Reproducible variability: assessing investigator discordance across 9 research teams attempting to reproduce the same observational study.

OBJECTIVE: Observational studies can impact patient care but must be robust and reproducible. Nonreproducibility is primarily caused by unclear reporting of design choices and analytic procedures. This study aimed to: (1) assess how the study logic described in an observational study could be interpreted by independent researchers and (2) quantify the impact of interpretations' variability on patient characteristics. MATERIALS AND METHODS: Nine teams of highly qualified researchers reproduced a cohort from a study by Albogami et al. The teams were provided the clinical codes and access to the tools to create cohort definitions such that the only variable part was their logic choices. We executed teams' cohort definitions against the database and compared the number of subjects, patient overlap, and patient characteristics. RESULTS: On average, the teams' interpretations fully aligned with the master implementation in 4 out of 10 inclusion criteria with at least 4 deviations per team. Cohorts' size varied from one-third of the master cohort size to 10 times the cohort size (2159-63 619 subjects compared to 6196 subjects). Median agreement was 9.4% (interquartile range 15.3-16.2%). The teams' cohorts significantly differed from the master implementation by at least 2 baseline characteristics, and most of the teams differed by at least 5. CONCLUSIONS: Independent research teams attempting to reproduce the study based on its free-text description alone produce different implementations that vary in the population size and composition. Sharing analytical code supported by a common data model and open-source tools allows reproducing a study unambiguously thereby preserving initial design choices.

Parasite Population Genetic Contributions to the Schistosomiasis Consortium for Operational Research and Evaluation within Sub-Saharan Africa.

Analyses of the population genetic structure of schistosomes under the "Schistosomiasis Consortium for Operational Research and Evaluation" (SCORE) contrasting treatment pressure scenarios in Tanzania, Niger, and Zanzibar were performed to provide supplementary critical information with which to evaluate the impact of these large-scale control activities and guide how activities could be adjusted. We predicted that population genetic analyses would reveal information on a range of important parameters including, but not exclusive to, recruitment and transmission of genotypes, occurrence of hybridization events, differences in reproductive mode, and degrees of inbreeding, and hence, the evolutionary potential, and responses of parasite populations under contrasting treatment pressures. Key findings revealed that naturally high levels of gene flow and mixing of the parasite populations between neighboring sites were likely to dilute any effects imposed by the SCORE treatment arms. Furthermore, significant inherent differences in parasite fecundity were observed, independent of current treatment arm, but potentially of major impact in terms of maintaining high levels of ongoing transmission in persistent "biological hotspot" sites. Within Niger, naturally occurring Schistosoma haematobium/Schistosoma bovis viable hybrids were found to be abundant, often occurring in significantly higher proportions than that of single-species S. haematobium infections. By examining parasite population genetic structures across hosts, treatment regimens, and the spatial landscape, our results to date illustrate key transmission processes over and above that which could be achieved through standard parasitological monitoring of prevalence and intensity alone, as well as adding to our understanding of Schistosoma spp. life history strategies in general.

Characterisation of cement pastes by inverse gas chromatography.

Two cement pastes, commonly used in concrete formulations, were characterised by IGC at 35-80 degrees C before and after coating with an epoxy resin and a hardener. The cements are mixtures of hydrates in various proportions, such as calcium silicate hydrate (CaO-SiO2-H2O) and calcium hydroxide Ca(OH)2. Apolar and polar probes were used to determine the dispersive and acid-base characteristics of the cement pastes. These materials have high surface energy as judged from the dispersive contribution to the surface free energy (gamma(s)d) values lying in the 50-70 mJ/m2 range at 60-80 degrees C. Examination of the specific interactions permitted to show that the cement pastes are strongly amphoteric species with a substantial predominant Lewis basicity that is in line with the basic pH of their aqueous suspensions. Following coating with an epoxy resin (DGEBA) and a hardener (triethylene tetramine), the surface energy of the cements decreases substantially with the mass loading of the organic material. The surface thermodynamic properties were also correlated with the surface chemical composition as determined by X-ray photoelectron spectroscopy.

Padräo lesional da medula óssea na imunodeficiência adquirida (AIDS) / Lesional pattern of the bone marrow in acquired immunodeficiency syndrome

O estudo da medula óssea em 20 casos de necrópsia de pacientes portadores da Síndrome da Imunodeficiência Adquirida sugere que as alteraçöes medulares säo freqüentes e de valor diagnóstico no reconhecimento da Síndrome. É admitida a existência de um padräo lesional diagnóstico onde predominam os seguintes elementos: hipercelularidade, ausência ou reduçäo da granulopoiese, plasmocitose, histiocitose e displasia megacariocítica

Indicadores quali-quantitativos da assistência de enfermagem nas UTIs de adulto de Curitiba / Quali-quantitative indicator of the nursing assistance in the adults intensive care units in Curitiba

O presente estudo é uma pesquisa exploratório-descritiva, cujo principal objetivo foi diagnosticar os indicadores quali-quantitativos da assistência de enfermagem prestada nas UTIs de Adulto de Curitiba, com o fito de subsidiar futuros estudos sobre a temática. Foi elaborado e aplicado um questionário com questöes abertas e fechadas destinado aos enfermeiros responsáveis pela administraçäo de quatorze (14) UTIs de Adulto de Curitiba que possuem este profissional no seu quadro de pessoal. Os resultados obtidos, revelam que existem dezoito (18) UTIs de Adulto em Curitiba, sendo sete (7) de natureza filantrópica, dez (10) de natureza particular e uma (1) de natureza pública, e que a maioria possui de sete (7) a nove (9) leitos. Verificou-se que a planta física da maior parte das UTIs de Adulto de Curitiba näo segue os requisitos recomendados pela Portaria 400/77 do MS, e que a maioria possui materiais e equipamentos em quantidade suficiente e qualidades adequada. A média de permanência dos pacientes é superior a quarenta e oito (48) horas e os problemas clínicos de maior incidência säo os neurológicos e os cardiovasculares. Um número significativo de enfermeiros respondentes referiram näo terem tido conteúdo de enfermagem em UTI no currículo de graduaçäo, possuem especializaçäo diferente da área em que atuam, däo prevalência as funçöes assistencial e gerencial e näo realizam pesquisas específicas na área. A maioria das UTIs em estudo possui enfermeiros responsáveis pela administraçäo da unidade..