1,284 research outputs found
The Tully-Fisher relation of COLD GASS Galaxies
We present the stellar mass (M*) and Wide-Field Infrared Survey Explorer absolute Band 1 magnitude (MW1) Tully–Fisher relations (TFRs) of subsets of galaxies from the CO Legacy Database for the GALEX Arecibo SDSS Survey (COLD GASS). We examine the benefits and drawbacks of several commonly used fitting functions in the context of measuring CO(1–0) linewidths (and thus rotation velocities), favouring the Gaussian Double Peak function. We find the MW1 and M* TFR, for a carefully selected sub-sample, to be MW1=(−7.1±0.6)[log(W50/sinikms−1)−2.58]−23.83±0.09MW1=(−7.1±0.6)[log(W50/sinikms−1)−2.58]−23.83±0.09 and log(M∗/M⊙)=(3.3±0.3)[log(W50/sinikms−1)−2.58]+10.51±0.04log(M∗/M⊙)=(3.3±0.3)[log(W50/sinikms−1)−2.58]+10.51±0.04, respectively, where W50 is the width of a galaxy's CO(1–0) integrated profile at 50 per cent of its maximum and the inclination i is derived from the galaxy axial ratio measured on the Sloan Digitized Sky Survey r-band image. We find no evidence for any significant offset between the TFRs of COLD GASS galaxies and those of comparison samples of similar redshifts and morphologies. The slope of the COLD GASS M* TFR agrees with the relation of Pizagno et al. However, we measure a comparatively shallower slope for the COLD GASS MW1 TFR as compared to the relation of Tully & Pierce. We attribute this to the fact that the COLD GASS sample comprises galaxies of various (late-type) morphologies. Nevertheless, our work provides a robust reference point with which to compare future CO TFR studies
Evaluation of Cathode Gas Composition and Temperature Influences on Alkaline Anion Exchange Membrane Fuel Cell (AAEMFC) Performance
The effects of different temperatures (55, 65, 75 and 85 °C) and cathode gas compositions (O2, synthetic air, air and 90% synthetic air+10% CO2) on alkaline anion exchange membrane fuel cell (AAEMFC) were evaluated. Membrane electrode assemblies (MEA) were fabricated using commercial anion exchange membrane (AEM) in OH- form and Pt catalyst. Polarization curves and voltage responses during constant current were performed in order to describe the influences of temperature and gas composition on the AAEMFC performance. The experimental results showed that the fuel cell performance increases with elevating temperatures for all applied gas compositions. Highest power density of 34.7 mW cm-2 was achieved for pure O2 as cathode feed. A decrease to 20.3 mW cm-2 was observed when cathode gas composition was changed to synthetic air due to reduction of the O2 partial pressure. The presence of CO2 in atmospheric air applied to the cathode stream caused a further drop of the maximum power density to 15.2 mW cm-2 driven by neutralization of OH- ions with CO2
Recommended from our members
A novel rapid-onset high-penetrance plasmacytoma mouse model driven by deregulation of cMYC cooperating with KRAS12V in BALB/c mice
Our goal is to develop a rapid and scalable system for functionally evaluating deregulated genes in multiple myeloma (MM). Here, we forcibly expressed human cMYC and KRAS12V in mouse T2 B cells (IgM+B220+CD38+IgD+) using retroviral transduction and transplanted these cells into lethally irradiated recipient mice. Recipients developed plasmacytomas with short onset (70 days) and high penetrance, whereas neither cMYC nor KRAS12V alone induced disease in recipient mice. Tumor cell morphology and cell surface biomarkers (CD138+B220−IgM−GFP+) indicate a plasma cell neoplasm. Gene set enrichment analysis further confirms that the tumor cells have a plasma cell gene expression signature. Plasmacytoma cells infiltrated multiple loci in the bone marrow, spleen and liver; secreted immunoglobulins; and caused glomerular damage. Our findings therefore demonstrate that deregulated expression of cMYC with KRAS12V in T2 B cells rapidly generates a plasma cell disease in mice, suggesting utility of this model both to elucidate molecular pathogenesis and to validate novel targeted therapies
The PDGFRα-laminin B1-keratin 19 cascade drives tumor progression at the invasive front of human hepatocellular carcinoma
Human hepatocellular carcinomas (HCCs) expressing the biliary/hepatic progenitor cell marker keratin 19 (K19) have been linked with a poor prognosis and exhibit an increase in platelet-derived growth factor receptor a (PDGFR alpha) and laminin beta 1 (LAMB1) expression. PDGFR alpha has been reported to induce de novo synthesis of LAMB1 protein in a Sjogren syndrome antigen B (La/SSB)-dependent manner in a murine metastasis model. However, the role of this cascade in human HCC remains unclear. This study focused on the functional role of the PDGFR alpha-La/SSB-LAMB1 pathway and its molecular link to K19 expression in human HCC. In surgical HCC specimens from a cohort of 136 patients, PDGFR alpha expression correlated with K19 expression, microvascular invasion and metastatic spread. In addition, PDGFR alpha expression in pre-operative needle biopsy specimens predicted poor overall survival during a 5-year follow-up period. Consecutive histological staining demonstrated that the signaling components of the PDGFR alpha-La/SSB-LAMB1 pathway were strongly expressed at the invasive front. K19-positive HCC cells displayed high levels of alpha 2 beta 1 integrin (ITG) receptor, both in vitro and in vivo. In vitro activation of PDGFR alpha signaling triggered the translocation of nuclear La/SSB into the cytoplasm, enhanced the protein synthesis of LAMB1 by activating its internal ribosome entry site, which in turn led to increased secretion of laminin-111. This effect was abrogated by the PDGFR alpha-specific inhibitor crenolanib. Importantly LAMB1 stimulated ITG-dependent focal adhesion kinase/Src proto-oncogene non-receptor tyrosine kinase signaling. It also promoted the ITG-specific downstream target Rho-associated coiled-coil containing protein kinase 2, induced K19 expression in an autocrine manner, invadopodia formation and cell invasion. Finally, we showed that the knockdown of LAMB1 or K19 in subcutaneous xenograft mouse models resulted in significant loss of cells invading the surrounding stromal tissue and reduced HepG2 colonization into lung and liver after tail vein injection. The PDGFR alpha-LAMB1 pathway supports tumor progression at the invasive front of human HCC through K19 expression
Monitoring the changes of Lake Uluabat Ramsar site and its surroundings in the 1985-2021 period using RS and GIS methods
Ramsar sites are important ecosystems that are protected by international status, have great value in terms of biodiversity, and constitute a resource in terms of economic, cultural, scientific and recreational aspects. In this study, the change of Lake Uluabat Ramsar Site and its surroundings, between the years 1985-2021 has been observed. For this, Remote Sensing (RS) and Geographic Information Systems (GIS) methods were used. Vegetation change in the lake and its surroundings in 1985, 2000, 2015 and 2021 with Normalized Difference Vegetation Index (NDVI), and changes in water surfaces with the water indices Normalized Difference Water Index (NDWI) and Modified Normalized Difference Water Index (mNDWI) were analyzed by using Landsat multi-band satellite images (Landsat 5 TM, Landsat 7 ETM and Landsat 8 OLI/TIRS) as RS data. The resulting changes were monitored and the success of the indices in determining these areas and the relations of the indices with each other were questioned by Accuracy index, Kappa coefficent, and Correlation analyses. The results show 36-year long-term changes and reveal a 13.06% shrinkage of Uluabat Lake wetland and surrounding water areas with the highest kappa coefficients for mNDWI as 0.83, 0.90, 0.93, 0.97, respectively, over the years studied
Determination of ontogenetic selection criteria for grain yield in spring barley (Hordeum vulgare) by pathcoefficient analysis
Path-coefficient analysis was performed to determine the interrelationships among grain yield, yield components (spike number per m-2, kernel number per spike, average kernel weight) and somephenological characteristics (duration and growing degree-days of vegetative and grain-filling periods) in spring barley genotypes in 2004-2005. Grain yield depended mainly on spike number per m-2 andkernel number per spike; average kernel weight had a negligible effect on grain yield in spring barley genotypes. Grain yield was significantly and positively associated with the spike number per m-2 andnegatively correlated with other characteristics studied. Spike number per m-2 had considerable negative effect on the average kernel weight. A lengthening of the grain-filling period induced an increase in the average kernel weight and a positive and significant correlation was found between the two characteristics. Spike number per m-2 and kernel number had positive direct effects on grain yield in spring barley genotypes. The growing degree-days (GDD) for vegetative period had significant positive direct effect on kernel number, and the GDD for grain-filling period had significant positive direct effect on kernel weight. The results indicated that spike number per m-2, kernel number per spike and the GDD for vegetative and grain filling period were the most reliable selection criteria for improving grain yield in spring barley in cool and short-season environments
Integrated short and medium term underground mine production scheduling
The development of short- and medium-term mine production schedules in isolation from each other has meant that only a local optimum can be achieved when each scheduling phase is carried out. The globally optimal solution, however, can be achieved when integrating scheduling phases and accounting for the interaction between short-term and medium-term activities simultaneously. This paper addresses the task of integrating short- and medium term production plans by combining the short-term objective of minimizing deviation from targeted mill feed grade with the medium-term objective of maximizing net present value (NPV) into a single mathematical optimization model. A conceptual sublevel stoping operation comprising 30 stopes is used for trialling segregated and integrated scheduling approaches. Segregated medium- and short-term scheduling using separate models achieved an NPV of 42 823 657 with smoother mill feed grade. The larger the stope data set, the larger the difference between the two scheduling approaches is likely to be. At the very least, an integrated approach ensures feasibility across the two scheduling horizons, which cannot always be assumed when using a segregated approach
Familiarity bias and physiological responses in contagious yawning by dogs support link to empathy
In humans, the susceptibility to yawn contagion has been theoretically and empirically related to our capacity for empathy. Because of its relevance to evolutionary biology, this phenomenon has been the focus of recent investigations in nonhuman species. In line with the empathic hypothesis, contagious yawning has been shown to correlate with the level of social attachment in several primate species. Domestic dogs (Canis familiaris) have also shown the ability to yawn contagiously. To date, however, the social modulation of dog contagious yawning has received contradictory support and alternative explanations (i.e., yawn as a mild distress response) could explain positive evidence. The present study aims to replicate contagious yawning in dogs and to discriminate between the two possible mediating mechanisms (i.e., empathic vs. distress related response). Twenty-five dogs observed familiar (dog’s owner) and unfamiliar human models (experimenter) acting out a yawn or control mouth movements. Concurrent physiological measures (heart rate) were additionally monitored for twenty-one of the subjects. The occurrence of yawn contagion was significantly higher during the yawning condition than during the control mouth movements. Furthermore, the dogs yawned more frequently when watching the familiar model than the unfamiliar one demonstrating that the contagiousness of yawning in dogs correlated with the level of emotional proximity. Moreover, subjects’ heart rate did not differ among conditions suggesting that the phenomenon of contagious yawning in dogs is unrelated to stressful events. Our findings are consistent with the view that contagious yawning is modulated by affective components of the behavior and may indicate that rudimentary forms of empathy could be present in domesticated dogs
International consensus on (ICON) anaphylaxis
ICON: Anaphylaxis provides a unique perspective on the principal evidence-based anaphylaxis guidelines developed and published independently from 2010 through 2014 by four allergy/immunology organizations. These guidelines concur with regard to the clinical features that indicate a likely diagnosis of anaphylaxis -- a life-threatening generalized or systemic allergic or hypersensitivity reaction. They also concur about prompt initial treatment with intramuscular injection of epinephrine (adrenaline) in the mid-outer thigh, positioning the patient supine (semi-reclining if dyspneic or vomiting), calling for help, and when indicated, providing supplemental oxygen, intravenous fluid resuscitation and cardiopulmonary resuscitation, along with concomitant monitoring of vital signs and oxygenation. Additionally, they concur that H1-antihistamines, H2-antihistamines, and glucocorticoids are not initial medications of choice. For self-management of patients at risk of anaphylaxis in community settings, they recommend carrying epinephrine auto-injectors and personalized emergency action plans, as well as follow-up with a physician (ideally an allergy/immunology specialist) to help prevent anaphylaxis recurrences. ICON: Anaphylaxis describes unmet needs in anaphylaxis, noting that although epinephrine in 1 mg/mL ampules is available worldwide, other essentials, including supplemental oxygen, intravenous fluid resuscitation, and epinephrine auto-injectors are not universally available. ICON: Anaphylaxis proposes a comprehensive international research agenda that calls for additional prospective studies of anaphylaxis epidemiology, patient risk factors and co-factors, triggers, clinical criteria for diagnosis, randomized controlled trials of therapeutic interventions, and measures to prevent anaphylaxis recurrences. It also calls for facilitation of global collaborations in anaphylaxis research. In addition to confirming the alignment of major anaphylaxis guidelines, ICON: Anaphylaxis adds value by including summary tables and citing 130 key references. It is published as an information resource about anaphylaxis for worldwide use by healthcare professionals, academics, policy-makers, patients, caregivers, and the public
- …
