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Climate adaptation by crop migration.
Many studies have estimated the adverse effects of climate change on crop yields, however, this literature almost universally assumes a constant geographic distribution of crops in the future. Movement of growing areas to limit exposure to adverse climate conditions has been discussed as a theoretical adaptive response but has not previously been quantified or demonstrated at a global scale. Here, we assess how changes in rainfed crop area have already mediated growing season temperature trends for rainfed maize, wheat, rice, and soybean using spatially-explicit climate and crop area data from 1973 to 2012. Our results suggest that the most damaging impacts of warming on rainfed maize, wheat, and rice have been substantially moderated by the migration of these crops over time and the expansion of irrigation. However, continued migration may incur substantial environmental costs and will depend on socio-economic and political factors in addition to land suitability and climate
The Medical Institutional Repositories in Libraries (MIRL) Symposium: a blueprint designed in response to a community of practice need.
BACKGROUND: Health sciences libraries in medical schools, academic health centers, health care networks, and hospitals have established institutional repositories (IRs) to showcase their research achievements, increase visibility, expand the reach of institutional scholarship, and disseminate unique content. Newer roles for IRs include publishing open access journals, tracking researcher productivity, and serving as repositories for data sharing. Many repository managers oversee their IR with limited assistance from others at their institution. Therefore, IR practitioners find it valuable to network and learn from colleagues at other institutions.
CASE PRESENTATION: This case report describes the genesis and implementation of a new initiative specifically designed for a health sciences audience: the Medical Institutional Repositories in Libraries (MIRL) Symposium. Six medical librarians from hospitals and academic institutions in the U.S. organized the inaugural symposium held virtually in November 2021. The goal was to fill a perceived gap in conference programming for IR practitioners in health settings. Themes of the 2021 and subsequent 2022 symposium included IR management, increasing readership and engagement, and platform migration. Post-symposium surveys were completed by 73/238 attendees (31%) in 2021 and by 62/180 (34%) in 2022. Feedback was overwhelmingly positive.
DISCUSSION: Participant responses in post-symposium surveys rated MIRL highly. The MIRL planning group intends to continue the symposium and hopes MIRL will steadily evolve, build community among IR practitioners in the health sciences, and expand the conversation around best practices for digital archiving of institutional content. The implementation design of MIRL serves as a blueprint for collaboratively bringing together a professional community of practice
Metal Abundances in the Magellanic Stream
We report on the first metallicity determination for gas in the Magellanic
Stream, using archival HST GHRS data for the background targets Fairall 9, III
Zw 2, and NGC 7469. For Fairall 9, using two subsequent HST revisits and new
Parkes Multibeam Narrowband observations, we have unequivocally detected the
MSI HI component of the Stream (near its head) in SII1250,1253 yielding a
metallicity of [SII/H]=-0.55+/-0.06(r)+/-0.2(s), consistent with either an SMC
or LMC origin and with the earlier upper limit set by Lu et al. (1994). We also
detect the saturated SiII1260 line, but set only a lower limit of
[SiII/H]>-1.5. We present serendipitous detections of the Stream, seen in
MgII2796,2803 absorption with column densities of (0.5-1)x10^13 cm^-2 toward
the Seyfert galaxies III Zw 2 and NGC 7469. These latter sightlines probe gas
near the tip of the Stream (80 deg down-Stream of Fairall 9). For III Zw 2, the
lack of an accurate HI column density and the uncertain MgIII ionization
correction limits the degree to which we can constrain [Mg/H]; a lower limit of
[MgII/HI]>-1.3 was found. For NGC 7469, an accurate HI column density
determination exists, but the extant FOS spectrum limits the quality of the
MgII column density determination, and we conclude that [MgII/HI]>-1.5.
Ionization corrections associated with MgIII and HII suggest that the
corresponding [Mg/H] may range lower by 0.3-1.0 dex. However, an upward
revision of 0.5-1.0 dex would be expected under the assumption that the Stream
exhibits a dust depletion pattern similar to that seen in the Magellanic
Clouds. Remaining uncertainties do not allow us to differentiate between an LMC
versus SMC origin to the Stream gas.Comment: 30 pages, 8 figures, LaTeX (aaspp4), also available at
http://casa.colorado.edu/~bgibson/publications.html, accepted for publication
in The Astronomical Journa
Thermal And Mechanical Response Of PBX 9501 Under Contact Excitation
The thermal and mechanical responses of a cyclotetramethylene-tetranitramine-based explosive (PBX 9501) and two non-energetic mock materials (900-21 and PBS 9501) under high-frequency mechanical excitation are presented. Direct contact ultrasound transducers were used to excite samples through a frequency range of 50 kHz to 40 MHz. The mechanical response of each sample was approximated from a contact receiving transducer and trends were confirmed via laser Doppler vibrometry. The steady-state thermal response of the samples was measured at discrete excitation frequencies via infrared thermography. A maximum temperature rise of approximately 15 K was observed in PBX 9501, and the mock materials exhibited similar thermal characteristics. Temperature gradients were calculated to estimate the total heat generated within the samples due to the mechanical excitation. The active heating mechanisms were found to be highly dependent on the frequency of excitation. Possible mechanisms of heating at frequencies below 1 MHz are likely related to bulk motion. Above this frequency, the active heating mechanisms are likely related to particle-scale processes. The observed phenomena may prove useful in the aid of current trace vapor detection methods for explosives
Agricultural data management and sharing: Best practices and case study
Agricultural data are crucial to many aspects of production, commerce, and research involved in feeding the global community. However, in most agricultural research disciplines standard best practices for data management and publication do not exist. Here we propose a set of best practices in the areas of peer review, minimal dataset development, data repositories, citizen science initiatives, and support for best data management. We illustrate some of these best practices with a case study in dairy agroecosystems research. While many common, and increasingly disparate data management and publication practices are entrenched in agricultural disciplines, opportunities are readily available for promoting and adopting best practices that better enable and enhance data-intensive agricultural research and production
Multiwaveband Observations of Quasars with Flat Radio Spectra and Strong Millimeter Emission
We present multiwaveband observations of a well selected sample of 28 quasars
and two radio galaxies with flat radio spectra and strong millimeter wave
emission (referred to here as FSRQ's). The observations include multifrequency
VLBI measurements, X-ray observations with ROSAT and submillimeter observations
with the JCMT. Particularly interesting among many findings is a correlation
between the X-ray to millimeter spectral index and fraction of flux density
contained in the VLBI core. This tendency toward higher X-ray fluxes from
sources with stronger jet emission implies that the knots in the jet are the
prominent source of X-rays.Comment: 38 pages, 17 figures, 12 tables, accepted for publication in Ap J
Suppl, May 199
Ropeless fishing to prevent large whale entanglements: Ropeless Consortium report
The 2017 North Atlantic right whale (NARW) unusual mortality event and an increase in humpback whale entanglements off the U.S. West Coast have driven significant interest in ropeless trap/pot fishing. Removing the vertical buoy lines used to mark traps on the sea floor and haul them up would dramatically reduce or eliminate entanglements, the leading cause of NARW mortality, while potentially allowing fishermen to harvest in areas that would otherwise need to be closed to protect whales. At the first annual Ropeless Consortium meeting, researchers, fishing industry representatives, manufacturers, conservationists, and regulators discussed existing and developing technological replacements for the marking and retrieval functions of buoy lines. Fishermen and NGO partners shared their experience demonstrating ropeless systems and provided feedback to improve the designs. U.S. and Canadian federal regulators discussed prospects to use ropeless fishing gear in areas closed to fishing with vertical lines, as well as other options to reduce entanglements, and a Massachusetts official shared additional regulatory considerations involved in ropeless fishing in state waters. Sustainable seafood experts discussed consumer market advantages and endangered, threatened, and protected species impacts in sustainability standards and certifications. Moving forward, there is
an immediate need to (1) work with industry partners to iteratively test and improve ropeless retrieval and marking systems to adapt them to the specific conditions of the relevant trap/pot fisheries, (2) create data sharing and communications protocols for ropeless gear location marking, and (3) develop regulatory procedures and enforcement capacity to allow legal ropeless gear use.This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.2020-06-2
A Clinical Trial to Validate Event-Related Potential Markers of Alzheimer\u27s Disease in Outpatient Settings
INTRODUCTION: We investigated whether event-related potentials (ERP) collected in outpatient settings and analyzed with standardized methods can provide a sensitive and reliable measure of the cognitive deficits associated with early Alzheimer\u27s disease (AD).
METHODS: A total of 103 subjects with probable mild AD and 101 healthy controls were recruited at seven clinical study sites. Subjects were tested using an auditory oddball ERP paradigm.
RESULTS: Subjects with mild AD showed lower amplitude and increased latency for ERP features associated with attention, working memory, and executive function. These subjects also had decreased accuracy and longer reaction time in the target detection task associated with the ERP test.
DISCUSSION: Analysis of ERP data showed significant changes in subjects with mild AD that are consistent with the cognitive deficits found in this population. The use of an integrated hardware/software system for data acquisition and automated data analysis methods make administration of ERP tests practical in outpatient settings
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