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Se verifica en St. Lawrence Lowlands en SW Quebec un método de evaluación de vulnerabilidad acuífera, el cual relaciona directamente Ia vulnerabilidad con el tiempo advectivo descendiente (DAT) a partir de un modelo geológico 3D. El objetivo fue evaluar Ia vulnerabilidad del acuífero regional, el cual es sobreyacido por unidades Cuaternarias discontinuas y no consolidadas. Parámetros hidrogeológicos como Ia recarga y la porosidad de cada unidad sobreyaciente fueron integrados a una malla estratigráfica gOcad. Esta malla fue generada a partir de un modelo geológico hecho con superficies entrelazadas representando las fronteras de las unidades Cuaternarias y Ia topografía del basamento. Se hicieron cálculos usando 1m enfoque determinístico y valores de DAT fueron obtenidos para el 74% del área en estudio. Los resultados son agrupados en 6 clases DAT, los cuales son interpretados en términos de un índice de vulnerabilidad relativa. La distribución espacial de este índice concuerda con el escenario hidrogeológico y los datos hidrogeoquímicos disponibles. Los resultados indican que 40% del área evaluada cae en clases de moderadamente alta a muy alta vulnerabilidad. Una comparación entre este mapa y no DRASTIC de Ia misma área revelan algunas discrepancias significantes, particularmente en áreas de profundidad somera a! basamento, las cuales son caracterizadas por rápidos DAT a través de Ia delgada zona vadosa. En estas áreas DRASTIC produce vulnerabilidades bajas mientras esta evaluación da valores altos de vulnerabilidad. Esta valoración provee bases legítimas para una planificación regional y !a toma de decisiones. doi: https://doi.org/10.22201/igeof.00167169p.2004.43.4.828

An aquifer vulnerability assessment method which relates vulnerability directly to groundwater Downward Advective Time (DAT) from a 3D geologic model is tested over a 1400 km2 area in the St. Lawrence Lowlands in SW Québec. The goal was to assess the vulnerability of the regional rock aquifer which is overlain by discontinuous and unconsolidated Quaternary units. Hydrogeologic parameters such as groundwater recharge and porosity of each unit overlying the aquifer were integrated to a gOcad 3D stratigraphic grid. This grid was generated from a 3D geologic model made of interlocked surfaces representing the boundaries of Quaternary units and the underlying bedrock topography. Calculations were carried out using a deterministic approach and DAT estimates were obtained for 74% of the model area. Results are tentatively grouped into 6 DAT classes which are interpreted in terms of a relative vulnerability index. The spatial distribution of this index is in good agreement with the hydrogeological settings and available hydrogeochemical data. Results indicate that 40% of the evaluated area falls within the moderately high to very high vulnerability classes. Comparison between this map and a DRASTIC map of the same area reveals some significant discrepancies, particularly in areas of shallow depth to bedrock which are characterized by fast DAT through a thick unsaturated zone. In these areas DRASTIC produces low vulnerability scores while this assessment yields high vulnerability ranking. Overall, this assessment provides a sound basis for regional planning and decision making.

BRAAVE (NCT03631732), a Phase 3b, multicenter, open‐label US study, demonstrated the efficacy of switching to bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) among Black individuals with suppressed HIV through 48 weeks. Here, 72‐week resistance, adherence, and virologic outcomes are presented. Enrollment criteria permitted nonnucleoside reverse transcriptase inhibitor (NNRTI)–resistance (R), protease inhibitor (PI)–R, and certain nucleos(t)ide reverse transcriptase inhibitor (NRTI)–R (M184V/I allowed; ≥3 thymidine analog mutations [TAMs] excluded); but excluded primary integrase strand transfer inhibitor (INSTI)‐R. Pre‐existing resistance was determined using historical genotypes and retrospective baseline proviral DNA genotyping. Adherence, virologic outcomes, and viral blips were assessed. Of 489 participants receiving B/F/TAF with ≥1 post‐switch HIV‐1 RNA measurement: pre‐existing NRTI‐R (15% of participants), M184V/I (11%), ≥1 TAMs (8%), NNRTI‐R (22%), and PI‐R (13%) were observed; pre‐existing INSTI‐R substitutions (2%) were detected post‐randomization; mean viral blip frequency was 0.9% across all timepoints (unassociated with virologic failure); 24% of participants had <95% adherence (98% of whom had HIV‐1 RNA <50 copies/mL at last visit); none had treatment‐emergent study‐drug resistance. Overall, 99% of participants, including all with baseline NRTI‐R/INSTI‐R, had HIV‐1 RNA <50 copies/mL at the last visit, demonstrating that B/F/TAF maintained virologic suppression through 72 weeks regardless of pre‐existing resistance, viral blips, and suboptimal adherence. [ABSTRACT FROM AUTHOR]

Genomic sequencing of clinical samples to identify emerging variants of SARS-CoV-2 has been a key public health tool for curbing the spread of the virus. As a result, an unprecedented number of SARS-CoV-2 genomes were sequenced during the COVID-19 pandemic, which allowed for rapid identification of genetic variants, enabling the timely design and testing of therapies and deployment of new vaccine formulations to combat the new variants. However, despite the technological advances of deep sequencing, the analysis of the raw sequence data generated globally is neither standardized nor consistent, leading to vastly disparate sequences that may impact identification of variants. Here, we show that for both Illumina and Oxford Nanopore sequencing platforms, downstream bioinformatic protocols used by industry, government, and academic groups resulted in different virus sequences from same sample. These bioinformatic workflows produced consensus genomes with differences in single nucleotide polymorphisms, inclusion and exclusion of insertions, and/or deletions, despite using the same raw sequence as input datasets. Here, we compared and characterized such discrepancies and propose a specific suite of parameters and protocols that should be adopted across the field. Consistent results from bioinformatic workflows are fundamental to SARS-CoV-2 and future pathogen surveillance efforts, including pandemic preparation, to allow for a data-driven and timely public health response. [ABSTRACT FROM AUTHOR]

Video tutorials are a common form of library instruction used with distance learners. This paper combines professional experience and literature reviews from multiple disciplines to provide a contextual overview of recommendations and findings for effective and engaging videos. The tools for tutorials appear in five main categories: screencasts, slidecasts, live action video, animation, and interactivity. Not all tools work for every task or skill level, so it is important to have an understanding of the options available to creators. While the category and combination of tools used can vary, some general design principles and considerations apply to any form of online video. The type and length of content, compatibility with different devices, accessibility to all viewers, and quality audio are vital to making video tutorials that distance learners will want to watch.