47 research outputs found
Modeling Landowner Interactions and Development Patterns at the Urban Fringe
Population growth and unrestricted development policies are driving low-density urbanization and fragmentation of peri-urban landscapes across North America. While private individuals own most undeveloped land, little is known about how their decision-making processes shape landscape-scale patterns of urbanization over time. We introduce a hybrid agent-based modeling (ABM) â cellular automata (CA) modeling approach, developed for analyzing dynamic feedbacks between landownersâ decisions to sell their land for development, and resulting patterns of landscape fragmentation. Our modeling approach builds on existing conceptual frameworks in land systems modeling by integrating an ABM into an established grid-based land-change model â FUTURES. The decision-making process within the ABM involves landowner agents whose decision to sell their land to developers is a function of heterogeneous preferences and peer-influences (i.e., spatial neighborhood relationships). Simulating landownersâ decision to sell allows an operational link between the ABM and the CA module. To test our hybrid ABM-CA approach, we used empirical data for a rapidly growing region in North Carolina for parameterization. We conducted a sensitivity analysis focusing on the two most relevant parametersâspatial actor distribution and peer-influence intensityâand evaluated the dynamic behavior of the model simulations. The simulation results indicate different peer-influence intensities lead to variable landscape fragmentation patterns, suggesting patterns of spatial interaction among landowners indirectly affect landscape-scale patterns of urbanization and the fragmentation of undeveloped forest and farmland
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Beyond the Refugee Crisis how the UK news media represent asylum seekers across national boundaries
Migration is one of the most pressing, divisive issues in global politics today, and media play a crucial role in how communities understand and respond. This study examines how UK newspapers (n = 974) and popular news websites (n = 1044) reported on asylum seekers throughout 2017. It contributes to previous literature in two important ways. First, by examining the ânew normalâ of daily news coverage in the wake of the 2015 ârefugee crisisâ in Europe. Second, by looking at how asylum seekers from different regions are represented. The content analysis finds significant variations in how asylum seekers are reported, including terminology use and topics they are associated with. The paper also identifies important commonalities in how all asylum seekers are represented - most notably, the dominance of political elites as sources across all media content. It argues that Entmanâs âcascade network modelâ can help to explain this, with elites in one country able to influence transnational reports
Do Author-Suggested Reviewers Rate Submissions More Favorably than Editor-Suggested Reviewers? A Study on Atmospheric Chemistry and Physics
Background: Ratings in journal peer review can be affected by sources of bias. The bias variable investigated here was the information on whether authors had suggested a possible reviewer for their manuscript, and whether the editor had taken up that suggestion or had chosen a reviewer that had not been suggested by the authors. Studies have shown that authorsuggested reviewers rate manuscripts more favorably than editor-suggested reviewers do. Methodology/Principal Findings: Reviewers â ratings on three evaluation criteria and the reviewers â final publication recommendations were available for 552 manuscripts (in total 1145 reviews) that were submitted to Atmospheric Chemistry and Physics, an interactive open access journal using public peer review (authors â and reviewers â comments are publicly exchanged). Public peer review is supposed to bring a new openness to the reviewing process that will enhance its objectivity. In the statistical analysis the quality of a manuscript was controlled for to prevent favorable reviewers â ratings from being attributable to quality instead of to the bias variable. Conclusions/Significance: Our results agree with those from other studies that editor-suggested reviewers rated manuscripts between 30 % and 42 % less favorably than author-suggested reviewers. Against this backdrop journal editors should consider either doing without the use of author-suggested reviewers or, if they are used, bringing in more than one editor-suggested reviewer for the review process (so that the review by author-suggested reviewers can be put i
Stepped-wedge randomised trial of laparoscopic ventral mesh rectopexy in adults with chronic constipation: Study protocol for a randomized controlled trial
BACKGROUND: Laparoscopic ventral mesh rectopexy (LVMR) is an established treatment for external full-thickness rectal prolapse. However, its clinical efficacy in patients with internal prolapse is uncertain due to the lack of high-quality evidence. METHODS: An individual level, stepped-wedge randomised trial has been designed to allow observer-blinded data comparisons between patients awaiting LVMR with those who have undergone surgery. Adults with symptomatic internal rectal prolapse, unresponsive to prior conservative management, will be eligible to participate. They will be randomised to three arms with different delays before surgery (0, 12 and 24 weeks). Efficacy outcome data will be collected at equally stepped time points (12, 24, 36 and 48 weeks). The primary objective is to determine clinical efficacy of LVMR compared to controls with reduction in the Patient Assessment of Constipation Quality of Life (PAC-QOL) at 24 weeks serving as the primary outcome. Secondary objectives are to determine: (1) the clinical effectiveness of LVMR to 48 weeks to a maximum of 72 weeks; (2) pre-operative determinants of outcome; (3) relevant health economics for LVMR; (4) qualitative evaluation of patient and health professional experience of LVMR and (5) 30-day morbidity and mortality rates. DISCUSSION: An individual-level, stepped-wedge, randomised trial serves the purpose of providing an untreated comparison for the active treatment group, while at the same time allowing the waiting-listed participants an opportunity to obtain the intervention at a later date. In keeping with the basic ethical tenets of this design, the average waiting time for LVMR (12 weeks) will be shorter than that for routine services (24 weeks)
Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial
Background
Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy
Incisional hernia following colorectal cancer surgery according to suture technique: Hughes Abdominal Repair Randomized Trial (HART).
BACKGROUND: Incisional hernias cause morbidity and may require further surgery. HART (Hughes Abdominal Repair Trial) assessed the effect of an alternative suture method on the incidence of incisional hernia following colorectal cancer surgery. METHODS: A pragmatic multicentre single-blind RCT allocated patients undergoing midline incision for colorectal cancer to either Hughes closure (double far-near-near-far sutures of 1 nylon suture at 2-cm intervals along the fascia combined with conventional mass closure) or the surgeon's standard closure. The primary outcome was the incidence of incisional hernia at 1 year assessed by clinical examination. An intention-to-treat analysis was performed. RESULTS: Between August 2014 and February 2018, 802 patients were randomized to either Hughes closure (401) or the standard mass closure group (401). At 1 year after surgery, 672 patients (83.7 per cent) were included in the primary outcome analysis; 50 of 339 patients (14.8 per cent) in the Hughes group and 57 of 333 (17.1 per cent) in the standard closure group had incisional hernia (OR 0.84, 95 per cent c.i. 0.55 to 1.27; Pâ=â0.402). At 2 years, 78 patients (28.7 per cent) in the Hughes repair group and 84 (31.8 per cent) in the standard closure group had incisional hernia (OR 0.86, 0.59 to 1.25; Pâ=â0.429). Adverse events were similar in the two groups, apart from the rate of surgical-site infection, which was higher in the Hughes group (13.2 versus 7.7 per cent; OR 1.82, 1.14 to 2.91; Pâ=â0.011). CONCLUSION: The incidence of incisional hernia after colorectal cancer surgery is high. There was no statistical difference in incidence between Hughes closure and mass closure at 1 or 2 years. REGISTRATION NUMBER: ISRCTN25616490 (http://www.controlled-trials.com)
Ephemeral Masculinities? Tracking Men, Partners and Fathers in the Geography of Family Holidays
The discussion presented in the following pages is anchored in data derived from a broader sociological study into contemporary family rituals. The core argument is that in heterosexual couples, the familyâcentred holidays presents an opportunity for the everyday gendered division of domestic labour and children care work to be negotiated and temporarily restructured. Through its focus on the role men play in family holidays, this chapter makes an important contribution to debates about masculinity, travel and familial relationships within heterosexual couples. While one needs to be attentive to the complex realities of the modern family life and intra-family relations towards travel and tourism, studying the traditional nuclear family remains an exciting and fruitful work to the extent that one cannot neglect the fact that this model is (still) behind many experiences and representations of families on holidays
Characterizing Spatial Pattern and Heterogeneity of Pine Forests in North Carolinaâs Coastal Plain using LiDAR
Remote sensing tools that directly characterize canopy structure would be beneficial for management activities and conservation planning. LiDAR (Light Detection And Ranging) is such a tool, as an active remote sensing technology that provides fine-grained information about the three-dimensional structure of ecosystems across a broad spatial extent.
This project assesses the feasibility of using the state-wide North Carolina Floodplain Mapping LiDAR dataset to differentiate between the structural components of evergreen forest types in North Carolinaâs coastal plain. Vertical structure and spatial patterns of vertical structure were quantified using geospatial measures such as semivariogram/ correlograms, lacunarity analysis, and correlation length. LiDAR-derived metrics were also created for comparison with standard field-based measurements of stand structure. I found that LiDAR is capable of measuring canopy variation and can differentiate between the structural characteristics of evergreen forest types. Also, the N.C. LiDAR has potential for use as a surrogate for field measurements when collection is not feasible due to time, labor, or financial constraints. In addition, the project examined LiDARâs use as a screening tool in the identification of suitable habitat for the federally endangered red-cockaded woodpecker (Picoides borealis). I used Maximum Entropy (Maxent), an inductive modeling algorithm for presence data only, to create a spatial species distribution model using LiDAR-derived variables in addition to more typical geospatial variables. The Area (AUC) under the Receiver Operating Characteristic (ROC) curve was analyzed for increases in predictive power with additions of variables. Results suggested that the addition of LiDAR-derived variables to habitat models improved their predictive power, resulting in a test AUC increase from 0.923 with standard spatial variables only, to a test AUC of 0.951 with LiDAR-derived variables added. The success of this project has important implications for natural resource management and conservation planning, especially given that the LiDAR dataset is publicly available and covers the entire state of North Carolina
Uncovering Trends and Spatial Biases of Research in a U.S. National Park
National parks are vital public resources for the preservation of species and landscapes, and for decades have provided natural laboratories for studying environmental and cultural resources. Though significant scholarship has taken place in national parks, syntheses of research trends and biases are rarely available for needs assessments and decision making. In this paper, we demonstrate procedures to close this information gap using Congaree National Park (CNP) as an example of a protected area characterized by disparate research. We conducted a systematic review of research topics and funding sources of all peer-reviewed, published research conducted since its inception as a National Monument in 1976. We next paired our evaluation of research trends with a spatial analysis of study locations to uncover patterns and biases in research. A total of 49 peer-reviewed publications describing research conducted at CNP have been published between 1976â2018, with over 75% published since 2003. Quantitative studies accounted for nearly 90% of all studies, and vegetation was the most commonly studied discipline. Most studies were funded by federal agencies, with the National Park Service providing the most funding instances. Spatial analyses revealed statistically significant (p < 0.05) hotspots of studies near the park entrance, visitor center, roads, and hiking trails. In providing a comprehensive evaluation of research patterns and trends within a single park, we developed an approach that can be applied by managers in other parks or public lands to maximize the utility of past research, identify potentially valuable but understudied park resources, and prioritize research needs