Evaluation of Xpert® MTB/RIF and ustar easyNAT™ TB IAD for diagnosis of tuberculous lymphadenitis of children in Tanzania : a prospective descriptive study

Fine needle aspiration biopsy has become a standard approach for diagnosis of peripheral tuberculous lymphadenitis. The aim of this study was to compare the performance of Xpert MTB/RIF and Ustar EasyNAT TB IAD nucleic acid amplification assays, against acid-fast bacilli microscopy, cytology and mycobacterial culture for the diagnosis of TB lymphadenitis in children from a TB-endemic setting in Tanzania.; Children of 8 weeks to 16 years of age, suspected of having TB lymphadenitis, were recruited at a district hospital in Tanzania. Fine needle aspirates of lymph nodes were analysed using acid-fast bacilli microscopy, liquid TB culture, cytology, Xpert MTB/RIF and EasyNAT. Latent class analysis and comparison against a composite reference standard comprising "culture and/or cytology" was done, to assess the performance of Xpert MTB/RIF and EasyNAT for the diagnosis of TB lymphadenitis.; Seventy-nine children were recruited; 4 were excluded from analysis. Against a composite reference standard of culture and/or cytology, Xpert MTB/RIF and EasyNAT had a sensitivity and specificity of 58 % and 93 %; and 19 % and 100 % respectively. Relative to latent class definitions, cytology had a sensitivity of 100 % and specificity of 94.7 %.; Combining clinical assessment, cytology and Xpert MTB/RIF may allow for a rapid and accurate diagnosis of childhood TB lymphadenitis. Larger diagnostic evaluation studies are recommended to validate these findings and on Xpert MTB/RIF to assess its use as a solitary initial test for TB lymphadenitis in children

Software defect prediction: do different classifiers find the same defects?

Open Access: This article is distributed under the terms of the Creative Commons Attribution 4.0 International License CC BY 4.0 (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.During the last 10 years, hundreds of different defect prediction models have been published. The performance of the classifiers used in these models is reported to be similar with models rarely performing above the predictive performance ceiling of about 80% recall. We investigate the individual defects that four classifiers predict and analyse the level of prediction uncertainty produced by these classifiers. We perform a sensitivity analysis to compare the performance of Random Forest, Naïve Bayes, RPart and SVM classifiers when predicting defects in NASA, open source and commercial datasets. The defect predictions that each classifier makes is captured in a confusion matrix and the prediction uncertainty of each classifier is compared. Despite similar predictive performance values for these four classifiers, each detects different sets of defects. Some classifiers are more consistent in predicting defects than others. Our results confirm that a unique subset of defects can be detected by specific classifiers. However, while some classifiers are consistent in the predictions they make, other classifiers vary in their predictions. Given our results, we conclude that classifier ensembles with decision-making strategies not based on majority voting are likely to perform best in defect prediction.Peer reviewedFinal Published versio

Judgments of Self-Identified Gay and Heterosexual Male Speakers: Which Phonemes are Most Salient in Determining Sexual Orientation?

While numerous studies have demonstrated that a male speaker’s sexual orientation can be identified from relatively long passages of speech, few studies have evaluated whether listeners can determine sexual orientation when presented with word-length stimuli. If listeners are able to distinguish between self-identified gay and heterosexual male speakers of American English, it is unclear whether they form their judgments based on a phoneme, such as a vowel or consonant, or multiple phonemes, such as a vowel and a consonant. In this study, we first found that listeners can distinguish between self-identified gay and heterosexual speakers of American English upon hearing word-length stimuli. We extended these results in a separate experiment to demonstrate that listeners primarily rely on vowels, and to some extent consonants, when forming their judgments. Listeners were able to differentiate between the two groups of speakers for each of the vowels and three of the seven consonants presented. In a follow-up experiment we found evidence that listeners’ judgments improved if they were presented with multiple phonemes, such as a vowel and /s/. These results provide important information about how different phonemes can provide discriminant information about a male speaker’s sexual orientation

The effects of methane producers and consumers on the diet of Chironomus larvae in an Arctic lake

Up to 40% of methane produced in aquatic systems is oxidized before it is released into the atmosphere. Microbial oxidation of methane is an important sink and potentially an important pathway for the incorporation of detrital carbon into aquatic food webs. In this study, we tested the hypothesis that methane-derived carbon was an important carbon source for Chironomus larvae in a small arctic lake, but that utilization of methane-derived carbon by larvae differed with depth. We found that an order of magnitude more methane was produced at 5m than at 2m. PCR analysis of sediments, found a greater quantity of methanogen DNA at 5m than at 2m, while methanotroph DNA was less common in sediments except for surface sediments. Larval tubes showed a unique composition of methanogen and methanotroph communities when compared to surrounding sediments. A surprisingly larger abundance of methanogens was found in larval hindguts than larval foreguts of Chironomus from deeper sediments. The presence of methanogens and methanotrophs within the larval guts in addition to their depleted d13C signature is consistent with our hypothesis that methane-derived carbon is an important basal food resource in this small lake. Furthermore, the combination of biogeochemical and microbial approaches provides insight into functional differences among habitats for a ubiquitous benthic consumer

Perceptual Characteristics of Gay-Sounding and Heterosexual-Sounding Speech

Numerous research studies have clearly demonstrated that listeners are able to distinguish between self-identified gay and heterosexual male talkers of American English (Gaudio, 1994; Linville, 1998; Munson, McDonald, DeBoe and White, 2006). The results of these studies are less clear as to which acoustic cues listeners rely on when forming their sexual orientation judgments and whether listeners from different geographic regions rely on the same repertoire of acoustic cues. The present series of experiments examined these two issues

Preventing Youth Violence and Delinquency through a Universal School-Based Prevention Approach

Violence is an important public health problem among adolescents in the United States. Substance use and violence tend to co-occur among adolescents and appear to have similar etiologies. The present study examined the extent to which a comprehensive prevention approach targeting an array of individual-level risk and protective factors and previously found effective in preventing tobacco, alcohol, and illicit drug use is capable of decreasing violence and delinquency. Schools (N=41) were randomly assigned to intervention and control conditions. Participants in the 20 intervention schools received the Life Skills Training prevention program including material focusing on violence and the media, anger management, and conflict resolution skills. Survey data were collected from 4,858 sixth grade students prior to the intervention and three months later after the intervention. Findings showed significant reductions in violence and delinquency for intervention participants relative to controls. Stronger prevention effects were found for students who received at least half of the preventive intervention. These effects include less verbal and physical aggression, fighting, and delinquency. The results of this study indicate that a school-based prevention approach previously found to prevent tobacco, alcohol, and illicit drug use can also prevent violence and delinquency

A Longitudinal Examination of Family, Friend, and Media Influences on Competent Versus Problem Behaviors Among Urban Minority Youth

This article examines family, friend, and media influences on competent and problem behaviors in a sample of 1,174 urban minority youth followed over 6th, 7th, and 8th grades. Students completed annual surveys at their schools. Each of the contextual factors investigated was significantly associated with concurrent aggression and delinquency as well as changes in these outcomes over time. In contrast, parental monitoring was most often significantly associated with indicators of competence both concurrently and over time (e.g., from 7th to 8th grade). In addition, engagement with violent media contributed to decreases in academic achievement. Overall, findings indicate that family factors, specifically parental monitoring, as a target of intervention, would not only offset risk trajectories but enhance positive development

Alcohol and Cigarette Free: Examining Social Influences on Substance Use Abstinence among Black Non-Latina and Latina Urban Adolescent Girls

Increases in substance use prevalence among girls, as well as a lack of research conducted with urban girls of color, highlight the importance of understanding both predictors and outcomes of substance use abstinence (SUA) within this population. This study addresses gaps in SUA research through a longitudinal investigation conducted with urban black non-Latina and Latina girls (N = 597) as they transitioned through junior high school. Multivariate logistic regressions found social influences (i.e., friend/family use, drug access) to be significantly associated with girls’ SUA, although differential associations were found by race/ethnicity. SUA was also associated with positive adjustment and wellness by ninth grade. Implications for gender-specific prevention programming are discussed

Attributions : relations to attachment and caregiving representations

"The purpose of this study was to examine associations among maternal attributions for infant behavior, maternal attachment, and representations of the self as caregiver, as well as to examine the stability of maternal attributions from the prenatal to the postpartum period. Eighty-one primiparous mothers completed measures of attachment and attributions for imagined infant behavior in their third trimester of pregnancy and completed measures of attributions for actual infant behavior and caregiving representations at 6 months postpartum. Correlational analyses and multiple regressions were performed. Consistent with predictions, attributions were moderately stable from the prenatal to the postpartum period. Contrary to predictions, mothers with a dismissing attachment classification predominantly accounted for the change in maternal attributions over time. Also consistent with predictions, the attachment-based positive view of the self was associated with maternal investment in the parenting role. However, contrary to predictions, the attachment-based positive view of the self, rather than the positive view of the other, was also associated with prenatal maternal attributions. There were no associations with overall representations of the self as a caregiver or with postpartum maternal attributions. The current study highlights the relationship between attributions and attachment styles and demonstrates the need for further research in this area."--Abstract from author supplied metadata

Through their eyes : a look at achievement and success of selected African American male students

"The presence and implications of societal, institutional, and personal influences on African American male achievement in school was examined in this study. Through in-depth qualitative research strategies, the researcher sought to ascertain the perceptions of 5 African American male students, who are struggling academically and behaviorally in school, regarding the influences they believe are impacting their school experiences. The data confirmed that no single factor is solely responsible for these students' struggles in school. However, there are factors stemming from the societal, institutional, and personal influences that collectively impact their school success. At the institutional and personal levels of influence, factors consist of the lack of engaging instruction, the absence of significant connections to school adults, a limited role of parental support with education, and the negative influence of peers to misbehave in school. Although only one student acknowledges the influence of societal factors related to his surroundings and the cost of success for African American students as a contributor to his lack of success in school, the societal influence lurked beneath the surface of all of the participants' experiences and beliefs."--Abstract from author supplied metadata