2,587 research outputs found

    The characterization and role of aeolian deposition on water quality, McMurdo Dry Valleys, Antarctica

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    The connection of ecosystems by wind-driven transport of material has become a topic of increasing interest and importance. Less than 1% of dust transported worldwide is exported to the Southern Ocean and Antarctic cryosphere; however, aeolian transport on the Antarctic continent is predominantly locally derived from the abrasion of bedrock. The deposition of the aeolian material is integral to nutrient and solute dispersal in the Antarctic ecosystem. This is particularly true in the ice-free areas of Antarctica, such as the McMurdo Dry Valleys (MDV), where aeolian material deposited in the aquatic system is solubilized during the melt season. The material is predominantly locally-derived from the abrasion of bedrock. In this study, a two-step leaching experiment simulates the melt season and we quantify the flux of solutes and nutrients to the aquatic ecosystem. Soluble salts were removed from the aeolian material first during cold water leaching followed by an increase in carbonate and silicate dissolution during freeze–thaw. Major ion fluxes on glaciers and lakes are at least two orders of magnitude greater than nutrient fluxes. However, the fluxes derived from these experiments are less than the estimated flux from streams to lakes and probably represent minima. Aeolian redistribution of local soils is important because they are the only source of new solutes and nutrients to the aquatic ecosystem of the MDV

    Antarctic streams as a potential source of iron for the Southern Ocean

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    Due to iron’s role in oceanic primary production, there has been great interest in quantifying the importance of Fe in regions where concentrations are very low and macronutrients, nitrate and phosphate, are available. Measurements of filterable (i.e., \u3c0.4 μm) Fe concentrations in streams from Taylor Valley, McMurdo Dry Valleys, Antarctica, suggest that coastal-zone stream Fe input to the Southern Ocean could potentially play an important role in primary production in nearshore regions. Filterable Fe (fFe) data from streams in the McMurdo Dry Valleys were used to represent glacier meltwater that flows through ice-free landscape with the potential of transporting Fe to the Antarctic coastal zone. Estimates of potential fFe flux to the Antarctic Peninsula region using our mean fFe concentration of 10.6 µg L–1 combined with an estimate of ice-free area for the Antarctic Peninsula result in an fFe flux of 1.2 × 107 g yr–1. Although small compared to iceberg and aeolian Fe fluxes, future stream input to the Southern Ocean could increase due to glacier retreat and melting, thus increasing the fFe flux from glacier meltwater streams

    PMM2-CDG caused by uniparental disomy: Case reportand literature review

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    Background Phosphomannomutase 2 deficiency (PMM2-CDG) affects glycosylation pathways such as the N-glycosylation pathway, resulting in loss of function of multiple proteins. This disorder causes multisystem involvement with a high variability among patients. PMM2-CDG is an autosomal recessive disorder, which can be caused by inheriting two pathogenic variants, de novo mutations or uniparental disomy. Case Presentation Our patient presented with multisystem symptoms at an early age including developmental delay, ataxia, and seizures. No diagnosis was obtained till the age of 31 years, when genetic testing was reinitiated. The patient was diagnosed with a complete maternal mixed hetero/isodisomy of chromosome 16, with a homozygous pathogenic PMM2 variant (p.Phe119Leu) causing PMM2-CDG. A literature review revealed eight cases of uniparental disomy as an underlying cause of CDG, four of which are PMM2-CDG. Conclusion Since the incidence of homozygosity for PMM2 variants is rare, we suggest further investigations for every homozygous PMM2-CDG patient where the segregation does not fit. These investigations include testing for UPD or a deletion in one of the two alleles, as this will have an impact on recurrence risk in genetic counselingWe thank the patient described in this case report for all-owing us to share her details, and we thank C. Pérez-Cerdá of the Center of Molecular Biology-Severo Ochoa,Madrid, for her contribution. This work is funded by thegrant titled Frontiers in Congenital Disorders of Glycosylation (1U54NS115198-01) from the National Institute ofNeurological Diseases and Stroke (NINDS) and theNational Center for Advancing Translational Sciences(NCATS), and the Rare Disorders Consortium DiseaseNetwork (E.M. and S.K.

    The role of genotype and production environment in determining the cooking time of dry beans (\u3ci\u3ePhaseolus vulgaris\u3c/i\u3e L.)

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    Dry bean (Phaseolus vulgaris L.) is a nutrient‐dense food rich in proteins and minerals. Although a dietary staple in numerous regions, including Eastern and Southern Africa, greater utilization is limited by its long cooking time as compared with other staple foods. A fivefold genetic variability for cooking time has been identified for P. vulgaris, and to effectively incorporate the cooking time trait into bean breeding programs, knowledge of how genotypes behave across diverse environments is essential. Fourteen bean genotypes selected from market classes important to global consumers (yellow, cranberry, light red kidney, red mottled, and brown) were grown in 10 to 15 environments (combinations of locations, years, and treatments), and their cooking times were measured when either presoaked or unsoaked prior to boiling. The 15 environments included locations in North America, the Caribbean, and Eastern and Southern Africa that are used extensively for dry bean breeding. The cooking times of the 14 presoaked dry bean genotypes ranged from 16 to 156 min, with a mean of 86 min across the 15 production environments. The cooking times of the 14 dry bean genotypes left unsoaked ranged from 77 to 381 min, with a mean cooking time of 113 min. The heritability of the presoaked cooking time was very high (98%) and moderately high for the unsoaked cooking time (~60%). The genotypic cooking time patterns were stable across environments. There was a positive correlation between the presoaked and unsoaked cooking times (r = .64, p \u3c 0.0001), and two of the fastest cooking genotypes when presoaked were also the fastest cooking genotypes when unsoaked (G1, Cebo, yellow bean; and G4, G23086, cranberry bean). Given the sufficient genetic diversity found, limited crossover Genotype × Environment interactions, and high heritability for cooking time, it is feasible to develop fast cooking dry bean varieties without the need for extensive testing across environments

    The role of genotype and production environment in determining the cooking time of dry beans (\u3ci\u3ePhaseolus vulgaris\u3c/i\u3e L.)

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    Dry bean (Phaseolus vulgaris L.) is a nutrient‐dense food rich in proteins and minerals. Although a dietary staple in numerous regions, including Eastern and Southern Africa, greater utilization is limited by its long cooking time as compared with other staple foods. A fivefold genetic variability for cooking time has been identified for P. vulgaris, and to effectively incorporate the cooking time trait into bean breeding programs, knowledge of how genotypes behave across diverse environments is essential. Fourteen bean genotypes selected from market classes important to global consumers (yellow, cranberry, light red kidney, red mottled, and brown) were grown in 10 to 15 environments (combinations of locations, years, and treatments), and their cooking times were measured when either presoaked or unsoaked prior to boiling. The 15 environments included locations in North America, the Caribbean, and Eastern and Southern Africa that are used extensively for dry bean breeding. The cooking times of the 14 presoaked dry bean genotypes ranged from 16 to 156 min, with a mean of 86 min across the 15 production environments. The cooking times of the 14 dry bean genotypes left unsoaked ranged from 77 to 381 min, with a mean cooking time of 113 min. The heritability of the presoaked cooking time was very high (98%) and moderately high for the unsoaked cooking time (~60%). The genotypic cooking time patterns were stable across environments. There was a positive correlation between the presoaked and unsoaked cooking times (r = .64, p \u3c 0.0001), and two of the fastest cooking genotypes when presoaked were also the fastest cooking genotypes when unsoaked (G1, Cebo, yellow bean; and G4, G23086, cranberry bean). Given the sufficient genetic diversity found, limited crossover Genotype × Environment interactions, and high heritability for cooking time, it is feasible to develop fast cooking dry bean varieties without the need for extensive testing across environments

    Confirmatory Factor Analysis of the Pain Care Quality Surveys (Pain CQ © )

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98233/1/hesr12014-sup-0001-Author_matrix.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/98233/2/hesr12014.pd

    Lifetime Risks for Cardiovascular Disease Mortality by Cardiorespiratory Fitness Levels Measured at Ages 45, 55, and 65 Years in Men The Cooper Center Longitudinal Study

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    ObjectivesThe purpose of this study was to determine the association between fitness and lifetime risk for cardiovascular disease (CVD).BackgroundHigher levels of traditional risk factors are associated with marked differences in lifetime risks for CVD. However, data are sparse regarding the association between fitness and the lifetime risk for CVD.MethodsWe followed up 11,049 men who underwent clinical examination at the Cooper Institute in Dallas, Texas, before 1990 until the occurrence of CVD death, non-CVD death, or attainment of age 90 years (281,469 person-years of follow-up, median follow-up 25.3 years, 1,106 CVD deaths). Fitness was measured by the Balke protocol and categorized according to treadmill time into low, moderate, and high fitness, with further stratification by CVD risk factor burden. Lifetime risk for CVD death determined by the National Death Index was estimated for fitness levels measured at ages 45, 55, and 65 years, with non-CVD death as the competing event.ResultsDifferences in fitness levels (low fitness vs. high fitness) were associated with marked differences in the lifetime risks for CVD death at each index age: age 45 years, 13.7% versus 3.4%; age 55 years, 34.2% versus 15.3%; and age 65 years, 35.6% versus 17.1%. These associations were strongest among persons with CVD risk factors.ConclusionsA single measurement of low fitness in mid-life was associated with higher lifetime risk for CVD death, particularly among persons with a high burden of CVD risk factors

    Prenatal Organochlorine Exposure and Measures of Behavior in Infancy Using the Neonatal Behavioral Assessment Scale (NBAS)

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    Background: Previous literature suggests an association between organochlorines and behavioral measures in childhood, including inattention. Objective: This study was designed to assess whether prenatal organochlorine exposure is associated with measures of attention in early infancy. Methods: We investigated an association between cord serum polychlorinated biphenyls (PCBs) and p,p′-dichlorodiphenyl dichloroethene (DDE) levels and measures of attention from the Neonatal Behavioral Assessment Scale (NBAS) in a cohort of 788 infants born 1993–1998 to mothers residing near a PCB-contaminated harbor and Superfund site in New Bedford, Massachusetts. Results: Medians (ranges) for the sum of four prevalent PCB congeners and DDE levels were 0.19 (0.01–4.41) and 0.30 (0–10.29) ng/g serum, respectively. For the 542 subjects with an NBAS exam at 2 weeks, we observed consistent inverse associations between cord serum PCB and DDE levels and NBAS measures of alertness, quality of alert responsiveness, cost of attention, and other potential attention-associated measures including self-quieting and motor maturity. For example, the decrement in quality of alert responsiveness score was −0.51 (95% confidence interval, −0.99 to −0.03) for the highest quartile of exposure to the sum of four prevalent PCB congeners compared with the lowest quartile. We found little evidence for an association with infant orientation, habituation, and regulation of state, assessed as summary cluster measures. Conclusions: Our findings provide evidence for an association between low-level prenatal PCB and DDE exposures and poor attention in early infancy. Further analyses will focus on whether organochlorine-associated decrements in attention and attention-related skills in infancy persist in later childhood
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