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Available Instruments (available + instruments)
Selected AbstractsClinical features and assessment of severe dementia.EUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2002A review Sound understanding of the dementia syndrome requires adequate acquaintance with its entire spectrum, from the lightest to the most advanced stages. Most studies of dementia deal with light to moderate stages of the condition, while relatively little attention has been paid to its most severe stages. This review presents a clinical description of patients with severe dementia and of the tests currently available to evaluate their cognitive, behavioural, and functional status. Available instruments such as the Hierarchic Dementia Scale or the Severe Impairment Battery now allow quantification of the cognitive and behavioural status of patients with severe dementia. Experience with severe dementia shows that, far from being in a `vegetative state', as is commonly thought, late-stage patients are in fact quite different from one another and in most cases continue to have an interaction with their environment. This ability to better define the characteristics of patients with severe dementia provides the basis for correlations between clinical data and data derived from neuroimaging, neurochemistry, or neuropathology. It also sets the stage for possible therapeutic trials involving these patients. [source] Acute-care nurses' attitudes towards older patients: A literature reviewINTERNATIONAL JOURNAL OF NURSING PRACTICE, Issue 2 2000Mary Courtney PhD With increases in life expectancy and increasing numbers of older patients utilising the acute setting, attitudes of registered nurses caring for older people may affect the quality of care provided. This paper reviews recent research on positive and negative attitudes of acute-care nurses towards older people. Many negative attitudes reflect ageist stereotypes and knowledge deficits that significantly influence registered nurses' practice and older patients' quality of care. In the acute setting, older patients experience reduced independence, limited decision-making opportunities, increased probability of developing complications, little consideration of their ageing-related needs, limited health education and social isolation. Available instruments to measure attitudes towards and knowledge about older people, although reliable and valid, are outdated, country-specific and do not include either a patient focus or a caring perspective. This paper argues for the development and utilisation of a research instrument that includes both a patient focus and a caring dimension. [source] Measurement and data analysis methods for field-scale wind erosion studies and model validation,EARTH SURFACE PROCESSES AND LANDFORMS, Issue 11 2003Ted M. Zobeck Abstract Accurate and reliable methods of measuring windblown sediment are needed to con,rm, validate, and improve erosion models, assess the intensity of aeolian processes and related damage, determine the source of pollutants, and for other applications. This paper outlines important principles to consider in conducting ,eld-scale wind erosion studies and proposes strategies of ,eld data collection for use in model validation and development. Detailed discussions include consideration of ,eld characteristics, sediment sampling, and meteorological stations. The ,eld shape used in ,eld-scale wind erosion research is generally a matter of preference and in many studies may not have practical signi,cance. Maintaining a clear non-erodible boundary is necessary to accurately determine erosion fetch distance. A ,eld length of about 300 m may be needed in many situations to approach transport capacity for saltation ,ux in bare agricultural ,elds. Field surface conditions affect the wind pro,le and other processes such as sediment emission, transport, and deposition and soil erodibility. Knowledge of the temporal variation in surface conditions is necessary to understand aeolian processes. Temporal soil properties that impact aeolian processes include surface roughness, dry aggregate size distribution, dry aggregate stability, and crust characteristics. Use of a portable 2 tall anemometer tower should be considered to quantify variability of friction velocity and aerodynamic roughness caused by surface conditions in ,eld-scale studies. The types of samplers used for sampling aeolian sediment will vary depending upon the type of sediment to be measured. The Big Spring Number Eight (BSNE) and Modi,ed Wilson and Cooke (MWAC) samplers appear to be the most popular for ,eld studies of saltation. Suspension ,ux may be measured with commercially available instruments after modi,cations are made to ensure isokinetic conditions at high wind speeds. Meteorological measurements should include wind speed and direction, air temperature, solar radiation, relative humidity, rain amount, soil temperature and moisture. Careful consideration of the climatic, sediment, and soil surface characteristics observed in future ,eld-scale wind erosion studies will ensure maximum use of the data collected. Copyright © 2003 John Wiley & Sons, Ltd. [source] Contactless Conductivity Detection in Capillary Electrophoresis: A ReviewELECTROANALYSIS, Issue 24 2004Pavel Kubá Abstract The popularity of contactless conductivity detection in capillary electrophoresis has been growing steadily over the last few years. Improvements have been made in the design of the detector in order to facilitate its handling, to allow easy incorporation into available instruments or to achieve higher sensitivity. The understanding of its fundamental working principles has been advanced and the detection approach has also been transferred to lab-on-chip devices. The range of applications has been extended greatly from the initial work on small inorganic ions to include organic species and biomolecules. Concurrent determination of cations and anions by dual injection from opposite ends has been demonstrated as well as sample introduction by using flow-injection systems for easy automation of the process. [source] Improved automated extraction and separation procedure for soil lipid analysesEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 2 2004G. L. B. Wiesenberg Summary Analysis of soil lipids may contribute to an improved understanding of atmosphere to soil carbon fluxes, soil organic matter source differentiation and pollutant accumulation. Soil lipids, mostly originating from plants and microorganisms, have traditionally been analysed by non-automated extraction and separation methods, which produce several lipid fractions, operationally defined by polarity. Here we present a combination of fast, automated and reproducible techniques, adopted from organic geochemical studies, for preparative separation of individual soil lipid fractions with increasing polarity. These techniques involve commercially available instruments, including accelerated solvent extraction and a two-step automated medium-pressure liquid chromatography procedure. The method yields eight lipid fractions consisting of five fractions fully amenable to gas chromatography/mass spectrometry (GC/MS) (aliphatic hydrocarbons, aromatic hydrocarbons, ketones, alcohols, carboxylic acids), and three fractions of highly polar or high molecular weight compounds (bases, very long-chain wax esters (C40+), high polarity compounds) that were not measurable with GC/MS under standard conditions. We tested the method on five agricultural soils. Results show that (i) mass recoveries for the individual fractions are reproducible, (ii) within individual fractions compound distribution patterns are reproducible, as demonstrated for alkanes and carboxylic acids, and (iii) individual fractions represent distinct and clean compound classes, free of interfering substances detectable by GC/MS. Thus, automated separation can be a fast, effective and reproducible procedure for fractionation of complex mixtures of soil lipids into clean compound classes, directly suitable for a variety of molecular (e.g. GC/MS) and isotopic characterizations (e.g. gas chromatography coupled with isotope ratio monitoring mass spectrometry or accelerator mass spectrometry). [source] A quick, practical test procedure to evaluate the performance of instruments used for in vitro UV protection measurementsINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2002E. Klette Synopsis The in vitro determination of the UV protection of sunscreens is usually performed by means of transmission measurements with special photometers. Many different instruments are used. Besides numerous commercially available instruments, which are equipped by the manufacturer for the specific measurement, other modular instruments are used. We present here a quick and practical method to evaluate the performance of these instruments with respect to their measuring ranges and to compare the uniformity and reliability of the results obtained with these instruments. Résumé La détermination in vitro de la protection anti-UV de produits solaires est généralement réalisée par la mesure de la transmission à l'aide de photomètres spéciaux. De nombreux appareils peuvent être utilisés à cette fin. A côté des instruments disponibles dans le commerce et spécialement équipés par les fabricants, d'autres appareils modulaires peuvent être employés. Nous présentons ici une méthode rapide et pratique pour évaluer les performances de ces appareils en respectant leurs gammes de mesure et pour comparer la crédibilité et l'uniformité des résultats obtenus. [source] Inkjet Printing of Polymer Micro-Arrays and Libraries: Instrumentation, Requirements, and PerspectivesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 11 2003Berend-Jan de Gans Abstract This article reviews commercially available instrumentation for inkjet printing of polymer micro-arrays for combinatorial materials research, and requirements thereof. These include a print head positioning accuracy better than 10 ,m and a minimum drop volume of 100 pL. Commercially available instruments that fulfill these requirements can be divided into two categories, depending on whether they receive ink from a reservoir (dispense mode) or through fluid aspiration (pipette mode). Instruments belonging to the first category are restricted to the preparation of polymer blend micro-arrays. These consist of a few substances mixed in various ratios. The other instruments can be used for the preparation of both micro-arrays of large numbers of different pure polymer compounds and polymer blend micro-arrays. Moreover, ways to mix compounds are discussed. [source] A predictive high-throughput scale-down model of monoclonal antibody production in CHO cellsBIOTECHNOLOGY & BIOENGINEERING, Issue 6 2009Rachel Legmann Abstract Multi-factorial experimentation is essential in understanding the link between mammalian cell culture conditions and the glycoprotein product of any biomanufacturing process. This understanding is increasingly demanded as bioprocess development is influenced by the Quality by Design paradigm. We have developed a system that allows hundreds of micro-bioreactors to be run in parallel under controlled conditions, enabling factorial experiments of much larger scope than is possible with traditional systems. A high-throughput analytics workflow was also developed using commercially available instruments to obtain product quality information for each cell culture condition. The micro-bioreactor system was tested by executing a factorial experiment varying four process parameters: pH, dissolved oxygen, feed supplement rate, and reduced glutathione level. A total of 180 micro-bioreactors were run for 2 weeks during this DOE experiment to assess this scaled down micro-bioreactor system as a high-throughput tool for process development. Online measurements of pH, dissolved oxygen, and optical density were complemented by offline measurements of glucose, viability, titer, and product quality. Model accuracy was assessed by regressing the micro-bioreactor results with those obtained in conventional 3,L bioreactors. Excellent agreement was observed between the micro-bioreactor and the bench-top bioreactor. The micro-bioreactor results were further analyzed to link parameter manipulations to process outcomes via leverage plots, and to examine the interactions between process parameters. The results show that feed supplement rate has a significant effect (P,<,0.05) on all performance metrics with higher feed rates resulting in greater cell mass and product titer. Culture pH impacted terminal integrated viable cell concentration, titer and intact immunoglobulin G titer, with better results obtained at the lower pH set point. The results demonstrate that a micro-scale system can be an excellent model of larger scale systems, while providing data sets broader and deeper than are available by traditional methods. Biotechnol. Bioeng. 2009; 104: 1107,1120. © 2009 Wiley Periodicals, Inc. [source] A Mass Spectrometry Plate Reader: Monitoring Enzyme Activity and Inhibition with a Desorption/Ionization on Silicon (DIOS) PlatformCHEMBIOCHEM, Issue 7 2004Zhouxin Shen Dr. Abstract A surface-based laser desorption/ionization mass spectrometry assay that makes use of Desorption/Ionization on Silicon Mass Spectrometry (DIOS-MS) has been developed to monitor enzyme activity and enzyme inhibition. DIOS-MS has been used to characterize inhibitors from a library and then to monitor their activity against selected enzyme targets, including proteases, glycotransferase, and acetylcholinesterase. An automated DIOS-MS system was also used as a high-throughput screen for the activity of novel enzymes and enzyme inhibitors. On two different commercially available instruments, a sampling rate of up to 38 inhibitors per minute was accomplished, with thousands of inhibitors being monitored. The ease of applying mass spectrometry toward developing enzyme assays and the speed of surface-based assays such as DIOS for monitoring inhibitor effectiveness and enzyme activity makes it attractive for a broad range of screening applications. [source] | ||||||||||||||||