2,782,730 research outputs found

    The impact of antibiotic use on transmission of resistant bacteria in hospitals: Insights from an agent-based model

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    Extensive antibiotic use over the years has led to the emergence and spread of antibiotic resistant bacteria (ARB). Antibiotic resistance poses a major threat to public health since for many infections antibiotic treatment is no longer effective. Hospitals are focal points for ARB spread. Antibiotic use in hospitals exerts selective pressure, accelerating the spread of ARB. We used an agent-based model to explore the impact of antibiotics on the transmission dynamics and to examine the potential of stewardship interventions in limiting ARB spread in a hospital. Agents in the model consist of patients and health care workers (HCW). The transmission of ARB occurs through contacts between patients and HCW and between adjacent patients. In the model, antibiotic use affects the risk of transmission by increasing the vulnerability of susceptible patients and the contagiousness of colonized patients who are treated with antibiotics. The model shows that increasing the proportion of patients receiving antibiotics increases the rate of acquisition non-linearly. The effect of antibiotics on the spread of resistance depends on characteristics of the antibiotic agent and the density of antibiotic use. Antibiotic's impact on the spread increases when the bacterial strain is more transmissible, and decreases as resistance prevalence rises. The individual risk for acquiring ARB increases in parallel with antibiotic density both for patients treated and not treated with antibiotics. Antibiotic treatment in the hospital setting plays an important role in determining the spread of resistance. Interventions to limit antibiotic use have the potential to reduce the spread of resistance, mainly by choosing an agent with a favorable profile in terms of its impact on patient's vulnerability and contagiousness. Methods to measure these impacts of antibiotics should be developed, standardized, and incorporated into drug development programs and approval packages

    Phenomenology and/or objects of exchange

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    This paper begins with explaining my diagram titled 'An interpretation of how Phenomenology and DNA meet in the cultural prosthetic in Bernard Stiegler’s ‘Technics and Time’'. It continues through anecdotally recalling an experience I had as a tutor with an art student and then develops two positions concerning the ontology of artworks that are stimulated by Mario Perniola's 'Art and its Shadow' (2004). These positions are then extrapolated into the dynamic of arts education and the proposition of a methodology peculiar to art. A methodology that attempts to negotiate the valorisation of artworks as artifacts and the valorisation of artworks as social processes of mediation. This duality is resolved in the question of the incorporation of the inorganic artefact, a process that produces viscosity in the inorganic and retards social processes

    A review of the genus Agapetus Curtis (Trichoptera: Glossosomatidae) in eastern and central North America, with description of 12 new species

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    Twenty-nine species of caddisflies in the genus Agapetus Curtis in eastern and central North America are reviewed. Twelve are described as new species: Agapetus aphallus (known only from females); Agapetus baueri, Agapetus flinti, Agapetus harrisi, Agapetus hesperus, Agapetus ibis, Agapetus kirchneri, Agapetus meridionalis, Agapetus pegram, Agapetus ruiteri, Agapetus stylifer, and Agapetus tricornutus. Agapetus rossi Denning 1941 is recognized as a junior subjective synonym of Agapetus walkeri (Betten and Mosely 1940), new synonym. A key to males is provided, and species’ distributions are mapped

    Dual drive actuators

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    A new class of electromechanical actuators is described. These dual drive actuators were developed for the NASA-JPL Galileo Spacecraft. The dual drive actuators are fully redundant and therefore have high inherent reliability. They can be used for a variety of tasks, and they can be fabricated quickly and economically

    Mechanical sequencer

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    A mechanical sequencer having a rotatable drive shaft is described. The drive shaft has a spline formed thereon. A freely rotatable shaft contains a plurality of rollers positioned thereon, the axis of the freely rotatable shaft having an axis parallel to and offset from the axis of the drive shaft. A drive fitting has an opening therein, the drive fitting being positioned on the drive shaft spline for rotating the fitting with the shaft. A finger is formed integral with the drive fitting for enabling the fitting to move the rollers and the freely rotatable shift. A crank structure is positioned in a plane in a plane perpendicular to the axis of the drive shaft and the freely rotatable shaft. The crank structure has a drive shaft opening through which the shaft passes. The crank structure further contains a slot into which the freely rotatable shaft and one of the rollers extends for driving the crank structure during movement of the freely rotatable shaft

    Bidirectional drive and brake mechanism

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    A space transport vehicle is disclosed as including a body which is arranged to be movably mounted on an elongated guide member disposed in outer space and driven therealong. A drive wheel is mounted on a drive shaft and arranged to be positioned in rolling engagement with the elongated guide carrying the vehicle. A brake member is arranged on the drive shaft for movement into and out of engagement with an adjacent surface of the drive wheel. An actuator is mounted on the body to be manually moved back and forth between spaced positions in an arc of movement. A ratchet-and-pawl mechanism is arranged to operate upon movements of the actuator in one direction between first and second positions for coupling the actuator to the drive wheel to incrementally rotate the wheel in one rotational direction and to operate upon movements of the actuator in the opposite direction for uncoupling the actuator from the wheel. The brake member is threadedly coupled to the drive shaft in order that the brake member will be operated only when the actuator is moved on beyond its first and second positions for shifting the brake member along the drive shaft and into frictional engagement with the adjacent surface on the drive wheel

    Magnetic tape transport controlled by rotating transducer heads

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    Magnetic tape transport includes a common drive for both the tape drive capstans and the rotating record/reproduce heads. Speed of the drive may be varied within a preselected range, but, once selected, remains constant so head and capstan are driven in synchronization and at constant speed
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