The transport and deposition of sand is the most prevalent agent of landscape modification on Mars today, with fluxes comparable to some sand dunes on Earth. Until now, the relationship between sand ...flux and dune field morphology has been poorly constrained. By tracking dune movement over ∼10 km-long dune fields in Herschel Crater and Nili Patera, representative of many dune fields on Mars, we find a downwind flux decrease that correlates with a sequence of changing morphology from barchans to barchanoids and seifs (longitudinal dunes) to isolated dome dunes and ending with sand sheets. We show empirical consistency with atmospheric Internal Boundary Layer (IBL) theory which can describe these broad flux and morphology changes in Martian dune fields. Deviations from IBL flux predictions are from wind streamline compressions up slopes, leading to a speedup effect. By establishing a dune field morphology type example and correlating it with measured and predicted flux changes, we provide an integrated morphology and flux model that can be applied to other areas of Mars and be used to infer paleo-environmental conditions from preserved sandstone.
•Mars dune fields exhibit a downwind evolution in morphology and sediment flux.•Internal boundary layer theory and slope speedup explain observed sediment flux.•These findings have implications for interpreting Martian stratigraphy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The deep nitrogen-covered basin on Pluto, informally named Sputnik Planitia, is located very close to the longitude of Pluto's tidal axis and may be an impact feature, by analogy with other large ...basins in the Solar System. Reorientation of Sputnik Planitia arising from tidal and rotational torques can explain the basin's present-day location, but requires the feature to be a positive gravity anomaly, despite its negative topography. Here we argue that if Sputnik Planitia did indeed form as a result of an impact and if Pluto possesses a subsurface ocean, the required positive gravity anomaly would naturally result because of shell thinning and ocean uplift, followed by later modest nitrogen deposition. Without a subsurface ocean, a positive gravity anomaly requires an implausibly thick nitrogen layer (exceeding 40 kilometres). To prolong the lifetime of such a subsurface ocean to the present day and to maintain ocean uplift, a rigid, conductive water-ice shell is required. Because nitrogen deposition is latitude-dependent, nitrogen loading and reorientation may have exhibited complex feedbacks.
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IJS, KISLJ, NUK, SBMB, UL, UM, UPUK
A detailed overview of the knowledge gaps in our understanding of the heliospheric interaction with the largely unexplored Very Local Interstellar Medium (VLISM) are provided along with predictions ...of with the scientific discoveries that await. The new measurements required to make progress in this expanding frontier of space physics are discussed and include in-situ plasma and pick-up ion measurements throughout the heliosheath, direct sampling of the VLISM properties such as elemental and isotopic composition, densities, flows, and temperatures of neutral gas, dust and plasma, and remote energetic neutral atom (ENA) and Lyman-alpha (LYA) imaging from vantage points that can uniquely discern the heliospheric shape and bring new information on the interaction with interstellar hydrogen. The implementation of a pragmatic Interstellar Probe mission with a nominal design life to reach 375 Astronomical Units (au) with likely operation out to 550 au are reported as a result of a 4-year NASA funded mission study.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Background
Overweight and obesity increase the risk of noncommunicable diseases (NCDs). Personalized nutrition (PN) approaches may provide tailored nutritional advice/service by focusing on ...individual's unique characteristics to prevent against NCDs.
Objective
We aimed to compare the effect of PN intervention with the traditional “one size fits all” intervention on health status in overweight/obese Chinese adults.
Methods
In this 12-week randomized controlled trial, 400 adults with BMI ≥24 kg/m
2
were randomized to control group (CG,
n
= 200) and PN group (PNG,
n
= 200). The CG received conventional health guidance according to the
Dietary Guidelines for Chinese Residents
and
Chinese DRIs Handbook
, whereas the PNG experienced PN intervention that was developed by using decision trees based on the subjects' anthropometric measurements, blood samples (phenotype), buccal cells (genotype), and dietary and physical activity (PA) assessments (baseline and updated).
Results
Compared with the conventional intervention, PN intervention significantly improved clinical outcomes of anthropometric (e.g., body mass index (BMI), body fat percentage, waist circumference) and blood biomarkers (e.g., blood lipids, uric acid, homocysteine). The improvement in clinical outcomes was achieved through behavior change in diet and PA. The subjects in the PNG had higher China dietary guidelines index values and PA levels. Personalized recommendations of “lose weight,” “increase fiber” and “take multivitamin/mineral supplements” were the major contributors to the decrease of BMI and improvement of lipid profile.
Conclusion
We provided the first evidence that PN intervention was more beneficial than conventional nutrition intervention to improve health status in overweight/obese Chinese adults. This study provides a model of framework for developing personalized advice in Chinese population.
Chictr.org.cn
(ChiCTR1900026226).
Large ripples form striking patterns on the slopes of martian sand dunes which can be mapped and tracked using high-resolution optical images. The ripples vary in orientation, wavelength, plan-view ...morphology, and rates of migration. The variations in the ripple patterns are recognized to signal the effects of the regional and local winds and feedbacks between winds and dune topography. We examine the ripple patterns and the motion of these ripples to interpret airflow dynamics around dunes in the dune field at Nili Patera. We find that coincident changes in ripple patterns and migration rates in dune wakes indicate reattachment lengths of 4–7 brink heights. This reattachment length is similar to length scales of flow reattachment for airflow over dunes measured on Earth despite the differences in aeolian environment. Furthermore, ripples on dune flanks are shown to behave according to terrestrial models for ripple development on steep slopes. Compensating for these slope effects allows them to act as indicators of dune-modified and regional wind directions. Changes in ripple patterns and migration rates also signal the response of dunes and airflow during dune collisions. Collectively, we find that differences in ripple patterns connected to changes in migration rate provide information on airflow over and around dunes. This detailed assessment of ripple measurement and ripple migration rates advances the use of ripples on martian dunes and sand sheets to infer dune- and field-scale wind dynamics. These measurements also indicate that the low density atmosphere on Mars does not significantly modify the behavior of wind-topography interactions compared to Earth. Such observations provide targets for computational fluid dynamic and large-eddy simulation models seeking to reveal complex airflows across dune fields both on Earth and on Mars.
This article demonstrates that a simple chemical model system, built by using a modular approach, may be used to predict the spatiotemporal dynamics of initiation of blood clotting in the complex ...network of hemostasis. Microfluidics was used to create in vitro environments that expose both the complex network and the model system to surfaces patterned with patches presenting clotting stimuli. Both systems displayed a threshold response, with clotting initiating only on isolated patches larger than a threshold size. The magnitude of the threshold patch size for both systems was described by the Damköhler number, measuring competition of reaction and diffusion. Reaction produces activators at the patch, and diffusion removes activators from the patch. The chemical model made additional predictions that were validated experimentally with human blood plasma. These experiments show that blood can be exposed to significant amounts of clot-inducing stimuli, such as tissue factor, without initiating clotting. Overall, these results demonstrate that such chemical model systems, implemented with microfluidics, may be used to predict spatiotemporal dynamics of complex biochemical networks.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Feelings of shame have been found to be an important mediating factor in influencing a child's recovery from abuse. This article conceptualizes the development and maintenance of shame in the ...aftermath of experiencing child sexual and/or physical abuse. Research is reviewed that may shed light on the impact of shame and dysfunctional attributions with a view toward understanding how this type of painful emotional suffering can be prevented and/or treated. Trauma-focused interventions that have demonstrated efficacy in helping children overcome feelings of shame are described. Directions for future research that may further our understanding of the development, impact, and treatment of feelings of shame are suggested.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
Abstract This preliminary investigation assessed whether different aspects of personal resiliency improved for youth (7–17 years old) impacted by child sexual abuse (CSA) after completing ...trauma-focused cognitive behavioral therapy (TF-CBT). The Resiliency Scales for Children and Adolescents (RSCA; Prince-Embury, 2007) were administered to 157 youth before and after participating in TF-CBT with their nonoffending caregivers. Hierarchal regression analyses were performed to ascertain whether pretest RSCA resiliency scores moderated decreases in the posttraumatic stress and self-reported depressive symptoms at posttreatment. The RSCA scales did not moderate any of the improvements on the PTSD and depression outcome measures. Paired t -tests between the mean pre- and posttest RSCA Sense of Mastery (MAS), Sense of Relatedness (REL), and Emotional Reactivity (REA) scores demonstrated significant (ps < 0.001) improvements on these measures over time. Using residualized posttest scores for the three RSCA scales to assess improvement, significant correlations were found between changes in resiliency and various residualized outcome scores for posttraumatic stress disorder (PTSD) and depression measures. Decreases in the REA scores and increases in the MAS and REL scores were related to fewer symptoms of hypervigilance and less self-reported depression after completing TF-CBT. Only improvements in the REL scores were associated with fewer symptoms of re-experiencing after treatment. The results were discussed as indicating that significant improvements in personal resiliency had occurred over time with effect sizes less than those found for posttraumatic stress symptoms, but comparable to those found for self-reported depression reductions. Limitations and future research recommendations are discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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