2,577 research outputs found
Escape from model-land
Both mathematical modelling and simulation methods in general have contributed greatly to understanding, insight and forecasting in many fields including macroeconomics. Nevertheless, we must remain careful to distinguish model-land and model-land quantities from the real world. Decisions taken in the real world are more robust when informed by estimation of real-world quantities with transparent uncertainty quantification, than when based on “optimal” model-land quantities obtained from simulations of imperfect models optimized, perhaps optimal, in model-land. The authors present a short guide to some of the temptations and pitfalls of model-land, some directions towards the exit, and two ways to escape. Their aim is to improve decision support by providing relevant, adequate information regarding the real-world target of interest, or making it clear why today’s model models are not up to that task for the particular target of interest
NEW AND UPDATED RECORDS FOR AMPHIBIANS AND REPTILES IN MINNESOTA, USA
Following the publication of the revised edition of “Amphibians and Reptiles in Minnesota” by Moriarty and Hall (2014), we accessioned several new or updated records at the Bell Museum of Natural History (JFBM). Records include digital photographs (accession number preceded by “P”) and audio recordings (accession number preceded by “AUD”). In addition, a subset of these observations were accessioned in www.HerpMapper.org. HerpMapper accession numbers are preceded by “HM” and can be viewed online. Benjamin Lowe verified species determinations. Latitude and longitude coordinates are based on datum WGS 84
Consumption-Based Conservation Targeting: Linking Biodiversity Loss to Upstream Demand through a Global Wildlife Footprint.
Although most conservation efforts address the direct, local causes of biodiversity loss, effective long-term conservation will require complementary efforts to reduce the upstream economic pressures, such as demands for food and forest products, which ultimately drive these downstream losses. Here, we present a wildlife footprint analysis that links global losses of wild birds to consumer purchases across 57 economic sectors in 129 regions. The United States, India, China, and Brazil have the largest regional wildlife footprints, while per-person footprints are highest in Mongolia, Australia, Botswana, and the United Arab Emirates. A US$100 purchase of bovine meat or rice products occupies approximately 0.1 km2 of wild bird ranges, displacing 1-2 individual birds, for 1 year. Globally significant importer regions, including Japan, the United Kingdom, Germany, Italy, and France, have large footprints that drive wildlife losses elsewhere in the world and represent important targets for consumption-focused conservation attention
Testing Whether Camera Presence Influences Habitat Specific Predation Pressure on Artificial Shorebird Nests in the Arctic
When monitoring the breeding ecology of birds, the causes and times of nest failure can be difficult to determine. Cameras placed near nests allow for accurate monitoring of nest fate, but their presence may increase the risk of predation by attracting predators, leading to biased results. The relative influence of cameras on nest predation risk may also depend on habitat because predator numbers or behaviour can change in response to the availability or accessibility of nests. We evaluated the impact of camera presence on the predation rate of artificial nests placed within mesic tundra habitats used by Arctic-breeding shorebirds. We deployed 94 artificial nests, half with cameras and half without, during the shorebird-nesting season of 2015 in the East Bay Migratory Bird Sanctuary, Nunavut. Artificial nests were distributed evenly across sedge meadow and supratidal habitats typically used by nesting shorebirds. We used the Cox proportional hazards model to assess differential nest survival in relation to camera presence, habitat type, placement date, and all potential interactions. Artificial nests with cameras did not experience higher predation risk than those without cameras. Predation risk of artificial nests was related to an interaction between habitat type and placement date. Nests deployed in sedge meadows and in supratidal habitats later in the season were subject to a higher risk of predation than those deployed in supratidal habitats early in the season. These differences in predation risk are likely driven by the foraging behaviour of Arctic fox (Vulpes lagopus), a species that accounted for 81% of observed predation events in this study. Arctic fox prey primarily on Arvicoline prey and goose eggs at this site and take shorebird nests opportunistically, perhaps more often later in the season when their preferred prey becomes scarcer. This study demonstrates that, at this site, cameras used for nest monitoring do not influence predation risk. Evaluating the impact of cameras on predation risk is critical prior to their use, as individual study areas may differ in terms of predator species and behaviour.Lors de la surveillance de l’écologie de reproduction des oiseaux, les causes et les périodes de défaillance des nids peuvent être difficiles à déterminer. Des caméras placées près des nids permettent une surveillance précise du sort des nids, mais leur présence peut augmenter le risque de prédation en attirant les prédateurs, ce qui entraîne des résultats biaisés. L’influence relative des caméras sur le risque de prédation des nids peut également dépendre de l’habitat, car le nombre ou le comportement des prédateurs peut changer en fonction de la disponibilité ou de l’accessibilité des nids. Nous avons évalué l’impact de la présence de caméras sur le taux de prédation des nids artificiels placés dans les habitats de la toundra mésique utilisés par les limicoles se reproduisant dans l’Arctique. Nous avons installé 94 nids artificiels, la moitié avec des caméras et l’autre moitié sans caméras, pendant la saison de nidification des limicoles de 2015 dans le Refuge d’oiseaux migrateurs de la baie Est, au Nunavut. Les nids artificiels étaient répartis uniformément dans les cariçaies et les habitats supratidaux généralement utilisés par les limicoles nicheurs. Nous avons utilisé le modèle à risques proportionnels de Cox pour évaluer la survie différentielle des nids en fonction de la présence de caméras, du type d’habitat, de la date d’installation des caméras et de toutes les interactions potentielles. Les nids artificiels équipés de caméras ne présentaient pas de risque de prédation plus élevé que ceux sans caméras. Le risque de prédation des nids artificiels était lié à une interaction entre le type d’habitat et la date d’installation des caméras. Plus tard dans la saison, les nids placés dans les cariçaies et dans les habitats supratidaux ont fait l’objet d’un risque de prédation plus élevé que ceux des habitats supratidaux en début de saison. Ces différences de risque de prédation sont probablement attribuables au comportement d’alimentation du renard arctique (Vulpes lagopus), une espèce qui représentait 81 % des événements de prédation observés dans cette étude. Le renard arctique se nourrit principalement d’arvicolinés et d’oeufs d’oie sur ce site, et s’empare des nids de limicoles de manière opportuniste, peut-être plus souvent plus tard dans la saison, lorsque ses proies préférées se font plus rares. Cette étude démontre que, sur ce site, les caméras servant à la surveillance des nids n’influencent pas le risque de prédation. Il est essentiel d’évaluer l’impact des caméras sur le risque de prédation avant leur utilisation, car chacune des zones étudiées peut différer sur le plan des espèces de prédateurs et des comportements
Investigation of the radiative boundary conditions during the development of the southwest monsoon Saudi Arabian heat low, An
January 1982.Includes bibliographical references.Progress report no. 2 on the cooperative research project between the Department of Atmospheric Science at Colorado State University and the Faculty of Meteorology and Environmental Science at King Abdul-Aziz University in accordance with the CID-ARME TED Project of the University of Arizona. Period covered August 16-November 30, 1981.CID contract #CSU-SA-KAU-02
Promoting Colorectal Cancer Screening Among Haitian Americans
Background: Few studies have examined colorectal cancer screening among Haitian Americans, although striking disparities in colorectal cancer screening and mortality are well-documented among U.S. Blacks. Race, socioeconomic status, and place of birth are factors associated with colorectal cancer incidence and mortality patterns.
Methods: In this article, we summarize published studies on colorectal cancer screening among Haitian Americans, identified through bibliographic searches in PubMed and CINAHL through August 2015, and offer recommendations for further research.
Results: Only one qualitative study and three quantitative surveys have examined colorectal cancer screening among Haitian Americans. A qualitative study found important differences in perceptions of the curability of colorectal cancer, preventive practices, and preferred sources of information among Haitian Americans and other ethnic subgroups of U.S. Blacks. Awareness of colorectal cancer screening tests, risk perception, healthcare provider recommendation, and self-reported use of screening are suboptimal among Haitian Americans and other subgroups. In preliminary quantitative studies, Haitian immigrants have been found to have lower colorectal cancer screening rates than other groups such as African Americans.
Conclusions: Culturally appropriate educational interventions are needed to encourage Haitian American adults aged \u3e 50 years to undergo screening for colorectal cancer and to ensure that they are well informed about the value of healthy eating and physical activity
Clonal and microclonal mutational heterogeneity in high hyperdiploid acute lymphoblastic leukemia.
High hyperdiploidy (HD), the most common cytogenetic subtype of B-cell acute lymphoblastic leukemia (B-ALL), is largely curable but significant treatment-related morbidity warrants investigating the biology and identifying novel drug targets. Targeted deep-sequencing of 538 cancer-relevant genes was performed in 57 HD-ALL patients lacking overt KRAS and NRAS hotspot mutations and lacking common B-ALL deletions to enrich for discovery of novel driver genes. One-third of patients harbored damaging mutations in epigenetic regulatory genes, including the putative novel driver DOT1L (n=4). Receptor tyrosine kinase (RTK)/Ras/MAPK signaling pathway mutations were found in two-thirds of patients, including novel mutations in ROS1, which mediates phosphorylation of the PTPN11-encoded protein SHP2. Mutations in FLT3 significantly co-occurred with DOT1L (p=0.04), suggesting functional cooperation in leukemogenesis. We detected an extraordinary level of tumor heterogeneity, with microclonal (mutant allele fraction <0.10) KRAS, NRAS, FLT3, and/or PTPN11 hotspot mutations evident in 31/57 (54.4%) patients. Multiple KRAS and NRAS codon 12 and 13 microclonal mutations significantly co-occurred within tumor samples (p=4.8x10-4), suggesting ongoing formation of and selection for Ras-activating mutations. Future work is required to investigate whether tumor microheterogeneity impacts clinical outcome and to elucidate the functional consequences of epigenetic dysregulation in HD-ALL, potentially leading to novel therapeutic approaches
Exploration of New Complexity Metrics for Curriculum-Based Measures of Writing
Researchers and practitioners have questioned whether scoring procedures used with curriculum-based measures of writing (CBM-W) capture growth in complexity of writing. We analyzed data from six independent samples to examine two potential scoring metrics for picture word CBM-W (PW), a sentence-level CBM task. Correct word sequences per response (CWSR) and words written per response (WWR) were compared with the current standard metric of correct word sequences (CWS). Linear regression analyses indicated that CWSR predicted scores on standardized norm-referenced criterion measures in more samples than did WWR or CWS. Future studies should explore the capacity of CWSR and WWR to show growth over time, stability, diagnostic accuracy, and utility for instructional decision making
Experimental and computational characterization of a modified GEC cell for dusty plasma experiments
A self-consistent fluid model developed for simulations of micro- gravity
dusty plasma experiments has for the first time been used to model asymmetric
dusty plasma experiments in a modified GEC reference cell with gravity. The
numerical results are directly compared with experimental data and the
experimentally determined dependence of global discharge parameters on the
applied driving potential and neutral gas pressure is found to be well matched
by the model. The local profiles important for dust particle transport are
studied and compared with experimentally determined profiles. The radial forces
in the midplane are presented for the different discharge settings. The
differences between the results obtained in the modified GEC cell and the
results first reported for the original GEC reference cell are pointed out
Comparison of two peptide radiotracers for prostate carcinoma targeting
OBJECTIVES: Scintigraphy is generally not the first choice treatment for prostate cancer, although successful studies using bombesin analog radiopeptides have been performed. Recently, a novel peptide obtained using a phage display library demonstrated an affinity for prostate tumor cells. The aim of this study was to compare the use of a bombesin analog to that of a phage display library peptide (DUP-1) radiolabeled with technetium-99m for the treatment of prostate carcinoma. The peptides were first conjugated to S-acetyl-MAG3 with a 6-carbon spacer, namely aminohexanoic acid. METHODS: The technetium-99m labeling required a sodium tartrate buffer. Radiochemical evaluation was performed using ITLC and was confirmed by high-performance liquid chromatography. The coefficient partition was determined, and in vitro studies were performed using human prostate tumor cells. Biodistribution was evaluated in healthy animals at various time points and also in mice bearing tumors. RESULTS: The radiochemical purity of both radiotracers was greater than 95%. The DUP-1 tracer was more hydrophilic (log P = -2.41) than the bombesin tracer (log P = -0.39). The biodistribution evaluation confirmed this hydrophilicity by revealing the greater kidney uptake of DUP-1. The bombesin concentration in the pancreas was greater than that of DUP-1 due to specific gastrin-releasing peptide receptors. Bombesin internalization occurred for 78.32% of the total binding in tumor cells. The DUP-1 tracer showed very low binding to tumor cells during the in vitro evaluation, although tumor uptake for both tracers was similar. The tumors were primarily blocked by DUP1 and the bombesin radiotracer primarily targeted the pancreas. CONCLUSION: Further studies with the radiolabeled DUP-1 peptide are recommended. With further structural changes, this molecule could become an efficient alternative tracer for prostate tumor diagnosis
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