1,358 research outputs found
Reproductive Output and Seasonality of Limnoperna fortunei
Fil: Boltovskoy, Demetrio. Instituto de EcologĂa. GenĂ©tica y EvoluciĂłn de Buenos Aires (IEGEBA). Universidad de Buenos Aires; ArgentinaFil: Morton, Brian. School of Biological Sciences. University of Hong Kong; ChinaFil: Correa, Nancy. Servicio de HidrografĂa Naval. Ministerio de Defensa. Escuela de Ciencias del Mar. Instituto Universitario Naval; ArgentinaFil: Cataldo, Daniel. Departamento de Ciencias BiolĂłgicas. Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires; ArgentinaFil: Damborenea, MarĂa Cristina. DivisiĂłn ZoologĂa Invertebrados. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Penchaszadeh, Pablo E.. Museo Argentino de Ciencias Naturales Bernardino Rivadavia; ArgentinaFil: Sylvester, Francisco. Instituto para el Estudio de la Biodiversidad de Invertebrados. Facultad de Ciencias Naturales. Universidad Nacional de Salta; Argentin
Effects of Proportions of Dietary Macronutrients on Glucocorticoid Metabolism in Diet-Induced Obesity in Rats
Tissue glucocorticoid levels in the liver and adipose tissue are regulated by regeneration of inactive glucocorticoid by 11ÎČ-hydroxysteroid dehydrogenase type 1 (11ÎČ-HSD1) and inactivation by 5α- and 5ÎČ-reductases. A low carbohydrate diet increases hepatic 11ÎČ-HSD1 and reduces glucocorticoid metabolism during weight loss in obese humans. We hypothesized that similar variations in macronutrient proportions regulate glucocorticoid metabolism in obese rats. Male Lister Hooded rats were fed an obesity-inducing ad libitum âWesternâ diet (37% fat, nâ=â36) for 22 weeks, then randomised to continue this diet (nâ=â12) or to switch to either a low carbohydrate (nâ=â12) or a moderate carbohydrate (nâ=â12) diet for the final 8 weeks. A parallel lean control group were fed an ad libitum control diet (10% fat, nâ=â12) throughout. The low and moderate carbohydrate diets decreased hepatic 11ÎČ-HSD1 mRNA compared with the Western diet (both 0.7±0.0 vs 0.9±0.1 AU; p<0.01), but did not alter 11ÎČ-HSD1 in adipose tissue. 5α-Reductase mRNA was increased on the low carbohydrate compared with the moderate carbohydrate diet. Compared with lean controls, the Western diet decreased 11ÎČ-HSD1 activity (1.6±0.1 vs 2.8±0.1 nmol/mcg protein/hr; p<0.001) and increased 5α-reductase and 5ÎČ-reductase mRNAs (1.9±0.3 vs 1.0±0.2 and 1.6±0.1 vs 1.0±0.1 AU respectively; p<0.01) in the liver, and reduced 11ÎČ-HSD1 mRNA and activity (both p<0.01) in adipose tissue. Although an obesity-inducing high fat diet in rats recapitulates the abnormal glucocorticoid metabolism associated with human obesity in liver (but not in adipose tissue), a low carbohydrate diet does not increase hepatic 11ÎČ-HSD1 in obese rats as occurs in humans
Molecular Hydrogen in the FUSE Translucent Lines of Sight: The Full Sample
We report total abundances and related parameters for the full sample of the
FUSE survey of molecular hydrogen in 38 translucent lines of sight. New results
are presented for the "second half" of the survey involving 15 lines of sight
to supplement data for the first 23 lines of sight already published. We assess
the correlations between molecular hydrogen and various extinction parameters
in the full sample, which covers a broader range of conditions than the initial
sample. In particular, we are now able to confirm that many, but not all, lines
of sight with shallow far-UV extinction curves and large values of the
total-to-selective extinction ratio, = / -- characteristic
of larger than average dust grains -- are associated with particularly low
hydrogen molecular fractions (). In the lines of sight with large
, there is in fact a wide range in molecular fractions, despite the
expectation that the larger grains should lead to less H formation.
However, we see specific evidence that the molecular fractions in this
sub-sample are inversely related to the estimated strength of the UV radiation
field and thus the latter factor is more important in this regime. We have
provided an update to previous values of the gas-to-dust ratio, (H)/, based on direct measurements of (H) and (H I).
Although our value is nearly identical to that found with Copernicus data, it
extends the relationship by a factor of 2 in reddening. Finally, as the new
lines of sight generally show low to moderate molecular fractions, we still
find little evidence for single monolithic "translucent clouds" with 1.Comment: 35 pages, 5 tables, 7 figures, accepted for publication in The
Astrophysical Journal Supplements Serie
Nutrient content and stoichiometry of pelagic Sargassum reflects increasing nitrogen availability in the Atlantic Basin
© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Lapointe, B. E., Brewton, R. A., Herren, L. W., Wang, M., Hu, C., McGillicuddy, D. J., Lindell, S., Hernandez, F. J., & Morton, P. L. Nutrient content and stoichiometry of pelagic Sargassum reflects increasing nitrogen availability in the Atlantic Basin. Nature Communications, 12(1), (2021): 3060, https://doi.org/10.1038/s41467-021-23135-7.The pelagic brown macroalgae Sargassum spp. have grown for centuries in oligotrophic waters of the North Atlantic Ocean supported by natural nutrient sources, such as excretions from associated fishes and invertebrates, upwelling, and N2 fixation. Using a unique historical baseline, we show that since the 1980s the tissue %N of Sargassum spp. has increased by 35%, while %P has decreased by 44%, resulting in a 111% increase in the N:P ratio (13:1 to 28:1) and increased P limitation. The highest %N and ÎŽ15N values occurred in coastal waters influenced by N-rich terrestrial runoff, while lower C:N and C:P ratios occurred in winter and spring during peak river discharges. These findings suggest that increased N availability is supporting blooms of Sargassum and turning a critical nursery habitat into harmful algal blooms with catastrophic impacts on coastal ecosystems, economies, and human health.This work was funded by the US NASA Ocean Biology and Biogeochemistry Program (80NSSC20M0264, NNX16AR74G) and Ecological Forecast Program (NNX17AF57G), NOAA RESTORE Science Program (NA17NOS4510099), National Science Foundation (NSF-OCE 85â15492 and OCE 88â12055), âSave Our Seasâ Specialty License Plate funds, granted through the Harbor Branch Oceanographic Institute Foundation, Ft. Pierce, FL, and a Red Wright Fellowship from the Bermuda Biological Station. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by National Science Foundation Cooperative Agreement No. DMR-1644779 and the State of Florida. D.J.M. gratefully acknowledges the Holger W. Jannasch and Columbus OâDonnell Iselin Shared Chairs for Excellence in Oceanography, as well as support from the Mill Reef Fund
Impaired self awareness after traumatic brain injury: inter-rater reliability and factor structure of the dysexecutive questionnairre (DEX) in patients, significant others and clinicians
Aims: This study sought to address two questions: (1) what is the inter-rater reliability
of the Dysexecutive Questionnaire (DEX) when completed by patients, their significant
others, and clinicians; and (2) does the factor structure of the DEX vary for these three
groups?
Methods: We obtained DEX ratings for 113 patients with an acquired brain injury from
two brain injury services in the UK and two services in Ireland. We gathered data from
two groups of ratersââsignificant othersâ (DEX-SO) such as partners and close family
members and âcliniciansâ (DEX-C), who were psychologists or rehabilitation physicians
working closely with the patient and who were able to provide an opinion about the
patientâs level of everyday executive functioning. Intra-class correlation coefficients and
their 95% confidence intervals were calculated between each of the three groups (self,
significant other, clinician). Principal axis factor (PAF) analyses were also conducted for
each of the three groups.
Results: The factor analysis revealed a consistent one-factor model for each of the
three groups of raters. However, the inter-rater reliability analyses showed a low level of
agreement between the self-ratings and the ratings of the two groups of independent
raters. We also found low agreement between the significant others and the clinicians.
Conclusion: Although there was a consistent finding of a single factor solution for each
of the three groups, the low level of agreement between significant others and clinicians
raises a question about the reliability of the DEX.</p
Impaired self awareness after traumatic brain injury: inter-rater reliability and factor structure of the dysexecutive questionnairre (DEX) in patients, significant others and clinicians
Aims: This study sought to address two questions: (1) what is the inter-rater reliability
of the Dysexecutive Questionnaire (DEX) when completed by patients, their significant
others, and clinicians; and (2) does the factor structure of the DEX vary for these three
groups?
Methods: We obtained DEX ratings for 113 patients with an acquired brain injury from
two brain injury services in the UK and two services in Ireland. We gathered data from
two groups of ratersââsignificant othersâ (DEX-SO) such as partners and close family
members and âcliniciansâ (DEX-C), who were psychologists or rehabilitation physicians
working closely with the patient and who were able to provide an opinion about the
patientâs level of everyday executive functioning. Intra-class correlation coefficients and
their 95% confidence intervals were calculated between each of the three groups (self,
significant other, clinician). Principal axis factor (PAF) analyses were also conducted for
each of the three groups.
Results: The factor analysis revealed a consistent one-factor model for each of the
three groups of raters. However, the inter-rater reliability analyses showed a low level of
agreement between the self-ratings and the ratings of the two groups of independent
raters. We also found low agreement between the significant others and the clinicians.
Conclusion: Although there was a consistent finding of a single factor solution for each
of the three groups, the low level of agreement between significant others and clinicians
raises a question about the reliability of the DEX.</p
A pilot sequential multiple assignment randomized trial (SMART) protocol for developing an adaptive coaching intervention around a mobile application for athletes to improve carbohydrate periodization behavior
Background: It has recently been identified that manipulating carbohydrate availability around exercise activity can enhance training-induced metabolic adaptations. Despite this approach being accepted in the athletic populations, athletes do not systematically follow the guidelines. Digital environments appear to allow nutritionists to deliver this intervention at scale, reducing expensive human coaching time. Yet, digitally delivered dietary behavior change interventions for athletes and the coaching strategy to support them are still novel concepts within sports nutrition. Methods/design: We aim to recruit 900 athletes across the UK. 500 athletes will be recruited to test the feasibility of a novel menu planner mobile application with coaching for 6 weeks. 250 athletes with pre-existing nutritionist support will also be recruited as control. We will then conduct a 4-week pilot sequential multiple assignment randomized trial (SMART) with an additional 150 athletes. In the SMART, athletes will be given the application and additional coaching according to their engagement responses. The primary outcomes are the mobile application and coach uptake, retention, engagement, and success in attaining carbohydrate periodization behavior. Secondary outcomes are changes in goal, weight, carbohydrate periodization self-efficacy, and beliefs about consequences. Due to the high attrition nature of digital interventions, all quantitative analyses will be carried out based on both the intention-to-treat and per-protocol principles. Discussion: This study will be the first to investigate improving carbohydrate periodization using a digital approach and tailored coaching strategies under this context. Foundational evidence from this study will provide insights into the feasibility of the digital approach
Rebuilding relationships on coral reefs: Coral bleaching knowledge-sharing to aid adaptation planning for reef users: Bleaching emergence on reefs demonstrates the need to consider reef scale and accessibility when preparing for, and responding to, coral bleaching
Coral bleaching has impacted reefs worldwide and the predictions of near-annual bleaching from over two decades ago have now been realized. While technology currently provides the means to predict large-scale bleaching, predicting reef-scale and within-reef patterns in real-time for all reef users is limited. In 2020, heat stress across the Great Barrier Reef underpinned the region's third bleaching event in 5 years. Here we review the heterogeneous emergence of bleaching across Heron Island reef habitats and discuss the oceanographic drivers that underpinned variable bleaching emergence. We do so as a case study to highlight how reef end-user groups who engage with coral reefs in different ways require targeted guidance for how, and when, to alter their use of coral reefs in response to bleaching events. Our case study of coral bleaching emergence demonstrates how within-reef scale nowcasting of coral bleaching could aid the development of accessible and equitable bleaching response strategies on coral reefs. Also see the video abstract here: https://youtu.be/N9Tgb8N-vN0
Reproductive Output and Seasonality of <i>Limnoperna fortunei</i>
Young Limnoperna fortunei mature sexually from 5â6 to ~15 mm. The species is generally dioecious, with approximately equal numbers of males and females and very small (3, but, normally, values range around 6000 ind./m3, showing major fluctuations within short periods, as well as changes as a function of time elapsed post colonization, and availability of substrata suitable for adult occupation. Microcystin-producing cyanobacterial blooms can kill L. fortunei larvae.Facultad de Ciencias Naturales y Muse
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