261 research outputs found
Surfactant behavior of sodium dodecylsulfate in deep eutectic solvent choline chloride/urea
Deep eutectic solvents (DES) resemble ionic liquids but are formed from an ionic mixture instead of being a single ionic compound. Here we present some results that demonstrate that surfactant sodium dodecyl sulfate (SDS) remains surface-active and shows self-assembly phenomena in the most commonly studied DES, choline chloride/urea. X-ray reflectivity (XRR) and small angle neutron scattering (SANS) suggest that the behavior is significantly different from that in water. Our SANS data supports our determination of the critical micelle concentration using surface-tension measurements and suggests that the micelles formed in DES do not have the same shape and size as those seen in water. Reflectivity measurements have also demonstrated that the surfactants remain surface-active below this concentration
Improving splenic conservation rate after trauma by applying a protocol for non-operative management and follow-up: A propensity-score analysis
Background: There are shared guidelines about Non-Operative Management (NOM) of splenic injuries, but some unanswered questions remain. The aim of the present study is to establish the usefulness of a standardized protocol for management and follow-up of NOM patients with splenic injuries. Methods: Multicenter retrospective observational study including patients with major blunt trauma (ISS.15) with splenic injuries managed between January 1st 2014 and December 31st 2016 in two Italian I level Trauma Centers: one with a standardized management and follow-up protocol for NOM (Bufalini Hospital, Cesena, BH), and the other without it (ASST Papa Giovanni XXIII Hospital, Bergamo, PG23H). Comparison between patients' outcomes were performed and a propensity score model was calculated. Results: 47 patients managed in BH and 49 patients in PG23H were included. In BH, a higher proportion of patients was treated with NOM (72.3 % vs. 53.1 %, p ¼ 0.051). There was no difference in complication rate and mortality in patients treated with NOM in the two hospitals. A borderline significant trend to a higher NOM failure rate in PG23H was found (BH 0.0 % vs. PG23H 11.3 %, p ¼ 0.076). The total splenic conservation rate was significantly higher in BH (BH 72.3 % vs. PG23H 46.9 %, p ¼ 0.011). After the Propensity Score based matching, 72 patients were included and the total splenic conservation rate was significantly higher in BH (BH: 77.8 % vs. PG23H: 50.9 %, p ¼ 0.014). Conclusions: The application of a protocol for in-hospital management and follow-up for NOM of patients with splenic injury could decrease the NOM failure rate and improve splenic conservation rate
LANCL1 binds abscisic acid and stimulates glucose transport and mitochondrial respiration in muscle cells via the AMPK/PGC-1α/Sirt1 pathway
Objective: Abscisic acid (ABA) is a plant hormone also present and active in animals. In mammals, ABA regulates blood glucose levels by stimulating insulin-independent glucose uptake and metabolism in adipocytes and myocytes through its receptor LANCL2. The objective of this study was to investigate whether another member of the LANCL protein family, LANCL1, also behaves as an ABA receptor and, if so, which functional effects are mediated by LANCL1. Methods: ABA binding to human recombinant LANCL1 was explored by equilibrium-binding experiments with [3H]ABA, circular dichroism, and surface plasmon resonance. Rat L6 myoblasts overexpressing either LANCL1 or LANCL2, or silenced for the expression of both proteins, were used to investigate the basal and ABA-stimulated transport of a fluorescent glucose analog (NBDG) and the signaling pathway downstream of the LANCL proteins using Western blot and qPCR analysis. Finally, glucose tolerance and sensitivity to ABA were compared in LANCL2−/− and wild-type (WT) siblings. Results: Human recombinant LANCL1 binds ABA with a Kd between 1 and 10 μM, depending on the assay (i.e., in a concentration range that lies between the low and high-affinity ABA binding sites of LANCL2). In L6 myoblasts, LANCL1 and LANCL2 similarly, i) stimulate both basal and ABA-triggered NBDG uptake (4-fold), ii) activate the transcription and protein expression of the glucose transporters GLUT4 and GLUT1 (4-6-fold) and the signaling proteins AMPK/PGC-1α/Sirt1 (2-fold), iii) stimulate mitochondrial respiration (5-fold) and the expression of the skeletal muscle (SM) uncoupling proteins sarcolipin (3-fold) and UCP3 (12-fold). LANCL2−/− mice have a reduced glucose tolerance compared to WT. They spontaneously overexpress LANCL1 in the SM and respond to chronic ABA treatment (1 μg/kg body weight/day) with an improved glycemia response to glucose load and an increased SM transcription of GLUT4 and GLUT1 (20-fold) of the AMPK/PGC-1α/Sirt1 pathway and sarcolipin, UCP3, and NAMPT (4- to 6-fold). Conclusions: LANCL1 behaves as an ABA receptor with a somewhat lower affinity for ABA than LANCL2 but with overlapping effector functions: stimulating glucose uptake and the expression of muscle glucose transporters and mitochondrial uncoupling and respiration via the AMPK/PGC-1α/Sirt1 pathway. Receptor redundancy may have been advantageous in animal evolution, given the role of the ABA/LANCL system in the insulin-independent stimulation of cell glucose uptake and energy metabolism
A Robust Mechanical Sensing System for Unmanned Sea Surface Vehicles
The need for autonomous navigation and intelligent control of unmanned sea surface vehicles requires a mechanically robust sensing architecture that is watertight, durable, and insensitive to vibration and shock loading. The sensing system developed here comprises four black and white cameras and a single color camera. The cameras are rigidly mounted to a camera bar that can be reconfigured to mount multiple vehicles, and act as both navigational cameras and application cameras. The cameras are housed in watertight casings to protect them and their electronics from moisture and wave splashes. Two of the black and white cameras are positioned to provide lateral vision. They are angled away from the front of the vehicle at horizontal angles to provide ideal fields of view for mapping and autonomous navigation. The other two black and white cameras are positioned at an angle into the color camera's field of view to support vehicle applications. These two cameras provide an overlap, as well as a backup to the front camera. The color camera is positioned directly in the middle of the bar, aimed straight ahead. This system is applicable to any sea-going vehicle, both on Earth and in space
An overview of the NIRSPEC upgrade for the Keck II telescope
NIRSPEC is a 1-5 micron echelle spectrograph in use on the Keck II Telescope
since 1999. The spectrograph is capable of both moderate (R~2,000) and high
(R~25,000) resolution observations and has been a workhorse instrument across
many astronomical fields, from planetary science to extragalactic observations.
In the latter half of 2018, we will upgrade NIRSPEC to improve the sensitivity
and stability of the instrument and increase its lifetime. The major components
of the upgrade include replacing the spectrometer and slit-viewing camera
detectors with Teledyne H2RG arrays and replacing all transputer-based
electronics. We present detailed design, testing, and analysis of the upgraded
instrument, including the finalized optomechanical design of the new 1-5 micron
slit-viewing camera, final alignment and assembly of the science array,
electronics systems, and updated software design.Comment: Proceedings of the 2018 SPIE Astronomical Telescopes &
Instrumentatio
Design and development of MOSFIRE: the Multi-Object Spectrometer For Infra-Red Exploration at the Keck Observatory
MOSFIRE is a unique multi-object spectrometer and imager for the Cassegrain focus of the 10 m Keck 1 telescope. A refractive optical design provides near-IR (0.97 to 2.45 μm) multi-object spectroscopy over a 6.14' x 6.14' field of view with a resolving power of R~3,270 for a 0.7" slit width (2.9 pixels in the dispersion direction), or imaging over a field of view of 6.8' diameter with 0.18" per pixel sampling. A single diffraction grating can be set at two fixed angles, and order-sorting filters provide spectra that cover the K, H, J or Y bands by selecting 3rd, 4th, 5th or 6th order respectively. A folding flat following the field lens is equipped with piezo transducers to provide tip/tilt control for flexure compensation at the 0.1 pixel level. A special feature of MOSFIRE is that its multiplex advantage of up to 46 slits is achieved using a cryogenic Configurable Slit Unit or CSU developed in collaboration with the Swiss Centre for Electronics and Micro Technology (CSEM). The CSU is reconfigurable under remote control in less than 5 minutes without any thermal cycling of the instrument. Slits are formed by moving opposable bars from both sides of the focal plane. An individual slit has a length of 7.1" but bar positions can be aligned to make longer slits. When masking bars are removed to their full extent and the grating is changed to a mirror, MOSFIRE becomes a wide-field imager. Using a single, ASIC-driven, 2K x 2K H2-RG HgCdTe array from Teledyne Imaging Sensors with exceptionally low dark current and low noise, MOSFIRE will be extremely sensitive and ideal for a wide range of science applications. This paper describes the design and testing of the instrument prior to delivery later in 2010
How consistent are the transcriptome changes associated with cold acclimation in two species of the Drosophila virilis group?
This work was financially support by a Marie Curie Initial Training Network grant, “Understanding the evolutionary origin of biological diversity” (ITN-2008–213780 SPECIATION), grants from the Academy of Finland to A.H. (project 132619) and M.K. (projects 268214 and 272927), a grant from NERC, UK to M.G.R. (grant NE/J020818/1), and NERC, UK PhD studentship to D.J.P. (NE/I528634/1).For many organisms the ability to cold acclimate with the onset of seasonal cold has major implications for their fitness. In insects, where this ability is widespread, the physiological changes associated with increased cold tolerance have been well studied. Despite this, little work has been done to trace changes in gene expression during cold acclimation that lead to an increase in cold tolerance. We used an RNA-Seq approach to investigate this in two species of the Drosophila virilis group. We found that the majority of genes that are differentially expressed during cold acclimation differ between the two species. Despite this, the biological processes associated with the differentially expressed genes were broadly similar in the two species. These included: metabolism, cell membrane composition, and circadian rhythms, which are largely consistent with previous work on cold acclimation/cold tolerance. In addition, we also found evidence of the involvement of the rhodopsin pathway in cold acclimation, a pathway that has been recently linked to thermotaxis. Interestingly, we found no evidence of differential expression of stress genes implying that long-term cold acclimation and short-term stress response may have a different physiological basis.PostprintPeer reviewe
Microvascular changes in renal allografts associated with FK506 (Tacrolimus) therapy
FK506 (Tacrolimus) recently has been shown to be an effective immunosuppressant after renal transplantation. It is associated with less hypertension, hypercholesterolemia and steroid use compared with cyclosporine. We report 10 patients on FK506 who showed fibrin thrombi within the glomerular capillaries and/or arterioles at renal allograft biopsy. These biopsies were generally performed to assess increasing serum creatinine levels; laboratory evidence of hemolytic uremic syndrome was present in one instance. Plasma or whole blood FK506 levels were elevated in eight of 10 cases. Reduction of immunosuppression led to clinical improvement or biopsy- proven resolution of thrombi in all cases. These observations suggest that FK506 may occasionally produce microvascular changes in the renal allograft. The estimated incidence of this occurrence (1%) is comparable with that reported with cyclosporine (3%)
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