1,106 research outputs found

    Using precision agriculture field data to evaluate combine harvesting efficiency

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    Soybeans must be harvested during a limited time period using expensive combines and associated equipment. Maximizing combine field efficiency, the ratio of the actual harvesting capacity to theoretical harvesting capacity, is an important objective of machinery managers. Spatial and temporal yield data from a 2012 CaseIH 8120 Axial-Flow combine equipped with a 9 meter MacDon D-65 Draper header and the Case-IH Advanced Farming System (AFS) yield monitoring system were used to examine field efficiency when harvesting soybean in three Arkansas Delta irrigated soybean fields during the 2015 season. Time efficiencies (TE) in the three fields ranged from 72.9% to 85.8% (mean = 80.9%, standard deviation (SD) = 9.6%); width efficiencies (WE) ranged from 96.7% to 98.8% (mean = 97.6%, SD = 1.6%); and overall field efficiencies (FE) ranged from 70.4% to 84.8% (mean = 79.0%, SD = 9.7%). Contrary to expectations, neither row length nor unadjusted yield was significantly correlated (P \u3c 0.05) with time efficiency, width efficiency, or field efficiency. Time efficiency explained 90.5% (sr2 = 0.905) of the unique variance in field efficiency, while WE explained only 1.6% (sr2 = 0.016) of the variance in FE when controlling for the effects of TE. Results indicated that the use of geo-referenced field and performance data can be helpful in evaluating combine performance and efficiency

    Cascadia Fore Arc Seismic Survey: Open-Access Data Available

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    The Cascadia subduction zone (CSZ), where the Juan de Fuca and Gorda plates subduct obliquely beneath North America at a rate of about 35 millimeters per year, poses major geological hazards to population centers of the northwestern United States. Despite the importance of the subducting slab in these hazards, the plate boundary is poorly mapped and understood, especially offshore

    A multicenter comparison between Child Pugh and ALBI scores in patients treated with sorafenib for hepatocellular carcinoma

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    Background & aims: The ALBI grade was proposed as an objective means to evaluate liver function in patients with Hepatocellular Carcinoma (HCC). ALBI grade 1 vs 2 were proposed as stratification factors within the Child Pugh (CP) A class. However, the original publication did not provide comparison with the sub-classification by points (5 to 15) within the CP classification. Methods: We retrospectively analyzed data from patients treated with sorafenib for HCC from 17 centers in United Kingdom and France. Overall survival (OS) was analyzed with the Kaplan-Meier method and a Cox regression model. Discriminatory abilities of the classifications were assessed with the log likelihood ratio, Harrell’s C statistics and Akaike information criterion. Results: Data from 1,019 patients were collected, of which 905 could be assessed for both scores. 92% of ALBI grade 1 were CP A5 while ALBI 2 included a broad range of CP scores of which 44% were CP A6. Median OS was 10.2, 7.0 and 3.6 months for CP scores A5, A6 and >A6, respectively (P<0.001), Hazard Ratio (HR)=1.60 (95%CI: 1.35-1.89, P<0.001) for A6 vs A5. Median OS was 10.9, 6.6 and 3.0 months for ALBI grade 1, 2 and 3, respectively (P<0.001), HR=1.68 (1.43-1.97, P<0.001) for grade 2 vs 1. Discriminatory abilities of CP and ALBI were similar in the CP A population, but better for CP in the overall population. Conclusions: Our findings support the use CP class A as an inclusion criterion, and ALBI as a stratification factor in trials of systemic therapy

    What attributions do Australian high-performing general practices make for their success? Applying the clinical microsystems framework: a qualitative study

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    No commercial use is permitted unless otherwise expressly granted. This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/Objectives To identify the success attributions of high-performing Australian general practices and the enablers and barriers they envisage for practices wishing to emulate them. Design Qualitative study using semi-structured interviews and content analysis of the data. Responses were recorded, transcribed verbatim and coded according to success characteristics of high-performing clinical microsystems. Setting Primary healthcare with the participating general practices representing all Australian states and territories, and representing metropolitan and rural locations. Participants Twenty-two general practices identified as high performing via a number of success criteria. The 52 participants were 19 general practitioners, 18 practice managers and 15 practice nurses. Results Participants most frequently attributed success to the interdependence of the team members, patient-focused care and leadership of the practice. They most often signalled practice leadership, team interdependence and staff focus as enablers that other organisations would need to emulate their success. They most frequently identified barriers that might be encountered in the form of potential deficits or limitations in practice leadership, staff focus and mesosystem support. Conclusions Practice leaders need to empower their teams to take action through providing inclusive leadership that facilitates team interdependence. Mesosystem support for quality improvement in general practice should focus on enabling this leadership and team building, thereby ensuring improvement efforts are converted into effective healthcare provision.The research reported in this article was funded by a grant from the Australian Government Department of Health

    The N2K Consortium. II. A Transiting Hot Saturn Around HD 149026 With a Large Dense Core

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    Doppler measurements from Subaru and Keck have revealed radial velocity variations in the V=8.15, G0IV star HD 149026 consistent with a Saturn-Mass planet in a 2.8766 day orbit. Photometric observations at Fairborn Observatory have detected three complete transit events with depths of 0.003 mag at the predicted times of conjunction. HD 149026 is now the second brightest star with a transiting extrasolar planet. The mass of the star, based on interpolation of stellar evolutionary models, is 1.3 +/- 0.1 solar masses; together with the Doppler amplitude, K=43.3 m s^-1, we derive a planet mass Msin(i)=0.36 Mjup, and orbital radius of 0.042 AU. HD 149026 is chromospherically inactive and metal-rich with spectroscopically derived [Fe/H]=+0.36, Teff=6147 K, log g=4.26 and vsin(i)=6.0 km s^-1. Based on Teff and the stellar luminosity of 2.72 Lsun, we derive a stellar radius of 1.45 Rsun. Modeling of the three photometric transits provides an orbital inclination of 85.3 +/- 1.0 degrees and (including the uncertainty in the stellar radius) a planet radius of 0.725 +/- 0.05 Rjup. Models for this planet mass and radius suggest the presence of a ~67 Mearth core composed of elements heavier than hydrogen and helium. This substantial planet core would be difficult to construct by gravitational instability.Comment: 25 pages, 5 figures, accepted by the Astrophysical Journa

    Using statistical and artificial neural networks to predict the permeability of loosely packed granular materials

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    Well-known analytical equations for predicting permeability are generally reported to overestimate this important property of porous media. In this work, more robust models developed from statistical (multivariable regression) and Artificial Neural Network (ANN) methods utilised additional particle characteristics [‘fines ratio’ (x50/x10) and particle shape] that are not found in traditional analytical equations. Using data from experiments and literature, model performance analyses with average absolute error (AAE) showed error of ~40% for the analytical models (Kozeny–Carman and Happel–Brenner). This error reduces to 9% with ANN model. This work establishes superiority of the new models, using experiments and mathematical techniques

    Estimated incidence of previously undetected atrial fibrillation on a 14-day continuous electrocardiographic monitor and associated risk of stroke

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    Aims There is uncertainty about whether and how to perform screening for atrial fibrillation (AF). To estimate the incidence of previously undetected AF that would be captured using a continuous 14-day ECG monitor and the associated risk of stroke. Methods and results We analysed data from a cohort of patients >65 years old with hypertension and a pacemaker, but without known AF. For each participant, we simulated 1000 ECG monitors by randomly selecting 14-day windows in the 6 months following enrolment and calculated the average AF burden (total time in AF). We used Cox proportional hazards models adjusted for CHA(2)DS(2)-VASc score to estimate the risk of subsequent ischaemic stroke or systemic embolism (SSE) associated with burdens of AF > and 6 min was 3.10% (95% CI 2.53-3.72). This was consistent across strata of age and CHA(2)DS(2)-VASc scores. Over a mean follow-up of 2.4 years, the rate of SSE among patients with 6 min of AF. Conclusions Approximately 3% of individuals aged >65 years with hypertension may have more than 6 min of AF detected by a 14-day ECG monitor. This is associated with a stroke risk of over 2% per year. Whether oral anticoagulation will reduce stroke in these patients is unknown

    Involvement of right dorsolateral prefrontal cortex in ill-structured design cognition: An fMRI study

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    In ill-structured tasks, the problem to be solved is poorly specified and there is no unique correct solution. Most evidence on brain mechanisms involved in dealing with such tasks comes from neuropsychology. Here, we developed an ill-structured design task suitable for testing in a functional neuroimaging environment and compared it with a matched well-structured problem-solving task using fMRI. Consistent with prior neuropsychological results, the design task was associated with greater activity in right dorsolateral prefrontal cortex compared with problem solving. This differential activity was specific to the problem studying phase rather than performance. Furthermore, the design and problem-solving tasks differed not only in overall levels of brain activity but also in patterns of functional interactions between brain regions. These results provide new evidence on the role of right dorsolateral prefrontal cortex in ill-structured situations, such as those involved in design cognition. Additionally, these results confirm the suitability of functional neuroimaging for studying such situations

    Active surveillance to update county scale distribution of four tick species of medical and veterinary importance in Oklahoma

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    The incidence of tick-borne disease continues to increase in humans and companion animals in the United States, yet distribution maps for several tick vectors in Oklahoma, including Dermacentor variabilis, Dermacentor albipictus, Ixodes scapularis, and Amblyomma maculatum, are not available or are outdated. To address this issue, county-scale tick records from peer-reviewed literature and passive collections were reviewed for Oklahoma. Additionally, dry ice traps, tick drags, and harvested deer were utilized to actively collect adult ticks throughout the state. Through these methods, D. variabilis, D. albipictus, I. scapularis, and A. maculatum were identified in 88% (68/77), 45.4% (35/77), 66.2% (51/77), and 64.9% (50/77) of the counties in Oklahoma, respectively. Baseline maps were developed for the distribution of D. variabilis and D. albipictus and distribution maps were updated for I. scapularis and A. maculatum. This data confirms that these four species of ticks continue to be widespread within Oklahoma with a western expansion of the range of I. scapularis within the state. These results assist efforts to better understand the epidemiology of the different diseases caused by pathogens transmitted by these tick species within the Great Plains region.Peer reviewedVeterinary PathobiologyEntomology and Plant Patholog
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