253 research outputs found

    QXLA: Adding Upper Quantiles for the Studentized Range to Excel for Multiple Comparison Procedures

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    Microsoft Excel has some functionality in terms of basic statistics; however it lacks distribution functions built around the studentized range (Q). The developed Excel addin introduces two new user-defined functions, QDISTG and QINVG, based on the studentized range Q-distribution that expands the functionality of Excel for statistical analysis. A workbook example, demonstrating the Tukey, S-N-K, and REGWQ tests, has also been included. Compared with other options available, the method is fast with low error rates

    Computer Model for Prediction of PCB Dechlorination and Biodegradation Endpoints,”

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    Mathematical modeling of polychlorinated biphenyl (PCB) transformation served as a means of predicting possible endpoints of bioremediation, thus allowing evaluation of several of the most common transformation patterns. Correlation between laboratory-observed and predicted endpoint data was, in some cases, as good as 0.98 (perfect correlation = 1.0)

    Bio-Energy Production from Anaerobic Digestion of Animal and Farm Wastes

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    Track II: Transportation and BiofuelsIncludes audio file (20 min.)US produces annually huge amount of animal and farm wastes (e.g. only cow manure in amount of about 1.8 billion tons). These wastes can be valuable source of renewable energy besides overcoming the environmental problems caused by them such as greenhouse gas effect of methane emission of 22 times worse than carbon dioxide, surface and ground water contamination, odor, dust, ammonia leaching, etc. In this project we systematically studied the process, kinetics, microorganisms interaction and population, and the effects of design and operating parameters on reactor design and scale up of cow manure digestion for bioenergy production and for wastes treatment by developing and implementing advanced imaging, visualization and computational techniques such as computational fluid dynamics (CFD), novel multiple radioactive particles tracking technique (MRPT), novel dual source computed tomography (DSCT), and microbiology imaging techniques. New design and conditions of anaerobic digesters that can reduce significantly the inactive volume and improve the digesters performance have been identified and recommended. In addition, for the first time, the energy produced has been related to the energy introduced in order to maximize the energy output while minimizing the energy input through the mixing power consumed. It is hoped that the findings will be applied in the field to promote bioenergy production and eliminate major environmental pollution problems

    Methane Production in a 100-L Upflow Bioreactor by Anaerobic Digestion of Farm Waste

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    Manure Waste from Dairy Farms Has Been Used for Methane Production for Decades, However, Problems Such as Digester Failure Are Routine. the Problem Has Been Investigated in Small Scale (1-2 L) Digesters in the Laboratory; However, Very Little Scale-Up to Intermediate Scales Are Available. We Report Production of Methane in a 100-L Digester and the Results of an Investigation into the Effect of Partial Mixing Induced by Gas Upflow/recirculation in the Digester. the Digester Was Operated for a Period of About 70 D (With 16-D Hydraulic Retention Time) with and Without the Mixing Induced by Gas Recirculation through an Internal Draft Tube. the Results Show a Clear Effect of Mixing on Digester Operation. Without Any Mixing, the Digester Performance Deteriorated within 30-50 D, Whereas with Mixing Continuous Production of Methane Was Observed. This Study Demonstrates the Importance of Mixing and its Critical Role in Design of Large-Scale Anaerobic Digesters. Copyright © 2006 by Humana Press Inc. All Rights of Any Nature Whatsoever Reserved

    Mesophilic Digestion Kinetics of Manure Slurry

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    Anaerobic Digestion Kinetics Study of Cow Manure Was Performed at 35°C in Bench-Scale Gas-Lift Digesters (3.78 L Working Volume) at Eight Different Volatile Solids (VS) Loading Rates in the Range of 1.11-5.87 G L-1 Day-1. the Digesters Produced Methane at the Rates of 0.44-1.18 L L-1 Day-1, and the Methane Content of the Biogas Was Found to Increase with Longer Hydraulic Retention Time (HRT). based on the Experimental Observations, the Ultimate Methane Yield and the Specific Methane Productivity Were Estimated to Be 0.42 L CH4 (G vs. Loaded)-1 and 0.45 L CH4 (G vs. Consumed)-1, Respectively. Total and Dissolved Chemical Oxygen Demand (COD) Consumptions Were Calculated to Be 59-17% and 78-43% at 24.4-4.6 Days HRTs, respectively. Maximum Concentration of Volatile Fatty Acids in the Effluent Was Observed as 0.7 G L-1 at 4.6 Days HRT, While It Was Below Detection Limit at HRTs Longer Than 11 Days. the Observed Methane Production Rate Did Not Compare Well with the Predictions of Chen and Hashimoto\u27s [1] and Hill\u27s [2] Models using their Recommended Kinetic Parameters. However, under the Studied Experimental Conditions, the Predictions of Chen and Hashimoto\u27s [1] Model Compared Better to the Observed Data Than that of Hill\u27s [2] Model. the Nonlinear Regression Analysis of the Experimental Data Was Performed using a Derived Methane Production Rate Model, for a Completely Mixed Anaerobic Digester, Involving Contois Kinetics [3] with Endogenous Decay. the Best Fit Values for the Maximum Specific Growth Rate (Μm) and Dimensionless Kinetic Parameter (K) Were Estimated as 0.43 Day-1 and 0.89, Respectively. the Experimental Data Were Found to Be within 95% Confidence Interval of the Prediction of the Derived Methane Production Rate Model with the Sum of Residual Squared Error as 0.02. © Humana Press Inc. 2007

    Circulating neurofilament light in ischemic stroke: temporal profile and outcome prediction

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    BACKGROUND AND PURPOSE: Neurofilament light chain (NfL) is a marker of neuroaxonal damage. We aimed to study associations between serum NfL (sNfL) concentrations at different time points after ischemic stroke and outcomes. // METHODS: We prospectively included ischemic stroke cases (n = 595, mean age 59 years, 64% males) and assessed outcomes by both the modified Rankin Scale (mRS) and the NIH stroke scale (NIHSS) at 3 months and by mRS at 2 years. In a subsample, long-term (7-year) outcomes were also assessed by both mRS and NIHSS. We used the ultrasensitive single-molecule array assay to measure sNfL in the acute phase (range 1-14, median 4 days), after 3 months and 7 years in cases and once in controls (n = 595). // RESULTS: Acute-phase sNfL increased by the time to blood-draw and highest concentrations were observed at 3 months post-stroke. High sNfL associated to stroke severity and poor outcomes, and both associations were strongest for 3-month sNfL. After adjusting for age, previous stroke, stroke severity, and day of blood draw, 3-month sNfL was significantly associated to both outcomes at all time points (p < 0.01 throughout). For all main etiological subtypes, both acute phase and 3-month sNfL were significantly higher than in controls, but the dynamics of sNfL differed by stroke subtype. // CONCLUSIONS: The results from this study inform on sNfL in ischemic stroke and subtypes over time, and show that sNfL predicts short- and long-term neurological and functional outcomes. Our findings suggest a potential utility of sNfL in ischemic stroke outcome prediction
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