547 research outputs found

    Groundwater characteristics at Seabee Hook, Cape Hallett, Antarctica

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    Seabee Hook is a low lying gravel spit adjacent to Cape Hallett, northern Victoria Land, in the Ross Sea region of Antarctica and hosts an AdĂ©lie penguin (Pygoscelis adeliae) rookery. Dipwells were inserted to monitor changes in depth to, and volume of, groundwater and tracer tests were conducted to estimate aquifer hydraulic conductivity and groundwater velocity. During summer (November–February), meltwater forms a shallow, unconfined, aquifer perched on impermeable ice cemented soil. Groundwater extent and volume depends on the amount of snowfall as meltwater is primarily sourced from melting snow drifts. Groundwater velocity through the permeable gravel and sand was up to 7.8 m day−1, and hydraulic conductivities of 4.7 × 10−4 m s−1 to 3.7 × 10−5 m s−1 were measured. The presence of the penguin rookery, and the proximity of the sea, affects groundwater chemistry with elevated concentrations of salts (1205 mg L−1 sodium, 332 mg L−1 potassium) and nutrients (193 mg L−1 nitrate, 833 mg L−1 ammonia, 10 mg L−1 total phosphorus) compared with groundwater sourced away from the rookery, and with other terrestrial waters in Antarctica

    Sexual health in the South African context

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    Sexual health is a major area of relevance to global public health. The World Health Organization (WHO) has stipulated that every person has the right to sexual health. The United Nations Educational, Scientific and Cultural Organization (UNESCO) has identified sexual rights and sexual health education and training as a global priority. There is also growing interest in human rights and lesbian, gay, bisexual, transgender and intersex (LGBTI) issues internationally. However, there are few centres of excellence for sexual health in low- and middle-income countries, where the vast majority of the world’s population live, and there is a real need to establish such resources.

    Effects of hydrocarbon spills on the temperature and moisture regimes of Cryosols in the Ross Sea region

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    Hydrocarbon spills have occurred on Antarctic soils where fuel oils are utilized, moved or stored. We investigated the effects of hydrocarbon spills on soil temperature and moisture regimes by comparing the properties of existing oil contaminated sites with those of nearby, uncontaminated, control sites at Scott Base, the old Marble Point camp, and Bull Pass in the Wright Valley. Hydrocarbon levels were elevated in fuel-contaminated samples. Climate stations were installed at all three locations in both contaminated and control sites. In summer at Scott Base and Marble Point the mean weekly maximum near surface (2 cm and 5 cm depth) soil temperatures were warmer (P<0.05), sometimes by more than 10°C, at the contaminated site than the control sites. At Bull Pass there were no statistically significant differences in near-surface soil temperatures between contaminated and control soils. At the Scott Base and Marble Point sites soil albedo was lower, and hydrophobicity was higher, in the contaminated soils than the controls. The higher temperatures at the Scott Base and Marble Point hydrocarbon contaminated sites are attributed to the decreased surface albedo due to soil surface darkening by hydrocarbons. There were no noteworthy differences in moisture retention between contaminated and control sites

    Analysis of the Effects of Dietary Pattern on the Oral Microbiome of Elite Endurance Athletes

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    Although the oral microbiota is known to play a crucial role in human health, there are few studies of diet x oral microbiota interactions, and none in elite athletes who may manipulate their intakes of macronutrients to achieve different metabolic adaptations in pursuit of optimal endurance performance. The aim of this study was to investigate the shifts in the oral microbiome of elite male endurance race walkers from Europe, Asia, the Americas and Australia, in response to one of three dietary patterns often used by athletes during a period of intensified training: a High Carbohydrate (HCHO; = 9; with 60% energy intake from carbohydrates; ~8.5 g kg day carbohydrate, ~2.1 g kg day protein, 1.2 g kg day fat) diet, a Periodised Carbohydrate (PCHO; = 10; same macronutrient composition as HCHO, but the intake of carbohydrates is different across the day and throughout the week to support training sessions with high or low carbohydrate availability) diet or a ketogenic Low Carbohydrate High Fat (LCHF; = 10; 0.5 g kg day carbohydrate; 78% energy as fat; 2.1 g kg day protein) diet. Saliva samples were collected both before (Baseline; BL) and after the three-week period (Post treatment; PT) and the oral microbiota profiles for each athlete were produced by 16S rRNA gene amplicon sequencing. Principal coordinates analysis of the oral microbiota profiles based on the weighted UniFrac distance measure did not reveal any specific clustering with respect to diet or athlete ethnic origin, either at baseline (BL) or following the diet-training period. However, discriminant analyses of the oral microbiota profiles by Linear Discriminant Analysis (LDA) Effect Size (LEfSe) and sparse Partial Least Squares Discriminant Analysis (sPLS-DA) did reveal changes in the relative abundance of specific bacterial taxa, and, particularly, when comparing the microbiota profiles following consumption of the carbohydrate-based diets with the LCHF diet. These analyses showed that following consumption of the LCHF diet the relative abundances of and spp. were decreased, and the relative abundance of spp. was increased. Such findings suggest that diet, and, in particular, the LCHF diet can induce changes in the oral microbiota of elite endurance walkers

    Planet Four: Terrains - Discovery of Araneiforms Outside of the South Polar Layered Deposits

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    We present the results of a systematic mapping of seasonally sculpted terrains on the South Polar region of Mars with the Planet Four: Terrains (P4T) online citizen science project. P4T enlists members of the general public to visually identify features in the publicly released Mars Reconnaissance Orbiter CTX images. In particular, P4T volunteers are asked to identify: 1) araneiforms (including features with a central pit and radiating channels known as 'spiders'); 2) erosional depressions, troughs, mesas, ridges, and quasi-circular pits characteristic of the South Polar Residual Cap (SPRC) which we collectively refer to as 'Swiss cheese terrain', and 3) craters. In this work we present the distributions of our high confidence classic spider araneiforms and Swiss cheese terrain identifications. We find no locations within our high confidence spider sample that also have confident Swiss cheese terrain identifications. Previously spiders were reported as being confined to the South Polar Layered Deposits (SPLD). Our work has provided the first identification of spiders at locations outside of the SPLD, confirmed with high resolution HiRISE imaging. We find araneiforms on the Amazonian and Hesperian polar units and the Early Noachian highland units, with 75% of the identified araneiform locations in our high confidence sample residing on the SPLD. With our current coverage, we cannot confirm whether these are the only geologic units conducive to araneiform formation on the Martian South Polar region. Our results are consistent with the current CO2 jet formation scenario with the process exploiting weaknesses in the surface below the seasonal CO2 ice sheet to carve araneiform channels into the regolith over many seasons. These new regions serve as additional probes of the conditions required for channel creation in the CO2 jet process. (Abridged)Comment: accepted to Icarus - Supplemental data files are available at https://www.zooniverse.org/projects/mschwamb/planet-four-terrains/about/results - Icarus print version available at http://www.sciencedirect.com/science/article/pii/S001910351730055

    Best practices for bioinformatic characterization of neoantigens for clinical utility

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    Neoantigens are newly formed peptides created from somatic mutations that are capable of inducing tumor-specific T cell recognition. Recently, researchers and clinicians have leveraged next generation sequencing technologies to identify neoantigens and to create personalized immunotherapies for cancer treatment. To create a personalized cancer vaccine, neoantigens must be computationally predicted from matched tumor-normal sequencing data, and then ranked according to their predicted capability in stimulating a T cell response. This candidate neoantigen prediction process involves multiple steps, including somatic mutation identification, HLA typing, peptide processing, and peptide-MHC binding prediction. The general workflow has been utilized for many preclinical and clinical trials, but there is no current consensus approach and few established best practices. In this article, we review recent discoveries, summarize the available computational tools, and provide analysis considerations for each step, including neoantigen prediction, prioritization, delivery, and validation methods. In addition to reviewing the current state of neoantigen analysis, we provide practical guidance, specific recommendations, and extensive discussion of critical concepts and points of confusion in the practice of neoantigen characterization for clinical use. Finally, we outline necessary areas of development, including the need to improve HLA class II typing accuracy, to expand software support for diverse neoantigen sources, and to incorporate clinical response data to improve neoantigen prediction algorithms. The ultimate goal of neoantigen characterization workflows is to create personalized vaccines that improve patient outcomes in diverse cancer types

    The next generation of fibroblast-based vaccine development

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    Chicken embryo fibroblasts (CEF) and diploid cells have a long history in vaccine production since their isolation in the 1960s at the Wistar Institute (WI-38 cells) as well as the Medical Research Council (MRC-5 cells). The cells quickly became adopted for a number of vaccines: varicella zoster (VZV), MMR, yellow fever, polio, hepatitis A, rotavirus, rabies, Marek\u27s disease, and dengue virus. Most of these vaccine processes were developed with classical media supplemented with Fetal Bovine Serum (FBS). The Hayflick limit of diploid cells restricted their adaptation to a serum-free process. While some of the vaccines such as polio and rabies have been transitioned to Vero cells, several vaccines continue to be manufactured with CEF and human diploid cells. Currently, FBS from Australia and New Zealand are utilized for the highest level of patient safety for human vaccines. However, this supply of serum is challenged by two factors: growth of existing vaccines to improve global access and the development of new gene therapies that require FBS. In order to reduce dependency on serum, we initiated a medium development program. Using metabolite analysis and DOE, we have developed a serum-reduced growth medium and a serum-free virus production medium for MRC-5 and other fibroblast cells. With a serum reduction of 90-100%, the growth medium can support direct recovery from thaw and adaptation-free expansion, resulting in performance that is comparable to classical medium with 10% serum. We confirmed virus production with VZV and vesicular stomatitis virus in MRC-5 cells as well as Marek’s disease virus in CEFs and demonstrate a higher specific productivity. By switching to a low serum process, vaccine manufacturers can reduce production and purification costs, and increase product consistency and safety

    Effects of dietary protein and fiber at breakfast on appetite, ad libitum energy intake at lunch, and neural responses to visual food stimuli in overweight adults

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    Increasing either protein or fiber at mealtimes has relatively modest effects on ingestive behavior. Whether protein and fiber have additive or interactive effects on ingestive behavior is not known. Fifteen overweight adults (5 female, 10 male; BMI: 27.1 ± 0.2 kg/mÂČ; aged 26 ± 1 year) consumed four breakfast meals in a randomized crossover manner (normal protein (12 g) + normal fiber (2 g), normal protein (12 g) + high fiber (8 g), high protein (25 g) + normal fiber (2 g), high protein (25 g) + high fiber (8 g)). The amount of protein and fiber consumed at breakfast did not influence postprandial appetite or ad libitum energy intake at lunch. In the fasting-state, visual food stimuli elicited significant responses in the bilateral insula and amygdala and left orbitofrontal cortex. Contrary to our hypotheses, postprandial right insula responses were lower after consuming normal protein vs. high protein breakfasts. Postprandial responses in other a priori brain regions were not significantly influenced by protein or fiber intake at breakfast. In conclusion, these data do not support increasing dietary protein and fiber at breakfast as effective strategies for modulating neural reward processing and acute ingestive behavior in overweight adults.R01 MH102224 - NIMH NIH HHS; UL1 TR001108 - NCATS NIH HHS; UL1TR001108 - NCATS NIH HH
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