274 research outputs found
Identification of \u3ci\u3eFrancisella tularensis\u3c/i\u3e subsp. \u3ci\u3etularensis \u3c/i\u3eA1 and A2 Infections by Real-Time Polymerase Chain Reaction
Francisella tularensis subsp. tularensis (type A) is subdivided into clades A1 and A2. Human tularemia infections caused by A1 and A2 differ with respect to clinical outcome; A1 infections are associated with a higher case fatality rate. In this study, we develop and evaluate TaqMan polymerase chain reaction (PCR) assays for identification of A1 and A2. Both assays were shown to be specific to either A1 or A2, with sensitivities of 10 genomic equivalents. Real-time PCR results for identification of A1 and A2 were in complete agreement with results obtained by pulsed field gel electrophoresis analysis or conventional PCR when specimens from sporadic tularemia cases and a tularemia outbreak involving both A1 and A2 were tested. In addition, outbreak samples not previously typed to the clade level could be classified as A1 or A2. The assays described here provide new diagnostic tools with a level of sensitivity not previously available for identification of A1 and A2 infections
Identification of \u3ci\u3eFrancisella tularensis\u3c/i\u3e subsp. \u3ci\u3etularensis \u3c/i\u3eA1 and A2 Infections by Real-Time Polymerase Chain Reaction
Francisella tularensis subsp. tularensis (type A) is subdivided into clades A1 and A2. Human tularemia infections caused by A1 and A2 differ with respect to clinical outcome; A1 infections are associated with a higher case fatality rate. In this study, we develop and evaluate TaqMan polymerase chain reaction (PCR) assays for identification of A1 and A2. Both assays were shown to be specific to either A1 or A2, with sensitivities of 10 genomic equivalents. Real-time PCR results for identification of A1 and A2 were in complete agreement with results obtained by pulsed field gel electrophoresis analysis or conventional PCR when specimens from sporadic tularemia cases and a tularemia outbreak involving both A1 and A2 were tested. In addition, outbreak samples not previously typed to the clade level could be classified as A1 or A2. The assays described here provide new diagnostic tools with a level of sensitivity not previously available for identification of A1 and A2 infections
General Interviewer Techniques: Developing Evidence-Based Practices for Standardized Interviewing
The practices of standardized interviewing developed at many research sites over many years. The version of standardization that Fowler and Mangione codified in Standardized Survey Interviewing has provided researchers a core resource to use in training and supervising standardized interviewers. In recent decades, however, the accumulation of recordings and transcripts of interviews makes it possible to re-visit the practices of standardization to describe both how respondents actually answer survey questions and how interviewers actually respond.
To update General Interviewer Training (GIT), we brought observations of interaction during interviews together with research about conversational practices from conversation analysis, psychology, and other sources. Using our analysis of the question-answer sequence, we identified the principal actions covered in training as reading a survey question, recognizing a codable answer, acknowledging a codable answer, and follow-up for an uncodable answer. Our analysis of each of these actions is influenced by our observations of the participants’ behavior – interviewers must be trained how to repair the reading of the question, for example -- and by how that behavior is influenced by characteristics of survey questions – follow-up differs for yes-no and selection questions. We developed a set of criteria to use in evaluating the likely impact of the choices we recommend on, for example, interviewer variance and the motivation of the respondent. Although research is not available for all (or even most) criteria, we attempted to be systematic in assessing the likely costs and benefits of our decisions.
We focus on standardized interviewing, which attempts to train interviewers in behaviors that all interviewers can perform in the same way. However, the evidence supplied by studies of interviewer-respondent interaction makes clear that the impact of the question on the respondent’s answer, and the way that respondents answer questions must be taken into account in any style of interviewing
Chapter 3: General Interviewing Techniques: Developing Evidence-Based Practices for Standardized Interviewing Appendix 3
Table A3A.1 Summary of Basic Techniques of Standardized Interviewing (adapted from Fowler and Mangione 1990, pp. 35-53)
Table A3A.2 Basic Question Forms (Response Formats
A Qualitative Evaluation of Double Up Food Bucks Farmers’ Market Incentive Program Access
Objective Explore factors affecting access to and use of Double Up Food Bucks (DUFB), a farmers’ market program that doubles Supplemental Nutrition Assistance Program benefits for use toward the purchase of fruits and vegetables (FV). Design Focus groups. Setting Metro and nonmetro counties in Utah and western Upstate New York. Participants Nine groups composed of 62 low-income adults (3–9/group). Phenomena of Interest Satisfaction with, barriers to, and facilitators of program use; suggestions for improvement. Analysis Transcribed verbatim and coded thematically in NVivo 11 software according to template analysis. Results Program satisfaction was high and driven by FV affordability, perceived support of local farmers, positive market experiences, and high-quality FV. Primary barriers to using DUFB were lack of program information and inconvenient accessibility. Insufficient program communication was a consistent problem that elicited numerous suggestions regarding expansion of program marketing. Emergent topics included issues related to the token-based administration of DUFB and debate regarding stigma experienced during DUFB participation. Conclusions and Implications Results suggest that although DUFB elicits many points of satisfaction among users, program reach may be limited owing to insufficient program marketing. Even among satisfied users, discussion of barriers was extensive, indicating that program reach and impact may be bolstered by efforts to improve program accessibility
Multiple Francisella tularensis Subspecies and Clades, Tularemia Outbreak, Utah
In July 2007, a deer fly–associated outbreak of tularemia occurred in Utah. Human infections were caused by 2 clades (A1 and A2) of Francisella tularensis subsp. tularensis. Lagomorph carcasses from the area yielded evidence of infection with A1 and A2, as well as F. tularensis subsp. holarctica. These findings indicate that multiple subspecies and clades can cause disease in a localized outbreak of tularemia
De novo designed peptide and protein hairpins self‐assemble into sheets and nanoparticles
AFM, TEM, fluorescence microscopy image files and spectral data published in DOI:10.1002/smll.202100472. Preprint of this is available at bioRxiv DOI:10.1101/2020.08.14.25146
Characteristics of HIV-1 Serodiscordant Couples Enrolled in a Clinical Trial of Antiretroviral Pre-Exposure Prophylaxis for HIV-1 Prevention
Stable heterosexual HIV-1 serodiscordant couples in Africa have high HIV-1 transmission rates and are a critical population for evaluation of new HIV-1 prevention strategies. The Partners PrEP Study is a randomized, double-blind, placebo-controlled trial of tenofovir and emtricitabine-tenofovir pre-exposure prophylaxis to decrease HIV-1 acquisition within heterosexual HIV-1 serodiscordant couples. We describe the trial design and characteristics of the study cohort.HIV-1 serodiscordant couples, in which the HIV-1 infected partner did not meet national guidelines for initiation of antiretroviral therapy, were enrolled at 9 research sites in Kenya and Uganda. The HIV-1 susceptible partner was randomized to daily oral tenofovir, emtricitabine-tenofovir, or matching placebo with monthly follow-up for 24-36 months.From July 2008 to November 2010, 7920 HIV-1 serodiscordant couples were screened and 4758 enrolled. For 62% (2966/4758) of enrolled couples, the HIV-1 susceptible partner was male. Median age was 33 years for HIV-1 susceptible and HIV-1 infected partners [IQR (28-40) and (26-39) respectively]. Most couples (98%) were married, with a median duration of partnership of 7.0 years (IQR 3.0-14.0) and recent knowledge of their serodiscordant status [median 0.4 years (IQR 0.1-2.0)]. During the month prior to enrollment, couples reported a median of 4 sex acts (IQR 2-8); 27% reported unprotected sex and 14% of male and 1% of female HIV-1 susceptible partners reported sex with outside partners. Among HIV-1 infected partners, the median plasma HIV-1 level was 3.94 log(10) copies/mL (IQR 3.31-4.53) and median CD4 count was 496 cells/µL (IQR 375-662); the majority (64%) had WHO stage 1 HIV-1 disease.Couples at high risk of HIV-1 transmission were rapidly recruited into the Partners PrEP Study, the largest efficacy trial of oral PrEP. (ClinicalTrials.gov NCT00557245)
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