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Automated Procedure (automate + procedure)
Selected AbstractsNear real-time spatial management based on habitat predictions for a longline bycatch speciesFISHERIES MANAGEMENT & ECOLOGY, Issue 6 2006A. J. HOBDAY Abstract, Southern bluefin tuna (SBT), Thunnus maccoyii (Castelnau), is a quota-managed species that makes annual winter migrations to the Tasman Sea off south-eastern Australia. During this period it interacts with a year-round tropical tuna longline fishery (Eastern Tuna and Billfish Fishery, ETBF). ETBF managers seek to minimise the bycatch of SBT by commercial ETBF longline fishers with limited or no SBT quota through spatial restrictions. Access to areas where SBT are believed to be present is restricted to fishers holding SBT quota. A temperature-based SBT habitat model was developed to provide managers with an estimate of tuna distribution upon which to base their decisions about placement of management boundaries. Adult SBT temperature preferences were determined using pop-up satellite archival tags. The near real-time predicted location of SBT was determined by matching temperature preferences to satellite sea surface temperature data and vertical temperature data from an oceanographic model. Regular reports detailing the location of temperature-based SBT habitat were produced during the period of the ETBF fishing season when interactions with SBT occur. The SBT habitat model included: (i) predictions based on the current vertical structure of the ocean; (ii) seasonally adjusted temperature preference data for the 60 calendar days centred on the prediction date; and (iii) development of a temperature-based SBT habitat climatology that allowed visualisation of the expected change in the distribution of the SBT habitat zones throughout the season. At the conclusion of the fishing season an automated method for placing management boundaries was compared with the subjective approach used by managers. Applying this automated procedure to the habitat predictions enabled an investigation of the effects of setting management boundaries using old data and updating management boundaries infrequently. Direct comparison with the management boundaries allowed an evaluation of the efficiency and biases produced by this aspect of the fishery management process. Near real-time fishery management continues to be a realistic prospect that new scientific approaches using novel tools can support and advance. [source] Solving crystal structures in P1: an automated procedure for finding an allowed origin in the correct space groupJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 2 2000Maria Cristina Burla Crystal structure solution in P1 may be particularly suitable for complex crystal structures crystallizing in other space groups. However, additional efforts and human intervention are often necessary to locate correctly the structural model so obtained with respect to an allowed origin of the actual space group. An automatic procedure is described which is able to perform such a task, allowing the routine passage to the correct space group and the subsequent structure refinement. Some tests are presented proving the effectiveness of the procedure. [source] Poster Sessions AP13: Novel Techniques and TechnologiesJOURNAL OF NEUROCHEMISTRY, Issue 2002J. K. Yao Studies of the antioxidant defense system and the monoamine metabolic pathways are often complicated by cumbersome analytical methods, which require separate and multistep extraction and chemical reaction procedures. Thus, measurements of multiple parameters are limited in relatively small biological samples. High performance liquid chromatography (HPLC) coupled with a Coulometric Multi-Electrode Array System (CMEAS) provides us a convenient and most sensitive tool to measure low molecular weight, redox-active compounds in biological sample. The deproteinized sample was analyzed on a HPLC coupled with a 16-channel CMEAS, which incremented from 60 to 960 mV in 60 mV steps. Each sample was run on a single column (Meta-250, 4.6 × 250 mm) under a 150-minute complex gradient that ranged from 0% B (A: 1.1% pentane sulfonic acid) to 20% B (B: 0.1 m lithium acetate in mixture of methanol, acetonenitrile and isopropanol), with a flow rate of 0.5 mL/min. We have developed an automated procedure to simultaneously measure various antioxidant, oxidative stress marker, and monoamine metabolites in a single column with binary gradient. No other chemical reactions are necessary. In order to reduce the running time and yet achieve a reproducible retention time by the autosampler injection, our gradient elution profile was modified to produce a shorter equilibration time and to compensate for the initial contamination of mobile phase B following the first injection. Without the use of two columns in series and peak suppresser/gradient mixer, we have simplified the previously published method to measure over 20 different antioxidants, oxidative stress markers and monoamine metabolites simultaneously in biological samples. [source] Diffraction-based automated crystal centeringJOURNAL OF SYNCHROTRON RADIATION, Issue 2 2007Jinhu Song A fully automated procedure for detecting and centering protein crystals in the X-ray beam of a macromolecular crystallography beamline has been developed. A cryo-loop centering routine that analyzes video images with an edge detection algorithm is first used to determine the dimensions of the loop holding the sample; then low-dose X-rays are used to record diffraction images in a grid over the edge and face plane of the loop. A three-dimensional profile of the crystal based on the number of diffraction spots in each image is constructed. The derived center of mass is then used to align the crystal to the X-ray beam. Typical samples can be accurately aligned in ,2,3,min. Because the procedure is based on the number of `good' spots as determined by the program Spotfinder, the best diffracting part of the crystal is aligned to the X-ray beam. [source] Validity of Ellenberg indicator values judged from physico-chemical field measurementsJOURNAL OF VEGETATION SCIENCE, Issue 2 2002G.W.W. Wamelink Abstract. The relationship between mean Ellenberg indicator values (IV) per vegetation relevé and environmental parameters measured in the field usually shows a large variation. We tested the hypothesis that this variation is caused by bias dependent on the phytosociological class. For this purpose we collected data containing vegetation relevés and measured soil pH (3631 records) or mean spring groundwater level (MSL, 1600 records). The relevés were assigned to vegetation types by an automated procedure. Regression of the mean indicator values for acidity on soil pH and the mean indicator values for moisture on MSL gave percentages explained variance similar to values that were reported earlier in literature. When the phytosociological class was added as an explanatory factor the explained variance increased considerably. Regression lines per vegetation type were estimated, many of which were significantly different from each other. In most cases the intercepts were different, but in some cases their slopes differed as well. The results show that Ellenberg indicator values for acidity and moisture appear to be biased towards the values that experts expect for the various phytosociological classes. On the basis of the results, we advise to use Ellenberg IVs only for comparison within the same vegetation type. [source] HPLC,SPE,NMR hyphenation in natural products research: optimization of analysis of Croton membranaceus extract,MAGNETIC RESONANCE IN CHEMISTRY, Issue 9 2005Maja Lambert Abstract The HPLC,SPE,NMR technique was used for the analysis of a root-bark extract of Croton membranaceus. The components of the extract were separated on an analytical-size reversed-phase HPLC column, the chromatographic peaks were trapped on SPE (solid-phase extraction) cartridges after post-column dilution of the eluate with water and the compounds were eluted from the cartridges with acetonitrile- d3 into a 30 µl 600 MHz NMR probe in a fully automated procedure. The trapping efficiency of scopoletin (1), the major extract constituent, was much higher on a GP (general phase, a polystyrene-type polymer) SPE phase than on a C18 phase. Thus, under the conditions used, up to 100 µg of scopoletin per cartridge could be accumulated linearly after repeated trappings. The maximum achievable NMR signal-to-noise ratio using the GP cartridges was at least four times higher than that achievable with the C18 cartridges. It was shown that excessively long T1 relaxation times may compromise experiments in which acetonitrile- d3 is used as the cartridge eluent. Nevertheless, the sensitivity gain provided by the HPLC,SPE,NMR technique through repeated peak trappings allowed the acquisition of good-quality proton-detected 2D NMR spectra without the need for solvent suppression. Copyright © 2005 John Wiley & Sons, Ltd. [source] A METHOD FOR SIMPLIFYING LARGE ECOSYSTEM MODELSNATURAL RESOURCE MODELING, Issue 2 2008JOCK LAWRIE Abstract Simplifying large ecosystem models is essential if we are to understand the underlying causes of observed behaviors. However, such understanding is often employed to achieve simplification. This paper introduces two model simplification methods that can be applied without requiring intimate prior knowledge of the system. Their utility is measured by the resulting values of given model diagnostics relative to those of the large model. The first method is a simple automated procedure for nondimensionalizing large ecosystem models, which identifies and eliminates terms that have little effect on model diagnostics. Some of its limitations are then addressed by the rate elimination method, which measures the relative importance of model terms using least-squares regression. The methods are applied to a model of the nitrogen cycle in Port Phillip Bay, Victoria, Australia. The rate elimination method provided more insights into the causal relationships built into the model than the nondimensionalizing method. It also allowed the reduction of the model's dimension. Thus it is a useful first step in model simplification. [source] Performance of an Autonomous Telemonitoring System in Children and Young Adults with Congenital Heart DiseasesPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2008PETER ZARTNER M.D. Background:Integrated telemonitoring systems controlling circulatory and electrical parameters in adults with an implanted pacemaker have shown to be advantageous during follow-up of this patient group. In children and young adults with a congenital heart disease (CHD), these systems have to cope with a diversity of varying arrhythmias and a broad range of intrinsic cardiac parameters. Additional problems arise from the patients' growth and anatomic anomalies. Methods:Since 2005, eight young patients (age 4.1, 37 years, mean 15.5 years) with a CHD received a pacemaker or implantable cardioverter defibrillator with an autonomous telemonitoring system at our clinic. The mean follow-up time was 395 days (range 106,834 days, 8.7 patient years). Results:In seven of eight patients the system transmitted information, which led to beneficial modifications of the current antiarrhythmic therapy. In three patients the reported events were of a critical nature. One patient remained event-free for 192 days after implantation. During follow-up, 96% of the days were covered. The system also transferred additional information on the effectiveness of antiarrhythmic medication and the impact of physical activity. Conclusions:Young patients with an insufficient intrinsic heart rate or progressing arrhythmia, in addition to the conventional indications for pacemaker or defibrillator implantation, seem to profit to a high percentage from a telemetric surveillance system. The fully automated procedure of device interrogation and information transmission gives a daily overview on system function and specific arrhythmic events, especially in children who are unaware of any symptoms. [source] Application of tandem mass spectrometry combined with gas chromatography and headspace solid-phase dynamic extraction for the determination of drugs of abuse in hair samplesRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 5 2003Dirk W. Lachenmeier A new method combination, headspace solid-phase dynamic extraction coupled with gas chromatography/tandem mass spectrometry (HS-SPDE/GC/MS/MS), is introduced to determine drugs of abuse in hair samples. This highly automated procedure utilizes SPDE for pre-concentration and on-coating derivatization as well as GC and triple quadrupole MS/MS for selective and sensitive detection. All these steps, apart from washing and cutting of the hair samples, are performed without manual intervention on a robot-like autosampler. SPDE is a solventless extraction technique related to solid-phase microextraction (SPME). The analytes are absorbed from the sample headspace directly into a hollow needle with an internal coating of polydimethylsiloxane by repeated aspirate/dispense cycles. The HS-SPDE/GC/MS/MS procedure was applied to the analysis of methadone, the trimethylsilyl derivatives of cannabinoids and the trifluoroacetyl derivatives of amphetamines and designer drugs. The method was shown to be sensitive with detection limits between 6 and 52 pg/mg hair matrix and precision between 0.4 and 7.8% by the use of an internal standard technique. Linearity was obtained from 0.1,20,ng/mg with coefficients of correlation between 0.995 and 0.999. Compared with conventional methods of hair analysis, HS-SPDE/GC/MS/MS is easier to use, substantially faster, with the degree of sensitivity and reproducibility demanded in clinical and forensic toxicology. The main advantage of the SPDE technique in relation to SPME is the robustness of the capillary. Copyright © 2003 John Wiley & Sons, Ltd. [source] Simultaneous Factor Selection and Collapsing Levels in ANOVABIOMETRICS, Issue 1 2009Howard D. Bondell Summary When performing an analysis of variance, the investigator often has two main goals: to determine which of the factors have a significant effect on the response, and to detect differences among the levels of the significant factors. Level comparisons are done via a post-hoc analysis based on pairwise differences. This article proposes a novel constrained regression approach to simultaneously accomplish both goals via shrinkage within a single automated procedure. The form of this shrinkage has the ability to collapse levels within a factor by setting their effects to be equal, while also achieving factor selection by zeroing out entire factors. Using this approach also leads to the identification of a structure within each factor, as levels can be automatically collapsed to form groups. In contrast to the traditional pairwise comparison methods, these groups are necessarily nonoverlapping so that the results are interpretable in terms of distinct subsets of levels. The proposed procedure is shown to have the oracle property in that asymptotically it performs as well as if the exact structure were known beforehand. A simulation and real data examples show the strong performance of the method. [source] The influence of elevation error on the morphometrics of channel networks extracted from DEMs and the implications for hydrological modellingHYDROLOGICAL PROCESSES, Issue 11 2008John B. Lindsay Abstract Stream network morphometrics have been used frequently in environmental applications and are embedded in several hydrological models. This is because channel network geometry partly controls the runoff response of a basin. Network indices are often measured from channels that are mapped from digital elevation models (DEMs) using automated procedures. Simulations were used in this paper to study the influence of elevation error on the reliability of estimates of several common morphometrics, including stream order, the bifurcation, length, area and slope ratios, stream magnitude, network diameter, the flood magnitude and timing parameters of the geomorphological instantaneous unit hydrograph (GIUH) and the network width function. DEMs of three UK basins, ranging from high to low relief, were used for the analyses. The findings showed that moderate elevation error (RMSE of 1·8 m) can result in significant uncertainty in DEM-mapped network morphometrics and that this uncertainty can be expressed in complex ways. For example, estimates of the bifurcation, length and area ratios and the flood magnitude and timing parameters of the GIUH each displayed multimodal frequency distributions, i.e. two or more estimated values were highly likely. Furthermore, these preferential estimates were wide ranging relative to the ranges typically observed for these indices. The wide-ranging estimates of the two GIUH parameters represented significant uncertainty in the shape of the unit hydrograph. Stream magnitude, network diameter and the network width function were found to be highly sensitive to elevation error because of the difficulty in mapping low-magnitude links. Uncertainties in the width function were found to increase with distance from outlet, implying that hydrological models that use network width contain greater uncertainty in the shape of the falling limb of the hydrograph. In light of these findings, care should be exercised when interpreting the results of analyses based on DEM-mapped stream networks. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||||||||