240 research outputs found
The Railroadâs Impact on Land Values in the Upper Great Plains at the Closing of the Frontier
We show that the impact of transportation improvements on land values is complex with a direct, positive relationship on the price of land and also a positive relationship with the ratio of improved acres to total acres, another important influence on the per acre price of land. We construct a two step estimation that removes the impact of transportation outlets on the ratio of improved to total acres before including the transportation variables and the adjusted ratio variable as independent variables in a regression on price per acre. This estimation gives us the expected positive impact of railroads on land price. We also use Box-Cox regressions to show the semi-log form, a common model specification, may be inappropriate for our data and possibly then for other land price research.Box-Cox, Railroads, Great Plains
Environmental Inspection Proclivity and State Manufacturing Growth: The US Experience from the 1990s
In this paper we construct a ranking of states based on their proclivity to inspect facilities for environmental compliance. Our measure utilizes state-level inspections data supplied by the US Environmental Protection Agency. After developing our ranking, we use it to predict state-level growth in manufacturing establishments. In doing so, we find support for the notion that enforcement intensity adversely impacts such growth. Our results offer insight into why existing studies that examine the impact of environmental regulation on location and growth produce inconsistent results.Monitoring and Enforcement, Environmental Regulations, Business Formation Growth
The Economic and Fiscal Impacts of Immigrant Populations on Nebraska and Omaha: Evidence from the 2015-2019 American Community Survey
Few public policy topics generate as much impassioned debate as immigration. While arguments abound regarding the motivations for and efficacy of these policies, there are nonetheless many possible consequences of their implementation. This study focuses on only one specific question: What is the economic impact of immigrants on job creation and economic growth and development in Nebraska and the Omaha Metropolitan Statistical Area (MSA). To that end, using the US Census Bureauâs American Community Survey (ACS) data for the sample periods 2015 to 2019, this report quantitatively assesses this economic impact. While much of the focus in this study is on the total international immigrant group, with particular attention is paid to those immigrants from Mexico, Central America, South America, and the Caribbean Findings indicate a substantial economic impact from these immigrant groups from a variety of perspectives. For example, immigrant labor in the construction, food services, and animal slaughtering and processing generate substantial impacts. In the Omaha MSA, this employment generated 5.2 billion in production and 26,261 jobs. In Nebraska, total foreign born employment generated 16.1 billion in production and 79,516 jobs. Whatever the policy outcomes regarding immigration become, a recognition of these groupsâ economic contributions must be kept firmly in mind
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Is Sacral Extension a Risk Factor for Early Proximal Junctional Kyphosis in Adult Spinal Deformity Surgery?
Study designRetrospective cohort study.PurposeTo investigate the role of sacral extension (SE) for the development of proximal junctional kyphosis (PJK) in adult spinal deformity (ASD) surgery.Overview of literatureThe development of PJK is multifactorial and different risk factors have been identified. Of these, there is some evidence that SE also affects the development of PJK, but data are insufficient.MethodsUsing a combined database comprising two propensity-matched groups of fusions following ASD surgery, one with fixation to S1 or S1 and the ilium (SE) and one without SE but with a lower instrumented vertebra of L5 or higher (lumbar fixation, LF), PJK and the role of further parameters were analyzed. The propensity-matched variables included age, the upper-most instrumented vertebra (UIV), preoperative sagittal alignment, and the baseline to one year change of the sagittal alignment.ResultsPropensity matching led to two groups of 89 patients each. The UIV, pelvic incidence minus lumbar lordosis, sagittal vertical axis, pelvic tilt, age, and body mass index were similar in both groups (p >0.05). The incidence of PJK at postoperative one year was similar for SE (30.3%) and LF (22.5%) groups (p =0.207). The PJK angle was comparable (p =0.963) with a change of -8.2° (SE) and -8.3° (LF) from the preoperative measures (p =0.954). A higher rate of PJK after SE (p =0.026) was found only in the subgroup of patients with UIV levels between T9 and T12.ConclusionsInstrumentation to the sacrum with or without iliac extension did not increase the overall risk of PJK. However, an increased risk for PJK was found after SE with UIV levels between T9 and T12
Analysis of methods
Information is one of an organization's most important assets. For this reason the development and maintenance of an integrated information system environment is one of the most important functions within a large organization. The Integrated Information Systems Evolution Environment (IISEE) project has as one of its primary goals a computerized solution to the difficulties involved in the development of integrated information systems. To develop such an environment a thorough understanding of the enterprise's information needs and requirements is of paramount importance. This document is the current release of the research performed by the Integrated Development Support Environment (IDSE) Research Team in support of the IISEE project. Research indicates that an integral part of any information system environment would be multiple modeling methods to support the management of the organization's information. Automated tool support for these methods is necessary to facilitate their use in an integrated environment. An integrated environment makes it necessary to maintain an integrated database which contains the different kinds of models developed under the various methodologies. In addition, to speed the process of development of models, a procedure or technique is needed to allow automatic translation from one methodology's representation to another while maintaining the integrity of both. The purpose for the analysis of the modeling methods included in this document is to examine these methods with the goal being to include them in an integrated development support environment. To accomplish this and to develop a method for allowing intra-methodology and inter-methodology model element reuse, a thorough understanding of multiple modeling methodologies is necessary. Currently the IDSE Research Team is investigating the family of Integrated Computer Aided Manufacturing (ICAM) DEFinition (IDEF) languages IDEF(0), IDEF(1), and IDEF(1x), as well as ENALIM, Entity Relationship, Data Flow Diagrams, and Structure Charts, for inclusion in an integrated development support environment
Remote sensing of fish-processing in the Sundarbans Reserve Forest, Bangladesh: an insight into the modern slavery-environment nexus in the coastal fringe
© 2020, The Author(s). Land-based fish-processing activities in coastal fringe areas and their social-ecological impacts have often been overlooked by marine scientists and antislavery groups. Using remote sensing methods, the location and impacts of fish-processing activities were assessed within a case study of Bangladeshâs Sundarbans mangrove forests. Ten fish-processing camps were identified, with some occurring in locations where human activity is banned. Environmental degradation included the removal of mangroves, erosion, and the destruction of protected areas. Previous studies have identified cases of labour exploitation and modern slavery occurring within the Sundarbans, and remote sensing was used to triangulate these claims by providing spatial and temporal analysis to increase the understanding of the operational trends at these locations. These findings were linked to the cyclical relationship between modern slavery and environmental degradation, whereby environmental damage is both a driver and result of workers subjected to modern slavery. Remote sensing can be used as an additional methodological tool to support the achievement of the Sustainable Development Goals (SDGs) and provide evidence to support the promotion of the âfreedom dividendâ which would have far-reaching economic, social, cultural, and environmental benefits. Satellite remote sensing is likely to play an important role going forward for understanding these issues but should be augmented with ground-based data collection methods
Detection and isolation of disseminated tumor cells in bone marrow of patients with clinically localized prostate cancer
BackgroundDisseminated tumor cells (DTCs) have been reported in the bone marrow (BM) of patients with localized prostate cancer (PCa). However, the existence of these cells continues to be questioned, and few methods exist for viable DTC isolation. Therefore, we sought to develop novel approaches to identify and, if detected, analyze localized PCa patient DTCs.MethodsWe used fluorescenceâactivated cell sorting (FACS) to isolate a putative DTC population, which was negative for CD45, CD235a, alkaline phosphatase, and CD34, and strongly expressed EPCAM. We examined tumor cell content by bulk cell RNA sequencing (RNAâSeq) and wholeâexome sequencing after whole genome amplification. We also enriched for BM DTCs with αâEPCAM immunomagnetic beads and performed quantitative reverse trancriptase polymerase chain reaction (qRTâPCR) for PCa markers.ResultsAt a threshold of 4 cells per million BM cells, the putative DTC population was present in 10 of 58 patients (17%) with localized PCa, 4 of 8 patients with metastatic PCa of varying disease control, and 1 of 8 patients with no known cancer, and was positively correlated with patientsâ plasma PSA values. RNAâSeq analysis of the putative DTC population collected from samples above (3 patients) and below (5 patients) the threshold of 4 putative DTCs per million showed increased expression of PCa marker genes in 4 of 8 patients with localized PCa, but not the one normal donor who had the putative DTC population present. Wholeâexome sequencing also showed the presence of single nucleotide polymorphisms and structural variants in the gene characteristics of PCa in 2 of 3 localized PCa patients. To examine the likely contaminating cell types, we used a myeloid colony formation assay, differential counts of cell smears, and analysis of the RNAâSeq data using the CIBERSORT algorithm, which most strongly suggested the presence of Bâcell lineages as a contaminant. Finally, we used EPCAM enrichment and qRTâPCR for PCa markers to estimate DTC prevalence and found evidence of DTCs in 21 of 44 samples (47%).ConclusionThese data support the presence of DTCs in the BM of a subset of patients with localized PCa and describe a novel FACS method for isolation and analysis of viable DTCs.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151343/1/pros23896.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151343/2/pros23896_am.pd
Growing evidence of the interconnections between modern slavery, environmental degradation, and climate change
The modern slaveryâenvironmental degradationâclimate change nexus may threaten the achievement of the Sustainable Development Goals (SDGs). Globally, approximately 12.2 million workers are entrapped in modern slavery in environmentally degrading activities, and SDG target 8.7 (the elimination of all forms of modern slavery) may be instrumental in accelerating attainment of other SDG targets. However, without appropriate mitigation strategies, the attainment of some of the SDG's environmental targets may also negatively influence progress on 8.7. Unfortunately, these feedbacks are poorly understood and data are limited and difficult to obtain. In this perspective we show how an SDG interaction framework may help overcome these data challenges by signaling how potential policy action and other interventions would influence progress on 8.7 and other environmental targets based on known processes and patterns. This understanding is crucial to move beyond data limitations, direct future research, and develop an often-lacking evidence-base to effect holistic change
Discovery and Early Evolution of ASASSN-19bt, the First TDE Detected by TESS
We present the discovery and early evolution of ASASSN-19bt, a tidal
disruption event (TDE) discovered by the All-Sky Automated Survey for
Supernovae (ASAS-SN) at a distance of Mpc and the first TDE to be
detected by TESS. As the TDE is located in the TESS Continuous Viewing Zone,
our dataset includes 30-minute cadence observations starting on 2018 July 25,
and we precisely measure that the TDE begins to brighten days before
its discovery. Our dataset also includes 18 epochs of Swift UVOT and XRT
observations, 2 epochs of XMM-Newton observations, 13 spectroscopic
observations, and ground data from the Las Cumbres Observatory telescope
network, spanning from 32 days before peak through 37 days after peak.
ASASSN-19bt thus has the most detailed pre-peak dataset for any TDE. The TESS
light curve indicates that the transient began to brighten on 2019 January 21.6
and that for the first 15 days its rise was consistent with a flux power-law model. The optical/UV emission is well-fit by a blackbody SED,
and ASASSN-19bt exhibits an early spike in its luminosity and temperature
roughly 32 rest-frame days before peak and spanning up to 14 days that has not
been seen in other TDEs, possibly because UV observations were not triggered
early enough to detect it. It peaked on 2019 March 04.9 at a luminosity of
ergs s and radiated
ergs during the 41-day rise to peak. X-ray observations after peak indicate a
softening of the hard X-ray emission prior to peak, reminiscent of the
hard/soft states in X-ray binaries.Comment: 23 pages, 14 figures, 5 tables. A machine-readable table containing
the host-subtracted photometry presented in this manuscript is included as an
ancillary fil
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