2,857 research outputs found

    AN ECONOMIC ASSESSMENT OF WETLAND MITIGATION IN NORTHWEST MINNESOTA

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    The economic efficiency of wetland mitigation in Minnesota's Red River Valley was examined using the Minnesota Routine Assessment Method on ten wetland case studies to rate the functions of impacted and replacement wetlands. Secondary sources were used to assign dollar values to wetland functions of impacted and replacement wetlands. Mitigation costs for projects ranged from 279to279 to 4,171 per acre. Estimated annual social values ranged from 207to207 to 1,027 per acre for impacted wetlands and from 268to268 to 927 per acre for replacement wetlands. Social values of replacement wetlands exceeded the social value of impacted wetlands in seven cases. Values of replacement wetlands were 1.8 to 4 times greater than the values of impacted wetlands due to 2-to-1 replacement ratios. When society gains benefits from mitigation, public cost-sharing may be appropriate. In one case the value of the impacted wetlands was higher than the value of the replacement wetland. There were insufficient data to evaluate two cases. Results are only indicators of efficiency, since not all social costs and benefits of the impact-mitigation activity are addressed by legislation. These results suggest wetland mitigation policy in Minnesota needs to be reevaluated if efficient use of society's resources is a legislative goal.Wetland(s), mitigation, economics, values, Minnesota, Red River, Wetland Conservation Act, Minnesota Routine Assessment Method, restoration, Land Economics/Use,

    AN INQUIRY INTO THE RELATIONSHIP OF WETLAND REGULATIONS AND PROPERTY VALUES IN MINNESOTA

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    Ownership in property can be thought of as ownership of the rights to the "incomes" associated with different uses of the property. Each potential use has a separate economic value, which can be ranked if put into money terms. The property's market value is usually held to be the highest income on that ranking. Wetland protection regulations might shift the ownership of some of these rights from private to public entities or restrict the exercise of some rights. This can result in a reduction of the property's market value, if the regulation precludes access to the income from the highest ranking use. A regulation can never increase the economic value of a property from the owner's perspective. Whether or not a reduction in property value is considered "fair" is a question usually left to the courts. If it is determined that a regulation has resulted in a "taking" of property, compensation must be paid. The appropriate level of compensation is the difference between estimated pre- and post-regulation market values. The task of the analyst is to estimate those two values, after first determining if the two uses are feasible given other physical, financial, and legal conditions. Because property prices are not determined until there is a transaction, all such valuations are necessarily estimates based on the professional judgments of the analyst. There are not easy ways to determine these values short of costly individual appraisals or extensive market studies. Wetland regulations in Minnesota do result in reduced values for some property owners--as do all land use regulations. Demonstrating that values went down on regulated properties has policy import, however, only if: (1) the examples are so egregious that the Legislature decides to change the enabling legislation to adjust the distribution of the law's benefits and costs; or (2) the sum of measured property losses exceeds any estimate of total benefits, in which case the Legislature might decide to change the law as not in the broader public interest. Should further property value analyses be conducted? Only if the Legislature is very clear about why it wants to do the study. If the concern is one of fairness, then the distribution of a regulation's costs should be examined by using parcel-by-parcel appraisals or by a careful calculation of the economic benefits and costs among different classes of people, classes of property, or regions of the state. If, on the other hand, the concern is that the aggregate costs of the regulation may exceed its total benefits, then broader economic valuation studies are called for. We are not prepared to recommend either approach at this time, because the Legislature has not yet declared what the problem really is.Land Economics/Use,

    Identifying Structural Variation in Haploid Microbial Genomes from Short-Read Resequencing Data Using Breseq

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    Mutations that alter chromosomal structure play critical roles in evolution and disease, including in the origin of new lifestyles and pathogenic traits in microbes. Large-scale rearrangements in genomes are often mediated by recombination events involving new or existing copies of mobile genetic elements, recently duplicated genes, or other repetitive sequences. Most current software programs for predicting structural variation from short-read DNA resequencing data are intended primarily for use on human genomes. They typically disregard information in reads mapping to repeat sequences, and significant post-processing and manual examination of their output is often required to rule out false-positive predictions and precisely describe mutational events. Results: We have implemented an algorithm for identifying structural variation from DNA resequencing data as part of the breseq computational pipeline for predicting mutations in haploid microbial genomes. Our method evaluates the support for new sequence junctions present in a clonal sample from split-read alignments to a reference genome, including matches to repeat sequences. Then, it uses a statistical model of read coverage evenness to accept or reject these predictions. Finally, breseq combines predictions of new junctions and deleted chromosomal regions to output biologically relevant descriptions of mutations and their effects on genes. We demonstrate the performance of breseq on simulated Escherichia coli genomes with deletions generating unique breakpoint sequences, new insertions of mobile genetic elements, and deletions mediated by mobile elements. Then, we reanalyze data from an E. coli K-12 mutation accumulation evolution experiment in which structural variation was not previously identified. Transposon insertions and large-scale chromosomal changes detected by breseq account for similar to 25% of spontaneous mutations in this strain. In all cases, we find that breseq is able to reliably predict structural variation with modest read-depth coverage of the reference genome (>40-fold). Conclusions: Using breseq to predict structural variation should be useful for studies of microbial epidemiology, experimental evolution, synthetic biology, and genetics when a reference genome for a closely related strain is available. In these cases, breseq can discover mutations that may be responsible for important or unintended changes in genomes that might otherwise go undetected.U.S. National Institutes of Health R00-GM087550U.S. National Science Foundation (NSF) DEB-0515729NSF BEACON Center for the Study of Evolution in Action DBI-0939454Cancer Prevention & Research Institute of Texas (CPRIT) RP130124University of Texas at Austin startup fundsUniversity of Texas at AustinCPRIT Cancer Research TraineeshipMolecular Bioscience

    Lineage dynamics of murine pancreatic development at single-cell resolution.

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    Organogenesis requires the complex interactions of multiple cell lineages that coordinate their expansion, differentiation, and maturation over time. Here, we profile the cell types within the epithelial and mesenchymal compartments of the murine pancreas across developmental time using a combination of single-cell RNA sequencing, immunofluorescence, in situ hybridization, and genetic lineage tracing. We identify previously underappreciated cellular heterogeneity of the developing mesenchyme and reconstruct potential lineage relationships among the pancreatic mesothelium and mesenchymal cell types. Within the epithelium, we find a previously undescribed endocrine progenitor population, as well as an analogous population in both human fetal tissue and human embryonic stem cells differentiating toward a pancreatic beta cell fate. Further, we identify candidate transcriptional regulators along the differentiation trajectory of this population toward the alpha or beta cell lineages. This work establishes a roadmap of pancreatic development and demonstrates the broad utility of this approach for understanding lineage dynamics in developing organs

    Analysis, Visualization, and Transformation of Audio Signals Using Dictionary-based Methods

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    date-added: 2014-01-07 09:15:58 +0000 date-modified: 2014-01-07 09:15:58 +0000date-added: 2014-01-07 09:15:58 +0000 date-modified: 2014-01-07 09:15:58 +000

    Interferometric Constraints on Quantum Geometrical Shear Noise Correlations

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    Final measurements and analysis are reported from the first-generation Holometer, the first instrument capable of measuring correlated variations in space-time position at strain noise power spectral densities smaller than a Planck time. The apparatus consists of two co-located, but independent and isolated, 40 m power-recycled Michelson interferometers, whose outputs are cross-correlated to 25 MHz. The data are sensitive to correlations of differential position across the apparatus over a broad band of frequencies up to and exceeding the inverse light crossing time, 7.6 MHz. By measuring with Planck precision the correlation of position variations at spacelike separations, the Holometer searches for faint, irreducible correlated position noise backgrounds predicted by some models of quantum space-time geometry. The first-generation optical layout is sensitive to quantum geometrical noise correlations with shear symmetry---those that can be interpreted as a fundamental noncommutativity of space-time position in orthogonal directions. General experimental constraints are placed on parameters of a set of models of spatial shear noise correlations, with a sensitivity that exceeds the Planck-scale holographic information bound on position states by a large factor. This result significantly extends the upper limits placed on models of directional noncommutativity by currently operating gravitational wave observatories.Comment: Matches the journal accepted versio

    WALLABY Early Science - I. The NGC 7162 Galaxy Group

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    We present Widefield ASKAP L-band Legacy All-sky Blind Survey (WALLABY) early science results from the Australian Square Kilometre Array Pathfinder (ASKAP) observations of the NGC 7162 galaxy group. We use archival HIPASS and Australia Telescope Compact Array (ATCA) observations of this group to validate the new ASKAP data and the data reduction pipeline ASKAPsoft. We detect six galaxies in the neutral hydrogen (HI) 21-cm line, expanding the NGC 7162 group membership from four to seven galaxies. Two of the new detections are also the first HI detections of the dwarf galaxies, AM 2159-434 and GALEXASC J220338.65-431128.7, for which we have measured velocities of cz=2558cz=2558 and cz=2727cz=2727 km s−1^{-1}, respectively. We confirm that there is extended HI emission around NGC 7162 possibly due to past interactions in the group as indicated by the 40∘40^{\circ} offset between the kinematic and morphological major axes for NGC 7162A, and its HI richness. Taking advantage of the increased resolution (factor of ∌1.5\sim1.5) of the ASKAP data over archival ATCA observations, we fit a tilted ring model and use envelope tracing to determine the galaxies' rotation curves. Using these we estimate the dynamical masses and find, as expected, high dark matter fractions of fDM∌0.81−0.95f_{\mathrm{DM}}\sim0.81-0.95 for all group members. The ASKAP data are publicly available.Comment: 20 pages, 11 figures, accepted for publication in MNRA

    Biogenic carbonate mercury and marine temperature records reveal global influence of Late Cretaceous Deccan Traps

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155784/1/Meyer_et_al_2019_Biogenic_carbonate_mercury.pd
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