61 research outputs found

    Building Global Leaders through Field Research and Extension Experiences in Belize

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    One of the most complex agricultural and natural resources challenges of our time is reconciling sustainable global food security and biodiversity conservation. Providing undergraduate students effective, learning experiences to develop technical and cultural competency prepares them to address this challenge and become global leaders in their disciplines. A three-year experiential research and extension project brought together 14 students and 10 faculty mentors to investigate smallholder farmers practicing conservation-compatible adjacent to the Vaca Forest Reserve in Belize. We used an agroecological approach to foster systems-level thinking and develop transdisciplinary skills of undergraduate students. Students completed applied individual research projects that explored the challenge of food security and biodiversity conservation in the tropics, and worked collaboratively with local stakeholders, design and implement extension projects based on research results. Student and faculty teams assessed cropping and soil management practices; social and economic systems; and wildlife, forestry, and ecosystem services. We assessed student learning outcomes with a tool commonly used for evaluating undergraduate research. Students reported learning gains in attitudes and behaviors toward research, mindset towards research, ability to think and work like a scientist, and research skills. Students also reported positive working relationships with mentors and peers, and a high level of publication and presentation outputs. Students reported that their Belize experience helped develop their agroecological and cross-cultural knowledge and skills, and prepared them for their next career steps. We conclude with recommendations for higher education institutions wishing to develop meaningful global undergraduate research experiences that can build the next generation of leaders

    Can Farmers and Bats Co-exist? Farmer Attitudes, Knowledge, and Experiences with Bats in Belize

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    Bats (Chiroptera) are often viewed negatively by the public. Negative public perceptions of bats may hinder efforts to conserve declining populations. In Belize, the presence of vampire bats (Desmodus rotundus and Diphylla ecaudata) exacerbates the potential for conflicts with humans because of the increased rabies transmission risks. To mitigate these risks, the Belize government provides farmers with assistance to trap and remove vampire bats. In June 2018, we surveyed farmers (n = 44) in and adjacent to the Vaca Forest Reserve in Belize to learn more about their attitudes, knowledge, and experiences with bats. This information may provide new insights and approaches to address farmers’ concerns and enhance bat conservation efforts in Belize. Farmers held negative attitudes toward bats, exhibited low knowledge of their ecosystem services, and supported the trapping and use of toxicants to control bat populations to reduce the risk of rabies transmission between vampire bats and livestock. Farmers with livestock had more negative attitudes toward bats than farmers without livestock. Despite farmers reporting depredation incidences with fruit-eating and vampire bats, farmers expressed more negative attitudes toward vampire bats. We recommend that conservation education efforts target all stakeholders in the reserve to increase awareness about the importance of bats to ecosystems and highlight the dangers of indiscriminate trapping. Cumulatively, this may lead to positive attitude changes toward bats and their conservation

    Code generation for AMReX with applications to numerical relativity

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    We present a new python/SymPy based code generator for producing executable numerical expressions for partial differential equations in AMReX-based applications. We demonstrate the code generator capabilities for the case of 3+13+1 ADM formulations of numerical relativity for the constraint damped, conformal Z4 formulations (Z4c and CCZ4). The generated spacetime solvers are examined for stability and accuracy using a selection of checks from the standard Apples with Apples testbeds for numerical relativity applications. We also explore physically interesting vacuum spacetimes including head-on and inspiraling black hole binary collisions, and investigate the simulated gravitational waveforms from such events with the Newman-Penrose formulation of waveform extraction.Comment: 26 pages, 15 figure

    Public Perceptions of Values Associated with Wildfire Protection at the Wildland-Urban Interface: A Synthesis of National Findings

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    The wildland-urban interface (WUI) continues to transform rural landscapes as previously undeveloped areas are populated with residential and commercial structures which, in turn, impact ecosystems and create landscapes of risk. Within this context, the science of wildfire risk mitigation has experienced renewed and enhanced support among scientists and managers. However, risk mitigation measures have not found purchase in either the public’s acceptance or involvement in this new role of and for fire. This may partially result from little regard for the effects of wildfire prevention efforts on values other than protecting homes and other structures. We report findings from qualitative interviews conducted across the United States to identify and define various values at risk from wildfire. Values influencing risk mitigation emerged from the biophysical, sociodemographic, and sociocultural contexts of wildfire. Findings demonstrate how wildfire is intertwined with diverse sets of risks experienced in daily life. We provide a discussion of how this research impacts the transformation of landscapes and risk management strategies. Identifying and better understanding the effects of values associated with wildfire—and landscape change in the WUI—will allow natural resource managers and decision makers to develop more effective fuel treatment programs and land use policies

    Constraints on Weak Supernova Kicks from Observed Pulsar Velocities

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    Observations of binary pulsars and pulsars in globular clusters suggest that at least some pulsars must receive weak natal kicks at birth. If all pulsars received strong natal kicks above \unit[50]{\kms}, those born in globular clusters would predominantly escape, while wide binaries would be disrupted. On the other hand, observations of transverse velocities of isolated radio pulsars indicate that only 5±2%5\pm2\% have velocities below \unit[50]{\kms}. We explore this apparent tension with rapid binary population synthesis modelling. We propose a model in which supernovae with characteristically low natal kicks (e.g., electron-capture supernovae) only occur if the progenitor star has been stripped via binary interaction with a companion. We show that this model naturally reproduces the observed pulsar speed distribution and without reducing the predicted merging double neutron star yield. We estimate that the zero-age main sequence mass range for non-interacting progenitors of electron-capture supernovae should be no wider than 0.2M{\approx}0.2 M_\odot.Comment: 7 pages including figures, tables, and references. 3 figures including 5 pdfs, and 1 tabl

    Asymmetric ketone hydroboration catalyzed by alkali metal complexes derived from BINOL ligands

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    The ability of alkali metal complexes featuring functionalized BINOL-derived ligands to catalyze ketone hydroboration reactions was explored. The reduced products were formed in excellent yield and with variable enantioselectivities dependent upon the nature of the ligand and the alkali metal cation

    Mass spectrometry-directed structure elucidation and total synthesis of ultra-long chain (O-acyl)-ω-hydroxy fatty acids

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    The (O-acyl)-ω-hydroxy FAs (OAHFAs) comprise an unusual lipid subclass present in the skin, vernix caseosa, and meibomian gland secretions. Although they are structurally related to the general class of FA esters of hydroxy FAs (FAHFAs), the ultra-long chain (30-34 carbons) and the putative -substitution of the backbone hydroxy FA suggest that OAHFAs have unique biochemistry. Complete structural elucidation of OAHFAs has been challenging because of their low abundance within complex lipid matrices. Furthermore, because these compounds occur as a mixture of closely related isomers, insufficient spectroscopic data have been obtained to guide structure confirmation by total synthesis. Here, we describe the full molecular structure of ultra-long chain OAHFAs extracted from human meibum by exploiting the gas-phase purification of lipids through multistage MS and novel multidimensional ion activation methods. The analysis elucidated sites of unsaturation, the stereochemical configuration of carbon-carbon double bonds, and ester linkage regiochemistry. Such isomer-resolved MS guided the first total synthesis of an ultra-long chain OAHFA, which, in turn, confirmed the structure of the most abundant OAHFA found in human meibum, OAHFA 50:2. The availability of a synthetic OAHFA opens new territory for future investigations into the unique biophysical and biochemical properties of these lipids

    DECISIVE Benchmarking Data Report: sUAS Performance Results from Phase I

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    This report reviews all results derived from performance benchmarking conducted during Phase I of the Development and Execution of Comprehensive and Integrated Subterranean Intelligent Vehicle Evaluations (DECISIVE) project by the University of Massachusetts Lowell, using the test methods specified in the DECISIVE Test Methods Handbook v1.1 for evaluating small unmanned aerial systems (sUAS) performance in subterranean and constrained indoor environments, spanning communications, field readiness, interface, obstacle avoidance, navigation, mapping, autonomy, trust, and situation awareness. Using those 20 test methods, over 230 tests were conducted across 8 sUAS platforms: Cleo Robotics Dronut X1P (P = prototype), FLIR Black Hornet PRS, Flyability Elios 2 GOV, Lumenier Nighthawk V3, Parrot ANAFI USA GOV, Skydio X2D, Teal Golden Eagle, and Vantage Robotics Vesper. Best in class criteria is specified for each applicable test method and the sUAS that match this criteria are named for each test method, including a high-level executive summary of their performance.Comment: Approved for public release: PAO #PR2023_74172; arXiv admin note: substantial text overlap with arXiv:2211.0180

    DECISIVE Test Methods Handbook: Test Methods for Evaluating sUAS in Subterranean and Constrained Indoor Environments, Version 1.1

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    This handbook outlines all test methods developed under the Development and Execution of Comprehensive and Integrated Subterranean Intelligent Vehicle Evaluations (DECISIVE) project by the University of Massachusetts Lowell for evaluating small unmanned aerial systems (sUAS) performance in subterranean and constrained indoor environments, spanning communications, field readiness, interface, obstacle avoidance, navigation, mapping, autonomy, trust, and situation awareness. For sUAS deployment in subterranean and constrained indoor environments, this puts forth two assumptions about applicable sUAS to be evaluated using these test methods: (1) able to operate without access to GPS signal, and (2) width from prop top to prop tip does not exceed 91 cm (36 in) wide (i.e., can physically fit through a typical doorway, although successful navigation through is not guaranteed). All test methods are specified using a common format: Purpose, Summary of Test Method, Apparatus and Artifacts, Equipment, Metrics, Procedure, and Example Data. All test methods are designed to be run in real-world environments (e.g., MOUT sites) or using fabricated apparatuses (e.g., test bays built from wood, or contained inside of one or more shipping containers).Comment: Approved for public release: PAO #PR2022_4705
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