618 research outputs found
The Determinants of Music Piracy in a Sample of College Students
Why do some individuals pirate digital music while others pay for it? Using data on a sample of undergraduate students, we study the determinants of music piracy by looking at whether a respondent’s last song was obtained illegally or not. In doing so, we incorporate (i) the individual-specific transactions costs that constitute the effective price of illegal music; and (ii) individual willingness to pay (WTP) for digital music, which we elicit using a simple field experiment and which we use to control for the unobserved heterogeneity of preferences between respondents. Our empirical results indicate that a respondent’s subjective probability of facing a lawsuit and her degree of morality both have a negative impact on the likelihood that her last song was obtained illegally. These results are robust whether WTP is estimated parametrically or nonparametrically. We conclude by discussing the practical implications of our findings.Music Piracy, Transactions Costs, Subjective Expectations
Myopic Loss Aversion: Information Feedback vs. Investment Flexibility
We experimentally disentangle the effect of information feedback from the effect of investment flexibility on the investment behavior of a myopically loss averse investor.Our findings show that varying the information condition alone suffices to induce behavior that is in line with the hypothesis of Myopic Loss Aversion.information;investment
Household-Level Livestock Marketing Behavior Among Northern Kenyan and Southern Ethiopian Pastoralists
Pastoralists in East Africa's arid and semi-arid lands (ASAL) regularly confront climatic shocks triggering massive herd die-offs and loss of scarce wealth. On the surface, it appears puzzling that pastoralists do not make extensive use of livestock markets to offload animals when climatic shocks temporarily reduce the carrying capacity of local rangelands, and then use markets to restock their herds when local conditions recover. In recent years, donors and policy makers have begun to hypothesize that investments in livestock marketing systems might quickly pay for themselves through reduced demand for relief aid,by increasing pastoralist marketing responsiveness to temporal variation in range conditions.Marketing,
Reversibility of airflow obstruction by hypoglossus nerve stimulation in anesthetized rabbits
Rationale: Anesthesia-induced uncoupling of upper airway dilating and inspiratory pump muscles activation may cause inspiratory flow limitation, thereby mimicking obstructive sleep apnea/hypopnea. Objectives: Determine whether inspiratory flow limitation occurs in spontaneously breathing anesthetized rabbits and whether this can be reversed by direct hypoglossal nerve stimulation and by the application of continuous positive airway pressure. Methods: Ten New Zealand White rabbits were anesthetized, instrumented, and studied supine while breathing spontaneously at ambient pressure or during the application of positive or negative airway pressure. Under each of these conditions, the effect of unilateral or bilateral hypoglossal nerve stimulation was investigated. Measurements: Inspiratory flow and tidal volume were measured together with esophageal pressure and the electromyographic activity of diaphragm, alae nasi, and genioglossus muscles. Main results: Anesthesia caused a marked increase in inspiratory resistance, snoring, and in eight rabbits, inspiratory flow limitation. Hypoglossus nerve stimulation was as effective as continuous positive airway pressure in reversing inspiratory flow limitation and snoring. Its effectiveness increased progressively as airway opening pressure was lowered, reached a maximum at -5 cm H2O, but declined markedly at lower pressures. With negative airway opening pressure, airway collapse eventually occurred during inspiration that could be prevented by hypoglossus nerve stimulation. The recruitment characteristics of hypoglossus nerve fibers was steep, and significant upper airway dilating effects already obtained with stimulus intensities 36 to 60% of maximum. Conclusion: This study supports hypoglossus nerve stimulation as a treatment option for obstructive sleep apnea
Etude des résultats d'exploitation d'unités de pêche artisanale en Martinique
L'étude des résultats d'exploitations de 55 unités de pêche, durant la période de Miquelon (de Décembre à Juin 1986) fait apparaître des résultats économiques certes variables mais, dans l'ensemble, médiocres : sur les 1397 sorties observées, près de la moitié aboutit à un niveau de recette nette de coûts variables négative et un peu plus du quart de ces sorties dégage une recette nette de C.V. compris entre 0 et 499 francs. Sur les 55 unités de pêche étudiées, plus du tiers des patrons de pêcheurs ont un résultat négatif et près de 50 % ont "une part patron" mensualisée inférieure au SMIC (Résumé d'auteur
Structural and antimicrobial properties of human pre-elafin/trappin-2 and derived peptides against Pseudomonas aeruginosa
<p>Abstract</p> <p>Background</p> <p>Pre-elafin/trappin-2 is a human innate defense molecule initially described as a potent inhibitor of neutrophil elastase. The full-length protein as well as the N-terminal "cementoin" and C-terminal "elafin" domains were also shown to possess broad antimicrobial activity, namely against the opportunistic pathogen <it>P. aeruginosa</it>. The mode of action of these peptides has, however, yet to be fully elucidated. Both domains of pre-elafin/trappin-2 are polycationic, but only the structure of the elafin domain is currently known. The aim of the present study was to determine the secondary structures of the cementoin domain and to characterize the antibacterial properties of these peptides against <it>P. aeruginosa</it>.</p> <p>Results</p> <p>We show here that the cementoin domain adopts an α-helical conformation both by circular dichroism and nuclear magnetic resonance analyses in the presence of membrane mimetics, a characteristic shared with a large number of linear polycationic antimicrobial peptides. However, pre-elafin/trappin-2 and its domains display only weak lytic properties, as assessed by scanning electron micrography, outer and inner membrane depolarization studies with <it>P. aeruginosa </it>and leakage of liposome-entrapped calcein. Confocal microscopy of fluorescein-labeled pre-elafin/trappin-2 suggests that this protein possesses the ability to translocate across membranes. This correlates with the finding that pre-elafin/trappin-2 and elafin bind to DNA <it>in vitro </it>and attenuate the expression of some <it>P. aeruginosa </it>virulence factors, namely the biofilm formation and the secretion of pyoverdine.</p> <p>Conclusions</p> <p>The N-terminal cementoin domain adopts α-helical secondary structures in a membrane mimetic environment, which is common in antimicrobial peptides. However, unlike numerous linear polycationic antimicrobial peptides, membrane disruption does not appear to be the main function of either cementoin, elafin or full-length pre-elafin/trappin-2 against <it>P. aeruginosa</it>. Our results rather suggest that pre-elafin/trappin-2 and elafin, but not cementoin, possess the ability to modulate the expression of some <it>P.aeruginosa </it>virulence factors, possibly through acting on intracellular targets.</p
Effects of conventional and closed-loop neurally adjusted ventilatory assist in intubated spinal cord injured patients
- …