the roles played by bidan kampungs and understand their contribution to rural Malay women during pregnancy and childbirth hundred sixteen pregnant women, 13 Western midwives, and 12 bidan kampungs were recruited using convenience and snowball sampling. Data were collected from focus groups, in-depth interviews, field notes, and observations. The findings indicated that although the women were happy to have Western maternity care, they valued the social and spiritual support received from bidan kampungs during pregnancy and postnatal care. Western care was considered useful for "modern" illnesses. The traditional maternity care that women received included pantang or ritual prohibitions that helped them through pregnancy and helped them achieve better postnatal recovery. The study indicates that there is a need to combine Western and traditional care for the benefit of the pregnant women and their infants' health.
Pathways to Male Transactional Sex in Mumbai, India.
Srivastava, Ankur; Goldbach, Jeremy T
2017-10-27
The article explores pathways to male transactional sex, focusing on entering, soliciting practices, role of pimps, client characteristics, and negotiations. Little scientific literature exists regarding male transactional sex in India, who represent a high-risk group for HIV infection. Case studies with 10 men who engage in transactional sex were conducted, who were recruited using purposive snowball sampling and interviewed at a social service organization. Participants differed in their sexual identity, sex roles, soliciting practices, and clients. Most of them listed economic crisis as their reason for entering transactional sex. Strategies to find clients included self-solicitation and referrals, while pimps played a major role in solicitation, negotiations, and events of crisis. The relationship among men who engage in transactional sex, pimps, and clients involves points of negotiation, opportunities, and limitations. HIV prevention should focus on identifying and addressing the groups' unique needs and working with pimps on risk-reduction strategies and crisis interventions.
Baseline Study of Women in South Africa with Postgraduate Physics Degrees (abstract)
NASA Astrophysics Data System (ADS)
Grayson, Diane J.
2009-04-01
A baseline study was conducted of women in South Africa who obtained BSc (Honours), MSc, or PhD degrees in physics and astronomy between 1995 and 2005. The first step involved identifying and contacting the women, using snowball sampling. These women were then asked to complete a questionnaire by e-mail. Responses to the questionnaire yielded information about the types of schools they attended, attitudes of their teachers, family history of studying science, influences on choosing to study physics, role models and mentors, employment history and aspects of a job that are important to them, experiences of gender bias, and suggestions for improving the situation for women in physics. This information is very valuable in designing programs, projects, and advocacy to encourage and retain women in physics, from school level to senior management. The methodology and questions developed can be useful to participants interested in obtaining similar information for their own countries.
Perception of Patients With HIV/AIDS From Stigma and Discrimination
Saki, Mandana; Mohammad Khan Kermanshahi, Sima; Mohammadi, Eesa; Mohraz, Minoo
2015-01-01
Background: Stigma and discrimination among patients with HIV/AIDS cause various problems for the patients and their health systems. Objectives: The purpose of this study was to explain the perceived experiences of the patients from stigma and discrimination and their roles on health-seeking services among patients. Patients and Methods: This was a qualitative research using content analysis approach and semi-structured interviews, conducted on patients living with HIV/ADS, during 2013 - 2014 in Iran. Sampling started purposefully and continued in a snowball. Results: The experiences of patients with HIV/AIDS from stigma and discrimination led to exploring three main themes and nine subthemes. The main themes were multidimensional stigma, rejection, and insult and discrimination in receiving health services. Conclusions: Stigma and discrimination play an important role in patients' lives and hinder them from accessing the treatment. The patients' responses to this event by secrecy strategy can be an important factor in the disease prevalence. PMID:26290751
Germani, Tamara; Zwaigenbaum, Lonnie; Magill-Evans, Joyce; Hodgetts, Sandy; Ball, Geoff
2017-11-01
To determine (a) the essential components of social participation for preschool children with Autism Spectrum Disorder (ASD) using stakeholders' perspectives and (b) the facilitators and barriers experienced in promoting social participation. A mixed-methods, web-based survey utilizing the International Classification of Functioning, Disability and Health - Child and Youth version (ICF-CY) taxonomy was circulated across Canada through purposeful snowball sampling. Frequency analysis of the combined responses of 74 stakeholders revealed the most essential components of social participation were: (a) behavior management, (b) social interactions, and (c) various types of play. Further, content analysis revealed that stakeholders used intrinsic motivation strategies and contingency management to facilitate social participation. Stakeholders reported that the purpose of social participation was to engage the child in fun, enjoyable social activities that developed relationships between the child and peers and created a sense of belonging in the community.
The essence of helping: significant others and nurses in action draw men into nursing.
Juliff, Dianne; Russell, Kylie; Bulsara, Caroline
2017-04-01
Nurses are ageing placing nursing workforce sustainability under threat. An untapped potential resource of men in nursing exists within Australia. The aim of the first phase of this longitudinal study was to investigate why men choose nursing. Qualitative methodological approach used interpretative phenomenological analysis (IPA). "What are the experiences of male graduate nurses regarding their career choice?" The IPA method focused on personal subjective experience where the participants' own sense-making is important. Discussions were audio-recorded, transcribed verbatim and analysed using a format relevant to IPA. Purposeful snowball sampling recruited nine nurses. The "essence of helping" permeated the key theme through significant others and career choice triggers impacting on their decision to enter nursing. Exposure to nurses in action is purported to enhance the awareness of nursing as a career option for men that may contribute to increased recruitment of men into nursing.
Health-Needs Assessment for West African Immigrants in Greater Providence, RI.
Adu-Boahene, Akosua Boadiwaa; Laws, Michael Barton; Dapaah-Afriyie, Kwame
2017-01-06
African immigrants in the United States may experience barriers to health-care access and effectiveness. This mixed-methods study used paper-based surveys of people (N=101) in the target population from Nigeria, Ghana, and Liberia, recruited through convenience and snowball sampling. Semi-structured interviews were conducted with 3 clergy members who pastor churches with large Nigerian, Ghanaian, and Liberian populations, respectively; and five physicians and a clinical pharmacist who serve African immigrants. Length of stay in the United States was associated with the health status of refugee children. Undocumented immigration status was associated with lack of health insurance. Cardiovascular diseases, uterine fibroids and stress-related disorders were the most prevalent reported conditions. Regardless of English fluency, many immigrants are unfamiliar with medical terminology. African immigrants in the state of Rhode Island need more health education and resources to navigate the US health-care system. [Full article available at http://rimed.org/rimedicaljournal-2017-01.asp].
'Individualism-collectivism' as an explanatory device for mental illness stigma.
Papadopoulos, Chris; Foster, John; Caldwell, Kay
2013-06-01
The aim of this study is investigate whether the cross-cultural value paradigm 'individualism-collectivism' is a useful explanatory model for mental illness stigma on a cultural level. Using snowball sampling, a quantitative questionnaire survey of 305 individuals from four UK-based cultural groups (white-English, American, Greek/Greek Cypriot, and Chinese) was carried out. The questionnaire included the 'Community Attitudes to Mental Illness scale' and the 'vertical-horizontal individualism-collectivism scale'. The results revealed that the more stigmatizing a culture's mental illness attitudes are, the more likely collectivism effectively explains these attitudes. In contrast, the more positive a culture's mental illness attitudes, the more likely individualism effectively explains attitudes. We conclude that a consideration of the individualism-collectivism paradigm should be included in any future research aiming to provide a holistic understanding of the causes of mental illness stigma, particularly when the cultures stigmatization levels are particularly high or low.
Older lesbian sexuality: identity, sexual behavior, and the impact of aging.
Averett, Paige; Yoon, Intae; Jenkins, Carol L
2012-01-01
In response to the very limited and mostly outdated literature on older lesbian sexuality, this exploratory study examined older lesbian sexual identity, romantic relationships, the impact of aging, and experiences of discrimination within these contexts. Utilizing an online survey that recruited via numerous online lesbian communities and snowball sampling, 456 lesbians over the age of 50 responded to closed, Likert scale, and open-ended questions that provided a preliminary understanding of older lesbian sexuality. The results indicated that older lesbians have experienced fluidity in past romantic and sexual relationships, as well as in erotic fantasies, despite strong identification with being lesbian. The findings also indicate a decreased focus on sexuality in the context of relationships, with more focus on stability and continuity. Future research is needed that provides greater specificity and detail about older lesbian conceptions of sexual behavior and sexual identity labels, as well as specific sexual behaviors.
Yu, Juping
2007-03-01
This paper explores the influence of ethnicity on attitudes towards sexual behavior of British-born Chinese teenagers. Using an ethnographic approach and snowball sampling, data were collected through in-depth interviews with 20 British-born Chinese teenagers and 20 Chinese-born parents. The parents highlighted the influence of Chinese culture and religion on their sexual values and wanted to convey these values to their children. Although direct communication about sex-related topics was rare within these families because of a number of barriers, the parents used other strategies to pass on their values. The paper concludes that sexual values within families and the influence of culture need to be considered in order to provide culturally competent health services. Chinese parents need extra support and help to discuss sex-related topics and pass on their values, which encourage teenage sexual abstinence. Considering the fundamental influence of the parents, this support will be crucial.
Using Facebook and LinkedIn to Recruit Nurses for an Online Survey.
Stokes, Yehudis; Vandyk, Amanda; Squires, Janet; Jacob, Jean-Daniel; Gifford, Wendy
2017-11-01
Social media is an emerging tool used by researchers; however, limited information is available on its use for participant recruitment specifically. The purpose of this article is to describe the use of Facebook and LinkedIn social media sites in the recruitment of nurses for an online survey, using a 5-week modified online Dillman approach. Within 3 weeks, we exceeded our target sample size ( n = 170) and within 5 weeks recruited 267 English-speaking nurses ( n = 172, Facebook; n = 95, LinkedIn). Advantages included speed of recruitment, cost-efficiency, snowballing effects, and accessibility of the researcher to potential participants. However, an analysis of the recruited participants revealed significant differences when comparing the sociodemographics of participants recruited through Facebook and LinkedIn, specifically relating to the characteristics of sex, age, and level of education. Differences between Facebook and LinkedIn as recruitment platforms should be considered when incorporating these strategies.
El Abani, Suaad; Pourmehdi, Mansour
2018-02-01
Domestic violence against women (DVAW) is a worldwide phenomenon and refers to any act committed against women that results in physical and psychological harm, and coercion, loss of liberty, and deprivation. There is a dearth of research and information about the extent and prevalence of domestic violence among Libyan communities. The aim of the study was to explore community knowledge of, and attitudes toward, DVAW and to improve our understanding of the factors that influence knowledge, attitudes, and responses, particularly educational and gender differences. Using snowball sampling, we analyzed 20 semistructured interviews with Libyans living in Manchester, United Kingdom. We found gender and education-influenced participants' perception of DVAW. Men in general did not recognize DVAW as a serious social problem; noticeably, they saw it as a personal and family issue. Knowing attitudes toward DVAW is necessary for government and communities' prevention policies as attitudes influence perpetration of DVAW.
McLoughlin, Gabriella; Weisman Fecske, Courtney; Castaneda, Yvette; Gwin, Candace; Graber, Kim
2017-10-01
There are many reasons why individuals are motivated to participate in sports. Less attention, however, is given for studying motivation and athlete development in adapted sport. The purpose of this study was to identify the motivations, facilitators, and barriers to sports participation of elite athletes with a physical disability. Participants (N = 23, 17 males, six females, mean age: 24.3 years) were recruited through online listservs, e-mails, and snowball sampling. A semistructured interview guide was employed. Analysis was conducted and grounded in self-determination theory and literature surrounding barriers and facilitators of sports participation. Through coding by multiple researchers, six themes emerged. Themes indicated that athletes attributed participation to constructs of self-determination theory as well as overcoming specific barriers such as cost, time constraints, and lack of opportunity. Among facilitators to their athletic development, there were empowerment and advocacy, increased health, college scholarships, and achieving performance-related goals.
Technology-enhanced learning in transnational higher education.
Arunasalam, Nirmala
2016-11-24
Some university schools of nursing in Australia and the UK have developed collaborative links with Malaysia to deliver part-time Transnational Higher Education (TNHE) post-registration top-up nursing degree courses. It enables nurses trained to diploma level to upgrade to a degree qualification. The views of 18 Malaysian nurses who had studied with one Australian and two UK TNHE universities were explored using a hermeneutic phenomenological approach. Participants recruited via convenience and snowball sampling methods were interviewed in English and Bahasa Malaysia (Malaysian language). Thematic analysis were used to analyse data. Findings indicated nurses' frustration with technology-enhanced teaching and learning and a lack of support throughout the programme. Although nurses developed confidence in using computer technology, they remained disappointed with the level of academic support. The data and some useful strategies outlined provide important insights for TNHE providers, the Malaysian Nursing Board and private hospital employers to consider for enhancing nurses learning and experiences.
Gregg, Jessica; Nguyen-Truong, Connie K Y; Wang, Pei-ru; Kobus, Amy
2011-12-01
Few studies have investigated what Vietnamese American women believe about the Pap smear or how those beliefs might influence behavior. Thirty-one Vietnamese American women recruited through snowball sampling were interviewed about their beliefs regarding the Pap smear. Interviews were qualitatively analyzed using a theoretically informed, inductive approach. The women interviewed emphasized the importance of primary prevention of disease through culturally-informed personal health regimens. They were also largely unfamiliar with the Pap smear, but believed that gynecological exams in general were effective and necessary for disease detection. Finally, when access to gynecological care was difficult, women's faith in their own preventive behaviors helped alleviate their concerns over lack of care. While culturally associated beliefs do not simply "cause" Vietnamese American women to seek or avoid Pap smears, they do influence screening behaviors to a greater or lesser degree, depending on other contextual variables.
Berthold, S Megan; Loomis, Alysse Melville; Kuoch, Theanvy; Scully, Mary; Hin-McCormick, Mui Mui; Casavant, Bryce; Buckley, Thomas
2018-05-23
Studies of relatively recently resettled refugees have noted social disconnection, linked to various physical and mental health outcomes, as a concern. Limited studies have examined whether social disconnection and its effects persists within refugee populations resettled more than 3 decades prior. The relationship between social disconnection and self-reported health was explored in a secondary analysis of a cross-sectional needs assessment survey with a snowball sample of 100 Cambodian refugees residing in Connecticut. Social disconnectedness and comorbid health conditions were prevalent. Lack of religious and community engagement were associated with poor health outcomes, while individuals with a lack of ethnic engagement reported better overall health. This study underscores the importance of understanding the specific risks that social disconnection poses to refugees who have resettled many years before and their offspring that may assist in better serving currently settling refugees within the United States.
Comets: Dirty snowballs or icy dirtballs
NASA Astrophysics Data System (ADS)
Keller, H. U.
1989-12-01
The observations of comet Halley show that the non-volatile (dust) component of the cometary nucleus has become more dominant if compared to the perception based on the icy conglomerate nucleus. The in-situ observations on the Giotto spacecraft revealed an excess of large dust particles that dominate the mass distribution. Even larger particles were derived from the attitude changes of the spacecraft bridging the gap to the cloud of particles observed by radar techniques. A dust to gas ratio larger than one was derived for comet Halley. The importance of dust for the structure of the nucleus is corroborated by the amount of particles and their lifetime in meteor streams. Fireballs show that large (meter size) objects separate from the nucleus and are stable enough to survive hundreds of orbital periods. From the various lines of evidence it is concluded that the structure of cometary nuclei is determined by the non-volatile component rather than by ice or snow. Laboratory models based on icy agglomerations do not seem realistic as nucleus analogs.
McKee, Michael B; Picciano, Joseph F; Roffman, Roger A; Swanson, Fred; Kalichman, Seth C
2006-04-01
Designing effective marketing and recruitment strategies for HIV prevention research requires attention to cultural relevance, logistical barriers, and perceived psychosocial barriers to accessing services. McGuire's communication/persuasion matrix (1985) guided our evaluation, with particular attention to success of each marketing "channel" (i.e., strategy) vis-à-vis the number of all callers, eligible callers, and enrolled callers, as well as reaching so-called "hard-to-serve" individuals. Nearly all channels offered success in reaching specific subgroups. Latinos responded favorably to posters, bisexuals responded favorably to paid media in an alternative (non-gay) publication, and precontemplators responded to referrals by family and friends. Although multiple recruitment strategies were used, three were crucial to the success of the project: (a) recruiters' presence in gay venues, (b) referrals by family and friends (snowball technique), and (c) paid advertisements in alternative (non-gay) local newspapers. Resource allocation and costs are also presented for each channel.
Tartakovsky, Eugene; Abu Kheit, Ayat
2017-01-01
The present study investigates the connection between personal value preferences, group identifications, and cultural practices among Palestinian Israelis working in close contact with the Jewish population in Israel. One hundred twenty-two Palestinian Israelis participated in the study. The participants were employed in different professional positions in the Tel Aviv Metropolitan area and were recruited to the study using the snowball technique. A stronger national identification was associated with a higher preference for the security and conformity values, and a lower preference for the humility values. A stronger ethnic identification was associated with a lower preference for the security, power, and stimulation values. Group identifications mediated the connection between personal value preferences and cultural practices. A longer time working in close contact with the majority group and less frequent visits home were associated with a greater adherence to the majority group's cultural practices but not with adherence to the ethnic group's practices and not with the group identifications.
The Snowball Blizzard Incident: A Reality Rub Life Space Interview.
ERIC Educational Resources Information Center
Long, Nicholas J.; Pinciotti, Dennis
1992-01-01
Focuses on Reality Rub Interview, one type of Life Space Interview (LSI), effective intervention strategy for use during crisis work with troubled students. Presents actual Reality Rub Interview, used with students who have "social blindness, social myopia, and tunnel vision" and who, when upset, misinterpret words and behaviors of…
Ramakrishnan, Parameshwaran; Baccari, Andrew; Ramachandran, Uma; Ahmed, Syed Faiz; Koenig, Harold G
2017-08-17
Religious-spiritual (R/S) education helps medical students cope with caregiving stress and gain skills in interpersonal empathy needed for clinical care. Such R/S education has been introduced into K-12 and college curricula in some developed nations and has been found to positively impact student's mental health. Such a move has not yet been seen in the Indian education system. This paper aimed to examine perspectives of teachers and parents in India on appropriateness, benefits, and challenges of including R/S education into the school curriculum and also to gather their impressions on how a R/S curriculum might promote students' health. A cross-sectional study of religiously stratified sample of teachers and parents was initiated in three preselected schools in India and the required sample size (N = 300) was reached through snowballing technique. A semi-structured questionnaire, with questions crafted from "Religion and Spirituality in Medicine, Physicians Perspective" (RSMPP) and "American Academy of Religion's (AAR) Guidelines for Religious Literacy," was used to determine participants' perspectives. Findings revealed that teachers' and parents' "comfort in integrating R/S into school curriculum" was associated with their gender (OR 1.68), education status (OR 1.05), and intrinsic religiosity (OR 1.05). Intrinsic religiosity was significantly (p = 0.025) high among parents while "intrinsic spirituality" was high (p = 0.020) among teachers. How participants' R/S characteristics influence their support of R/S education in school is discussed. In conclusion, participants believe R/S education will fosters students' emotional health and interpersonal skills needed for social leadership. A curriculum that incorporates R/S education, which is based on AAR guidelines and clinically validated interpersonal spiritual care tools would be acceptable to both teachers and parents.
Wynne-Jones, Gwenllian; van der Windt, Danielle; Ong, Bie Nio; Bishop, Annette; Cowen, Jemma; Artus, Majid; Sanders, Tom
2014-06-18
Musculoskeletal complaints have a significant impact on work in terms of reduced productivity, sickness absence and long term incapacity for work. This study sought to explore GPs' and physiotherapists' perceptions of sickness certification in patients with musculoskeletal problems. Eleven (11) GPs were sampled from an existing general practice survey, and six (6) physiotherapists were selected randomly using 'snowball' sampling techniques, through established contacts in local physiotherapy departments. Semi-structured qualitative interviews were conducted with respondents lasting up to 30 minutes. The interviews were audio recorded and transcribed verbatim, following which they were coded using N-Vivo qualitative software and analysed thematically using the constant comparative methodology, where themes were identified and contrasted between and within both groups of respondents. Three themes were identified from the analysis: 1) Approaches to evaluating patients' work problems 2) Perceived ability to manage 'work and pain', and 3) Policies and penalties in the work-place. First, physiotherapists routinely asked patients about their job and work difficulties using a structured (protocol-driven) approach, whilst GPs rarely used such structured measures and were less likely to enquire about patients' work situation. Second, return to work assessments revealed a tension between GPs' gatekeeper and patient advocacy roles, often resolved in favour of patients' concerns and needs. Some physiotherapists perceived that GPs' decisions could be influenced by patients' demand for a sick certificate and their close relationship with patients made them vulnerable to manipulation. Third, the workplace was considered to be a specific source of strain for patients acting as a barrier to work resumption, and over which GPs and physiotherapists could exercise only limited control. We conclude that healthcare professionals need to take account of patients' work difficulties, their own perceived ability to offer effective guidance, and consider the 'receptivity' of employment contexts to patients' work problems, in order to ensure a smooth transition back to work.
Dallora, Ana Luiza; Eivazzadeh, Shahryar; Mendes, Emilia; Berglund, Johan; Anderberg, Peter
2017-01-01
Dementia is a complex disorder characterized by poor outcomes for the patients and high costs of care. After decades of research little is known about its mechanisms. Having prognostic estimates about dementia can help researchers, patients and public entities in dealing with this disorder. Thus, health data, machine learning and microsimulation techniques could be employed in developing prognostic estimates for dementia. The goal of this paper is to present evidence on the state of the art of studies investigating and the prognosis of dementia using machine learning and microsimulation techniques. To achieve our goal we carried out a systematic literature review, in which three large databases-Pubmed, Socups and Web of Science were searched to select studies that employed machine learning or microsimulation techniques for the prognosis of dementia. A single backward snowballing was done to identify further studies. A quality checklist was also employed to assess the quality of the evidence presented by the selected studies, and low quality studies were removed. Finally, data from the final set of studies were extracted in summary tables. In total 37 papers were included. The data summary results showed that the current research is focused on the investigation of the patients with mild cognitive impairment that will evolve to Alzheimer's disease, using machine learning techniques. Microsimulation studies were concerned with cost estimation and had a populational focus. Neuroimaging was the most commonly used variable. Prediction of conversion from MCI to AD is the dominant theme in the selected studies. Most studies used ML techniques on Neuroimaging data. Only a few data sources have been recruited by most studies and the ADNI database is the one most commonly used. Only two studies have investigated the prediction of epidemiological aspects of Dementia using either ML or MS techniques. Finally, care should be taken when interpreting the reported accuracy of ML techniques, given studies' different contexts.
Mendes, Emilia; Berglund, Johan; Anderberg, Peter
2017-01-01
Background Dementia is a complex disorder characterized by poor outcomes for the patients and high costs of care. After decades of research little is known about its mechanisms. Having prognostic estimates about dementia can help researchers, patients and public entities in dealing with this disorder. Thus, health data, machine learning and microsimulation techniques could be employed in developing prognostic estimates for dementia. Objective The goal of this paper is to present evidence on the state of the art of studies investigating and the prognosis of dementia using machine learning and microsimulation techniques. Method To achieve our goal we carried out a systematic literature review, in which three large databases—Pubmed, Socups and Web of Science were searched to select studies that employed machine learning or microsimulation techniques for the prognosis of dementia. A single backward snowballing was done to identify further studies. A quality checklist was also employed to assess the quality of the evidence presented by the selected studies, and low quality studies were removed. Finally, data from the final set of studies were extracted in summary tables. Results In total 37 papers were included. The data summary results showed that the current research is focused on the investigation of the patients with mild cognitive impairment that will evolve to Alzheimer’s disease, using machine learning techniques. Microsimulation studies were concerned with cost estimation and had a populational focus. Neuroimaging was the most commonly used variable. Conclusions Prediction of conversion from MCI to AD is the dominant theme in the selected studies. Most studies used ML techniques on Neuroimaging data. Only a few data sources have been recruited by most studies and the ADNI database is the one most commonly used. Only two studies have investigated the prediction of epidemiological aspects of Dementia using either ML or MS techniques. Finally, care should be taken when interpreting the reported accuracy of ML techniques, given studies’ different contexts. PMID:28662070
NASA Astrophysics Data System (ADS)
Gyollai, I.; Popp, F.; Mader, D.; Koeberl, Ch.
2012-04-01
Introduction The so-called "Snowball Earth hypothesis" states that the "Sturtian" (710 Ma) and "Marinoan" glaciations (635 Ma) were of global extent and may have lasted for several million years. Our samples were collected from conspicuous transition layers on top of the glaciogenic Chuos (Sturtian) (10 samples) and Ghaub (Marinoan) formations (63 samples) of the Neoproterozoic Otavi Group in NW-Namibia. The goal of this study is to obtain information concerning the provenance and geochemical composition of postglacial diamictite/cap carbonate transition layers and to estimate the paleoenvironmental conditions with respect to glacio-marine sea water composition and attendant sediment accumulation in mineralogical-geochemical aspects. Methods The mineralogical composition of our samples was studied using the petrographic microscope, X-ray powder diffraction, cathodoluminescence microscopy, and micro-Raman spectrometry. Instrumental neutron activation and X-ray fluorescence analyses, as well as analytical electron microscopy, were used for the geochemical study. Results Detrital components derived from crystalline and/or dolomite platform source areas are enclosed within a diagenetically recrystallized matrix of carbonate and quartz minerals. Clay samples from both, Marinoan and some Sturtian postglacial layers are characterized by high Ni/Co, Cr/V, and low Th/Sc, La/Sc, V/Ni and Cr/Ni ratios compared to PAAS (Postarchean Australian shale, [1]), which could indicate mafic-ultramafic source material[1]. According to SEM-EDX measurements, only hematite, quartz, and feldspar make up the detrital composition, thus the Cr-Ni enrichment does not seem to be associated with any specific mineral phases. Specific results for the Sturtian postglacial transition layers: An U/Th ratio >0.75, and Mo-enrichment in the topmost iron-rich Sturtian diamictites (Chuos Fm.) and their superposed postglacial boundary layers (Rasthof Fm) indicates reducing conditions in the sea water [2,3 ]. The detritus of the basal cap carbonates is rich in kaolinite and montmorillonite and has low K/Cs values, indicating a high weathering rate. Specific results for the Marinoan postglacial transition layers: The Marinoan diamictites (Ghaub Fm.) and their superposed postglacial transition layers (basal Maieberg Fm) are characterized in a few cases by very high Th/Co, Th/Sc and LREE/HREE ratios, which indicate some influence of a felsic source area. The detrital/recrystallized components of these iron-poor diamictites are rich in pyrite and quartz and display a REE enrichment compared to PAAS, which indicates a hydrothermal component during their accumulation [3]. Conlusions 1) Sturtian layers: possibly different source areas supplied the sedimentary basins 2) Marinoan layers : sediments were influenced by hydrothermal fluids and diagenetic alteration 3) Reducing conditions existed in the marine environment during both of the "Snowball Earth" glaciation periods each followed by oxidative conditions reflected in the geochemical composition of related postglacial cap carbonates. Acknowledgement Our work is funded by the Austrian Academy of Sciences (IGCP 512) (to CK).
Ethnomedicines used in Trinidad and Tobago for reproductive problems
Lans, Cheryl
2007-01-01
Background Throughout history women have tried to control or enhance their fertility using herbal remedies, with various levels of societal support. Caribbean folk medicine has been influenced by European folk medicine, either through the early Spanish and French settlers or through the continuous immigration of Spanish-speaking peoples from Venezuela. Some folk uses are ancient and were documented by Galen and Pliny the Elder. Methods Thirty respondents, ten of whom were male were interviewed from September 1996 to September 2000. The respondents were obtained by snowball sampling, and were found in thirteen different sites, 12 in Trinidad (Paramin, Talparo, Sangre Grande, Mayaro, Carapichaima, Kernahan, Newlands, Todd's Road, Arima, Guayaguayare, Santa Cruz, Port of Spain and Siparia) and one in Tobago (Mason Hall). Snowball sampling was used because there was no other means of identifying respondents and to cover the entire islands. The validation of the remedies was conducted with a non-experimental method. Results Plants are used for specific problems of both genders. Clusea rosea, Urena sinuata and Catharanthus roseus are used for unspecified male problems. Richeria grandis and Parinari campestris are used for erectile dysfunction. Ageratum conyzoides, Scoparia dulcis, Cucurbita pepo, Cucurbita maxima, Gomphrena globosa and Justicia pectoralis are used for prostate problems. The following plants are used for childbirth and infertility: Mimosa pudica, Ruta graveolens, Abelmoschus moschatus, Chamaesyce hirta, Cola nitida, Ambrosia cumanenesis, Pilea microphylla, Eryngium foetidum, Aristolochia rugosa, Aristolochia trilobata, Coleus aromaticus, Laportea aestuans and Vetiveria zizanioides. The following plants are used for menstrual pain and unspecified female complaints: Achyranthes indica, Artemisia absinthium, Brownea latifolia, Eleutherine bulbosa, Hibiscus rosa-sinensis, Eupatorium macrophyllum, Justicia secunda, Parthenium hysterophorus, Wedelia trilobata, Abelmoschus moschatus, Capraria biflora, Cordia curassavica, Croton gossypifolius, Entada polystachya, Leonotis nepetaefolia, Eryngium foetidum, Aristolochia rugosa, Aristolochia trilobata and Ambrosia cumanenesis. Conclusion Native Caribbean plants have been less studied that those from Africa, India and Europe. Chamaesyce hirta has scientific support but as a diuretic. Other plants with level 3 validity for reproductive issues are: Achyranthes indica, Coleus aromaticus, Hibiscus rosa-sinesis, Parthenium hysterophorus and Ruta graveolens. The non-experimental validation method can be used to advise the public on which plants are safe, effective and useful, and which are not; pending clinical trials. This is especially important since so few clinical trials are conducted on Caribbean plants. PMID:17362507
Ethnomedicines used in Trinidad and Tobago for reproductive problems.
Lans, Cheryl
2007-03-15
Throughout history women have tried to control or enhance their fertility using herbal remedies, with various levels of societal support. Caribbean folk medicine has been influenced by European folk medicine, either through the early Spanish and French settlers or through the continuous immigration of Spanish-speaking peoples from Venezuela. Some folk uses are ancient and were documented by Galen and Pliny the Elder. Thirty respondents, ten of whom were male were interviewed from September 1996 to September 2000. The respondents were obtained by snowball sampling, and were found in thirteen different sites, 12 in Trinidad (Paramin, Talparo, Sangre Grande, Mayaro, Carapichaima, Kernahan, Newlands, Todd's Road, Arima, Guayaguayare, Santa Cruz, Port of Spain and Siparia) and one in Tobago (Mason Hall). Snowball sampling was used because there was no other means of identifying respondents and to cover the entire islands. The validation of the remedies was conducted with a non-experimental method. Plants are used for specific problems of both genders. Clusea rosea, Urena sinuata and Catharanthus roseus are used for unspecified male problems. Richeria grandis and Parinari campestris are used for erectile dysfunction. Ageratum conyzoides, Scoparia dulcis, Cucurbita pepo, Cucurbita maxima, Gomphrena globosa and Justicia pectoralis are used for prostate problems. The following plants are used for childbirth and infertility: Mimosa pudica, Ruta graveolens, Abelmoschus moschatus, Chamaesyce hirta, Cola nitida, Ambrosia cumanenesis, Pilea microphylla, Eryngium foetidum, Aristolochia rugosa, Aristolochia trilobata, Coleus aromaticus, Laportea aestuans and Vetiveria zizanioides. The following plants are used for menstrual pain and unspecified female complaints: Achyranthes indica, Artemisia absinthium, Brownea latifolia, Eleutherine bulbosa, Hibiscus rosa-sinensis, Eupatorium macrophyllum, Justicia secunda, Parthenium hysterophorus, Wedelia trilobata, Abelmoschus moschatus, Capraria biflora, Cordia curassavica, Croton gossypifolius, Entada polystachya, Leonotis nepetaefolia, Eryngium foetidum, Aristolochia rugosa, Aristolochia trilobata and Ambrosia cumanenesis. Native Caribbean plants have been less studied that those from Africa, India and Europe. Chamaesyce hirta has scientific support but as a diuretic. Other plants with level 3 validity for reproductive issues are: Achyranthes indica, Coleus aromaticus, Hibiscus rosa-sinesis, Parthenium hysterophorus and Ruta graveolens. The non-experimental validation method can be used to advise the public on which plants are safe, effective and useful, and which are not; pending clinical trials. This is especially important since so few clinical trials are conducted on Caribbean plants.
NASA Astrophysics Data System (ADS)
Ling, H.-F.; Jiang, S.-Y.; Feng, H.-Z.; Chen, J.-H.; Chen, Y.-Q.; Yang, J.-H.
2003-04-01
Seawater and its isotopic composition is the most promising recorder for the climate change of the Earth. Chemical sediments such as carbonate and phosphorite has long been used to reveal the seawater chemistry in the past. The d13C of carbonate with least diagenesis has proved to be sensitive proxy for paleo-environment and paleo-productivity and for chemostratigrphy (e.g. Shen, 2002; Yang et al., 1999; Lambert et al., 1987). However, d18O of carbonate are more prone to suffering diagenesis, and therefore the implications of Phanerozoic d18O curve are controversial (cf. Veizer et al., 1999). Recent study of Wenzel et al. (2000) shows that Silurian phosphatic conodont retained primary oxygen isotopes whereas the d18O values of the coeval calcitic brachiopod shells were altered by diagenesis. Here, we presented and compared oxygen, carbon isotopic compositions and trace and rare earth element concentrations of Neoproterozoic phosphorite and coeval dolomite from the Yangtze platform in an attempt to reconstruct the paleoclimatological and paleooceanographic change during Neoproterozoic. The Yangtze platform possesses excellent record of Late Neoproterozoic-Cambrian strata. In this study, we collected samples systematically from late Neoproterozoic Doushantuo Formation at the Wengan section, Guizhou province. The Doushantuo Fm, overlying on the late Vendian tillite of Nantuo Fm and overlain by dolostone of Dengying Fm which underlain the basal Cambrian black shale, consists mainly of phosphorite and minor interbeded dolostone with total thickness of about 70 m. Our results show large variations of d18Odolo(SMOW) for the dolomite (17.6 ~ 25.9‰) which has no correlation with their d13Cdolo values and other geochemical parameters. In contrast, phosphorites display rather limited variations of the d18Ophos (SMOW) values (10.7 ~ 15.0‰). Further more, the d18Ophos and d13Cdolo values, Ce anomaly and Pb/Th ratio consistently increased from the lower to upper part of the section. It is suggested that the phosphorite studied preserved primary oxygen isotopes, whereas d18Odolo values of the dolomite were altered by diagenesis. Potential causes for the overall increase trend of d18Ophos include increase in seawater d18O values and decrease in temperature. During the time span of about 10 ~ 30 Ma for the section deposition when no glaciation occurred, it seems not completely in reality to attribute the variation of more than 4‰ of d18O values to seawater change alone. To cause ~4.3‰ variation of d18Ophos, temperature would decrease about 15-20˚C, which is possible to happen in the Earth history (Lecuyer and Allemand, 2002). The following lines of evidence also support this view. The studied phosphorites were deposited after thaw of the Snowball Earth. During the Snowball Earth period, continental weathering was in minimum due to little precipitation. This, together with existence of volcanic CO2 emitting through the snowball, CO2 accumulated in the atmosphere up to very high level and thus the temperature would be very high soon after thaw of the Snowball Earth. This, combined with more precipitation, would cause progressive weathering. Enhanced weathering of continental rocks would draw down the CO2 of atmosphere and in turn cause cooling, which is consistent with temperature lowering of the period. Increase trend of Pb/Th ratio during the period is in good agreement with enhanced weathering. Pb and Th are both highly particle reactive elements in the ocean. However, their geochemical behaviors in weathering processes are potentially different. Pb is mainly contained in feldspar while Th is mainly hosted in accessory minerals such as monazite. During enhanced weathering processes feldspar can be altered and release Pb whereas monazite would usually survive. Therefore Pb/Th ratio in hydrogenic sediments would be an indicator of weathering intensity. Enhanced weathering would also provide more nutrition elements to ocean, resulting in increase in productivity. The overall increasing trend of d13Cdolo agrees well with increasing productivity. Increased alga productivity would raise release of oxygen to the ocean by processes of photosynthesis, burial of light carbon and thus elevate heavy carbon in the ocean. This may also be the cause of increase in Ce anomaly. In conclusion, the above changes are consistent with each other. The overall increase trends of phosphorite d18O may imply decrease in temperature post the temperature maximum at thaw of the Snowball Earth.
Near-death states reported in a sample of 50 misusers.
Corazza, Ornella; Schifano, Fabrizio
2010-05-01
Increase in recreational ketamine use may be a cause for concern. We aimed here at assessing, in a sample of ketamine misusers, concordance between the typical near-death experience (NDE) features and the on-drug psychoactive effects the subjects experienced. In 2003-2005, a sample of previous ketamine misusers recollecting a ketamine-related NDE were recruited through snowballing and screened with the means of the Greyson NDE Scale; 125 participants made an initial contact with the researcher and 50 reported a minimum score of seven at the "Greyson NDE Scale". Interviewees were in the range 21-66 years old; 27 participants (54%) were educated at BA level, 18 (36%) had an MSc, and 5 (10%) a PhD. Eight (16%) interviewees had a definite religious background. An average lifetime ketamine intake of 140 occasions was reported by the interviewees, who typically presented with a polydrug, including cannabis and MDMA/ecstasy, misuse history. In 45 (90%) cases, the NDE occurred during the first few occasions of intake. Most frequent features of reported NDE states included: altered perception of time (90%), strong sense of detaching from own physical body (88%), and a sense of peace/joy (76% of subjects). Although results here described were elicited from a self-selected, nonrandomized, limited size sample of misusers, we suggest that recreational ketamine intake may be associated with occurrence of near-death related states.
No evidence of extraterrestrial noble metal and helium anomalies at Marinoan glacial termination
NASA Astrophysics Data System (ADS)
Peucker-Ehrenbrink, Bernhard; Waters, Christine A.; Kurz, Mark D.; Hoffman, Paul F.
2016-03-01
High concentrations of extraterrestrial iridium have been reported in terminal Sturtian and Marinoan glacial marine sediments and are used to argue for long (likely 3-12 Myr) durations of these Cryogenian glaciations. Reanalysis of the Marinoan sedimentary rocks used in the original study, supplemented by sedimentary rocks from additional terminal Marinoan sections, however, does not confirm the initial report. New platinum group element concentrations, and 187Os/188Os and 3He/4He signatures are consistent with crustal origin and minimal extraterrestrial contributions. The discrepancy is likely caused by different sample masses used in the two studies, with this study being based on much larger samples that better capture the stochastic distribution of extraterrestrial particles in marine sediments. Strong enrichment of redox-sensitive elements, particularly rhenium, up-section in the basal postglacial cap carbonates, may indicate a return to more fully oxygenated seawater in the aftermath of the Marinoan snowball earth. Sections dominated by hydrogenous osmium indicate increasing submarine hydrothermal sources and/or continental inputs that are increasingly dominated by young mantle-derived rocks after deglaciation. Sedimentation rate estimates for the basal cap carbonates yield surprisingly slow rates of a few centimeters per thousand years. This study highlights the importance of using sedimentary rock samples that represent sufficiently large area-time products to properly sample extraterrestrial particles representatively, and demonstrates the value of using multiple tracers of extraterrestrial matter.
Physician Evaluation of Internet Health Information on Proton Therapy for Prostate Cancer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shah, Anand, E-mail: as4351@columbia.edu; Department of Radiation Oncology, Columbia University Medical Center, New York, New York; Paly, Jonathan J.
Purpose: Many patients considering prostate cancer (PCa) treatment options report seeking proton beam therapy (PBT) based in part on information readily available on the Internet. There is, however, potential for considerable variation in Internet health information (IHI). We thus evaluated the characteristics, quality, and accuracy of IHI on PBT for PCa. Methods and Materials: We undertook a qualitative research study using snowball-purposive sampling in which we evaluated the top 50 Google search results for “proton prostate cancer.” Quality was evaluated on a 5-point scale using the validated 15-question DISCERN instrument. Accuracy was evaluated by comparing IHI with the best availablemore » evidence. Results: Thirty-seven IHI websites were included in the final sample. These websites most frequently were patient information/support resources (46%), were focused exclusively on PBT (51%), and had a commercial affiliation (38%). There was a significant difference in quality according to the type of IHI. Substantial inaccuracies were noted in the study sample compared with best available or contextual evidence. Conclusions: There are shortcomings in quality and accuracy in consumer-oriented IHI on PBT for PCa. Providers must be prepared to educate patients how to critically evaluate IHI related to PBT for PCa to best inform their treatment decisions.« less
[Status on sexual partners among men who have sex with men among college students in Qingdao, 2016].
Zhang, X F; Lyu, C X; Zheng, J T; Dong, L; Jiang, Z X; Fu, J H
2017-12-10
Objective: To investigate the situation of sexual partners and related factors among men who have sex with men (MSM) in college students. Methods: Snowball sampling and Convenience sampling were both used to recruit MSM from colleges in Tsingtao in 2016. Questionnaire-based interviews were conducted to collect data of socio-demographic and situation of sexual partners. Sample Size was estimated based on cross-sectional study, and theoretical 267. SPSS 17.0 software was used for statistical analysis. Results: A total of 300 MSM, average aged 20.7, were analyzed. Both first sex partner and the last same-sex sexual partner were met instantly, with proportions as 58.7% (176/300) and 62.3% (187/300) respectively. Among all the MSM, 88.3% (265/300) preferred selecting men as sex partners and 42.7% (128/300) enjoyed finding sex partners in college, while 86.0% (258/300) preferred finding their sex partners through internet. Conclusions: Internet had been the major way of looking for sex partner among MSM in college students, the male sexual partner were met instantly. We should focus on men who have sex with men and their sexual health among college students to prevent and control HIV/AIDS.
The Potential Skills Contribution of International Students to South Africa
ERIC Educational Resources Information Center
Aloyo, N.; Wentzel, A.
2011-01-01
There has been a significant increase in the number of international students, especially in those from other African countries, at South African universities over the last ten years. This has elicited some research, notably from Ramphele, Crush and McDonald (1999); Hall (2004); and Snowball and Antrobus (2005; 2006). However, none of these…
More than an Intervention: Strategies for Increasing Diversity and Inclusion in STEM
ERIC Educational Resources Information Center
Jones, Sosanya
2016-01-01
Purpose: This paper aims to provide insight into the strategies used by leaders of graduate school preparation programs for science, technology, engineering and mathematics (STEM) to recruit and retain graduate students of color within STEM fields. Design/methodology/approach: This paper is a qualitative multiple-case study using a snowball sample…
Sansjofre, Pierre; Cartigny, Pierre; Trindade, Ricardo I. F.; Nogueira, Afonso C. R.; Agrinier, Pierre; Ader, Magali
2016-01-01
The terminal Neoproterozoic Era (850–542 Ma) is characterized by the most pronounced positive sulfur isotope (34S/32S) excursions in Earth's history, with strong variability and maximum values averaging δ34S∼+38‰. These excursions have been mostly interpreted in the framework of steady-state models, in which ocean sulfate concentrations do not fluctuate (that is, sulfate input equals sulfate output). Such models imply a large pyrite burial increase together with a dramatic fluctuation in the isotope composition of marine sulfate inputs, and/or a change in microbial sulfur metabolisms. Here, using multiple sulfur isotopes (33S/32S, 34S/32S and 36S/32S ratios) of carbonate-associated sulfate, we demonstrate that the steady-state assumption does not hold in the aftermath of the Marinoan Snowball Earth glaciation. The data attest instead to the most impressive event of oceanic sulfate drawdown in Earth's history, driven by an increased pyrite burial, which may have contributed to the Neoproterozoic oxygenation of the oceans and atmosphere. PMID:27447895
Brocks, J J; Jarrett, A J M; Sirantoine, E; Kenig, F; Moczydłowska, M; Porter, S; Hope, J
2016-03-01
The period 800-717 million years (Ma) ago, in the lead-up to the Sturtian Snowball glaciation, saw an increase in the diversity of eukaryotic microfossils. To afford an independent and complementary view of this evolutionary period, this study presents the distribution of eukaryotic biomarkers from three pre-Sturtian successions across the supercontinent Rodinia: the ca. 780 Ma Kanpa Formation of the Western Australian Officer Basin, the ca. 800-740 Ma Visingsö Group of Sweden, and the 740 Ma Chuar Group in Arizona, USA. The distribution of eukaryotic steranes is remarkably similar in the three successions but distinct from all other known younger and older sterane assemblages. Cholestane was the only conventional structure, while indigenous steranes alkylated in position C-24, such as ergostane, stigmastane, dinosterane and isopropylcholestane, and n-propylcholestane, were not observed. This sterane distribution appears to be age diagnostic for the pre-Sturtian Neoproterozoic. It attests to the distinct evolutionary state of pre-Snowball eukaryotes, pointing to a taxonomic disparity that was still lower than in the Ediacaran (635-541 Ma). All three basins also show the presence of a new C28 sterane that was tentatively identified as 26-methylcholestane, here named cryostane. The only known extant organisms that can methylate sterols in the 26-position are demosponges. This assignment is plausible as molecular clocks place the appearance of the earliest animals into the pre-Sturtian Neoproterozoic. The unusual 26-methylsterol may have protected sponges, but also other eukaryotes, against their own membranolytic toxins. Some protists release lytic toxins to deter predators and kill eukaryotic prey. As conventional membrane sterols can be the site of attack for these toxins, sterols with unusual side-chain modification protect the cell. This interpretation of cryostane supports fossil evidence of predation in the Chuar Group and promotes hypotheses about the proliferation of eukaryophagy in the lead-up to the Cryogenian. © 2015 John Wiley & Sons Ltd.
HABITABLE CLIMATES: THE INFLUENCE OF ECCENTRICITY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dressing, Courtney D.; Spiegel, David S.; Scharf, Caleb A.
2010-10-01
In the outer regions of the habitable zone, the risk of transitioning into a globally frozen 'snowball' state poses a threat to the habitability of planets with the capacity to host water-based life. Here, we use a one-dimensional energy balance climate model (EBM) to examine how obliquity, spin rate, orbital eccentricity, and the fraction of the surface covered by ocean might influence the onset of such a snowball state. For an exoplanet, these parameters may be strikingly different from the values observed for Earth. Since, for a constant semimajor axis, the annual mean stellar irradiation scales with (1 - emore » {sup 2}){sup -1/2}, one might expect the greatest habitable semimajor axis (for fixed atmospheric composition) to scale as (1 - e {sup 2}){sup -1/4}. We find that this standard simple ansatz provides a reasonable lower bound on the outer boundary of the habitable zone, but the influence of both obliquity and ocean fraction can be profound in the context of planets on eccentric orbits. For planets with eccentricity 0.5, for instance, our EBM suggests that the greatest habitable semimajor axis can vary by more than 0.8 AU (78%) depending on obliquity, with higher obliquity worlds generally more stable against snowball transitions. One might also expect that the long winter at an eccentric planet's apoastron would render it more susceptible to global freezing. Our models suggest that this is not a significant risk for Earth-like planets around Sun-like stars, as considered here, since such planets are buffered by the thermal inertia provided by oceans covering at least 10% of their surface. Since planets on eccentric orbits spend much of their year particularly far from the star, such worlds might turnout to be especially good targets for direct observations with missions such as TPF-Darwin. Nevertheless, the extreme temperature variations achieved on highly eccentric exo-Earths raise questions about the adaptability of life to marginally or transiently habitable conditions.« less
Working in the Shadows: Safety and Health in Forestry Services in Southern Oregon
Wilmsen, Carl; Bush, Diane; Barton-Antonio, Dinorah
2018-01-01
We conducted a small participatory survey to document occupational injuries and illnesses, medical treatment, wage issues, and general working conditions among 150 forest workers in southern Oregon who are mostly Spanish-speaking immigrants from Latin America. We used snowball sampling in administering the survey. Survey results showed a high rate of job-related injury among the workers who responded to our survey. Results also suggested that many forestry services contractors licensed in Jackson and Josephine counties may not always follow labor laws. The vast majority of workers surveyed reported being fearful of retaliation for reporting injuries. There were no differences in reported working conditions and wage issues between workers with H-2B visas and other workers in the sample. This finding suggests that current US labor and health and safety laws are not effectively protecting Oregon’s forest workers, owing to forest workers’ structural vulnerability—their low positioning in social structures supported by immigration and economic status—compounded by fear of retaliation. Immigration policies and enforcement practices that contribute to creating a labor system with these inherent vulnerabilities and power imbalances need to be further examined and changed. PMID:29643572
Finding common ground: perspectives on community-based childhood obesity prevention.
Porter, Christine M; Pelletier, David L
2012-11-01
To support successful and inclusive community organizing for childhood obesity prevention, this research identified stakeholder perspectives on what communities should do to prevent childhood obesity. It employed factor analysis on statement sorts (Q methodology) conducted by 95 people in an upstate New York community. These participants sorted 36 statements about the issue by how much he or she agreed or disagreed with each. Participants were recruited through strategic snowball sampling to sample a variety of perspectives. The four resulting factors, or perspectives, were interpreted in the context of presort demographic surveys and postsort interviews. This research found one stance that fits the environmental perspective common in public health. The other three factors indicate important variations among perspectives centered on individual responsibility, ranging from libertarian to technocratic views. However, overall, results revealed a substantial degree of agreement among the four perspectives, including on providing access to family activities and on making fruits and vegetables more available and affordable, for example, through subsidies. This article points to common ground for community action on childhood obesity prevention, highlights areas likely to generate considerable contention, and shows whose views are not being accounted for in, at least, this community's childhood obesity prevention project.
Mental health and individual experience of unemployed young adults in Japan
KITO, Aiko; UENO, Takeji
2015-01-01
This study focused on the subjective experiences and mental health of young, unemployed adults in Japan. We explored how individuals describe their experiences of becoming unemployed and how these experiences influence their mental health within the current Japanese sociocultural context, using a social constructionist approach. We collected data from October 2012 to January 2013. Participants were 25 young unemployed Japanese job seekers (15 females), who were recruited using a purposive sampling strategy including snowball sampling. We conducted semi-structured interviews focusing on participants’ previous work and job search experience, their lifestyle and health, the social support they considered necessary, their future job-seeking plans, and their demographic characteristics. Using thematic analysis, we identified four key themes from the interview data: stress relief, re-energization for future work, new job skills acquisition, and lifestyle change. The findings indicate that unemployment is sometimes experienced as more beneficial than employment. This might be because of the poor working environment in Japan, the financial support participants received, and the experience of short-term unemployment. The findings suggest that intervention is necessary to help young adults in Japan find high-quality jobs and that we must promote fair employment and decent working conditions for them. PMID:26320730
NASA Astrophysics Data System (ADS)
Yuniastuti, E.; Anggita, A.; Nandariyah; Sukaya
2018-03-01
The characteristics durian based on specific area gives a wide diversity of phenotype. This research objective was to build an inventory of the local durian of Ngrambe as well as to obtain potentially superior local durian as prospective parent trees. The research was conducted in Ngrambe sub-district, on October 2015 until April 2016 using the explorative descriptive method. The determination of sample point used the non-probability method of snowball sampling type. Primary data include the morphology of plant characters, trunks, leaves, flower, fruits and seeds and their superiority. The data of the research were analyzed using SIMQUAL (Similarity for Qualitative) function based on the DICE coefficient on NTSYS v.2.02. The data cluster and dendrogram analyses were determined by Unweighted Pair-Group Arithmetic Average (UPGMA) method. The result of DICE coefficient analyses of 58 local durian accession based on the phenotypic character of vegetative organs ranged from 0.84-1.0. The phenotypic character of the vegetative and generative organ from 3 local durian accession superior potential ranged from 0.7 to 0.8. In conclusion, the accession of local durian which were Miyem and Rusmiyati have advantage and potential as prospective parent trees.
NASA Astrophysics Data System (ADS)
Ani, Adi Irfan Che; Sairi, Ahmad; Tawil, Norngainy Mohd; Wahab, Siti Rashidah Hanum Abd; Razak, Muhd Zulhanif Abd
2016-08-01
High demand for housing and limited land in town area has increasing the provision of high-rise residential scheme. This type of housing has different owners but share the same land lot and common facilities. Thus, maintenance works of the buildings and common facilities must be well organized. The purpose of this paper is to identify and classify basic facilities for high-rise residential building hoping to improve the management of the scheme. The method adopted is a survey on 100 high-rise residential schemes that ranged from affordable housing to high cost housing by using a snowball sampling. The scope of this research is within Kajang area, which is rapidly developed with high-rise housing. The objective of the survey is to list out all facilities in every sample of the schemes. The result confirmed that pre-determined 11 classifications hold true and can provide the realistic classification for high-rise residential scheme. This paper proposed for redefinition of facilities provided to create a better management system and give a clear definition on the type of high-rise residential based on its facilities.
Mental health and individual experience of unemployed young adults in Japan.
Kito, Aiko; Ueno, Takeji
2016-01-01
This study focused on the subjective experiences and mental health of young, unemployed adults in Japan. We explored how individuals describe their experiences of becoming unemployed and how these experiences influence their mental health within the current Japanese sociocultural context, using a social constructionist approach. We collected data from October 2012 to January 2013. Participants were 25 young unemployed Japanese job seekers (15 females), who were recruited using a purposive sampling strategy including snowball sampling. We conducted semi-structured interviews focusing on participants' previous work and job search experience, their lifestyle and health, the social support they considered necessary, their future job-seeking plans, and their demographic characteristics. Using thematic analysis, we identified four key themes from the interview data: stress relief, re-energization for future work, new job skills acquisition, and lifestyle change. The findings indicate that unemployment is sometimes experienced as more beneficial than employment. This might be because of the poor working environment in Japan, the financial support participants received, and the experience of short-term unemployment. The findings suggest that intervention is necessary to help young adults in Japan find high-quality jobs and that we must promote fair employment and decent working conditions for them.
Lesbian, gay, bisexual, and transgender (LGBT) physicians' experiences in the workplace.
Eliason, Michele J; Dibble, Suzanne L; Robertson, Patricia A
2011-01-01
Little is known about the experiences of lesbian, gay, bisexual, and transgender (LGBT) physicians in the workplace. There is little formal education in medical school about LGBT issues, and some heterosexual physicians have negative attitudes about caring for LGBT patients or working with LGBT coworkers, setting the stage for an exclusive and unwelcoming workplace. The current study used an online survey to assess a convenience sample of 427 LGBT physicians from a database of a national LGBT healthcare organization, as well as a snowball sample generated from the members of the database. Although rates of discriminatory behaviors had decreased since earlier reports, 10% reported that they were denied referrals from heterosexual colleagues, 15% had been harassed by a colleague, 22% had been socially ostracized, 65% had heard derogatory comments about LGBT individuals, 34% had witnessed discriminatory care of an LGBT patient, 36% had witnessed disrespect toward an LGBT patient's partner, and 27% had witnessed discriminatory treatment of an LGBT coworker. Few had received any formal education on LGBT issues in medical school or residency. It appears that medical schools and health care workplaces continue to ignore LGBT issues and operate in discriminatory fashion far too often.
Respondent-driven sampling and the recruitment of people with small injecting networks.
Paquette, Dana; Bryant, Joanne; de Wit, John
2012-05-01
Respondent-driven sampling (RDS) is a form of chain-referral sampling, similar to snowball sampling, which was developed to reach hidden populations such as people who inject drugs (PWID). RDS is said to reach members of a hidden population that may not be accessible through other sampling methods. However, less attention has been paid as to whether there are segments of the population that are more likely to be missed by RDS. This study examined the ability of RDS to capture people with small injecting networks. A study of PWID, using RDS, was conducted in 2009 in Sydney, Australia. The size of participants' injecting networks was examined by recruitment chain and wave. Participants' injecting network characteristics were compared to those of participants from a separate pharmacy-based study. A logistic regression analysis was conducted to examine the characteristics independently associated with having small injecting networks, using the combined RDS and pharmacy-based samples. In comparison with the pharmacy-recruited participants, RDS participants were almost 80% less likely to have small injecting networks, after adjusting for other variables. RDS participants were also more likely to have their injecting networks form a larger proportion of those in their social networks, and to have acquaintances as part of their injecting networks. Compared to those with larger injecting networks, individuals with small injecting networks were equally likely to engage in receptive sharing of injecting equipment, but less likely to have had contact with prevention services. These findings suggest that those with small injecting networks are an important group to recruit, and that RDS is less likely to capture these individuals.
Using Screencasting to Promote Database Trials and Library Resources
ERIC Educational Resources Information Center
Emanuel, Michelle
2013-01-01
At the University of Mississippi, screencasting was used to promote a database trial to the ARTStor Digital Library. Using Jing, a free product used for recording and posting screencasts, and a Snowball USB microphone, 11 videos averaging 3 minutes in length were posted to an online topic guide. Screencasting was used as a quick, creative, and…
Talking Back to Power: Snowballs in Hell and the Imperative of Insisting on Structural Explanations
ERIC Educational Resources Information Center
Francis, Becky; Hey, Valerie
2009-01-01
This viewpoint explores and shares our experience of "doing" feminism in the context of its apparent "demise". We were recently invited to attend an event at the Cabinet Office, to "discuss the impact aspirations and expectations within the community have on the educational achievement of young people in deprived…
ERIC Educational Resources Information Center
Chisholm, James S.; Trent, Brandie
2012-01-01
"Everything...affects everything," from Jay Asher's young adult novel, "Thirteen Reasons Why," captures a central message of this text in which a young woman named Hannah Baker leaves behind a series of tapes addressed to particular individuals who played a part in producing the snowball effect that led to her suicide. "Everything...affects…
Ho, Roger C; Zhang, Melvyn W; Ho, Cyrus S; Pan, Fang; Lu, Yanxia; Sharma, Vijay K
2014-03-19
The widespread forest fires in Indonesia in June 2013 led to widespread haze to neighbouring countries. This is the first study in the medical literature reporting the acute physical and psychological symptoms of the general population during a haze crisis. We evaluated the factors that are associated with psychological stress of haze exposure. This study was conducted between June 21 to June 26, 2013. Participants were recruited by an online recruitment post and snowball sampling techniques. Participants were required to complete an online survey which was composed of demographics questionnaire, physical symptom checklist, perceived dangerous Pollutant Standard Index (PSI) value and views on the N-95 mask and the Impact of Event Scale-Revised (IES-R). A total of 298 participants returned the completed study questionnaire. The respondents reported a mean number of 4.03 physical symptoms (S.D. = 2.6). The five most common physical symptoms include mouth or throat discomfort (68.8%), nose discomfort (64.1%), eye discomfort (60.7%), headache (50.3%) and breathing difficulty (40.3%). The total IES-R score was 18.47 (S.D. = 11.69) which indicated that the study population experienced mild psychological stress but not to the extent of acute stress reaction syndrome. The perceived dangerous PSI level and number of physical symptoms were significantly associated with the mean intrusion score, mean hyper-arousal score, total mean IES-R score and total IES-R score (p < 0.05). Our findings suggest that a haze crisis is associated with acute physical symptoms and mild psychological stress. The number of physical symptoms and the perceived dangerous PSI values are important factors associated with psychological stress.
A qualitative study of the experience of obstetric fistula survivors in Addis Ababa, Ethiopia
Gebresilase, Yenenesh Tadesse
2014-01-01
Research on obstetric fistula has paid limited attention to the lived experiences of survivors. This qualitative study explored the evolution of survivors’ perceptions of their social relationships and health since developing this obstetric complication. In-depth interviews were conducted with eight survivors who were selected based on purposive and snowball sampling techniques. Thematic categorization and content analysis was used to analyze the data. The resultant themes included participants’ understanding of factors predisposing to fistula, challenges they encounter, their coping responses, and the meaning of their experiences. First, the participants had a common understanding of the factors that predisposed them to obstetric fistula. They mentioned poor knowledge about pregnancy, early marriage, cultural practices, and a delay in or lack of access to emergency obstetric care. Second, the participants suffered from powerlessness experienced during their childhood and married lives. They also faced prolonged obstructed labor, physical injury, emotional breakdown, depression, erosion of social capital, and loss of healthy years. Third, to control their negative emotions, participants reported isolating themselves, having suicidal thoughts, positive interpretation about the future, and avoidance. To obtain relief from their disease, the women used their family support, sold their properties, and oriented to reality. Fourth, the participants were struggling to keep going, to accept their changed reality, and to change their perspectives on life. In conclusion, obstetric fistula has significant physical, psychosocial, and emotional consequences. The study participants were not passive victims but rather active survivors of these challenges. Adequate support was not provided by their formal or informal support systems. To prevent and manage obstetric fistula successfully, there should be family-based interventions that improve access to and provision of emergency obstetric care. These initiatives should also ensure men’s participation, women’s empowerment, and the utilization of community-based institutions. PMID:25525395
A qualitative study of emergency physicians’ perspectives on PROMS in the emergency department
Dainty, Katie N; Seaton, Bianca; Laupacis, Andreas; Schull, Michael; Vaillancourt, Samuel
2017-01-01
Introduction There is a growing emphasis on including patients' perspectives on outcomes as a measure of quality care. To date, this has been challenging in the emergency department (ED) setting. To better understand the root of this challenge, we looked to ED physicians' perspectives on their role, relationships and responsibilities to inform future development and implementation of patient-reported outcome measures (PROMs). Methods ED physicians from hospitals across Canada were invited to participate in interviews using a snowballing sampling technique. Semistructured interviews were conducted by phone with questions focused on the role and practice of ED physicians, their relationship with their patients and their thoughts on patient-reported feedback as a mechanism for quality improvement. Transcripts were analysed using a modified constant comparative method and interpretive descriptive framework. Results Interviews were completed with 30 individual physicians. Respondents were diverse in location, training and years in practice. Physicians reported being interested in ‘objective’ postdischarge information including adverse events, readmissions, other physicians’ notes, etc in a select group of complex patients, but saw ‘patient-reported’ feedback as less valuable due to perceived biases. They were unsure about the impact of such feedback mainly because of the episodic nature of their work. Concerns about timing, as well as about their legal and ethical responsibilities to follow-up if poor patient outcomes are reported, were raised. Conclusions Data collection and feedback are key elements of a learning health system. While patient-reported outcomes may have a role in feedback, ED physicians are conflicted about the actionability of such data and ethical implications, given the inherently episodic nature of their work. These findings have important implications for PROM design and implementation in this unique clinical setting. PMID:28183828
Blondal, Anna Bryndis; Jonsson, Jon Steinar; Sporrong, Sofia Kälvemark; Almarsdottir, Anna Birna
2017-08-01
Background For the past several years pharmacists' responsibilities have expanded globally from traditional tasks of dispensing medications to collaborating with other health care professionals in patient care. Similar developments have not occurred in outpatient settings in Iceland. Objective The aim of this study was to explore Icelandic general practitioners' views on the current status of primary care, their perceptions of pharmacists as a health care profession, and their attitudes towards future GP-pharmacist collaboration in primary care in Iceland. Setting Twelve primary care clinics in Iceland. Methods Semi-structured in-depth interviews were conducted with general practitioners from different primary care clinics in Iceland. A purposive and snowball sampling technique was used to select participants. All interviews were recorded and transcribed verbatim. The transcripts were categorized by themes and then analyzed using conventional content analysis. Main outcome measure General practitioners' attitudes towards pharmacists. Results Twenty general practitioners from twelve different primary care clinics in Iceland were interviewed. There are several unmet needs regarding medicines and patient monitoring in the Icelandic health care system. General practitioners suggested ways in which these gaps may be addressed and pharmacist-led clinical service was one of the suggestions. Currently, their communication with pharmacists in the primary sector solely surrounds practical non-clinical issues. Due to increasing polypharmacy and multimorbidity, they suggested that pharmacists should be more involved in patient care. Conclusions General practitioners believe that pharmacist-led clinical service can increase the quality of patient therapy. To improve communication between these health care providers, pharmacists must also re-professionalize (strengthening the profession´s status through new responsibilities and tasks), not having a conflict of interest and showing that they have expertise in patient care.
Medicinal plants used to control internal and external parasites in goats.
Sanhokwe, Marcia; Mupangwa, Johnfisher; Masika, Patrick J; Maphosa, Viola; Muchenje, Voster
2016-04-29
The use of medicinal plants plays a major role in the primary health care of animals in South Africa. A survey was conducted to document medicinal plants used to control parasites in goats in Kwezi and Ntambethemba villages in the Eastern Cape Province, South Africa. Information from 50 farmers and 3 herbalists was obtained through the use of a structured questionnaire, and a snowball sampling technique was used to identify key informants. The obtained data were analysed using PROC FREQ of SAS (2003), and fidelity level values were determined to estimate the healing potential of the mentioned plants. The survey revealed nine plant species belonging to eight families that were used to control parasites in goats. Asphodelaceae (22.22%) was the most frequently used plant family. Leaves were the most used plant parts, constituting 60.38%. They were prepared either as infusions or decoctions of single plants or in mixtures. Aloe ferox, Acokanthera oppositifolia and Elephantorrhiza elephantina were the plants having the highest fidelity level for their use to control parasites, each scoring 100%, followed by Albuca setosa (83.33%). The study revealed low knowledge about ethnoveterinary medicine in the study area. It also revealed that information on ethno-veterinary medicine in this area is mostly confined to older people and there is danger that this knowledge can be lost before being passed on to other generations. Therefore, there is an urgent need to document information on these plant species so that the future generation can benefit. Further investigation should be carried out to validate the efficacy and safety of the above-mentioned plants so as to provide cheap alternative ways of controlling parasites.
Bougangue, Bassoumah; Ling, How Kee
2017-09-06
The need to promote maternal health in Ghana has committed the government to extend maternal healthcare services to the door steps of rural families through the community-based Health Planning and Services. Based on the concerns raised in previous studies that male spouses were indifferent towards maternal healthcare, this study sought the views of men on their involvement in maternal healthcare in their respective communities and at the household levels in the various Community-based Health Planning and Services zones in Awutu-Senya West District in the Central Region of Ghana. A qualitative method was employed. Focus groups and individual interviews were conducted with married men, community health officers, community health volunteers and community leaders. The participants were selected using purposive, quota and snowball sampling techniques. The study used thematic analysis for analysing the data. The study shows varying involvement of men, some were directly involved in feminine gender roles; others used their female relatives and co-wives to perform the women's roles that did not have space for them. They were not necessarily indifferent towards maternal healthcare, rather, they were involved in the spaces provided by the traditional gender division of labour. Amongst other things, the perpetuation and reinforcement of traditional gender norms around pregnancy and childbirth influenced the nature and level of male involvement. Sustenance of male involvement especially, husbands and CHVs is required at the household and community levels for positive maternal outcomes. Ghana Health Service, health professionals and policy makers should take traditional gender role expectations into consideration in the planning and implementation of maternal health promotion programmes.
Exploring the training and scope of practice of GPs in England, Germany and Spain.
Glonti, Ketevan; Struckmann, Verena; Alconada, Alvaro; Pettigrew, Luisa M; Hernandez-Santiago, Virginia; Minue, Sergio; Risso-Gill, Isabelle; McKee, Martin; Legido-Quigley, Helena
2018-03-22
To explore general practitioner (GP) training, continuing professional development, scope of practice, ethical issues and challenges in the working environment in three European countries. Qualitative study of 35 GPs from England, Germany and Spain working in urban primary care practices. Participants were recruited using convenience and snowball sampling techniques. Semi-structured interviews were recorded, transcribed and analysed by four independent researchers adopting a thematic approach. Entrance to and length of GP training differ between the three countries, while continuing professional development is required in all three, although with different characteristics. Key variations in the scope of practice include whether there is a gatekeeping role, whether GPs work in multidisciplinary teams or singlehandedly, the existence of appraisal processes, and the balance between administrative and clinical tasks. However, similar challenges, including the need to adapt to an ageing population, end-of-life care, ethical dilemmas, the impact of austerity measures, limited time for patients and gaps in coordination between primary and secondary care are experienced by GPs in all three countries. Primary health care variations have strong historical roots, derived from the different national experiences and the range of clinical services delivered by GPs. There is a need for an accessible source of information for GPs themselves and those responsible for safety and quality standards of the healthcare workforce. This paper maps out the current situation before Brexit is being implemented in the UK which could see many of the current EU arrangements and legislation to assure professional mobility between the UK and the rest of Europe dismantled. Copyright © 2017. Publicado por Elsevier España, S.L.U.
Siddiqi, Kamran; Scammell, Katy; Huque, Rumana; Khan, Amina; Baral, Sushil; Ali, Shehzad; Watt, Ian
2016-04-01
Most South Asian countries are signatories to the WHO Framework Convention for Tobacco Control (FCTC). However, there is little information on the extent to which FCTC standards are effectively implemented for controlling smokeless tobacco (SLT)-used by over 250 million people in the region. We assessed the feasibility of a novel approach based on interviewing the key actors of SLT supply chain and analyzing its findings using standards set by FCTC. Using a snowball-sampling technique, we interviewed point-of-sale vendors, wholesale retailers, manufacturers, raw-tobacco retailers, and farmers involved in the supply chain of SLT in Bangladesh, Nepal, and Pakistan. Using a structured-questionnaire, participants were asked about their customer profiles; product types; marketing practices; suppliers; profit margins, awareness and adherence to legislation. We recruited 72% (130/180) of all supply chain actors approached. Findings indicate several loopholes in the existing taxation, regulatory, and inspection systems. A significant proportion of smuggled and counterfeit SLT products are available in the market. Most SLT products are sold without recommended warnings, information on their ingredients, and manufacturers' details. There appear to be no restrictions on sale of SLT products to minors. On the other hand, there are also several incentives built-in the supply chain that makes tobacco farming, SLT manufacturing, and its sale a profitable business. Our novel approach to study SLT control was successful in identifying and interviewing actors involved in its supply chain. The analysis using FCTC could provide valuable information to policy makers and enable them to effectively regulate SLT products. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Mazerolle, Stephanie M; Borland, John F; Burton, Laura J
2012-01-01
Female athletic trainers (ATs) experience gender discrimination in the workplace due to stereotypical gender roles, but limited information is available regarding the topic. To understand the challenges and obstacles faced by young female ATs working in National Collegiate Athletic Association Division I athletics. Exploratory study using semistructured interviews. Division I clinical setting. A total of 14 female ATs were included in the study, using both criterion and snowball-sampling techniques. Their mean age was 27 ± 2 years, with 5 ± 2 years of overall clinical experience. Criteria included employment at the Division I clinical setting, being a full-time assistant AT, and at least 3 years of working experience but no more than 9 years to avoid role continuance. Analysis of the interview data followed inductive procedures as outlined by a grounded theory approach. Credibility was established by member checks, multiple-analyst triangulation, and peer review. Clear communication with both coaches and players about expectations and philosophies regarding medical care, a supportive head AT in terms of clinical competence, and having and serving as a role model were cited as critical tools to alleviate gender bias in the workplace. The female ATs in this study stressed the importance of being assertive with coaches early in the season with regard to the AT's role on the team. They reasoned that these actions brought forth a greater perception of congruity between their roles as ATs and their gender and age. We suggest that female athletic training students seek mentors in their field while they complete their coursework and practicums. The ATs in the current study indicated that a mentor, regardless of sex, helped them feel empowered to navigate the male-centric terrain of athletic departments by encouraging them to be assertive and not second-guess their decisions.
Decision to adopt medical technology: case study of breast cancer radiotherapy techniques.
Gold, Heather Taffet; Pitrelli, Kimberly; Hayes, Mary Katherine; Murphy, Madhuvanti Mahadeo
2014-11-01
To understand decision making concerning adoption and nonadoption of accelerated partial breast radiotherapy (RT) prior to long-term randomized trial evidence. A total of 36 radiation oncologists and surgeons were recruited through purposive and snowball sampling strategies from September 2010 through January 2013. Semistructured phone interviews were conducted and audio-recorded and lasted 20-45 minutes. Qualitative analysis was conducted using a framework approach, iteratively exploring key concepts and emerging issues raised by subjects. Interviews were transcribed and imported into Atlas.ti v6. Transcripts were independently coded by 3 researchers shortly after each interview, followed by consensus development on each coded transcript. Barriers and facilitators of adoption, practice patterns, and informational/educational sources concerning accelerated partial breast RT were all assessed to determine major themes. Nearly half of physicians were surgeons (47%), and half were radiation oncologists (53%), with 61% overall in urban settings. Twenty-nine of the 36 physicians interviewed used brachytherapy-based partial breast RT. Five major factors were involved in physicians' decisions to adopt accelerated partial breast RT: facilitators encouraging adoption (e.g., enthusiastic colleagues and patient convenience), financial and prestige incentives, pressures to adopt (e.g., potential declines in referrals), judgment concerning acceptable level of scientific evidence, and barriers (e.g., not having appropriate machinery or referral mechanism in place). If technology was adopted, clinical guideline adherence varied. Technology adoption is based on financial and social pressures, along with often-limited scientific evidence and what seems "best" for patients. For technology adoption and diffusion to be rational and evidence-based, we must encourage appropriate financial payment models to curb use outside of research studies and promote development of additional treatment registries until sufficient evidence is gathered. © The Author(s) 2014.
Gheorghe, Consuela-Mădălina; Gheorghe, Iuliana-Raluca; Purcărea, Victor Lorin
2017-01-01
Nowadays, we live in a world in which we are daily bombed by hundreds of advertisements. Specialists have to discover other channels or embed attractive elements in the advertisements’ messages to cut through the clutter and catch the consumers’ attention. The evolution of the concept of service has changed from the commercial status to determining a lifestyle. Buying a service has led to a change in the consumer behavior. Consumers want to buy services that dazzle their senses, touch their hearts, and stimulate their minds, not as before, excellent or satisfying. Ophthalmology is the medical specialty that is the most oriented toward outpatient care, as hospitalization is required only in a small percentage of cases. The objective of this case study was to investigate the perception of Romanian adult consumers on ophthalmology services from an experiential marketing perspective, by using the Focus Group method. Ophthalmology requires a wide range of skills due to the diversity of consumers who demand specialized consultations. Experiential marketing is a valuable strategy that ophthalmologic organizations may use to target specific consumers. The purpose of this case study was to identify the perceptions of Romanian adults on experiential marketing campaigns and determine the degree to which these campaigns influenced their decisions of buying an ophthalmologic service. Using a snowball sampling technique we have sent a filter questionnaire to 40 people on the internet. The filter questionnaire consisted of questions about wearing eyeglasses, the period of wearing them, the last ophthalmologic consultation, the type of ophthalmologic clinic they were going to, age and education. The respondents revealed there is almost no visibility on promoting services even if there is an upsurge of organizations offering this type of health service in the Romanian ophthalmology sector. PMID:29450395
2014-01-01
Background The widespread forest fires in Indonesia in June 2013 led to widespread haze to neighbouring countries. This is the first study in the medical literature reporting the acute physical and psychological symptoms of the general population during a haze crisis. We evaluated the factors that are associated with psychological stress of haze exposure. Methods This study was conducted between June 21 to June 26, 2013. Participants were recruited by an online recruitment post and snowball sampling techniques. Participants were required to complete an online survey which was composed of demographics questionnaire, physical symptom checklist, perceived dangerous Pollutant Standard Index (PSI) value and views on the N-95 mask and the Impact of Event Scale-Revised (IES-R). Results A total of 298 participants returned the completed study questionnaire. The respondents reported a mean number of 4.03 physical symptoms (S.D. = 2.6). The five most common physical symptoms include mouth or throat discomfort (68.8%), nose discomfort (64.1%), eye discomfort (60.7%), headache (50.3%) and breathing difficulty (40.3%). The total IES-R score was 18.47 (S.D. = 11.69) which indicated that the study population experienced mild psychological stress but not to the extent of acute stress reaction syndrome. The perceived dangerous PSI level and number of physical symptoms were significantly associated with the mean intrusion score, mean hyper-arousal score, total mean IES-R score and total IES-R score (p < 0.05). Conclusions Our findings suggest that a haze crisis is associated with acute physical symptoms and mild psychological stress. The number of physical symptoms and the perceived dangerous PSI values are important factors associated with psychological stress. PMID:24642046
Nyavor, Kunche Delali; Kweku, Margaret; Agbemafle, Isaac; Takramah, Wisdom; Norman, Ishmael; Tarkang, Elvis; Binka, Fred
2017-01-01
Introduction Malaria remains one of the top five killer diseases in sub-Saharan Africa (SSA) and its burden is skewed towards pregnant women and children under five. Insecticide Treated Bed-Net (ITN) usage is considered one of the most cost-effective, preventive interventions against malaria. This study sought to assess ownership, usage, effectiveness, knowledge, access and availability of ITNs among mothers with children under five in the Hohoe municipality. Methods In August 2010 a cross-sectional survey was carried out in 30 communities, selected using the WHO 30 cluster sampling technique. In the selected communities, mothers/caregivers with children under five years were selected using the snowball method. Data were collected through questionnaires and direct observation of ITN. Descriptive statistics was used to analyse the data collected. Results A total of 450 mothers/caregivers were interviewed and their mean age was 30 ± 7 years. ITN ownership was 81.3%, and usage was 66.4%. The majority (97.8%) of the mothers/caregivers said ITNs were effective for malaria prevention. Awareness about ITNs was high (98.7%) and the majority (52.9%) had heard about ITNs from Reproductive and Child Health (RCH) Clinic and antenatal care ANC clinic (33.6%). Over 60% of the ITNs were acquired through free distribution at RCH clinics, clinic and home distribution during mass immunization sessions. The majority of the mothers/caregivers (78.6%) knew the signs and symptoms of malaria, what causes malaria (82.2%) and who is most at risk (90%). Conclusion Behaviour change communication strategies on ITN use may need to be further targeted to ensure full use of available ITNs. PMID:29255537
Ge, Li; Wikby, Kerstin; Rask, Mikael
2017-11-28
To explore the lived experience of women with gestational diabetes mellitus (GDM) living in China in order to add knowledge about how the Chinese women suffer from GDM. A qualitative interpretive interview study. Data were collected with a snowball sampling technique. Phenomenological hermeneutics was used as the analysis method based on Ricoeur's phenomenological hermeneutical interpretation theory. The study was performed at the participants' work places, or at the obstetric clinics or wards at two provincial hospitals and one municipal hospital in the southeast of China. Inclusion criteria were age ≥18 years, diagnosis of GDM without other pregnancy complications, in 34th gestational weeks-postpartum 4th weeks and speaking Mandarin Chinese without speech impediment. 62 women, who met the inclusion criteria, took part in the study. The lived experience of the women with GDM living in China was formulated into a main theme: 'longing for caring care'. The main theme was derived from four themes: being stricken by GDM, wishing to receive caring GDM care, being left alone to struggle with GDM and trying to adjust and adapt to life with GDM. The eagerness for caring care in China was highlighted. The lack of caring care could be one of the possible reasons why the professional-patient relations were deteriorating in China. It could be useful for health providers and health policymakers to receive education and training about caring care. Using the health metaphor of balance and 'patient participation' and 'patient-centred' approaches may benefit women with GDM and thus improve the quality of care in China. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Community Peer-Led Falls Prevention Presentations: What Do the Experts Suggest?
Khong, Linda A M; Berlach, Richard G; Hill, Keith D; Hill, Anne-Marie
2018-04-01
Falls among older adults are a major problem. Despite considerable progress in falls prevention research, older adults often show low motivation to engage in recommended preventive strategies. Peer-led falls prevention education for older adults may have potential for bridging the research evidence-practice gap, thereby promoting the uptake of falls prevention strategies. We evaluated peer educators' presentations of falls prevention education to community-dwelling older adults in regard to established criteria that were consistent with adult learning principles, the framework of health behaviour change, falls prevention guidelines, and recommendations for providing falls prevention information. We conducted a within-stage mixed model study using purposive and snowball sampling techniques to recruit 10 experts to evaluate video recordings of the delivery of three peer-led falls prevention presentations. Each expert viewed three videos and rated them using a questionnaire containing both open-ended and closed items. There was a good level of expert agreement across the questionnaire domains. Though the experts rated some aspects of the presentations highly, they thought that the presentations were mainly didactic in delivery, not consistently personally relevant to the older adult audience, and did not encourage older adults to engage in the preventive strategies that were presented. Based on the experts' findings, we developed five key themes and recommendations for the effective delivery of peer-led falls prevention presentations. These included recommending that peer educators share falls prevention messages in a more interactive and experiential manner and that uptake of strategies should be facilitated by encouraging the older adults to develop a personalised action plan. Findings suggest that if peer-led falls prevention presentations capitalise on older adults' capability, opportunity, and motivation, the older adults may be more receptive to take up falls prevention messages.
Ge, Li; Wikby, Kerstin; Rask, Mikael
2017-01-01
Objective To explore the lived experience of women with gestational diabetes mellitus (GDM) living in China in order to add knowledge about how the Chinese women suffer from GDM. Design A qualitative interpretive interview study. Data were collected with a snowball sampling technique. Phenomenological hermeneutics was used as the analysis method based on Ricoeur’s phenomenological hermeneutical interpretation theory. Setting The study was performed at the participants’ work places, or at the obstetric clinics or wards at two provincial hospitals and one municipal hospital in the southeast of China. Participants Inclusion criteria were age ≥18 years, diagnosis of GDM without other pregnancy complications, in 34th gestational weeks—postpartum 4th weeks and speaking Mandarin Chinese without speech impediment. 62 women, who met the inclusion criteria, took part in the study. Results The lived experience of the women with GDM living in China was formulated into a main theme: ‘longing for caring care’. The main theme was derived from four themes: being stricken by GDM, wishing to receive caring GDM care, being left alone to struggle with GDM and trying to adjust and adapt to life with GDM. Conclusion The eagerness for caring care in China was highlighted. The lack of caring care could be one of the possible reasons why the professional–patient relations were deteriorating in China. It could be useful for health providers and health policymakers to receive education and training about caring care. Using the health metaphor of balance and ‘patient participation’ and ‘patient-centred’ approaches may benefit women with GDM and thus improve the quality of care in China. PMID:29187411
Nyavor, Kunche Delali; Kweku, Margaret; Agbemafle, Isaac; Takramah, Wisdom; Norman, Ishmael; Tarkang, Elvis; Binka, Fred
2017-01-01
Malaria remains one of the top five killer diseases in sub-Saharan Africa (SSA) and its burden is skewed towards pregnant women and children under five. Insecticide Treated Bed-Net (ITN) usage is considered one of the most cost-effective, preventive interventions against malaria. This study sought to assess ownership, usage, effectiveness, knowledge, access and availability of ITNs among mothers with children under five in the Hohoe municipality. In August 2010 a cross-sectional survey was carried out in 30 communities, selected using the WHO 30 cluster sampling technique. In the selected communities, mothers/caregivers with children under five years were selected using the snowball method. Data were collected through questionnaires and direct observation of ITN. Descriptive statistics was used to analyse the data collected. A total of 450 mothers/caregivers were interviewed and their mean age was 30 ± 7 years. ITN ownership was 81.3%, and usage was 66.4%. The majority (97.8%) of the mothers/caregivers said ITNs were effective for malaria prevention. Awareness about ITNs was high (98.7%) and the majority (52.9%) had heard about ITNs from Reproductive and Child Health (RCH) Clinic and antenatal care ANC clinic (33.6%). Over 60% of the ITNs were acquired through free distribution at RCH clinics, clinic and home distribution during mass immunization sessions. The majority of the mothers/caregivers (78.6%) knew the signs and symptoms of malaria, what causes malaria (82.2%) and who is most at risk (90%). Behaviour change communication strategies on ITN use may need to be further targeted to ensure full use of available ITNs.
Fishers' knowledge about fish trophic interactions in the southeastern Brazilian coast.
Ramires, Milena; Clauzet, Mariana; Barrella, Walter; Rotundo, Matheus M; Silvano, Renato Am; Begossi, Alpina
2015-03-05
Data derived from studies of fishers' local ecological knowledge (LEK) can be invaluable to the proposal of new studies and more appropriate management strategies. This study analyzed the fisher's LEK about trophic relationships of fishes in the southeastern Brazilian coast, comparing fishers' LEK with scientific knowledge to provide new hypotheses. The initial contacts with fishers were made through informal visits in their residences, to explain the research goals, meet fishers and their families, check the number of resident fishers and ask for fishers' consent to participate in the research. After this initial contact, fishers were selected to be included in the interviews through the technique of snowball sampling. The fishers indicated by others who attended the criteria to be included in the research were interviewed by using a semi-structured standard questionnaire. There were interviewed 26 artisanal fishers from three communities of the Ilhabela: Jabaquara, Fome and Serraria. The interviewed fishers showed a detailed knowledge about the trophic interactions of the studied coastal fishes, as fishers mentioned 17 food items for these fishes and six fish and three mammals as fish predators. The most mentioned food items were small fish, shrimps and crabs, while the most mentioned predators were large reef fishes. Fishers also mentioned some predators, such as sea otters, that have not been reported by the biological literature and are poorly known. The LEK of the studied fishers showed a high degree of concordance with the scientific literature regarding fish diet. This study evidenced the value of fishers' LEK to improve fisheries research and management, as well as the needy to increase the collaboration among managers, biologists and fishers.
Gheorghe, Consuela-Mădălina; Gheorghe, Iuliana-Raluca; Purcărea, Victor Lorin
2017-01-01
Nowadays, we live in a world in which we are daily bombed by hundreds of advertisements. Specialists have to discover other channels or embed attractive elements in the advertisements' messages to cut through the clutter and catch the consumers' attention. The evolution of the concept of service has changed from the commercial status to determining a lifestyle. Buying a service has led to a change in the consumer behavior. Consumers want to buy services that dazzle their senses, touch their hearts, and stimulate their minds, not as before, excellent or satisfying. Ophthalmology is the medical specialty that is the most oriented toward outpatient care, as hospitalization is required only in a small percentage of cases. The objective of this case study was to investigate the perception of Romanian adult consumers on ophthalmology services from an experiential marketing perspective, by using the Focus Group method. Ophthalmology requires a wide range of skills due to the diversity of consumers who demand specialized consultations. Experiential marketing is a valuable strategy that ophthalmologic organizations may use to target specific consumers. The purpose of this case study was to identify the perceptions of Romanian adults on experiential marketing campaigns and determine the degree to which these campaigns influenced their decisions of buying an ophthalmologic service. Using a snowball sampling technique we have sent a filter questionnaire to 40 people on the internet. The filter questionnaire consisted of questions about wearing eyeglasses, the period of wearing them, the last ophthalmologic consultation, the type of ophthalmologic clinic they were going to, age and education. The respondents revealed there is almost no visibility on promoting services even if there is an upsurge of organizations offering this type of health service in the Romanian ophthalmology sector.
Mohammadnezhad, Masoud; Tsourtos, George; Wilson, Carlene; Ratcliffe, Julie; Ward, Paul
2015-01-01
Smokers of all ages can benefit by quitting, but many smokers continue to smoke. Older Greek-Australian smokers, one of the largest ethnic groups in Australia, have higher rates of smoking than other groups of older Australians. This qualitative study aimed to explore older Greek-Australians’ views about socio-cultural influences on their smoking. A snowball sampling technique was used to identify twenty Greek–Australian smokers (12 males and eight females), aged ≥ 50 years. They were recruited through the Greek Orthodox Community Center of South Australia (GOCSA). Qualitative data were collected using semi-structured face-to-face interviews. The audio-taped interviews were translated and transcribed, and then analysed using content analysis. Results suggested that smoking was considered as the “norm” by older Greek-Australian smokers. There were four groups embedded in the participants’ social networks that were reported to be important in relation to either encouraging smoking or, smoking abstinence. These support groups included: family members, friends, the Greek community, and physicians. Smokers’ family members (brothers) and friends were identified as facilitators of smoking whereas non-smoker family members (children and spouses) were reported as providing barriers to smoking. Different approaches were used by supporter groups to assist smokers to quit smoking—both planned and unplanned. Knowledge, planning of social and cultural supports, and addressing barriers to smoking cessation are a important part of health planning for older Greek-Australians. Social norms, including those arising from social interactions, and predisposing traits can influence smoking behaviour. Addressing the specific barriers to smoking cessation of older Greek-Australians is critical to addressing the risk for chronic disease in this group. PMID:25739006
Mohammadnezhad, Masoud; Tsourtos, George; Wilson, Carlene; Ratcliffe, Julie; Ward, Paul
2015-03-02
Smokers of all ages can benefit by quitting, but many smokers continue to smoke. Older Greek-Australian smokers, one of the largest ethnic groups in Australia, have higher rates of smoking than other groups of older Australians. This qualitative study aimed to explore older Greek-Australians' views about socio-cultural influences on their smoking. A snowball sampling technique was used to identify twenty Greek-Australian smokers (12 males and eight females), aged ≥50 years. They were recruited through the Greek Orthodox Community Center of South Australia (GOCSA). Qualitative data were collected using semi-structured face-to-face interviews. The audio-taped interviews were translated and transcribed, and then analysed using content analysis. Results suggested that smoking was considered as the "norm" by older Greek-Australian smokers. There were four groups embedded in the participants' social networks that were reported to be important in relation to either encouraging smoking or, smoking abstinence. These support groups included: family members, friends, the Greek community, and physicians. Smokers' family members (brothers) and friends were identified as facilitators of smoking whereas non-smoker family members (children and spouses) were reported as providing barriers to smoking. Different approaches were used by supporter groups to assist smokers to quit smoking-both planned and unplanned. Knowledge, planning of social and cultural supports, and addressing barriers to smoking cessation are a important part of health planning for older Greek-Australians. Social norms, including those arising from social interactions, and predisposing traits can influence smoking behaviour. Addressing the specific barriers to smoking cessation of older Greek-Australians is critical to addressing the risk for chronic disease in this group.
Teenagers' Awareness of Peers' Substance and Drug Use in Kuwait.
Omu, Florence E; Bader, Al-Wadaany; Helen, Delles; Slabeeb, Shukriya; Safar, Hanan; Omu, Alexander E
Teenage substance use is a global challenge, and youths residing in Kuwait are not immune from it. Tobacco products are licit; however, alcohol and other mood-altering illicit substance are prohibited with severe penalties including imprisonment. Youths residing in Kuwait are being initiated into the use of mood-altering substances like tobacco at an early age, and it is postulated that, as they grow older, they may progress into using alcohol and other prohibited illicit drugs. The aim of this study was to determine licit and illicit substance use by teenagers residing in Kuwait. The study will also explore their awareness of substance use among their peers. A cross-sectional survey using a snowball sampling technique was used to recruit 190 teenagers aged 15-18 years residing in Kuwait. Data were collected using the 130-item questionnaire adapted from 1998 New Jersey Triennial Public High School Survey of Drug and Alcohol Use. Data collection was from September 2012 to June 2013. The Statistical Package for Social Sciences Version 22 for Windows was used. Pearson's chi-square, Kruskal-Wallis, and Mann-Whitney U tests were used to test the hypotheses. Tobacco was the most commonly used substance by these teenagers; 8.4% were current smokers, and 50% had experimented. Age of initiation for 21% was before 14 years old. Hashish (marijuana) was the most commonly used illicit drug, with 3.7% current users and 5.3% claiming to have used it. More male than female teenagers in Grade 9 were using tobacco products (χ = 27.428, df = 5, p < .001). The use and abuse of mood/mind-altering licit and illicit substances appear to be increasing among older teenagers. Intensifying campaigns about the hazards of substance use and drug testing should start from the primary school level.
NASA Astrophysics Data System (ADS)
Ashley, K. T.; Webb, L. E.; Spear, F. S.; Thomas, J. B.
2010-12-01
Geochemical, microstructural and petrological analyses were conducted on metapelites from the Strafford Dome, Vermont. Samples record metamorphic conditions from biotite to peak kyanite/staurolite grade and preserve microstructures related to two nappe emplacement events. The Ti-in-quartz (“TitaniQ”) thermobarometer was used on quartz in different microstructural settings throughout the Strafford Dome, where the petrologic and structural framework is well established, to examine the ability to more precisely constrain pressure-temperature-time-deformation (P-T-t-D) histories. Cathodoluminescence (CL) imaging of quartz was conducted to qualitatively assess the distribution of Ti in a single crystal and/or compare neighboring crystals. In addition to [Ti], strain in the crystal lattice also appears to influence CL intensity. Quartz inclusions in garnet porphyroblasts typically have brighter rims (typically <5 μm) when observed in CL and is attributed to diffusion of Ti from the garnet. X-ray mapping of a snowball garnet (staurolite/kyanite zone) reveals, from core to rim, increasing X_{prp}, decreasing X_{sps}, and constant X_{alm}; Ca increase is limited to near the rim. This spatial variation in chemistry suggests garnet growth during increasing pressure and slightly decreasing temperature most likely associated with nappe emplacement. Most quartz inclusions contain bright bands in CL correlating to planar defects. Preliminary analysis shows [Ti] in quartz near the core of the snowball garnet to be 10.5-13.0 ppm, ≥12.5 ppm near the garnet rim, 8.0-11.0 ppm in the matrix grains, and 17.0 ppm near foam texture triple junctions. Rotated garnets locally contain inclusions that appear brecciated in CL images (kyanite/staurolite zone). In samples where the dominant foliation is a bedding parallel schistosity (S_{1}), ribbon quartz grains and subgrains are present (kyanite/staurolite zone). The subgrains typically have sharp, dark rims with brighter mantles. Some grains contain dark cores near the center. Larger ribbon grains still have the dark rims, but are more homogeneous internally. Crenulated matrix quartz (S_{2}), where present, contains bright rims with darker mantles (garnet zone). In some cases, bright cores are found in the center of these grains. Quartz veins that post-date the foliation within the samples are typically homogeneous, with only minor patchy bright spots present and no observable zoning. Deformed quartz veins in some samples contain ribbon quartz and preserve subgrain rotation recrystallization microstructures (kyanite/staurolite zone). The ribbon quartz is very patchy where subgrains are beginning to consume the ribbon grain. Data from secondary ion mass spectrometry will be presented for spot analyses of [Ti] from locations selected based on microstructural and CL textural significance, and P-T-t-D histories evaluated in the context of previous studies. These findings will further elucidate the potential of TitaniQ for use in studies of metamorphic tectonites, continental tectonics and rheology.
2012-01-01
Background Blue Land Crab (Cardisoma guanhumi) is one of the most important crustacean species captured and commercialized in Brazil. Although this species is not considered to be threatened with extinction, populations of C. guanhumi are known to be rapidly diminishing due to heavy harvesting pressures and degradation of their natural habitats, highlighting the necessity of developing and implanting management and protection strategies for their populations. There have been no ethnozoological publications that have focused specifically on C. guanhumi, in spite of importance of this type of information for developing efficient management plans of resource utilization. So, the present work describes the ethnoecological aspects of the capture and commercialization of C. guanhumi by a fishing community in northeastern Brazil. Methods Field work was carried out in the municipality of Mucuri, Bahia in Brazil, between the months of January and March/2011 through the use of open semi-structured interviews with all of the crustacean harvesters in city who acknowledged their work in capturing this species, totaling 12 interviewees. The informants were identified through the use of the "snowball" sampling technique. In addition to the interviews themselves, the "guided tour" technique and direct observations was employed. Results According all the interviewees, the C. guanhumi is popularly called "guaiamum" and is collected in "apicum" zones. They recognize sexual dimorphism in the species based on three morphological characteristics and the harvesters also pointed two stages in the reproductive cycle during the year and another phase mentioned by the interviewees was ecdysis. All of the interviewed affirmed that the size and the quantities C. guanhumi stocks in Mucuri have been diminishing. All of the interviewees agreed that the species and other mangrove resources constituted their principal source of income. The harvesters dedicated three to five days a week to collect Blue Land Crabs and the principal technique utilized for capturing is a trap called a "ratoeira" (rat-trap). Conclusions The results of the present work demonstrated that the community retains a vast and important volume of knowledge about C. guanhumi that could subsidize both scientific studies and the elaboration of viable management and conservation strategies for this species. PMID:22429762
Witteman, Holly O; Bouck, Zachary; Bravo, Caroline A; Desveaux, Laura; Llovet, Diego; Presseau, Justin; Saragosa, Marianne; Taljaard, Monica; Umar, Shama; Grimshaw, Jeremy M; Tinmouth, Jill; Ivers, Noah M
2018-01-01
Background Cancer Care Ontario’s Screening Activity Report (SAR) is an online audit and feedback tool designed to help primary care physicians in Ontario, Canada, identify patients who are overdue for cancer screening or have abnormal results requiring follow-up. Use of the SAR is associated with increased screening rates. To encourage SAR use, Cancer Care Ontario sends monthly emails to registered primary care physicians announcing that updated data are available. However, analytics reveal that 50% of email recipients do not open the email and less than 7% click the embedded link to log in to their report. Objective The goal of the study is to determine whether rewritten emails result in increased log-ins. This manuscript describes how different user- and theory-informed messages intended to improve the impact of the monthly emails will be experimentally tested and how a process evaluation will explore why and how any effects observed were (or were not) achieved. Methods A user-centered approach was used to rewrite the content of the monthly email, including messages operationalizing 3 behavior change techniques: anticipated regret, material incentive (behavior), and problem solving. A pragmatic, 2x2x2 factorial experiment within a multiphase optimization strategy will test the redesigned emails with an embedded qualitative process evaluation to understand how and why the emails may or may not have worked. Trial outcomes will be ascertained using routinely collected administrative data. Physicians will be recruited for semistructured interviews using convenience and snowball sampling. Results As of April 2017, 5576 primary care physicians across the province of Ontario, Canada, had voluntarily registered for the SAR, and in so doing, signed up to receive the monthly email updates. From May to August 2017 participants received the redesigned monthly emails with content specific to their allocated experimental condition prompting use of the SAR. We have not yet begun analyses. Conclusions This study will inform how to communicate effectively with primary care providers by email and identify which behavior change techniques tested are most effective at encouraging engagement with an audit and feedback report. Trial Registration ClinicalTrials.gov NCT03124316; https://clinicaltrials.gov/ct2/show/NCT03124316 (Archived by WebCite at http://www.webcitation.org/6w2MqDWGu) PMID:29453190
A menu with prices: Annual per person costs of programs addressing community integration.
Leff, H Stephen; Cichocki, Ben; Chow, Clifton; Salzer, Mark; Wieman, Dow
2016-02-01
Information on costs of programs addressing community integration for persons with serious mental illness in the United States, essential for program planning and evaluation, is largely lacking. To address this knowledge gap, community integration programs identified through directories and snowball sampling were sent an online survey addressing program costs and organizational attributes. 64 Responses were received for which annual per person costs (APPC) could be computed. Programs were categorized by type of services provided. Program types differed in median APPCs, though median APPCs identified were consistent with the ranges identified in the limited literature available. Multiple regression was used to identify organizational variables underlying APPCs such as psychosocial rehabilitation program type, provision of EBPs, number of volunteers, and percentage of budget spent on direct care staff, though effects sizes were moderate at best. This study adds tentative prices to the menu of community integration programs, and the implications of these findings for choosing, designing and evaluating programs addressing community integration are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.
Vodouhe, Fifanou G; Khasa, Damase P
2015-01-01
This work explores factors supporting people perception about mine site restoration and phytoremediation. Phytoremediation is one of the most eco-friendly restoration strategy emerged since the last two decades but studies on local people perception on this restoration strategy are scarce. To fill in this gap, data were collected from mining stakeholders using a structured questionnaire administered through snowball sampling method. We used Multiple Correspondence Analysis as implemented in the software XLSTAT to visualize relationship between participants' characteristics, their view on mine site restoration and phytoremediation. Results clearly show out that people perception on mine site restoration is influenced by mining activities effects on health and region attractiveness. Phytoremediation (65.21%) was rated positively with regard to its environment potential, aesthetic and consideration for future generation followed by fillings and excavating. Restoration strategy costs have no effect on people choice and participants prefer use of shrubs as vegetation component of phytoremediation to reach their restoration objective.
Female genital cosmetic surgery: Investigating the role of the general practitioner.
Harding, Tristan; Hayes, Jenny; Simonis, Magdalena; Temple-Smith, Meredith
2015-01-01
Labiaplasty, the surgical reduction of the labia minora, has significantly increased in demand in Australia. Although general practice is one gatekeeper for patients requesting labiaplasty, as a referral is necessary to claim Medicare entitlements, there is little information available to assist general practitioners (GPs) in managing these requests for female genital cosmetic surgery. Semi-structured interviews were conducted with health professionals, including GPs, gynaecologists and plastic surgeons. Participants were recruited through the Victorian Primary Care Practice-based Research Network (VicReN), clinical teaching hospitals and snowball sampling. All interviews were digitally recorded, transcribed, and analysed using content and thematic analysis. Twenty-seven interviews were conducted. All participants were aware of genital labiaplasty; many had patients who were concerned about genital appearance, for which information had often been sought opportunistically. All participants agreed on the need for resources to inform women of normal genital appearance. This novel study demonstrates a need for clinical resources for GPs managing requests for genital labiaplasty.
Risk of HIV infection among men having sex with men in Kathmandu Valley, Nepal.
Deuba, Keshab; Karki, Deepak Kumar; Shrestha, Rachana; Aryal, Umesh Raj; Bhatta, Laxmi; Rai, Krishna Kumar
2014-03-01
Despite extensive distribution of free condoms and lubricants to prevent HIV transmission among men having sex with men (MSM) in Nepal, the prevalence of HIV and risky sexual behaviors remain high. The influence of individual-level, social-capital, and social-structural factors on HIV risk has been insufficiently explored in MSM. The authors assessed association of these factors with HIV risk among 150 MSM enrolled using snowball sampling in the Kathmandu Valley. HIV risk was calculated on the basis of number and type of sexual partners and condom use during anal sex. Multivariate analysis showed a high risk of HIV infection was significantly associated with being involved in sex work, having no knowledge of male sexually transmitted infection (STI) symptoms, and having a history of STI symptoms. HIV prevention could be made more effective by targeting MSM who are involved in sex work and by improving their knowledge of male STI symptoms and early diagnosis and treatment.
Correlates of HIV Testing Among Transgender Women in Ho Chi Minh, Vietnam.
Bao, An; Colby, Donn J; Trang, Toan; Le, Bao Quoc; Dinh, Thien Duc; Nguyen, Quan Hoang; Hoang, Huyen Thi; Friedman, M Reuel; Stall, Ron
2016-12-01
HIV prevalence among transgender women (TW) in Ho Chi Minh City is estimated at 18 %. However, no evidence-based programs or surveillance data exist in Vietnam specific to HIV testing uptake. We examined prevalence and correlates of past-year HIV testing among TW (n = 204) recruited in 2015 via snowball sampling. 59.3 % reported HIV testing in the previous year. In adjusted models, factors positively associated with HIV testing included consistent condom use during sex work with male clients; STI testing in past year; sex with casual partners in the past month; and experiences of police harassment. Factors negatively associated with recent HIV testing included daily/weekly alcohol use and post-traumatic stress symptoms. This study found significant associations between greater safety in sexual behaviors and higher rates of HIV testing. Targeted and specific services are needed for TW in Vietnam in order to address sexual risk behaviors and provide appropriate access to regular HIV testing.
Sexting: young women's and men's views on its nature and origins.
Walker, Shelley; Sanci, Lena; Temple-Smith, Meredith
2013-06-01
This study addresses a gap in evidence regarding the nature and origins of the phenomenon of sexting from the perspective of young people. A qualitative methodology was used, involving individual semistructured interviews with 33 young people aged 15-20 years. Participants were sourced via youth health, recreational, and educational settings using purposive snowball sampling. Results were organized using NVivo, and themes were generated. Interviews with 15 males and 18 females exposed a number of themes, including the gendered nature of sexting, which is the focus of this article. Of particular concern is the theme of pressure experienced by both young women and young men to be involved in the behavior. Findings highlight important implications for the design of strategies to prevent the potential harmful consequences of sexting. For prevention approaches to be effective, they must consider the underlying origins of the behavior and the online sociocultural context within which young people live. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Executive function deficits in short-term abstinent cannabis users.
McHale, Sue; Hunt, Nigel
2008-07-01
Few cognitive tasks are adequately sensitive to show the small decrements in performance in abstinent chronic cannabis users. In this series of three experiments we set out to demonstrate a variety of tasks that are sufficiently sensitive to show differences in visual memory, verbal memory, everyday memory and executive function between controls and cannabis users. A series of three studies explored cognitive function deficits in cannabis users (phonemic verbal fluency, visual recognition and immediate and delayed recall, and prospective memory) in short-term abstinent cannabis users. Participants were selected using snowball sampling, with cannabis users being compared to a standard control group and a tobacco-use control group. The cannabis users, compared to both control groups, had deficits on verbal fluency, visual recognition, delayed visual recall, and short- and long-interval prospective memory. There were no differences for immediate visual recall. These findings suggest that cannabis use leads to impaired executive function. Further research needs to explore the longer term impact of cannabis use. Copyright 2008 John Wiley & Sons, Ltd.
Social Work's Role in Medicaid Reform: A Qualitative Study.
Bachman, Sara S; Wachman, Madeline; Manning, Leticia; Cohen, Alexander M; Seifert, Robert W; Jones, David K; Fitzgerald, Therese; Nuzum, Rachel; Riley, Patricia
2017-12-01
To critically analyze social work's role in Medicaid reform. We conducted semistructured interviews with 46 stakeholders from 10 US states that use a range of Medicaid reform approaches. We identified participants using snowball and purposive sampling. We gathered data in 2016 and analyzed them using qualitative methods. Multiple themes emerged: (1) social work participates in Medicaid reform through clinical practice, including care coordination and case management; (2) there is a gap between social work's practice-level and systems-level involvement in Medicaid innovations; (3) factors hindering social work's involvement in systems-level practice include lack of visibility, insufficient clarity on social work's role and impact, and too few resources within professional organizations; and (4) social workers need more training in health transformation payment models and policy. Social workers have unique skills that are valuable to building health systems that promote population health and reduce health inequities. Although there is considerable opportunity for social work to increase its role in Medicaid reform, there is little social work involvement at the systems level.
The rise and fall of complementary medicine in National Health Service hospitals in England.
Cant, Sarah; Watts, Peter; Ruston, Annmarie
2012-08-01
Whilst Complementary and Alternative Medicine (CAM) has never been systematically integrated into National Health Service (NHS) provision, there has been some limited evidence of a developing presence of CAM in NHS hospital based nursing and midwifery. This paper reports on a qualitative study that sought to document the nature and extent of such integrative practice in England, and the interpersonal and organisational factors that facilitated or impeded it. The data revealed a history in which attempts to integrate CAM had some initial success underpinned by the enthusiasm of individual practitioners and a relatively permissive organisational context. However, this was followed by a decline in service provision. The fact that the services were established by individuals left them vulnerable when more restrictive funding and governance regimes emerged. Whilst the data revealed a consistent story about CAM within the NHS, it must be recognised that the use of a snowball sample limits the generalizability of the findings. Copyright © 2012 Elsevier Ltd. All rights reserved.
Muturi, Nancy
2016-01-01
The current study explores community perspectives on alcohol abuse prevention strategies in rural Kenya. Data from focus group discussions with members of community organizations and in-depth interviews with a snowball sample of key informants revealed that rural communities view national alcohol abuse prevention interventions as ineffective and messages as unpersuasive in changing this high-risk behavior. The use of ethnic languages, stronger fear appeals, and visual aids were recommended for alcohol prevention messages aimed at communities with low literacy. Community members favored narratives and entertainment-education strategies, which are more engaging, and print media for their educational value. Health activism, although common, was viewed as less effective in motivating individuals to change drinking behavior but more effective in advocacy campaigns to pressure the government to enforce alcohol regulations. This study suggests further empirical research to inform evidence-based prevention campaigns and to understand how to communicate about alcohol-related health risks within communities that embrace alcohol consumption as a cultural norm.
WFC3: IR Detector On-Orbit Performance
NASA Astrophysics Data System (ADS)
Hilbert, Bryan; Dulude, M.; McCullough, P.; MacKenty, J. W.; Kimble, R. A.; Hill, R. J.; Viana, A.; Bushouse, H.; Baggett, S.; WFC3 Team
2010-01-01
Using data taken during Servicing Mission Observatory Verification (SMOV4), we have characterized dark current and readnoise behavior of the IR Channel, along with its level of measured background signal. Using data taken in June and July of 2009, we find the dark current in the IR channel to be 0.043 - 0.050 e-/s/pixel. The correlated double sampling (CDS) read noise in RAPID sequences is 20-22 electrons, similar to that measured in ground testing. The effective noise measured in an image created from 16 reads of a SPARS200 ramp is 11.6 - 12.7 electrons. Using internal flat field images, we measured the inverse gain to be 2.28 - 2.47 ± 0.04 e-/ADU, depending on quadrant. The ratio of the mean instrumental irradiance (ADU/s/pixel) measured on orbit to that obtained in ground testing is 1.06 - 1.07, indicating a brightening of the Tungsten lamp on orbit. We also note the continued appearance of cosmic ray-like sources, dubbed "snowballs", in on orbit data.
Ingredients for Success: Strategies to Support Local Food Use in Health Care Institutions.
Linton, Emily; Keller, Heather; Duizer, Lisa
2018-06-12
There is growing interest in use of local food within health care institutions such as hospitals and long-term care homes. This study explored stakeholder perspectives on (i) influences on local food use and (ii) strategies that support success and sustainability of use in health care institutions. Fifteen participants who were institutional leaders with experience in implementing or supporting local food use in health care institutions in Ontario were recruited through purposeful and snowball sampling. A semi-structured interview was conducted by telephone and audio-recorded. Qualitative content analysis identified that influences on local food use were: product availability, staff and management engagement, and legislation and resources (e.g., funding, labour). Several strategies were offered for building and sustaining success including: setting goals, requesting local food availability from suppliers, and more clearly identifying local foods in product lists. The influences and potential strategies highlighted in this paper provide a greater understanding for dietitians and food service managers on how local foods can be incorporated into health care institutions.
Ethical problems experienced by oncology nurses.
da Luz, Kely Regina; Vargas, Mara Ambrosina de Oliveira; Schmidtt, Pablo Henrique; Barlem, Edison Luiz Devos; Tomaschewski-Barlem, Jamila Geri; da Rosa, Luciana Martins
2015-01-01
To know the ethical problems experienced by oncology nurses. Descriptive and exploratory study with a qualitative approach, performed in inpatient units and in chemotherapy out-patients units that provide assistance to oncological patients in two capitals in the South region of Brazil. Eighteen nurses participated in this study, selected by snowball sampling type. For data collection, semi-structured interviews were carried out, which were recorded and transcribed, and then analyzed by thematic analysis. Two categories were established: when informing or not becomes a dilemma - showing the main difficulties related to oncological treatment information regarding health staff, health system, and infrastructure; to invest or not - dilemmas related to finitude - showing situations of dilemmas related to pain and confrontation with finitude. For the effective confrontation of the ethical problems experienced by oncology nurses to occur, it is important to invest in the training of these professionals, preparing them in an ethical and human way to act as lawyers of the patient with cancer, in a context of dilemmas related mainly to the possibility of finitude.
The lived experience of part-time baccalaureate nursing faculty.
Gazza, Elizabeth A; Shellenbarger, Teresa
2010-01-01
Hiring part-time nursing faculty may impact students, faculty careers, and the institution. Yet, little has been studied, particularly in nursing, regarding the experiences of these faculty. This hermeneutic phenomenological study seeks to understand the lived experience of being a part-time faculty member in a baccalaureate nursing program. Through purposive and snowball sampling, nine nursing faculty in part-time positions in northeastern baccalaureate nursing programs participated in in-depth personal interviews. Four themes were uncovered during data analysis, including achieving the dream, a group divided, for the love of the students, and jump in and figure it out. Results of the study seem to indicate that the experience of being a part-time faculty differs in several ways from being a full-time faculty. Understanding part-time faculty experiences provides insight into faculty needs, issues, and concerns while facilitating the development of research-based recruitment and retention strategies. Recommendations for those involved in nursing education, including nursing faculty and administrators, are provided. Copyright © 2010 Elsevier Inc. All rights reserved.
Substance abuse among migrant workers of Thai-Laos border, Thailand.
Jaichuang, Siriluk; Ratanasiri, Amornrat; Kanato, Manop
2012-09-01
Study the impact of substance abuse among migrant workers along the Thai-Laos border region in Nakhon Phanom Province. The target population included migrant workers aged 15 years and over and were selected using the snowball technique. Data were collected from 300 migrant workers and in-depth interviews and focus group discussion were carried out. Data analysis used content analysis, descriptive statistics, and multivariate logistic regression. Fifty-five point seven percent of migrant workers used stimulants namely tobacco, energy drinks, coffee, and methamphetamine. Males were at greater risk for substance abuse than females (AOR 16.03; 95% CI 8.43-30.45) and those who received news and information from community radios and news broadcasting towers were at more risk than other media (AOR 5.38; 95% CI 2.88-10.05). The impact of substance abuse were found to be chronic cough, moodiness, lack of interest in food, headache, wakefulness, sleeplessness, tremor heart palpitation, and accidents. Health promotion strategy must be implemented to minimize the harm. Motivating behavioral modification while keeping in mind the lifestyle, work, and environment of these people could help.
A Sulfate Aerosol Trigger for the Sturtian Neoproterozoic Snowball Event
NASA Astrophysics Data System (ADS)
Wordsworth, R. D.; Macdonald, F. A.
2017-12-01
Despite the dominance of the carbon cycle in determining the evolution of Earth's climate in general, certain events defy easy explanation via atmospheric CO2 changes alone. Here we discuss the particular role that transient planetary albedo changes via sulfate aerosol formation can play in major climate transitions. Specifically, we propose that SO2 outgassing associated with the eruption of the Franklin Large Igneous Province (LIP) led to the first Neoproterozoic Snowball event, the Sturtian, 716 Ma. We summarize U/Pb zircon and baddeleyite dating indicating the synchronicity of the Franklin eruptions and the onset of the Sturtian, and paleomagnetic data indicating that the Franklin erupted close to the equator. We then discuss in detail the modeling we have performed of eruption rate, the plume height achieved during basaltic fissure volcanism, the chemistry and microphysics of sulfate aerosol formation, and the dependence of aerosol longwave and shortwave radiative effects on atmospheric loading, particle size and surface albedo. We discuss the critical importance of the latitude of eruption, the tropopause height, and ocean dynamics in determining the strength and sign of aerosol radiative forcing. We finish by comparing the Franklin event with other LIP emplacement events in Earth history and make suggestions for future modeling.
[Program of studies on psychiatric epidemiology in Argentina. General report].
Casullo, M M
1980-12-01
This paper is an outline of a wide program that is currently under development in the large territory of Argentina. The Director of the Program is Dr. Fernando Pagés Larraya; it is supported by the National Council of Scientific Researches (CONICET) and the National Board of Mental Health. The general purpose of the program is to study the prevalence of mental disorders in different ethnographic areas within the country. Epidemiology allows the forecasting of disease occurence. A research work this area may be qualified "effective" if it provides useful data for prevention programs. Therefore, it is necessary that researches and professional responsibles of Mental Health Governmental decissions work together. This rapprochment is being attempted in developing the Argentine research program. It has a cross-cultural approach. It can be called "a way of thinking" as opposed to a precise methodology. A considerable variety of research tools are being used, depending on the specific purposes and the characteristics of the ethnographic areas. One of the main difficulties in choosing a technique for "case-finding" is uncertainty about where to place the "cut-off point" between presence and absence of illness. In this program the Present State Examination (PSE) is used in population surveys of large urban centers. It is a semi-structured interview that has been extensively tested. In small rural communities, the work is done using "key-informants" and applying the snow-ball sample technique. One specific purpose of the research is the study of the modal personality structure in each ethnographic area, formulated in terms of the Holtzman Inkblot Test. The paper shows the relationships between purposes, research tools and responsible professionals. There is hardly time or surplus intellectual energy for polemic and alienation between clinicians and social scientists. Theories, methodologies, research data and prevention programs have not developed harmoniously. We need to carry out research work not divorced from Public Health responsible authorities, in order to avoid that useful data from Epidemiological Studies will not be used in prevention programs.
Loignon, Christine; Haggerty, Jeannie L; Fortin, Martin; Bedos, Christophe P; Allen, Dawn; Barbeau, David
2010-03-25
The quality of the physician-patient therapeutic relationship is a key factor in the effectiveness of care. Unfortunately, physicians and people living in poverty inhabit very different social milieux, and this great social distance hinders the development of a therapeutic alliance. Social competence is a process based on knowledge, skills and attitudes that support effective interaction between the physician and patient despite the intervening social distance. It enables physicians to better understand their patients' living conditions and to adapt care to patients' needs and abilities. This qualitative research is based on a comprehensive design using in-depth semi-structured interviews with 25 general practitioners working with low-income patients in Montreal's metropolitan area (Québec, Canada). Physicians will be recruited based on two criteria: they provide care to low-income patients with at least one chronic illness, and are identified by their peers as having expertise in providing care to a poor population. For this recruitment, we will draw upon contacts we have made in another research study (Loignon et al., 2009) involving clinics located in poor neighbourhoods. That study will include in-clinic observations and interviews with physicians, both of which will help us identify physicians who have developed skills for treating low-income patients. We will also use the snowball sampling technique, asking participants to refer us to other physicians who meet our inclusion criteria. The semi-structured interviews, of 60 to 90 minutes each, will be recorded and transcribed. Our techniques for ensuring internal validity will include data analysis of transcribed interviews, indexation and reduction of data with software qualitative analysis, and development and validation of interpretations. This research project will allow us to identify the dimensions of the social competence process that helps physicians establish therapeutic relationships with low-income patients living with chronic illness. This study will also offer concrete recommendations for improving health interventions among low-income patients and for helping them to better manage their chronic illnesses. Ultimately, our aim is to strengthen the capacity of the health care system and of professionals to provide care that is adapted to the social conditions of people living in poverty.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pierrehumbert, Raymond
There are a number of crises that a potentially habitable planet must avoid or surmount if its potential is to be realized. These include the runaway greenhouse, loss of atmosphere by chemical or physical processes, and long-lasting global glaciation. In this lecture I will present research on the climate dynamics governing such processes, with particular emphasis on the lessons to be learned from the cases of Early Mars and the Neoproterozoic Snowball Earth.
Virtual Reality: An Emerging Tool to Treat Pain
2010-04-01
burn patients, physical therapy stretching of the newly healing skin helps to counteract the healing skin’s natural contraction as it scars...room, and substitute more calming music and sound effects. The patient interacts with the virtual world, throwing snowballs at objects in the virtual...care (Hoffman, Patterson et al, 2008) and physical therapy (Hoffman, Patterson, Carrougher, 2000; Hoffman, Patterson, Carrougher, Sharar, 2001; Sharar
Benham-Hutchins, Marge; Staggers, Nancy; Mackert, Michael; Johnson, Alisha H; deBronkart, Dave
2017-08-04
Patient-centered care promotes the inclusion of the most prominent and important member of the health care team, the patient, as an active participant in information exchange and decision making. Patient self-management of a chronic disease requires the patient to bridge the gap between multiple care settings and providers. Hospitalizations often disrupt established self-management routines. Access to medical information during hospitalization reflects patients' rights to partner in their own care and has the potential to improve self-management as well as promote informed decision making during and after hospitalization. The objectives of this study were to elicit the perspectives of patients with chronic disease about desired medical information content and access during hospitalization. This exploratory study incorporated a qualitative approach. The online survey included the research team created open and limited response survey, demographic and hospital characteristic questions, and the Patient Activation Measurement instrument (PAM®). Convenience and social media snowball sampling were used to recruit participants through patient support groups, email invitations, listservs, and blogs. The research team employed descriptive statistics and qualitative content analysis techniques. The study sample (n = 34) ranged in age from 20 to 76 (μ = 48; SD = 16.87), Caucasian (91%, n = 31), female (88%, n = 30) and very highly educated (64%, n = 22 were college graduates). The PAM® survey revealed a highly activated sample. Qualitative analysis of the open-ended question responses resulted in six themes: Caring for myself; I want to know everything; Include me during handoff and rounds; What I expect; You're not listening; and Tracking my health information. This study revealed that hospitalized patients want to be included in provider discussions, such as nursing bedside handoff and medical rounds. Only a few participants had smooth transitions from hospital to home. Participants expressed frustration with failures in communication among their providers during and after hospitalization and provider behaviors that interfered with patient provider communication processes. Patients also identified interest in maintaining their own health histories and information but most had to "cobble together" a myriad of methods to keep track of their evolving condition during hospitalization.
2012-01-01
Background Care of children and young people (children) with long-term kidney conditions is usually managed by multidisciplinary teams. Published guidance recommends that whenever possible children with long-term conditions remain at home, meaning parents may be responsible for performing the majority of clinical care-giving. Multidisciplinary team members, therefore, spend considerable time promoting parents' learning about care-delivery and monitoring care-giving. However, this parent-educative aspect of clinicians' role is rarely articulated in the literature so little evidence exists to inform professionals' parent-teaching interventions. Methods/Design This ongoing study addresses this issue using a combination of quantitative and qualitative methods involving the twelve children's kidney units in England, Scotland and Wales. Phase I involves a survey of multidisciplinary team members' parent-teaching interventions using: i) A telephone-administered questionnaire to determine: the numbers of professionals from different disciplines in each team, the information/skills individual professionals relay to parents and the teaching strategies/interventions they use. Data will be managed using SPSS to produce descriptive statistics ii) Digitally-recorded, qualitative group or individual interviews with multidisciplinary team members to explore their accounts of the parent-teaching component of their role. Interviews will be transcribed anonymously and analysed using Framework Technique. Sampling criteria will be derived from analysis to identify one/two unit(s) for subsequent in-depth study Phase II involves six prospective, ethnographic case-studies of professional-parent interactions during parent-teaching encounters. Parents of six children with a long-term kidney condition will be purposively sampled according to their child's age, diagnosis, ethnicity and the clinical care-giving required; snowball sampling will identify the professionals involved in each case-study. Participants will provide signed consent; data gathering will involve a combination of: minimally-obtrusive observations in the clinical setting and families' homes; de-briefing interviews with participants to obtain views on selected interactions; focussed 'verbatim' field-notes, and case-note reviews. Data gathering will focus on communication between parents and professionals as parents learn care-giving skills and knowledge. Interviews will be digitally recorded and transcribed anonymously. Discussion This study involves an iterative-inductive approach and will provide a unique, detailed insight into the social context in which professionals teach and parents learn; it will inform professionals' parent-educative roles, educational curricula, and health care policy PMID:22333296
Swallow, Veronica M; Allen, Davina; Williams, Julian; Smith, Trish; Crosier, Jean; Lambert, Heather; Qizalbash, Leila; Wirz, Lucy; Webb, Nicholas J A
2012-02-14
Care of children and young people (children) with long-term kidney conditions is usually managed by multidisciplinary teams. Published guidance recommends that whenever possible children with long-term conditions remain at home, meaning parents may be responsible for performing the majority of clinical care-giving. Multidisciplinary team members, therefore, spend considerable time promoting parents' learning about care-delivery and monitoring care-giving. However, this parent-educative aspect of clinicians' role is rarely articulated in the literature so little evidence exists to inform professionals' parent-teaching interventions. This ongoing study addresses this issue using a combination of quantitative and qualitative methods involving the twelve children's kidney units in England, Scotland and Wales. Phase I involves a survey of multidisciplinary team members' parent-teaching interventions using:i) A telephone-administered questionnaire to determine: the numbers of professionals from different disciplines in each team, the information/skills individual professionals relay to parents and the teaching strategies/interventions they use. Data will be managed using SPSS to produce descriptive statisticsii) Digitally-recorded, qualitative group or individual interviews with multidisciplinary team members to explore their accounts of the parent-teaching component of their role. Interviews will be transcribed anonymously and analysed using Framework Technique. Sampling criteria will be derived from analysis to identify one/two unit(s) for subsequent in-depth studyPhase II involves six prospective, ethnographic case-studies of professional-parent interactions during parent-teaching encounters. Parents of six children with a long-term kidney condition will be purposively sampled according to their child's age, diagnosis, ethnicity and the clinical care-giving required; snowball sampling will identify the professionals involved in each case-study. Participants will provide signed consent; data gathering will involve a combination of: minimally-obtrusive observations in the clinical setting and families' homes; de-briefing interviews with participants to obtain views on selected interactions; focussed 'verbatim' field-notes, and case-note reviews. Data gathering will focus on communication between parents and professionals as parents learn care-giving skills and knowledge. Interviews will be digitally recorded and transcribed anonymously. This study involves an iterative-inductive approach and will provide a unique, detailed insight into the social context in which professionals teach and parents learn; it will inform professionals' parent-educative roles, educational curricula, and health care policy.
Holdsworth, Clare; Haines, Kimberley J; Francis, Jill J; Marshall, Andrea; O'Connor, Denise; Skinner, Elizabeth H
2015-12-01
Early mobilization in intensive care unit (ICU) is safe, feasible, and beneficial. However, mobilization frequently does not occur in practice. The study objective was to elicit attitudinal, normative, and control beliefs (barriers and enablers) toward the mobilization of ventilated patients, to inform development of targeted implementation interventions. A 9-item elicitation questionnaire was administered electronically to a convenience sample of multidisciplinary staff in a tertiary ICU. A snowball recruitment approach was used to target a sample size of 20 to 25. Two investigators performed word count and thematic analyses independently. Themes were cross-checked by a third investigator. Twenty-two questionnaires were completed. Respondents wrote the most text about disadvantages. Positive attitudinal beliefs included better respiratory function, reduced functional decline, and reduced muscle wasting/weakness. The main negative attitudinal beliefs were that mobilization is perceived as time consuming and poses a risk of line dislodgement/disconnection. Positive control beliefs (enablers) included increased staff availability, positive staff attitudes, engagement, and teamwork. Negative control beliefs (barriers) included unstable patient physiology and negative workplace culture. Intensive care unit staff expressed positive and negative attitudinal, normative, and control beliefs across the spectrum, and disadvantages were most frequently reported. Identified beliefs can be used to inform development of future interventions. Copyright © 2015 Elsevier Inc. All rights reserved.
Rezaei, Fatemeh; Nedjat, Saharnaz; Golestan, Banafsheh; Majdzadeh, Reza
2011-10-01
One of the main strategies to prevent smoking is delaying onset of smoking in adolescents. Thus, identifying the age of smoking and smoking pattern in adolescents gives important knowledge for planning the intervention programs on smoking. Students aged 13-15 years old living in the Northern and the Southern Tehran were selected through two separate snowball samplings. In each area six smokers were considered as the seeds and were asked to introduce a smoker friend. The sampling continued until one hundred study subjects were recruited in each area. Although in the area with wealthier socioeconomic status the age at which smoking started was one year more, the number of days of smoking, number of consumed cigarettes, not willingness to quit smoking, ease of access to cigarettes, mother and siblings smoking were more frequent. In contrast, seeing anti-smoking advertisements, father smoking, teachers smoking and education about the adverse effects of smoking were lower than the area with poorer socioeconomic status. The community level interventions such as not selling cigarettes to juniors, quit smoking help and support, and education of families must be revised. The role of families, through the supervision and control over their children, and parents' avoidance of smoking should be emphasized.
Characteristics and influences of H1N1 communication on college students
Koskan, Alexis; Foster, Caroline; Karlis, Jack; Rose, India; Tanner, Andrea
2014-01-01
Purpose The purpose of this paper is to assess how college students received and responded to H1N1 pandemic emergency preparedness information and to assess college students’ knowledge and attitudes towards H1N1 during the height of the H1N1 epidemic and corresponding public health response to the outbreak. Design/methodology/approach Using a case study approach, the researchers conducted five focus groups at a large Southeastern US university between October 20–29, 2009. Findings In order to effectively communicate emergency preparedness information to college students, universities should rely on interpersonal communication and mediated communication from trusted sources. College students need to understand the health-related emergency, the risk of the emergency, basic steps to avoid it, and only pertinent cues to action. Oversaturation of this information can lead college students to lessen their perceived importance of the disaster prevention information. Research limitations/implications Focus groups were conducted during only two consecutive weeks of the H1N1 epidemic, and snowball sampling may have led to sample bias. Originality/value This research was conducted during the height of the H1N1 pandemic, and is the only study to date that explores college students’ knowledge, attitudes, and behaviors towards H1N1. PMID:25328288
Tamim, Suha R; Grant, Michael M
2016-05-19
This qualitative study aimed at exploring how health professionals use theories and models from the field of education to create ehealth and mhealth education interventions in an effort to provide insights for future research and practice on the development and implementation of health promotion initiatives. A purposeful sample of 12 participants was selected, using criterion and snowballing sampling strategies. Data were collected and analyzed from semistructured interviews, planning materials, and artifacts. The findings revealed that none of the participants used a specific learning theory or an instructional model in their interventions. However, based on participants' description, three themes emerged: (1) connections to behaviorist approaches to learning, (2) connections to cognitivist approaches to learning, and (3) connections to constructivist approaches to learning. Suggested implications for practice are (1) the design of a guidebook on the interplay of learning theories, instructional models, and health education and (2) the establishment of communities of practice. Further research can (1) investigate how learning theories and models intertwine with health behavior theories and models, (2) evaluate how the different instructional strategies presented in this study affect learning outcomes and health behavior change processes, and (3) investigate factors behind the instructional strategies choices made by health professionals. © 2016 Society for Public Health Education.
Novel psychoactive substance and other drug use by young adults in Western australia.
Goggin, Leigh S; Gately, Natalie; Bridle, Russell I
2015-01-01
There is a lack of information regarding the use of novel psychoactive substances (NPS) in Western Australia. The aim of this study was to pilot-test an online survey to obtain data on the prevalence of NPS and other drug use by young Western Australians aged between 18 and 35 years. The Young Adult Drug and Alcohol Survey (YADAS) was a questionnaire deployed online for a period of six months. Participants were recruited via a combined targeted sampling and snowball methodology. There were 472 valid responses. Overall lifetime use of NPS was relatively high (17.6%), while use in the last year was lower (6.6%). These proportions were comparable to that of cocaine use. The most popular NPS were the synthetic cannabinoids. The proportions of respondents drinking alcohol at risky levels, mixing alcohol with energy drinks, and using pharmaceuticals such as ADHD medications for non-medical reasons were high. The YADAS is the first survey to ascertain the prevalence of use of numerous types of NPS in a large sample of young Western Australian adults. The utilization of an online survey methodology yielded valid results as compared to more intensive surveys, and enables researchers greater flexibility in being able to capture current trends.
Peyrovi, Hamid; Parsa-Yekta, Zohreh; Vosoughi, Mohammad Bagher; Fathyian, Nasrollah; Ghadirian, Fataneh
2015-01-01
The extensive nature of the Iraq-Iran war converted to a human tragedy with large casualties; it has affected nursing discipline dramatically. To analyse the history of the wartime experience of Iranian nurses in Iran-Iraq War. The current study was conducted with oral history. The study sample consisted of 13 Iranian nurses who served in the war zones during the wartime. Purposive and snowball sampling were used to recruit the participants. During the face-to-face interviews, participants were asked to describe their experience in the war zones during the war years. Data collection and analysis took place from April to August 2013, when saturation was reached. All interviews were tape recorded and transcribed and then analysed with thematic content analysis. Finally, five themes and 18 subthemes emerged from data analysis of significant statements from 17 interviews. The five emerged themes included (1) 'From margin to centre', (2) 'Development of referral care', (3) 'Personal and professional growth and development', (4) 'The emerging pillar of culture in war nursing' and (5) 'Threats to nursing at the war'. Nursing in Iran at wartime has a difficult path to development. There are powerful implications for clinical practice. It is recommended to continue collection, archiving and analysing the wartime experiences of Iranian nurses.
Family-focused practice within a recovery framework: practitioners' qualitative perspectives.
Ward, B; Reupert, A; McCormick, F; Waller, S; Kidd, S
2017-03-24
Family-focused practice (FFP) is an effective approach to supporting individuals with mental illness. 'Recovery' is also central to contemporary mental health care. However, there is a dearth of evidence about how the two concepts are related and subsequently implemented in practice. The aim of this study was to explore practitioners' understandings and practices of FFP within a recovery framework. Purposive/snowball sampling was used to recruit and conduct qualitative interviews with 11 mental health practitioners in rural Australia. Concurrent sampling and data collection were informed by thematic analysis and continued until data saturation was reached. Participants found it difficult to articulate their understandings of FFP within a recovery framework. Nonetheless they were able to describe practices that embodied family-focused recovery. Barriers to such practices included medical models of care, where there are often a shortage of skilled staff and high demands for care. Stigma (self and from others) and confidentiality were also identified as barriers to involving family members in recovery focused care. Family-focused recovery care is a priority in many high-income countries. A family-focused recovery framework is needed to assist service planners, practitioners, family members and those with mental health needs and ensure such care is embedded within practice guidelines.
Sandle, Meghan; Tuohy, P
2017-04-28
The contraceptive implant Jadelle, along with other types of long-acting reversible contraception, is thought to be an ideal choice for young people wanting to avoid pregnancy, however, uptake is low. This study aimed to explore the attitudes and experiences of health professionals regarding the use of Jadelle in teenagers. Semi-structured interviews were carried out with professionals providing contraceptive services to young people. Sampling was by identifying key informants and subsequent snowball sampling. Interviews were transcribed and main themes identified. Ten interviews were done with service providers, including midwives, doctors and nurses. Five main themes were identified: characteristics of young people, contraceptive services, positive features of Jadelle, barriers to contraception and individual choice. Jadelle was seen as a good option due to its effectiveness, discreetness and user independence. Barriers for young people obtaining Jadelle included cost, access, fear of procedure and lack of appropriate services. Health professionals had a range of experiences using the contraceptive implant Jadelle. Most felt that Jadelle was a good choice for young people. Improvements to access were identified, including reduced cost and more youth-friendly services, which may lead to increased Jadelle uptake and a subsequent reduction in unintended teenage pregnancies.
Varghese, Shainy B; Phillips, Carolyn A
2009-12-01
The overall goal of this study was to explore and describe the perceptions of advanced practice nurses (APNs) about caring while providing primary care using telehealth technology. This study used naturalistic inquiry methodology to elicit the subjective perceptions and reflections of a sample of APNs about how they convey caring in the context of telehealth. Thirteen APNs, selected by purposive and snowball sampling, participated in the study. The data for the study consisted of interviews conducted by e-mail using a semistructured interview guide. Data analysis used the constant comparison method; rigor and trustworthiness of the study procedures were established using the criteria of credibility, confirmability, dependability, and transferability. The findings of this study revealed that the APNs conveyed caring to their telehealth patients by (1) being with them, (2) personifying the images, and (3) possessing certain attributes. The major constructs that emerged from the data together formed a model of how APNs conveyed caring in telehealth. The findings provide insights and increase the understanding of how caring in telehealth was perceived by APNs. The findings of the study can make important contributions in improving our profession's preparation of future telehealth APNs. The study findings also can lend themselves to developing an instrument to measure caring in telehealth. The study findings also contribute to the nursing literature in a number of ways.
Gheorghe, Iuliana Raluca; Gheorghe, Consuela-Mădălina; Purcărea, Victor Lorin
2018-01-01
Nowadays, the competition registered on the Romanian markets regarding the activity of private ophthalmology organizations has raised their interest in developing consumer-oriented strategies. The key factor that assures a differentiation as well as a competitive advantage is the service quality from a marketing perspective. From a marketing perspective, service quality is measured as a perceived discrepancy between the consumers' expectations and was actually performed in health care services. The most widely and validated measurement is the SERVQUAL scale. However, a variety of SERVQUAL scales have been applied in different health care environments without taking into consideration the specialty of the health care service. Thus, the objective of this paper was to measure the service quality in the Romanian ophthalmology private organizations using the SERVQUAL measurement, by identifying the SERVQUAL dimensions, which register the highest and the lowest gap scores. The instrument for data collection was the SERVQUAL self-administered questionnaire that consisted of 22 items measured on a 5-point Likert scale. The sample size encompassed 100 participants and the sampling technique was the snowball. The internal consistency, validity and the reliability of the SERVQUAL scale was determined by the Cronbach's alpha coefficients and factor analysis. The SERVQUAL questionnaire focused on 5 dimensions (tangibles, reliability, assurance, empathy and responsiveness) and each dimension, in its turn, was characterized by different items. The mean age of the participants was 49.52 years, with a mean income of 3031 Romanian Currency and the mean period of wearing eyeglasses was 5 years (±2). Further, there were 47% females and 53% males. The overall internal consistency of the SERVQUAL scale, as well as the dimensions' internal consistency were all above 0.7 and the factor analysis revealed that the items loaded properly on each dimension. Moreover, the gap scores of the SERVQUAL scale's dimensions pinpointed that the highest gap score was registered by the Tangibles dimension and the lowest gap score was registered by the Reliability dimension. Performing the ophthalmology service right the first time, contributes significantly to the improvement of the marketing effectiveness and the operating efficiency.
Gheorghe, Iuliana Raluca; Gheorghe, Consuela-Mădălina; Purcărea, Victor Lorin
2018-01-01
Nowadays, the competition registered on the Romanian markets regarding the activity of private ophthalmology organizations has raised their interest in developing consumer-oriented strategies. The key factor that assures a differentiation as well as a competitive advantage is the service quality from a marketing perspective. Objectives: From a marketing perspective, service quality is measured as a perceived discrepancy between the consumers’ expectations and was actually performed in health care services. The most widely and validated measurement is the SERVQUAL scale. However, a variety of SERVQUAL scales have been applied in different health care environments without taking into consideration the specialty of the health care service. Thus, the objective of this paper was to measure the service quality in the Romanian ophthalmology private organizations using the SERVQUAL measurement, by identifying the SERVQUAL dimensions, which register the highest and the lowest gap scores. Materials and methods: The instrument for data collection was the SERVQUAL self-administered questionnaire that consisted of 22 items measured on a 5-point Likert scale. The sample size encompassed 100 participants and the sampling technique was the snowball. The internal consistency, validity and the reliability of the SERVQUAL scale was determined by the Cronbach’s alpha coefficients and factor analysis. The SERVQUAL questionnaire focused on 5 dimensions (tangibles, reliability, assurance, empathy and responsiveness) and each dimension, in its turn, was characterized by different items. Results: The mean age of the participants was 49.52 years, with a mean income of 3031 Romanian Currency and the mean period of wearing eyeglasses was 5 years (±2). Further, there were 47% females and 53% males. The overall internal consistency of the SERVQUAL scale, as well as the dimensions’ internal consistency were all above 0.7 and the factor analysis revealed that the items loaded properly on each dimension. Moreover, the gap scores of the SERVQUAL scale’s dimensions pinpointed that the highest gap score was registered by the Tangibles dimension and the lowest gap score was registered by the Reliability dimension. Conclusions: Performing the ophthalmology service right the first time, contributes significantly to the improvement of the marketing effectiveness and the operating efficiency. PMID:29796435
Palaeomagnetism of the Late Neoproterozoic of Ella O, North-East Greenland
NASA Astrophysics Data System (ADS)
Kilner, B.; Mac Niocaill, C.; Stouge, S.; Harper, D.
2004-12-01
Neoproterozoic to lower Ordovician sediments outcrop in a N-S trending band in the fjord region of North-East Greenland. The sequence comprises, in ascending order, the Eleonore Bay Group, the Tillite Group and the Canyon and Spiral Creek Formations. The Eleonore Bay Group is thought to be Upper Riphean in age and consists of cherty limestone and dolomite capped by red siltstone. The overlying Tillite Group contains two tillite packages separated by an intertillite which comprises marine siltstone and sandstone. The Canyon and Spiral Creek Formation consist of evaporitic red siltstone, with chert-rich horizons and some dolomite. The Spiral Creek Formation is overlain by a basal Cambrian quartzite. 500 samples were collected from the late Precambrian succession on the island of Ella O in Kong Oscars Fjord. Sampling was aimed in particular at red beds and other likely magnetic targets. The specimens were demagnetised using progressive alternating frequency and thermal techniques and typically revealed a multi-component remanence structure. A majority of the specimens carry a low stability (generally < 20mt, < 250° ) component, directed north and steeply down. This closely resembles present Earth's field. Demagnetisation of the Eleonore Bay Group reveals a high stability component directed south and shallow down, with an opposing component north and up. After tilt correction the mean direction yields a palaeolatitude of 4° . This component passes field tests, and is interpreted as primary. Magnetic characteristics in the Tillite Group are distinct from those of the Eleonore Bay Group. The Lower Tillite Formation carries an east directed shallow down component. The palaeolatitude derived from this direction indicates low latitude deposition for the glacial rocks above the Eleonore Bay Group. The Upper Tillite Formation carries a high stability component directed steeply upwards. Specimens from a limited pilot study pass reversal and fold tests, but further experiments are required to verify the result. If confirmed, this would indicate a hiatus between the lower and upper tillites. It also suggests that the Upper Tillite, which potentially correlates with the 630Ma 'snowball' Earth event, was deposited at high latitude. This would be the first confirmation that the late Neoproterozoic Marinoan glaciation extended over a broad range of latitudes.
Jelsma, Jennifer; Maart, Soraya; Eide, Arne; Toni, Mzolisi; Loeb, Mitch
2008-01-01
This study was to establish whether there was a difference in the characteristics of people who received a disability grant and those who did not in rural and urban samples of isiXhosa-speaking people with disability in South Africa. The sample was a convenience sample and was identified through a 'snowballing' process. A demographic survey and isiXhosa versions of the International Classification of Functioning, Disability and Health (ICF) and EQ-5D, a health-related quality of life measure were utilized. The sample consisted of 244 rural and 61 urban respondents, demonstrating a preponderance of physical disabilities. The groups who received or did not receive grants were equivalent in terms of age, gender, marital status and employment status. A significantly higher proportion of rural dwellers accessed the grant. The grant holders displayed significantly more problems related to mobility and to technology and policies and services relating to mobility and transport. Those who did not receive grants reported more barriers with regard to the attitudes of health workers but not with regard to any other aspect of social support. The majority of men and women with disability identified in this study received the grant, whether or not they lived in remote rural or in urban areas. As there were few differences between the groups, it is likely that several non-grant holders might qualify if they were informed of the grant and applied. The role of medical doctors as 'gatekeepers' to the grant might need to be examined.
Current Trends in Metric Conversion in the United States: Potential Trouble for National Defense.
1980-05-01
measures in the United States appears inevitable, but is being prolonged due to present legisla- *tion which allows each industrial sector to convert...centralized government planning and leadership toward metrication in the shortest possible time. II. Problem: Spurred by the automotive industry , voluntary...conversion among major U.S. industries is snowballing while public resistance to met- rication is stiffening. This confrontation threatens to
Forming Rb(+) snowballs in the center of He nanodroplets.
Theisen, Moritz; Lackner, Florian; Ernst, Wolfgang E
2010-12-07
Helium nanodroplets doped with rubidium atoms are ionized by applying a resonant two-step ionization scheme. Subsequent immersion of rubidium ions is observed in time-of-flight mass spectra. While alkali-metal atoms usually desorb from the surface of a helium nanodroplet upon electronic excitation, rubidium in its excited 5(2)P(1/2) state provides an exception from this rule (Auböck et al., Phys. Rev. Lett., 2008, 101, 35301). In our new experiment, Rb atoms are selectively excited either to the 5(2)P(1/2) or to the 5(2)P(3/2) state. From there they are ionized by a laser pulse. Time-of-flight mass spectra of the ionization products reveal that the intermediate population of the 5(2)P(1/2) state does not only make the ionization process Rb-monomer selective, but also gives rise to a very high yield of Rb(+)-He(N) complexes. Ions with masses of up to several thousand amu have been monitored, which can be explained by an immersion of the single Rb ion into the He nanodroplet, where most likely a snowball is formed in the center of the He nanodroplet. As the most stable position for an ion is in the center of a He nanodroplet, our results agree well with theory.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Issaoui, Noureddine, E-mail: issaoui-noureddine@yahoo.fr; Abdessalem, Kawther; Ghalla, Houcine
2014-11-07
The solvation of the Na{sup +} ion in helium clusters has been studied theoretically using optimization methods. A many-body empirical potential was developed to account for Na{sup +}–He and polarization interactions, and the most stable structures of Na{sup +}He{sub n} clusters were determined using the basin-hopping method. Vibrational delocalization was accounted for using zero-point energy corrections at the harmonic or anharmonic levels, the latter being evaluated from quantum Monte Carlo simulations for spinless particles. From the static perspective, many-body effects are found to play a minor role, and the structures obtained reflect homogeneous covering up to n = 10, followedmore » by polyicosahedral packing above this size, the cluster obtained at n = 12 appearing particularly stable. The cationic impurity binds the closest helium atoms sufficiently to negate vibrational delocalization at small sizes. However, this snowball effect is obliterated earlier than shell completion, the nuclear wavefunctions of {sup 4}He{sub n}Na{sup +} with n = 5–7, and n > 10 already exhibiting multiple inherent structures. The decrease in the snowball size due to many-body effects is consistent with recent mass spectrometry measurements.« less
Abrupt Climate Transition of Icy Worlds from Snowball to Moist or Runaway Greenhouse
NASA Astrophysics Data System (ADS)
Yang, J.; Ding, F.; Ramirez, R. M.; Peltier, W. R.; Hu, Y.; Liu, Y.
2017-12-01
Ongoing and future space missions aim to identify potentially habitable planets in our Solar System and beyond. Planetary habitability is determined not only by a planet's current stellar insolation and atmospheric properties, but also by the evolutionary history of its climate. It has been suggested that icy planets and moons become habitable after their initial ice shield melts as their host stars brighten. Here we show from global climate model simulations that a habitable state is not achieved in the climatic evolution of those icy planets and moons that possess an inactive carbonate-silicate cycle and low concentrations of greenhouse gases. Examples for such planetary bodies are the icy moons Europa and Enceladus, and certain icy exoplanets orbiting G and F stars. We find that the stellar fluxes that are required to overcome a planet's initial snowball state are so large that they lead to significant water loss and preclude a habitable planet. Specifically, they exceed the moist greenhouse limit, at which water vapour accumulates at high altitudes where it can readily escape, or the runaway greenhouse limit, at which the strength of the greenhouse increases until the oceans boil away. We suggest that some icy planetary bodies may transition directly to a moist or runaway greenhouse without passing through a habitable Earth-like state.
Abrupt climate transition of icy worlds from snowball to moist or runaway greenhouse
NASA Astrophysics Data System (ADS)
Yang, Jun; Ding, Feng; Ramirez, Ramses M.; Peltier, W. R.; Hu, Yongyun; Liu, Yonggang
2017-08-01
Ongoing and future space missions aim to identify potentially habitable planets in our Solar System and beyond. Planetary habitability is determined not only by a planet's current stellar insolation and atmospheric properties, but also by the evolutionary history of its climate. It has been suggested that icy planets and moons become habitable after their initial ice shield melts as their host stars brighten. Here we show from global climate model simulations that a habitable state is not achieved in the climatic evolution of those icy planets and moons that possess an inactive carbonate-silicate cycle and low concentrations of greenhouse gases. Examples for such planetary bodies are the icy moons Europa and Enceladus, and certain icy exoplanets orbiting G and F stars. We find that the stellar fluxes that are required to overcome a planet's initial snowball state are so large that they lead to significant water loss and preclude a habitable planet. Specifically, they exceed the moist greenhouse limit, at which water vapour accumulates at high altitudes where it can readily escape, or the runaway greenhouse limit, at which the strength of the greenhouse increases until the oceans boil away. We suggest that some icy planetary bodies may transition directly to a moist or runaway greenhouse without passing through a habitable Earth-like state.
Patterns of NPS Use and Risk Reduction in Slovenia.
Sande, Matej; Paš, Mina; Nahtigal, Klara; Šabić, Simona
2018-01-15
The following study presents factors influencing the decision to use/not to use new psychoactive substances (NPS), various patterns of NPS use, the problems experienced by users, and the methods for reducing the risks associated with NPS use. The study seeks to provide an in-depth look into the characteristics of NPS use and support the planning of targeted interventions in the field of NPS. The study involved 19 in-depth interviews carried out with 25 individuals divided into three subsamples in order to gain insight into the various experiences of NPS users. The interviews were conducted in Slovenia between December 2013 and October 2014. The sample was obtained by using the convenience sampling and snowball sampling methods. The main pattern of NPS use determined by the study concerned synthetic cathinones, specifically 3-MMC, with binge use spanning several days being a prominent feature. The main risks involving NPS use were: mixing various drugs, inappropriate dosing, lack of information prior to use, and the use of unknown substances. Several users spoke about effective strategies for reducing risks, such as obtaining information beforehand, using one's own implements and using only small quantities of unknown substances. Conclusions/Importance: The study revealed various factors based on which users decide to use NPS. Furthermore, users reported a number of problems resulting from NPS use, while risk reduction strategies are employed to a much lesser extent. Based on the results obtained, specific intervention efforts concerning NPS use and targeting specific groups of younger users were designed.
Reiss, K; Makarova, N; Spallek, J; Zeeb, H; Razum, O
2013-06-01
In 2009, 19.6% of the population of Germany either had migrated themselves or were the offspring of people with migration experience. Migrants differ from the autochthonous German population in terms of health status, health awareness and health behaviour. To further investigate the health situation of migrants in Germany, epidemiological studies are needed. Such studies can employ existing databases which provide detailed information on migration status. Otherwise, onomastic or toponomastic procedures can be applied to identify people with migration background. If migrants have to be recruited into an epidemiological study, this can be done register-based (e. g., data from registration offices or telephone lists), based on residential location (random-route or random-walk procedure), via snowball sampling (e. g., through key persons) or via settings (e. g., school entry examination). An oversampling of people with migration background is not sufficient to avoid systematic bias in the sample due to non-participation. Additional measures have to be taken to increase access and raise participation rates. Personal contacting, multilingual instruments, multilingual interviewers and extensive public relations increase access and willingness to participate. Empirical evidence on 'successful' recruitment strategies for studies with migrants is still lacking in epidemiology and health sciences in Germany. The choice of the recruitment strategy as well as the measures to raise accessibility and willingness to participate depend on the available resources, the research question and the specific migrant target group. © Georg Thieme Verlag KG Stuttgart · New York.
Burt, Richard D; Thiede, Hanne
2014-11-01
Respondent-driven sampling (RDS) is a form of peer-based study recruitment and analysis that incorporates features designed to limit and adjust for biases in traditional snowball sampling. It is being widely used in studies of hidden populations. We report an empirical evaluation of RDS's consistency and variability, comparing groups recruited contemporaneously, by identical methods and using identical survey instruments. We randomized recruitment chains from the RDS-based 2012 National HIV Behavioral Surveillance survey of injection drug users in the Seattle area into two groups and compared them in terms of sociodemographic characteristics, drug-associated risk behaviors, sexual risk behaviors, human immunodeficiency virus (HIV) status and HIV testing frequency. The two groups differed in five of the 18 variables examined (P ≤ .001): race (e.g., 60% white vs. 47%), gender (52% male vs. 67%), area of residence (32% downtown Seattle vs. 44%), an HIV test in the previous 12 months (51% vs. 38%). The difference in serologic HIV status was particularly pronounced (4% positive vs. 18%). In four further randomizations, differences in one to five variables attained this level of significance, although the specific variables involved differed. We found some material differences between the randomized groups. Although the variability of the present study was less than has been reported in serial RDS surveys, these findings indicate caution in the interpretation of RDS results. Copyright © 2014 Elsevier Inc. All rights reserved.
Triangular Assessment of the Etiology of Induced Abortion in Iran: A Qualitative Study
Motaghi, Zahra; Keramat, Afsaneh; Shariati, Mohammad; Yunesian, Masud
2013-01-01
Background About 46 million induced abortions occur in the world annually. The studies have reported 80000 cases of induced abortions in Iran annually. Objectives This qualitative study was conducted to identify the causes of unsafe abortion in Iran from the standpoint of three groups of experts, women with a history of abortion or unwanted pregnancy and service providers. Patients and Methods A total of 72 in-depth semi structured interviews were conducted in 2012 in Tehran and Shahroud. After coordination with 8 experts, sampling from them was done using the Snowballing method in their offices. Sampling from 28 married and 10 engaged women with a history of unwanted pregnancy or unsafe abortion and 12 providers was done in health care centers and a in number of gynecologists’ and midwives’ offices. Sampling from women with a history of unwanted pregnancy or unsafe abortion such as single women, HIV positive women and drug users, and women who had sexual intercourse for money was started by referring to the social rehabilitation center for women and continued using the snowballing method due to difficulties in accessing them. Participants were from different ethnic groups including Fars, Gilaks, Mazandarani, Arab, Azerbaijani, and Lor. Content analysis was performed on collected data. Results Based on the results of the interviews, participants have abortion for following reasons: 1. Wanted pregnancy (sub categories: fetal abnormalities, Concern about fetal health and lack of trust to prenatal diagnostic methods, Fetal sex, Lack of independent and free decision making regarding pregnancy in women, 2. Unwanted pregnancy (sub-categories: Socio-economic factors, Beliefs and feelings, Lack of information about family planning) 3. Predisposing factors (sub-categories: Lack of information on religious aspects of abortion, Easy access to easy abortion methods). Some people, despite having unwanted pregnancy due to social, economic, cultural and family grounds, continued their pregnancy and did not have an abortion for the following reasons: Religious beliefs, Beliefs (fear of punishment in the afterlife and believing in fate) , Attachment to the unborn baby, Influence of the other people’s opinions (physician, mother or spouse) Late diagnosis of pregnancy, Unsuccessful abortion attempts (Self-treatment, Unsuccessful medical abortion), Economic weakness and arbitrary treatment. Conclusions In the present study, women who continued their pregnancy despite being unwanted were also interviewed. Although they had the same social, economic, cultural, and family problems as women with a history of unsafe abortion and had easy access to abortion, analysis showed that the difference in religious beliefs between the two groups was the most important factor that led women to choose two different approaches. The authors believe that in-depth analysis of people’s beliefs and opinions in this regard and correction of false beliefs plays a crucial role in decreasing the rate of unsafe abortion. PMID:24719694
[Inefficacy of self-regulation of alcohol advertisements: a systematic review of the literature].
Vendrame, Alan; Pinsky, Ilana
2011-06-01
The most recent scientific literature indicates that alcohol advertising influences behavior, particularly early and higher alcohol consumption by children and adolescents. From a public health perspective, alcohol advertising should be restricted. In many countries, as well as in Brazil, limits to alcohol advertising are established by industry self-regulation (e.g. controlled by the advertising community itself). We examined in this review all articles on the subject of industry self-regulation of alcohol advertising published in the international literature. A systematic literature review was conducted on articles investigating the effectiveness of self-regulation of alcohol advertisings. The search was conducted in Medline, SciELO, Camy and Google Scholar, between the years of 1991 and 2010. In addition, the "snowball" technique for the indication of the main authors on the subject was employed. From the articles found, 11 focused on the subject discussed here. The set of articles obtained indicates that industry self-regulation of alcohol advertising does not show evidence of efficacy. In other words, such a regulation does not prevent, for instance, alcohol advertising directed at children and adolescents. Further measures should be considered for the control and the broadcast of alcohol advertising, such as independent monitoring, legal control.
Cumber, Samuel Nambile
2016-01-01
Introduction Street children in Cameroon are adolescents, vulnerable to sexually transmitted infections (STIs) and HIV and/or AIDS. The level of knowledge and practice of condom use among this population is unknown. Objective of the study To assess the knowledge, practice and barriers to condom use in Cameroon. Materials and methods The study was an analytical cross-sectional survey conducted in 2015. Questionnaires were administered to street children in a quiet location. Recruitment was made using the snowball technique with the help of peers. Results More than 90% of participants knew of condoms, but only about 6% reported to have used a condom during their last sexual encounter. Most of the participants did not know that condoms could prevent HIV; only a few (15.5%) knew about this. Conclusion Street adolescents in Cameroon seem to know about condoms, but have insufficient information on the importance of their regular use. The main barriers for the low practice of condom use reported by this population were the following: condoms hinder sexual pleasure; are costly; and it is embarrassing to buy, use or propose to use a condom. PMID:29568619
Using statistical correlation to compare geomagnetic data sets
NASA Astrophysics Data System (ADS)
Stanton, T.
2009-04-01
The major features of data curves are often matched, to a first order, by bump and wiggle matching to arrive at an offset between data sets. This poster describes a simple statistical correlation program that has proved useful during this stage by determining the optimal correlation between geomagnetic curves using a variety of fixed and floating windows. Its utility is suggested by the fact that it is simple to run, yet generates meaningful data comparisons, often when data noise precludes the obvious matching of curve features. Data sets can be scaled, smoothed, normalised and standardised, before all possible correlations are carried out between selected overlapping portions of each curve. Best-fit offset curves can then be displayed graphically. The program was used to cross-correlate directional and palaeointensity data from Holocene lake sediments (Stanton et al., submitted) and Holocene lava flows. Some example curve matches are shown, including some that illustrate the potential of this technique when examining particularly sparse data sets. Stanton, T., Snowball, I., Zillén, L. and Wastegård, S., submitted. Detecting potential errors in varve chronology and 14C ages using palaeosecular variation curves, lead pollution history and statistical correlation. Quaternary Geochronology.
NASA Astrophysics Data System (ADS)
Leib, Steven M.
This was a mixed-methods exploratory study to investigate association between environmental context and the implementation status of Safety Management Systems (SMS) at airports in Greater China. Using a framework of Institutional Theory, this study looked at three regions of Greater China and explored internal and external environments of SMS at airports within each region. It used ICAO standards to evaluate the implementation status of SMS at those airports based on the perceptions of 126 participants. This research also employed snowballing technique to spread a survey tool to participants in Greater China through several key gatekeepers, and then applied the Delphi method for interviews with key gatekeepers themselves. Analysis of the data suggested several associations between various sub-concepts of the external environment and different components of SMS in the three regions. In addition, the data suggested a relationship between the internal environment as a whole and the overall status of SMS implementation in each region. Lastly, the study makes several recommendations for future research regarding global standards implemented in local environments, the evaluation of SMS implementation status, and the theoretical implications of this study.
Gosain, Mudita; Goel, Akhil D; Kharya, Pradeep; Agarwal, Ramesh; Amarchand, Ritvik; Rai, Sanjay K; Kapoor, Suresh; Paul, Vinod K; Krishnan, Anand
2017-10-01
Planning a comprehensive program addressing neonatal mortality will require a detailed situational analysis of available neonatal-specific health infrastructure. We identified facilities providing essential and sick neonatal care (ENC, SNC) by a snowballing technique in Ballabgarh Block. These were assessed for infrastructure, human resource and equipment along with self-rated competency of the staff and compared with facility-based or population-based norms. A total of 35 facilities providing ENC and 10 facilities for SNC were identified. ENC services were largely in the public-sector domain (68.5% of births) and were well distributed in the block. SNC burden was largely being borne by the private sector (66% of admissions), which was urban-based. The private sector and nurses reported lower competency especially for SNC. Only 53.9% of government facilities and 17.5% of private facilities had a fully equipped newborn care corner. Serious efforts to reduce neonatal mortality would require major capacity strengthening of the health system, including that of the private sector. © The Author [2017]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com
Managing equipment innovations in mining: A review.
Trudel, Bryan; Nadeau, Sylvie; Zaras, Kazimierz; Deschamps, Isabelle
2015-01-01
Technological innovations in mining equipment have led to increased productivity and occupational health and safety (OHS) performance, but their introduction also brings new risks for workers. The aim of this study is to provide support for mining industry managers who are required to reconcile equipment choices with OHS and productivity. Examination of the literature through interdisciplinary digital databases. Databases were searched using specific combinations of keywords and limited to studies dating back no farther than 1992. The ``snowball'' technique was also used to examining the references listed in research articles initially identified with the databases. A total of 19 contextual factors were identified as having the potential to influence the OHS and productivity leverage of equipment innovations. The most often cited among these factors are the level of training provided to the equipment operators, operator experience and age, supervisor leadership abilities, and maintaining good relations within work crews. Interactions between these factors are not discussed in mining innovation literature. It would be helpful to use a systems thinking approach which incorporates interaction between relevant actors and factors to define properly the most sensitive aspects of innovation management as it applies to mining equipment.
Pinsky, Ilana; El Jundi, Sami A R J
2008-12-01
Problems related to alcohol consumption are frequent, especially among the youth population. We analyzed advertisement as one of several modifiable factors with impact over alcohol consumption. The authors carried out a literature review within Medline, SciELO, PsychoInfo and Google Scholar databases between 1990 and 2008, retrieving studies with different approaches of the alcohol advertisement impact on consumption. Besides, a ' snowball' technique was applied to identify the most proficuous authors on the matter. Over a hundred papers were initially selected. The overall set of papers indicate that factors such as exposition to the advertising and attractiveness of the alcoholic beverage advertising are related with greater expectation of future consumption and with a higher and precocious consumption of alcohol, specially among adolescents and young adults. Despite methodological difficulties, recent econometrical studies indicate that reduction and/or banishment of advertising would decrease alcohol consumption. We also consider issues about the neurophysiology of decision making process and the freedom of choice in the context of exposition to advertisements. The current knowledge on the matter strongly suggests that a reduction of the exposition to alcohol advertisements impacts on its consumption, mainly among young populations.
Mboua, C P; Touko, A
2016-11-01
The scientific literature about disabled people has stressed their high exposure to social exclusion and marginalization, linked to ways of thinking and representations about them. In the area of HIV/AIDS, this marginalization, which results in higher levels of self-stigmatization and especially in inequalities in prevention, continues to put disabled people at high risk of HIV infection. The current study, conducted with a socioepidemiological and behavioral approach, included 317 people with hearing disabilities, recruited through purposive sampling combined with a snowball approach. Participants, after providing informed consent in accordance with the declaration of Helsinki, completed a questionnaire and underwent HIV screening. The results showed a high rate of early sexual intercourse and a high prevalence of HIV, associated with their many risk factors and vulnerability. The analysis also revealed that social marginalization, erroneous beliefs, lack of communication and more generally of appropriate prevention adapted to them, a high rate of multiple partners, a low rate of condom use, psychosexual violence, and difficulties in negotiating social relations, particularly those of sexual relations, are the principal factors of vulnerability and risk.
Iron-Segev, Sharon; Lusweti, Janerose Nasimiyu; Kamau-Mbuthia, Elizabeth; Stark, Aliza H
2018-04-01
Geophagia, the deliberate consumption of rocks, soil, or clay, is prevalent in developing countries, particularly sub-Saharan Africa. Health risks associated with this behavior include parasitosis, heavy metal poisoning, nutrient deficiencies, and poor birth outcomes. This pilot study was designed to reduce geophagic practices and improve nutrition among rural Kenyan women. The researchers used snowball sampling to recruit participants (n = 135; aged 15-49 years) from low socioeconomic areas who consumed geophagic materials. Interviews were carried out before and after a nutrition intervention implemented by trained community health volunteers. Nutrition education focusing on geophagia significantly (P < .001) decreased the practice in 77% of participants. Postintervention interviews also demonstrated substantial improvement in understanding the concept of making half the plate vegetables using the healthy plate model. Nutrition education can be useful for reducing geophagia (a largely ignored, unsafe dietary behavior) and enhancing nutritional knowledge in African women. Copyright © 2017 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.
Iravani, Mina; Janghorbani, Mohsen; Zarean, Ellahe; Bahrami, Masod
2016-02-01
Evidence based practice is an effective strategy to improve the quality of obstetric care. Identification of barriers to adaptation of evidence-based intrapartum care is necessary and crucial to deliver high quality care to parturient women. The current study aimed to explore barriers to adaptation of evidence-based intrapartum care from the perspective of clinical groups that provide obstetric care in Iran. This descriptive exploratory qualitative research was conducted from 2013 to 2014 in fourteen state medical training centers in Iran. Participants were selected from midwives, specialists, and residents of obstetrics and gynecology, with a purposive sample and snowball method. Data were collected through face-to-face semi-structured in-depth interviews and analyzed according to conventional content analysis. Data analysis identified twenty subcategories and four main categories. Main categories included barriers were related to laboring women, persons providing care, the organization environment and health system. The adoption of evidence based intrapartum care is a complex process. In this regard, identifying potential barriers is the first step to determine and apply effective strategies to encourage the compliance evidence based obstetric care and improves maternity care quality.
Yu, Dorothy; Hatala, Andrew R; Reimer, Joss; Lorway, Rob
2017-12-22
Despite decreased rates of HIV infection in Winnipeg, syphilis incidence continues to rise. Communities of men who have sex with men shoulder much of this burden of illness. This qualitative study aimed to better understand the co-evolution of HIV and syphilis in Winnipeg through a series of interviews with gay men. Eighteen individuals were recruited through advertising in sexual health centres and through subsequent snowball sampling. Thematic interpretive analysis and inductive reasoning were used to find individual and shared group meanings. We found that HIV formed the contextual ground on which sexual decision-making was made, with three main themes emerging during interviews: 1) bacterial STI transience being contrasted against HIV permanence; 2) syphilis being 'dirty' versus HIV carrying significant stigma, though being spared the label of uncleanliness; and 3) the role of pleasure and intimacy in sexual health decision-making. Based on these findings, we recommend further exploration to develop more effective strategies around syphilis prevention, in particular with regards to the longer-term illness ramifications and its relationship to HIV transmission.
Shadish, William R; Lecy, Jesse D
2015-09-01
This article looks at the impact of meta-analysis and then explores why meta-analysis was developed at the time and by the scholars it did in the social sciences in the 1970s. For the first problem, impact, it examines the impact of meta-analysis using citation network analysis. The impact is seen in the sciences, arts and humanities, and on such contemporaneous developments as multilevel modeling, medical statistics, qualitative methods, program evaluation, and single-case design. Using a constrained snowball sample of citations, we highlight key articles that are either most highly cited or most central to the systematic review network. Then, the article examines why meta-analysis came to be in the 1970s in the social sciences through the work of Gene Glass, Robert Rosenthal, and Frank Schmidt, each of whom developed similar theories of meta-analysis at about the same time. The article ends by explaining how Simonton's chance configuration theory and Campbell's evolutionary epistemology can illuminate why meta-analysis occurred with these scholars when it did and not in medical sciences. Copyright © 2015 John Wiley & Sons, Ltd.
A qualitative analysis of multi-level barriers to HIV testing among women in Lebanon.
Clark, Kirsty A; Keene, Danya E; Pachankis, John E; Fattal, Omar; Rizk, Nesrine; Khoshnood, Kaveh
2017-09-01
While the number of HIV cases in the Middle East and North Africa region is low compared to other regions, recent studies show that incidence is increasing especially among high-risk populations; in particular, little is known about women and HIV in the region. Through semi-structured interviews with sexual healthcare providers and staff at non-governmental organisations, we sought to understand barriers to HIV testing among women in Lebanon. Using snowball sampling, key informants were recruited from greater Beirut (12 physicians, 9 non-governmental organisation staff). Data were analysed using a grounded theory framework. Findings identified barriers to HIV testing among women at each level of an adapted social-ecological model (i.e. social-cultural barriers, policy barriers, interpersonal healthcare provider barriers and intrapersonal barriers). Primary findings include the culture of sex as taboo; lack of sexual health education among women; fear of disclosing HIV testing and diagnosis; financial barriers linked to stigmatising insurance policies; and provider attitudes towards women. Findings can be used to inform HIV-related sexual health interventions at multiple levels for women in Lebanon and the greater region.
Manchaiah, Vinaya; Danermark, Berth; Vinay; Ahmadi, Tayebeh; Tomé, David; Krishna, Rajalakshmi; Germundsson, Per
2015-01-01
The current study was aimed at understanding the social representation of hearing aids in India, Iran, Portugal, and the United Kingdom. We also compared these results to explore the cross-cultural differences and similarities among these countries. The study involved a cross-sectional design, and the data were collected from four different countries using the snowball sampling method. Data were analyzed using a content analysis to identify the most-similar categories of responses reported, a co-occurrences analysis to see which of these categories are reported commonly, and a chi-square analysis to study if there was any association between positive, neutral, and negative connotations among participants in different countries. The current study revealed four different social representations of hearing aids from India, Iran, Portugal, and the United Kingdom, and also a global index. The study results provide very useful insights into how hearing aids are represented in the society. These findings may have important implications for public education and also for manufacturers from the viewpoint of designing and marketing hearing aids in different countries.
Thinking the "unthinkable": why Philip Morris considered quitting.
Smith, E A; Malone, R E
2003-06-01
To investigate the genesis and development of tobacco company Philip Morris's recent image enhancement strategies and analyse their significance. Internal Philip Morris documents, made available by the terms of the Master Settlement Agreement between the tobacco companies and the attorneys general of 46 states, and secondary newspaper sources. Searches of the Philip Morris documents website (www.pmdocs.com) beginning with terms such as "image management" and "identity" and expanding as relevant new terms (consultant names, project names, and dates), were identified, using a "snowball" sampling strategy. In the early 1990s, Philip Morris, faced with increasing pressures generated both externally, from the non-smokers' rights and public health communities, and internally, from the conflicts among its varied operating companies, seriously considered leaving the tobacco business. Discussions of this option, which occurred at the highest levels of management, focused on the changing social climate regarding tobacco and smoking that the tobacco control movement had effected. However, this option was rejected in favour of the image enhancement strategy that culminated with the recent "Altria" name change. This analysis suggests that advocacy efforts have the potential to significantly denormalise tobacco as a corporate enterprise.
Ethical problems experienced by oncology nurses1
da Luz, Kely Regina; Vargas, Mara Ambrosina de Oliveira; Schmidtt, Pablo Henrique; Barlem, Edison Luiz Devos; Tomaschewski-Barlem, Jamila Geri; da Rosa, Luciana Martins
2015-01-01
Objective: to know the ethical problems experienced by oncology nurses. Method: descriptive and exploratory study with a qualitative approach, performed in inpatient units and in chemotherapy out-patients units that provide assistance to oncological patients in two capitals in the South region of Brazil. Eighteen nurses participated in this study, selected by snowball sampling type. For data collection, semi-structured interviews were carried out, which were recorded and transcribed, and then analyzed by thematic analysis. Results: two categories were established: when informing or not becomes a dilemma - showing the main difficulties related to oncological treatment information regarding health staff, health system, and infrastructure; to invest or not - dilemmas related to finitude - showing situations of dilemmas related to pain and confrontation with finitude. Conclusion: for the effective confrontation of the ethical problems experienced by oncology nurses to occur, it is important to invest in the training of these professionals, preparing them in an ethical and human way to act as lawyers of the patient with cancer, in a context of dilemmas related mainly to the possibility of finitude. PMID:26626012
Kim, Min Ah; Yi, Jaehee; Prince, Kort C; Nagelhout, Elizabeth; Wu, Yelena P
2018-01-01
This study aimed to identify young adult Korean cancer survivors' individual- (psychological distress, stigma, sociodemographic variables, and cancer-related variables) and network-level factors (relationship type, social support type) that influence discussion of their cancer experiences. Sixty-eight survivors of childhood cancer who were recruited using snowball sampling nominated 245 individuals from their networks, including family and intimate partners (40%) and friends and acquaintances (60%), as people with whom they most frequently interacted. Results of multilevel modeling analysis indicated that higher levels of internalized shame were a prominent individual-level factor associated with a lack of discussion of cancer experiences. Relationship type and support type at the network-level were also significant correlates of discussion of cancer experiences. Programs for reducing the survivors' shame, improving illness identity, and providing professional training for building social relationships that are intimate and in which they could exchange reciprocal support may help Korean childhood cancer survivors to openly share their cancer experiences with others in their social network and to be successful in the journey of cancer survivorship.
[Maternal acculturation process of married immigrant women in Korea].
Kim, Kyung Sook; Kim, Min Kyeong
2014-02-01
This study was done to explore and understand acculturation focusing on reproductive health of immigrant women. For the research sixteen immigrant women were selected by snowball sampling. Qualitative data were accumulated by in-depth interviews and private document collection. Raw data was analyzed following Mandelbaum's conceptual framework. The dimensions of immigrant women consisted of existence: emerging from the new environment in which it was hard to communicate and to get acquainted with others, reproduction: in the absence of learning and experience, reproductive health crisis, parenting: unmanageable burden. Turnings of life involved 'Inconvenience in one's eyes, vent for conflict and tension: pregnancy', 'strange medical care: accoucheur, rapid medical service', 'pain of morning sickness: poor maternal nutrition', 'manifestation of protective instinct for life'. In adaptations, content was as follows. 1) Standing alone as a Korean housewife, 2) Becoming aware of Korean maternal instinct: thirst for education supporting, 3) Rediscovery of family: growing maternal sense of existence. The results of this study show the acculturation process and the meaning of events related to reproductive health in current lives and can contribute to an integrated understanding of married immigrant women in Korean culture.
NASA Astrophysics Data System (ADS)
Koszewska, M.; Militki, J.; Mizsey, P.; Benda-Prokeinova, R.
2017-10-01
Gradual environmental degradation, shrinking of non-renewable resources, and lower quality of life are directly or indirectly arising from snowballing consumption. These unfavorable processes concern increasingly textile and clothing sector and are increasingly being felt in Visegrad Region (V4). The objective of the article was to access current consumption patterns in V4 countries, identify the factors that influence those patterns and finally to draw the conclusions for more sustainable consumption and production models as well as to make a comparative analysis of the results across V4 countries. A consumer survey was conducted to examine V4 citizens’ attitudes and behaviors in the context of sustainable consumption. To ensure sample size and comparability across countries 2000 randomly-selected V4 citizens, aged 18 and over, were interviewed. To analyze the supply side of the market and legal framework, the desk research was used. The results allowed to give some guidelines for the joint V4 strategy for solving ecological and social problems of V4 countries as well as the conclusions for textile and clothing sector.
Weekes, Carmon V N; Haas, Barbara K; Gosselin, Kevin P
2014-01-01
Despite research that suggests parental communication may help deter high-risk sexual behavior among adolescents, parents report a lack of confidence in their ability to answer sexually related questions. The purpose of this study was to test the effect of a multimedia intervention on outcome expectations and perceived self-efficacy for the sex educator role for parents of African American adolescent males. A pilot study using mixed methods was conducted. A nonprobability sample (N = 61) was obtained from a large urban community using a combination of convenience and snowball recruitment methods. Self-efficacy and outcome expectations were measured using self-reported questionnaires. A multimedia intervention for use at home and incorporating an audio CD and associated activities was implemented over a 3-week time period. Outcome expectations and self-efficacy both significantly improved after the intervention (p < .001). Findings indicate that using a multimedia approach may be effective in improving parents' outcome expectancy and self-efficacy for talking about sex with adolescent sons. © 2013 Wiley Periodicals, Inc.
Social Work’s Role in Medicaid Reform: A Qualitative Study
Wachman, Madeline; Manning, Leticia; Cohen, Alexander M.; Seifert, Robert W.; Jones, David K.; Fitzgerald, Therese; Nuzum, Rachel; Riley, Patricia
2017-01-01
Objectives. To critically analyze social work’s role in Medicaid reform. Methods. We conducted semistructured interviews with 46 stakeholders from 10 US states that use a range of Medicaid reform approaches. We identified participants using snowball and purposive sampling. We gathered data in 2016 and analyzed them using qualitative methods. Results. Multiple themes emerged: (1) social work participates in Medicaid reform through clinical practice, including care coordination and case management; (2) there is a gap between social work’s practice-level and systems-level involvement in Medicaid innovations; (3) factors hindering social work’s involvement in systems-level practice include lack of visibility, insufficient clarity on social work’s role and impact, and too few resources within professional organizations; and (4) social workers need more training in health transformation payment models and policy. Conclusions. Social workers have unique skills that are valuable to building health systems that promote population health and reduce health inequities. Although there is considerable opportunity for social work to increase its role in Medicaid reform, there is little social work involvement at the systems level. PMID:29236537
Vagenas, Panagiotis; Ludford, Kaysia T.; Gonzales, Pedro; Peinado, Jesus; Cabezas, Cesar; Gonzales, Fernando; Lama, Javier R.; Sanchez, Jorge; Altice, Frederick L.
2013-01-01
This study compared the correlates of HIV risk among men who have sex with men (MSM) with newly diagnosed versus previously known HIV infection among 5,148 MSM recruited using modified snowball sampling in 5 Peruvian cities. Participants, if age≥18 years and sex with a male in the previous 12 months, underwent standardized computer-assisted risk assessments and HIV and syphilis testing. Overall, 420 (8.2%) participants tested HIV seropositive, most of whom (89.8%) were unaware of their HIV status. Compared to those who knew themselves to be HIV-infected, multivariate logistic regression demonstrated that unprotected anal intercourse at last encounter [AOR=2.84 (95% CI 1.09–7.40)] and having an alcohol use disorder (AUD) [AOR=2.14 (95% CI 1.01–5.54)] were independently associated with a newly diagnosed HIV infection. Being unaware of being HIV-infected was associated with high-risk sexual behaviors and AUDs, both of which are amenable to behavioral and medication-assisted therapy interventions. PMID:23670711
Spineli, Vívian Marina Calixto Damasceno; Kurashima, Andrea Yamaguchi; De Gutiérrez, Maria Gaby Rivero
2015-10-01
Our aim was to describe the process of palliative sedation from the point of view of physicians and nurses working in palliative care in Brazil. Ours was a descriptive study conducted between May and December of 2011, with purposeful snowball sampling of 32 physicians and 29 nurses working in facilities in Brazil that have adopted the practice of palliative care. The symptoms prioritized for an indication of palliative sedation were dyspnea, delirium, and pain. Some 65.6% of respondents believed that the survival time of a patient in the final phase was not a determining factor for the indication of this measure, and that the patient, family, and healthcare team should participate in the decision-making process. For 42.6% of these professionals, the opinion of the family was the main barrier to an indication of this therapy. The opinion of the physicians and nurses who participated in this study converged with the principal national and international guidelines on palliative sedation. However, even though it is a therapy that has been adopted in palliative care, it remains a controversial practice.
Diagnosis Blog: Checking Up on Health Blogs in the Blogosphere
Pole, Antoinette
2010-01-01
Objectives. We analyzed the content and characteristics of influential health blogs and bloggers to provide a more thorough understanding of the health blogosphere than was previously available. Methods. We identified, through a purposive–snowball approach, 951 health blogs in 2007 and 2008. All blogs were US focused and updated regularly. We described their features, topics, perspectives, and blogger demographics. Results. Approximately half of the bloggers in our sample were employed in the health field. A majority were female, aged in their 30s, and highly educated. Two thirds posted at least weekly; one quarter accepted advertisements. Most blogs were established after 2004. They typically focused on bloggers' experiences with 1 disease or condition or on the personal experiences of health professionals. Half were written from a professional perspective, one third from a patient–consumer perspective, and a few from the perspective of an unpaid caregiver. Conclusions. Data collected from health blogs could be aggregated for large-scale empirical investigations. Future research should assess the quality of the information posted and identify what blog features and elements best reflect adherence to prevailing norms of conduct. PMID:20558802
An Exploration of Managers’ Discourses of Workplace Bullying
Johnson, Susan L.; Boutain, Doris M.; Tsai, Jenny Hsin-Chun; Beaton, Randal; de Castro, Arnold B.
2017-01-01
AIM To identify discourses used by hospital nursing unit managers to characterize workplace bullying, and their roles and responsibilities in workplace bullying management. BACKGROUND Nurses around the world have reported being the targets of bullying. These nurses often report that their managers do not effectively help them resolve the issue. There is scant research that examines this topic from the perspective of managers. METHODS This was a descriptive, qualitative study. Interviews were conducted with hospital nursing unit managers who were recruited via purposive and snowball sampling. Data were analyzed using Willig’s Foucauldian discourse analysis. RESULTS Managers characterized bullying as an interpersonal issue involving the target and the perpetrator, as an intrapersonal issue attributable to characteristics of the perpetrator, or as an ambiguous situation. For interpersonal bullying, managers described supporting target’s efforts to end bullying; for intrapersonal bullying, they described taking primary responsibility; and for ambiguous situations, they described several actions, including doing nothing. CONCLUSION Managers have different responses to different categories of bullying. Efforts need to be made to make sure they are correctly identifying and appropriately responding to incidents of workplace bullying. PMID:25597260
Manchaiah, Vinaya; Danermark, Berth; Vinay; Ahmadi, Tayebeh; Tomé, David; Krishna, Rajalakshmi; Germundsson, Per
2015-01-01
Background The current study was aimed at understanding the social representation of hearing aids in India, Iran, Portugal, and the United Kingdom. We also compared these results to explore the cross-cultural differences and similarities among these countries. Methods The study involved a cross-sectional design, and the data were collected from four different countries using the snowball sampling method. Data were analyzed using a content analysis to identify the most-similar categories of responses reported, a co-occurrences analysis to see which of these categories are reported commonly, and a chi-square analysis to study if there was any association between positive, neutral, and negative connotations among participants in different countries. Results The current study revealed four different social representations of hearing aids from India, Iran, Portugal, and the United Kingdom, and also a global index. Conclusion The study results provide very useful insights into how hearing aids are represented in the society. These findings may have important implications for public education and also for manufacturers from the viewpoint of designing and marketing hearing aids in different countries. PMID:26504376
Wong, Paul W C; Lau, Kenny C T; Liu, Lucia L; Yuen, Gloria S N; Wing-Lok, Poon
2017-06-01
It is a worldwide trend that more households are having pets or companion animals. Hence, there has been an increasing number of animal lovers experience companion animal loss bereavement. This form of bereavement has not been explored in Chinese societies. We conducted a qualitative study using in-depth interviews with 31 animal lovers and recruited through convenience and snowball sampling in Hong Kong. Companion animal loss bereavement appears to share similar features to other forms of bereavement but also has its unique features. The intensity of grief seemed to be affected by factors like the strength of the human-animal bond, lack of empathy from closed ones, being married without children, and euthanasia decision. Although the bereavement was distressful for many of our participants, many of them gradually achieved personal growth from their loss experience. We have identified seven common themes from the interview data and through self-reliance, social-supported, or professional-supported coping behaviors, people bereaved by animal loss can achieve growth from their experience. This study shows that postbereavement growth is possible from pet loss bereavement when appropriate coping strategies are adopted by the bereaved but some professional help may be needed.
Vagenas, Panagiotis; Ludford, Kaysia T; Gonzales, Pedro; Peinado, Jesus; Cabezas, Cesar; Gonzales, Fernando; Lama, Javier R; Sanchez, Jorge; Altice, Frederick L
2014-01-01
This study compared the correlates of HIV risk among men who have sex with men (MSM) with newly diagnosed versus previously known HIV infection among 5,148 MSM recruited using modified snowball sampling in 5 Peruvian cities. Participants, if age ≥18 years and reporting sex with a male in the previous 12 months, underwent standardized computer-assisted risk assessments and HIV and syphilis testing. Overall, 420 (8.2 %) participants tested HIV seropositive, most of whom (89.8 %) were unaware of their HIV status. Compared to those who knew themselves to be HIV-infected, multivariate logistic regression demonstrated that unprotected anal intercourse at last encounter [AOR = 2.84 (95 % CI 1.09-7.40)] and having an alcohol use disorder (AUD) [AOR = 2.14 (95 % CI 1.01-5.54)] were independently associated with a newly diagnosed HIV infection. Being unaware of being HIV-infected was associated with high-risk sexual behaviors and AUDs, both of which are amenable to behavioral and medication-assisted therapy interventions.
Decontamination of Water Containing Radiological Warfare Agents
1975-03-01
debris was cond~ucted undcr Project Snowball. Open tanks of water were exposed to a 500- toxi TNT explosion 2 at varying distances from grouind zero...trailhr; 4-cylinder, 4-stroke, liquid- cooled gasoline engine: aluminum evaporator-conden ser; vapor complressor; watcr pumps; heat exchanger; cngine...field consists of a 10-kw gasoline -engine-driven generator and three electric-motor-driven pumps. See Figure 21 for a photograph of the cation and anion
Early Life Crises of Habitable Planets
Pierrehumbert, Raymond
2018-05-11
There are a number of crises that a potentially habitable planet must avoid or surmount if its potential is to be realized. These include the runaway greenhouse, loss of atmosphere by chemical or physical processes, and long-lasting global glaciation. In this lecture I will present research on the climate dynamics governing such processes, with particular emphasis on the lessons to be learned from the cases of Early Mars and the Neoproterozoic Snowball Earth.
Vaisson, Gratianne; Witteman, Holly O; Bouck, Zachary; Bravo, Caroline A; Desveaux, Laura; Llovet, Diego; Presseau, Justin; Saragosa, Marianne; Taljaard, Monica; Umar, Shama; Grimshaw, Jeremy M; Tinmouth, Jill; Ivers, Noah M
2018-02-16
Cancer Care Ontario's Screening Activity Report (SAR) is an online audit and feedback tool designed to help primary care physicians in Ontario, Canada, identify patients who are overdue for cancer screening or have abnormal results requiring follow-up. Use of the SAR is associated with increased screening rates. To encourage SAR use, Cancer Care Ontario sends monthly emails to registered primary care physicians announcing that updated data are available. However, analytics reveal that 50% of email recipients do not open the email and less than 7% click the embedded link to log in to their report. The goal of the study is to determine whether rewritten emails result in increased log-ins. This manuscript describes how different user- and theory-informed messages intended to improve the impact of the monthly emails will be experimentally tested and how a process evaluation will explore why and how any effects observed were (or were not) achieved. A user-centered approach was used to rewrite the content of the monthly email, including messages operationalizing 3 behavior change techniques: anticipated regret, material incentive (behavior), and problem solving. A pragmatic, 2x2x2 factorial experiment within a multiphase optimization strategy will test the redesigned emails with an embedded qualitative process evaluation to understand how and why the emails may or may not have worked. Trial outcomes will be ascertained using routinely collected administrative data. Physicians will be recruited for semistructured interviews using convenience and snowball sampling. As of April 2017, 5576 primary care physicians across the province of Ontario, Canada, had voluntarily registered for the SAR, and in so doing, signed up to receive the monthly email updates. From May to August 2017 participants received the redesigned monthly emails with content specific to their allocated experimental condition prompting use of the SAR. We have not yet begun analyses. This study will inform how to communicate effectively with primary care providers by email and identify which behavior change techniques tested are most effective at encouraging engagement with an audit and feedback report. ClinicalTrials.gov NCT03124316; https://clinicaltrials.gov/ct2/show/NCT03124316 (Archived by WebCite at http://www.webcitation.org/6w2MqDWGu). ©Gratianne Vaisson, Holly O Witteman, Zachary Bouck, Caroline A Bravo, Laura Desveaux, Diego Llovet, Justin Presseau, Marianne Saragosa, Monica Taljaard, Shama Umar, Jeremy M Grimshaw, Jill Tinmouth, Noah M Ivers. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 16.02.2018.
NASA Astrophysics Data System (ADS)
Abbot, D. S.; Voigt, A.; Koll, D.; Pierrehumbert, R. T.
2010-12-01
We present a previously undescribed global climate state, the Jormungand state, that is nearly ice-covered with a narrow (~10-15 degrees of latitude) strip of open ocean near the equator. This state is sustained by internal dynamics of the hydrological cycle and the cryosphere. There is a new bifurcation in global climate climate associated with the Jormungand state that leads to significant hysteresis. We investigate the Jormungand state in a coupled ocean-atmosphere GCM, in multiple atmospheric GCMs coupled to a mixed layer ocean run in an idealized configuration, and we make a simple modification to the Budyko-Sellers model so that it produces Jormungand states. We suggest that the Jormungand state may be a better model for the Neoproterozoic glaciations (~635 Ma and ~715 Ma) than either the hard Snowball or the Slushball models. A Jormungand state would have a large enough region of open ocean near the equator to explain the micropaleontological and molecular clock evidence that photosynthetic eukaryotes thrived both before and immediately after the Neoproterozoic episodes. Additionally, since there is significant hysteresis associated with the Jormungand state, it can explain the cap carbonate sequences, the oxygen isotopic evidence that suggests high CO2 values, and the various evidence that suggests lifetimes for the glaciations of 1 Myrs or more. Since there is not significant hysteresis associated with the Slushball model, the Slushball model cannot explain these observations. Finally, we note that although the Slushball and Jormungand models share the characteristic of open ocean in the tropics, the Jormungand state is produced by entirely different physics, is entered through a new bifurcation in global climate, and is associated with significant hysteresis. Bifurcation diagram of global climate in the CAM global climate model, run with no continents, a 50 m mixed layer with no ocean heat transport, an eccentricity of zero, and annually and diurnally-varying insolation with a solar constant of 94% of present value. Red diamonds denote simulations initiated from ice-free conditions, blue circles denote simulations initiated from the Jormungand state, and green squares denote simulations initiated from the Snowball state. The black curve shows model equilibria, with dotted unstable solution branches (separatrices) and bifurcations drawn schematically.
Kim, Nahyun; Hughes, Tonda L; Park, Chang G; Quinn, Laurie; Kong, In Deok
2016-03-01
The purpose of this study was to compare the resting-state plasma catecholamine and anxiety levels of Korean male adolescents with Internet game addiction (IGA) and those without IGA. This cross-sectional comparative study was conducted with 230 male high school students in a South Korean city. Convenience and snowball sampling methods were employed, and data were collected using (1) participant blood samples analyzed for dopamine (DA), epinephrine (Epi), and norepinephrine (NE) and (2) two questionnaires to assess IGA and anxiety levels. Using SPSS 15.0, data were analyzed by descriptive analysis, χ(2)-tests, t-tests, and Pearson's correlation tests. The plasma Epi (t = 1.962, p < 0.050) and NE (t = 2.003, p = 0.046) levels were significantly lower in the IGA group than in the non-IGA group; DA levels did not significantly differ between the groups. The mean anxiety level of the IGA group was significantly higher compared with the non-IGA group (t = -6.193, p < 0.001). No significant correlations were found between catecholamine and anxiety levels. These results showed that excessive Internet gaming over time induced decreased peripheral Epi and NE levels, thus altering autonomic regulation, and increasing anxiety levels in male high school students. Based on these physiological and psychological effects, interventions intended to prevent and treat IGA should include stabilizing Epi, NE, and anxiety levels in adolescents.
Health care utilization in a sample of Canadian lesbian women: predictors of risk and resilience.
Bergeron, Sherry; Senn, Charlene Y
2003-01-01
This study was designed to test an exploratory path model predicting health care utilization by lesbian women. Using structural equation modeling we examined the joint influence of internalized homophobia, feminism, comfort with health care providers (HCPs), education, and disclosure of sexual identity both in one's life and to one's HCP on health care utilization. Surveys were completed by 254 Canadian lesbian women (54% participation rate) recruited through snowball sampling and specialized media. The majority (95%) of women were White, 3% (n = 7) were women of colour, and the remaining six women did not indicate ethnicity. Participants ranged in age from 18 to 67 with a mean age of 38.85 years (SD = 9.12). In the final path model, higher education predicted greater feminism, more disclosure to HCPs, and better utilization of health services. Feminism predicted both decreased levels of internalized homophobia and increased disclosure across relationships. Being more open about one's sexual identity was related to increased disclosure to HCPs, which in turn, led to better health care utilization. Finally, the more comfortable women were with their HCP the more likely they were to seek preventive care. All paths were significant at p < .01. The path model offers insight into potential target areas for intervention with the goal of improving health care utilization in lesbian women.
Marmo, Suzanne; Berkman, Cathy
2018-01-01
To address job satisfaction, and therefore employment retention, of hospice social workers, this study examined how relationships with other members of the interdisciplinary hospice team and perceptions of hospice leadership may be associated with job satisfaction of hospice social workers. The sample of 203 hospice social workers was recruited by e-mailing invitations to hospice social workers identified by hospice directors in three states, use of online social media sites accessed by hospice social workers, and snowball sampling. Study measures included professional experience, hospice characteristics, interdisciplinary collaboration, perception of servant leadership, and intrinsic and extrinsic job satisfaction. Variables significant in the model for intrinsic satisfaction were perception of servant leadership, interdisciplinary collaboration, and feeling valued by the hospice physician. Variables significant in the model for extrinsic satisfaction were perception of servant leadership, interdisciplinary collaboration, feeling valued by the hospice physician, and number of social workers at the hospice. Interdisciplinary collaboration was more important for intrinsic job satisfaction and leadership style was more important for extrinsic job satisfaction. Profit status of the hospice, experience of the social worker, caseload size, and other variables were not significant in either model. These results support previous findings that leadership style of the hospice director and relationships with hospice colleagues are important for hospice social workers' job satisfaction. Such low-cost modifications to the hospice work environment, albeit not simple, may improve job satisfaction of hospice social workers.
Mental health and polygamy: The Syrian case
Al-Krenawi, Alean
2013-01-01
AIM: To examine the psychological, self-esteem (SE), family function, marital satisfaction, life satisfaction and degree of agreement with the practice of polygamy among polygamous women with a control group from monogamous women in Syria. METHODS: Convenience sample of 136 women, 64 of whom were wives in polygamous marriages and 72 were wives in monogamous marriages participated in this study. A snowball method of sampling was used, conducted by undergraduate local female students trained to collect data according to culturally competent methods. The following research instruments were deployed: the symptoms checklist-90, the Rosenberg SE, the Life Satisfaction, family function and marital satisfaction. RESULTS: Findings revealed that women in polygamous marriages experienced lower SE, less life satisfaction, less marital satisfaction and more mental health symptomatology than women in monogamous marriages. Many of the mental health symptoms were different; noteworthy were elevated somatization, depression, hostility and psychoticism and their general severity index was higher. Furthermore, “first wife syndrome” was examined in polygamous families, comparing first with second and third wives in polygamous marriages. Findings indicated that first wives reported on more family problems, less SE, more anxiety, more paranoid ideation, and more psychoticism than second and third wives. CONCLUSION: These results are best understood through consideration of the socio-cultural and economic realities facing these women. Implications for mental health practice, policy and further research are discussed. PMID:24175180
Analysis of seaweed marketing in warbal village, Southeast Maluku Regency, Indonesia
NASA Astrophysics Data System (ADS)
Tumiwa, Bruri B.; Renjaan, Meiskyana R.; B. A Somnaikubun, Glen; Betauubun, Kamilius D.; Hungan, Marselus
2017-10-01
Seaweed in Warbal Village, West Kei Kecil Subdistrict, Southeast Maluku Regency has prospects and business opportunities are adequate to give hope to farmers in improving welfare. The fact that seaweed farming has not yet provided better and maximum results as desired by the farmers. This study aims to evaluation the marketing channels, marketing margins and profit share of marketing agencies. The research is located in Warbal Village, West Kei Kecil Subdistrict, Southeast Maluku Regency which is determined purposively. The number of sample is 30 farmers taken by simple random sampling, 2 wholesaler traders and 2 collector traders taken by using snowball method. The data collection methods is interview and questionnaire directly to farmers and marketing agencies, literary method or data collector from institutions related to the research’s aims. The research results show that there is two marketing channel, as follows: Channel I: farmers, wholesaler traders, collector traders, PAP; Channel II: farmers, collector traders, PAP. The magnitude of marketing margins is different between the marketing channels, and so it is with profit share of a marketing agency. On channel I, magnitude margin is IDR 3,250 and profit share is 71.11% on farmers, 17.76% on wholesaler traders and 11.09% on collector traders. On channel II, the magnitude of marketing margin is IDR 1,250 and profit share is 88.88% on farmers and 11.09% to collector traders.
Environmental impact on young children's participation in home-based activities.
Albrecht, Erin C; Khetani, Mary A
2017-04-01
To test the effect of child, family, and environmental factors on young children's participation in home-based activities. Caregivers of young children were recruited using convenience and snowball sampling. Participants were 395 caregivers of children (222 males, 173 females) aged from 1 month to 5 years and 11 months. Demographic items and the home section of the Young Children's Participation and Environment Measure were administered online, followed by completion of the daily activities, mobility, and social/cognitive domains of the Pediatric Evaluation of Disability Inventory Computer Adaptive Test by telephone interview. A structural equation model fitted the data well (comparative fit index=0.91) and explained 31.2% of the variance in perceived environmental support and 42.5% of the variance in home involvement. Functional limitations and performance had an indirect effect on young children's participation through their effect on perceived environmental support. Specifically, fewer functional limitations and higher task performance were associated with greater environmental support, which in turn predicted higher levels of home involvement. Results suggest the importance of a young child's functional abilities and task performance on caregiver perceptions of environmental support at home, and the impact of environmental support on a child's participation in home-based activities during the early childhood period. Results warrant replication with more diverse samples to evaluate model generalizability. © 2016 The Authors. Developmental Medicine & Child Neurology published by John Wiley & Sons Ltd on behalf of Mac Keith Press.
Pedersen, Kaspar Jessen; Boisen, Kirsten Arntz; Midtgaard, Julie; Elsbernd, Abbey; Larsen, Hanne Baekgaard
2018-03-13
An insufficient transition to normal life after cancer treatment in adolescent and young adults (AYAs) may lead to decreased occupational and educational opportunities throughout a survivor's lifespan. Key informant interviews were used to access unique knowledge of the healthcare, educational, and social systems. We used key informant interviews with professionals representing disciplines from healthcare, educational, and social systems (n = 15). Informants were recruited through purposive sampling and snowball sampling. Interviews were analyzed thematically using Malterud's Systematic Text Condensation and verified by member checking. We found four major themes: the impact of late effects, navigating the system, social reintegration, and the drive of youth. Although legal frameworks are often in place to assist AYA cancer survivors, navigating the public, educational, and social systems is a complex task and many AYAs do not have the required skill set or energy. Furthermore, AYA survivors often feel different from their peers and misunderstood by their surroundings, which may hinder reintegration into normal social life. In Scandinavia, healthcare and education are free of charge with equal access for all, primarily funded by government taxes. Therefore, insurance status and tuition fees should not constitute barriers for returning to education and work. However, this study finds that the public and educational systems are complex to navigate, and that AYAs face trouble mobilizing the energy to receive needed support.
Public Health Dental Hygienists in Massachusetts: A Qualitative Study.
Rainchuso, Lori; Salisbury, Helen
2017-06-01
Purpose: The aim of this qualitative, phenomenological study was to explore the attitudes and perceptions of public health dental hygienists on providing preventive care to underserved populations in Massachusetts. Methods: Non-probability purposive sampling was used for initial participant recruitment, and snowball sampling occurred thereafter. Data collection occurred through semi-structured interviews. Qualitative analysis was conducted using Pitney and Parker's eight-step CREATIVE process. Results: Data saturation occurred with 10 participants (n=10), one-third of the public health dental hygienists who are practicing in Massachusetts. The majority of practice settings included school-based programs (70%), while programs for children with special needs (10%) were the least common. Two major themes emerged from the data; (a) the opportunity to be an oral health change agent and (b) barriers to practice. Six subcategories emerged from the data and are reviewed within the context of their associated themes. Additionally, career satisfaction emerged as an unintended theme, and was reported as the driving force for the majority of participants. Conclusion: This study revealed a better understanding of the public health dental hygiene workforce model in Massachusetts. Public health dental hygienists in Massachusetts perceive themselves as change agents within the health care profession, and although barriers to practice are plentiful, these oral health care professionals are committed to improving access to dental care. Copyright © 2017 The American Dental Hygienists’ Association.
Pain Management and Use of Opioids in Pediatric Oncology in India: A Qualitative Approach.
Angelini, Paola; Boydell, Katherine M; Breakey, Vicky; Kurkure, Purna A; Muckaden, Marian A; Bouffet, Eric; Arora, Brijesh
2017-08-01
Consumption of medical opium for pain relief in India is low, despite the country being one of the main world producers of the substance. We investigated obstacles to opioid use and physician perceptions about optimal pain management in pediatric oncology patients in India. Semistructured interviews were conducted with oncologists who work in pediatric oncology settings. A mixed sampling strategy was used, including maximum variation and confirmation and disconfirmation of cases, as well as snowball sampling. Key informants were identified. Interviews were audio recorded, transcribed verbatim, and analyzed by thematic analysis methodology. Twenty-three interviews were performed across 20 Indian institutions. The main obstacles identified were lack of financial resources, inadequate education of health care providers on pain management, insufficient human resources (particularly lack of dedicated trained oncology nurses), poor access to opioids, and cultural perceptions about pain. Children from rural areas, treated in public hospitals, and from lower socioeconomic classes appear disadvantaged. A significant equality gap exists between public institutions and private institutions, which provide state-of-the-art treatment. The study illuminates the complexity of pain management in pediatric oncology in India, where financial constraints, lack of education, and poor access to opioids play a dominant role, but lack of awareness and cultural perceptions about pain management among health care providers and parents emerged as important contributing factors. Urgent interventions are needed to optimize care in this vulnerable population.
Snowball sampling by mail: application to a survey of smokers in the general population.
Etter, J F; Perneger, T V
2000-02-01
In a series of surveys intended for current and former smokers but sent to a random sample of the general population, we asked never smokers and smokers who did not wish to participate to transmit the questionnaire to any ever smoker they knew. We compared participants who received the questionnaire directly from us (original participants) to participants who received it from an addressee (secondary participants). Questionnaires on smoking were mailed to 3300 residents of Geneva (Switzerland) in 1997, and returned by 1167 people (35%). The final sample consisted of similar numbers of original participants (n = 578, primary response rate = 18% of total sample, or about 46% of ever smokers) and secondary participants (n = 566). Original participants were 1.7 years older than secondary participants (P = 0.03) and were more likely to be men (50% versus 43%, P = 0.009). Proportions of current smokers, stages of change, confidence in ability to quit smoking, cigarettes per day and attempts to quit smoking were similar in the two groups. Secondary participants had lower self-efficacy scores (-0.30 standard deviation (SD) units, P < 0.03), and they derived more pleasure from smoking (+0.25 SD units, P = 0.04). Among ex-smokers, direct participants were less active than secondary participants in coping with the temptation to smoke (-0.58 SD units, P = 0.002). Associations between smoking-related variables were similar in original and secondary participants. Allowing non-eligible addressees to transmit the questionnaire to someone else doubled the response rate, produced moderate bias on some variables only and had no detectable impact on associations between smoking-related variables.
NASA Technical Reports Server (NTRS)
Greenberg, J. M.
1974-01-01
The observed depletion of intermediate-weight elements O, C, and N from the interstellar medium is shown to be significantly greater than can be accounted for by accretion on interstellar dust. A number of possible explanations are presented, ranging from the existence in interstellar space of many 'snowballs' intermediate in size between dust grains and comets to the existence of many far more complicated interstellar molecules than have been detected.
Flexible climate modeling systems: Lessons from Snowball Earth, Titan and Mars
NASA Astrophysics Data System (ADS)
Pierrehumbert, R. T.
2007-12-01
Climate models are only useful to the extent that real understanding can be extracted from them. Most leading- edge problems in climate change, paleoclimate and planetary climate require a high degree of flexibility in terms of incorporating model physics -- for example in allowing methane or CO2 to be a condensible substance instead of water vapor. This puts a premium on model design that allows easy modification, and on physical parameterizations that are close to fundamentals with as little empirical ad-hoc formulation as possible. I will provide examples from two approaches to this problem we have been using at the University of Chicago. The first is the FOAM general circulation model, which is a clean single-executable Fortran-77/c code supported by auxiliary applications in Python and Java. The second is a new approach based on using Python as a shell for assembling building blocks in compiled-code into full models. Applications to Snowball Earth, Titan and Mars, as well as pedagogical uses, will be discussed. One painful lesson we have learned is that Fortran-95 is a major impediment to portability and cross-language interoperability; in this light the trend toward Fortran-95 in major modelling groups is seen as a significant step backwards. In this talk, I will focus on modeling projects employing a full representation of atmospheric fluid dynamics, rather than "intermediate complexity" models in which the associated transports are parameterized.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rose, Brian E. J.; Cronin, Timothy W.; Bitz, Cecilia M., E-mail: brose@albany.edu
Planetary obliquity determines the meridional distribution of the annual mean insolation. For obliquity exceeding 55°, the weakest insolation occurs at the equator. Stable partial snow and ice cover on such a planet would be in the form of a belt about the equator rather than polar caps. An analytical model of planetary climate is used to investigate the stability of ice caps and ice belts over the widest possible range of parameters. The model is a non-dimensional diffusive Energy Balance Model, representing insolation, heat transport, and ice−albedo feedback on a spherical planet. A complete analytical solution for any obliquity ismore » given and validated against numerical solutions of a seasonal model in the “deep-water” regime of weak seasonal ice line migration. Multiple equilibria and unstable transitions between climate states (ice-free, Snowball, or ice cap/belt) are found over wide swaths of parameter space, including a “Large Ice-Belt Instability” and “Small Ice-Belt Instability” at high obliquity. The Snowball catastrophe is avoided at weak radiative forcing in two different scenarios: weak albedo feedback and inefficient heat transport (favoring stable partial ice cover), or efficient transport at high obliquity (favoring ice-free conditions). From speculative assumptions about distributions of planetary parameters, three-fourths to four-fifths of all planets with stable partial ice cover should be in the form of Earth-like polar caps.« less
Social connectedness and mobile phone use among refugee women in Australia.
Walker, Rae; Koh, Lee; Wollersheim, Dennis; Liamputtong, Pranee
2015-05-01
The aim of this research was to inform the development of mobile phone-assisted health promotion programmes that support social connectedness among refuge women to enhance their mental, physical and social health. For refugees, relationship development during the early stages of resettlement is often difficult. Enhancing personal skills, and resources, can enhance relationships that provide social support. It can also contribute to the development of social relationships in communities and thence acculturation. Communication technologies can assist refugees, if their particular needs and capacities are taken into account. This paper reports a study of refugee women's experience of an intervention based on principles of empowerment and using peer support training and the provision of free mobile phones, and free calls, for at least 1 year. Potential participants were invited by the Afghan, Burmese and Sudanese community leaders to an information session, where the study was explained and invitations to participate extended. A snowball sampling technique was also used, where the first group of participants invited people they had relationships with to join the programme. One hundred and eleven participants were recruited from the three groups. All were from refugee backgrounds. Data collection consisted of: a pre- and post-intervention questionnaire; a log of outgoing phone calls; and in-depth interviews with a subgroup of the study population. The call logs described the patterns of interpersonal relationships facilitated by the mobile phones. In the interviews, characteristics of interpersonal social support, and relationships with heritage and host communities, were described. The quantitative data were analysed using descriptive statistics and the qualitative data using thematic analysis. By describing the conditions under which mobile phone technology can enhance interpersonal and community connectedness, we strengthen the evidence base for the use of mobile phone technology in health promotion programmes with refugee groups. © 2014 John Wiley & Sons Ltd.
A qualitative study of emergency physicians' perspectives on PROMS in the emergency department.
Dainty, Katie N; Seaton, Bianca; Laupacis, Andreas; Schull, Michael; Vaillancourt, Samuel
2017-09-01
There is a growing emphasis on including patients' perspectives on outcomes as a measure of quality care. To date, this has been challenging in the emergency department (ED) setting. To better understand the root of this challenge, we looked to ED physicians' perspectives on their role, relationships and responsibilities to inform future development and implementation of patient-reported outcome measures (PROMs). ED physicians from hospitals across Canada were invited to participate in interviews using a snowballing sampling technique. Semistructured interviews were conducted by phone with questions focused on the role and practice of ED physicians, their relationship with their patients and their thoughts on patient-reported feedback as a mechanism for quality improvement. Transcripts were analysed using a modified constant comparative method and interpretive descriptive framework. Interviews were completed with 30 individual physicians. Respondents were diverse in location, training and years in practice. Physicians reported being interested in 'objective' postdischarge information including adverse events, readmissions, other physicians' notes, etc in a select group of complex patients, but saw 'patient-reported' feedback as less valuable due to perceived biases. They were unsure about the impact of such feedback mainly because of the episodic nature of their work. Concerns about timing, as well as about their legal and ethical responsibilities to follow-up if poor patient outcomes are reported, were raised. Data collection and feedback are key elements of a learning health system. While patient-reported outcomes may have a role in feedback, ED physicians are conflicted about the actionability of such data and ethical implications, given the inherently episodic nature of their work. These findings have important implications for PROM design and implementation in this unique clinical setting. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Lionis, Christos; Papadakaki, Maria; Saridaki, Aristoula; Dowrick, Christopher; O'Donnell, Catherine A; Mair, Frances S; van den Muijsenbergh, Maria; Burns, Nicola; de Brún, Tomas; O'Reilly de Brún, Mary; van Weel-Baumgarten, Evelyn; Spiegel, Wolfgang; MacFarlane, Anne
2016-01-01
Objectives Guidelines and training initiatives (G/TIs) are available to support communication in cross-cultural consultations but are rarely implemented in routine practice in primary care. As part of the European Union RESTORE project, our objective was to explore whether the available G/TIs make sense to migrants and other key stakeholders and whether they could collectively choose G/TIs and engage in their implementation in primary care settings. Setting As part of a comparative analysis of 5 linked qualitative case studies, we used purposeful and snowball sampling to recruit migrants and other key stakeholders in primary care settings in Austria, England, Greece, Ireland and the Netherlands. Participants A total of 78 stakeholders participated in the study (Austria 15, England 9, Ireland 11, Greece 16, Netherlands 27), covering a range of groups (migrants, general practitioners, nurses, administrative staff, interpreters, health service planners). Primary and secondary outcome measures We combined Normalisation Process Theory (NPT) and Participatory Learning and Action (PLA) research to conduct a series of PLA style focus groups. Using a standardised protocol, stakeholders' discussions about a set of G/TIs were recorded on PLA commentary charts and their selection process was recorded through a PLA direct-ranking technique. We performed inductive and deductive thematic analysis to investigate sensemaking and engagement with the G/TIs. Results The need for new ways of working was strongly endorsed by most stakeholders. Stakeholders considered that they were the right people to drive the work forward and were keen to enrol others to support the implementation work. This was evidenced by the democratic selection by stakeholders in each setting of one G/TI as a local implementation project. Conclusions This theoretically informed participatory approach used across 5 countries with diverse healthcare systems could be used in other settings to establish positive conditions for the start of implementation journeys for G/TIs to improve healthcare for migrants. PMID:27449890
Arrey, Agnes Ebotabe; Bilsen, Johan; Lacor, Patrick; Deschepper, Reginald
2016-01-01
Spirituality/religion serves important roles in coping, survival and maintaining overall wellbeing within African cultures and communities, especially when diagnosed with a chronic disease like HIV/AIDS that can have a profound effect on physical and mental health. However, spirituality/religion can be problematic to some patients and cause caregiving difficulties. The objective of this paper was to examine the role of spirituality/religion as a source of strength, resilience and wellbeing among sub-Saharan African (SSA) migrant women with HIV/AIDS. A qualitative study of SSA migrant women was conducted between April 2013 and December 2014. Participants were recruited through purposive sampling and snowball techniques from AIDS Reference Centres and AIDS workshops in Belgium, if they were 18 years and older, French or English speaking, and diagnosed HIV positive more than 3 months beforehand. We conducted semi-structured interviews with patients and did observations during consultations and support groups attendances. Thematic analysis was used to analyse the data. 44 women were interviewed, of whom 42 were Christians and 2 Muslims. None reported religious/spiritual alienation, though at some point in time many had felt the need to question their relationship with God by asking “why me?” A majority reported being more spiritual/religious since being diagnosed HIV positive. Participants believed that prayer, meditation, regular church services and religious activities were the main spiritual/religious resources for achieving connectedness with God. They strongly believed in the power of God in their HIV/AIDS treatment and wellbeing. Spiritual/religious resources including prayer, meditation, church services, religious activities and believing in the power of God helped them cope with HIV/AIDS. These findings highlight the importance of spirituality in physical and mental health and wellbeing among SSA women with HIV/AIDS that should be taken into consideration in providing a caring and healthy environment. PMID:27447487
Exploring Australian Aboriginal Women’s experiences of menopause: a descriptive study
2014-01-01
Background Despite extensive literature demonstrating differing experiences in menopause around the world, documentation of the experience of menopause in Australian Aboriginal women is scarce, and thus their menopausal experience is relatively unknown. This study aimed to understand Australian Aboriginal women’s understanding and experience of menopause and its impact on their lives. Methods The study was an exploratory qualitative study. Twenty-five Aboriginal women were recruited from a regional centre in the Mid-West region of Western Australia using opportunistic and snowballing sampling. Interviews and focus group discussions were undertaken from February 2011 to February 2012 using open-ended questioning with a yarning technique. Thematic analysis was undertaken of the transcribed interviews. Results A number of themes were revealed. These related to the language used, meanings and attitudes to menopause, symptoms experienced, the role of men, a lack of understanding, coping mechanisms and the attribution of menopausal changes to something else. The term “change of life” was more widely recognised and signified the process of ageing, and an associated gain of respect in the local community. A fear of menopausal symptoms or uncertainty about their origin was also common. Overall, many women reported insufficient understanding and a lack of available information to assist them and their family to understand the transition. Conclusion There are similarities between Aboriginal and non-Aboriginal experiences of menopause, including similar symptom profiles. The current language used within mainstream health settings may not be appropriate to this population if it fails to recognise the importance of language and reflect the attributed meaning of menopause. The fear of symptoms and uncertainty of their relationship to menopause demonstrated a need for more information which has not adequately been supplied to Australian Aboriginal women through current services. While this study is with a select population of Aboriginal Australian women, it reveals the importance of acknowledging differences, particularly in use of language to convey ideas and support Aboriginal women experiencing menopause. PMID:24646300
Barriers to HIV testing among male clients of female sex workers in Indonesia.
Fauk, Nelsensius Klau; Sukmawati, Anastasia Suci; Berek, Pius Almindu Leki; Ernawati; Kristanti, Elisabeth; Wardojo, Sri Sunaringsih Ika; Cahaya, Isaias Budi; Mwanri, Lillian
2018-05-30
Frequent engagement of men in sexual encounters with female sex workers (FSWs) without using condoms places them at a high risk for HIV infection. HIV testing has been noted to be among important strategies to prevent HIV transmission and acquisition. However, it is known that not all men willingly undertake an HIV test as a way to prevent HIV transmission and/or acquisition. This study aimed to identify barriers to accessing HIV testing services among men who are clients of FSWs (clients) in Belu and Malaka districts, Indonesia. A qualitative inquiry employing face to face open ended interviews was conducted from January to April 2017. The participants (n = 42) were clients of FSWs recruited using purposive and snowball sampling techniques. Data were analysed using a qualitative data analysis framework. Findings indicated three main barriers of accessing HIV testing services by clients. These included: (1) personal barriers (lack of knowledge of HIV/AIDS and HIV testing availability, and unwillingness to undergo HIV testing due to low self-perceived risk of HIV and fear of the test result); (2) health care service provision barriers (lack of trust in health professionals and limited availability of medication including antiretroviral (ARV)); and (3) social barriers (stigma and discrimination, and the lack of social supports). These findings indicated multilevelled barriers to accessing HIV testing services among participants, who are known to be among key population groups in HIV care. Actions to improve HIV/AIDS-related health services accessibility are required. The dissemination of the knowledge and information on HIV/AIDS and improved available of HIV/AIDS-related services are necessary actions to improve the personal levelled barriers. System wide barriers will need improved practices and health policies to provide patients friendly and accessible services. The societal levelled barriers will need a more broad societal approach including raising awareness in the community and enhanced discussions about HIV/AIDS issues in order to normalise HIV in the society.
Lorente, Nicolas; Henry, Emilie; Fugon, Lionel; Yomb, Yves; Carrieri, Maria Patrizia; Eboko, Fred; Spire, Bruno
2012-01-01
In low- and middle-income countries, men who have sex with men (MSM) are 19 times more likely to be HIV positive compared with background populations. Criminalisation and social rejection of homosexuality in most sub-Saharan African countries reinforce stigma and exclude MSM from prevention activities, including HIV testing. This paper's purpose is to identify factors associated with never having been HIV tested (NHT), among a sample of Cameroonian MSM. In 2008, a community-based study was conducted in Douala, the economic capital city of Cameroon, by a local NGO Alternatives-Cameroun, recruiting participants through the snowball technique and administering a questionnaire during face-to-face interviews. Proximity to HIV was investigated according to the following criteria: knowing at least one person living with HIV and having been exposed to HIV prevention interventions. NHT was defined as reporting to have never been HIV tested. A logistic regression was used to identify factors associated with NHT. Among the 165 MSM of our study group who reported that they were not HIV positive, 19% reported NHT. Factors independently associated with NHT were as follows: being younger, being Muslim, not having a steady male partner, not knowing any person living with HIV and never having been exposed to HIV prevention interventions. In this MSM population, a small proportion reported that they had never been HIV tested and among these, the percentage was higher among individuals not in proximity to HIV. Despite the hostile context of sub-Saharan African countries towards MSM, local and national HIV testing campaigns to date may have played a substantial role in raising HIV awareness in the MSM population living in Douala, and peer-based counselling may have educated those in contact with Alternatives-Cameroun regarding the positive value of HIV testing. This result is a further argument for continuing community-based prevention and extending it to difficult-to-reach MSM.
Fujita, Noriko; Abe, Kimiko; Rotem, Arie; Tung, Rathavy; Keat, Phuong; Robins, Ann; Zwi, Anthony B
2013-01-01
Objective To identify factors that have contributed to the systematic development of the Cambodian human resources for health (HRH) system with a focus on midwifery services in response to high maternal mortality in fragile resource-constrained countries. Design Qualitative case study. Review of the published and grey literature and in-depth interviews with key informants and stakeholders using an HRH system conceptual framework developed by the authors (‘House Model’; Fujita et al, 2011). Interviews focused on the perceptions of respondents regarding their contributions to strengthening midwifery services and the other external influences which may have influenced the HRH system and reduction in the maternal mortality ratio (MMR). Setting Three rounds of interviews were conducted with senior and mid-level managers of the Ministries of Health (MoH) and Education, educational institutes and development partners. Participants A total of 49 interviewees, who were identified through a snowball sampling technique. Main outcome measures Scaling up the availability of 24 h maternal health services at all health centres contributing to MMR reduction. Results The incremental development of the Cambodian HRH system since 2005 focused on the production, deployment and retention of midwives in rural areas as part of a systematic strategy to reduce maternal mortality. The improved availability and access to midwifery services contributed to significant MMR reduction. Other contributing factors included improved mechanisms for decision-making and implementation; political commitment backed up with necessary resources; leadership from the top along with a growing capacity of mid-level managers; increased MoH capacity to plan and coordinate; and supportive development partners in the context of a conducive external environment. Conclusions Lessons from this case study point to the importance of a systemic and comprehensive approach to health and HRH system strengthening and of ongoing capacity enhancement and leadership development to ensure effective planning, implementation and monitoring of HRH policies and strategies. PMID:23674446
Drennan, Vari M; Porter, Elizabeth M J; Grant, Robert L
2013-08-01
Educationalists and managers internationally are challenged to find ways of preparing, recruiting early in their careers, and retaining nurses into public health roles in primary care. Public health nursing qualifications are post-initial nurse registration in the United Kingdom as in some other countries. In the mid twentieth century there were a number of innovative programmes of dual qualification: registered nurse and health visitor (the United Kingdom term for public health nurse). To investigate the career histories of graduates from courses integrating both nursing and health visitor qualifications. An observational, survey study. The United Kingdom. A purposive sample of graduates from integrated registered nurse and health visitor programmes, 1959-1995, from one University. Self completed, anonymous, survey sent to graduates, with contact details known to the University and through snowballing techniques, in 2011. Forty five women (56%), graduates in all four decades, returned the survey. A significant majority (82%) had taken up health visitor posts on completing the course. Over their careers, 42% of all jobs held were as health visitors. Only four never worked in a post that required a health visiting qualification. Most had undertaken paid work throughout their careers that focused on aspects of public health, often linked to child, maternal and/or family wellbeing. Many held teaching/lecturing and management posts at some point in their career. Those holding management posts were more likely to report leaving them as a result of organisational re-structuring or redundancy than those in non-management posts. Courses that prepare students to be both nurses and health visitors result in a majority of graduates who take up posts as health visitors on qualification and subsequently. Nurse education planners may find this evidence of value in determining ways of providing a future workforce for public health nursing. Copyright © 2012 Elsevier Ltd. All rights reserved.
Lauder, Bonnie; Sinclair, Peter M; Maguire, Jane
2018-04-01
This study aimed to identify and describe the experience of parents of children diagnosed with early onset scoliosis living in Australia. Chronic childhood disease has a major impact on health-related quality of life. Caring for a child with a chronic illness is well documented but the specific experiences of parents who care for children with early onset scoliosis, a rare but devastating illness, has not been explored. Numerous studies have described the interrelated psychological, financial, social, physical and logistical factors that impact the experience of the caregiver role with various diseases, but in the case of early onset scoliosis, limited studies have been conducted about the parental experience. A qualitative descriptive design was used. A snowball sampling technique assisted in the recruitment. Parents invited to the study included mothers, fathers and guardians. Data were collected through semistructured interviews and transcribed verbatim. Transcripts were analysed thematically. Data collection complied with the Consolidated criteria for reporting qualitative research guidelines. Twelve mothers of children with early onset scoliosis were interviewed, as only mothers consented to participate. Four major themes emerged: emotional rollercoaster ride, a lack of resources, money talks and pervasive burden. Factors that impacted on the participants' ability to confront, manage and endure caring for a child with early onset scoliosis emerged from the data. The findings suggest there are multiple factors that influence the experience of mothers' caring for a child with early onset scoliosis. The recognition and appropriate management of these factors by healthcare professionals have the potential to improve the quality of life of parents who care for a child with early onset scoliosis. Healthcare professionals have first-line contact with parents of children with early onset scoliosis and are well placed to provide parents with evidence-based education and increased support. © 2018 John Wiley & Sons Ltd.
Mazerolle, Stephanie M.; Borland, John F.; Burton, Laura J.
2012-01-01
Context Female athletic trainers (ATs) experience gender discrimination in the workplace due to stereotypical gender roles, but limited information is available regarding the topic. Objective To understand the challenges and obstacles faced by young female ATs working in National Collegiate Athletic Association Division I athletics. Design Exploratory study using semistructured interviews. Setting Division I clinical setting. Patients or Other Participants A total of 14 female ATs were included in the study, using both criterion and snowball- sampling techniques. Their mean age was 27 ± 2 years, with 5 ± 2 years of overall clinical experience. Criteria included employment at the Division I clinical setting, being a full-time assistant AT, and at least 3 years of working experience but no more than 9 years to avoid role continuance. Data Collection and Analysis Analysis of the interview data followed inductive procedures as outlined by a grounded theory approach. Credibility was established by member checks, multiple-analyst triangulation, and peer review. Results Clear communication with both coaches and players about expectations and philosophies regarding medical care, a supportive head AT in terms of clinical competence, and having and serving as a role model were cited as critical tools to alleviate gender bias in the workplace. Conclusions The female ATs in this study stressed the importance of being assertive with coaches early in the season with regard to the AT's role on the team. They reasoned that these actions brought forth a greater perception of congruity between their roles as ATs and their gender and age. We suggest that female athletic training students seek mentors in their field while they complete their coursework and practicums. The ATs in the current study indicated that a mentor, regardless of sex, helped them feel empowered to navigate the male-centric terrain of athletic departments by encouraging them to be assertive and not second-guess their decisions. PMID:23182018
Svavarsdóttir, Margrét Hrönn; Sigurðardóttir, Árún K; Steinsbekk, Aslak
2015-05-13
Health professionals with the level of competency necessary to provide high-quality patient education are central to meeting patients' needs. However, research on how competencies in patient education should be developed and health professionals trained in them, is lacking. The aim of this study was to investigate the characteristics of an expert educator according to health professionals experienced in patient education for patients with coronary heart disease, and their views on how to become an expert educator. This descriptive qualitative study was conducted through individual interviews with health professionals experienced in patient education in cardiac care. Participants were recruited from cardiac care units and by using a snowball sampling technique. The interviews were audiotaped and transcribed verbatim. The data were analyzed with thematic approaches, using systematic text condensation. Nineteen Icelandic and Norwegian registered nurses, physiotherapists, and cardiologists, who had worked in cardiac care for 12 years on average, participated in the study. Being sensitive to the patient's interests and learning needs, and possessing the ability to tailor the education to each patient's needs and context of the situation was described as the hallmarks of an expert educator. To become an expert educator, motivation and active participation of the novice educator and a supportive learning environment were considered prerequisites. Supportive educational resources, observation and experiential training, and guidance from experienced educators were given as examples of resources that enhance competence development. Experienced educators expressed the need for peer support, inter-professional cooperation, and mentoring to further develop their competency. Expert patient educators were described as those demonstrating sensitivity toward the patient's learning needs and an ability to individualize the patient's education. A supportive learning environment, inner motivation, and an awareness of the value of patient education were considered the main factors required to become an expert educator. The experienced educators expressed a need for continuing education and peer support.
Choonara, S; Goudge, J; Nxumalo, N; Eyles, J
2017-01-01
Background The district health system (DHS) has a critical role to play in the delivery of primary healthcare (PHC). Effective district management, particularly leadership is considered to be crucial element of the DHS. Internationally, the debate around developing leadership competencies such as motivation or empowerment of staff, managing relationships, being solution driven as well as fostering teamwork are argued to be possible through approaches such as formal and informal training. Despite growing multidisciplinary evidence in fields such as engineering, computer sciences and health sciences there remains little empirical evidence of these approaches, especially the informal approach. Findings are based on a broader doctoral thesis which explored district financial management; although the core focus of this paper draws attention to the significance of informal learning and its practical value in developing leadership competencies. Methods A qualitative case study was conducted in one district in the Gauteng province, South Africa. Purposive and snowballing techniques yielded a sample of 18 participants, primarily based at a district level. Primary data collected through in-depth interviews and observations (participant and non-participant) were analysed using thematic analysis. Findings Results indicate the sorts of complexities, particularly financial management challenges which staff face and draws attention to the use of two informal learning strategies—learning from others (how to communicate, delegate) and fostering team-based learning. Such strategies played a role in developing a cadre of leaders at a district level who displayed essential competencies such as motivating staff, and problem solving. Conclusions It is crucial for health systems, especially those in financially constrained settings to find cost-effective ways to develop leadership competencies such as being solution driven or motivating and empowering staff. This study illustrates that it is possible to develop such competencies through creating and nurturing a learning environment (on-the-job training) which could be incorporated into everyday practice. PMID:28588998
Gyesaw, Nana Yaa Konadu; Ankomah, Augustine
2013-01-01
Background The proportion of teenage girls who are mothers or who are currently pregnant in sub-Saharan African countries is staggering. There are many studies regarding teenage pregnancy, unsafe abortions, and family planning among teenagers, but very little is known about what happens after pregnancy, ie, the experience of teenage motherhood. Several studies in Ghana have identified the determinants of early sexual activity, contraception, and unsafe abortion, with teenage motherhood only mentioned in passing. Few studies have explored the experiences of adolescent mothers in detail with regard to their pregnancy and childbirth. This qualitative study explores the experiences of adolescent mothers during pregnancy, childbirth, and care of their newborns. Methods This qualitative study was based on data from focus group discussions and indepth interviews with teenage mothers in a suburb in Accra. Participants were recruited from health facilities as well as by snowball sampling. Results Some of the participants became pregnant as a result of transactional sex in order to meet their basic needs, while others became pregnant as a result of sexual violence and exploitation. A few others wanted to become pregnant to command respect from people in society. In nearly all cases, parents and guardians of the adolescent mothers were upset in the initial stages when they heard the news of the pregnancy. One key finding, quite different from in other societies, was how often teenage pregnancies are eventually accepted, by both the young women and their families. Also observed was a rarity of willingness to resort to induced abortion. Conclusion Special programs should be initiated by the government and the various responsible departments to address ignorance on sexual matters, and the challenges and risks associated with pregnancy and parenting by adolescents. Parenting techniques should be taught in sex education programs. PMID:24250233
Choonara, S; Goudge, J; Nxumalo, N; Eyles, J
2017-01-01
The district health system (DHS) has a critical role to play in the delivery of primary healthcare (PHC). Effective district management, particularly leadership is considered to be crucial element of the DHS. Internationally, the debate around developing leadership competencies such as motivation or empowerment of staff, managing relationships, being solution driven as well as fostering teamwork are argued to be possible through approaches such as formal and informal training. Despite growing multidisciplinary evidence in fields such as engineering, computer sciences and health sciences there remains little empirical evidence of these approaches, especially the informal approach. Findings are based on a broader doctoral thesis which explored district financial management; although the core focus of this paper draws attention to the significance of informal learning and its practical value in developing leadership competencies. A qualitative case study was conducted in one district in the Gauteng province, South Africa. Purposive and snowballing techniques yielded a sample of 18 participants, primarily based at a district level. Primary data collected through in-depth interviews and observations (participant and non-participant) were analysed using thematic analysis. Results indicate the sorts of complexities, particularly financial management challenges which staff face and draws attention to the use of two informal learning strategies-learning from others (how to communicate, delegate) and fostering team-based learning. Such strategies played a role in developing a cadre of leaders at a district level who displayed essential competencies such as motivating staff, and problem solving. It is crucial for health systems, especially those in financially constrained settings to find cost-effective ways to develop leadership competencies such as being solution driven or motivating and empowering staff. This study illustrates that it is possible to develop such competencies through creating and nurturing a learning environment (on-the-job training) which could be incorporated into everyday practice.