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Parallel Measurement (parallel + measurement)
Selected AbstractsLow-intensity microwave irradiation does not substantially alter gene expression in late larval and adult Caenorhabditis elegansBIOELECTROMAGNETICS, Issue 8 2009Adam S. Dawe Abstract Reports that low-intensity microwave radiation induces heat-shock reporter gene expression in the nematode, Caenorhabditis elegans, have recently been reinterpreted as a subtle thermal effect caused by slight heating. This study used a microwave exposure system (1.0,GHz, 0.5,W power input; SAR 0.9,3,mW,kg,1 for 6-well plates) that minimises temperature differentials between sham and exposed conditions (,0.1 °C). Parallel measurement and simulation studies of SAR distribution within this exposure system are presented. We compared five Affymetrix gene arrays of pooled triplicate RNA populations from sham-exposed L4/adult worms against five gene arrays of pooled RNA from microwave-exposed worms (taken from the same source population in each run). No genes showed consistent expression changes across all five comparisons, and all expression changes appeared modest after normalisation (,40% up- or down-regulated). The number of statistically significant differences in gene expression (846) was less than the false-positive rate expected by chance (1131). We conclude that the pattern of gene expression in L4/adult C. elegans is substantially unaffected by low-intensity microwave radiation; the minor changes observed in this study could well be false positives. As a positive control, we compared RNA samples from N2 worms subjected to a mild heat-shock treatment (30 °C) against controls at 26 °C (two gene arrays per condition). As expected, heat-shock genes are strongly up-regulated at 30 °C, particularly an hsp -70 family member (C12C8.1) and hsp -16.2. Under these heat-shock conditions, we confirmed that an hsp -16.2::GFP transgene was strongly up-regulated, whereas two non-heat-inducible transgenes (daf- 16::GFP; cyp -34A9::GFP) showed little change in expression. Bioelectromagnetics 30:602,612, 2009. © 2009 Wiley-Liss, Inc. [source] Limitations to CO2 assimilation in ozone-exposed leaves of Plantago majorNEW PHYTOLOGIST, Issue 1 2002Y. Zheng Summary ,,The potential limitations on net leaf carbon assimilation imposed by stomatal conductance, carboxylation velocity, capacity for ribulose 1,5-bisphosphate regeneration and triose phosphate ultilization rate were derived from steady-state gas exchange measurements made over the life-span of two leaves on plants of an ,O3 -sensitive' population of Plantago major grown at contrasting atmospheric O3 concentrations. ,,Parallel measurements of chlorophyll fluorescence were used to monitor changes in the quantum efficiency of PSII photochemistry, and in vitro measurements of Rubisco activity were made to corroborate modelled gas exchange data. ,,Data indicated that a loss of Rubisco was predominantly responsible for the decline in CO2 assimilation observed in O3 -treated leaves. The quantum efficiency of PSII was unchanged by O3 exposure. ,,Stomatal aperture declined in parallel with CO2 assimilation in O3 -treated plants, but this did not account for the observed decline in photosynthesis. Findings suggested that O3 -induced shifts in stomatal conductance result from ,direct' effects on the stomatal complex as well as ,indirect effects' mediated through changes in intercellular CO2 concentration. Leaves on the same plant exposed to equivalent levels of O3 showed striking differences in their response to the pollutant. [source] Long-term outcomes after a structured hypertension education programme for patients with diabetes and hypertensionEUROPEAN DIABETES NURSING, Issue 2 2005B Osterbrink Nurse Teacher, Diabetes Counsellor, Principal of the Academy of Health Professions Abstract A structured hypertension treatment and education programme (HTEP) was developed in the Düsseldorf area in the 1990s for patients with diabetes mellitus and hypertension and was found to be effective in a randomised controlled trial. The German Association of Diabetes Education and Counselling Professions (VDBD) implemented the HTEP all over Germany in order to optimise the care of patients with diabetes and hypertension. The objectives of the HTEP are to enable patients to gain knowledge of hypertension, to participate actively in their treatment to improve blood pressure (BP) and metabolic control and to self-measure their BP. The implementation consisted of two stages. The first stage comprised the training of 312 diabetes counsellors (DCs). During the second stage 473 patients with type 1 or type 2 diabetes and hypertension in 35 diabetes centres throughout Germany received the HTEP including instructions in BP self-measurement. The HTEP consists of four units each one with a duration of 90 minutes covering the topics: hypertension, BP self-monitoring according to the standards of the German Hypertension League, antihypertensive medication including effects and side effects, recommendations to moderate exercise, weight reduction, dietary advice with reference to reduction of salt and alcohol and normalising the intake of protein. These patients participated in a prospective non-experimental study with a follow up of three years investigating the long-term outcomes of the HTEP in uncontrolled settings. The DCs assessed the accuracy of patients' self-monitoring by parallel measurement. Assessments included questionnaires evaluating patients' understanding of hypertension and metabolic control. The mean BP monitored by the DC fell from 150/85mmHg to 147/80mmHg (p<0.0001). The accuracy of self-measurements increased from 76% to 86% (p<0.005) and mean self-measurement readings decreased from 142/81mmHg to 139/78mmHg. HbA1c fell significantly from 7.9±1.6% to 7.3±1.1% (mean ± SD, p<0.001) and total cholesterol was lowered from 241±67.1mg/dl to 200±40.4mg/dl (p<0.001). Patients' knowledge of hypertension increased from 62% before the intervention to 72% after three years' follow up. Patients over 70 years showed less knowledge than younger patients (p<0.005). It was concluded that the HTEP is effective in improving BP, metabolic control and knowledge of hypertension. It enables patients to measure their BP precisely and regularly. Copyright © 2005 FEND. [source] Eignung eines großen Flüssigkeits- und eines Luftpyknometers zur Bestimmung des Rohvolumens von Feststoffen unterschiedlicher Art und GrößeJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 2 2005Berthold Deller Abstract Das Feststoffvolumen von Materialien, die sowohl relativ große als auch spezifisch leichte Bestandteile enthalten, kann nach DIN ISO 11508 (mit relativ kleinen Flüssigkeitspyknometern (FP) und submerser Wägung in Wasser) nicht bestimmt werden. Deshalb wurde geprüft, ob es ohne Zerkleinerung des Untersuchungsmaterials in einem größeren FP (ca. 280,cm3) oder einem Luftpyknometer (LP) genau genug zu ermitteln ist. Materialien mit gröberen Bestandteilen bzw. Feststoffe mit sehr unterschiedlicher Rohdichte ergaben mit dem FP größere Differenzen zwischen Parallelansätzen als die wiederholte Befüllung mit Wasser und die Untersuchung von feinkörnigen Mineralböden erwarten ließ. Die wesentliche Ursache dafür wird in der materialspezifischen Inhomogenität gesehen. Das FP scheint somit für die Untersuchung von Materialien mit Partikeldurchmessern von bis zu 3,cm grundsätzlich geeignet. Die Bestimmung muss jedoch jeweils an mindestens zwei Parallelproben erfolgen und ggf. erweitert werden, um verlässliche Mittelwerte zu erhalten. Die gleiche Bestimmung mit einem selbst gebauten LP ergab zu niedrige Werte für das Rohvolumen, wenn die Materialien ofentrocken, lufttrocken und feucht waren (Ausnahme: solche mit kompakten und relativ großen Partikeln). Die Fehler traten sowohl bei der Messung durch Luftdrucksenkung (ca. ,300 hPa) als auch unter Druckerhöhung (ca. 100,hPa) auf. Das Volumen von reinem Wasser konnte demgegenüber unter Druckerhöhung wesentlich genauer und richtiger bestimmt werden. Nach Kochen der Proben (wie für die Flüssigkeitspyknometrie) und Überdecken mit Wasser in der LP-Messkammer waren die Ergebnisse deutlich besser mit denen des FP vergleichbar und plausibler. Die Fehlerursachen werden darin gesehen, dass die Messung durch adsorbierte Luft (getrocknete und lufttrockene Proben) gestört wird bzw. Wasser von den Materialoberflächen während des Messvorganges verdampft. Suitability of a large liquid pycnometer and an air pycnometer to determine the raw volume of solids of different type and size The raw volume of materials, which contain constituents of relatively large size as well as of low density, can not be determined according to ISO 11508 without grinding. Therefore, this study should show if the analysis can be performed on original-sized materials with a large liquid pycnometer (LP, volume of about 280,cm3) or a self-made air pycnometer (AP). When materials of particle size up to 16,mm and/or of very different raw density were analyzed with the LP, the differences between parallel measurements were considerably greater than those of fine-textured soils and than those expected from repeated filling of the LP with water. They are ascribed mainly to the inhomogeneity of the samples and less to measuring errors. Consequently, the LP used seems to be suitable for the determination of particles with constituent size of up to 3,cm. However, the volume determination of every sample has to be performed at least twice. If the results do not meet the required precision, more repetitious measurements have to be performed, or the sample amount has to be enlarged. The same determination with the AP led to comparable and plausible results only in the case of water and of materials with compact constituents of relatively great size mainly (sand and fine gravel), when the samples were oven-dry, air-dry, or fairly moist. The results of the other materials were comparable, when the same sample preparation was performed as with liquid pycnometry (heating-up in water) and when they were covered by water in the measuring cell during measurement. The deviations from LP measurements were reduced, when measuring was performed by increasing air-pressure conditions (100 hPa) instead of lowering (,300 hPa), but to an insufficient degree. The reason for erroneous results was attributed to the existence of adsorbed air on particle surfaces (dry materials) and the evaporation of water during the measuring step (moist samples), respectively. [source] | ||||||||||