53 research outputs found
On the dependency of the electromechanical response of rotary MEMS/NEMS on their embedded flexure hinges' geometry
This paper investigates how the electromechanical response of MEMS/NEMS devices changes when the geometrical characteristics of their embedded flexural hinges are modified. The research is dedicated particularly to MEMS/NEMS devices which are actuated by means of rotary comb-drives. The electromechanical behavior of a chosen rotary device is assessed by studying the rotation of the end effector, the motion of the comb-drive mobile fingers, the actuator’s maximum operating voltage, and the stress sustained by the flexure when the flexure’s shape, length, and width change. The results are compared with the behavior of a standard revolute joint. Outcomes demonstrate that a linear flexible beam cannot perfectly replace the revolute joint as it induces a translation that strongly facilitates the pull-in phenomenon and significantly increases the risk of ruptures of the comb-drives. On the other hand, results show how curved beams provide a motion that better resembles the revolute motion, preserving the structural integrity of the device and avoiding the pull-in phenomenon. Finally, results also show that the end effector motion approaches most precisely the revolute motion when a fine tuning of the beam’s length and width is performed
U-shaped relationship between vitamin D levels and long-term outcome in large cohort of survivors of acute myocardial infarction
Background: Previous studies in the setting of patients with acute myocardial infarction (AMI) have demonstrated that hypovitaminosis D is associated with increased mortality risk during a follow-up whose median did not
exceed two years.
Objective: To evaluate the impact of vitamin D levels on long-term mortality in patients with AMI.
Results: In our study 477 patients with AMI were included. During a median follow-up period of 57 (IQR 53\u201364) months, 93 patients (20%) died. A non-linear U-shaped relationship between 25(OH)D levels and long-term
mortality was observed; patients with vitamin D b 10 ng/mL and N30 ng/mL had higher mortality rate than those with intermediate values. After adjustment for differences in baseline features and treatment, it was con-
firmed that extreme values of vitamin D (b10 or N30 ng/mL) are independent predictors of mortality with HR of 3.02 (95% CI 1.78\u20135.11). Other independent predictors of outcome were age, NYHA class at discharge, treatment
with ACE inhibitors and statins. The estimated time-dependent ROC curve of the multivariable model including
vitamin D showed an AUC significantly higher than the model without vitamin D: AUC 0.82 (95% CI 0.76\u20130.87) vs. 0.77 (95% CI 0.71\u20130.83), p = 0.005. Addition of vitamin D to the model that included all significant factors for
mortality improved the prognostic accuracy as showed by the metrics of reclassification (NRI 0.34 (95% CI 0.14\u20130.48), p = 0.003 and IDI 0.06 (95% CI 0.01\u20130.12, p = 0.005 p = 0.03).
Conclusions: We report a U-shaped relationship between vitamin D levels and long-term outcome of patients
surviving AMI
Multicomponent Antibiofilm Lipid Nanoparticles as Novel Platform to Ameliorate Resveratrol Properties: Preliminary Outcomes on Fibroblast Proliferation and Migration
: The well-being of skin and mucous membranes is fundamental for the homeostasis of the body and thus it is imperative to treat any lesion quickly and correctly. In this view, polyphenols might assist and enhance a successful wound healing process by reducing the inflammatory cascade and the production of free radicals. However, they suffer from disadvantageous physico-chemical properties, leading to restricted clinical use. In this work, a complex mixture of PEGylated lipid, Glyceryl monoester, 18-β-Glycyrrhetinic Acid and Menthol was designed to entrap Resveratrol (RSV) as the active ingredient and further produce lipid nanoparticles (LNPs) by homogenization followed by high-frequency sonication. The nanosystem was properly characterized in terms of particle size (DLS, SEM), zeta potential, drug loading, antioxidant power (DPPH), release behaviour, cytocompatibility, wound healing and antibiofilm properties. The optimized lipid mixture was homogeneous, melted at 57-61 °C and encapsulated amorphous RSV (4.56 ± 0.04% w/w). The RSV-loaded LNPs were almost monodispersed (PDI: 0.267 ± 0.010), with nanometric size (162.86 ± 3.12 nm), scavenger properties and suitable DR% and LE% values (96.82 ± 1.34% and 95.17 ± 0.25%, respectively). The release studies were performed to simulate the wound conditions: 1-octanol to mimic the lipophilic domains of biological tissues (where the First Order kinetic was observed) and citrate buffer pH 5.5 according to the inflammatory wound exudate (where the Korsmeyer-Peppas kinetic was followed). The biological and microbiological evaluations highlighted fibroblast proliferation and migration effects as well as antibiofilm properties at extremely low doses (LNPs: 22 μg/mL, corresponding to RSV 5 µM). Thus, the proposed multicomponent LNPs could represent a valuable RSV delivery platform for wound healing purposes
IGF-I induces upregulation of DDR1 collagen receptor in breast cancer cells by suppressing MIR-199a-5p through the PI3K/AKT pathway.
Discoidin Domain Receptor 1 (DDR1) is a collagen receptor tyrosine-kinase that contributes to epithelial-to-mesenchymal transition and enhances cancer progression. Our previous data indicate that, in breast cancer cells, DDR1 interacts with IGF-1R and positively modulates IGF-1R expression and biological responses, suggesting that the DDR1-IGF-IR cross-talk may play an important role in cancer.In this study, we set out to evaluate whether IGF-I stimulation may affect DDR1 expression. Indeed, in breast cancer cells (MCF-7 and MDA-MB-231) IGF-I induced significant increase of DDR1 protein expression, in a time and dose dependent manner. However, we did not observe parallel changes in DDR1 mRNA. DDR1 upregulation required the activation of the PI3K/AKT pathway while the ERK1/2, the p70/mTOR and the PKC pathways were not involved. Moreover, we observed that DDR1 protein upregulation was induced by translational mechanisms involving miR-199a-5p suppression through PI3K/AKT activation. This effect was confirmed by both IGF-II produced by cancer-associated fibroblasts from human breast cancer and by stable transfection of breast cancer cells with a human IGF-II expression construct. Transfection with a constitutively active form of AKT was sufficient to decrease miR-199a-5p and upregulate DDR1. Accordingly, IGF-I-induced DDR1 upregulation was inhibited by transfection with pre-miR-199a-5p, which also impaired AKT activation and cell migration and proliferation in response to IGF-I.These results demonstrate that, in breast cancer cells, a novel pathway involving AKT/miR-199a-5p/DDR1 plays a role in modulating IGFs biological responses. Therefore, this signaling pathway may represent an important target for breast cancers with over-activation of the IGF-IR axis
P-MaNGA : full spectral fitting and stellar population maps from prototype observations
MC acknowledges support from a Royal Society University Research Fellowship.MaNGA (Mapping Nearby Galaxies at Apache Point Observatory) is a 6-yearSDSS-IV survey that will obtain resolved spectroscopy from 3600 Å to10300 Å for a representative sample of over 10,000 nearby galaxies.In this paper, we derive spatially resolved stellar population properties and radial gradients by performing full spectral fitting of observed galaxy spectra from P-MaNGA, a prototype of the MaNGA instrument. These data include spectra for eighteen galaxies, covering a large range of morphological type. We derive age, metallicity, dust and stellar mass maps, and their radial gradients, using high spectral-resolution stellar population models, and assess the impact of varying the stellar library input to the models. We introduce a method to determine dust extinction which is able to give smooth stellar mass maps even in cases of high and spatially non-uniform dust attenuation.With the spectral fitting we produce detailed maps of stellar population properties which allow us to identify galactic features among this diverse sample such as spiral structure, smooth radial profiles with little azimuthal structure in spheroidal galaxies, and spatially distinct galaxy sub-components. In agreement with the literature, we find the gradients for galaxies identified as early-type to be on average flat in age, and negative (- 0.15 dex / Re ) in metallicity,whereas the gradients for late-type galaxies are on average negative in age (- 0.39 dex / Re ) and flat in metallicity. We demonstrate howdifferent levels of data quality change the precision with which radialgradients can be measured. We show how this analysis, extended to thelarge numbers of MaNGA galaxies, will have the potential to shed lighton galaxy structure and evolution.PostprintPeer reviewe
The impact of COVID-19 on myocardial infarctions, strokes and out-of-hospital cardiopulmonary arrests: an observational retrospective study on time-sensitive disorders in the Friuli Venezia Giulia region (Italy)
The COVID-19 global pandemic has changed considerably the way time-sensitive disorders are treated. Home isolation, people's fear of contracting the virus and hospital reorganisation have led to a significant decrease in contacts between citizens and the healthcare system, with an expected decrease in calls to the Emergency Medical Services (EMS) of the Friuli-Venezia Giulia (FVG) region. However, mortality in clinical emergencies like acute ST-elevation myocardial infarction (STEMI), stroke and out-of-hospital cardiopulmonary arrest (OHCA) remained high. An observational retrospective cross-sectional study was carried out in FVG, taking into account the period between March 1, 2020, and May 31, 2020, the first wave of the COVID-19 pandemic, and comparing it with the same period in 2019. The flow of calls to the EMS was analysed and COVID-19 impact on time-sensitive disorders (STEMIs, ischemic strokes and OHCPAs) was measured in terms of hospitalisation, treatment and mortality. Despite a -8.01% decrease (p value ˂0.001) in emergency response, a 10.89% increase in calls to the EMS was observed. A lower number of advanced cardiopulmonary resuscitations (CPR) (75.8 vs 45.2%, p=0.000021 in April) and ROSC (39.1 vs 11.6%, p=0.0001 in April) was remarked, and survival rate dropped from 8.5 to 5%. There were less strokes (-27.5%, p value=0.002) despite a more severe onset of symptoms at hospitalisation with NHISS˃10 in 38.47% of cases. Acute myocardial infarctions decreased as well (-20%, p value=0.05), but statistical significances were not determined in the variables considered and in mortality. Despite a lower number of emergency responses, the number of calls to the EMS was considerably higher. The number of cardiac arrests treated with advanced CPR (ALS) was lower, but mortality was higher. The number of strokes decreased as well, but at the time of hospitalisation the clinical picture of the patient was more severe, thus affecting the outcome when the patient was discharged. Finally, STEMI patients decreased; however, no critical issues were observed in the variables taken into account, neither in terms of response times nor in terms of treatment times
Molecular Characterisation of Long-Acting Insulin Analogues in Comparison with Human Insulin, IGF-1 and Insulin X10
AIMS/HYPOTHESIS: There is controversy with respect to molecular characteristics of insulin analogues. We report a series of experiments forming a comprehensive characterisation of the long acting insulin analogues, glargine and detemir, in comparison with human insulin, IGF-1, and the super-mitogenic insulin, X10. METHODS: We measured binding of ligands to membrane-bound and solubilised receptors, receptor activation and mitogenicity in a number of cell types. RESULTS: Detemir and glargine each displayed a balanced affinity for insulin receptor (IR) isoforms A and B. This was also true for X10, whereas IGF-1 had a higher affinity for IR-A than IR-B. X10 and glargine both exhibited a higher relative IGF-1R than IR binding affinity, whereas detemir displayed an IGF-1R:IR binding ratio of ≤ 1. Ligands with high relative IGF-1R affinity also had high affinity for IR/IGF-1R hybrid receptors. In general, the relative binding affinities of the analogues were reflected in their ability to phosphorylate the IR and IGF-1R. Detailed analysis revealed that X10, in contrast to the other ligands, seemed to evoke a preferential phosphorylation of juxtamembrane and kinase domain phosphorylation sites of the IR. Sustained phosphorylation was only observed from the IR after stimulation with X10, and after stimulation with IGF-1 from the IGF-1R. Both X10 and glargine showed an increased mitogenic potency compared to human insulin in cells expressing many IGF-1Rs, whereas only X10 showed increased mitogenicity in cells expressing many IRs. CONCLUSIONS: Detailed analysis of receptor binding, activation and in vitro mitogenicity indicated no molecular safety concern with detemir
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
The Fifteenth Data Release of the Sloan Digital Sky Surveys: First Release of MaNGA-derived Quantities, Data Visualization Tools, and Stellar Library
Twenty years have passed since first light for the Sloan Digital Sky Survey (SDSS). Here, we release data taken by the fourth phase of SDSS (SDSS-IV) across its first three years of operation (2014 July–2017 July). This is the third data release for SDSS-IV, and the 15th from SDSS (Data Release Fifteen; DR15). New data come from MaNGA—we release 4824 data cubes, as well as the first stellar spectra in the MaNGA Stellar Library (MaStar), the first set of survey-supported analysis products (e.g., stellar and gas kinematics, emission-line and other maps) from the MaNGA Data Analysis Pipeline, and a new data visualization and access tool we call "Marvin." The next data release, DR16, will include new data from both APOGEE-2 and eBOSS; those surveys release no new data here, but we document updates and corrections to their data processing pipelines. The release is cumulative; it also includes the most recent reductions and calibrations of all data taken by SDSS since first light. In this paper, we describe the location and format of the data and tools and cite technical references describing how it was obtained and processed. The SDSS website (www.sdss.org) has also been updated, providing links to data downloads, tutorials, and examples of data use. Although SDSS-IV will continue to collect astronomical data until 2020, and will be followed by SDSS-V (2020–2025), we end this paper by describing plans to ensure the sustainability of the SDSS data archive for many years beyond the collection of data
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