4,862 research outputs found
Introduction: Sustainable Livelihoods, Conflicts, and Transformation
Introduction to the Journal of Global Initiatives Volume 10, Number 2 Sustainable Livelihoods and Conflict
Shareholder Returns from Supplying Trade Credit
We examine shareholder wealth implications of supplying financing to customers. Robust results demonstrate that excess returns and trade receivables are directly and significantly related. Further evidence indicates the value of receivables is higher for suppliers with stronger motives relating to operating and contracting costs. The results also suggest a discounted value of receivables for financially unconstrained firms. Overall, we conclude that investors recognize trade credit as an effective instrument in mitigating frictions hindering sales growth. Thus, certain suppliers are positioned to derive increased strategic benefits from credit policy
Morphological Classification of Galaxies by Shapelet Decomposition in the Sloan Digital Sky Survey II: Multiwavelength Classification
We describe the application of the `shapelet' linear decomposition of galaxy
images to multi-wavelength morphological classification using the
and -band images of 1519 galaxies from the Sloan Digital Sky Survey. We
utilize elliptical shapelets to remove to first-order the effect of inclination
on morphology. After decomposing the galaxies we perform a principal component
analysis on the shapelet coefficients to reduce the dimensionality of the
spectral morphological parameter space. We give a description of each of the
first ten principal component's contribution to a galaxy's spectral morphology.
We find that galaxies of different broad Hubble type separate cleanly in the
principal component space. We apply a mixture of Gaussians model to the
2-dimensional space spanned by the first two principal components and use the
results as a basis for classification. Using the mixture model, we separate
galaxies into three classes and give a description of each class's physical and
morphological properties. We find that the two dominant mixture model classes
correspond to early and late type galaxies, respectively. The third class has,
on average, a blue, extended core surrounded by a faint red halo, and typically
exhibits some asymmetry. We compare our method to a simple cut on color
and find the shapelet method to be superior in separating galaxies.
Furthermore, we find evidence that the decision boundary may not be
optimal for separation between early and late type galaxies, and suggest that
the optimal cut may be .Comment: 42 pages, 18 figs, revised version in press at AJ. Some modification
to the technique, more discussion, addition/deletion/modification of several
figures, color figures have been added. A high resolution version may be
obtained at
http://bllac.as.arizona.edu/~bkelly/shapelets/shapelets_ugriz.ps.g
Lupus-TR-3b: A Low-Mass Transiting Hot Jupiter in the Galactic Plane?
We present a strong case for a transiting Hot Jupiter planet identified
during a single-field transit survey towards the Lupus Galactic plane. The
object, Lupus-TR-3b, transits a V=17.4 K1V host star every 3.91405d.
Spectroscopy and stellar colors indicate a host star with effective temperature
5000 +/- 150K, with a stellar mass and radius of 0.87 +/- 0.04M_sun and 0.82
+/- 0.05R_sun, respectively. Limb-darkened transit fitting yields a companion
radius of 0.89 +/- 0.07R_J and an orbital inclination of 88.3 +1.3/-0.8 deg.
Magellan 6.5m MIKE radial velocity measurements reveal a 2.4 sigma K=114 +/-
25m/s sinusoidal variation in phase with the transit ephemeris. The resulting
mass is 0.81 +/- 0.18M_J and density 1.4 +/- 0.4g/cm^3. Y-band PANIC image
deconvolution reveal a V>=21 red neighbor 0.4'' away which, although highly
unlikely, we cannot conclusively rule out as a blended binary with current
data. However, blend simulations show that only the most unusual binary system
can reproduce our observations. This object is very likely a planet, detected
from a highly efficient observational strategy. Lupus-TR-3b constitutes the
faintest ground-based detection to date, and one of the lowest mass Hot
Jupiters known.Comment: 4 pages, 4 figures, accepted for publication in ApJ
Predictor of Turnover Intention of Register Nurses: Job Satisfaction or Work Engagement?
Both employee job satisfaction (JS) and employee work engagement (WE) have been examined as possible predictors of employees’ intention to voluntarily leave a specific job or company, known as turnover intention (TI). While the body of knowledge has grown concerning the nature of TI, there remains the unsettled question of which of the two concepts most accurately predicates TI. The high turnover rate of registered nurses (RNs) in hospitals in the U.S. presented an opportunity to examine if JS and WE predict, and to what degree, among RNs. For this quantitative correlational research probability sampling was used to identify 155 participants, all full-time registered nurses with 2 or more years of employment in New York hospitals. Data, obtained from surveys, were analyzed via multiple linear regression. The results revealed that only job satisfaction predicted turnover intention among the nurses sampled, F (5,154) = 12.008, p R2 = 287.The findings indicate that leaders of healthcare organizations, might lower nurse turnover intention by focusing on improving job satisfaction. Specifically, TI may be lower by addressing the issues identified from regular job satisfaction surveys, and by a greater emphasis on creating a more satisfying workplace. A more stable RN workforce could reduce healthcare disruptions in communities
Nitrosative stress induces DNA strand breaks but not caspase mediated apoptosis in a lung cancer cell line
BACKGROUND: Key steps crucial to the process of tumor progression are genomic instability and escape from apoptosis. Nitric oxide and its interrelated reactive intermediates (collectively denoted as NO(X)) have been implicated in DNA damage and mutational events leading to cancer development, while also being implicated in the inhibition of apoptosis through S-nitrosation of key apoptotic enzymes. The purpose of this study was to explore the interrelationship between NO(X)-mediated DNA strand breaks (DSBs) and apoptosis in cultured tumor cell lines. METHODS: Two well-characterized cell lines were exposed to increasing concentrations of exogenous NO(X )via donor compounds. Production of NO(X )was quantified by the Greiss reaction and spectrophotometery, and confirmed by nitrotyrosine immunostaining. DSBs were measured by the alkaline single-cell gel electrophoresis assay (the COMET assay), and correlated with cell viability by the MTT assay. Apoptosis was analyzed both by TUNEL staining and Annexin V/propidium iodine FACS. Finally, caspase enzymatic activity was measured using an in-vitro fluorogenic caspase assay. RESULTS: Increases in DNA strand breaks in our tumor cells, but not in control fibroblasts, correlated with the concentration as well as rate of release of exogenously administered NO(X). This increase in DSBs did not correlate with an increase in cell death or apoptosis in our tumor cell line. Finally, this lack of apoptosis was found to correlate with inhibition of caspase activity upon exposure to thiol- but not NONOate-based NO(X )donor compounds. CONCLUSIONS: Genotoxicity appears to be highly interrelated with both the concentration and kinetic delivery of NO(X). Moreover, alterations in cell apoptosis can be seen as a consequence of the explicit mechanisms of NO(X )delivery. These findings lend credence to the hypothesis that NO(X )may play an important role in tumor progression, and underscores potential pitfalls which should be considered when developing NO(X)-based chemotherapeutic agents
Comparison of a Continuous and Discontinuous GXT on VO2 in Resistance-Trained and Endurance-Trained Males
International Journal of Exercise Science 15(4): 414-422, 2022. Traditional graded exercise testing to assess maximal oxygen uptake (VO2max) may not well represent resistance-trained athletes due to their unfamiliarity with continuous exercise. For this reason, it is possible discontinuous exercise protocols may better represent the maximum capacity for aerobic metabolism in resistance-trained athletes, in order to provide a more valid assessment of VO2max and risk of developing cardiovascular disease. Purpose: The purpose of this experiment was to compare VO2peak during a continuous and discontinuous modified Bruce protocol in both highly resistance-trained and endurance-trained males. Methods: 19 college-aged males (age: 20.6 ± 1.9 yr, height: 176.5 ± 7.6 cm, weight: 85.0 ± 25.6 kg) of intermediate resistance- or endurance-trained status were recruited for this study. Participants completed a continuous and discontinuous modified Bruce protocol on two visits separated by seven days. Results: A 2x2 one-way ANOVA revealed a significant group main effect for VO2peak (p = 0.004) in which endurance athletes achieved significantly higher VO2peak values compared to resistance-trained athletes. A significant group main effect for RPE was found (p = 0.045) in which endurance-trained reported significantly higher RPE values than the resistance-trained. A significant main effect for protocol for heart rate (p = 0.033) was found in which individuals achieved higher heart rates during the continuous protocol compared to the discontinuous. Conclusion: Although a discontinuous protocol with rest periods between stages is comparable to the exercise mode familiar to resistance-trained athletes, it did not provide any additional benefit to VO2peak values
Analyzing Feshbach resonances -- A Li -Cs case study
We provide a comprehensive comparison of a coupled channels calculation, the
asymptotic bound state model (ABM), and the multichannel quantum defect theory
(MQDT). Quantitative results for Li -Cs are presented and compared
to previously measured Li -Cs Feshbach resonances (FRs) [M. Repp et
al., Phys. Rev. A 87 010701(R) (2013)]. We demonstrate how the accuracy of the
ABM can be stepwise improved by including magnetic dipole-dipole interactions
and coupling to a non-dominant virtual state. We present a MQDT calculation,
where magnetic dipole-dipole and second order spin-orbit interactions are
included. A frame transformation formalism is introduced, which allows the
assignment of measured FRs with only three parameters. All three models achieve
a total rms error of < 1G on the observed FRs. We critically compare the
different models in view of the accuracy for the description of FRs and the
required input parameters for the calculations.Comment: 16 pages, 3 figures, 1 tabl
Mathematics of Floating 3D Printed Objects
We explore the stability of floating objects through mathematical modeling
and experimentation. Our models are based on standard ideas of center of
gravity, center of buoyancy, and Archimedes' Principle. We investigate a
variety of floating shapes with two-dimensional cross sections and identify
analytically and/or computationally a potential energy landscape that helps
identify stable and unstable floating orientations. We compare our analyses and
computations to experiments on floating objects designed and created through 3D
printing. In addition to our results, we provide code for testing the floating
configurations for new shapes, as well as giving details of the methods for 3D
printing the objects. The paper includes conjectures and open problems for
further study.Comment: 30 pages, 16 figure
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