2,156 research outputs found
Effect of COVID-19 Pandemic on Mechanical Thrombectomy for Acute Ischemic Stroke Treatment in United States
There is accumulating data suggesting that the ischemic stroke may be increased in patients with corona virus disease 2019 (COVID-19) due to hyper coagulopathy. An increase in acute ischemic stroke patients who require mechanical thrombectomy is to be expected particularly in regions with high rates of COVID-19
Correlating activity and defects in (photo)electrocatalysts using in-situ transient optical microscopy
(Photo)electrocatalysts capture sunlight and use it to drive chemical
reactions such as water splitting to produce H2. A major factor limiting
photocatalyst development is their large heterogeneity which spatially
modulates reactivity and precludes establishing robust structure-function
relationships. To make such links requires simultaneously probing of the
electrochemical environment at microscopic length scales (nm to um) and broad
timescales (ns to s). Here, we address this challenge by developing and
applying in-situ steady-state and transient optical microscopies to directly
map and correlate local electrochemical activity with hole lifetimes, oxygen
vacancy concentration and the photoelectrodes crystal structure. Using this
combined approach alongside spatially resolved X-Ray absorption measurements,
we study microstructural and point defects in prototypical hematite (Fe2O3)
photoanodes. We demonstrate that regions of Fe2O3, adjacent to microstructural
cracks have a better photoelectrochemical response and reduced back electron
recombination due to an optimal oxide vacancy concentration, with the film
thickness and carbon impurities also dramatically influencing activity in a
complex manner. Our work highlights the importance of microscopic mapping to
understand activity and the impact of defects in even, seemingly, homogeneous
solid-state metal oxide photoelectrodes
Increase of the Adiponectin/Leptin Ratio in Patients with Obesity and Type 2 Diabetes after Roux-en-Y Gastric Bypass
Bariatric surgery remains the most effective option for achieving important and sustained weight loss. We explored the effects of Roux-en-Y gastric bypass (RYGB) on the circulating levels of adiponectin, leptin, and the adiponectin/leptin (Adpn/Lep) ratio in patients with obesity and type 2 diabetes (T2D). Twenty-five T2D volunteers undergoing RYGB were included in the study, and further subclassified as patients that responded or not to RYBG, regarding remission of T2D. Anthropometric and biochemical variables were evaluated before and after RYGB. Obese patients with T2D exhibited an increase (p < 0.0001) in the Adpn/Lep ratio after RYGB. Changes in the Adpn/Lep ratio correlated better with changes in anthropometric data (p < 0.001) than with the variations of adiponectin or leptin alone. Multiple regression analysis revealed that the change in the Adpn/Lep ratio in patients with T2D was an independent predictor of the changes in body mass index (p < 0.001) and body fat percentage (p = 0.022). However, the Adpn/Lep ratio did not differ between individuals with or without T2D remission after RYGB. In summary, the current study demonstrated that after weight and body fat loss following RYGB, the Adpn/Lep ratio increased in patients with obesity and T2D
GLP-1 limits adipocyte inflammation and its low circulating pre-operative concentrations predict worse type 2 diabetes remission after bariatric surgery in obese patients
Objective: Glucagon-like peptide (GLP)-1 has been proposed as a key candidate in glucose
improvements after bariatric surgery. Our aim was to explore the role of GLP-1 in surgically-induced
type 2 diabetes (T2D) improvement and its capacity to regulate human adipocyte inflammation.
Methods: Basal circulating concentrations of GLP-1 as well as during an oral glucose tolerance test
(OGTT) were measured in lean and obese volunteers with and without T2D (n = 93). In addition,
GLP-1 levels were determined before and after weight loss achieved by Roux-en-Y gastric bypass
(RYGB) (n = 77). The impact of GLP-1 on inflammation signalling pathways was also evaluated.
Results: We show that the reduced (p < 0.05) circulating levels of GLP-1 in obese T2D patients
increased (p < 0.05) after RYGB. The area under the curve was significantly lower in obese patients
with (p < 0.01) and without (p < 0.05) T2D compared to lean volunteers while obese patients with
T2D exhibited decreased GLP-1 levels at baseline (p < 0.05) and 120 min (p < 0.01) after the OGTT.
Importantly, higher (p < 0.05) pre-operative GLP-1 concentrations were found in patients with
T2D remission after RYGB. We also revealed that exendin-4, a GLP-1 agonist, downregulated the
expression of inflammation-related genes (IL1B, IL6, IL8, TNF) and, conversely, upregulated the
mRNA levels of ADIPOQ in human visceral adipocytes. Furthermore, exendin-4 blocked (p < 0.05)
LPS-induced inflammation in human adipocytes via downregulating the expression and secretion of
key inflammatory markers. Conclusions: Our data indicate that GLP-1 may contribute to glycemic
control and exert a role in T2D remission after RYGB. GLP-1 is also involved in limiting inflammation
in human visceral adipocytes
The scattering of SH waves by a finite crack with a superposition based diffraction technique
The problem of diffraction of cylindrical and plane SH waves by a finite crack is revisited -- We construct an approximate solution by the addition of independent diffracted terms -- We start with the derivation of the fundamental case of a semi-infinite crack obtained as a degenerate case of generalized wedge -- This building block is then used to compute the diffraction of the main incident waves -- The interaction between the opposite edges of the crack is then considered one term at a time until a desired tolerance is reached -- We propose a recipe to determine the number of required interactions as a function of frequency -- The solution derived with the superposition technique can be applied at low and high frequencie
Arterial Stiffness: Its Relation with Prediabetes and Metabolic Syndrome and Possible Pathogenesis
Aims: To evaluate arterial stiffness indicators in people with prediabetes (PreD) and its possible pathogenesis. Materials and methods: Pulse wave velocity (PWV) was measured in 208 people with FINDRISC ≥ 13 (57 ± 8 years old, 68.7% women) and thereafter divided into those having either normal glucose tolerance (NGT) or PreD. In each subgroup we also identified those with/out insulin resistance (IR) measured by the triglyceride/HDL-c ratio (normal cut off values previously established in our population). Clinical and metabolic data were collected for all participants. PWV was compared between subgroups using independent t test. Results: Women and men had comparable clinical and metabolic characteristics with obesity (BMI ≥ 30) and antihypertensive-statin treatment, almost half with either NGT or PreD. Whereas 48% of NGT people presented IR (abnormally high TG/HDL-c ratio), 52% had PreD. PWV was significantly higher only in those with a complete picture of metabolic syndrome (MS). Conclusions: Since PWV was significantly impaired in people with a complete picture of MS, clinicians must carefully search for early diagnosis of this condition and prescribe a healthy life-style to prevent development/progression of CVD. This proactive attitude would provide a cost-effective preventive strategy to avoid CVD’s negative impact on patients’ quality of life and on health systems due to their higher care costs.Centro de Endocrinología Experimental y AplicadaFacultad de Ciencias Médica
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
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