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One of the primary goals of forensic laboratories performing DNA recovery and profiling is obtaining a high-quality DNA extract from crime scene samples. This is largely dependent on the sensitivity and reliability of the DNA extraction chemistry utilised, as well as the liquid handling and contamination minimisation techniques employed. Automation of DNA extraction methods on large liquid handling platforms allows high-throughput laboratories to apply sensitive chemistries to reliably process a large number of samples, while minimising manual processes and cross-contamination.This study describes the first known implementation of the PrepFiler™ Automated Forensic DNA Extraction Kit on a Tecan Fluent® Gx 1080 Automation Workstation. Two Workstations were customised with the addition of novel “Safe Pipetting Modules” to eliminate sample crossover between wells, which is important in a forensic biology setting to reduce inadvertent DNA transfer. A comparison of DNA extraction efficiency between an optimised PrepFiler™ method and the DNA IQ™ System performed on a Perkin Elmer Janus® Integrator platform showed the optimised PrepFiler™ method consistently extracted a higher yield of DNA from a range of blood inputs, as well as blood and buccal swabs. The PrepFiler™ chemistry also more efficiently removed humic acid and haematin, reducing subsequent PCR inhibition. The subsequent implementation of the optimised PrepFiler™ method onto the Tecan Fluent® Gx workstations showed a further increase in sensitivity, with no evidence of DNA cross-contamination observed. However, the optimised PrepFiler™ method encountered difficulties extracting DNA from fabric substrates, with the PrepFiler Express™ chemistry extracting higher yields on the cartridge-based AutoMate Express™ System.Overall, this study demonstrated the Tecan Fluent® Gx 1080 Automation Workstation is a sensitive, reliable and robust method for DNA extraction using the PrepFiler™ Automated Forensic DNA Extraction Kit, and the addition of the novel Safe Pipetting Module makes this platform an attractive option for forensic biology laboratories where minimising inadvertent DNA transfer is of paramount importance.

The James Webb Space Telescope (JWST) has provided the first opportunity of studying the atmospheres of terrestrial exoplanets and estimating their surface conditions. Earth-sized planets around Sun-like stars are currently inaccessible with JWST, however, and will have to be observed using the next generation of telescopes with direct-imaging capabilities. Detecting active volcanism on an Earth-like planet would be particularly valuable as it would provide insight into its interior and provide context for the commonality of the interior states of Earth and Venus. In this work, we used a climate model to simulate four exoEarths over eight years with ongoing large igneous province eruptions with outputs ranging from 1.8 to 60 Gt of sulfur dioxide. The atmospheric data from the simulations were used to model direct-imaging observations between 0.2 and 2.0 μ m, producing reflectance spectra for every month of each exoEarth simulation. We calculated the amount of observation time required to detect each of the major absorption features in the spectra, and we identified the most prominent effects that volcanism had on the reflectance spectra. These effects include changes in the size of the O _3 , O _2 , and H _2 O absorption features and changes in the slope of the spectrum. Of these changes, we conclude that the most detectable and least ambiguous evidence of volcanism are changes in both O _3 absorption and the slope of the spectrum.

Major foodborne bacterial pathogens, such as Campylobacter jejuni, have devised complex strategies to establish and foster intestinal infections. For more than two decades, researchers have used immortalized cell lines derived from human intestinal tissue to dissect C. jejuni-host cell interactions. Known from these studies is that C. jejuni virulence is multifactorial, requiring a coordinated response to produce virulence factors that facilitate host cell interactions. This study was initiated to identify C. jejuni proteins that contribute to adaptation to the host cell environment and cellular invasion. We demonstrated that C. jejuni responds to INT 407 and Caco-2 cells in a similar fashion at the cellular and molecular levels. Active protein synthesis was found to be required for C. jejuni to maximally invade these host cells. Proteomic and transcriptomic approaches were then used to define the protein and gene expression profiles of C. jejuni co-cultured with cells. By focusing on those genes showing increased expression by C. jejuni when co-cultured with epithelial cells, we discovered that C. jejuni quickly adapts to co-culture with epithelial cells by synthesizing gene products that enable it to acquire specific amino acids for growth, scavenge for inorganic molecules including iron, resist reactive oxygen/nitrogen species, and promote host cell interactions. Based on these findings, we selected a subset of the genes involved in chemotaxis and the regulation of flagellar assembly and generated C. jejuni deletion mutants for phenotypic analysis. Binding and internalization assays revealed significant differences in the interaction of C. jejuni chemotaxis and flagellar regulatory mutants. The identification of genes involved in C. jejuni adaptation to culture with host cells provides new insights into the infection process.

Peri-implantitis is an inflammatory disease that results in the destruction of soft tissue and bone around the implant. Titanium implant corrosion has been attributed to the implant failure and cytotoxic effects to the alveolar bone. We have documented the extent of titanium release into surrounding plaque in patients with and without peri-implantitis. An in vitro model was designed to represent the actual environment of an implant in a patient's mouth. The model uses actual oral microbiota from a volunteer, allows monitoring electrochemical processes generated by biofilms growing on implants and permits control of biocorrosion electrical current. As determined by next generation DNA sequencing, microbial compositions in experiments with the in vitro model were comparable with the compositions found in patients with implants. It was determined that the electrical conductivity of titanium implants was the key factor responsible for the biocorrosion process. The interruption of the biocorrosion current resulted in a 4-5 fold reduction of corrosion. We propose a new design of dental implant that combines titanium in zero oxidation state for osseointegration and strength, interlaid with a nonconductive ceramic. In addition, we propose electrotherapy for manipulation of microbial biofilms and to induce bone healing in peri-implantitis patients.

Buried bedrock valleys are common erosional features in northern mid-latitude environments that form through glaciofluvial or paleoalluvial processes and are typically infilled by Quaternary-aged sediments. The erosional extent and geometry of the valley including a weathered interface, along with sediment infill that can contain complex sequences of unconsolidated aquifer and aquitard sediments, mean these features may act as preferential pathways to deeper bedrock aquifers. Noninvasive geophysical tools can provide rapid, high-resolution subsurface characterization of these features. This study evaluates the application of electrical resistivity and seismic refraction tomography along two transects centred over a buried bedrock valley in Elora, Ontario, Canada. Geophysical measurements were combined with existing continuous core records and an electrofacies model based on downhole geophysical logs to constrain the morphology and infilled lithostratigraphic architecture of the valley. Bedrock competency associated with lithology may act as a control on depth and width of valley incision during erosion, with resistivity measurements of the bedrock revealing a potential association between interpreted mechanical properties and variations in the resolved valley morphology. Seismic velocity corroborated these contrasting valley widths but could not assess bedrock competency variability below the bedrock interface. This study reveals the sequence of events depositing sediments in the valley yielding a revised architectural mapping that improves on previous regional scale lithostratigraphic interpretations. Results will be of use to groundwater practitioners requiring detailed conceptualization of this buried bedrock valley and its role on preferential zones of groundwater flow. Similar approaches can be used for delineation of these common and hydrogeologically significant features. Key words: buried bedrock valley electrical resistivity tomography seismic refraction, lithostratigraphic site model, hydrogeologic heterogeneity, 1. Introduction Buried bedrock valleys play an important role in regional groundwater flow systems (e.g., Russell et al. 2004; Cummings et al. 2012; Sharpe et al. 2013, 2018; Bajc et [...]

The Liard Basin, in northwestern Canada, contains one of Canada's largest natural gas reserves. There are concerns about degradation of Dunvegan Formation groundwater quality, which is the basin's main shallow freshwater aquifer, as a consequence of oil and gas development. Previous lithostratigraphic studies interpreted the Dunvegan as conglomeratic alluvial fans. In this study, newly collected cores and surface resistivity surveys are integrated with legacy hydrocarbon well data and measured sections for improved sedimentary bedrock characterization. Rather than alluvial fans, we interpret the upper Dun-vegan as a coarse-sand to gravel bed fluvial system that was likely tributive to incised valleys associated with linked Alberta Basin base-level falls. Correlation of well logs and measured sections suggest the lower Dunvegan comprises a prograding delta complex with off-lapping clinoforms fed by smaller sand-bed rivers that grade into the upper Dunvegan conglomeratic system, which built southeast towards the Cretaceous Western Interior Seaway. This sequence stratigraphic and facies architectural approach is employed to inform the aquifer-aquitard flow system and aid in understanding the 3D groundwater flow system, once hydrogeologic characterisation confirms position and thickness of important hydrogeologic units. Resistivity surveys suggest upper Dunvegan channel-belt facies may be well-connected and laterally extensive, potentially acting as interconnected aquifer units; whereas lower Dunvegan channel belts may be discontinuous, indicating smaller-scale flow units separated by floodplain and marine shale. This revised geologic understanding provides opportunities for determining impacts or resilience from shallow and deep sources of contamination associated with human activities, including oil and gas development, land-use, and (or) climate change. Key words: Dunvegan Formation, Liard Basin, sequence stratigraphic framework, hydrogeologic conceptual model Le bassin de la Liard, dans le nord-ouest du Canada, renferme l'une des plus grandes réserves de gaz naturel de ce pays. La dégradation de la qualité de l'eau souterraine dans la Formation de Dunvegan, le principal aquifère d'eau douce peu profond du bassin, conséquence de la mise en valeur des ressources gazières et pétrolières, suscite des inquiétudes. Des études lithostratigraphiques passées ont interprété la Formation de Dunvegan comme étant formée de cônes alluviaux conglomératiques. Dans la présente étude, des carottes nouvellement prélevées et des levés de résistivité en surface sont intégrés à des données de puits d'hydrocarbure et des coupes mesurées existantes pour obtenir une meilleure caractérisation du substrat sédimentaire. Plutôt que constituée de cônes alluviaux, nous interprétons la Formation de Dunvegan comme étant un réseau fluvial de lits allant de sable grossier à du gravier qui était probablement tributaire de vallées encaissées associées à des chutes au niveau de base du bassin de l'Alberta reliées. La corrélation de profils de sondage et de coupes mesurées indiquerait que la Formation de Dunvegan inférieure comprend un complexe de delta progradant avec des clinoformes régressifs alimentés par de plus petites rivières au lit sablonneux qui passent dans le système conglomératique de la Formation de Dunvegan supérieure, qui elle s'est développée vers le sud-est et la mer intérieure de l'Ouest crétacée. Cette approche de stratigraphie séquentielle et d'architecture de faciès est utilisée pour mieux comprendre le système d'écoulement d'aquifères et d'aquitards et le réseau d'écoulement tridimensionnel de l'eau souterraine, une fois que l'emplacement et l'épaisseur d'unités hydrogéologiques importantes sont confirmés par la caractérisation hydrogéologique. Les levés de résistivité donnent à penser que le faciès de ceintures de chenaux de la Formation de Dunvegan supérieure pourrait être bien connecté et de grande étendue latérale, agissant possiblement comme des unités aquifères interconnectées, alors que les ceintures de chenaux de la Formation de Dunvegan inférieure pourraient être discontinues, indiquant des unités d'écoulement de plus petite échelle séparées par du schiste marin et de plaine inondable. Cette compréhension géologique révisée offre la possibilité de déterminer les impacts de sources de contamination profondes et peu profondes associées à des activités humaines, dont la mise en valeur de ressources gazières et pétrolières, l'occupation du sol et les changements climatiques, ainsi que la résilience à celles-ci. [Traduit par la Rédaction] Mots-clés : Formation de Dunvegan, bassin de la Liard, cadre de stratigraphie séquentielle, modèle conceptuel hydrogéologique, Introduction The Liard Basin, located in the northwest corner of the Western Canada Sedimentary Basin, spans the borders of British Columbia (BC), Yukon (YT), and Northwest Territories (NWT). The region [...]

Technology-mediated simulation is often used in medical problem-based learning (PBL) approaches to offer authentic contexts and immersive engagement for learning. However, critiques argue that these approaches are lacking in the structure necessary to support productive learning--that they often result in mindless doing without the thinking processes needed that lead to deeper understanding and expertise. This paper presents data from a technology-mediated simulation, called HMS MEDscience, to demonstrate: (1) that it effectively leads to greater expert reasoning--evident through responses in content knowledge and problem-solving ability that more closely aligned with a rubric of expert responses to the same questions; (2) through a series of case studies, the implicit pedagogical moves the teachers make to support students' thinking processes. Significant pre- to posttest gains indicate more expert reasoning. In addition, classroom videos indicate shifts from novice toward more expert medical science reasoning and illustrate the fine-grained supporting moves that teachers use to guide students' thinking toward more expert understanding of the problem space. This study highlights the importance of the thinking processes that students engage in as they participate in technology-mediated PBL and the accompanying teacher attention to student thinking through supporting pedagogical moves.

Mitochondrial DNA (mtDNA) is more prevalent than genomic DNA, making it useful for challenging forensic samples such as degraded bones and hair shafts. A comparison of the ForenSeq whole genome and control region mtDNA kits was undertaken on bones burnt to high temperatures and hair shafts covering a range of hair colours and treatments. Haplogroup predictions were made from the same haplogroup branch per donor for one bone burnt ≥ 700°C and all hair segments. Overall, the whole genome mtDNA kit was both more successful and produced more discriminatory haplogroup predictions than the control region kit. [ABSTRACT FROM AUTHOR]

Forensic Investigative Genetic Genealogy (FIGG) offers an alternative pathway for generating leads to aid in the resolution of forensic casework. The ForenSeq® Kintelligence kit is the first commercial panel designed specifically for FIGG applications. In this study, the Kintelligence Kit was compared to the Infinium Global Screening Array-24 Kit on the basis of kinship prediction accuracy between members from a known family group. While both workflows identified kinship links between the primary donor and their family members, the kinship prediction values were not always accurate. Overall, the study demonstrated the potential of FIGG workflows to generate forensic intelligence, but also highlighted the requirement to report links with an appropriate level of caution due to potential discrepancy between the predicted and actual kinship relationship. [ABSTRACT FROM AUTHOR]

Introduction:Telemedicine is a practical way of offering medical services to remote and underserved areas. During the COVID-19 pandemic, telemedicine has provided convenient access to health care and has overcome barriers such as distance that prevent patients from receiving care. Border populations are impacted by this change in health care delivery. The goal of this study was to investigate how a border patient population perceives their experiences with telemedicine. Methods:We utilized telephone surveys of patients who had a recent telehealth visit at the Texas Tech University Health Science Center (TTUHSC) Family Medicine Center clinic in El Paso, Texas. Survey measures included patients' demographics, a quality assessment of the patients' most recent telehealth visit and their experience, a comparison of the patients' telehealth visit to past in-person visits, and a rating of their telehealth visit. Result:Over 2,000 individuals (n = 2,040), primarily Hispanic females, older than the age of 44 years were identified for potential inclusion in the study. Of these, 928 had a contact attempt, of which 1,378 could not be contacted, 592 were invited, 70 declined leading to a response rate of 67.6% (number invited/completed the survey). Most patients agreed that during their most recent telehealth visit their clinician listened well (98.7%), spent adequate time with them (98.2%), was prompt (94.5%), explained things well (98.0%), and was someone they would recommend to others (97.2%). When comparing telehealth to in-person visits, patients reported the following: less wait time, easier convenience, and similar quality between virtual and in-person visits. Patients rated both their likelihood of using telehealth again and their likelihood of recommending telehealth to others as an 8.68 out of 10, on average. Patients 65 years old or older had 3.17 times greater likelihood of satisfaction with virtual visits when compared with patients younger than 45 years old (confidence interval [95% CI], 1.24–11.11). Patients also had less satisfaction with virtual visits if they had lower educational attainment (odds ratio = 0.10; 95% CI, 0.01–0.81). Conclusions:We found that individuals in a border community had a positive experience with telehealth primary care visits. This approach may improve access to health care. [ABSTRACT FROM AUTHOR]

Buried bedrock valleys infilled with Quaternary-aged sediment have the potential to become productive aquifers owing to prevalent sand and gravel deposits often associated with these topographic lows. In areas where groundwater is drawn from the underlying bedrock aquifer, buried bedrock channels may significantly affect the spatial distribution of recharge and localized contaminant pathways. Therefore, understanding the form, distribution, and the nature of Quaternary infill sediments within these buried bedrock river valleys, and their relationship to hydraulically transmissive bedrock features is an important aspect of groundwater resource management. Here, we evaluate the effectiveness of electrical resistivity and seismic refraction collected over a partially urbanized 150 ha area with variable vegetation, roads, and structures, to map the spatial distribution of sediments and delineation of a channel segment associated with a regional bedrock valley. Electrical resistivity and seismic refraction was performed along 13 (covering ~1.6 km) and seven transects (covering --0.9 km), respectively, to map and characterize the bedrock surface morphology beneath a variable thickness of unconsolidated deposits. Three continuously cored holes and downhole geophysical logs, supplemented with four nearby water well records captured the in-channel as well as adjacent Quaternary stratigraphy ( ~15-40 m). Cores recorded multiple glacial till deposits and ice-marginal processes associated with ice advances and retreats. Hydraulic transmissivity of the bedrock around the valley feature was evaluated using a FLUTe hydraulic transmissivity profiling technique. This study demonstrates the potential of combining several surface geophysical methods with sedimentological analysis of continuous cores and hydraulic data for characterizing tributary bedrock channel morphology and Quaternary infill at a scale relevant to localized studies of municipal production well recharge zones and contaminant transport and fate. Les vallées ensevelies taillées dans le roc remplies de sédiments d'âge quaternaire ont le potentiel de devenir des aquifères productifs en raison des importants dépôts de sable et de gravier souvent associés à ces dépressions topographiques. Dans les régions où l'eau souterraine est tirée de l'aquifère rocheux sous-jacent, les chenaux ensevelis taillés dans le roc pourraient avoir une importante incidence sur la répartition spatiale de la recharge et des voies de propagation des contaminants. La compréhension de la forme, de la répartition et de la nature des sédiments quaternaires qui remplissent ces vallées fluviales ensevelies et leur lien avec des caractéristiques du substrat rocheux transmissif est un aspect important de la gestion des ressources d'eau souterraine. Nous évaluons l'efficacité des méthodes de résistivité électrique et de sismique réfraction utilisées dans une zone partiellement urbanisée de 150 ha présentant une répartition variable de la végétation, des routes et des ouvrages, pour cartographier la répartition spatiale des sédiments et les limites d'un tronçon du chenal associé à une vallée taillée dans le roc d'ampleur régionale. Des levés de résistivité électrique et de sismique réfraction ont été réalisés le long de 13 traverses (couvrant ~11,6 km) et sept traverses (couvrant ~0,9 km), respectivement, pour cartographier et caractériser la morphologie de surface du substrat rocheux sous des dépôts meubles d'épaisseur variable. Trois forages carottés en continu et des diagraphies de géophysique de fond, en plus des rapports de quatre puits d'eau situés à proximité, rendent compte de la stratigraphie quaternaire du chenal et des zones attenantes (~15-40 m). Les carottes contiennent différents dépôts de till glaciaire et témoignent de processus proglaciaires associés avec des avancées et retraits de la glace. La transmissivité du roc autour de la vallée a été évaluée par la méthode FLUTe de détermination des profils de transmissivité. L'étude démontre le potentiel qu'offre la combinaison de plusieurs méthodes géophysique à l'analyse sédimentologique de carottes continues et à des données hydrauliques pour caractériser la morphologie de chenaux tributaires taillés dans le roc et leurs matériaux de remplissage quaternaires à une échelle pertinente pour des études localisées de zones de recharge de puits de production municipaux et du transport et du devenir des contaminants. [Traduit par la Rédaction], Introduction Buried bedrock valleys (BBVs) represent an important component of the hydrogeologic conceptual model of southern Ontario and other previously glaciated terrains such as the Canadian Prairies, northern United States, [...]