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
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.
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.
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.
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.
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.
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
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.
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.
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
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.
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
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.
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
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.
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…
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…
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…
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.
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…
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…
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.
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…
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…
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.…
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…
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
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…
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
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.…
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…
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.
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
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)…
"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…
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
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.
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.
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.
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.
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.
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
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.
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.
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 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.
[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.
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.
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.
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.
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.
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
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.
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…
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.
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…
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…
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.
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.
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.
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…
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.
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…
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.
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.
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.
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.
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.
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.
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…
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…
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.
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.
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
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.
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…
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…
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.
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.
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.
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.
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.
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.
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…
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…
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…
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.
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.
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
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.
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.
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…
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…
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.
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)
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.
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
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…
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.
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
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)
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).
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.
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.
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…
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.
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.
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.
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.
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
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
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.
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
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.
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.
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.
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
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.
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
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].
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.
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
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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
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
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
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.
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.
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.
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.
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.
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
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.
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.
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.
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.
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.
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.
Iravani, Mina; Janghorbani, Mohsen; Zarean, Ellahe; Bahrami, Masod
2016-01-01
Background: 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. Objectives: 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. Materials and Methods: 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. Results: 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. Conclusions: 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. PMID:27175303
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.
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.
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.
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.
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.
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
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.
What are the people's attitudes toward spinal cord injury victims (from common to elite)
Hosseinigolafshani, Zahra; Abedi, Heidarali; Ahmadi, Fazlolah
2014-01-01
Background: One of the acutely fatal and prevalent crises in all societies is acute spinal cord injury. Individuals with a spinal cord injury are prone to numerous challenges, perturbation, and acute mental distresses. One of their concerns, often expressed generally and in the form of a complaint, is how people deal with them. The present study aims to analyze the experiences and interactions of the disabled with the society and to achieve a deep clarification of their internal attitudes and realistic approaches in various social classes (from common people to elite). Materials and Methods: The present study is a part of a greater research with a classical grounded theory approach conducted on 12 successful and nationally and internationally popular disabled people. Sampling was firstly purposive and then continued with snowball sampling. The data were collected by open deep interviews which were recorded and transcribed verbatim. The obtained data were analyzed by Graneheim content analysis method. Results: The findings obtained through analysis of the interviews yielded the theme of a socially suppressing attitude which contained four subthemes of compassionate attitude, disability attitude, inhuman attitude, and atonement attitude. Conclusions: The results showed that both groups of common, and educated and elite classes of Iranian society have identically suppressing attitudes and interactions toward spinal cord injury victims. It seems that traditional attitudes yet preponderate academic and scientific knowledge in Iranian society. This gap needs notable attention of all the Iranians, especially policy makers and social personalities. PMID:24949065
Health Information Management System for Elderly Health Sector: A Qualitative Study in Iran
Sadoughi, Farahnaz; Shahi, Mehraban; Ahmadi, Maryam; Davaridolatabadi, Nasrin
2016-01-01
Background: There are increasing change and development of information in healthcare systems. Given the increase in aging population, managers are in need of true and timely information when making decision. Objectives: The aim of this study was to investigate the current status of the health information management system for the elderly health sector in Iran. Materials and Methods: This qualitative study was conducted in two steps. In the first step, required documents for administrative managers were collected using the data gathering form and observed and reviewed by the researcher. In the second step, using an interview guide, the required information was gathered through interviewing experts and faculty members. The convenience, purposeful and snowball sampling methods were applied to select interviewees and the sampling continued until reaching the data saturation point. Finally, notes and interviews were transcribed and content analysis was used to analyze them. Results: The results of the study showed that there was a health information management system for the elderly health sector in Iran. However, in all primary health care centers the documentation of data was done manually; the data flow was not automated; and the analysis and reporting of data are also manually. Eventually, decision makers are provided with delayed information. Conclusions: It is suggested that the steward of health in Iran, the ministry of health, develops an appropriate infrastructure and finally puts a high priority on the implementation of the health information management system for elderly health sector in Iran. PMID:27186383
Medicinal plants used in the treatment of diabetes in karo ethnic, north sumatra, indonesia
NASA Astrophysics Data System (ADS)
Raja Nasution, Barita; Alief Aththorick, T.; Rahayu, Suci
2018-03-01
Medicinal plants derived from traditional medicines have played an important role in managing a variety of healthcare and diseases in Karo ethnic in North Sumatra, Indonesia. The study aimed to document the ethnobotanical information on medicinal plants used by traditional healers of Karo ethnic in the treatment of diabetes and to assess the crude extract of phytochemical constituents qualitatively from medicinal plant organ. The study was conducted on two Karo sub-ethnic living at the highland (Karo Gugung) in Karo Regency and the lowland (Karo Jahe) in Langkat Regency with the length of the study was eight months of observation. The survey was conducted using open-ended interviews among four traditional healers those who were selected by snowball sampling method; quantitative analysis of ethnobotanical data was performed by calculating the familiarity index (Fi). Fresh plant samples which were used for phytochemical analysis were collected using participatory method. The results showed that 15 plants were used to treat diabetes by Karo traditional healers. The plants are Blumea balsamifera, Nypa fruticans, Bischofia javanica, Eleutherine americana, Allium cepa, A. sativum, Eugenia polyantha, Piper betle, P. nigrum, Citrus aurantiifolia, Boesenbergia pandurata, Curcuma longa, Kaempferia galanga, Zingiber montanum, and Z. officinale. Familiarity index (Fi) value of each plant was 25 which explained that each of medicinal plant was used by only one traditional healer. The phytochemical screening showed that the crude plant extracts contained phenolic, terpenoid, steroid, and saponin.
Challenges and Opportunities in the Provision of Surgical Care in Vanuatu: A Mixed Methods Analysis.
Young, S; Perry, W R G; Leodoro, B; Nosa, V; Bissett, I; Windsor, J A; Dare, A J
2016-08-01
The Pacific island nation of Vanuatu faces a number of challenges in delivering surgical care to its population. We aimed to understand and document the barriers, opportunities and required actions to improve surgical care in the country using a mixed methods analysis which incorporated the perspectives of local health stakeholders. A baseline quantitative assessment of surgical capacity in Vanuatu was carried out using the WHO situational analysis tool. Twenty semi-structured interviews were then conducted on the two main islands (Efate and Espiritu Santo) with surgeons, allied health staff, health managers, policy-makers and other key stakeholders, using a grounded theory qualitative case study methodology. Initial informants were identified by purposive sampling followed by snowball sampling until theoretical saturation was reached. Interviews were open and axially coded with subsequent thematic analysis. Vanuatu faces deficits in surgical infrastructure, equipment and human resources, especially in the rural provinces. Geographic isolation, poverty and culture-including the use of traditional medicine and low health literacy-all act as barriers to patients accessing timely surgical care. Issues with governance, human resourcing and perioperative care were commonly identified by stakeholders as key challenges facing surgical services. Increasing outreach clinics, developing efficient referral systems, building provincial surgical capacity and undertaking locally led research were identified as key actions that can improve surgical care. Documenting locally identified challenges and opportunities for surgical care in Vanuatu is an important first step towards developing formal strategies for improving surgical services at the country level.
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.
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.
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.
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.
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
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
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
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.
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
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).
Chhim, Srean; Macom, John; Pav, Chettana; Nim, Nirada; Yun, Phearun; Seng, Sopheap; Chhim, Kolab; Tuot, Sovannary; Yi, Siyan
2017-10-18
Early HIV diagnosis and initiation onto antiretroviral therapy may prevent ongoing spread of HIV. Risk Tracing Snowball Approach (RTSA) has been shown to be effective in detecting new HIV cases in other settings. The main objective of this study is to evaluate the effectiveness of RTSA in increasing the rate of newly identified HIV cases among high-risk populations. Our second objective was to evaluate the effectiveness of RTSA, as compared to the walk-in group, in increasing the number of HIV tests and early case detection. This study was conducted from April 1 to September 30, 2016 at two NGO clinics in Phnom Penh, Cambodia. Respondent driven sampling method was adapted to develop RTSA to reach high-risk populations, including key populations and the general population who have social connections with key populations. Bivariate and multivariate logistic regression analyses were conducted. During the implementation period, 721 clients walked in for HIV testing (walk-in group), and all were invited to be seeds. Of the invited clients, 36.6% agreed to serve as seeds. Throughout the implementation, 6195 coupons were distributed to seeds or recruiters, and resulted in 1572 clients visiting the two clinics with coupons (RTSA group), for a coupon return rate of 25.3%. The rate of newly identified HIV cases among the RTSA group was significantly lower compared to that in walk-in group. However, the highest number of newly identified HIV cases was found during the implementation period, compared to both pre- and post-implementation period. Although statistically not significant, the mean CD4 count of newly identified HIV cases detected through RTSA was almost 200 cells/mm3 higher than that in the walk-in group. Although the rate of newly identified HIV cases among the RTSA group was lower than that in the walk-in group, the inclusion of RTSA in addition to the traditional walk-in method boosted new HIV case detection in the two participating clinics. A higher mean CD4 count for the RTSA group may reveal that RTSA may be able to detect HIV cases earlier than the traditional walk-in approach. Further research is needed to understand whether RTSA is a cost-effective intervention to prevent ongoing spread of the HIV among high-risk populations in Cambodia.
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.
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.
Relapse Model among Iranian Drug Users: A Qualitative Study.
Jalali, Amir; Seyedfatemi, Naiemeh; Peyrovi, Hamid
2015-01-01
Relapse is a common problem in drug user's rehabilitation program and reported in all over the country. An in-depth study on patients' experiences can be used for exploring the relapse process among drug users. Therefore, this study suggests a model for relapse process among Iranian drug users. In this qualitative study with grounded theory approach, 22 participants with rich information about the phenomenon under the study were selected using purposive, snowball and theoretical sampling methods. After obtaining the informed consent, data were collected based on face-to-face, in-depth, semi-structured interviews. All interviews were analyzed in three stages of axial, selective and open coding methods. Nine main categories emerged, including avoiding of drugs, concerns about being accepted, family atmosphere, social conditions, mental challenge, self-management, self-deception, use and remorse and a main category, feeling of loss as the core variable. Mental challenge has two subcategories, evoking pleasure and craving. Relapse model is a dynamic and systematic process including from cycles of drug avoidance to remorse with a core variable as feeling of loss. Relapse process is a dynamic and systematic process that needs an effective control. Determining a relapse model as a clear process could be helpful in clinical sessions. RESULTS of this research have depicted relapse process among Iranian drugs user by conceptual model.
Parents' Voice in Managing the Pain of Children with Cancer during Palliative Care.
Mariyana, Rina; Allenidekania, Allenidekania; Nurhaeni, Nani
2018-01-01
Pain experienced by children can adversely affect their growth and development. Pain is a major health problem for cancer patients and remains an unresolved problem. To know how the experiences of mothers managing their children's pain during palliative care following cancer diagnosis. Pain experienced by children can adversely affect their growth and development. Using qualitative methods within a descriptive phenomenological approach, in-depth interviews were conducted with parents (mostly mothers) of eight children diagnosed with cancer. The data were collected using the snowball sampling method. Participants experienced in managing the pain of children with cancer. Analysis of the results identified 8 themes: the dimensions of pain experienced by children undergoing palliative care; mothers' physical and psychological responses; mothers' emotional responses; barriers encountered by mothers when taking care of their child at home; mothers' interventions to reduce their child's pain; mothers' efforts to distract their child from pain; giving encouragement when the child is in pain; and mothers' efforts and prayers to make their child comfort. It can be concluded that the child's pain is the main cause of mothers' stress and pressure and also affects the daily lives of mothers and children. Along with the most effective intervention, nurses need to provide mothers and children with adequate information about cancer pain.
Esmaeili, Reza; Hadian, Mohammad; Rashidian, Arash; Shariati, Mohammad; Ghaderi, Hossien
2016-04-01
When a country's health system is faced with fundamental flaws that require the redesign of financing and service delivery, primary healthcare payment systems are often reformed. This study was conducted with the purpose of exploring the experiences of risk-adjusted capitation payment of urban family physicians in Iran when it comes to providing primary health care (PHC). This is a qualitative study using the framework method. Data were collected via digitally audio-recorded semi-structured interviews with 24 family physicians and 5 executive directors in two provinces of Iran running the urban family physician pilot program. The participants were selected using purposive and snowball sampling. The codes were extracted using inductive and deductive methods. Regarding the effects of risk-adjusted capitation on the primary healthcare setting, five themes with 11 subthemes emerged, including service delivery, institutional structure, financing, people's behavior, and the challenges ahead. Our findings indicated that the health system is enjoying some major changes in the primary healthcare setting through the implementation of risk-adjusted capitation payment. With regard to the current challenges in Iran's health system, using risk-adjusted capitation as a primary healthcare payment system can lead to useful changes in the health system's features. However, future research should focus on the development of the risk-adjusted capitation model.
Bell, Stephanie; Dean, Judith; Gilks, Charles; Boyd, Mark A; Fitzgerald, Lisa; Mutch, Allyson; Baker, Peter; Neilsen, Graham; Gartner, Coral E
2017-07-18
Smoking is a leading cause of morbidity and premature mortality among people living with HIV (PLHIV), who have high rates of tobacco smoking. Vaporised nicotine products (VNPs) are growing in popularity as a quit aid and harm reduction tool. However, little is known about their acceptability and use among PLHIV. Using a pragmatic, uncontrolled, mixed methods design this exploratory clinical trial aims to examine the feasibility of conducting a powered randomised clinical trial of VNPs as a smoking cessation and harm reduction intervention among vulnerable populations, such as PLHIV who smoke tobacco. Convenience sampling and snowball methods will be used to recruit participants (N = 30) who will receive two VNPs and up to 12 weeks' supply of nicotine e-liquid to use in a quit attempt. Surveys will be completed at weeks 0 (baseline), 4, 8, 12 (end of treatment) and 24 (end of the study) and qualitative interviews at weeks 0 and 12. As far as we are aware, this feasibility study is the first to trial VNPs among PLHIV for smoking cessation. If feasible and effective, this intervention could offer a new approach to reducing the high burden of tobacco-related disease among PLHIV and other vulnerable populations.
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.
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.
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.
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.
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.
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.
Determining the disease management process for epileptic patients: A qualitative study
Hosseini, Nazafarin; Sharif, Farkhondeh; Ahmadi, Fazlollah; Zare, Mohammad
2016-01-01
Background: Epilepsy exposes patients to many physical, social, and emotional challenges. Thus, it seems to portray a complex picture and needs holistic care. Medical treatment and psychosocial part of epilepsy remain central to managing and improving the patient's qualify of life through team efforts. Some studies have shown the dimensions of self-management, but its management process of epilepsy patients, especially in Iran, is not clear. This study aimed to determine the disease management process in patients with epilepsy in Iran. Materials and Methods: This qualitative approach and grounded theory study was conducted from January 2009 to February 2012 in Isfahan city (Iran). Thirty-two participants were recruited by the goal-oriented, and snowball sample selection and theoretical sampling methods. After conducting a total of 43 in-depth interviews with the participants, the researchers reached data saturation. Data were analyzed using Strauss and Corbin method. Results: With a focus on disease management process, researchers found three main themes and seven sub-themes as a psychosocial process (PSP). The main themes were: perception of threat to self-identity, effort to preserve self-identity, and burn out. The psychosocial aspect of the disease generated one main variable “the perception of identity loss” and one central variable “searching for self-identity.” Conclusions: Participants attributed threat to self-identity and burn out to the way their disease was managed requiring efforts to preserve their identity. Recommendations consist of support programs and strategies to improve the public perception of epilepsy in Iran, help patients accept their condition and preserve self-identity, and most importantly, enhance medical management of epilepsy. PMID:26985223
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.
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.
Balsam, Kimberly F.; Lehavot, Keren; Beadnell, Blair; Circo, Elizabeth
2010-01-01
Objective Prior research has established that lesbian, gay, and bisexual (LGB) people experience higher rates of childhood abuse compared to heterosexuals. However, there has been little research on the mental health impact of these experiences, or how race/ethnicity might influence prevalence and mental health impact of childhood abuse in this population. The study’s objective was to examine the relationships between race/ethnicity and childhood abuse and their effect on mental health indicators in a national sample of LGB adults. Method Participants were recruited via the internet using snowball and targeted sampling methods. 669 LGB adults, 21% of whom were people of color, participated in an online survey. Participants completed the Childhood Trauma Questionnaire-Short Form, the Center for Epidemiologic Studies Depression Scale, the Patient Health Questionnaire Generalized Anxiety Disorder Scale, the PTSD Checklist-Civilian Version, and the Perceived Stress Scale Short-Form. Results Latina/o and Asian American participants reported the highest levels of physical abuse (p < .01), and Latina/o and African American participants reported the highest levels of sexual abuse (p < .01). Childhood emotional abuse was the strongest predictor of current psychopathology symptoms for all participants (ps < .01). Relative to White participants, emotional abuse showed a stronger relationship with current PTSD and anxiety symptoms for African American participants (ps < .01), and physical abuse showed a stronger relationship with current PTSD and anxiety symptoms for Latina/o participants (ps < .05). Conclusions Findings suggest that race/ethnicity may be an important factor when examining childhood abuse and mental health correlates among LGB populations. PMID:20658803
Determining the disease management process for epileptic patients: A qualitative study.
Hosseini, Nazafarin; Sharif, Farkhondeh; Ahmadi, Fazlollah; Zare, Mohammad
2016-01-01
Epilepsy exposes patients to many physical, social, and emotional challenges. Thus, it seems to portray a complex picture and needs holistic care. Medical treatment and psychosocial part of epilepsy remain central to managing and improving the patient's qualify of life through team efforts. Some studies have shown the dimensions of self-management, but its management process of epilepsy patients, especially in Iran, is not clear. This study aimed to determine the disease management process in patients with epilepsy in Iran. This qualitative approach and grounded theory study was conducted from January 2009 to February 2012 in Isfahan city (Iran). Thirty-two participants were recruited by the goal-oriented, and snowball sample selection and theoretical sampling methods. After conducting a total of 43 in-depth interviews with the participants, the researchers reached data saturation. Data were analyzed using Strauss and Corbin method. With a focus on disease management process, researchers found three main themes and seven sub-themes as a psychosocial process (PSP). The main themes were: perception of threat to self-identity, effort to preserve self-identity, and burn out. The psychosocial aspect of the disease generated one main variable "the perception of identity loss" and one central variable "searching for self-identity." Participants attributed threat to self-identity and burn out to the way their disease was managed requiring efforts to preserve their identity. Recommendations consist of support programs and strategies to improve the public perception of epilepsy in Iran, help patients accept their condition and preserve self-identity, and most importantly, enhance medical management of epilepsy.
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.
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.
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)
Zardosht, Roghayeh; Razavi, Mohammad Etezad; Ahmady, Soleiman
2018-01-01
Background Clinical education is an integral part of the surgical technology curriculum, in which students combine and integrate knowledge, skills, attitudes, values and philosophies of the profession. It is difficult to learn and adapt to different types of skills and roles in the operating room environment. Objective This qualitative study examines the difference between the clinical education of Surgical Technology and other clinical settings, and the challenges faced by students in the field, within the course. Methods This was a qualitative content analysis study conducted in 2016. The participants in this study were 16 baccalaureate surgical technology students of the University for Medical Sciences in Khorasan Razavi province. A semi-structured interview method was run to collect the required data. The sampling was initially purposive, then in the snowball method which continued until data saturation. All interviews were recorded, then transcribed, and analyzed using a continuous comparative method and conventional qualitative content analysis method. Results From the deep and rich descriptions of the participants, three themes including “stressful environment”, “controversy between anticipation of role and reality”, and “humiliating experiences” as well as a general theme of “bitter education” were obtained. Conclusion Students’ orientation before attending the operating room, accompanying, supporting, and a full-time attendance of the specialist instructor, strengthening the prerequisite knowledge and skills for the students in this field, teaching ethics, and professional interactions, play an important role in the student’s acceptance of the operating room, in the surgery team and the improvement of the quality of clinical education of these students. PMID:29629066
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.
The emotional eating and negative food relationship experiences of obese and overweight adults.
Ford, Tasha; Lee, HeeSoon; Jeon, MinJeong
2017-07-01
Overweight and obesity pose serious public health problems, affecting 68.8% of Americans. Previous research indicated that psychological factors played important roles in an individual's motivation to consume food. In particular, emotional eating, defined as overeating in response to negative affect, has received particular attention as a risk factor for obesity. This study explored and addressed the emotional factors involved in the development of emotional eating. A total of 10 Midwestern American male and female adults, previously diagnosed as medically overweight and obese, were recruited via online and print advertisement using maximum variation and snowball sampling methods. Using a semi-structured, face-to-face interview format, participants shared their perspectives about the development and persistence of emotional eating. The interviews were transcribed and Atlas.ti software was used to assist in thematic analysis of emotional eating. Study results yielded themes, such as emotional triggers, food cravings, comfort from foods, mindless eating, and childhood experiences. Findings indicated that participants generally lacked emotional self-care, but desired to decrease their emotional eating behaviors. Implications are discussed to construct creative, evidence-based treatments for the overweight and obese emotional eaters.
Using the results of a satisfaction survey to demonstrate the impact of a new library service model.
Powelson, Susan E; Reaume, Renee D
2012-09-01
In 2005, the University of Calgary entered into a contract to provide library services to the staff and physicians of Alberta Health Services Calgary Zone (AHS CZ), creating the Health Information Network Calgary (HINC). A user satisfaction survey was contractually required to determine whether the new library service model created through the agreement with the University of Calgary was successful. Our additional objective was to determine whether information and resources provided through the HINC were making an impact on patient care. A user satisfaction survey of 18 questions was created in collaboration with AHS CZ contract partners and distributed using the snowball or convenience sample method. Six hundred and ninety-four surveys were returned. Of respondents, 75% use the HINC library services. More importantly, 43% of respondents indicated that search results provided by library staff had a direct impact on patient care decisions. Alberta Health Services Calgary Zone staff are satisfied with the new service delivery model, they are taking advantage of the services offered, and using library provided information to improve patient care. © 2012 The authors. Health Information and Libraries Journal © 2012 Health Libraries Group.
Challenges in the rural family doctor system in Iran in 2013-14: a qualitative approach.
Nejatzadegan, Zohreh; Ebrahimipour, Hossien; Hooshmand, Elaheh; Tabatabaee, Seyed Saeed; Esmaili, Habibollah; vafaeeNajar, Ali
2016-08-01
Family doctor is a medical specialization that provides families and people of all ages, genders and diseases with comprehensive ongoing health services. The present study wasconducted to describe challenges in the rural family physician program from the perspective of family physician program directors and family doctors in Iran using a qualitative approach. We conducted interviews with 13 family physician program directors and 8 family doctors selected through purposive snowball sampling. The initial in-depth unstructured interviews were reviewed and transformed into semi-structured ones. The data obtained were analyzed in ATLAS.ti using the conceptual framework method. Nine main concepts (comprehensive planning, medical insurance system, compensation for services, performance evaluation, welfare facilities, recruiting and retaining a workforce, information system, culture-building and financing) and 27 subgroups emerged from the analysis of the data. The main challenges in the family physician program include cultural, economic and environmental factors and work conditions. The implementation of this program can be improved through building a community culture and exercising minor and major modifications. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Trying to find the quickest way: employed mothers' constructions of time for food.
Jabs, Jennifer; Devine, Carol M; Bisogni, Carole A; Farrell, Tracy J; Jastran, Margaret; Wethington, Elaine
2007-01-01
The study sought to develop an understanding of how employed mothers constructed time for food provisioning for themselves and their families. A grounded theory approach and semistructured, in-depth interviews. A metropolitan area of approximately 1 million people in the northeastern United States. Thirty-five low-wage employed mothers were purposively recruited to vary in occupation, race/ethnicity, education, household composition, and age using workplace, community, convenience, and snowball sampling. Low-wage employed mothers' constructions of time for food. Interview transcripts were analyzed using the constant comparative method. Most mothers expressed feelings of time scarcity. Mothers described 3 timestyles that reflected how they constructed time. Timestyles reflected mothers' experiences of strain and time scarcity, usual time management strategies, and sense of control over time. Mothers prioritized feeding their children but wanted to complete meals quickly in order to move on to other tasks. Recognizing issues of time scarcity and individual differences of timestyles and time management strategies can help researchers better understand food choice practices and assist practitioners in identifying practical food provisioning strategies for low-wage employed mothers. Food policies and recommendations should be evaluated for their relevance to the time scarcity and work strain issues that these mothers faced.
Qualitative investigation of the meanings of eating fruits and vegetables for adult couples.
Paisley, J; Sheeshka, J; Daly, K
2001-01-01
The purpose of this study was to develop a substantive theory expressing the meanings couples associated with eating fruits and vegetables. This inductive qualitative study was based on a grounded theory approach and employed the constant comparison method of data analysis. Data were collected using semistructured individual interviews and a life history approach. Ten adult couples, aged 20 to 60 years, with and without children, all of whom were born in North America, were recruited using modified snowball sampling. Two overarching themes emerged. The "should syndrome" describes a morality concerning fruit and vegetable consumption arising from a tension between the low status of these foods in participants' childhood homes and their contemporary idealized status. The creation of couple gastronomies expresses couples'efforts to construct their own food norms and practices within a context of changes in social norms and fruit and vegetable availability. The substantive theory, making choices that balance their lives, conveys the dynamic processes involved in participants' fruit and vegetable choices. Future research will determine the transferability of the "should syndrome" and new couples' receptiveness to trying new fruits and vegetables. Understanding the changing contexts of food choice may help nutrition professionals better support healthful eating.
Sherman, Ledric D; Griffith, Derek M
2018-05-01
Due to the high level of food-related chronic diseases for African American men, the purpose of this qualitative study was to induce ( n = 83) urban American men's perspective of their food environment considering different ethnic subgroups, built environment, and the temporal context using a phenomenological method and snowball sampling. Focus group interviews were audio-recorded, transcribed, and entered into ATLAS.ti to aid in establishing themes. African American men perceived that fast-food chains are their food choices and that they do not have any other healthy alternatives near their residential community. Their perspective of their current environment was primarily influenced by their formative years, the availability of current food environments, marketing and advertising of food on television, and the cost of eating healthy as compared to the cost of eating what is convenient to their residence. A central theme of the findings of this study is that the availability and accessibility of restaurants and food options are harmful to health over time. The finding suggests that future interventions should consider and incorporate how people develop and understand their current food practices and environment through the lens of time, not just their adult context.
The role of social networking sites in medical genetics research.
Reaves, Allison Cook; Bianchi, Diana W
2013-05-01
Social networking sites (SNS) have potential value in the field of medical genetics as a means of research subject recruitment and source of data. This article examines the current role of SNS in medical genetics research and potential applications for these sites in future studies. Facebook is the primary SNS considered, given the prevalence of its use in the United States and role in a small but growing number of studies. To date, utilization of SNS in medical genetics research has been primarily limited to three studies that recruited subjects from populations of Facebook users [McGuire et al. (2009); Am J Bioeth 9: 3-10; Janvier et al. (2012); Pediatrics 130: 293-298; Leighton et al. (2012); Public Health Genomics 15: 11-21]. These studies and a number of other medical and public health studies that have used Facebook as a context for recruiting research subjects are discussed. Approaches for Facebook-based subject recruitment are identified, including paid Facebook advertising, snowball sampling, targeted searching and posting. The use of these methods in medical genetics research has the potential to facilitate cost-effective research on both large, heterogeneous populations and small, hard-to-access sub-populations. Copyright © 2013 Wiley Periodicals, Inc.
Lesbian and bisexual health care.
Mathieson, C. M.
1998-01-01
OBJECTIVE: To explore lesbian and bisexual women's experiences with their family physicians to learn about barriers to care and about how physicians can provide supportive care. DESIGN: Qualitative study that was part of a larger study of lesbian and bisexual women's health care. SETTING: The province of Nova Scotia, both urban and rural counties. PARTICIPANTS: Ninety-eight self-identified lesbian or bisexual women who volunteered through snowball sampling. Women were interviewed by lesbian, bisexual, or heterosexual female interviewers. METHOD: Semistructured, audiotaped, face-to-face interviews, exploring questions about demographic information, sexual orientation, general health care patterns, preferences for health care providers, disclosure issues, health care information, access issues, and important health care services. Transcription of audiotapes of interviews was followed by content, thematic, and discourse analyses. Thematic analysis is reported in this paper. MAIN OUTCOME FINDINGS: Three themes important for family physicians emerged: the importance of being gay positive, barriers to care, and strategies for providing appropriate care. CONCLUSIONS: Family physicians are in a pivotal position to ensure supportive care for lesbian and bisexual women. Physicians need to recognize barriers to care and to use gay-positive strategies, paying attention to self-education, health history, and clinic environment. PMID:9721419
Management of organisational changes in a case of de-institutionalisation.
Parlalis, Stavros K
2011-01-01
This paper seeks to explore the development of a discharge programme in one learning disability hospital in Scotland. The study aims to concentrate on organisational developmental changes in that institution. The model of the management during the discharge programme was investigated. The aim of the study is to explore how the discharge programme developed, as seen under the lens of organisational change, in order to find out what kind of model of management is more suitable in similar programmes. A case study was employed. Data were collected by means of interviews. The interviews followed a structured format. The sample of the study had to be a purposive sample and the method of snowball sampling was used; finally, 28 interviews were conducted. A grounded approach was adopted for the data analysis. The software program QSR "NUD*IST" (version "N6") was used as a technical tool, in order to facilitate the data analysis. The findings of this study show that various management models were adopted in the four phases of the discharge programme. These different models represent a "quest" by the institution's management regarding the most appropriate model for managing the discharge programme. This study shows that this goes on continuously in organisations under transition until they settle down to a more permanent state. It was concluded that management models, which are composed of characteristics from the organic theory of organisational management, could apply in discharge programmes. The data gathered enabled the researcher to arrive at a model of management which is suitable for managing organisational changes in discharge programmes, the named "stakeholder management model".
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
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
Obrist, Seraina; Rogan, Slavko; Hilfiker, Roger
2016-01-01
Introduction. Falls are frequent in older adults and may have serious consequences but awareness of fall-risk is often low. A questionnaire might raise awareness of fall-risk; therefore we set out to construct and test such a questionnaire. Methods. Fall-risk factors and their odds ratios were extracted from meta-analyses and a questionnaire was devised to cover these risk factors. A formula to estimate the probability of future falls was set up using the extracted odds ratios. The understandability of the questionnaire and discrimination and calibration of the prediction formula were tested in a cohort study with a six-month follow-up. Community-dwelling persons over 60 years were recruited by an e-mail snowball-sampling method. Results and Discussion. We included 134 persons. Response rates for the monthly fall-related follow-up varied between the months and ranged from low 38% to high 90%. The proportion of present risk factors was low. Twenty-five participants reported falls. Discrimination was moderate (AUC: 0.67, 95% CI 0.54 to 0.81). The understandability, with the exception of five questions, was good. The wording of the questions needs to be improved and measures to increase the monthly response rates are needed before test-retest reliability and final predictive value can be assessed. PMID:27247571
Role of Cigarette Sensory Cues in Modifying Puffing Topography
Rees, Vaughan W.; Kreslake, Jennifer M.; Wayne, Geoffrey Ferris; O Connor, Richard J.; Cummings, K. Michael; Connolly, Gregory N.
2012-01-01
Background Human puffing topography promotes tobacco dependence by ensuring nicotine delivery, but the factors that determine puffing behavior are not well explained by existing models. Chemosensory cues generated by variations in cigarette product design features may serve as conditioned cues to allow the smoker to optimize nicotine delivery by adjusting puffing topography. Internal tobacco industry research documents were reviewed to understand the influence of sensory cues on puffing topography, and to examine how the tobacco industry has designed cigarettes, including modified risk tobacco products (MRTPs), to enhance puffing behavior to optimize nicotine delivery and product acceptability. Methods Relevant internal tobacco industry documents were identified using systematic searching with key search terms and phrases, and then snowball sampling method was applied to establish further search terms. Results Modern cigarettes are designed by cigarette manufacturers to provide sensory characteristics that not only maintain appeal, but provide cues which inform puffing intensity. Alterations in the chemosensory cues provided in tobacco smoke play an important role in modifying smoking behavior independently of the central effects of nicotine. Conclusions An associative learning model is proposed to explain the influence of chemosensory cues on variation in puffing topography. These cues are delivered via tobacco smoke and are moderated by design features and additives used in cigarettes. The implications for regulation of design features of modified risk tobacco products, which may act to promote intensive puffing while lowering risk perceptions, are discussed. PMID:22365895
Challenges of recovery in medium-term residential centers (camps)
Shamsalinia, Abbas; Nourozi, Kian; Khoshknab, Masoud Fallahi; Farhoudian, Ali
2014-01-01
Background: Addiction is a global problem for which effective treatment is crucial. Stopping the consumption of abused substances in a camp is a strong predictor of the success for the recovery process. The present study employed a qualitative approach to explore the camp recovery experiences in individuals with substance addictions. Methods: The research conducted in Iran’s northern cities with participants that included 17 men with a history of substance abuse, who were all engaged in the recovery process at the time of the study. They were invited to participate in the research based on a purposive and snowball sampling method. The data were collected by individual face-to-face and phone interviews using semi-structured questions. Data were then analyzed using conventional content analysis Results: three main categories were identified: selecting a camp: an appeal for rescue, substance deprivation crisis, and out of the frying pan into the frying pan or into the fire. Conclusion: Results showed that participants can be helped in the recovery process by the provision of public facilities and financial support for camps, by monitoring the performance of these centers and by attempting to address existing deficiencies. We concluded with three recommendations for improving services and preventing physical, psychological, and emotional damage to addicted individuals: remove unauthorized camps, establish camps with treatment designated to the needs of addicted individuals. PMID:25664307
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
Zardosht, Roghayeh; Moonaghi, Hossein Karimi; Razavi, Mohammad Etezad; Ahmady, Soleiman
2018-02-01
Clinical education is an integral part of the surgical technology curriculum, in which students combine and integrate knowledge, skills, attitudes, values and philosophies of the profession. It is difficult to learn and adapt to different types of skills and roles in the operating room environment. This qualitative study examines the difference between the clinical education of Surgical Technology and other clinical settings, and the challenges faced by students in the field, within the course. This was a qualitative content analysis study conducted in 2016. The participants in this study were 16 baccalaureate surgical technology students of the University for Medical Sciences in Khorasan Razavi province. A semi-structured interview method was run to collect the required data. The sampling was initially purposive, then in the snowball method which continued until data saturation. All interviews were recorded, then transcribed, and analyzed using a continuous comparative method and conventional qualitative content analysis method. From the deep and rich descriptions of the participants, three themes including "stressful environment", "controversy between anticipation of role and reality", and "humiliating experiences" as well as a general theme of "bitter education" were obtained. Students' orientation before attending the operating room, accompanying, supporting, and a full-time attendance of the specialist instructor, strengthening the prerequisite knowledge and skills for the students in this field, teaching ethics, and professional interactions, play an important role in the student's acceptance of the operating room, in the surgery team and the improvement of the quality of clinical education of these students.
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.
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.
'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.
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).
González Pérez, Rocío; Teresa Gijón Sánchez, M; José Escudero Carretero, M; Angeles Prieto Rodríguez, M; Carles March Cerdá, Joan; Ruiz Azarola, Ainhoa
2008-05-01
Patients' need for health information is widely recognized. The aim of this study was to determine how patients currently receive and rate this information. Additionally, we aimed to identify the needs and expectations of citizens of the autonomous region of Andalusia in this regard. We performed a qualitative research study involving semi-structured telephone interviews with participants. A total of 48 interviews were performed in people with different social and health profiles from a structural sample. The final selection of persons to be interviewed was made using the snow-ball sampling method. Interview material was analyzed by means of NUDIST vivo 1.1 software-aided content analysis. The interviewees reported receiving health information mainly from healthcare personnel. Supplementary information sources were the internet, associations and publications. The interviewees expressed different degrees of satisfaction with the health information received, depending on its understandability and the amount of detail provided. The persons interviewed reported that they would like to receive all the information possible on their health-illness-care process and would prefer this information to come mainly from physicians. Information about the health-illness-care process should center on practical issues. Physicians are the first and principal source of medical information and consequently communication skills should be promoted in this collective through training courses. Additionally, alternative sources of information used by citizens should be strengthened to provide high-quality health information. Copyright © 2008 Sociedad Española de Calidad Asistencial. Published by Elsevier Espana. All rights reserved.
Simonstein, Frida; Mashiach-Eizenberg, Michal
2016-02-01
The present study investigated a possible relationship between the attitudes toward genetic technologies and the understanding of genetics, reproduction, and reproductive risk among Israeli Arabs and Israeli Jews. The study included 203 respondents, who answered a structured self-report questionnaire. They were recruited using a snowball method, which increased the participation of Israeli Arabs in the sample, although the sample was not representative of the Israeli population as a whole (there were more Arabs and fewer men). The respondents in this study expressed a positive attitude toward genetic technologies, but were less in favor of using genetic tools for non-medical purposes. Respondents of both groups were not knowledgeable of genetics; however, they scored higher on the items related to reproductive risk, which suggests that some awareness about genetic risk exists in both sectors of the Israeli population. Nevertheless, Israeli Arabs were less positive than Israeli Jews regarding the application of genetic tools. Moreover, although an understanding of genetics correlated positively with the attitude among Arabs, it did not affect the attitude of Jews, who remained very positive, regardless of their level of understanding. This result suggests that other social and cultural factors, besides understanding, might be at work among these two major ethnic sectors. Further studies that integrate educational, social, and cultural aspects among ethnic sectors of the population are required to improve health services and genetic counselling in Israel and in other countries.
Haastrup, Oluwatosin O. O.; Buchan, John C.; Cassels-Brown, Andy; Cook, Colin
2015-01-01
Purpose: To evaluate the current quality “assurance” and “improvement” mechanisms, the knowledge, attitudes and practices of cataract surgeons in a large South African city. Methodology: A total of 17 in-depth semi-structured interviews were conducted with ophthalmologists in June 2012 at 2 tertiary institutions in the Republic of South Africa. Recruitment of the purposive sample was supplemented by snowball sampling. The study participants were 5 general ophthalmologists and 2 pediatric ophthalmologists; 4 senior and 4 junior registrars and a medical officer. Participants were interviewed by a trained qualitative interviewer. The interview lasted between 20 and 60 min. The interviews were recorded, transcribed verbatim and analyzed for thematic content. Results: Mechanisms for quality assurance were trainee logbooks and subjective senior staff observation. Clinicians were encouraged, but not obliged to self-audit. Quality improvement is incentivized by personal integrity and ambition. Poorly performing departments are inconspicuous, especially nationally, and ophthalmologists rely on the impression to gauge the quality of service provided by colleagues. Currently, word of mouth is the method for determining the better cataract surgical centers. Conclusion: The quality assurance mechanisms were dependent on insight and integrity of the individual surgeons. No structures were described that would ensure the detection of surgeons with higher than expected complication rates. Currently, audits are not enforced, and surgical outcomes are not well monitored due to concerns that this may lead to lack of openness among ophthalmologists. PMID:25949081
Haastrup, Oluwatosin O O; Buchan, John C; Cassels-Brown, Andy; Cook, Colin
2015-01-01
To evaluate the current quality "assurance" and "improvement" mechanisms, the knowledge, attitudes and practices of cataract surgeons in a large South African city. A total of 17 in-depth semi-structured interviews were conducted with ophthalmologists in June 2012 at 2 tertiary institutions in the Republic of South Africa. Recruitment of the purposive sample was supplemented by snowball sampling. The study participants were 5 general ophthalmologists and 2 pediatric ophthalmologists; 4 senior and 4 junior registrars and a medical officer. Participants were interviewed by a trained qualitative interviewer. The interview lasted between 20 and 60 min. The interviews were recorded, transcribed verbatim and analyzed for thematic content. Mechanisms for quality assurance were trainee logbooks and subjective senior staff observation. Clinicians were encouraged, but not obliged to self-audit. Quality improvement is incentivized by personal integrity and ambition. Poorly performing departments are inconspicuous, especially nationally, and ophthalmologists rely on the impression to gauge the quality of service provided by colleagues. Currently, word of mouth is the method for determining the better cataract surgical centers. The quality assurance mechanisms were dependent on insight and integrity of the individual surgeons. No structures were described that would ensure the detection of surgeons with higher than expected complication rates. Currently, audits are not enforced, and surgical outcomes are not well monitored due to concerns that this may lead to lack of openness among ophthalmologists.
Pain Management and Use of Opioids in Pediatric Oncology in India: A Qualitative Approach
Boydell, Katherine M.; Breakey, Vicky; Kurkure, Purna A.; Muckaden, Marian A.; Bouffet, Eric; Arora, Brijesh
2017-01-01
Purpose 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. Methods 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. Results 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. Conclusion 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. PMID:28831441
Chen, Jiang-peng; Wang, Hong; Liu, Liang
2013-09-01
To study the status of quality of life(QOL) on men who have sex with men (MSM) and it's relationship with social support among university students in Chongqing. Snowball sampling was applied to recruit the subjects on MSM for this study and multistage stratified cluster sampling method was used to recruit ordinary male college students. WHOQOL-BREF and SSRS questionnaires were used to collect information from both MSM and ordinary male college students. Scores from the physiological, psychological, social relations and environmental domains for QOL and total QOL were 13.82 ± 2.25, 13.14 ± 2.51, 13.24 ± 2.96, 12.44 ± 2.49 and 13.12 ± 2.16, respectively. Scores for all domains of QOL on MSM were lower than figures from ordinary male college students (P < 0.05). Results from Canonical correlation analysis revealed that subjective support and the use of support, together with psychological and social relations were the main factors that influencing the social support and quality of life in this population, respectively. The improvement of subjective feelings and proper use of social support and targeted interventions among this MSM population should accord to the different demographic characteristics, especially for those who did not have regular sexual partner or in gay circles, and for those who practice passive role during sexual act(as "0"), seemed to be helpful to improve their quality of life.
Kim, Nahyun; Hughes, Tonda L.; Park, Chang G.; Quinn, Laurie
2016-01-01
Abstract 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, χ2-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. PMID:26849530
Momartin, S; Silove, D; Manicavasagar, V; Steel, Z
2003-09-01
Refugee survivors of inter-ethnic warfare vary greatly in the extent and range of their trauma experiences. Discerning which experiences are most salient to generating and perpetuating disorders such as posttraumatic stress disorder (PTSD) is critical to the mounting rational strategies for targeted psychosocial interventions. In a sample of Bosnian Muslim refugees (n=126) drawn from a community centre and supplemented by a snowball sampling method, PTSD status and associated disability were measured using the clinician-administered PTSD Scale (CAPS) for DSM-IV. A principal components analysis (PCA) based on a pool of trauma items yielded four coherent trauma dimensions: Human Rights Violations, Threat to Life, Traumatic Loss and Dispossession and Eviction. A cluster analysis identified three subgroupings according to extent of trauma exposure. There were no differences in PTSD risk for the group most exposed to human rights violations (internment in concentration camps, torture) compared to the general war-exposed group. Logistic regression analysis using the dimensions derived from the PCA indicated that Threat to Life alone of the four trauma factors predicted PTSD status, a finding that supports the DSM-IV definition of a trauma. Both Threat to Life and Traumatic Loss contributed to symptom severity and disability associated with PTSD. It may be that human rights violations pose a more general threat to the survivor's future psychosocial adaptation in areas of functioning that extend beyond the confines of PTSD.
Health Information Management System for Elderly Health Sector: A Qualitative Study in Iran.
Sadoughi, Farahnaz; Shahi, Mehraban; Ahmadi, Maryam; Davaridolatabadi, Nasrin
2016-02-01
There are increasing change and development of information in healthcare systems. Given the increase in aging population, managers are in need of true and timely information when making decision. The aim of this study was to investigate the current status of the health information management system for the elderly health sector in Iran. This qualitative study was conducted in two steps. In the first step, required documents for administrative managers were collected using the data gathering form and observed and reviewed by the researcher. In the second step, using an interview guide, the required information was gathered through interviewing experts and faculty members. The convenience, purposeful and snowball sampling methods were applied to select interviewees and the sampling continued until reaching the data saturation point. Finally, notes and interviews were transcribed and content analysis was used to analyze them. The results of the study showed that there was a health information management system for the elderly health sector in Iran. However, in all primary health care centers the documentation of data was done manually; the data flow was not automated; and the analysis and reporting of data are also manually. Eventually, decision makers are provided with delayed information. It is suggested that the steward of health in Iran, the ministry of health, develops an appropriate infrastructure and finally puts a high priority on the implementation of the health information management system for elderly health sector in Iran.
Ouyang, Lin; Feng, Lian-gui; Ding, Xian-bin; Zhao, Jin-kou; Xu, Jing; Han, Mei; Zhou, Chao
2009-10-01
To examine HIV prevalence and related risk factors among men who have sex with men (MSM) in Chongqing, and to explore the feasibility of using respondent-driven sampling (RDS) in the survey. Based on results from formative research, a RDS survey was designed and conducted to collect demographic, behavioral and serologic data. RDSAT was used to calculate point estimation and confidence intervals. SPSS was used for bi-variate analysis using RDSAT exported weighed data. NETDRAW was used to draw network diagram. Among 617 subjects recruited, the adjusted HIV and syphilis prevalence rates were 16.8% and 10.9%, respectively. 73.0% of the subjects were 20 to 29 years old and 72.9% were officially registered residents of Chongqing. 83.4% were single, with the proportion of students the highest, accounting for 24.6%. During the last six months, 83.4% of them reported ever having anal sex, and 54.0% reported having unprotected anal sex. This survey confirmed that Chongqing had a higher reported HIV prevalence among MSM than from other Chinese cities. Comprehensive intervention services were required to address this alarmingly high prevalence, with focus on intervention through internet and those having syphilis infection. RDS seemed one of the effective ways of recruiting hidden MSM populations in Chongqing which had a large population of active MSM who did not frequently visit MSM venues as compared with snowball method.
Sockalingam, Sanjeev; Tehrani, Hedieh; Lin, Elizabeth; Lieff, Susan; Harris, Ilene; Soklaridis, Sophie
2016-04-01
To explore the perspectives of leaders in psychiatry and continuing professional development (CPD) regarding the relationship, opportunities, and challenges in integrating quality improvement (QI) and CPD. In 2013-2014, the authors interviewed 18 participants in Canada: 10 psychiatrists-in-chief, 6 CPD leaders in psychiatry, and 2 individuals with experience integrating these domains in psychiatry who were identified through snowball sampling. Questions were designed to identify participants' perspectives about the definition, relationship, and integration of QI and CPD in psychiatry. Interviews were recorded and transcribed. An iterative, inductive method was used to thematically analyze the transcripts. To ensure the rigor of the analysis, the authors performed member checking and sampling until theoretical saturation was achieved. Participants defined QI as a concept measured at the individual, hospital, and health care system levels and CPD as a concept measured predominantly at the individual and hospital levels. Four themes related to the relationship between QI and CPD were identified: challenges with QI training, adoption of QI into the mental health care system, implementation of QI in CPD, and practice improvement outcomes. Despite participants describing QI and CPD as mutually beneficial, they expressed uncertainty about the appropriateness of aligning these domains within a mental health care context because of the identified challenges. This study identified challenges with aligning QI and CPD in psychiatry and yielded a framework to inform future integration efforts. Further research is needed to determine the generalizability of this framework to other specialties and health care professions.
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.
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.
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.
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.
Gichane, Margaret W; Heap, Marion; Fontes, Mayara; London, Leslie
2017-07-01
Women with disabilities are at disproportionate risk for adverse pregnancy outcomes, however, there is limited information on their pregnancy histories. This mixed-methods study focuses on signing Deaf women whose access to health care may be compromised by language barriers related to their disability. To describe and compare the pregnancy outcomes and maternity service use of a sample of signing Deaf women of child-bearing age in Cape Town to the population of the Western Cape of South Africa. We interviewed 42 Deaf women selected by non-probability snowball sampling, using a structured questionnaire in South African Sign Language in Cape Town in July 2016. Average parity of the sample was similar to that of the Western Cape population. Most women had one or two children (74%). Thirty-one percent of women had experienced a miscarriage and 19% had terminated a pregnancy. Almost all women (96%) attended at least one antenatal appointment during their pregnancies, and all deliveries occurred at a health facility. Women primarily relied on writing to communicate during antenatal visits and labor/delivery. The majority of women reported communication issues due to limited interpretation services, and some reported experiencing mistreatment from hospital staff. This study provides novel information on the pregnancy histories of Deaf women. While maternal service usage was high, the quality of services were inadequate with reports of linguistic barriers and mistreatment. Findings suggest the need to improve maternity care for Deaf women through implementing interpretation services and providing sensitivity training to health care providers. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Paleomagnetism of the Neoproterozoic Mount Harper Volcanic Complex, Canada
NASA Astrophysics Data System (ADS)
Eyster, A. E.; Macdonald, F. A.; O'Connell, R. J.
2012-12-01
Paleomagnetism can be used to identify apparent polar wander, which involves contributions from plate tectonics and true polar wander. True polar wander events have been suggested to have played an important role throughout Earth's history. The Neoproterozoic Mount Harper Volcanic Complex (MHVC) provides paleomagnetic data that bears on this issue. The MHVC is located in the southern Ogilvie Mountains in the Yukon Territory, on the north-west corner of the Laurentian craton. The MHVC involves up to 1200 m of basaltic and andesitic flows. The MHVC reflects the propagating rifting event involved in the breakup of the supercontinent Rodinia. The MHVC is well dated with an age of 717.43± 0.14Ma from the top (Macdonald et al., Science, 2010). Below the MHVC are alluvial fan conglomerate and sandstone from Proterozoic normal faulting. Above the MHVC is a glacial diamictite dated to 716.47± 0.24 Ma and related to Snowball Earth glaciation (Macdonald et al., Science, 2010). Both block and core samples were collected from different members of the MHVC for paleomagnetic study. Included in the sampling were several stratigraphic sections. Alternating field and thermal stepwise demagnetization methods were used to analyze specimens. Magnetic components were determined using principal component analysis and Fisher statistical procedures were used to calculate mean directions. The stratigraphically sampled basalt flows yielded two components. One was a common secondary overprint, and the other was a high stability component which yielded two different directions. One pole is the same as the accepted Neoproterozoic Laurentian grand mean pole and the other is ˜50 degrees away from this grand mean pole. Several possible interpretations are explored- tectonic rotation, true polar wander or the presence of a non-dipolar geomagnetic field.
Exploring the situational motivation of medical specialists: a qualitative study
Kusurkar, Rashmi A.; Croiset, Gerda; Peerdeman, Saskia M.
2018-01-01
Objectives The aim was to obtain insight into the factors in the work environment that motivate or demotivate a medical specialist during his/her working day. Methods A qualitative ethnographic design was used, and a constructivist approach was adopted with the Self-Determination theory of motivation as a framework. Six medical specialists from VU University Medical Center in the Netherlands, recruited through convenience, snowball, and purposive sampling, were shadowed for one day each. Data were transcribed and open-coded. Themes were finalized through discussion and consensus. Results Sixty hours of observation data identified motivating and demotivating factors categorized into four themes that are important for specialists’ motivation. Informational technology issues are demotivating factors. Working with colleagues can be both a motivating and demotivating factor, e.g., filling in for each other through feelings of relatedness was motivating. Being in control of one’s planning through feelings of autonomy was motivating. Furthermore, patient care and teaching, especially in combination, stimulated specialists’ motivation. Regarding the design of the study, we found that situational motivation is indeed observable. Conclusions The basic psychological needs autonomy, competence, and relatedness are important for specialists’ motivation. Investing in a more motivating, open, transparent, and basic-needs- supportive work environment for medical specialists is necessary. Keywords: Continuing professional development, motivation, medical specialists, self-determination theory, qualitative research. PMID:29485972
Knox, Matthew C; Garner, Alexander; Dyason, Alan; Pearson, Thomas; Pit, Sabrina W
2017-02-15
To investigate reasons behind strong opposition to water fluoridation in regional New South Wales, Australia, and to make recommendations to improve community engagement. Few studies have used qualitative methodologies to understand the reasons for strong antifluoridation views. An understanding of these reasons could be useful when designing public campaigns to combat the strong antifluoridation message. The qualitative study used semistructured interviewing and thematic analysis. Ten participants were recruited using purposive and snowball sampling methods until data saturation was reached. Thematic analysis and graphical representation of themes assisted in analysing the data for logical connections and relationships. Six dominant themes and numerous subthemes were identified. Five of the major themes were reasons for opposition: scepticism, health effects, ethics, environmental impacts and economics. Each of these was inextricably linked to a sixth major theme: alternatives to fluoridation. All participants had strongly held antifluoridation views, and provided a unique insight into their perceptions and reasons for opposing water fluoridation. Concerns about 'fraudulent research' and the influence of industry on government bodies were novel themes. The concerns raised could be used to inform future population health campaigns, research, public education and resource-allocation decisions. Open community consultation may be able to address the issues raised in a nonjudgemental and collaborative manner.
Haberer, Jessica E; O’Neil, Ivy
2018-01-01
Objectives To explore (1) the social function of shisha cafes for young people living in the UK and (2) other alternative activities (existing or potential) that do not involve tobacco smoking. Methods We conducted qualitative interviews with young adults (age 18–30) in Leeds, UK. Snowballing sampling was used in selecting the participants. Interviews were audio-recorded and explored the perspectives and experiences of young people in as well as potential alternative activities. Data were transcribed and analysed thematically. Results Shisha use plays a central role in social interactions. Youth described using shisha because of emotional and sensory pleasure. Shisha use was implicitly endorsed by respected professionals, such as doctors and university lecturers, who were seen smoking it. Most, but not all, shisha smokers acknowledged that shisha use is harmful. Suggestions for reducing shisha use included use of non- tobacco alternatives, legislation to reduce access and alternative means for socialising, such as sports. Conclusion For young people in the UK, the known health dangers of shisha are outweighed by its social benefits and shisha is perceived as acceptable. Interventions to reverse the increase in shisha cafes should focus on both individual smoker as well as the community, without sacrificing the importance of social interactions. PMID:29654007
Bastani, Peivand; Dinarvand, Rasoul; SamadBeik, Mahnaz; Pourmohammadi, Kimia
2016-01-01
Objective: Pharmaceutical access for the poor is an essential factor in developing countries that can be improved through strategic purchasing. This study was conducted to identify the elements affecting price in order to enable insurance organizations to put strategic purchasing into practice. Methods: This was a qualitative study conducted through content analysis with an inductive approach applying a five-stage framework analysis (familiarization, identifying a thematic framework, indexing, mapping, and interpretation). Data analysis was started right after transcribing each interview applying ATLAS.ti. Data were saturated after 32 semi-structured interviews by experts. These key informants were selected purposefully and through snowball sampling. Findings: Findings showed that there are four main themes as Pharmaceutical Strategic Purchasing Requirements in Iran as follows essential and structural factors, international factors, economical factors, and legal factors. Moreover, totally 14 related sub-themes were extracted in this area as the main effective variables. Conclusion: It seems that paying adequate attention to the four present themes and 14 sub-themes affecting price can enable health system policy-makers of developing countries like Iran to make the best decisions through strategic purchasing of drugs by the main insurers in order to improve access and health in the country. PMID:26985434
Intrinsic rewards experienced by a group of dentists working with underserved populations.
Gardner, S P; Roberts-Thomson, K F; Winning, T A; Peterson, R
2014-09-01
The aim of this study was to explore, using qualitative methods, the intrinsic reasons why dentists work with underserved groups. Minority and marginalized groups of Australians suffer a greater burden of dental disease than the general population due to disparities in accessing care. Recruitment and retention of dentists to care for underserved groups is problematic due to personal, professional and structural reasons. What drives dentists to work with underserved groups is not widely known. Sixteen dentists were recruited using 'snowball' purposeful sampling. Semi-structured in-depth interviews were conducted. Thematic analysis was conducted on the transcriptions to identify themes. Five key themes emerged: (1) 'tapped on the shoulder', being personally approached or invited; (2) 'dental school experience', the challenges faced as a student; (3) 'empathic concern', the non-judgemental expressions of care toward others; (4) 'resilience', the ability to bounce back after setbacks; (5) 'intrinsic reward', the personal gain and satisfaction received. This study focuses on the intrinsic rewards which were found to be simple, unexpected, and associated with relieving pain, community engagement and making a difference. Emphasizing personal fulfilment and intrinsic reward could be useful when promoting dentistry as a career and when encouraging graduates to consider working with disadvantaged groups. © 2014 Australian Dental Association.
Challenging biopower: “Liquid cuffs” and the “Junkie” habitus
Gelpi-Acosta, Camila
2016-01-01
Background Methadone maintenance treatment program (MMTP) is associated with improved quality of life amongst many heroin users. Still, program adherence problems remain a fact. Aim To improve our understanding of MMTP “adherence problems”. Methods Using snowball sampling, two subgroups were recruited: MMTP enrollees and non-enrollees. A semi-structured questionnaire guided all in-depth interviews. Interviews were recorded, transcribed, hand-coded and analyzed using a grounded theory approach. Findings Of 28 participants, 23 were male and Fifteen were in MMTP. All were NYC residents. Most were Hispanic (57%) and Caucasian (32%). The average age was 38 years. Twenty-two had a General Educational Development or less. All were poor and 64% were homeless. Many do not enroll in MMTP to quit heroin but to avoid physical withdrawals. Once enrolled, problems emerge with program regulations and methadone's pharmacology. These they refer to as “liquid cuffs”. Drawing on Michel Foucault, methadone may be considered a disciplinary biopower technology that participants challenge using specific strategies. A “Junkie” habitus, crystallized by emotional and identitarian heroin-dispositions, also challenges biopower. Conclusions The “liquid cuffs” experience along with the “Junkie” habitus effectively challenge disciplinary biopower. Loosening program regulations may improve quality of services and reduce harm. PMID:26962271
The role of sensory perception in the development and targeting of tobacco products.
Carpenter, Carrie M; Wayne, Geoffrey Ferris; Connolly, Gregory N
2007-01-01
To examine tobacco industry research on smoking-related sensory effects, including differences in sensory perception across smoker groups, and to determine whether this research informed targeted product development and impacted the development of commercial tobacco products. We searched previously secret internal tobacco industry documents available online through document databases housed at Tobacco Documents Online, the British American Tobacco Document Archive and the Legacy Tobacco Documents Library. We identified relevant documents using a snowball sampling method to first search the databases using an initial set of key words and to then establish further search terms. Sensory research is a priority within the tobacco industry directly impacting commercial markets both in the United States and internationally. Sensory factors contribute to smoker satisfaction and product acceptance, and play an important role in controlling puffing behavior. Cigarette manufacturers have capitalized on distinct sensory preferences across gender, age and ethnic groups by tailoring products for specific populations. Regulation of tobacco products is needed to address product changes that are used to reinforce or contribute to tobacco dependence; for instance, the incorporation of additives that target attributes such as smoothness, harshness and aftertaste. Greater understanding of the role of sensory effects on smoking behavior may also help to inform the development of tobacco treatment options that support long-term tobacco abstinence.
MacFarlane, Anne; Galvin, Rose; O'Sullivan, Madeleine; McInerney, Chris; Meagher, Eoghan; Burke, Daniel; LeMaster, Joseph W
2017-06-01
There are increasing imperatives for patients and members of the public to engage as partners in identifying health research priorities. The use of participatory methods to engage stakeholders in health care in research prioritization is not commonly reported. This article analyses the use of World Cafés as a participatory method for research prioritization with marginalized communities in Ireland and the USA. The principles of purposeful and snowball sampling were followed in both settings and a diverse range of community and health care stakeholders participated (n = 63 Ireland and n = 55 USA). The principles for a classic World Café were employed but there were novel features in each setting as well. Stewart et al.'s (Patients' and clinicians' research priorities. Health Expect 2011; 14: 439-48, conceptual framework for patient engagement was adapted and used to comparatively analyse the strengths and weaknesses of the World Cafés, focusing on agenda setting, engagement with research processes, interactional features and outputs. Design principles for World Cafés were found to align with high-quality patient engagement for research prioritization in both settings. They served to facilitate meaningful collaboration among stakeholder groups in research prioritization (research agenda setting) and explored research priorities (engagement with research). The café ambience, emphasis on hospitality and self-facilitation created an environment for dialogues within and across participating groups (interactional features). There was a commitment to follow-up actions with reference to possible subsequent research (outputs). The World Café is a valuable, participatory, flexible method that can be used with community and health care stakeholders for research prioritization with marginalized communities. © The Author 2016. Published by Oxford University Press.
Use of qualitative methods to explore the quality-of-life construct from a consumer perspective.
Corring, Deborah J; Cook, Joanne V
2007-02-01
This study explored the construct of quality of life from the perspective of adults diagnosed as having severe and persistent mental illness, such as schizophrenia. Qualitative research strategies, specifically in-depth interviews (N=18) and focus groups (N=35), were used to collect data. Interviews and focus groups took place in hospitals, community clinics, community agencies, and clients' homes. A convenience, snowball sampling strategy was utilized. Analysis using the constant comparative method resulted in the identification of two dominant themes. These themes permeated the results, crossed all domains, influenced the linkages between domains, and clearly influenced how individuals frame their expectations regarding quality of life. The first theme was the presence of stigma and its effects on everyday life and future planning, and the second was the pervasive fear of the return of major positive symptoms of psychosis, such as hallucinations, delusions, and general loss of contact with reality. In addition, four quality-of-life domains were identified-the experience of illness, relationships, occupation, and sense of self. Many persons with mental illness simply wish for the basics in life-mental and physical health, supportive relationships, meaningful occupations, and a positive sense of self-believing that acquisition of these basics will lead to a more satisfactory quality of life. Ensuring that they are able to obtain the basics requires action on their part, by those who support them, by service providers that interact with them, and by a more accepting society.
Community pharmacists' views of the use of oral rehydration salt in Nigeria.
Oyetunde, Olubukola; Williams, Veronika
2018-06-01
Background Oral rehydration salt (ORS) is an affordable and effective intervention for the management of acute watery diarrhoea (AWD), especially in children under 5 years. A knowledge/practice gap exists among community pharmacists (CPs) in Lagos, Nigeria, and in many low to middle income countries. This gap results in underutilization of ORS for diarrhoea management. Objective The objective was to explore CPs' views of the barriers and facilitators to the use of ORS in practice. Setting Community pharmacy practices, Lagos, Nigeria. Methods Qualitative methods were used to explore pharmacists' views. Recruitment of participants were mainly at zonal meetings. A total of ten CPs participated based on maximum variation and snowballing sampling. Semi-structured interviews conducted covered knowledge, experiences and contextual issues. Interviews were audiorecorded, transcribed and analysed using framework approach to thematic analysis. Main outcome measure Pharmacists' views of barriers and facilitators to the use of ORS. Results Barriers to the use of ORS include caregivers' expectation for an antimicrobial, which was often explicitly and specifically for metronidazole. Also, CPs seemed to doubt applicability of ORS alone, therefore, responded to caregivers' complaints about ORS, by dispensing metronidazole. These barriers appeared to have normalised metronidazole for AWD treatment in this setting. Current facilitators include the caregivers' improved awareness of ORS and access to primary health centers that often resulted in increased demand for ORS in pharmacies. Conclusion CPs' views showed that caregivers' expectations for an antimicrobial may be the main barrier to the use of ORS in their practices.
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.
2013-01-01
Background Cohort studies provide an excellent opportunity to monitor changes in behaviour and disease transmission over time. In Australia, cohort studies of people who inject drugs (PWID) have generally focused on older, in-treatment injectors, with only limited outcome measure data collected. In this study we specifically sought to recruit a sample of younger, largely out-of-treatment PWID, in order to study the trajectories of their drug use over time. Methods Respondent driven sampling, traditional snowball sampling and street outreach methods were used to recruit heroin and amphetamine injectors from one outer-urban and two inner-urban regions of Melbourne, Australia. Information was collected on participants’ demographic and social characteristics, drug use characteristics, drug market access patterns, health and social functioning, and health service utilisation. Participants are followed-up on an annual basis. Results 688 PWID were recruited into the study. At baseline, the median age of participants was 27.6 years (IQR: 24.4 years – 29.6 years) and two-thirds (67%) were male. Participants reported injecting for a median of 10.2 years (range: 1.5 months – 21.2 years), with 11% having injected for three years or less. Limited education, unemployment and previous incarceration were common. The majority of participants (82%) reported recent heroin injection, and one third reported being enrolled in Opioid Substitution Therapy (OST) at recruitment. At 12 months follow-up 458 participants (71% of eligible participants) were retained in the study. There were few differences in demographic and drug-use characteristics of those lost to follow-up compared with those retained in the study, with attrition significantly associated with recruitment at an inner-urban location, male gender, and providing incomplete contact information at baseline. Conclusions Our efforts to recruit a sample of largely out-of-treatment PWID were limited by drug market characteristics at the time, where fluctuating heroin availability has led to large numbers of PWID accessing low-threshold OST. Nevertheless, this study of Australian injectors will provide valuable data on the natural history of drug use, along with risk and protective factors for adverse health outcomes associated with injecting drug use. Comprehensive follow-up procedures have led to good participant retention and limited attrition bias. PMID:23786848
Cheng, Gong; Huang, Lu-qi; Xue, Da-yuan; Zhang, Xiao-bo
2014-12-01
The survey of traditional knowledge related to Chinese materia medica resources is the important component and one of the innovative aspects of the fourth national survey of the Chinese materia medica resources. China has rich traditional knowledge of traditional Chinese medicine (TCM) and the comprehensive investigation of TCM traditional knowledge aims to promote conservation and sustainable use of Chinese materia medica resources. Building upon the field work of pilot investigations, this paper introduces the essential procedures and key methods for conducting the survey of traditional knowledge related to Chinese materia medica resources. The essential procedures are as follows. First is the preparation phrase. It is important to review all relevant literature and provide training to the survey teams so that they have clear understanding of the concept of traditional knowledge and master key survey methods. Second is the field investigation phrase. When conducting field investigations, survey teams should identify the traditional knowledge holders by using the 'snowball method', record the traditional knowledge after obtaining prior informed concerned from the traditional knowledge holders. Researchers should fill out the survey forms provided by the Technical Specification of the Fourth National Survey of Chinese Materia Medica Resources. Researchers should pay particular attention to the scope of traditional knowledge and the method of inheriting the knowledge, which are the key information for traditional knowledge holders and potential users to reach mutual agreed terms to achieve benefit sharing. Third is the data compilation and analysis phrase. Researchers should try to compile and edit the TCM traditional knowledge in accordance with intellectual property rights requirements so that the information collected through the national survey can serve as the basic data for the TCM traditional knowledge database. The key methods of the survey include regional division of Chinese materia medica resources, interview of key information holders and standardization of information.' In particular, using "snowball method" can effectively identify traditional knowledge holder in the targeted regions and ensuring traditional knowledge holders receiving prior informed concerned before sharing the information with researcher to make sure the rights of traditional knowledge holders are protected. Employing right survey methods is not only the key to obtain traditional knowledge related to Chinese materia medica resources, but also the pathway to fulfill the objectives of access and benefit sharing stipulated in Convention on Biological Resources. It will promote the legal protection of TCM traditional knowledge and conservation of TCM intangible, cultural heritage.
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)
Cleare, Sharlane S.
The purpose of this study is to explore the challenges experienced by Black female STEM doctoral students at a Majority White Institution. This study examined how, and to what extent did the Majority White Institution's STEM environment influenced such challenges. The qualitative phenomenological approach to this investigation utilized the lenses of Black Feminist Thought and Critical Race Feminism Theoretical Frameworks as interconnected lenses by which to conceptualize this phenomenon. This study answered the following question: What are the lived challenges experienced by Black female in a STEM doctoral program at a Majority White Institution? Purposeful and snowball sampling were employed to recruit participants for this investigation. Both sampling methods were selected because of their wide use in qualitative investigations, as well as their proven ability to precisely source quality participants (Biernacki, & Waldorf,1981; Palinkas, Horwitz, Green, Wisdom, Duan, & Hoagwood, (2015). Observations, in-depth semi-structured interviews, and focus groups were conducted with eleven (11) Black females STEM doctoral students currently studying at a large Majority White Institution in the Midwest. The findings from this study suggest that this is a phenomenon worthy of considerable attention. Research in the area of Black females in STEM doctoral programs at Majority White Institutions can be further expanded and updated. Therefore, this study will contribute and supplement existing literature on Black females in STEM doctoral programs at Majority White Institutions. Most importantly, the results obtained from this study can assist Majority White Institutions in the development and enhancement of programs and policies specifically geared towards addressing the needs of this underrepresented minority population segment.
Jensen, J L; Blanchard, I E; Bigham, B L; Carter, Aje; Brown, R; Socha, D; Brown, L H; Travers, A H; Craig, A M; Morrison, L J
2015-09-01
A recent mixed-methods study on the state of emergency medical services (EMS) research in Canada led to the generation of nineteen actionable recommendations. As part of the dissemination plan, a survey was distributed to EMS stakeholders to determine the anticipated impact and feasibility of implementing these recommendations in Canadian systems. An online survey explored both the implementation impact and feasibility for each recommendation using a five-point scale. The sample consisted of participants from the Canadian National EMS Research Agenda study (published in 2013) and additional EMS research stakeholders identified through snowball sampling. Responses were analysed descriptively using median and plotted on a matrix. Participants reported any planned or ongoing initiatives related to the recommendations, and required or anticipated resources. Free text responses were analysed with simple content analysis, collated by recommendation. The survey was sent to 131 people, 94 (71.8%) of whom responded: 30 EMS managers/regulators (31.9%), 22 researchers (23.4%), 15 physicians (16.0%), 13 educators (13.8%), and 5 EMS providers (5.3%). Two recommendations (11%) had a median impact score of 4 (of 5) and feasibility score of 4 (of 5). Eight recommendations (42%) had an impact score of 5, with a feasibility score of 3. Nine recommendations (47%) had an impact score of 4 and a feasibility score of 3. For most recommendations, participants scored the anticipated impact higher than the feasibility to implement. Ongoing or planned initiatives exist pertaining to all recommendations except one. All of the recommendations will require additional resources to implement.
Niang, Mbayang Ndiaye
2017-01-01
Telemedicine is considered to be an effective strategy to aid in the recruitment and retention of physicians in underserved areas and, in doing so, improve access to healthcare. Telemedicine’s use, however, depends on individual and contextual factors. Using a mixed methods design, we studied these factors in Senegal based on a micro, meso and macro framework. A quantitative questionnaire administered to 165 physicians working in public hospitals and 151 physicians working in district health centres was used to identify individual (micro) factors. This was augmented with qualitative descriptive data involving individual interviews with 30 physicians working in public hospitals, 36 physicians working in district health centres and 10 telemedicine project managers to identify contextual (meso and macro) factors. Physicians were selected using purposeful random sampling; managers through snowball sampling. Quantitative data were analyzed descriptively using SPSS 23 and qualitative data thematically using NVivo 10. At the micro level, we found that 72.1% of the physicians working in public hospitals and 82.1% of the physicians working in district health centres were likely to use telemedicine in their professional activities. At the meso level, we identified several technical, organizational and ethical factors, while at the macro level the study revealed a number of financial, political, legal, socioeconomic and cultural factors. We conclude that better awareness of the interplay between factors can assist health authorities to develop telemedicine in ways that will attract use by physicians, thus improving physicians’ recruitment and retention in underserved areas. PMID:28732028
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.
Noroozi, Mehdi; Farhadi, Mohammad Hassan; Armoon, Bahram; Farhoudian, Ali; Shushtari, Zahra Jorjoran; Sharhani, Asaad; Karimi, Salah Eddin; Sayadnasiri, Mohammad; Rezaei, Omid; Ghiasvand, Hesam
2018-05-17
Background The transition from non-injection to injection drug use dramatically increases the risk of transmitting HIV and other blood borne infections including hepatitis B virus (HBV) and hepatitis C virus (HCV). The aim of this study was to explore factors associated with the transition from first illicit drug use to first injection among drug users. Methods Using snowball sampling and convenience sampling through needle and syringe programmes (NSPs), we recruited 500 people who inject drugs (PWID) in Kermanshah, between September and December 2014. Trained interviewers collected data on socio-demographic characteristics, HIV testing and drug-related risk behaviors over the last month prior to interview using a structured questionnaire. Our main outcome variable was first illicit drug use to first injection (TIJ). TIJ was calculated by subtracting age at first drug injection from age of first illicit drug use. Results Overall, the average age at first drug use and injection were 21.4 [standard deviation (SD 5.6)] and 22.8 (SD 8.9), respectively. The average duration of injection was 6.0 (SD 4.6) years. Overall, the mean of TIJ for participants was 1.4 (IQR = 2, 4) years. Age of first injecting drug use negatively correlated with TIJ (R2 = 0.219, p = 0.001). Education level and socioeconomic status (SES), and negatively correlated with TIJ. Conclusion Some demographic factors and drug use characteristics including educational level, SES, knowledge of HIV status, age of initiating drug use, being a poly drug user and using methamphetamine were predictors of the time to transition.
Ly, Birama Apho; Labonté, Ronald; Bourgeault, Ivy Lynn; Niang, Mbayang Ndiaye
2017-01-01
Telemedicine is considered to be an effective strategy to aid in the recruitment and retention of physicians in underserved areas and, in doing so, improve access to healthcare. Telemedicine's use, however, depends on individual and contextual factors. Using a mixed methods design, we studied these factors in Senegal based on a micro, meso and macro framework. A quantitative questionnaire administered to 165 physicians working in public hospitals and 151 physicians working in district health centres was used to identify individual (micro) factors. This was augmented with qualitative descriptive data involving individual interviews with 30 physicians working in public hospitals, 36 physicians working in district health centres and 10 telemedicine project managers to identify contextual (meso and macro) factors. Physicians were selected using purposeful random sampling; managers through snowball sampling. Quantitative data were analyzed descriptively using SPSS 23 and qualitative data thematically using NVivo 10. At the micro level, we found that 72.1% of the physicians working in public hospitals and 82.1% of the physicians working in district health centres were likely to use telemedicine in their professional activities. At the meso level, we identified several technical, organizational and ethical factors, while at the macro level the study revealed a number of financial, political, legal, socioeconomic and cultural factors. We conclude that better awareness of the interplay between factors can assist health authorities to develop telemedicine in ways that will attract use by physicians, thus improving physicians' recruitment and retention in underserved areas.
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
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.
Psychosocial job stress and immunity: a systematic review.
Nakata, Akinori
2012-01-01
The purpose of this review was to provide current knowledge about the possible association between psychosocial job stress and immune parameters in blood, saliva, and urine. Using bibliographic databases (PubMed, PsychINFO, Web of Science, Medline) and the snowball method, 56 studies were found. In general, exposure to psychosocial job stress (high job demands, low job control, high job strain, job dissatisfaction, high effort-reward imbalance, overcommitment, burnout, unemployment, organizational downsizing, economic recession) had a measurable impact on immune parameters (reduced NK cell activity, NK and T cell subsets, CD4+/CD8+ ratio, and increased inflammatory markers). The evidence supports that psychosocial job stresses are related to disrupted immune responses but further research is needed to demonstrate cause-effect relationships.
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.
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.
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.
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.
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.
'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.
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.
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.
Bain, Mathew Gabriel; Lian, Cheah Whye; Thon, Chang Ching
2014-01-01
Context: Breaking of bad news is an important component in the management of cancer patients. Aims: This study aimed to assess the perceptions of breaking bad news of cancer diagnosis. Settings and Design: It was a cross-sectional study using Breaking Bad News Assessment Schedule (BAS) questionnaire on cancer patients in Serian district. Materials and Methods: Using snowballing sampling method, a total of 134 patients were interviewed face-to-face after the consent was obtained from each of the respondents. Statistical Analysis Used: Data was entered and analyzed using SPSS version 19.0. Results: 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). Conclusion: 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. PMID:24818107
Mascarenhas, Alekhya; Moore, Julia E.; Tricco, Andrea C.; Hamid, Jemila; Daly, Caitlin; Bain, Julie; Jassemi, Sabrina; Kiran, Tara; Baxter, Nancy; Straus, Sharon E.
2017-01-01
Background: The gender gap in academia is long-standing. Failure to ensure that our academic faculty reflect our student pool and national population deprives Canada of talent. We explored the gender distribution and perceptions of the gender gap at a Canadian university-affiliated, hospital-based research institute. Methods: We completed a sequential mixed-methods study. In phase 1, we used the research institute's registry of scientists (1999-2014) and estimated overall prevalence of a gender gap and the gap with respect to job description (e.g., associate v. full-time) and research discipline. In phase 2, we conducted qualitative interviews to provide context for phase 1 data. Both purposive and snowball sampling were used for recruitment. Results: The institute included 30.1% (n = 62) women and 69.9% (n = 144) men, indicating a 39.8% gender gap. Most full-time scientists (60.3%, n = 70) were clinicians; there were 54.2% more male than female clinician scientists. Ninety-five percent of basic scientists were men, indicating a 90.5% gap. Seven key themes emerged from 21 interviews, including perceived impact of the gender gap, factors perceived to influence the gap, recruitment trends, presence of institutional support, mentorship and suggestions to mitigate the gap. Several factors were postulated to contribute to the gender gap, including unconscious bias in hiring. Interpretation: A substantial gender gap exists within this research institute. Participants identified strategies to address this gap, such as establishing transparent search processes, providing opportunities for informal networking and mentorship of female scientists and establishing institutional support for work-life balance. PMID:28401131
Spatial change transformation of educational areas in Bandung
NASA Astrophysics Data System (ADS)
Yudi Permana, Asep; Wijaya, Karto
2017-12-01
Transformation is a total transfer process from a particular shape into a new figure which can be interpreted as the final stage of a changing process. Transformation, as a gradually progressive process, utilizes space and time factors becoming the aspect that greatly influences the change until reaching the ultimate stage. The changes are completed by responding to the influence of external and internal elements which will lead to a change from an early familiar form. The purpose of this research is to build theory based on phenomenon which occurs in the field as a result of space transformation process in Bandung so that it can be seen the setting adjustment of either physical or non-physical in the area becoming the city identity. The research method is qualitative research method with descriptive survey method approach. The focus of research is aimed at discrete phenomena in the field as an effort to disclose the background essence of the resulted theory formation. The study does not use a theoretical framework, yet there is a consistency in observing a discrete phenomenon of the grand tour results. The phenomenon is raised through the snowball sampling process. The process of collecting data, analyzing, and building theories is conducted jointly and iteratively within one research time range. The study results in the formation of space knowledge based on knitting and the value system of the users’ activities and the space settings. All users’ behaviors in using space are related to social, cultural, economic and creative activities in utilizing the existing space conditions. The results of this study provide an enrichment of architectural theory, planning theory and urban design theory having already existed.
Wong, Ee-Lynn; Tnay, Jessie Koh-Sing
2018-01-01
Background Female condom (FC) has been available for over 30 years, but it still lacks wide acceptability. To overcome misdirection and invagination occurring in FC and to provide a wider area of protection, Wondaleaf® (WL), a new-generation adhesive FC, was recently invented. This pioneering study sought to assess the acceptability and functional performance of WL among Malaysian women. Methods A mixed method survey was conducted in three cities of Malaysia, recruiting sexually active heterosexual women, aged 18–50, by snowball sampling method. Participants were provided with WL and initially surveyed to rate its performance in five coital usages over 2 months. After that, the participants underwent a second survey to rate their satisfaction and acceptability toward WL. Descriptive statistics on clinical failure rates were tabulated with correlational analysis performed to identify major variables contributing to WL’s functional performance and acceptability. Results Out of the 51 enrolled participants, 31 women completed the required surveys. WL’s total clinical failure rate was 2.60% (out of 155 condom uses) with above-average ratings of functional performance. The ease of use significantly correlated with ratings of no slippage and no misdirection. The confidence in WL’s safety features significantly correlated with a sense of empowerment and protection. Conclusion WL has a relatively low risk of clinical failures and an overall favorable acceptability among Malaysian women. However, this study also showed that its future usage largely depends on partner acceptability. It may have the potential of complementing the existing barrier toward contraceptive use. Further studies are needed to understand the global acceptability of WL. PMID:29440937
2012-01-01
Background Many women are unable to practice exclusive breastfeeding because they are separated from their infants while working. Expressing their breast milk helps them to continue breastfeeding. This study explores the perception and experiences related to the feasibility, acceptability and safety of breast milk expression among formally employed women in Kelantan, Malaysia. Methods A qualitative method using in-depth interviews was conducted from December 2008 to December 2009 among Malay women from urban and rural areas. A snowball sampling method was used to recruit the informants, and the interviews, which were facilitated by an interview guide, were audio-recorded and transcribed verbatim. Thematic analysis was conducted, with construction of codes and themes from each interview. Results Analysis of the interviews with 20 informants identified three themes related to breast milk expression. The themes were as follows: (i) lack of feasibility of expressing breast milk, (ii) negative feelings about expressing breast milk, and (iii) doubts about the safety and hygiene of expressed breast milk. The informants who did not practice exclusive breastfeeding believed that expressing their breast milk was not feasible, commonly because they felt there were not enough facilities for them. They also had negative feelings such as embarrassment. The safety and hygiene of the expressed breast milk was also their main concern. Conclusion More practical and focused education, as well as provision of facilities, is needed for women to effectively and safely express and store their breast milk. The issue of inadequate milk production should be emphasized, especially by encouraging them to express their breast milk as a way to improve milk production. PMID:22929649
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…
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.
Koita, Kadiatou; Novotny, Joseph; Kunene, Simon; Zulu, Zulizile; Ntshalintshali, Nyasatu; Gandhi, Monica; Gosling, Roland
2013-06-27
Swaziland has made great progress towards its goal of malaria elimination by 2015. However, malaria importation from neighbouring high-endemic Mozambique through Swaziland's eastern border remains a major factor that could prevent elimination from being achieved. In order to reach elimination, Swaziland must rapidly identify and treat imported malaria cases before onward transmission occurs. A nationwide formative assessment was conducted over eight weeks to determine if the imported cases of malaria identified by the Swaziland National Malaria Control Programme could be linked to broader social networks and to explore methods to access these networks. Using a structured format, interviews were carried out with malaria surveillance agents (6), health providers (10), previously identified imported malaria cases (19) and people belonging to the networks identified through these interviews (25). Most imported malaria cases were Mozambicans (63%, 12/19) making a living in Swaziland and sustaining their families in Mozambique. The majority of imported cases (73%, 14/19) were labourers and self-employed contractors who travelled frequently to Mozambique to visit their families and conduct business. Social networks of imported cases with similar travel patterns were identified through these interviews. Nearly all imported cases (89%, 17/19) were willing to share contact information to enable network members to be interviewed. Interviews of network members and key informants revealed common congregation points, such as the urban market places in Manzini and Malkerns, as well as certain bus stations, where people with similar travel patterns and malaria risk behaviours could be located and tested for malaria. This study demonstrated that imported cases of malaria belonged to networks of people with similar travel patterns. This study may provide novel methods for screening high-risk groups of travellers using both snowball sampling and time-location sampling of networks to identify and treat additional malaria cases. Implementation of a proactive screening programme of importation networks may help Swaziland halt transmission and achieve malaria elimination by 2015.
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.
Zandian, Hamed; Olyaeemanesh, Alireza; Takian, Amirhossein; Hosseini, Mostafa
2016-01-01
Introduction The Targeted Subsidies Law (TSL) was implemented in 2010 with a platform of improving equity in the Iran’s society. One of the objectives of the TSL was improving equity in Healthcare Financing (HCF), but a significant change has not occurred since then. The aim of this study was to analyze the challenges of the TSL to equity in the HCF in Iran. Methods In this interpretive qualitative study, 31 policy makers and health system experts were interviewed face to face from September 2014 to June 2015. A purposeful and snowball sampling method was used to select participants. Also, a document analysis was conducted on upstream documents. Assisted by MAXQDA 10, recorded interviews were transcribed verbatim and analyzed based on Framework Approach. Results Content analysis identified two themes and five sub-themes. Lack of justice in the healthcare system and lack of equity in the total socioeconomic structure of Iran were sub-themes identified as barriers to equity in HCF. Shortcomings in the formulation, implementation, and evaluation of the TSL were sub-themes identified as barriers in the policy process. The TSL did not achieve its intended objectives in the health sector because of the above-mentioned barriers, Conclusion The TSL, according to established goals, had no effect on the equity in HCF in Iran because of problems in the structure of the health system, socioeconomic status, and the policy process. To reach a more equitable HCF, it is advised that, when defining the related policies, various barriers be considered, such as those identified in our research. PMID:27053996
Báezconde-Garbanati, Lourdes; Beebe, Laura A; Pérez-Stable, Eliseo J
2007-10-01
To discuss systemic and conceptual issues that surround capacity building for tobacco control in traditionally underserved communities, by presenting two case studies, one in an American Indian community and another in a Hispanic/Latino community. Key informant interviews, cross-sectional surveys and case study methods were used to create community-specific conceptual frameworks for building capacity for tobacco control. These models of capacity building serve as the backdrop for the development of the two case studies. SETTING, PARTICIPANTS, MEASUREMENTS: Interview and survey participants were identified through convenience and snowball sampling, using a community-based participatory process in an American Indian community in Oklahoma and among the Hispanic/Latino Tobacco Education Partnership (H/LTEP) organizations in California. Using qualitative and quantitative methods, two case studies were created based on the results of interviews with key informants in each of the respective communities, outcomes of efforts to build capacity in tobacco control are presented. The extent to which American Indian and Hispanic/Latino communities have the capacity to address effectively the disproportionate burden of tobacco abuse is contingent upon the presence of leadership, collaboration, programs, distribution of funds and resources, development of policies and an underlying understanding of community strengths, history, values and participation. Common characteristics emerge from the case studies that help bridge differences in definition and measurement across both populations and programs. The conceptual frameworks for capacity building presented provide insight that enhances the ability of priority populations to engage in tobacco control strategies using culturally and language appropriate interventions.
Soltani, Akbar; Allaa, Maryam; Moosapour, Hamideh; Aletaha, Azadeh; Shahrtash, Farzaneh; Monajemi, Alireza; Arastoo, Tohid; Ahmadinejad, Maryam; Mirzazadeh, Azim; Khabaz Mafinejad, Mahboobeh
2017-01-01
Nowadays, improvement of thinking skills of students is one of the universally supported aims in the majority of medical schools. This study aims to design longitudinal theme of reasoning, problem-solving and decision-making into the undergraduate medical curriculum at Tehran University of Medical Sciences (TUMS). A participatory approach was applied to design the curriculum during 2009-2011. The project was conducted by the contribution of representatives of both basic and clinical faculty members, students and graduates at Tehran University of Medical Sciences. The first step toward integrating cognitive skills into the curriculum was to assemble a taskforce of different faculty and students, including a wide variety of fields with multidisciplinary expertise using nonprobability sampling and the snowball method. Several meetings with the contribution of experts and some medical students were held to generate the draft of expected outcomes. Subsequently, the taskforce also determined what content would fit best into each phase of the program and what teaching and assessment methods would be more appropriate for each outcome. After a pilot curriculum with a small group of second-year medical students, we implemented this program for all first-year students since 2011 at TUMS. Based on findings, the teaching of four areas, including scientific and critical thinking skills (Basic sciences), problem-solving and reasoning (Pathophysiology), evidence-based medicine (Clerkship), and clinical decision-making (Internship) were considered in the form of a longitudinal theme. The results of this study could be utilized as a useful pattern for integration of psycho-social subjects into the medical curriculum.
Mascarenhas, Alekhya; Moore, Julia E; Tricco, Andrea C; Hamid, Jemila; Daly, Caitlin; Bain, Julie; Jassemi, Sabrina; Kiran, Tara; Baxter, Nancy; Straus, Sharon E
2017-01-01
The gender gap in academia is long-standing. Failure to ensure that our academic faculty reflect our student pool and national population deprives Canada of talent. We explored the gender distribution and perceptions of the gender gap at a Canadian university-affiliated, hospital-based research institute. We completed a sequential mixed-methods study. In phase 1, we used the research institute's registry of scientists (1999-2014) and estimated overall prevalence of a gender gap and the gap with respect to job description (e.g., associate v. full-time) and research discipline. In phase 2, we conducted qualitative interviews to provide context for phase 1 data. Both purposive and snowball sampling were used for recruitment. The institute included 30.1% ( n = 62) women and 69.9% ( n = 144) men, indicating a 39.8% gender gap. Most full-time scientists (60.3%, n = 70) were clinicians; there were 54.2% more male than female clinician scientists. Ninety-five percent of basic scientists were men, indicating a 90.5% gap. Seven key themes emerged from 21 interviews, including perceived impact of the gender gap, factors perceived to influence the gap, recruitment trends, presence of institutional support, mentorship and suggestions to mitigate the gap. Several factors were postulated to contribute to the gender gap, including unconscious bias in hiring. A substantial gender gap exists within this research institute. Participants identified strategies to address this gap, such as establishing transparent search processes, providing opportunities for informal networking and mentorship of female scientists and establishing institutional support for work-life balance.
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.
Wang, Karen H; Ray, Natasha J; Berg, David N; Greene, Ann T; Lucas, Georgina; Harris, Kenn; Carroll-Scott, Amy; Tinney, Barbara; Rosenthal, Marjorie S
2017-09-01
Sustaining collaborations between community-based organization leaders and academic researchers in community-engaged research (CEnR) in the service of decreasing health inequities necessitates understanding the collaborations from an inter-organizational perspective. We assessed the perspectives of community leaders and university-based researchers conducting community-engaged research in a medium-sized city with a history of community-university tension. Our research team, included experts in CEnR and organizational theory, used qualitative methods and purposeful, snowball sampling to recruit local participants and performed key informant interviews from July 2011-May 2012. A community-based researcher interviewed 11 community leaders, a university-based researcher interviewed 12 university-based researchers. We interviewed participants until we reached thematic saturation and performed analyses using the constant comparative method. Unifying themes characterizing community leaders and university-based researchers' relationships on the inter-organizational level include: 1) Both groups described that community-engaged university-based researchers are exceptions to typical university culture; 2) Both groups described that the interpersonal skills university-based researchers need for CEnR require a change in organizational culture and training; 3) Both groups described skepticism about the sustainability of a meaningful institutional commitment to community-engaged research 4) Both groups described the historical impact on research relationships of race, power, and privilege, but only community leaders described its persistent role and relevance in research relationships. Challenges to community-academic research partnerships include researcher interpersonal skills and different perceptions of the importance of organizational history. Solutions to improve research partnerships may include transforming university culture and community-university discussions on race, power, and privilege.
Ting, Rachel Sing-Kiat; Wong, Ee-Lynn; Tnay, Jessie Koh-Sing
2018-01-01
Female condom (FC) has been available for over 30 years, but it still lacks wide acceptability. To overcome misdirection and invagination occurring in FC and to provide a wider area of protection, Wondaleaf ® (WL), a new-generation adhesive FC, was recently invented. This pioneering study sought to assess the acceptability and functional performance of WL among Malaysian women. A mixed method survey was conducted in three cities of Malaysia, recruiting sexually active heterosexual women, aged 18-50, by snowball sampling method. Participants were provided with WL and initially surveyed to rate its performance in five coital usages over 2 months. After that, the participants underwent a second survey to rate their satisfaction and acceptability toward WL. Descriptive statistics on clinical failure rates were tabulated with correlational analysis performed to identify major variables contributing to WL's functional performance and acceptability. Out of the 51 enrolled participants, 31 women completed the required surveys. WL's total clinical failure rate was 2.60% (out of 155 condom uses) with above-average ratings of functional performance. The ease of use significantly correlated with ratings of no slippage and no misdirection. The confidence in WL's safety features significantly correlated with a sense of empowerment and protection. WL has a relatively low risk of clinical failures and an overall favorable acceptability among Malaysian women. However, this study also showed that its future usage largely depends on partner acceptability. It may have the potential of complementing the existing barrier toward contraceptive use. Further studies are needed to understand the global acceptability of WL.
Kramer, Erik J; Dodington, James; Hunt, Ava; Henderson, Terrell; Nwabuo, Adaobi; Dicker, Rochelle; Juillard, Catherine
2017-09-01
Violent injury is the second most common cause of death among 15- to 24-year olds in the US. Up to 58% of violently injured youth return to the hospital with a second violent injury. Hospital-based violence intervention programs (HVIPs) have been shown to reduce injury recidivism through intensive case management. However, no validated guidelines for risk assessment strategies in the HVIP setting have been reported. We aimed to use qualitative methods to investigate the key components of risk assessments employed by HVIP case managers and to propose a risk assessment model based on this qualitative analysis. An established academic hospital-affiliated HVIP served as the nexus for this research. Thematic saturation was reached with 11 semi-structured interviews and two focus groups conducted with HVIP case managers and key informants identified through snowball sampling. Interactions were analyzed by a four-member team using Nvivo 10, employing the constant comparison method. Risk factors identified were used to create a set of models presented in two follow-up HVIP case managers and leadership focus groups. Eighteen key themes within seven domains (environment, identity, mental health, behavior, conflict, indicators of lower risk, and case management) and 141 potential risk factors for use in the risk assessment framework were identified. The most salient factors were incorporated into eight models that were presented to the HVIP case managers. A 29-item algorithmic structured professional judgment model was chosen. We identified four tiers of risk factors for violent reinjury that were incorporated into a proposed risk assessment instrument, VRRAI. Copyright © 2017 Elsevier Inc. All rights reserved.
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.
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.
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.
Pain and Pain Management Among University Students: Online Survey and Web-Based Education.
Tse, Mimi Mun Yee; Tang, Angel; Budnick, Andrea; Ng, Shamay Sheung Mei; Yeung, Suey Shuk Yu
2017-05-01
Pain is common among university students. Unrelieved pain has adverse impacts on their quality of life. In this study, a pain management Web site was developed to distribute an online survey and provide Web-based pain education to university students. Participants were recruited from eight universities in Hong Kong using snowball sampling. The online survey included 37 items examining pain situations, pain management strategies, knowledge about self-medication, and demographic data of the participants. A total of 387 students participated and over 90 percent of them reported pain in the past 6 months. Around one-third of participants did not take any action to manage their pain. Pharmacological method was the most common strategy for students to relieve pain (37.2 percent). The use of over-the-counter (OTC) drug for pain relief was high (n = 214). However, OTC drug knowledge score was significantly higher among health-related group than nonhealth-related group (p < 0.001). There were 188 students who also read the Web-based pain education and completed the evaluation on its usefulness. Nonhealth-related students reported significantly higher scores of self-perceived usefulness for the online education than the health-related students (p < 0.001). Findings suggested the need to consider the service users' background when developing online education program in the future.
Lived Experiences of Educational Leaders in Iranian Medical Education System: A Qualitative Study
Sohrabi, Zohreh; Kheirkhah, Masoomeh; Vanaki, Zohreh; Arabshahi, Kamran Soltani; Farshad, Mohammad Mahdi; Farshad, Fatemeh; Farahani, Mansoureh Ashgale
2016-01-01
Introduction: High quality educational systems are necessary for sustainable development and responding to the needs of society. In the recent decades, concerns have increased on the quality of education and competency of graduates. Since graduates of medical education are directly involved with the health of society, the quality of this system is of high importance. Investigation in the lived experience of educational leaders in the medical education systems can help to promote its quality. The present research examines this issue in Iran. Methodology: The study was done using content-analysis qualitative approach and semi-structured interviews. The participants included 26 authorities including university chancellors and vice-chancellors, ministry heads and deputies, deans of medical and basic sciences departments, education expert, graduates, and students of medical fields. Sampling was done using purposive snowball method. Data were analyzed using conventional content analysis. Findings: Five main categories and 14 sub-categories were extracted from data analysis including: quantity-orientation, ambiguity in the trainings, unsuitable educational environment, personalization of the educational management, and ineffective interpersonal relationship. The final theme was identified as “Education in shadow”. Conclusion: Personalization and inclusion of personal preferences in management styles, lack of suitable grounds, ambiguity in the structure and process of education has pushed medical education toward shadows and it is not the first priority; this can lead to incompetency of medical science graduates. PMID:26925915
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.
HIV Incidence and Risk Factors in Chinese Young Men Who Have Sex with Men—A Prospective Cohort Study
Zhang, Hongbo; Dou, Zhi; Mi, Guodong; Ruan, Yuhua; Shen, Limei; Min, Xiangdong; Lan, Guanghua; Li, Fan; Li, Tian; Ning, Zhen; Wu, Guohui; She, Min; Wu, Zunyou
2014-01-01
Objectives To assess HIV incidence and its associated risk factors among young men who have sex with men (YMSM) in urban areas, China. Design The study used a prospective cohort study design and standard diagnostic tests. Methods A twelve-month prospective cohort study was conducted among YMSM (18–25 years old) in 8 large cities in China. The participants were recruited via snowball sampling. A total of 1102 HIV-negative YMSM completed baseline assessment, 878 YMSM participants completed 6-month follow-up, and 902 completed 12-month follow-up. HIV was screened by an enzyme-linked immunosorbent assay and confirmed with Western Blot. Syphilis was screened via rapid plasma reagent and confirmed by treponema pallidum particle agglutination assay. Results 78 HIV seroconversions were identified within 1168.4 person-year observations yielding an incidence rate of 6.7 per 100 person-years. HIV seroconversion was associated with non-student status (RR = 2.61, 90% CI = 1.3–5.26), low HIV transmission knowledge (RR = 8.87, 90% CI = 2.16–36.43), and syphilis infection (RR = 5.04, 90% CI = 2.57–9.90). Conclusions Incidence of HIV among YMSM is high in urban areas of China. Interventions measures are required to contain the HIV epidemic within this population. PMID:24878586
Strategies for improved French-language health services
Gauthier, Alain P.; Timony, Patrick E.; Serresse, Suzanne; Goodale, Natalie; Prpic, Jason
2015-01-01
Abstract Objective To identify strategies to improve the quality of health services for Francophone patients. Design A series of semistructured key informant interviews. Setting Northeastern Ontario. Participants A total of 18 physicians were interviewed. Ten physicians were interviewed in French, 7 physicians were women, and 10 physicians were located in urban communities. Methods Purposive and snowball sampling strategies were used to conduct a series of semistructured key informant interviews with family physicians practising in communities with a large Francophone population. Principles of grounded theory were applied, guided by a framework for patient-professional communication. Results were inductively derived following an iterative data collection–data analysis process and were analyzed using a detailed thematic approach. Main findings Respondents identified several strategies for providing high-quality French-language health services. Some were unique to non–French-speaking physicians (eg, using appropriate interpreter services), some were unique to French-speaking physicians (eg, using a flexible dialect), and some strategies were common to all physicians serving French populations (eg, hiring bilingual staff or having pamphlets and posters in both French and English). Conclusion Physicians interviewed for this study provided high-quality health care by attributing substantial importance to effective communication. While linguistic patient-to-physician concordance is ideal, it might not always be possible. Thus, conscious efforts to attenuate communication barriers are necessary, and several effective strategies exist. PMID:26505060
Milne, Nikki; Choy, Nancy Low; Leong, Gary M; Hughes, Roger; Hing, Wayne
2016-01-01
This study explored current physiotherapy practice trends for management of children who are overweight or obese. The professional needs of physiotherapists working with this population were also assessed, including the perceived need for physiotherapy clinical guidelines for prevention and management of children with obesity. A cross-sectional survey design was used, with questionnaires purposefully distributed through 13 key physiotherapy services throughout Australia. Snowball sampling resulted in completed questionnaires from 64 physiotherapists who provided services to children. Half (n=33, 52%) of respondents provided services specifically to overweight or obese children. Of those providing services, one-quarter had prior training specific to working with this population. Most used multi-disciplinary models (n=16, 76%) and provided under 5h of obesity-related services each week (n=29, 88%). Half (n=16, 49%) used body mass index as an outcome measure but more (n=25, 76%) used bodyweight. Only 14 (42%) assessed motor skills. The majority of respondents (n=57, 89%) indicated a need for physiotherapy guidelines to best manage overweight and obese children. Professional development priorities included: 'Educating children and families', 'Assessment methods' and 'Exercise prescription' for overweight and obese children. This data provides workforce intelligence to guide future professional training and inform development of clinical guidelines for physiotherapists in prevention and management of children with obesity and related chronic disease.
The ethics and safety of medical student global health electives
Dell, Evelyn M.; Varpio, Lara; Petrosoniak, Andrew; Gajaria, Amy
2014-01-01
Objectives To explore and characterize the ethical and safety challenges of global health experiences as they affect medical students in order to better prepare trainees to face them. Methods Semi-structured interviews were conducted with 23 Canadian medical trainees who had participated in global health experiences during medical school. Convenience and snowball sampling were utilized. Using Moustakas’s transcendental phenomenological approach, participant descriptions of ethical dilemmas and patient/trainee safety problems were analyzed. This generated an aggregate that illustrates the essential meanings of global health experience ethical and safety issues faced. Results We interviewed 23 participants who had completed 38 electives (71%, n=27, during pre-clinical years) spend-ing a mean 6.9 weeks abroad, and having visited 23 countries. Sixty percent (n=23) had pre-departure training while 36% (n=14) had post-experience debriefing. Three macro-level themes were identified: resource disparities and provision of care; navigating clinical ethical dilemmas; and threats to trainee safety. Conclusions Medical schools have a responsibility to ensure ethical and safe global health experiences. However, our findings suggest that medical students are often poorly prepared for the ethical and safety dilemmas they encounter during these electives. Medical students require intensive pre-departure training that will prepare them emotionally to deal with these dilemmas. Such training should include discussions of how to comply with clinical limitations. PMID:25341214
Jack, Alexander; Egan, Vincent
2016-03-01
Paranoid thinking is prevalent in the non-clinical population and cognitive mechanisms of heuristic reasoning and jumping to conclusions bias contributes to its formation and maintenance. This study investigated the degree to which paranoia, perceived environmental risk, heuristic reasoning and jumping to conclusions bias (measured with the beads task) contribute to misinterpretation of neutral stimuli, and whether this informed judgements regarding vulnerability to threat and crime. It is also investigated whether impulsiveness is a confounding factor on the beads task. Two hundred participants were recruited using a snowball-sampling method for a quantitative cross-sectional study. Participants reported demographic information, three psychometric questionnaires and two experimental tasks via an online paradigm hosted by the Bristol Online Survey tool. Participants with high paranoia scores perceived their environment to be more dangerous than those with low scores. Participants with high paranoia scores also overestimated threat in neutral stimuli and had high expectations of future victimisation. Jumping to conclusions on the beads task did not predict fear of crime outcomes, but was predicted by impulsivity. Participants who demonstrated paranoid thinking were more likely to reside in perceived dangerous neighbourhoods and overestimate threat. While this could indicate a paranoid heuristic, it is a potentially rational response to prior experiences of crime and victimisation. Implications and suggestions for future research are discussed. © The Author(s) 2015.
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
HIV behavioural risks and the role of work environment among Chinese male sex workers in Hong Kong.
Wong, William C W; Leung, Phil W S; Li, C W
2012-01-01
Male sex workers are a highly marginalised group in Hong Kong and it is increasingly so with an influx of them travelling from mainland China to work as "freelance" sex workers. This study aimed to measure important work environment variables that might affect the likelihood of condom use among male sex workers working in Hong Kong. A cross-sectional survey of 161 participants recruited by snowball and convenience sampling methods through outreach workers of a local non-governmental organization was conducted in 2007-2008. Only 27.4%, 54.7% and 42.6% reported consistent condom use when engaging in oral, anal and vaginal sex, respectively. Logistic regression shows unsafe sex was nearly four times (OR=3.41; 95%CI 1.51-7.69) as common in institutionalised male sex workers as among their independent counterparts. Lack of condoms provided at workplaces was a major barrier in this socio-legal context and was strongly associated with condom non-use amongst institutionalised sex workers (OR= 10.86; 95%CI 2.94-40.17). The present study finds that when compared with independent Male sex workers (MSWs), institutionalised MSWs were older, less educated, earned a higher income but more likely to engage in unsafe sex with their clients and their partners. Public health physicians must work with law-enforcing authorities to provide clear guidelines to remove these HIV prevention barriers.
Spencer, Sarah; Meer, Talia
2017-01-01
Background While the provision of gender affirming care for transgender people in South Africa is considered legal, ethical, and medically sound, and is—theoretically—available in both the South African private and public health sectors, access remains severely limited and unequal within the country. As there are no national policies or guidelines, little is known about how individual health care professionals providing gender affirming care make clinical decisions about eligibility and treatment options. Method Based on an initial policy review and service mapping, this study employed semi-structured interviews with a snowball sample of twelve health care providers, representing most providers currently providing gender affirming care in South Africa. Data were analysed thematically using NVivo, and are reported following COREQ guidelines. Results Our findings suggest that, whilst a small minority of health care providers offer gender affirming care, this is almost exclusively on their own initiative and is usually unsupported by wider structures and institutions. The ad hoc, discretionary nature of services means that access to care is dependent on whether a transgender person is fortunate enough to access a sympathetic and knowledgeable health care provider. Conclusion Accordingly, national, state-sanctioned guidelines for gender affirming care are necessary to increase access, homogenise quality of care, and contribute to equitable provision of gender affirming care in the public and private health systems. PMID:28704458
O’Malley, Denalee; Hudson, Shawna V.; Nekhlyudov, Larissa; Howard, Jenna; Rubinstein, Ellen; Lee, Heather S.; Overholser, Linda S.; Shaw, Amy; Givens, Sarah; Burton, Jay S.; Grunfeld, Eva; Parry, Carly; Crabtree, Benjamin F.
2016-01-01
PURPOSE This study describes the experiences of early implementers of primary care-focused cancer survivorship delivery models. METHODS Snowball sampling was used to identify innovators. Twelve participants (five cancer survivorship primary care innovators and seven content experts) attended a working conference focused on cancer survivorship population strategies and primary care transformation. Data included meeting discussion transcripts/field notes, transcribed in-depth innovator interviews, and innovators’ summaries of care models. We used a multi-step immersion/crystallization analytic approach, guided by a primary care organizational change model. RESULTS Innovative practice models included: 1) a consultative model in a primary care setting; 2) a primary care physician (PCP)-led, blended consultative/panel-based model in an oncology setting; 3) an oncology nurse navigator in a primary care practice; and 4) two sub-specialty models where PCPs in a general medical practice dedicated part of their patient panel to cancer survivors. Implementation challenges included: (1) lack of key stakeholder buy-in; (2) practice resources allocated to competing (non-survivorship) change efforts; and (3) competition with higher priority initiatives incentivized by payers. CONCLUSIONS Cancer survivorship delivery models are potentially feasible in primary care; however, significant barriers to widespread implementation exist. Implementation efforts would benefit from increasing the awareness and potential value-add of primary care-focused strategies to address survivors’ needs. PMID:27277895
Informal caregivers in hospitals: Opportunities and threats.
Amiresmaili, Mohammadreza; Emrani, Zahra
2018-05-20
High hospital costs are a challenge that health system face. Additionally, studies identified manpower deficiency as a problem in health system. Hospital is a place where patients with different physical and mental conditions come to. Their families and friends' companionship can facilitate this situation for them. This study illustrates the roles of informal caregivers in hospital. This is a phenomenological qualitative study. Data were gathered through semistructured interviews. We interviewed 22 informal caregivers and 9 nurse staffs from different departments of hospital. They were selected through purposeful and snowball sampling approach. The framework method was used for data analysis. We found 3 main themes including (a) roles of informal caregivers, (b) opportunities of presence of the informal caregivers in the hospital, and (c) threats of presence of informal caregivers. This study shows some roles for informal caregivers including mental supports, consultation, decision-making, and care roles. Concerning the shortage of manpower in Iran's hospitals, nurses have less time to take care of each patient; therefore, using informal caregivers as an implicit strategy to overcome nursing shortage and to reduce hospital costs seems to be beneficial. We suggest that an appropriate plan is necessary to make use of them for filling this gap to some extent, as well as providing training sessions and facilities for companions acting as informal caregivers. Copyright © 2018 John Wiley & Sons, Ltd.
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
Framework for Considering Productive Aging and Work.
Schulte, Paul A; Grosch, James; Scholl, Juliann C; Tamers, Sara L
2018-05-01
The U.S. population is experiencing a demographic transition resulting in an aging workforce. The objective of this article is to elucidate and expand an approach to keep that workforce safe, healthy, and productive. This article elucidates the framework for the National Center for Productive Aging at Work of the National Institute for Occupational Safety and Health. Subject matter experts used a snowball method to review published literature to substantiate elements in the framework. Evidence-based literature supports a productive aging framework for the workforce involving the following elements: 1) life span perspective; 2) comprehensive and integrated approaches to occupational safety and health; 3) emphasis on positive outcomes for both workers and organizations; and 4) supportive work culture for multigenerational issues. The productive aging framework provides a foundational and comprehensive approach for addressing the aging workforce.
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…
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…
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.
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
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
Chen, Xiaodong Phoenix; Sullivan, Amy M; Alseidi, Adnan; Kwakye, Gifty; Smink, Douglas S
Providing resident autonomy in the operating room (OR) is one of the major challenges for surgical educators today. The purpose of this study was to explore what approaches expert surgical teachers use to assess residents' readiness for autonomy in the OR. We particularly focused on the assessments that experts make prior to conducting the surgical time-out. We conducted semistructured in-depth interviews with expert surgical teachers from March 2016 to September 2016. Purposeful sampling and snowball sampling were applied to identify and recruit expert surgical teachers from general surgery residency programs across the United States to represent a range of clinical subspecialties. All interviews were audio-recorded, deidentified, and transcribed. We applied the Framework Method of content analysis, discussed and reached final consensus on the themes. We interviewed 15 expert teachers from 9 institutions. The majority (13/15) were Program or Associate Program Directors; 47% (7/15) primarily performed complex surgical operations (e.g., endocrine surgery). Five themes regarding how expert surgical teachers determine residents' readiness for OR autonomy before the surgical time-out emerged. These included 3 domains of evidence elicited about the resident (resident characteristics, medical knowledge, and beyond the current OR case), 1 variable relating to attending characteristics, and 1 variable composed of contextual factors. Experts obtained one or more examples of evidence, and adjusted residents' initial autonomy using factors from the attending variable and the context variable. Expert surgical teachers' assessments of residents' readiness for OR autonomy included 5 key components. Better understanding these inputs can contribute to both faculty and resident development, enabling increased resident autonomy and preparation for independent practice. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
McAleese, Sara; Clyne, Barbara; Matthews, Anne; Brugha, Ruairí; Humphries, Niamh
2016-06-30
Health professionals, particularly doctors, nurses and midwives, are in high demand worldwide. Therefore, it is important to assess the future plans and likelihood of return of emigrating health professionals. Nevertheless, health professionals are, by definition, a difficult population to track/survey. This exploratory study reports on the migration intentions of a sample of doctors, nurses and midwives who had emigrated from Ireland, a high-income country which has experienced particularly high outward and inward migration of health professionals since the year 2000. Health professionals who had emigrated from Ireland were identified via snowball sampling through Facebook and invited to complete a short online survey composed of closed and open response questions. A total of 388 health professionals (307 doctors, 73 nurses and 8 midwives) who had previously worked in Ireland completed the survey. While over half had originally intended to spend less than 5 years in their destination country at the time of emigration, these intentions changed over time, with the desire to remain abroad on a permanent basis increasing from 10 to 34 % of doctor respondents. Only a quarter of doctors and a half of nurses and midwives intended to return to practice in Ireland in the future. The longer health professionals remain abroad, the less likely they are to return to their home countries. Countries should focus on the implementation of retention strategies if the 'carousel' of brain drain is to be interrupted. This would allow source countries to benefit from their investments in training health professionals, rather than relying on international recruitment to meet health system staffing needs. Improved data collection systems are also needed to track the migratory patterns and changing intentions of health professionals. Meanwhile, social networking platforms offer alternative methods of filling this information gap.
Implementation of a reimbursed medication review program: Corporate and pharmacy level strategies.
MacKeigan, Linda D; Ijaz, Nadine; Bojarski, Elizabeth A; Dolovich, Lisa
In 2006, the Ontario drug plan greatly reduced community pharmacy reimbursement for generic drugs. In exchange, a fee-for-service medication review program was introduced to help patients better understand their medication therapy and ensure that medications were taken as prescribed. A qualitative study of community pharmacy implementation strategies was undertaken to inform a mixed methods evaluation of the program. To describe strategies used by community pharmacies to implement a government-funded medication review service. Key informant interviews were conducted with pharmacy corporate executives and managers, as well as independent pharmacy owners. All pharmacy corporations in the province were approached; owners were purposively sampled from the registry of the pharmacist licensing body to obtain diversity in pharmacy attributes; and pharmacy managers were identified through a mix of snowball and registry sampling. Thematic qualitative coding and analysis were applied to interview transcripts. 42 key informants, including 14 executives, 15 managers/franchisees, and 11 owners, participated. The most common implementation strategy was software adaptation to flag eligible patients and to document the service. Human resource management (task shifting to technicians and increasing the technician complement), staff training, and patient identification and recruitment processes were widely mentioned. Motivational strategies including service targets and financial incentives were less frequent but controversial. Strategies typically unfolded over time, and became multifaceted. Apart from the use of targets in chain pharmacies only, strategies were similar across pharmacy ownership types. Ontario community pharmacies appeared to have done little preplanning of implementation strategies. Strategies focused on service efficiency and quantity, rather than quality. Unlike other jurisdictions, many managers supported the use of targets as motivators, and very few reported feeling pressured. This detailed account of a range of implementation strategies may be of practical value to community pharmacy decision makers. Copyright © 2017 Elsevier Inc. All rights reserved.
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
Van Wyk, Jacqueline; Joubert, Robin
2017-01-01
Background Primary healthcare (PHC) is central to increased access and transformation in South African healthcare. There is limited literature about services required by occupational therapists in PHC. Despite policy being in place, the implementation of services at grassroots level does not always occur adequately. Objectives This study aimed at gaining an understanding of the challenges of being disabled and the services required by occupational therapists (OTs) in rural communities in order to better inform the occupational therapy (OT) training curriculum. Method An exploratory, descriptive qualitative design was implemented using purposive sampling to recruit 23 community healthcare workers from the uGu district. Snowball sampling was used to recruit 37 members of the uGu community, which included people with disability (PWD) and caregivers of PWDs. Audio-recorded focus groups and semi-structured interviews were used to collect data, which were thematically analysed. Ethical approval was obtained from the Biomedical and Research Ethics Committee of the University of KwaZulu-Natal (BE248/14). Results Two main themes emerged namely: firstly, the challenges faced by the disabled community and secondly appropriate opportunities for intervention in PHC. A snapshot of the social and physical inaccessibility challenges experienced by the community was created. Challenges included physical and sexual abuse, discrimination and marginalisation. Community-based rehabilitation and ideas for health promotion and prevention were identified as possible strategies for OT intervention. Conclusion The understanding of the intervention required by OT in PHC was enhanced through obtaining the views of various stakeholders’ on the role. This study highlighted the gaps in community-based services that OTs should offer in this context. PMID:28730063
Ilić, Dragan; Sipetić, Sandra; Bjegović, Vesna
2010-01-01
HIV in Serbia is most often transmitted through sexual contact, and therefore numerous prevention activities are geared towards sex workers (SW). To analyse the differences in knowledge, attitudes and risky behaviour between indoor and street SW in Belgrade; to examine the accessibility of health services to this vulnerable group. In this behavioural cross-sectional study, 113 street and 78 indoor SW were included. The sampling method used was snowball samples. Data were gathered through structured questionnaires. Around 15% of respondents used drugs intravenously. Around 60% of SW used a condom during the last sexual intercourse with their private partner, and around 90% with a commercial partner. Indoor SW had lower levels of education more often than outdoor SW, and they used marijuana, sedatives and painkillers on a daily basis. A significantly higher number of indoor SW were informed about HIV, HBV and HCV testing, and that the risk for HIV infection is not lower ifa condom is used exclusively for vaginal sex. Indoor SW reported using health services and testing and counselling for HIV, HBV and HCV more frequently than outdoor SW. Outdoor SW had significantly more sex partners in the previous month than indoor SW. Indoor SW recognized more frequently that providing sex services posed a higher risk for HIV infection. The results of this research study show that even though outdoor SW had higher levels of education than indoor SW, their level of knowledge about HIV transmission was lower and they reported more risky behaviour than indoor SW. Data show that both groups reported not taking care of their health.
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.
Kenyon, Lisa K; Dole, Robin L; Kelly, Stephanie P
2013-12-01
To prepare students for pediatric practice, the professional (entry-level) curriculum must reflect the essential knowledge, skills, and abilities (KSA) required for pediatric physical therapist practice. The aim of this study was to develop consensus concerning the pediatric-specific KSA that should be expected of doctor of physical therapy (DPT) students at various points in the curriculum: prior to a pediatric clinical education experience, after a pediatric clinical education experience, and at the end of a DPT program. The study was conducted using the Delphi method. Purposive and snowball sampling were used to recruit pediatric academic faculty and pediatric clinical instructors. Three Web-based survey rounds were used to achieve consensus, defined as agreement among ≥70% of informants. The first round identified pediatric-specific KSA that were essential for DPT students to demonstrate at the identified points in the curriculum. In the second round, informants indicated their level of agreement with each item identified in the first round. Items that achieved consensus were included in the third round, in which informants rated the level of proficiency that DPT students should demonstrate related to pediatric-specific KSA. Consensus revealed the informants' perspectives concerning pediatric-specific KSA that a DPT student should be able to demonstrate at the identified curricular points. Consensus was reached on items in the curricular categories of basic science and foundations for practice; common pediatric diagnoses/pathologies, examination, interventions/plan of care/documentation; and general skills and abilities. Limitations included the small sample size and the potential for informants to feel uncomfortable prioritizing KSA. This study is an initial step toward identifying pediatric-specific KSA that should be demonstrated by DPT students.
Porsch, Lauren M; Dayananda, Ila; Dean, Gillian
2016-01-01
Purpose: Transgender individuals experience barriers to healthcare, including discrimination in care provision and lack of knowledge about transgender health. We assessed New York City (NYC) transgender and gender nonconforming individuals' sexual and reproductive health (SRH) needs, access to services, and interest in receiving services from Planned Parenthood of NYC (PPNYC). Methods: We conducted an anonymous Internet-based survey of transgender individuals residing in NYC from September to December 2014 by using snowball sampling. Results: Data were analyzed from 113 surveys. Although 74% (71/96) of respondents avoided or delayed healthcare in the past year, most respondents adhered to medically indicated SRH screenings. In the past year, 64% (45/70) and 67% (46/69) of respondents were tested for HIV and other sexually transmitted infections, respectively. In the past 3 years, 80% (39/49) of respondents received clinical breast/chest examinations and 83% (35/42) of eligible individuals received Pap tests. Respondents most often received care at LGBT specialty clinics (35% [37/105]) or at private doctors' offices (31% [32/105]). Eighteen percent (19/107) had ever been to a Planned Parenthood health center. On a four-point scale, respondents rated the following factors as most influential on whether they would seek care at PPNYC: assurance that staff received transsensitivity training (mean 3.8), the existence of gender identity nondiscrimination policies (mean 3.7), and the availability of transgender-specific services, such as hormone therapy (mean 3.7). Conclusions: Although the majority of transgender individuals in our sample received recommended SRH screenings, respondents reported barriers to accessing needed medical care. Healthcare organizations interested in better serving the transgender community should ensure a high level of training around transsensitivity and explore the provision of transgender-specific services.
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
Medical end-of-life practices among Canadian physicians: a pilot study.
Marcoux, Isabelle; Boivin, Antoine; Mesana, Laura; Graham, Ian D; Hébert, Paul
2016-01-01
Medical end-of-life practices are hotly debated in Canada, and data from other countries are used to support arguments. The objective of this pilot study was twofold: to adapt and validate a questionnaire designed to measure the prevalence of these practices in Canada and the underlying decision-making process, and to assess the feasibility of a nationally representative study. In phase 1, questionnaires from previous studies were adapted to the Canadian context through consultations with a multidisciplinary committee and based on a scoping review. The modified questionnaire was validated through cognitive interviews with 14 physicians from medical specialties associated with a higher probability of being involved with dying patients recruited by means of snowball sampling. In phase 2, we selected a stratified random sample of 300 Canadian physicians in active practice from a national medical directory and used the modified tailored method design for mail and Web surveys. There were 4 criteria for success: modified questions are clearly understood; response patterns for sensitive questions are similar to those for other questions; respondents are comparable to the overall sampling frame; and mean questionnaire completion time is less than 20 minutes. Phase 1: main modifications to the questionnaire were related to documentation of all other medical practices (including practices intended to prolong life) and a question on the proportionality of drugs used. The final questionnaire contained 45 questions in a booklet style. Phase 2: of the 280 physicians with valid addresses, 87 (31.1%) returned the questionnaire; 11 of the 87 declined to participate, for a response rate of 27.1% (n = 76). Most respondents (64 [84%]) completed the mail questionnaire. All the criteria for success were met. It is feasible to study medical end-of-life practices, even for practices that are currently illegal, including the intentional use of lethal drugs. Results from this pilot study support conducting a large national study, but additional strategies would be necessary to improve the response rate.
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.
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.
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
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.
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.
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.
Moran, Mika R.; Werner, Perla; Doron, Israel; HaGani, Neta; Benvenisti, Yael; King, Abby C.; Winter, Sandra J.; Sheats, Jylana L.; Garber, Randi; Motro, Hadas; Ergon, Shlomit
2018-01-01
Walking is a central form of physical activity among older adults that is associated with the physical environment at various scales. This mixed-methods study employs a concurrent nested design to explore objective and perceived environmental characteristics of older adults’ local walking routes. This was achieved by integrating quantitative Geographic Information System (GIS) data with qualitative data obtained using the Stanford Discovery Tool (DT). Fifty-nine community-dwelling middle-aged and older adults (14 men and 45 women aged 50+) were recruited in a snowball approach through community centers in the city of Haifa (Israel). Four neighborhood environment themes were identified: pedestrian infrastructure, access to destinations, aesthetics, and environmental quality. Both geometrical traits (i.e., distance, slope) and urban features (i.e., land-uses, greenery) of the route may impact the experience of walking. The findings thus highlight the importance of micro-scale environmental elements in shaping environmental perceptions, which may consequently influence the choice of being active. PMID:27992252
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
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…
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…
2012-01-01
Background Up till now, nomadic communities in Africa have been the primary focus of ethnoveterinary research. Although mainly arable and/or mixed arable/pastoral farmers, Ameru of central Kenya are known to have a rich history of ethnoveterinary knowledge. Their collective and accumulative ethnoveterinary knowledge (EVK) is likely to be just as rich and worth documenting. The aim of the study was to document and analyse the ethnoveterinary knowledge of the Ameru. Methods Non-alienating, dialogic, participatory action research (PAR) and participatory rural appraisal (PRA) approaches involving 21 women and men aged between 50 and 79 years old were utilized. A combination of snowball and purposive sampling methods were used to select 21 key respondents. The methods comprised a set of triangulation approach needed in EVK for non-experimental validation of ethnoknowledge of the Ameru. Results A total of 48 plant species distributed in 26 families were documented with details of diseases/ill-health conditions, parts of plants used and form of preparation and administration methods applied to different animal groups. Of these families, Fabaceae had the highest number of species (16.67%), followed by Solanaceae (12.5%), Asteraceae and Euphorbiacea (each comprising 8.33%), Lamiaceae (6.25%), Apocynaceae and Boraginaceae (each comprising 4.17%), while the rest of the 19 families, each was represented by a single plant species. About 30 livestock diseases/ill-health conditions were described, each treated by at least one of the 48 plant species. Most prevalent diseases/ill-health conditions included: - anaplasmosis, diarrhea, East Coast fever, pneumonia, helminthiasis, general weakness and skin diseases involving wounds caused by ectoparasites. Conclusion The study showed that there was a rich knowledge and ethnopractices for traditional animal healthcare amongst the Ameru. This study therefore provides some groundwork for elucidating the efficacy of some of these plants, plant products and ethnopractices in managing livestock health as further research may lead to discovery of useful ethnopharmaceutical agents applicable in livestock industry. PMID:23044218
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.
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
Condom use and associated factors among men who have sex with men in Togo, West Africa
Bakai, Tchaa Abalo; Ekouevi, Didier Koumavi; Tchounga, Boris Kévin; Balestre, Eric; Afanvi, Kossivi Agbélénko; Goilibe, Kariyiare Benjamin; Kassankogno, Yao; Pitche, Vincent Palokinam
2016-01-01
Introduction In 2011, the prevalence of HIV among men who have sex with men (MSM) in Togo was estimated at 19.6% compared to 3.4% in the general population. This study aimed to describe condom use and associated factors among MSM in Togo. Methods In 2011, a cross-sectional survey was conducted using the snowball sampling method among MSM in Togo. This study enrolled MSM aged 18 years and above who reported having sexual contact with other men within the last 30 days. A standardized survey form was used for data collection, and multivariate analyses were performed. Results A total of 724 MSM were included in this study. The median age was 25 years [22-28], 90.3% had at least a secondary school level. The sexual practices during the last sexual encounter with another man included: insertive anal sex (62.2%), receptive anal sex (56.6%), oral sex (33.8%) and oral-anal sex (8.6%). A condom was used during the last insertive and receptive anal encounters in 78.4% and 81.2% of the time, respectively. In multivariate analysis, condom use was positively associated with previous participation in HIV/STD prevention activities (aOR=1.72; 95% CI=[1.09-2.71]), with the consideration of the last sexual partner as a casual one (aOR=1.87; 95% CI=[1.24-2.82]) and with having at least a secondary school level (aOR=2.40; 95% CI=[1.22-4.69]). Conclusion One out of five MSM did not use a condom during the last anal encounter with another man. HIV prevention programs in Africa should develop specific interventions targeting MSM to reduce the incidence of HIV in this hidden population. PMID:27279945
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
Manchaiah, Vinaya; Danermark, Berth; Ahmadi, Tayebeh; Tomé, David; Zhao, Fei; Li, Qiang; Krishna, Rajalakshmi; Germundsson, Per
2015-01-01
Hearing loss is one of the most common chronic conditions in older adults. In audiology literature, several studies have examined the attitudes and behavior of people with hearing loss; however, not much is known about the manner in which society in general views and perceives hearing loss. This exploratory study was aimed at understanding the social representation of hearing loss (among the general public) in the countries of India, Iran, Portugal, and the UK. We also compared these social representations. The study involved a cross-sectional design, and participants were recruited using the snowball sampling method. A total of 404 people from four countries participated in the study. Data were collected using a free-association task where participants were asked to produce up to five words or phrases that came to mind while thinking about hearing loss. In addition, they were also asked to indicate if each word they presented had positive, neutral, or negative associations in their view. Data were analyzed using various qualitative and quantitative methods. The most frequently occurring categories were: assessment and management; causes of hearing loss; communication difficulties; disability; hearing ability or disability; hearing instruments; negative mental state; the attitudes of others; and sound and acoustics of the environment. Some categories were reported with similar frequency in most countries (eg, causes of hearing loss, communication difficulties, and negative mental state), whereas others differed among countries. Participants in India reported significantly more positive and fewer negative associations when compared to participants from Iran, Portugal, and the UK. However, there was no statistical difference among neutral responses reported among these countries. Also, more differences were noted among these countries than similarities. These findings provide useful insights into the public perception of hearing loss that may prove useful in public education and counseling.
Noroozi, Mehdi; Rahimi, Ebrahim; Ghisvand, Hessam; Qorbani, Mostafa; Sharifi, Hamid; Noroozi, Alireza; Farhoudian, Ali; Marshall, Brandon D L; Jorjoran Shoshtari, Zahra; Karimi, Salah Eddin; Rezaei, Omid; Armoon, Bahram
2018-06-07
According to latest available data there are more of 300,000 people injects drug users (PWID) in Iran. In this study, we used a Blinder-Oaxaca (BO) decomposition to explore the relative contributions of inequality in utilization of NSPs and to decompose it to its determinants in Teheran. We used data from a cross-sectional survey using snowball sampling to recruit 500 PWID from June to July 2016 in Tehran. Participants were reported injecting drug use in the past month, were able to speak and comprehend Farsi enough to respond to survey questions, and were able to provide informed consent to complete the interview. We used a BO method to decompose the role of economic inequality on utilization of needle and syringe programs. A total 520 of clients participated in the study of which data was fully complete for 500. The selected predictor variables (age, education level, marital status, homelessness, HIV risk perception, and HIV knowledge) together explain 54% (8.5% out of 16%) of total inequality in utilization of needle and syringe programs and the remaining 46% constitute the unexplained residual. HIV risk perception status contributed about 38% (3.3% out of 8.5%) to the total health inequality, followed by HIV knowledge (26%) and education level were contributed 20% each, respectively. The results showed that contribution of economic inequalities in utilization of NSPs was primarily explained by the differential effects of HIV risk perception and HIV knowledge among PWID. Reducing HIV risk perception and increasing HIV knowledge might be essential to efforts to eliminate inequalities in access to NSPs among PWID.
2017-01-01
Background Condom failure has always been found to coexist with condom usage, especially among sex workers. Objective To describe the actions of female sex workers when they are faced with situations of condom failure. Methods Using the survey design, the participants were selected through the snowball sampling method. Their responses were obtained using a structured questionnaire. A total of 100 questionnaires were analysed. Results With respect to the immediate actions of sex workers after condom failure, 36% of the respondents continued with the sexual encounter after noticing that the condom was broken. Another 36% stopped immediately when they noticed that the condom had failed, but replaced the condom; 13% of the participants stopped the sexual encounter completely; 3% applied vaginal spermicidal foam; and 5% of the respondents stopped immediately and took a douche when they had the chance. For the actions within the next 24 hours of experiencing condom failure with a client, 53% of the participants did nothing; 4% sought counsel from a professional; 3% of the respondents took alcohol or drugs to forget the incident, 25% went to the clinic for assistance and 8% offered other responses. Conclusion While continuing the sexual encounter without replacing the condom, taking alcohol and drugs or doing nothing could increase the risk of contracting HIV; however, actions like stopping the sexual encounter completely and visiting a clinic or a professional could make a difference between staying HIV negative or seroconverting. There is a need for targeted intervention to address issues of inappropriate behaviours after experiencing condom failure. PMID:29568633
Tian, T; Cai, A J; Huang, B X; Abidan, Ainiwaer; Wang, H; Dai, J H
2017-01-10
Objective: To understand the human papilloma virus (HPV) infection status in men who have sex with men (MSM) recruited from gay bathhouses and HIV voluntary counseling and testing (VCT) clinics in Urumqi, Xinjiang Uygur autonomous region, and identify the associated risk factors. Methods: A total of 200 MSM aged ≥18 years were recruited by using the " snowballing" sampling method from gay bathhouses and VCT clinics in Urumqi during March-May, 2016. The MSM recruited completed questionnaires after filling in the informed consent form. The information about their demographic characteristics and sexual behaviors were collected, and anal swabs were collected from them for HPV genotyping. Results: The overall HPV infection rate was 54.0 % . The HPV infection rate was 66.7 % (74/111) in MSM from gay bathhouses and 38.2 % (34/89) in MSM from VCT clinics and the high risk type HPV infection rate was 39.6 % (44/111) in MSM from gay bathhouses and 14.6 % (13/89) in MSM from VCT clinics, the differences were significant ( χ (2)=16.112, P <0.05; χ (2)=15.190, P <0.05). Multiple logistic regression analysis indicated that the major risk factors for HPV infection included activity in gay bathhouse ( OR =3.732, 95 % CI : 1.950-7.141) and anal sexual behavior ( OR =2.555, 95 %CI : 1.329-4.912). Conclusion: The prevalence of HPV in MSM from gay bathhouses was higher than that in MSM from VCT clinics, indicating that close attention should be paid to the behavior intervention in MSM.
Wang, Yi; Li, Liu-Lin; Zhang, Guong-Gui; Fan, Jing; Zhao, Xi-He; Li, Ke
2012-10-01
To understand the intention on marriage and the related influence factors among men who have sex with men (MSM). Using the snowball sampling method, an anonymous questionnaire survey was achieved by recruiting MSM. A total number of 308 people were included in this survey, the numbers of 'planning to get married' was 34.4%, intended not to get married accounted for 65.6%; and the average age of intending to marry was (28.1 ± 3.3) years old. The intended marriage partners were ordinary women accounted for 83.8%, while another 16.2% were lesbians. Reasons for getting married were under social pressure (65.1%), under family pressure (12.3%), and under personal desire (22.6%). Those who intended to remain contact with gay after marriage accounted for 66.7%, with 16.2% did not and those were not sure accounted for 17.1%. Using the multivariate analysis method, results showed that the independent factors for intention of marriage were: age, sexual orientation, registration for residency, cumulative numbers of regular sexual partners, number of anal sex in the last week, proportion of intention to get married was relatively low among those who were over 35 years of age and their residence of registration were in the city. However those who were bisexual, with uncertain sexual orientation, and with low cumulative numbers of regular sexual partners as well as less anal sex in the past week, occupied higher proportions. MSM population under our current study showed a high percentage on marriage intention which posed serious challenges to the society and families. AIDS prevention on this population seemed to be impacted by demographic characteristics and sexual behavior.
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.
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.
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.
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.
[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.
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…
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.
Noroozi, Mehdi; Sharifi, Hamid; Noroozi, Alireza; Rezaei, Fatemah; Bazrafshan, Mohammad Rafi; Armoon, Bahram
2017-01-01
To our knowledge, no previous study has systematically assessed the role of economic status in risky sexual behavior among people who inject drugs (PWID) in Iran. In this study, we used Blinder-Oaxaca (BO) decomposition to explore the contribution of economic status to inequality in unprotected sex among PWID in Tehran and to decompose it into its determinants. Behavioral surveys among PWID were conducted in Tehran, the capital city of Iran, from November 2016 to April 2017. We employed a cross-sectional design and snowball sampling methodology. We constructed the asset index (weighted by the first principal component analysis factor) using socioeconomic data and then divided the variable into 3 tertiles. We used the BO method to decompose the economic inequality in unprotected sex. Of the 520 recruited individuals, 20 were missing data for variables used to define their economic status, and were therefore excluded from the analysis. Not having access to harm reduction programs was the largest factor contributing to the economic disparity in unprotected sex, accounting for 5.5 percentage points of the 21.4% discrepancy. Of the unadjusted total economic disparity in unprotected sex, 52% was unexplained by observable characteristics included in the regression model. The difference in the prevalence of unprotected sex between the high-income and low-income groups was 25%. Increasing needle syringe program coverage and improving human immunodeficiency virus (HIV) knowledge are essential for efforts to eliminate inequalities in HIV risk behaviors among PWID.
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
Menthol cigarettes and smoking initiation: a tobacco industry perspective
2011-01-01
Objectives To determine what the tobacco industry knew about menthol cigarettes and the initiation of smoking. Methods Based on Food and Drug Administration staff-supplied research questions we used a snowball sampling strategy to search the Legacy Tobacco Documents Library (http://legacy.library.ucsf.edu) between February and April 2010. Of the approximately 11 million documents available in the LTDL, the iterative searches returned tens of thousands of results. Researchers reviewed 2634 documents and 128 were deemed relevant to one or more of the research questions. Results The documents show that menthol is added to cigarettes in part because it is known to be an attractive feature to inexperienced smokers who perceive menthol cigarettes as less harsh and easier to smoke and because of their availability from friends and family. Second, the tobacco industry found that some youths smoke menthols because they perceive them to be less harmful than non-menthol cigarettes. A key product design issue concerns whether to increase brand menthol levels to appeal to the taste preferences of long-term menthol smokers or keep menthol levels lower to appeal to inexperienced smokers. Marketing studies showed that the companies carefully researched the menthol segment of the market in order to recruit younger smokers to their brands. The industry tracked menthol cigarette usage by age, gender and race to inform product development and marketing decisions. Conclusions Menthol is a prominent design feature used by cigarette manufacturers to attract and retain new, younger smokers. PMID:21504927
Surgeons' motivation for choice of workplace.
Kähler, Lena; Kristiansen, Maria; Rudkjøbing, Andreas; Strandberg-Larsen, Martin
2012-09-01
To ensure qualified health care professionals at public hospitals in the future, it is important to understand which factors attract health care professionals to certain positions. The aim of this study was to explore motives for choosing employment at either public or private hospitals in a group of Danish surgeons, as well as to examine if organizational characteristics had an effect on motivation. Eight qualitative interviews were conducted with surgeons from both public and private hospitals sampled using the snowball method. The interviews were based on a semi-structured interview guide and analyzed by means of phenomenological theory. Motivational factors such as personal influence on the job, the opportunity to provide the best possible patient care, challenging work tasks colleagues, and ideological reasons were emphasized by the surgeons as important reasons for their choice of employment. Motivational factors appeared to be strongly connected to the structure of the organization; especially the size of the organization was perceived to be essential. It is worth noting that salary, in contrast to the general belief, was considered a secondary benefit rather than a primary motivational factor for employment. The study revealed that motivational factors are multidimensional and rooted in organizational structure; i.e. organizational size rather than whether the organization is public or private is crucial. There is a need for further research on the topic, but it seems clear that future health care planning may benefit from taking into account the implications that large organizational structures have for the staff working within these organizations. not relevant. not relevant.
First childbirth experience of international marriage migrant women in South Korea.
Chu, Min Sun; Park, Minna; Kim, Jung A
2017-08-01
Since the mid-1990s, a large number of foreign women have migrated from developing countries to South Korea by means of international marriages. These nulliparous foreign women may experience more difficulties in pregnancy and childbirth than native Koreans. This study aimed to describe the meaning of the first childbirth experiences of international marriage migrant women marrying Korean men in South Korea. This is a descriptive phenomenological study that included 10 participants using the purposive and snowball sampling in one multicultural support center in Seoul, South Korea. Colaizzi's data analysis method was used to inductively determine themes and formulate meanings. The meanings of first childbirth were categorized into four themes-'coming to a crisis,' 'depending on others,' 'searching for solutions,' and 'strengthening family unity.' Inadequate antenatal care is associated with obstacles such as language barriers, social isolation, lack of knowledge, different midwifery practice and dependent lifestyle. Meanwhile, their children were a source of energy for the women to fulfill their emotional needs and improve family relationships. Childbirth is a life-changing event for these women, in which they face challenges as well as opportunities to develop new coping skills and a new role identity in their family. It is important for healthcare providers and policy makers to identify obstacles and unmet needs to improve maternity care in light of the distinctive challenges of immigrant living in multicultural families. Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.
Creating an advance-care-planning decision aid for high-risk surgery: a qualitative study
2014-01-01
Background High-risk surgery patients may lose decision-making capacity as a result of surgical complications. Advance care planning prior to surgery may be beneficial, but remains controversial and is hindered by a lack of appropriate decision aids. This study sought to examine stakeholders’ views on the appropriateness of using decision aids, in general, to support advance care planning among high-risk surgery populations and the design of such a decision aid. Methods Key informants were recruited through purposive and snowball sampling. Semi-structured interviews were conducted by phone until data collected reached theoretical saturation. Key informants were asked to discuss their thoughts about advance care planning and interventions to support advance care planning, particularly for this population. Researchers took de-identified notes that were analyzed for emerging concordant, discordant, and recurrent themes using interpretative phenomenological analysis. Results Key informants described the importance of initiating advance care planning preoperatively, despite potential challenges present in surgical settings. In general, decision aids were viewed as an appropriate approach to support advance care planning for this population. A recipe emerged from the data that outlines tools, ingredients, and tips for success that are needed to design an advance care planning decision aid for high-risk surgical settings. Conclusions Stakeholders supported incorporating advance care planning in high-risk surgical settings and endorsed the appropriateness of using decision aids to do so. Findings will inform the next stages of developing the first advance care planning decision aid for high-risk surgery patients. PMID:25067908
Resident Autonomy in the Operating Room: How Faculty Assess Real-time Entrustability.
Chen, Xiaodong Phoenix; Sullivan, Amy M; Smink, Douglas S; Alseidi, Adnan; Bengtson, Joan M; Kwakye, Gifty; Dalrymple, John L
2018-02-20
This study aimed to identify the empirical processes and evidence that expert surgical teachers use to determine whether to take over certain steps or entrust the resident with autonomy to proceed during an operation. Assessing real-time entrustability is inherent in attending surgeons' determinations of residents' intraoperative autonomy in the operating room. To promote residents' autonomy, it is necessary to understand how attending surgeons evaluate residents' performance and support opportunities for independent practice based on the assessment of their entrustability. We conducted qualitative semi-structured interviews with 43 expert surgical teachers from 21 institutions across 4 regions of the United States, using purposeful and snowball sampling. Participants represented a range of program types, program size, and clinical expertise. We applied the Framework Method of content analysis to iteratively analyze interview transcripts and identify emergent themes. We identified a 3-phase process used by most expert surgical teachers in determining whether to take over intraoperatively or entrust the resident to proceed, including 1) monitoring performance and "red flags," 2) assessing entrustability, and 3) granting autonomy. Factors associated with individual surgeons (eg, level of comfort, experience, leadership role) and the context (eg, patient safety, case, and time) influenced expert surgical teachers' determinations of entrustability and residents' final autonomy. Expert surgical teachers' 3-phase process of decisions on take-over provides a potential framework that may help surgeons identify appropriate opportunities to develop residents' progressive autonomy by engaging the resident in the determination of entrustability before deciding to take over.
Tan, Christine Liang Hoay; Hassali, Mohamed Azmi; Saleem, Fahad; Shafie, Asrul Akmal; Aljadhay, Hisham; Gan, Vincent B Y
2016-12-01
To improve pharmaceutical care delivery in Malaysia, the Ministry of Health (MOH) had introduced the concept of value added services (VAS). Despite its reported convenience and advantages, VAS utilization rate is low in the country. The study aims to explore patients' understanding, beliefs and expectations towards VAS in Malaysia using the theory of planned behaviour (TPB) as the theoretical model. A qualitative methodology was used whereby face-to-face interviews were conducted with 12 patients who collected partial medicine supplies from government pharmacies. Participants were recruited using purposive and snowball sampling method in the state of Negeri Sembilan, Malaysia. Interviews were audio-recorded. Verbatim transcription and thematic content analysis were performed on the data. Thematic content analysis yielded five major themes: (i) attitudes towards using VAS, (ii) subjective norms, (iii) perceived behavioural control, (iv) lack of knowledge and understanding of VAS and (v) expectations towards VAS. The interviews explored and informed new information about salient beliefs towards pharmacy VAS. The findings suggest that VAS is still in its infancy and a more robust and effective advertising and marketing campaign is needed to boost the adoption rate. Behavioural attitudes, subjective norms and perceived control elements were discussed and serve as important variables of interest in future study. Expectations towards VAS serve as an important guideline to further improve patient-oriented services. © 2015 The Authors. Health Expectations Published by John Wiley & Sons Ltd.
Lee, Iyn-Hyang; Rhie, Sandy Jeong; Je, Nam Kyung; Rhew, Ki Yon; Ji, Eunhee; Oh, Jung Mi; Lee, Euni; Yoon, Jeong-Hyun
2016-10-01
Purpose To explore the need for pharmaceutical care services, key features of desirable pharmacy services, and perceived barriers for advancing the services in hospital environments with doctors and nurses who are key co-workers of the interdisciplinary team care services.Methods Semi-structured, in-depth interviews with eighteen doctors and fifteen nurses employing purposive and snowballing sampling strategies were conducted in ten hospitals in South Korea. Results The level of pharmaceutical care was varied across regions or institutions in South Korea. The concept of pharmaceutical care was insufficiently defined, and tended to be limited to some parts of medication counseling. Through pharmaceutical care services, doctors desired to acquire comprehensive drug information from and to share clinical responsibilities with pharmacists. Nurses wished to lower their burdens of medication counseling services from their daily practices. Doctors and nurses asked for pharmacists providing essential and carefully selected medication information to their patients in a patient-centered manner. The listed barriers to pharmaceutical care included the lack of appropriate systems for reward, insufficient accessibility to patient records by pharmacists, ambiguous role descriptions of pharmacist, and absence of effective communication among professionals. Conclusion A successful pharmaceutical care service model should allow efficient exchange of information among healthcare professionals to build inter-professional trust and to provide a continuity of care both in terms of time and setting. As prerequisites of such system, it was warranted to develop clinical evidence and an appropriate reward system for pharmaceutical care services.
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.
The impact of an indigenous proverb on women's mental health: A phenomenological approach.
Phiri, Seepaneng S; Mulaudzi, Fhumulani M; Heyns, Tanya
2015-11-23
Proverbs and idioms represent cultural and societal beliefs and values inherited from the forefathers. An example is lebitla la mosadi ke bogadi. Over many decades African people have used such ancient instructions to counsel women to be resilient in their marriages thus impacting on their mental health. The purpose of this article was to explore and describe that proverb and its impact on women's mental health. Hermeneutic phenomenology was used to explore and describe the prover band its impact on indigenous women's mental health. The population included married, divorced, widowed and single women who were attending social clubs or networks in the cities of Tshwane and Johannesburg. Snowball and purposive sampling was used to select 57 participants. Five face-to-face interviews and eight focus groups interviews were conducted. Colaizzi's data analysis method was used to analyse data. Oppression and stigmatisation of women and their families and harmful effects that may result in death were identified as having an impact on women's mental health. Some women shared that they were oppressed in many ways. In addition, they feared stigmatisation should they wish to divorce. They constantly lived in fear of being harmed or killed by their spouses. There was a need for nurses to develop awareness regarding cultural issues so that women are better served in primary healthcare settings. Women who are suspected of experiencing abuse, should be screened for abuse so that they can be assisted accordingly.
Impact of Intervention to Improve Nursing Home Resident-Staff Interactions and Engagement.
Hartmann, Christine W; Mills, Whitney L; Pimentel, Camilla B; Palmer, Jennifer A; Allen, Rebecca S; Zhao, Shibei; Wewiorski, Nancy J; Sullivan, Jennifer L; Dillon, Kristen; Clark, Valerie; Berlowitz, Dan R; Snow, Andrea Lynn
2018-04-30
For nursing home residents, positive interactions with staff and engagement in daily life contribute meaningfully to quality of life. We sought to improve these aspects of person-centered care in an opportunistic snowball sample of six Veterans Health Administration nursing homes (e.g., Community Living Centers-CLCs) using an intervention that targeted staff behavior change, focusing on improving interactions between residents and staff and thereby ultimately aiming to improve resident engagement. We grounded this mixed-methods study in the Capability, Opportunity, Motivation, Behavior (COM-B) model of behavior change. We implemented the intervention by (a) using a set of evidence-based practices for implementing quality improvement and (b) combining primarily CLC-based staff facilitation with some researcher-led facilitation. Validated resident and staff surveys and structured observations collected pre and post intervention, as well as semi-structured staff interviews conducted post intervention, helped assess intervention success. Sixty-two CLC residents and 308 staff members responded to the surveys. Researchers conducted 1,490 discrete observations. Intervention implementation was associated with increased staff communication with residents during the provision of direct care and decreased negative staff interactions with residents. In the 66 interviews, staff consistently credited the intervention with helping them (a) develop awareness of the importance of identifying opportunities for engagement and (b) act to improve the quality of interactions between residents and staff. The intervention proved feasible and influenced staff to make simple enhancements to their behaviors that improved resident-staff interactions and staff-assessed resident engagement.
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
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
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.
Cai, Y M; Song, Y J; Liu, H; Hong, F C
2017-11-06
Objective: To investigate the factors associated with syphilis/HIV infection among men who have sex with men (MSM) maintaining a single sexual partner in Shenzhen. Methods: Respondent driven sampling and snowball sampling method were used to recruit MSM receiving voluntary counseling and testing in Shenzhen Rainbow clinic from 2011 to 2016. aged 18 years and above; reported having one or more anal sexual partners in the recent 6 months. A total of 3 109 men who have sex with men (MSM) were involved in the study. Questionnaire-based interviews were conducted on a one-on-one basis. Data were collected including socio-demographic information, human immunodeficiency virus (HIV) testing history, history of blood donation and drug abuse in the recent two years, self-identified sexual orientation, role in homosexual behavior, ever being money boys (MB) and clients of MB, female sexual partners in the recent 6 months. 5 ml blood samples were taken after questionnaires. Syphilis was screened using toluidine red unheated serum test for the antibody of treponema pallidum and then confirmed by treponema pallidum particle assay. The enzyme-linked immunosorbent assay (ELISA) was used for screening HIV and western blot was used to confirm the HIV screening results. The difference of condom use among MSM between female sexual partners and male sexual partners were compared. Multivariate unconditional stepwise logistic regression model was used to analyze factors associated with syphilis infection and HIV positive among MSM. Results: A total of 3 109 eligible participants with mean (SD) age of 31.49 (8.64) years were enrolled in this study. Among them, 565 cases were infected with syphilis (18.17%), 330 cases were infected with HIV (10.61%), and 165 cases (5.31%) were syphilis co-infected with HIV. 791 (25.44%) reported maintaining a single sexual partners in the recent 6 months. Compared to MSM with multiple sexual partners, the prevalence of syphilis and HIV infection among MSM with a single sexual partner were lower, and the OR (95% CI ) were 0.64 (0.51-0.81) and 0.66 (0.49-0.90), respectively. Conclusion: The proportion of fixed single sexual partner was much lower among MSM in Shenzhen. Maintaining a single sexual partners can reduce the risk of syphilis/HIV infection among MSM.
Manchaiah, Vinaya; Danermark, Berth; Ahmadi, Tayebeh; Tomé, David; Zhao, Fei; Li, Qiang; Krishna, Rajalakshmi; Germundsson, Per
2015-01-01
Background Hearing loss is one of the most common chronic conditions in older adults. In audiology literature, several studies have examined the attitudes and behavior of people with hearing loss; however, not much is known about the manner in which society in general views and perceives hearing loss. This exploratory study was aimed at understanding the social representation of hearing loss (among the general public) in the countries of India, Iran, Portugal, and the UK. We also compared these social representations. Materials and methods The study involved a cross-sectional design, and participants were recruited using the snowball sampling method. A total of 404 people from four countries participated in the study. Data were collected using a free-association task where participants were asked to produce up to five words or phrases that came to mind while thinking about hearing loss. In addition, they were also asked to indicate if each word they presented had positive, neutral, or negative associations in their view. Data were analyzed using various qualitative and quantitative methods. Results The most frequently occurring categories were: assessment and management; causes of hearing loss; communication difficulties; disability; hearing ability or disability; hearing instruments; negative mental state; the attitudes of others; and sound and acoustics of the environment. Some categories were reported with similar frequency in most countries (eg, causes of hearing loss, communication difficulties, and negative mental state), whereas others differed among countries. Participants in India reported significantly more positive and fewer negative associations when compared to participants from Iran, Portugal, and the UK. However, there was no statistical difference among neutral responses reported among these countries. Also, more differences were noted among these countries than similarities. Conclusion These findings provide useful insights into the public perception of hearing loss that may prove useful in public education and counseling. PMID:26604726
van Limburg, Maarten; Wentzel, Jobke; Sanderman, Robbert; van Gemert-Pijnen, Lisette
2015-08-13
It is acknowledged that the success and uptake of eHealth improve with the involvement of users and stakeholders to make technology reflect their needs. Involving stakeholders in implementation research is thus a crucial element in developing eHealth technology. Business modeling is an approach to guide implementation research for eHealth. Stakeholders are involved in business modeling by identifying relevant stakeholders, conducting value co-creation dialogs, and co-creating a business model. Because implementation activities are often underestimated as a crucial step while developing eHealth, comprehensive and applicable approaches geared toward business modeling in eHealth are scarce. This paper demonstrates the potential of several stakeholder-oriented analysis methods and their practical application was demonstrated using Infectionmanager as an example case. In this paper, we aim to demonstrate how business modeling, with the focus on stakeholder involvement, is used to co-create an eHealth implementation. We divided business modeling in 4 main research steps. As part of stakeholder identification, we performed literature scans, expert recommendations, and snowball sampling (Step 1). For stakeholder analyzes, we performed "basic stakeholder analysis," stakeholder salience, and ranking/analytic hierarchy process (Step 2). For value co-creation dialogs, we performed a process analysis and stakeholder interviews based on the business model canvas (Step 3). Finally, for business model generation, we combined all findings into the business model canvas (Step 4). Based on the applied methods, we synthesized a step-by-step guide for business modeling with stakeholder-oriented analysis methods that we consider suitable for implementing eHealth. The step-by-step guide for business modeling with stakeholder involvement enables eHealth researchers to apply a systematic and multidisciplinary, co-creative approach for implementing eHealth. Business modeling becomes an active part in the entire development process of eHealth and starts an early focus on implementation, in which stakeholders help to co-create the basis necessary for a satisfying success and uptake of the eHealth technology.
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.
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
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.
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.
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.
[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..
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.
Ecosystem thresholds in Lake Kälksjön, Sweden, in response to rapid climate cooling 8200 years ago
NASA Astrophysics Data System (ADS)
Randsalu Wendrup, Linda; Conley, Daniel J.; Hammarlund, Dan; Snowball, Ian; Carstensen, Jacob; Fritz, Sherilyn C.
2010-05-01
Commonly, ecosystems are thought to show a smooth response in relation to gradually changing conditions, shifting over long periods of time from one state to another, thus reflecting the continuum of change along environmental gradients for each set of conditions. The theoretical concept that ecosystems can experience regime shifts and shift abruptly from one state to another, producing changes in dominance of organisms and overall ecosystem behaviour has, however, existed for more than 30 years. The theory has been further developed and it has been demonstrated, in a number of different terrestrial, freshwater and marine systems, that ecosystems stressed by human or climate perturbations can undergo drastic changes, first reaching an ecological threshold and then switching abruptly to an alternative state. The study of regime shifts in lakes as a result of climate change is complicated because lake biota and processes depend not only on regional climate changes but also on changes in the lake catchment and processes within the lake. Many factors in a lake will respond simultaneously and differently to the effects of climate change, resulting in complex synergy within the aquatic environment. Nevertheless we want to bring together concepts generated in contemporary ecological studies to study and test hypotheses regarding sudden mode shifts and ecological reorganisations in lakes using paleoecological methods, using diatom and numerical analyses as the main analytical tools. We are investigating how lakes respond to climate, during periods of both cooling and warming, identifying thresholds at which regime shifts occur and trying to develop numerical methods to test for regime shifts in paleoecological data. Here we present the preliminary results from a study of the ecosystem response to the "8.2 ka cold event" in Lake Kälksjön in west central Sweden. The lake is annually laminated (varved) and a series of nine radiocarbon measurements obtained at increments of 50 years have been used to wiggle match the sediments to the tree-ring derived radiocarbon calibration curve (Snowball et al., in press). Snowball et al. (in press) used the wiggle matching, organic carbon measurements, mineral magnetic parameters and XRF data and reconstructed a distinct period of enhanced erosion in the catchment from 8066±25 to 7920±25 cal. yr BP. Their results suggest that an abrupt onset of winter precipitation in west-central Sweden started at least 50 years after the onset of the "8.2 kyr cold event" as defined by oxygen isotope data from Greenland. The lake has been sampled for diatom analysis at increments of 10 years over 500 years covering the 8.2 event. The wiggle matched chronology and presence of varves allows for a high resolution time constrained diatom analysis which we hope will reveal the response of the ecosystem to the rapid cooling and also allow us to work on developing and testing numerical methods for detecting and analysing regime shifts. A preliminary low resolution diatom study shows that the diatom flora displays a benthic response to the climate cooling. It also shows that the diatoms seem to react earlier than the previously measured parameters, suggesting that the diatoms and the lake ecosystem are affected by the rapid cooling rather immediately, for example due to changes in ice cover duration, while increased winter precipitation affects the ecosystem at a later stage.
Dodd, Warren; Humphries, Sally; Patel, Kirit; Majowicz, Shannon; Little, Matthew; Dewey, Cate
2017-09-12
Internal labour migration is an important and necessary livelihood strategy for millions of individuals and households in India. However, the precarious position of migrant workers within Indian society may have consequences for the health of these individuals. Previous research on the connections between health and labour mobility within India have primarily focused on the negative health outcomes associated with this practice. Thus, there is a need to better identify the determinants of internal migrant health and how these determinants shape migrant health outcomes. An exploratory mixed methods study was conducted in 26 villages in the Krishnagiri district of Tamil Nadu. Sixty-six semi-structured interviews were completed using snowball sampling, followed by 300 household surveys using multi-stage random sampling. For qualitative data, an analysis of themes and content was completed. For quantitative data, information on current participation in internal labour migration, in addition to self-reported morbidity and determinants of internal migrant health, was collected. Morbidity categories were compared between migrant and non-migrant adults (age 14-65 years) using a Fisher's exact test. Of the 300 households surveyed, 137 households (45.7%) had at least one current migrant member, with 205 migrant and 1012 non-migrant adults (age 14-65 years) included in this study. The health profile of migrant and non-migrants was similar in this setting, with 53 migrants (25.9%) currently suffering from a health problem compared to 273 non-migrants (27.0%). Migrant households identified both occupational and livelihood factors that contributed to changes in the health of their migrant members. These determinants of internal migrant health were corroborated and further expanded on through the semi-structured interviews. Internal labour migration in and of itself is not a determinant of health, as participation in labour mobility can contribute to an improvement in health, a decline in health, or no change in health among migrant workers. Targeted public health interventions should focus on addressing the determinants of internal migrant health to enhance the contributions these individuals can make to their households and villages of origin.
2012-01-01
Background Researchers are increasingly recognizing the importance of addressing sexual and drug-related HIV risk within the context of intimate relationships rather than solely focusing on individual behaviors. Practical and effective methods are needed to recruit, screen, and enroll the high risk and hard-to-reach couples who would most benefit from HIV interventions, such as drug-using female sex workers (FSWs) and their intimate, non-commercial partners. This paper outlines a bi-national, multidisciplinary effort to develop and implement a study protocol for research on the social context and epidemiology of HIV, sexually transmitted infections (STI), and high risk behaviors among FSWs and their non-commercial male partners in Tijuana and Ciudad Juarez, Mexico. We provide an overview of our study and specifically focus on the sampling, recruitment, screening, and successful enrollment of high risk couples into a public health study in this context. Methods/Design We used targeted and snowball sampling to recruit couples through the female partner first and administered a primary screener to check her initial eligibility. Willing and eligible females then invited their primary male partners for couple-based screening using a couple verification screening (CVS) instrument adapted from previous studies. The CVS rechecked eligibility and separately asked each partner the same questions about their relationship to "test" if the couple was legitimate. We adapted the original protocol to consider issues of gender and power within the local cultural and socioeconomic context and expanded the question pool to create multiple versions of the CVS that were randomly administered to potential couples to determine eligibility and facilitate study enrollment. Discussion The protocol successfully enrolled 214 high risk couples into a multi-site public health study. This work suggests the importance of collaborating to construct a study protocol, understanding the local population and context, and drawing on multiple sources of input to determine eligibility and verify the legitimacy of relationships. We provide a practical set of tools that other researchers should find helpful in the study of high risk couples in international settings, with particular relevance to studies of FSWs and their intimate partners. PMID:22348625
van Woezik, Anne F G; Braakman-Jansen, Louise M A; Kulyk, Olga; Siemons, Liseth; van Gemert-Pijnen, Julia E W C
2016-01-01
Infection prevention and control can be seen as a wicked public health problem as there is no consensus regarding problem definition and solution, multiple stakeholders with different needs and values are involved, and there is no clear end-point of the problem-solving process. Co-creation with stakeholders has been proposed as a suitable strategy to tackle wicked problems, yet little information and no clear step-by-step guide exist on how to do this. The objectives of this study were to develop a guideline to assist developers in tackling wicked problems using co-creation with stakeholders, and to apply this guideline to practice with an example case in the field of infection prevention and control. A mixed-method approach consisting of the integration of both quantitative and qualitative research was used. Relevant stakeholders from the veterinary, human health, and public health sectors were identified using a literature scan, expert recommendations, and snowball sampling. The stakeholder salience approach was used to select key stakeholders based on 3 attributes: power, legitimacy, and urgency. Key values of stakeholders (N = 20) were derived by qualitative semi-structured interviews and quantitatively weighted and prioritized using an online survey. Our method showed that stakeholder identification and analysis are prerequisites for understanding the complex stakeholder network that characterizes wicked problems. A total of 73 stakeholders were identified of which 36 were selected as potential key stakeholders, and only one was seen as a definite stakeholder. In addition, deriving key stakeholder values is a necessity to gain insights into different problem definitions, solutions and needs stakeholders have regarding the wicked problem. Based on the methods used, we developed a step-by-step guideline for co-creation with stakeholders when tackling wicked problems. The mixed-methods guideline presented here provides a systematic, transparent method to identify, analyze, and co-create with stakeholders, and to recognize and prioritize their values, problem definitions, and solutions in the context of wicked problems. This guideline consists of a general framework and although it was applied in an eHealth context, may be relevant outside of eHealth as well.
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.
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.
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.
Berwald, Sharne; Roche, Moïse; Adelman, Simon; Mukadam, Naaheed; Livingston, Gill
2016-01-01
Objectives We aimed to identify and explore the barriers to help-seeking for memory problems, specifically within UK Black African and Caribbean communities. Method We purposively recruited participants from community groups and subsequent snowball sampling, to achieve a maximum variation sample and employed thematic analysis. Our qualitative semi-structured interviews used a vignette portraying a person with symptoms of dementia, and we asked what they or their family should do. We stopped recruiting when no new themes were arising. Results and significance We recruited 50 people from a range of age groups, country of origin, time in the UK, religion and socio-economic background. Some of the barriers to presentation with dementia have been reported before, but others were specific to this group and newly identified. Many people recognised forgetfulness but neither that it could be indicative of dementia, nor the concept of dementia as applying to them. Dementia was viewed as a white person’s illness. Participants felt there was little point in consulting a doctor for forgetfulness. Many thought that seeing a GP was only for severe problems. Some said that their culture was secretive and highly valued privacy of personal affairs and therefore did not want to discuss what they regarded as a private and stigmatising problem with a GP. Participants did not appreciate their GP could refer to memory services who have more time and expertise. They were concerned about harm from medication and compulsory institutionalisation. Care should be from the family. Any intervention should emphasise the legitimacy of seeing a doctor early for memory concerns, that dementia is a physical illness which also occurs in the Black community, that help and time are available from memory services whose role is to prolong independence and support families in caring. PMID:27045999
A Survey of Occupational Therapy Practice in Beijing, China.
Shi, Yun; Howe, Tsu-Hsin
2016-06-01
There is an increasing demand for rehabilitation services in China as a result of the growing number of people with physical and mental challenges, as well as the growing population of older adults. The purpose of this study was to explore the current occupational therapy (OT) resources available in Beijing, China, to serve as the first step in planning the response to increasing demand for OT services from the people of China. Specifically, using the snowball sampling survey method, we explored the work practice, including years of working experience, work setting, weekly work hours, annual income and factors related to job satisfaction among occupational therapists in Beijing, China. A total of 44 occupational therapists currently working in the Beijing area responded to our survey. The results demonstrated that most of the therapists working in Beijing area were young and inexperienced. Despite the fact that the participants had an average age of 31 years old and an average of 8 years' working experience, 61.4% of therapists were under 30 years old and more than half of therapists had less than 5 years of OT experiences. Among those included in the study sample, 50% had earned degrees in OT, and the rest of the OT personnel received OT-related on-the-job training in various forms and lengths of time. A majority of the participants worked in hospital settings with adults or children with physical disabilities and used therapeutic activities and therapeutic exercises. Being an occupational therapist is not a high-paying job. Education satisfaction, work experience and annual income are the factors related to job satisfaction for the participants. The majority of occupational therapists expressed the need to receive more support for clinical-related trainings. We plan to expand this pilot study nationwide to gain an in-depth and comprehensive understanding of the OT workforce in China. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Kirwan, Amy; Quinn, Brendan; Winter, Rebecca; Kinner, Stuart A; Dietze, Paul; Stoové, Mark
2015-08-04
Injecting drug use (IDU) is a strong predictor of recidivism and re-incarceration in ex-prisoners. Although the links between drug use and crime are well documented, studies examining post-release criminal activity and re-incarceration risk among ex-prisoners with a history of IDU are limited. We aimed to explore factors associated with property crime among people with a history of IDU recently released from prison. Individuals with a history of IDU released from prison within the past month were recruited via targeted and snowball sampling methods from street drug markets and services for people who inject drugs (PWID) into a 6-month cohort study. A multivariate logistic regression analysis of baseline data identified adjusted associations with self-reported property crime soon after release. Interviews were conducted a median of 23 days post-release with 141 participants. Twenty-eight percent reported property crime in this period and 85% had injected drugs since release. Twenty-three percent reported injecting at least daily. Reporting daily injecting (adjusted odds ratio (aOR) 4.36; 95% confidence interval (CI) = 1.45-13.07), illicit benzodiazepine use (aOR = 2.59; 95% CI = 1.02-5.67), being arrested (aOR = 6.12; 95% CI = 1.83-20.45) and contact with mental health services (aOR = 4.27; 95% CI = 1.45-12.60) since release were associated with property crime. Criminal activity soon after release was common in this sample of PWID, underscoring the need for improved pre-release, transitional and post-release drug use dependence and prevention programmes. Addressing co-occurring mental disorder and poly-pharmaceutical misuse among those with a history of IDU in prison, and during the transition to the community, may reduce property crime in this group.
Budambula, Valentine; Matoka, Charles; Ouma, James; Ahmed, Aabid A; Otieno, Michael F; Were, Tom
2018-01-30
Substance use is increasingly becoming prevalent on the African continent, fueling the spread of HIV infection. Although socio-demographic factors influence substance consumption and risk of HIV infection, the association of these factors with HIV infection is poorly understood among substance users on the African continent. The objective of the study was to assess socio-demographic and sexual practices that are associated with HIV infection among injection drug users (IDUs), non-IDUs, and non-drug users (DUs) at an urban setting of coastal Kenya. A cross-sectional descriptive study was conducted among 451 adults comprising HIV-infected and -uninfected IDUs (n = 157 and 39); non-IDUs (n = 17 and 48); and non-DUs (n = 55 and 135); respectively at coastal, Kenya. Respondent driven sampling, snowball and makeshift methods were used to enroll IDUs and non-IDUs. Convenience and purposive sampling were used to enroll non-DUs from the hospital's voluntary HIV testing unit. Participant assisted questionnaire was used in collecting socio-demographic data and sexual practices. Binary logistic regression analysis indicated that higher likelihood of HIV infection was associated with sex for police protection (OR, 9.526; 95% CI, 1.156-78.528; P = 0.036) and history of sexually transmitted infection (OR, 5.117; 95% CI, 1.924-13.485; P = 0.001) in IDUs; divorced, separated or widowed marital status (OR, 6.315; 95% CI, 1.334-29.898; P = 0.020) in non-IDUs; and unemployment (OR, 2.724; 95% CI, 1.049-7.070; P = 0.040) in non-drug users. However, never married (single) marital status (OR, 0.140; 95% CI, 0.030-0.649; P = 0.012) was associated with lower odds for HIV infection in non-drug users. Altogether, these results suggest that socio-demographic and sexual risk factors for HIV transmission differ with drug use status, suggesting targeted preventive measures for drug users.
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
Chaves, Paula; Simões, Daniela; Paço, Maria; Pinho, Francisco; Duarte, José Alberto; Ribeiro, Fernando
2017-12-01
Deep friction massage is one of several physiotherapy interventions suggested for the management of tendinopathy. To determine the prevalence of deep friction massage use in clinical practice, to characterize the application parameters used by physiotherapists, and to identify empirical model-based patterns of deep friction massage application in degenerative tendinopathy. observational, analytical, cross-sectional and national web-based survey. 478 physiotherapists were selected through snow-ball sampling method. The participants completed an online questionnaire about personal and professional characteristics as well as specific questions regarding the use of deep friction massage. Characterization of deep friction massage parameters used by physiotherapists were presented as counts and proportions. Latent class analysis was used to identify the empirical model-based patterns. Crude and adjusted odds ratios and 95% confidence intervals were computed. The use of deep friction massage was reported by 88.1% of the participants; tendinopathy was the clinical condition where it was most frequently used (84.9%) and, from these, 55.9% reported its use in degenerative tendinopathy. The "duration of application" parameters in chronic phase and "frequency of application" in acute and chronic phases are those that diverge most from those recommended by the author of deep friction massage. We found a high prevalence of deep friction massage use, namely in degenerative tendinopathy. Our results have shown that the application parameters are heterogeneous and diverse. This is reflected by the identification of two application patterns, although none is in complete agreement with Cyriax's description. Copyright © 2017 Elsevier Ltd. All rights reserved.
VAARTSTRA, MATTHEW B.; KERCHER, VANESSA M.; START, AMANDA; BROWN, AMBER N.; PETERSON, MARK D.; MCGRATH, RYAN
2017-01-01
Understanding factors that contribute to a student’s selection of an exercise science-related major is important to student success, higher education and industry. This study sought to 1) better understand why undergraduate students study an exercise science-related major, 2) determine whether positive influences to study an exercise science-related major differ by academic classification, and 3) identify what student’s aspirations are after graduation. Department administrators from four-year colleges and universities offering an exercise science-related major in the Northwest Region of the United States (i.e., Idaho, Montana, Oregon, and Washington) were contacted. Cooperating department administrators were given self-reported questionnaires for students to complete using a snowball sampling method. A total of 388 participants completed the questionnaire. Interest in the subject and potential job opportunities were the most common reasons to study an exercise science-related major. Self-reported Holland’s codes identified that realistic and social personalities were most prevalent among participants. Seniors rated a friend’s influence and college advisors as stronger influences to study an exercise science-related major compared to freshmen. Pay in the field was a stronger influence for freshmen to study an exercise science-related major than for fifth-year seniors, whereas freshmen were less influenced by introductory courses to study an exercise-science related major than fifth-year seniors. The majority of undergraduate students studying an exercise science-related major planned on attending graduate school after completing their baccalaureate degree. These findings can be used to help guide undeclared students and better serve undergraduates enrolled in an exercise science-related major. PMID:28966716
Jiang, Y; Dou, Y L; Cai, A J; Zhang, Z; Tian, T; Dai, J H; Huang, A L
2016-02-01
Knowledge-motivation-psychological model was set up and tested through structural equation model to provide evidence on HIV prevention related strategy in Men who have Sex with Men (MSM). Snowball sampling method was used to recruit a total of 550 MSM volunteers from two MSM Non-Governmental Organizations in Urumqi, Xinjiang province. HIV prevention related information on MSM was collected through a questionnaire survey. A total of 477 volunteers showed with complete information. HIV prevention related Knowledge-motivation-psychological model was built under related experience and literature. Relations between knowledge, motivation and psychological was studied, using a ' structural equation model' with data from the fitting questionnaires and modification of the model. Structural equation model presented good fitting results. After revising the fitting index: RMSEA was 0.035, NFI was 0.965 and RFI was 0.920. Thereafter the exogenous latent variables would include knowledge, motivation and psychological effects. The endogenous latent variable appeared as prevention related behaviors. The standardized total effects of motivation, knowledge, psychological on prevention behavior were 0.44, 0.41 and 0.17 respectively. Correlation coefficient of motivation and psychological effects was 0.16. Correlation coefficient on knowledge and psychological effects was -0.17 (P<0.05). Correlation coefficient of knowledge and motivation did not show statistical significance. Knowledge of HIV and motivation of HIV prevention did not show any accordance in MSM population. It was necessary to increase the awareness and to improve the motivation of HIV prevention in MSM population.
False promises: The tobacco industry, “low-tar” cigarettes, and older smokers
Cataldo, Janine K.; Malone, Ruth E.
2009-01-01
Objective To investigate the role of the tobacco industry in marketing to and sustaining tobacco addiction among older smokers and aging Baby Boomers. Methods Archival searches of electronic archives of internal tobacco company documents using a snowball sampling approach. Analysis utilizing iterative and comparative review of documents, classification by themes, and a hermeneutic interpretive approach to develop a case study. Results Based on extensive marketing research, tobacco companies aggressively targeted older smokers and sought to prevent them from quitting. Innovative marketing approaches were used. “Low tar” cigarettes were developed in response to the health concerns of older smokers, despite industry knowledge that such products had no health advantage and did not help smokers quit. Conclusion Tobacco industry activities influence the context of cessation for older smokers in several ways. Through marketing “low-tar” or “light” cigarettes to older smokers at risk at quitting, the industry contributes to the illusion that such cigarettes are safer; however, “light” cigarettes may actually make it harder for addicted smokers to quit. Through targeted mailings of coupons and incentives, the industry discourages older smokers from quitting. Through rhetoric aimed at convincing addicted smokers that they alone are responsible for their smoking, the industry contributes to self-blame, a documented barrier to cessation. Educating practitioners, older smokers and families about the tobacco industry’s influence may decrease the tendency to “blame the victim,” thereby enhancing the likelihood of tobacco addiction treatment for older adults. Comprehensive tobacco control measures must include a focus on older smokers. PMID:18691279
Slade, Susan C; Hay-Smith, Jean; Mastwyk, Sally; Morris, Meg E; Frawley, Helena
2018-05-24
The experiences and information needs of clinicians who use pelvic floor muscle training to manage urinary incontinence were explored. Qualitative methods were used to conduct thematic analysis of data collected from clinician focus groups and interviews. Participants were registered physiotherapists and continence nurses in Melbourne, Australia. Recruitment was through a combination of purposive and "snowball" sampling and continued until data adequacy was reached. Twenty-eight physiotherapists and one continence nurse participated in seven focus groups and one interview. The main finding communicated by the participants was that pelvic floor muscle training requires comprehensive descriptions of program details in order for clinicians to implement evidence-based interventions. The following themes were identified: (1) pelvic floor muscle training tailored to the needs of each individual is essential; (2) training-specific cues and verbal prompts assist patients to learn and engage with exercises; and (3) clinicians can benefit from research summaries and reports that provide explicit and comprehensive descriptions and decision rules about intervention content and progression. The data indicated that some clinicians can have difficulty interpreting and applying research findings because it is not always well reported. Clinicians who use pelvic floor muscle training to treat urinary incontinence advised can benefit from accessing explicit details of interventions tested in research and reported as effective. They viewed tailoring therapy to individual goals and the use of verbal prompts and visualization cues as important engagement strategies for effective exercise performance. Explicit reporting could be facilitated by using an exercise guideline template, such as the Consensus on Exercise Reporting Template (CERT). © 2018 Wiley Periodicals, Inc.
Why Abortion is Illegal? Comparison of Legal and Illegal Abortion: A Critical Review.
Huq, M E; Raihan, M J; Shirin, H; Chowdhury, S; Jahan, Y; Chowdhury, A S; Rahman, M M
2017-10-01
Abortion is the termination of pregnancy that occurs spontaneously or purposely. In the most developed world, abortion is legally allowed for women seeking safe termination of pregnancies. Particularly, when access to legal abortion is restricted, abortion is the resort to unsafe methods. The aim of this review is to necessitate safe abortion and to accentuate the consequences of illegal abortion in case of legal prohibition. We used Pubmed, MedLine and Scopus databases to review previous literatures of safe, unsafe, legal and illegal abortions. Research work and reports from organizations such as World Health Organization (WHO), World Bank (WB) and United Nations (UN) were included. Snowball sampling was used to obtain relevant journals. Abortion is conventional whether it is safe, unsafe, legal or illegal. The intention of the antiabortion policy was to reduce the number of abortions globally. However, instead of decreasing rates, evidences show significant increase in abortions. When abortion is legal, the preconditions to be ensured are availability, accessibility, affordability and acceptability for the safe abortion facilities. When abortion is illegal, risk reduction strategies are needed to decrease maternal morbidity and mortality. We can reduce abortion related morbidity and mortality, whether it is legal or illegal if we can ensure the appropriate access to health care, including abortion services, education on sexuality, access to contraceptives, post abortion care, and suitable interventions and liberalization of laws. The paper reviewed the Mexico City Policy and the US foreign aid strategies and highlighted the evidence based analysis for policy reform. The liberalized abortion law can save pregnant women from abortion related complications and death.
Pockett, Rosalie; Peate, Michelle; Hobbs, Kim; Dzidowska, Monika; L Bell, Melanie; Baylock, Brandi; Epstein, Irwin
2016-12-01
To describe the demographics, professional characteristics, self-reported professional development needs and research involvement of oncology social workers in Australia and to describe perceived barriers to provision of quality psychosocial care. A cross-sectional online survey was administered to social workers working in the oncology field who were contacted through three professional organizations; the Australian Association of Social Workers, Oncology Social Work Australia and the Psycho-oncology Co-operative Research Group, the University of Sydney. A snowball recruitment method was adopted to maximize the sample size. Two thirds of respondents had over 10 years professional practice experience but with lesser experience in oncology settings. Twenty-eight percent had post-graduate qualifications. Professional development needs were reported as moderate or high by 68% of respondents. No association between professional needs and work setting was found. Years of experience in oncology practice and living in an urban area increased the likelihood of involvement in research. Barriers to psychosocial care included poor understandings of the social work role, time constraints and an inadequate number of social work positions. In this first Australian study of the social work oncology workforce, the results demonstrated active, well-qualified and experienced social workers providing frontline services to people with cancer and their caregivers in geographically diverse locations across Australia. Inadequate resources and a lack of integrated psychosocial care were identified as barriers to comprehensive cancer care. The need for Aboriginal and Torres Strait Islander social workers was identified as an urgent workforce priority. © 2016 John Wiley & Sons Australia, Ltd.
Advancing the Certified in Public Health Examination: A Job Task Analysis.
Kurz, Richard S; Yager, Christopher; Yager, James D; Foster, Allison; Breidenbach, Daniel H; Irwin, Zachary
In 2014, the National Board of Public Health Examiners performed a job task analysis (JTA) to revise the Certified in Public Health (CPH) examination. The objectives of this study were to describe the development, administration, and results of the JTA survey; to present an analysis of the survey results; and to review the implications of this first-ever public health JTA. An advisory committee of public health professionals developed a list of 200 public health job tasks categorized into 10 work domains. The list of tasks was incorporated into a web-based survey, and a snowball sample of public health professionals provided 4850 usable responses. Respondents rated job tasks as essential (4), very important (3), important (2), not very important (1), and never performed (0). The mean task importance ratings ranged from 2.61 to 3.01 (important to very important). The highest mean ratings were for tasks in the ethics domain (mean rating, 3.01). Respondents ranked 10 of the 200 tasks as the most important, with mean task rankings ranging from 2.98 to 3.39. We found subtle differences between male and female respondents and between master of public health and doctor of public health respondents in their rankings. The JTA established a set of job tasks in 10 public health work domains, and the results provided a foundation for refining the CPH examination. Additional steps are needed to further modify the content outline of the examination. An empirical assessment of public health job tasks, using methods such as principal components analysis, may provide additional insight.
Boyle, Spencer Earl; Jones, Georgina L; Walters, Stephen J
2008-01-01
Background Recent initiatives have been introduced by the UK government into secondary schools to increase pupils' access to physical activity (PA). Despite this, not enough is known about pupils' levels of physical activity or whether the delivery of these initiatives in schools facilitates or creates a barrier for pupils' PA. The aim of this study was to gain an understanding of adolescents PA levels from the perspective of those responsible for delivering physical education (PE) in schools; heads of PE (HOPE) and heads of school (HS). Methods Seventeen semi-structured qualitative interviews were carried out with a snowball sample of HOPE and HS in schools in the Northwest and Southwest of England. Thematic data analysis using NVIVO was used to identify emergent themes. Results 17 core themes were generated, 12 of which confirmed the findings from similar research. However, five themes relating to 'ethos of performance/elitism', 'lower fitness leads to lower ability', 'undervaluing activities within PE dept' or school as a whole', 'role of the school' and 'PE department doing all it can' offer valuable new insight into the factors which may encourage or prevent PA inside or outside the curriculum. Conclusion Despite many positive perceptions of the delivery of PE in schools, it is evident that barriers still exist within that delivery which discourages physical activity. More research is needed to particularly address the complex issues of elitism and the ethos of PA in schools. PMID:18673562
An ethnographic study of barriers to cancer pain management and opioid availability in India.
Lebaron, Virginia; Beck, Susan L; Maurer, Martha; Black, Fraser; Palat, Gayatri
2014-05-01
The world's global cancer burden disproportionally affects lower income countries, where 80% of patients present with late-stage disease and have limited access to palliative care and effective pain-relieving medications, such as morphine. Consequently, millions die each year with unrelieved pain. Objective. The objective of this study was to examine barriers to opioid availability and cancer pain management in India, with an emphasis on the experiences of nurses, who are often the front-line providers of palliative care. Methods. Fifty-nine participants were recruited using a purposive, snowball sampling strategy. Ethnographic data collection included in-depth, semistructured interviews (n = 54), 400+ hours of participant observation, and review of documents over 9 months at a government cancer hospital in South India. Systematic qualitative analysis led to identification of key barriers that are exemplified by representative quotes. Results. Morphine is more available at this study site than in most of India, but access is limited to patients seen by the palliative care service, and significant gaps in supply still occur. Systems to measure and improve pain outcomes are largely absent. Key barriers related to pain management include the role of nursing, opioid misperceptions, bureaucratic hurdles, and sociocultural/infrastructure challenges. Implications. Interventions must streamline process details of morphine procurement, work within the existing sociocultural infrastructure to ensure opioids reach patients most in need, target unexpected audiences for symptom management education, and account for role expectations of health care providers. Conclusion. Macro- and micro-level policy and practice changes are needed to improve opioid availability and cancer pain management in India.
Validation of environmental content in the Young Children's Participation and Environment Measure.
Khetani, Mary A
2015-02-01
To evaluate the concurrent validity of the environment content in the newly developed Young Children's Participation and Environment Measure (YC-PEM). Cross-sectional study. Data were collected online. Convenience and snowball sampling methods were used to survey caregivers of children (N=381; 85 children with developmental disabilities and delays and 296 children without developmental disabilities and delays) aged 0 and 5 years (mean age, 36.49±20.18 mo). Not applicable. The YC-PEM includes an assessment of the effect of environment on children's participation for 3 settings: home, daycare/preschool, and community. Pearson and Spearman correlational analyses were used to examine the concurrent validity of the YC-PEM environmental content according to a criterion measure, the Craig Hospital Inventory of Environmental Factors-Child and Parent Version (CHIEF-CP). The YC-PEM and the CHIEF-CP items were first mapped to the International Classification of Functioning, Disability, and Health-Children and Youth Version to identify items for pairwise comparison. We found small to moderate negative associations for 51 of 66 pairwise comparisons involving CHIEF-CP and YC-PEM environment items (r=-.13 to -.39; P<.01). Significant associations were found for items in all 5 International Classification of Functioning, Disability and Health-Children and Youth Version environmental domains. Results lend further support for the use of the YC-PEM for valid caregiver assessment of the physical, social, attitudinal, and institutional features of environments in terms of their effect on young children's participation within the home, daycare/preschool, and community settings. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
An Ethnographic Study of Barriers to Cancer Pain Management and Opioid Availability in India
Beck, Susan L.; Maurer, Martha; Black, Fraser; Palat, Gayatri
2014-01-01
Background. The world’s global cancer burden disproportionally affects lower income countries, where 80% of patients present with late-stage disease and have limited access to palliative care and effective pain-relieving medications, such as morphine. Consequently, millions die each year with unrelieved pain. Objective. The objective of this study was to examine barriers to opioid availability and cancer pain management in India, with an emphasis on the experiences of nurses, who are often the front-line providers of palliative care. Methods. Fifty-nine participants were recruited using a purposive, snowball sampling strategy. Ethnographic data collection included in-depth, semistructured interviews (n = 54), 400+ hours of participant observation, and review of documents over 9 months at a government cancer hospital in South India. Systematic qualitative analysis led to identification of key barriers that are exemplified by representative quotes. Results. Morphine is more available at this study site than in most of India, but access is limited to patients seen by the palliative care service, and significant gaps in supply still occur. Systems to measure and improve pain outcomes are largely absent. Key barriers related to pain management include the role of nursing, opioid misperceptions, bureaucratic hurdles, and sociocultural/infrastructure challenges. Implications. Interventions must streamline process details of morphine procurement, work within the existing sociocultural infrastructure to ensure opioids reach patients most in need, target unexpected audiences for symptom management education, and account for role expectations of health care providers. Conclusion. Macro- and micro-level policy and practice changes are needed to improve opioid availability and cancer pain management in India. PMID:24755460
The Impact of Minority Stress on Mental Health and Substance Use Among Sexual Minority Women
Lehavot, Keren; Simoni, Jane M.
2014-01-01
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) completed a questionnaire assessing gender expression, minority stressors (i.e., victimization, internalized homophobia, and concealment), social–psychological resources (i.e., social support, spirituality), and health-related outcomes. We used structural equation modeling to test associations among these factors, with gender expression as an antecedent and social–psychological resources as a mediator between minority stress and health. Results The final model demonstrated acceptable fit, χ2(79) = 414.00, p < .05, confirmatory fit index = .93, Tucker–Lewis index = .91, standardized root-mean-square residual = .05, root-mean-square error of approximation = .06, accounting for significant portions of the variance in mental health problems (56%) and substance use (14%), as well as the mediator social–psychological resources (24%). Beyond indirect effects of minority stress on health outcomes, direct links emerged between victimization and substance use and between internalized homophobia and substance use. Conclusions Findings indicate a significant impact of minority stressors and social–psychological resources on mental health and substance use among sexual minority women. The results improve understanding of the distinct role of various minority stressors and their mechanisms on health outcomes. Health care professionals should assess for minority stress and coping resources and refer for evidence-based psychosocial treatments. PMID:21341888