558 research outputs found
An Updated Line List for Spectroscopic Investigation of G Stars- I: Redetermination of the Abundances in the Solar Photosphere
We propose a line list that may be useful for the abundance analysis of
G-type stars in the wavelength range 4080 -- 6780 A. It is expected that the
line list will be useful for surveys/libraries with overlapping spectral
regions (e.g. ELODIE/SOPHIE libraries, UVES-580 setting of Gaia-ESO), and in
particular for the analysis of F- and G-type stars in general. The atomic data
are supplemented by detailed references to the sources. We estimated the Solar
abundances using stellar lines and the high-resolution Kitt Peak National
Observatory (KPNO) spectra of the Sun to determine the uncertainty in the log
gf values. By undertaking a systematic search that makes use of the lower
excitation potential and gf-values and using revised multiplet table as an
initial guide, we identified 363 lines of 24 species that have accurate
gf-values and are free of blends in the spectra of the Sun and a Solar analogue
star, HD 218209 (G6V), for which accurate and up-to-date abundances were
obtained from both ELODIE and PolarBASE spectra of the star. For the common
lines with the Gaia-ESO line list v.6 provided by the Gaia-ESO collaboration,
we discovered significant inconsistencies in the gf-values for certain lines of
varying species.Comment: 17 pages, 4 figures and 5 tables, accepted for publication in Physics
and Astronomy Report
Alien species on the coasts of Turkey
The compilation of data on alien species reported from the Turkish coasts yielded a total of 263 species belonging to 11 systematic groups, of which Mollusca had the highest number of species (85 species), followed by Crustacea (51), fishes (43) and phytobenthos (39). The Black Sea is represented by a total of 20 alien species, the Sea of Marmara by 48 species, the Aegean Sea by 98 species and the Levantine Sea by 202 species. The majority of aliens found in the Black Sea and the Sea of Marmara were transported via shipping, whereas the Levantine coast is extensively subjected to Lessepsian migration. Benthic habitats (soft and hard substrata) comprise 76% of the total alien species and the pelagic environment is inhabited by thirty-nine species. Almost 50% of aliens collected from the Turkish coasts were found only at 0-10 m depth. Eight species occur at depths deeper than 100 m. The impacts of aliens on the benthic and pelagic ecosystems are presented
Hybrid inhibitor of peripheral cannabinoid-1 receptors and inducible nitric oxide synthase mitigates liver fibrosis
Liver fibrosis, a consequence of chronic liver injury and a way station to cirrhosis and hepatocellular carcinoma, lacks effective treatment. Endocannabinoids acting via cannabinoid-1 receptors (CB1R) induce profibrotic gene expression and promote pathologies that predispose to liver fibrosis. CB1R antagonists produce opposite effects, but their therapeutic development was halted due to neuropsychiatric side effects. Inducible nitric oxide synthase (iNOS) also promotes liver fibrosis and its underlying pathologies, but iNOS inhibitors tested to date showed limited therapeutic efficacy in inflammatory diseases. Here, we introduce a peripherally restricted, orally bioavailable CB1R antagonist, which accumulates in liver to release an iNOS inhibitory leaving group. In mouse models of fibrosis induced by CCl4 or bile duct ligation, the hybrid CB1R/iNOS antagonist surpassed the antifibrotic efficacy of the CB1R antagonist rimonabant or the iNOS inhibitor 1400W, without inducing anxiety-like behaviors or CB1R occupancy in the CNS. The hybrid inhibitor also targeted CB1R-independent, iNOS-mediated profibrotic pathways, including increased PDGF, Nlrp3/Asc3, and integrin alphavbeta6 signaling, as judged by its ability to inhibit these pathways in cnr1-/- but not in nos2-/- mice. Additionally, it was able to slow fibrosis progression and to attenuate established fibrosis. Thus, dual-target peripheral CB1R/iNOS antagonists have therapeutic potential in liver fibrosis
Physical activity, BMI and oral health behaviour among adolescents: Finnish School Health Promotion Study
To assess associations between oral health behaviour and physical activity and related factors among adolescents.\nThe study population (n = 76 529) consisted of a representative sample of 16- to 18-year-old Finnish adolescents (boys: 37 211, girls: 39 318). An anonymous, confidential and voluntary classroom-administered questionnaire included questions about tooth brushing frequency, physical activity, BMI and eating habits. Moderate-to-vigorous physical activity (MVPA) was used to assess the adolescents' physical activity. The chi-square test and multiple binary logistic regression were used for statistical analyses. Adjusted odds ratios (OR) and their 95% confidence intervals (CI) were calculated for MVPA, BMI, breakfast, smoking and socioeconomic factors as parents' education and school type.\nThe prevalence of twice daily tooth brushing was highest among adolescents reporting 4 hours or more of MVPA (51-77%). Obese and smoking adolescents exercised less often than normal weighted and non-smokers. Girls brushed their teeth twice daily significantly more often than boys (P < 0.001), and high-school students brushed their teeth significantly more often than vocational school students (P < 0.001). Logistic regression models showed that obesity (OR = 2.14, 95% CI 1.92-2.37) and irregular breakfast eating (OR = 2.35, 95% CI 2.19-2.52) among boys, and obesity (OR = 2.81, 95% CI 2.48-3.17), physical inactivity (OR = 1.89, 95% CI 1.78-2.00) and irregular breakfast eating (OR = 1.91, 95% CI 1.79-2.04) among girls were strong predictors for poor tooth brushing.\nPhysically active adolescents had better oral health behaviour than less active adolescents. Obesity and smoking were associated with infrequent tooth brushing.\nBackground\nMethods\nResults\nConclusion
Amyloid Inspired Self-Assembled Peptide Nanofibers
Cataloged from PDF version of article.Amyloid peptides are important components in many degenerative
diseases as well as in maintaining cellular metabolism. Their unique stable structure
provides new insights in developing new materials. Designing bioinspired selfassembling
peptides is essential to generate new forms of hierarchical nanostructures.
Here we present oppositely charged amyloid inspired peptides (AIPs),
which rapidly self-assemble into nanofibers at pH 7 upon mixing in water caused
by noncovalent interactions. Mechanical properties of the gels formed by selfassembled
AIP nanofibers were analyzed with oscillatory rheology. AIP gels
exhibited strong mechanical characteristics superior to gels formed by self-assembly
of previously reported synthetic short peptides. Rheological studies of gels
composed of oppositely charged mixed AIP molecules (AIP-1 + 2) revealed superior mechanical stability compared to individual
peptide networks (AIP-1 and AIP-2) formed by neutralization of net charges through pH change. Adhesion and elasticity
properties of AIP mixed nanofibers and charge neutralized AIP-1, AIP-2 nanofibers were analyzed by high resolution force−
distance mapping using atomic force microscopy (AFM). Nanomechanical characterization of self-assembled AIP-1 + 2, AIP-1,
and AIP-2 nanofibers also confirmed macroscopic rheology results, and mechanical stability of AIP mixed nanofibers was higher
compared to individual AIP-1 and AIP-2 nanofibers self-assembled at acidic and basic pH, respectively. Experimental results were
supported with molecular dynamics simulations by considering potential noncovalent interactions between the amino acid
residues and possible aggregate forms. In addition, HUVEC cells were cultured on AIP mixed nanofibers at pH 7 and biocompatibility
and collagen mimetic scaffold properties of the nanofibrous system were observed. Encapsulation of a zwitterionic
dye (rhodamine B) within AIP nanofiber network was accomplished at physiological conditions to demonstrate that this network
can be utilized for inclusion of soluble factors as a scaffold for cell culture studies. Copyright © 2012 American Chemical Societ
Feasibility of time-lapse seismic methodology for monitoring the injection of small quantities of CO2 into a saline formation, CO2CRC Otway Project
A key objective of Stage 2 of the CO2CRC Otway Project is to explore the ability of geophysical methods to detect and monitor injection of greenhouse gas into a saline formation. For this purpose, injection of some 10,000 30,000 tonnes of CO2-rich mixture into the Paaratte formation, a saline aquifer located at a depth of about 1,400 m, is planned. Before such an injection experiment is undertaken, we assess the feasibility of geophysical monitoring using computer modelling. To examine the detectability of the plume we need to estimate the time-lapse signal and time- lapse noise. The time lapse signal is modelled using flow simulations, fluid substitution and seismic forward modelling. In order to assess the applicability of time-lapse seismic to monitor the injection, the predicted signal is compared to the time-lapse noise level from the recent 4D seismic survey acquired at the Otway site in 2009-2010. The methodology is applied to two alternative reservoir intervals located at a depth of 1392-1399 m and 1445-1465 m below the sea level, respectively. These intervals are considered to be the two possible options for the injection. The results show that injection into the lower interval will produce a plume of a larger thickness and smaller lateral extent, and a seismic response that is more likely to be detectable. The developed feasibility assessment workflow, and the results of its application to the Otway site, can be used to assess the ability of seismic methods to detect and monitor greenhouse gas leakage in other CCS projects
The effect of epidural anesthesia on muscle flap tolerance to venous ischemia
Background: Venous ischemia is a major cause of failure after free tissue transfers and replantations. The combination of general and epidural anesthesia leads to vasodilatation and improves tissue perfusion. Postoperative pain relief and sympathetic blockage are additional benefits of epidural anesthesia. The purpose of this study was to determine whether epidural anesthesia has benefits on microcirculation and neutrophil functions in muscle flaps subjected to venous ischemia. METHOD:: Thirty Sprague-Dawley rats were divided into three groups: group I, general anesthesia; group II, spinal anesthesia; and group III, epidural anesthesia. Cremaster flaps were prepared, postcapillary venules were selected under intravital videomicroscopy, and flaps were subjected to venous ischemia. Images were recorded from preselected postcapillary venules before venous ischemia (baseline) and following reperfusion. Neutrophil rolling and adhesion, functional capillary density, and diameters of postcapillary venules were evaluated. Results: The increase in rolling neutrophils in group III was significantly lower than in groups I and II at 60 and 120 minutes. Change of adherent neutrophils in group III was significantly lower than in groups I and II at 15, 60 and 120 minutes. There was significantly more reduction in inner diameter of postcapillary venules in groups I and II compared with group III. Functional capillary density in groups I and II was significantly lower than in group III. Conclusion: Epidural anesthesia regulated neutrophil functions, salvaged functional capillaries, and prevented vasoconstriction of postcapillary venules in cremaster muscle flaps subjected to venous ischemia. Spinal and general anesthesia, however, were found to be ineffective in improving microcirculation of muscle flaps subjected to venous ischemia. © 2009 by the American Society of Plastic Surgeons
Clinical results of carotid artery stenting versus carotid endarterectomy
Objective: To review our results of carotid artery stenting (CAS) and carotid endarterectomy (CEA).
Methods: We evaluated the medical records of patients undergoing carotid artery revascularization procedure, between 2001 and 2013 in Baskent University Hospital, Ankara, Turkey. Carotid artery stenting or CEA procedures were performed in patients with asymptomatic carotid stenosis (=70%) or symptomatic stenosis (=50%). Demographic data, procedural details, and clinical outcomes were recorded. Primary outcome measures were in 30-day stroke/transient ischemic attacks (TIA)/amaurosis fugax or death. Secondary outcome measures were nerve injury, bleeding complications, length of stay in hospital, stroke, restenosis (ICA patency), and all-cause death during long-term follow-up.
Results: One hundred ninety-four CEA and 115 CAS procedures were performed for symptomatic and/or asymptomatic carotid artery stenosis. There is no significant differences 30-day mortality and neurologic morbidity between CAS (13%) and CEA procedures (7.7%). Length of stay in hospital were significantly longer in CEA group (p=0.001). In the post-procedural follow up, only in symptomatic patients, restenosis rate was higher in the CEA group (p=.045). The other endpoints did not differ significantly.
Conclusions: Endovascular stent treatment of carotid artery atherosclerotic disease is an alternative for vascular surgery, especially for patients that are high risk for standard CEA. The increasing experience, development of cerebral protection systems and new treatment protocols increases CAS feasibility
Bioactive peptide functionalized aligned cyclodextrin nanofibers for neurite outgrowth
Guidance of neurite extension and establishment of neural connectivity hold great importance for neural tissue regeneration and neural conduit implants. Although bioactive-epitope functionalized synthetic or natural polymeric materials have been proposed for the induction of neural regeneration, chemical modifications of these materials for neural differentiation still remain a challenge due to the harsh conditions of chemical reactions, along with non-homogeneous surface modifications. In this study, a facile noncovalent functionalization method is proposed by exploiting host-guest interactions between an adamantane-conjugated laminin derived bioactive IKVAV epitope and electrospun cyclodextrin nanofibers (CDNFs) to fabricate implantable scaffolds for peripheral nerve regeneration. While electrospun CDNFs introduce a three-dimensional biocompatible microenvironment to promote cellular viability and adhesion, the bioactive epitopes presented on the surface of electrospun CDNFs guide the cellular differentiation of PC-12 cells. In addition to materials synthesis and smart functionalization, physical alignment of the electrospun nanofibers guides the cells for enhanced differentiation. Cells cultured on aligned and IKVAV functionalized electrospun CDNFs had significantly higher expression of neuron-specific βIII-tubulin and synaptophysin. The neurite extension is also higher on the bioactive aligned scaffolds compared to random and non-functionalized electrospun CDNFs. Both chemical and physical cues were utilized for an effective neuronal differentiation process. © The Royal Society of Chemistry
Noncovalent functionalization of a nanofibrous network with a bio-inspired heavy metal binding peptide
Peptide-polymer nanofibrous networks can be developed to obtain hybrid systems providing both functionalities of peptides and stability and processability of the polymers. In this work, a bio-inspired heavy metal binding peptide was synthesized and noncovalently immobilized on water-insoluble electrospun hydroxypropyl-beta-cyclodextrin nanofibers (CDNF). The peptide functionalized hybrid nanofibers were able to bind to heavy metal ions and facilitated removal of metal ions from water. The peptide-polymer scavenging system has potential for development of further molecular recognition systems with various peptide sequences or host-guest inclusion complexes. © 2013 The Royal Society of Chemistry
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