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Evaluating cognitive ability, knowledge tests and situational judgement tests for postgraduate selection
Objectives: This study aimed to evaluate the validity and utility of and candidate reactions towards cognitive ability tests, and current selection methods, including a clinical problem-solving test (CPST) and a situational judgement test (SJT), for postgraduate selection.
Methods: This was an exploratory, longitudinal study to evaluate the validities of two cognitive ability tests (measuring general intelligence) compared with current selection tests, including a CPST and an SJT, in predicting performance at a subsequent selection centre (SC). Candidate reactions were evaluated immediately after test administration to examine face validity. Data were collected from candidates applying for entry into training in UK general practice (GP) during the 2009 recruitment process. Participants were junior doctors (n = 260). The mean age of participants was 30.9 years and 53.1% were female. Outcome measures were participants’ scores on three job simulation exercises at the SC.
Results: Findings indicate that all tests measure overlapping constructs. Both the CPST and SJT independently predicted more variance than the cognitive ability test measuring non-verbal mental ability. The other cognitive ability test (measuring verbal, numerical and diagrammatic reasoning) had a predictive value similar to that of the CPST and added significant incremental validity in predicting performance on job simulations in an SC. The best single predictor of performance at the SC was the SJT. Candidate reactions were more positive towards the CPST and SJT than the cognitive ability tests.
Conclusions: In terms of operational validity and candidate acceptance, the combination of the current CPST and SJT proved to be the most effective administration of tests in predicting selection outcomes. In terms of construct validity, the SJT measures procedural knowledge in addition to aspects of declarative knowledge and fluid abilities and is the best single predictor of performance in the SC. Further research should consider the validity of the tests in this study in predicting subsequent performance in training
Genomes of marine cyanopodoviruses reveal multiple origins of diversity
The marine cyanobacteria Prochlorococcus and Synechococcus are highly abundant in the global oceans, as are the cyanophage with which they co-evolve. While genomic analyses have been relatively extensive for cyanomyoviruses, only three cyanopodoviruses isolated on marine cyanobacteria have been sequenced. Here we present nine new cyanopodovirus genomes, and analyse them in the context of the broader group. The genomes range from 42.2 to 47.7 kb, with G+C contents consistent with those of their hosts. They share 12 core genes, and the pan-genome is not close to being fully sampled. The genomes contain three variable island regions, with the most hypervariable genes concentrated at one end of the genome. Concatenated core-gene phylogeny clusters all but one of the phage into three distinct groups (MPP-A and two discrete clades within MPP-B). The outlier, P-RSP2, has the smallest genome and lacks RNA polymerase, a hallmark of the Autographivirinae subfamily. The phage in group MPP-B contain photosynthesis and carbon metabolism associated genes, while group MPP-A and the outlier P-RSP2 do not, suggesting different constraints on their lytic cycles. Four of the phage encode integrases and three have a host integration signature. Metagenomic analyses reveal that cyanopodoviruses may be more abundant in the oceans than previously thought.National Science Foundation (U.S.). Center for Microbial Oceanography: Research and Education (Grant OCE-042560)National Science Foundation (U.S.). Center for Microbial Oceanography: Research and Education (Grant EF 0424599
Gamma hydroxybutyrate (GHB), gamma butyrolactone (GBL) and 1,4 butanediol (1,4-BD; BDO) : a literature review with a focus on UK fatalities related to non-medical use
Misuse of gamma hydroxybutrate (GHB) and gamma butyrolactone (GBL) has increased greatly since the early 1990s, being implicated in a rising number of deaths. This paper reviews knowledge on GHB and derivatives, and explores the largest series of deaths associated with their non-medical use. Descriptive analyses of cases associated with GHB/GBL and 1,4 butanediol (1,4-BD) use extracted from the UK’s National Programme on Substance Abuse Deaths database. From 1995 to September 2013, 159 GHB/GBL-associated fatalities were reported. Typical victims: White (92%), young (mean age 32 years); male (82%); with a drug misuse history (70%). Most deaths (79%) were accidental or related to drug use, the remainder (potential) suicides. GHB/GBL alone was implicated in 37%; alcohol 14%; other drugs 28%; other drugs and alcohol 15%. Its endogenous nature and rapid elimination limit toxicological detection. Post-mortem blood levels: mean 482 (range 0 - 6500; S.D. 758) mg/L. Results suggest significant caution is needed when ingesting GHB/GBL, particularly with alcohol, benzodiazepines, opiates, stimulants, and ketamine. More awareness is needed about risks associated with consumption.Peer reviewe
Transparent Meta-Analysis of Prospective Memory and Aging
Prospective memory (ProM) refers to our ability to become aware of a previously formed plan at the right time and place. After two decades of research on prospective memory and aging, narrative reviews and summaries have arrived at widely different conclusions. One view is that prospective memory shows large age declines, larger than age declines on retrospective memory (RetM). Another view is that prospective memory is an exception to age declines and remains invariant across the adult lifespan. The present meta-analysis of over twenty years of research settles this controversy. It shows that prospective memory declines with aging and that the magnitude of age decline varies by prospective memory subdomain (vigilance, prospective memory proper, habitual prospective memory) as well as test setting (laboratory, natural). Moreover, this meta-analysis demonstrates that previous claims of no age declines in prospective memory are artifacts of methodological and conceptual issues afflicting prior research including widespread ceiling effects, low statistical power, age confounds, and failure to distinguish between various subdomains of prospective memory (e.g., vigilance and prospective memory proper)
Organizational interventions employing principles of complexity science have improved outcomes for patients with Type II diabetes
<p>Abstract</p> <p>Background</p> <p>Despite the development of several models of care delivery for patients with chronic illness, consistent improvements in outcomes have not been achieved. These inconsistent results may be less related to the content of the models themselves, but to their underlying conceptualization of clinical settings as linear, predictable systems. The science of complex adaptive systems (CAS), suggests that clinical settings are non-linear, and increasingly has been used as a framework for describing and understanding clinical systems. The purpose of this study is to broaden the conceptualization by examining the relationship between interventions that leverage CAS characteristics in intervention design and implementation, and effectiveness of reported outcomes for patients with Type II diabetes.</p> <p>Methods</p> <p>We conducted a systematic review of the literature on organizational interventions to improve care of Type II diabetes. For each study we recorded measured process and clinical outcomes of diabetic patients. Two independent reviewers gave each study a score that reflected whether organizational interventions reflected one or more characteristics of a complex adaptive system. The effectiveness of the intervention was assessed by standardizing the scoring of the results of each study as 0 (no effect), 0.5 (mixed effect), or 1.0 (effective).</p> <p>Results</p> <p>Out of 157 potentially eligible studies, 32 met our eligibility criteria. Most studies were felt to utilize at least one CAS characteristic in their intervention designs, and ninety-one percent were scored as either "mixed effect" or "effective." The number of CAS characteristics present in each intervention was associated with effectiveness (p = 0.002). Two individual CAS characteristics were associated with effectiveness: interconnections between participants and co-evolution.</p> <p>Conclusion</p> <p>The significant association between CAS characteristics and effectiveness of reported outcomes for patients with Type II diabetes suggests that complexity science may provide an effective framework for designing and implementing interventions that lead to improved patient outcomes.</p
The normal breast microenvironment of premenopausal women differentially influences the behavior of breast cancer cells in vitro and in vivo
<p>Abstract</p> <p>Background</p> <p>Breast cancer studies frequently focus on the role of the tumor microenvironment in the promotion of cancer; however, the influence of the normal breast microenvironment on cancer cells remains relatively unknown. To investigate the role of the normal breast microenvironment on breast cancer cell tumorigenicity, we examined whether extracellular matrix molecules (ECM) derived from premenopausal African-American (AA) or Caucasian-American (CAU) breast tissue would affect the tumorigenicity of cancer cells <it>in vitro </it>and <it>in vivo</it>. We chose these two populations because of the well documented predisposition of AA women to develop aggressive, highly metastatic breast cancer compared to CAU women.</p> <p>Methods</p> <p>The effects of primary breast fibroblasts on tumorigenicity were analyzed via real-time PCR arrays and mouse xenograft models. Whole breast ECM was isolated, analyzed via zymography, and its effects on breast cancer cell aggressiveness were tested <it>in vitro </it>via soft agar and invasion assays, and <it>in vivo </it>via xenograft models. Breast ECM and hormone metabolites were analyzed via mass spectrometry.</p> <p>Results</p> <p>Mouse mammary glands humanized with premenopausal CAU fibroblasts and injected with primary breast cancer cells developed significantly larger tumors compared to AA humanized glands. Examination of 164 ECM molecules and cytokines from CAU-derived fibroblasts demonstrated a differentially regulated set of ECM proteins and increased cytokine expression. Whole breast ECM was isolated; invasion and soft agar assays demonstrated that estrogen receptor (ER)<sup>-</sup>, progesterone receptor (PR)/PR<sup>- </sup>cells were significantly more aggressive when in contact with AA ECM, as were ER<sup>+</sup>/PR<sup>+ </sup>cells with CAU ECM. Using zymography, protease activity was comparatively upregulated in CAU ECM. In xenograft models, CAU ECM significantly increased the tumorigenicity of ER<sup>+</sup>/PR<sup>+ </sup>cells and enhanced metastases. Mass spectrometry analysis of ECM proteins showed that only 1,759 of approximately 8,000 identified were in common. In the AA dataset, proteins associated with breast cancer were primarily related to tumorigenesis/neoplasia, while CAU unique proteins were involved with growth/metastasis. Using a novel mass spectrometry method, 17 biologically active hormones were measured; estradiol, estriol and 2-methoxyestrone were significantly higher in CAU breast tissue.</p> <p>Conclusions</p> <p>This study details normal premenopausal breast tissue composition, delineates potential mechanisms for breast cancer development, and provides data for further investigation into the role of the microenvironment in cancer disparities.</p
Análise histológica e histoquímica de cistos intra-epiteliais de tubas uterinas de novilhas mestiças
Margarita de Sossa, Sixteenth-Century Puebla de los Ángeles, New Spain (Mexico)
Margarita de Sossa’s freedom journey was defiant and entrepreneurial. In her early twenties, still enslaved in Portugal, she took possession of her body; after refusing to endure her owner’s sexual demands, he sold her, and she was transported to Mexico. There, she purchased her freedom with money earned as a healer and then conducted an enviable business as an innkeeper. Sossa’s biography provides striking insights into how she conceptualized freedom in terms that included – but was not limited to – legal manumission. Her transatlantic biography offers a rare insight into the life of a free black woman (and former slave) in late sixteenth-century Puebla, who sought to establish various degrees of freedom for herself. Whether she was refusing to acquiesce to an abusive owner, embracing entrepreneurship, marrying, purchasing her own slave property, or later using the courts to petition for divorce. Sossa continued to advocate on her own behalf. Her biography shows that obtaining legal manumission was not always equivalent to independence and autonomy, particularly if married to an abusive husband, or if financial successes inspired the envy of neighbors
Production of vegetable oil blends and structured lipids and their effect on wound healing
Two oil blends (sunflower/canola oils 85/15 (BL1) and canola/linseed oils 70/30 (BL2)), were prepared and enzymatically interesterified to be applied to surgically-induced wounds in rats. Following surgery, the animals were submitted to the Treatment with Physiological Saline (TPS) (control group), Blends (TBL), and Structured Lipids (TSL). The control group (TPS) received physiological saline solution for 15 days. In TBL, BL1 was administered during the inflammation phase (days 0-3) and BL2 in the tissue formation and remodeling phase (days 4-15). In TSL, Structured Lipid 1 (SL1) and Structured Lipid 2 (SL2) were used instead of BL1 and BL2, respectively. The aim of this study was to compare wound closure evolution among rats treated with the blends or structured lipids versus control rats treated with physiological saline. The wound healing process was evaluated by measuring the wound areas along the treatments and the concentrations of cytokines. An increase in the areas of wounds treated with the blends and structured lipids in the inflammatory phase was observed, followed by a steeper closure curve compared to wounds treated with physiological saline. The changes observed during the inflammatory phase suggest a potential therapeutic application in cutaneous wound healing which should be further investigated.</p
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