7,991 research outputs found

    Climate change and the Delta, San Francisco Estuary and Watershed Science

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    Anthropogenic climate change amounts to a rapidly approaching, “new” stressor in the Sacramento–San Joaquin Delta system. In response to California’s extreme natural hydroclimatic variability, complex water-management systems have been developed, even as the Delta’s natural ecosystems have been largely devastated. Climate change is projected to challenge these management and ecological systems in different ways that are characterized by different levels of uncertainty. For example, there is high certainty that climate will warm by about 2°C more (than late-20th-century averages) by mid-century and about 4°C by end of century, if greenhouse-gas emissions continue their current rates of acceleration. Future precipitation changes are much less certain, with as many climate models projecting wetter conditions as drier. However, the same projections agree that precipitation will be more intense when storms do arrive, even as more dry days will separate storms. Warmer temperatures will likely enhance evaporative demands and raise water temperatures. Consequently, climate change is projected to yield both more extreme flood risks and greater drought risks. Sea level rise (SLR) during the 20th century was about 22cm, and is projected to increase by at least 3-fold this century. SLR together with land subsidence threatens the Delta with greater vulnerabilities to inundation and salinity intrusion. Effects on the Delta ecosystem that are traceable to warming include SLR, reduced snowpack, earlier snowmelt and larger storm-driven streamflows, warmer and longer summers, warmer summer water temperatures, and water-quality changes. These changes and their uncertainties will challenge the operations of water projects and uses throughout the Delta’s watershed and delivery areas. Although the effects of climate change on Delta ecosystems may be profound, the end results are difficult to predict, except that native species will fare worse than invaders. Successful preparation for the coming changes will require greater integration of monitoring, modeling, and decision making across time, variables, and space than has been historically normal

    Soli Deo Gloria: A Doxological Hermeneutic of Mission in Emerging Ministries in the Evangelical Lutheran Church in America

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    This research project is a grounded theory, ethnographic study of emerging ministries in the Evangelical Lutheran Church in America (ELCA). Twenty emerging ministries were selected from within the ELCA. Six of those sites were the subjects of indepth site visits by a research team. Eleven additional sites were the subjects of partial site visits and interviews. The data-gathering phase of the research concluded with a consultation with thirty emerging leaders held at Luther Seminary. Four sensitizing concepts were used as lenses in data gathering: Lutheran, emerging, missional, and doxological hermeneutics. Leadership in emerging ministries and emerging ministries as contextual and indigenous developed as themes in the research. The sociological concept of transculturation as deculturation and neoculturation emerged in support of a grounded theory that transculturation provides a way forward for the ELCA to glorify God through diversity among and within its congregations and ministries. The research question, “How is God glorified in emerging ministries in the Evangelical Lutheran Church in America (ELCA) and in the lives of their people?” developed from the perspective of a doxological hermeneutic of mission. Mission shapes and is shaped by the praying and believing of the church: lex orandi, lex credendi, lex movendi. A doxological hermeneutic of mission is Spirit led, perichoretically discerned, publicly realized, theoretically informed, and biblically/theologically/confessionally framed—soli Deo gloria! And finally, doxology is perichoretic play

    Excess Observed in CDF Bs0μ+μB^0_s \to \mu^{+} \mu^{-} and SUSY at the LHC

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    The recent excess observed by CDF in Bs0μ+μB^0_s \to \mu^{+} \mu^{-} is interpreted in terms of a possible supersymmetric origin. An analysis is given of the parameter space of mSUGRA and non-universal SUGRA models under the combined constraints from LHC-7 with 165 pb1^{-1} of integrated luminosity, under the new XENON-100 limits on the neutralino-proton spin independent cross section and under the CDF Bs0μ+μB^0_s \to \mu^{+} \mu^{-} 90% C.L. limit reported to arise from an excess number of dimuon events. It is found that the predicted value of the branching ratio Bs0μ+μB^0_s \to \mu^{+} \mu^{-} consistent with all the constraints contains the following set of NLSPs: chargino, stau, stop or CP odd (even) Higgs. The lower bounds of sparticles, including those from the LHC, XENON and CDF Bs0μ+μB^0_s\to \mu^+\mu^- constraint, are exhibited and the shift in the allowed range of sparticle masses arising solely due to the extra constraint from the CDF result is given. It is pointed out that the two sided CDF 90% C.L. limit puts upper bounds on sparticle masses. An analysis of possible signatures for early discovery at the LHC is carried out corresponding to the signal region in Bs0μ+μB^0_s \to \mu^{+} \mu^{-}. Implications of GUT-scale non-universalities in the gaugino and Higgs sectors are discussed. If the excess seen by the CDF Collaboration is supported by further data from LHCb or D0, this new result could be a harbinger for the discovery of supersymmetry.Comment: References added, text update

    A new approach for performing contamination control bakeouts in JPL thermal vacuum test chambers

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    Contamination control requirements for the Wide Field/Planetary Camera II (WF/PC II) are necessarily stringent to protect against post-launch contamination of the sensitive optical surfaces, particularly the cold charge coupled device (CCD) imaging surfaces. Typically, thermal vacuum test chambers have employed a liquid nitrogen (LN2) cold trap to collect outgassed contaminants. This approach has the disadvantage of risking recontamination of the test article from shroud offgassing during post-test warmup of the chamber or from any shroud warming of even a few degrees during the bakeout process. By using an enclave, essentially a chamber within a chamber, configured concentrically and internally within an LN2 shroud, a method was developed, based on a design concept by Taylor, for preventing recontamination of test articles during bakeouts and subsequent post-test warmup of the vacuum chamber. Enclaves for testing WF/PC II components were designed and fabricated, then installed in three of JPL's Environmental Test Lab chambers. The design concepts, operating procedures, and test results of this development are discussed

    A Compact Microchip-Based Atomic Clock Based on Ultracold Trapped Rb Atoms

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    We propose a compact atomic clock based on ultracold Rb atoms that are magnetically trapped near the surface of an atom microchip. An interrogation scheme that combines electromagnetically-induced transparency (EIT) with Ramsey's method of separated oscillatory fields can achieve atomic shot-noise level performance of 10^{-13}/sqrt(tau) for 10^6 atoms. The EIT signal can be detected with a heterodyne technique that provides noiseless gain; with this technique the optical phase shift of a 100 pW probe beam can be detected at the photon shot-noise level. Numerical calculations of the density matrix equations are used to identify realistic operating parameters at which AC Stark shifts are eliminated. By considering fluctuations in these parameters, we estimate that AC Stark shifts can be canceled to a level better than 2*10^{-14}. An overview of the apparatus is presented with estimates of duty cycle and power consumption.Comment: 15 pages, 11 figures, 5 table

    Comparative effects of technical-grade and formulated chlorantraniliprole to the survivorship and locomotor activity of the honey bee, \u3ci\u3eApis mellifera\u3c/i\u3e (L.)

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    Background: The loss of honey bee colonies is a nationally recognized problem that demands attention from both the scientific community and the beekeeping industry. One outstanding threat is the unintended exposure of these pollinators to agricultural pesticides. Anthranilic diamides, such as chlorantraniliprole, are registered for use in stone and pome fruits, vegetables, turf, and grains. There are few publicly available studies that provide an analysis of chlorantraniliprole effects on the survivorship and locomotion activity of beneficial, pollinating insects such as honey bees. The data gathered in this study provide the acute toxicity, 30-day survivorship, and locomotor activity of honey bees exposed to technical-grade chlorantraniliprole and three formulated products with chlorantraniliprole as the active ingredient. Results: Neither the technical-grade nor the formulated products of chlorantraniliprole were acutely toxic to honey bees following 4 or 72h treatments at the tested concentrations. A 4 h treatment of technical-grade and formulated chlorantraniliprole did not significantly affect the 30-day survivorship, although significantly higher mortality was observed after 30 days for bees receiving a 72 h treatment of technical-grade chlorantraniliprole and two formulated products. The locomotion activity, or total walking distance, of bees receiving a 4 h treatment of one chlorantraniliprole formulation was significantly reduced, with these individuals recovering their normal locomotion activity at 48 h post exposure. Conversely, there was observed lethargic behavior and significantly reduced walking distances for bees provided with a 72 h treatment of technical-grade chlorantraniliprole and each formulated product. Conclusion: This study provides evidence for the effect of long-term exposure of chlorantraniliprole on the survivorship and locomotor activity of honey bees. Bees receiving a more field-relevant short-term exposure survived and moved similarly to untreated bees, reiterating the relative safety of chlorantraniliprole exposure to adult honey bees at recommended label concentrations
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