388 research outputs found

    A revision of the generic classification of the family Echinoceratidae (Cephalopoda, Ammonoidea) (Lower Jurassic)

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    38 p., 5 pl., 4 fig.http://paleo.ku.edu/contributions.htm

    Mobile telephone-delivered contingency management interventions promoting behaviour change in individuals with substance use disorders: a meta-analysis

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    BACKGROUND/AIMS: Contingency management (CM) interventions have gained considerable interest due to their success in the treatment of addiction. However, their implementation can be resource-intensive for clinical staff. Mobile telephone-based systems might offer a low-cost alternative. This approach could facilitate remote monitoring of behaviour and delivery of the reinforcer and minimize issues of staffing and resources. This systematic review and meta-analysis assessed the evidence for the effectiveness of mobile telephone-delivered CM interventions to promote abstinence (from drugs, alcohol and tobacco), medication adherence and treatment engagement among individuals with substance use disorders. DESIGN: A systematic search of databases (PsychINFO, CINAHL, MEDLINE PubMed, CENTRAL, Embase) for randomized controlled trials and within-subject design studies (1995-2019). The review was conducted in accordance with the PRISMA statement. The protocol was registered on PROSPERO. SETTING: All included studies originated in the United states. PARTICIPANTS: Seven studies were found, including 222 participants; two targeted alcohol abstinence among frequent drinkers and four targeted smoking cessation (in homeless veterans and those with post-traumatic stress disorder). One targeted medication adherence. MEASURES: The efficacy of CM to increase alcohol and nicotine abstinence was compared with control using several outcomes; percentage of negative samples (PNS), quit rate (QR) and longest duration abstinent (LDA) at the end of the intervention. FINDINGS: The random-effects meta-analyses produced pooled effect sizes of; PNS [d = 0.94, 95% confidence interval (CI) = 0.63-1.25], LDA (d = 1.08, 95% CI = 0.69-1.46) and QR (d = 0.46, 95% CI = 0.27-0.66), demonstrating better outcomes across the CM conditions. Most of the studies were rated as of moderate quality. 'Fail-safe N' computations for PNS indicated that 50 studies would be needed to produce a non-significant overall effect size. None could be calculated for QR and LDA due to insufficient number of studies. CONCLUSION: Mobile telephone-delivered contingency management performs significantly better than control conditions in reducing tobacco and alcohol use among adults not in treatment for substance use disorders

    ALTRUISM VIA KIN-SELECTION STRATEGIES THAT RELY ON ARBITRARY TAGS WITH WHICH THEY COEVOLVE

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    Hamilton's rule explains when natural selection will favor altruism between conspecifics, given their degree of relatedness. In practice, indicators of relatedness (such as scent) coevolve with strategies based on these indicators, a fact not included in previous theories of kin recognition. Using a combination of simulation modeling and mathematical extension of Hamilton's rule, we demonstrate how altruism can emerge and be sustained in a coevolutionary setting where relatedness depends on an individual's social environment and varies from one locus to another. The results support a very general expectation of widespread, and not necessarily weak, conditional altruism in nature.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72180/1/j.0014-3820.2004.tb00465.x.pd

    A Miniature Laser Desorption/Ionization Time-of-Flight Mass Spectrometer for in Situ Analysis of Mars Surface Composition and Identification of Hazard in Advance of Future Manned Exploration

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    Future landed missions to Mars will be guided by two strategic directions: (1) sample return to Earth, for comprehensive compositional analyses, as recommended by the 2011 NRC Planetary Decadal Survey; and (2) preparation for human exploration in the 2030s and beyond, as laid out by US space policy. The resultant mission architecture will likely require high-fidelity in situ chemical/organic sample analyses within an extremely constrained resource envelope. Both science goals (e.g., MEPAG Goal 1, return sample selection, etc.) as well as identification of any potential toxic and biological hazards to humans, must be addressed. Over the past several years of instrument development, we have found that the adaptable, compact, and highly capable technique of laser desorption/ionization time-of-flight mass spectrometry (LD-TOF-MS) has significant potential to contribute substantially to these dual objectives. This concept thus addresses Challenge Area 1: instrumentation and Investigation Approaches

    Initial Studies of the Bidirectional Reflectance Distribution Function of Multi-Walled Carbon Nanotube Structures for Stray Light Control Applications

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    The presentation examines the application of low reflectance surfaces in optical instruments, multi-walled carbon nanotubes (MWCNTs), research objects, MWCNT samples, measurement of 8 deg. directional/hemispherical reflectance, measurement of bidirectional reflectance distribution function (BRDF), and what is current the "blackest ever black"

    Performance of a Carbon Nanotube Field Emission Electron Gun

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    A cold cathode field emission electron gun (e-gun) based on a patterned carbon nanotube (CNT) film has been fabricated for use in a miniaturized reflectron time-of-flight mass spectrometer (RTOF MS). Performance of the CNT e-gun has been evaluated. A traditional thermionic electron gun has also been fabricated and evaluated in parallel and its performance is used as a benchmark in the evaluation of our CNT e-gun. Implications for future improvements and integration into the RTOF MS are discussed

    Simulation of a Miniature, Low-Power Time-of-Flight Mass Spectrometer for In Situ Analysis of Planetary Atmospheres

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    We are implementing nano- and micro-technologies to develop a miniaturized electron impact ionization mass spectrometer for planetary science. Microfabrication technology is used to fabricate the ion and electron optics, and a carbon nanotube (CNT) cathode is used to generate the ionizing electron beam. Future NASA planetary science missions demand miniaturized, low power mass spectrometers that exhibit high resolution and sensitivity to search for evidence of past and present habitability on the surface and in the atmosphere of priority targets such as Mars, Titan, Enceladus, Venus, Europa, and short-period comets. Toward this objective, we are developing a miniature, high resolution reflectron time-of-flight mass spectrometer (Mini TOF-MS) that features a low-power CNT field emission electron impact ionization source and microfabricated ion optics and reflectron mass analyzer in a parallel-plate geometry that is scalable. Charged particle electrodynamic modeling (SIMION 8.0.4) is employed to guide the iterative design of electron and ion optic components and to characterize the overall performance of the Mini TOF-MS device via simulation. Miniature (less than 1000 cubic centimeters) TOF-MS designs (ion source, mass analyzer, detector only) demonstrate simulated mass resolutions greater than 600 at sensitivity levels on the order of 10(exp -3) cps/molecule N2/cc while consuming 1.3 W of power and are comparable to current spaceflight mass spectrometers. Higher performance designs have also been simulated and indicate mass resolutions approximately 1000, though at the expense of sensitivity and instrument volume

    Laser Time-of-Flight Mass Spectrometry for Future In Situ Planetary Missions

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    Laser desorption/ionization time-of-flight mass spectrometry (LD-TOF-MS) is a versatile, low-complexity instrument class that holds significant promise for future landed in situ planetary missions that emphasize compositional analysis of surface materials. Here we describe a 5kg-class instrument that is capable of detecting and analyzing a variety of analytes directly from rock or ice samples. Through laboratory studies of a suite of representative samples, we show that detection and analysis of key mineral composition, small organics, and particularly, higher molecular weight organics are well suited to this instrument design. A mass range exceeding 100,000 Da has recently been demonstrated. We describe recent efforts in instrument prototype development and future directions that will enhance our analytical capabilities targeting organic mixtures on primitive and icy bodies. We present results on a series of standards, simulated mixtures, and meteoritic samples

    Plasma Electronics

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    Contains reports on ten research projects.U. S. Air Force under Contract AF 19(628)-500U. S. Atomic Energy Commission under Contract AT(30-1)-3211U. S. Atomic Energy Commission under Contract AT(30-1)-3221National Science Foundation (Grant G-24073)Lincoln Laboratory, Purchase Order DDL BB-10

    Plasma Electronics

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    Contains reports on eight research projects.National Science Foundation (Grant G-24073)United States Atomic Energy Commission (Contract AF(30-1)-3285)Lincoln Laboratory (Purchase Order DDL BB-107)United States Air Force (Contract AF19(628)-500)United States Atomic Energy Commission (Contract AT(30-1)-3221
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