3,098 research outputs found
The opsonizing ligand on Salmonella typhimurium influences incorporation of specific, but not azurophil, granule constituents into neutrophil phagosomes.
Phagosomes were purified from human neutrophils ingesting Salmonella typhimurium opsonized with adsorbed normal human serum or with rabbit IgG. Constituents within the phagosome were endogenously labeled by supplying the cells with 125INa during phagocytosis. Lactoferrin and vitamin B12 binding protein (TC1 and TC3), markers for specific granules, were present in the phagosomes from neutrophils ingesting S. typhimurium opsonized with IgG but were 3.5- to 5-fold less prominent in phagosomes from cells phagocytosing Salmonella bearing C3 fragments only. In contrast, iodinated azurophilic granule components, most prominently defensins, were the major constituents in phagosomes prepared under both opsonization conditions. Furthermore, labeled complement (CR1 and CR3) and immunoglobulin (Fc gamma RIII) receptors were incorporated in the phagosome regardless of the ligand mediating phagocytosis. These results suggest that the ligand-receptor interactions mediating phagocytosis influence incorporation of neutrophil-specific granule contents into phagosomes
Civic Associations That Work: The Contributions of Leadership to Organizational Effectiveness
Why are some civic associations more effective at advancing their public agendas, engaging members, and developing leaders? We introduce a multi-dimensional framework for analyzing the comparative effectiveness of member-based civic associations in terms of public influence, member engagement, and leader development. Theoretical expectations in organization studies, sociology, political science, and industrial relations hold that organizations benefiting from either a favorable environment or abundant resources will be most effective. Using systematic data on the Sierra Clubs 400 local organizations, we assess these factors alongside an alternative approach focusing on the role of leaders, how they work together, and the activities they carry out to build capacity and conduct programs. While we find modest support for the importance of an organizations available resources and external environment, we find strong evidence for each of our three outcomes supporting our claim that effectiveness in civic associations depends to a large degree on internal organizational practices.This publication is Hauser Center Working Paper No. 36. The Hauser Center Working Paper Series was launched during the summer of 2000. The Series enables the Hauser Center to share with a broad audience important works-in-progress written by Hauser Center scholars and researchers
The adiabatic evolution of orbital parameters in the Kerr spacetime
We investigate the adiabatic orbital evolution of a point particle in the
Kerr spacetime due to the emission of gravitational waves. In the case that the
timescale of the orbital evolution is enough smaller than the typical timescale
of orbits, the evolution of orbits is characterized by the change rates of
three constants of motion, the energy , the azimuthal angular momentum ,
and the Carter constant . For and , we can evaluate their change
rates from the fluxes of the energy and the angular momentum at infinity and on
the event horizon according to the balance argument. On the other hand, for the
Carter constant, we cannot use the balance argument because we do not know the
conserved current associated with it. %and the corresponding conservation law.
Recently, Mino proposed a new method of evaluating the averaged change rate of
the Carter constant by using the radiative field. In our previous paper we
developed a simplified scheme for practical evaluation of the evolution of the
Carter constant based on the Mino's proposal. In this paper we describe our
scheme in more detail, and derive explicit analytic formulae for the change
rates of the energy, the angular momentum and the Carter constant.Comment: 34 pages, no figur
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Reducing the rare event: lessons from the implementation of a ventilator bundle.
The ventilator-associated event (VAE) is a potentially avoidable complication of mechanical ventilation (MV) associated with poor outcomes. Although rare, VAEs and other nosocomial events are frequently targeted for quality improvement efforts consistent with the creed to 'do no harm'. In October 2016, VA Greater Los Angeles (GLA) was in the lowest-performing decile of VA medical centres on a composite measure of quality, owing to GLA's relatively high VAE rate. To decrease VAEs, we sought to reduce average MV duration of patients with acute respiratory failure to less than 3 days by 1 July 2017. In our first intervention (period 1), intensive care unit (ICU) attending physicians trained residents to use an existing ventilator bundle order set; in our second intervention (period 2), we updated the order set to streamline order entry and incorporate new nurse-driven and respiratory therapist (RT)-driven spontaneous awakening trial (SAT) and spontaneous breathing trial (SBT) protocols. In period 1, the proportion of eligible patients with SAT and SBT orders increased from 29.9% and 51.2% to 67.4% and 72.6%, respectively, with sustained improvements through December 2017. Mean MV duration decreased from 7.2 days at baseline to 5.5 days in period 1 and 4.7 days in period 2; statistical process control charts revealed no significant differences, but the difference between baseline and period 2 MV duration was statistically significant at p=0.049. Bedside audits showed RTs consistently performed indicated SBTs, but there were missed opportunities for SATs due to ICU staff concerns about the SAT protocol. The rarity of VAEs, small population of ventilated patients and infrequent use of sedative infusions at GLA may have decreased the opportunity to achieve staff acceptance and use of the SAT protocol. Quality improvement teams should consider frequency of targeted outcomes when planning interventions; rare events pose challenges in implementation and evaluation of change
Analytic models of ducted turbomachinery tone noise sources. Volume 1: Analysis
The analytic models developed for computing the periodic sound pressure of subsonic fans and compressors in an infinite, hardwall annular duct with uniform flow are described. The basic sound-generating mechanism is the scattering into sound waves of velocity disturbances appearing to the rotor or stator blades as a series of harmonic gusts. The models include component interactions and rotor alone
Analytic models of ducted turbomachinery tone noise sources. Volume 3: Program test case results
Computer programs for analyzing the acoustic properties of turbomachinery with ducted flow were developed. The models include component interactions and rotor alone. Test case results determined from the computer programs are presented
Analytic models of ducted turbomachinery tone noise sources. Volume 2: Subprogram documentation
Analytical models were developed for computing the periodic sound pressures of subsonic fans in an infinite hardwall annular duct with uniform flow. The computer programs are described which are used for numerical computations of sound pressure mode amplitudes. The data are applied to the acoustic properties of turbomachinery
Antecedents of service innovation in manufacturing SMEs: an empirical research
Services have become an increasingly important competitive lever for manufacturing firms. Service innovation, therefore, emerges as a critical capability also for manufacturing companies. An empirical research was carried out in business-to-business markets, based on the “InnoScore© Service” methodology, developed at the Fraunhofer IAO. Through the analysis of collected data, the paper aims at understanding the role of an-tecedents of service innovation, such as the company strategy and the ex-istence of a service oriented culture. These factors should support the def-inition of processes, tools and organizational practices for service innovation and end up in improved business results. The evidence ob-tained through the data analysis, described and discussed in the paper, support these claims
New Results from NA49
We present recent results of the SPS experiment NA49 on production of strange
particles and event-by-event fluctuations of mean and of charged particle
ratios in central Pb+Pb collisions at various beam energies (40, 80, 158 AGeV)
as well as in different collisions at 158 AGeV, going from p+p over light-ion
collisions to peripheral and central Pb+Pb.Comment: 5 pages, 6 figures (in eps) talk given at XXXI International
Symposium on Multiparticle Dynamics, Sep. 1-7, 2001, Datong China URL
http://ismd31.ccnu.edu.cn
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The Relationship of Leadership Quality to the Political Presence of Civic Associations
Member-based civic associations, or citizen groups, have two crucial roles in American democracy. They advocate for members' interests in the public arena, but also operate as Tocquevillian “schools of democracy” linking citizens to politics and equipping them with the skills of democratic citizenship. Yet scant research has examined the interrelationships of these two roles. Does the work that civic associations do in developing democratic participants enhance the work they do advocating for members' interests in the public arena? We bring together two previously disparate strands of research on civic associations by arguing that a key factor affecting the political presence of civic associations is leadership quality. We focus on the relationship of leadership quality to political presence, using data from a unique 2003 study of 226 local entities of the Sierra Club. We show that organizations with more skilled and committed leaders have higher levels of political presence. This contrasts with previous research that has focused primarily on community context and resources as explanatory factors. This study shows that political presence is related to the extent to which leaders develop their skills and demonstrate commitment to the organization
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