2,158 research outputs found
Microvascular Dysfunction Is Associated With a Higher Incidence of Type 2 Diabetes Mellitus A Systematic Review and Meta-Analysis
Objective-Recent data support the hypothesis that microvascular dysfunction may be a potential mechanism in the development of insulin resistance. We examined the association of microvascular dysfunction with incident type 2 diabetes mellitus (T2DM) and impaired glucose metabolism by reviewing the literature and conducting a meta-analysis of longitudinal studies on this topic. Methods and Results-We searched Medline and Embase for articles published up to October 2011. Prospective cohort studies that focused on microvascular measurements in participants free of T2DM a baseline were included. Pooled relative risks were calculated using random effects models. Thirteen studies met the inclusion criteria for this meta-analysis. These studies focused on T2DM or impaired fasting glucose, not on impaired glucose tolerance. The pooled relative risks for incident T2DM (3846 cases) was 1.25 (95% confidence interval, 1.15; 1.36) per 1 SD greater microvascular dysfunction when all estimates of microvascular dysfunction were combined. In analyses of single estimates of microvascular dysfunction, the pooled relative risks for incident T2DM was 1.49 (1.36; 1.64) per 1 SD higher plasma soluble E-selectin levels; 1.21(1.11; 1.31) per 1 SD higher plasma soluble intercellular adhesion molecule-1 levels; 1.48 (1.03; 2.12) per 1 SD lower response to acetylcholine-mediated peripheral vascular reactivity; 1.18 (1.08; 1.29) per 1 SD lower retinal arteriole-to-venule ratio; and 1.43 (1.33; 1.54) per 1 logarithmically transformed unit higher albumin-to-creatinine ratio. In addition, the pooled relative risks for incident impaired fasting glucose (409 cases) was 1.15 (1.01-1.31) per 1 SD greater retinal venular diameters. Conclusion-These data indicate that various estimates of microvascular dysfunction were associated with incident T2DM and, possibly, impaired fasting glucose, suggesting a role for the microcirculation in the pathogenesis of T2DM. (Arterioscler Thromb Vasc Biol. 2012;32:3082-3094.
On the Propagation of Reaction Fronts in a Sandy Aquifer Over 20+ Years: Lessons From a Test Site in Northwestern Germany
Despite reduction measures, nitrate and aluminum concentrations remain high in aquifers in northwestern Europe. To evaluate the effectiveness of groundwater protection policies, the long-term fate of these contaminants in groundwater needs to be understood. The groundwater catchment of the Haren water works, NW Germany, was characterized hydrogeochemically in the late 1990s, which provides an opportunity to study the solute fronts over a two-decade period and conduct a post-audit of the predicted front movement. Results indicate that, despite a significant reduction of the atmospheric acid loads, the acidification of soil and groundwater at the forest site persists. Removal of sorbed aluminum is required to induce a noticeable improvement, which will take at least several decades. The unexpected appearance of nitrate at the site, caused by a land use change in 1998, highlights the need for long-term monitoring. Core data at the agricultural site show that the denitrification front has moved very little between 1998 and 2017, in accordance with previous forecasts. Denitrification by-products, mainly sulfate and nitrogen, have migrated from the upper into the lower aquifer. A reactive transport model demonstrated how the link between the regional groundwater flow, pyrite oxidation, and the temporal variability of the nitrate concentration in recharge water, as reconstructed from age tracers, result in the observed vertical distribution of sulfate and nitrogen. This study demonstrates how long-term monitoring, aided by model-based data interpretation, can be used to successfully study and predict the fate of contaminants in groundwater. © 2021. The Authors
Microvascular dysfunction as a link between obesity, insulin resistance and hypertension
Impaired microvascular dilatation from any cause and impaired insulin-mediated capillary recruitment in particular result in suboptimal delivery of glucose and insulin to skeletal muscle, and subsequently impairment of glucose disposal (insulin resistance). In addition, microvascular dysfunction, through functional and/or structural arteriolar and capillary drop-out, and arteriolar constriction, increases peripheral resistance and thus blood pressure. Microvascular dysfunction may thus constitute a pathway that links insulin resistance and hypertension. Overweight and obesity may be an important cause of microvascular dysfunction. Mechanisms linking overweight and obesity to microvascular dysfunction include changes in the secretion of adipokines leading to increased levels of free fatty acids and inflammatory mediators, and decreased levels of adiponectin all of which may impair endothelial insulin signaling. Microvascular dysfunction may thus constitute a new treatment target in the prevention of type 2 diabetes mellitus and hypertension
IndustReal: A Dataset for Procedure Step Recognition Handling Execution Errors in Egocentric Videos in an Industrial-Like Setting
Although action recognition for procedural tasks has received notable
attention, it has a fundamental flaw in that no measure of success for actions
is provided. This limits the applicability of such systems especially within
the industrial domain, since the outcome of procedural actions is often
significantly more important than the mere execution. To address this
limitation, we define the novel task of procedure step recognition (PSR),
focusing on recognizing the correct completion and order of procedural steps.
Alongside the new task, we also present the multi-modal IndustReal dataset.
Unlike currently available datasets, IndustReal contains procedural errors
(such as omissions) as well as execution errors. A significant part of these
errors are exclusively present in the validation and test sets, making
IndustReal suitable to evaluate robustness of algorithms to new, unseen
mistakes. Additionally, to encourage reproducibility and allow for scalable
approaches trained on synthetic data, the 3D models of all parts are publicly
available. Annotations and benchmark performance are provided for action
recognition and assembly state detection, as well as the new PSR task.
IndustReal, along with the code and model weights, is available at:
https://github.com/TimSchoonbeek/IndustReal .Comment: Accepted for WACV 2024. 15 pages, 9 figures, including supplementary
material
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica – Part 3: Insights from Oligocene–Miocene TEX86-based sea surface temperature reconstructions
The volume of the Antarctic continental ice
sheet(s) varied substantially during the Oligocene and
Miocene ( 34–5 Ma) from smaller to substantially larger
than today, both on million-year and on orbital timescales.
However, reproduction through physical modeling of a dynamic
response of the ice sheets to climate forcing remains
problematic, suggesting the existence of complex feedback
mechanisms between the cryosphere, ocean, and atmosphere
systems. There is therefore an urgent need to improve the
models for better predictions of these systems, including resulting
potential future sea level change. To assess the interactions
between the cryosphere, ocean, and atmosphere,
knowledge of ancient sea surface conditions close to the
Antarctic margin is essential. Here, we present a new TEX86-
based sea surface water paleotemperature record measured
on Oligocene sediments from Integrated Ocean Drilling
Program (IODP) Site U1356, offshore Wilkes Land, East
Antarctica. The new data are presented along with previously
published Miocene temperatures from the same site.
Together the data cover the interval between 34 and
11 Ma and encompasses two hiatuses. This record allows us
to accurately reconstruct the magnitude of sea surface temperature
(SST) variability and trends on both million-year
and glacial–interglacial timescales.Julian D. Hartman, Francesca Sangiorgi,
Henk Brinkhuis, and Peter K. Bijl acknowledge the NWO Netherlands
Polar Program project number 866.10.110. Stefan Schouten
was supported by the Netherlands Earth System Science Centre
(NESSC), funded by the Dutch Ministry of Education, Culture
and Science (OCW). Peter K. Bijl and Francien Peterse received
funding through NWO-ALW VENI grant nos. 863.13.002 and
863.13.016, respectively. Carlota Escutia and Ariadna Salabarnada
thank the Spanish Ministerio de EconimÃa y Competitividad for
grant CTM2014-60451-C2-1-P. We thank Alexander Ebbing
and Anja Bruls for GDGT sample preparation during their MSc
research. This research used samples from the Integrated Ocean
Drilling Program (IODP). IODP was sponsored by the US National
Science Foundation and participating countries under management
of Joined Oceanographic Institutions Inc
Line Defects in Molybdenum Disulfide Layers
Layered molecular materials and especially MoS2 are already accepted as
promising candidates for nanoelectronics. In contrast to the bulk material, the
observed electron mobility in single-layer MoS2 is unexpectedly low. Here we
reveal the occurrence of intrinsic defects in MoS2 layers, known as inversion
domains, where the layer changes its direction through a line defect. The line
defects are observed experimentally by atomic resolution TEM. The structures
were modeled and the stability and electronic properties of the defects were
calculated using quantum-mechanical calculations based on the
Density-Functional Tight-Binding method. The results of these calculations
indicate the occurrence of new states within the band gap of the semiconducting
MoS2. The most stable non-stoichiometric defect structures are observed
experimentally, one of which contains metallic Mo-Mo bonds and another one
bridging S atoms
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