Determination by the radioactive indicator method of the retention and stability of thiabendazole in treated Valencia oranges

1970 ◽  
Vol 6 (2) ◽  
pp. 379-384 ◽  
Author(s):  
Ch. Rosenblum ◽  
H. T. Meriwether
Keyword(s):  
Indicator Method ◽  
Radioactive Indicator

Use of the radioactive indicator method to determine mean gas velocity through a porous medium

1971 ◽  
Vol 7 (3) ◽  
pp. 279-284
Author(s):  
M. D. Krivitskii ◽  
R. N. Krigman ◽  
S. V. Kuznetsov ◽  
S. N. Nedviga ◽  
V. M. Smelash
Keyword(s):  
Porous Medium ◽  
Gas Velocity ◽  
Indicator Method ◽  
Radioactive Indicator

The Effect of Partly Missing Covariates on Statistical Power in Randomized Controlled Trials With Discrete-Time Survival Endpoints

Methodology ◽  
2017 ◽  
Vol 13 (2) ◽  
pp. 41-60
Author(s):  
Shahab Jolani ◽  
Maryam Safarkhani
Keyword(s):  
Randomized Controlled Trials ◽  
Discrete Time ◽  
Treatment Effect ◽  
Survival Data ◽  
Controlled Trials ◽  
Missing Covariates ◽  
Indicator Method ◽  
Imputation Methods ◽  
Randomized Controlled ◽  
Baseline Covariates

Abstract. In randomized controlled trials (RCTs), a common strategy to increase power to detect a treatment effect is adjustment for baseline covariates. However, adjustment with partly missing covariates, where complete cases are only used, is inefficient. We consider different alternatives in trials with discrete-time survival data, where subjects are measured in discrete-time intervals while they may experience an event at any point in time. The results of a Monte Carlo simulation study, as well as a case study of randomized trials in smokers with attention deficit hyperactivity disorder (ADHD), indicated that single and multiple imputation methods outperform the other methods and increase precision in estimating the treatment effect. Missing indicator method, which uses a dummy variable in the statistical model to indicate whether the value for that variable is missing and sets the same value to all missing values, is comparable to imputation methods. Nevertheless, the power level to detect the treatment effect based on missing indicator method is marginally lower than the imputation methods, particularly when the missingness depends on the outcome. In conclusion, it appears that imputation of partly missing (baseline) covariates should be preferred in the analysis of discrete-time survival data.

Indicators of Sustainable Development of the Province of Warmia and Mazury in the Environmental Aspect

2016 ◽  
Vol 11 (3) ◽  
pp. 299-309
Author(s):  
Mirosława Witkowska-Dąbrowska
Keyword(s):  
Quality Of Life ◽  
Sustainable Development ◽  
Data Bank ◽  
Local Data ◽  
Indicator Method ◽  
Environmental Aspect ◽  
The Sustainable Development ◽  
Assessment Indicator ◽  
Area Unit

The purpose of this study has been to identify the degree of sustainability in the development of the Province of Warmia and Mazury. The theoretical and empirical investigations were conducted between 2003-2014 based on data from the Local Data Bank. Using a comparative indicator method, 20 indicators were developed, with different directions of preference. The evaluation involves the concept of uniform preference, hence the higher the assessment indicator, the better the situation in the evaluated area unit. Our studies on the sustainable development of the Province of Warmia and Mazury suggest that the indicators measuring the environmental dimension and consequently the quality of life of the residents (in this aspect) score higher than the country's average values. It is also optimistic that some progress, however small, can be seen in this area based on the analyzed dynamics of changes.

Preparation of Strong Acid Catalysts by Sulfate Treatment of Calcined Boehmite

1992 ◽  
Vol 57 (11) ◽  
pp. 2241-2247 ◽  
Author(s):  
Tomáš Hochmann ◽  
Karel Setínek
Keyword(s):  
Catalytic Activity ◽  
Surface Area ◽  
Aluminum Sulfate ◽  
Solid Acid ◽  
Strong Acid ◽  
Acid Strength ◽  
Solid Acid Catalysts ◽  
Acid Catalysts ◽  
Preparation Methods ◽  
Indicator Method

Solid acid catalysts with acid strength of -14.52 < H0 < -8.2 were prepared by sulfate treatment of the samples of boehmite calcined at 105-800 °C. Two preparation methods were used: impregnation of the calcined boehmite with 3.5 M H2SO4 or mixing of the boehmite samples with anhydrous aluminum sulfate, in both cases followed by calcination in nitrogen at 650 °C. The catalysts were characterized by measurements of surface area, adsorption of pyridine and benzene, acid strength measurements by the indicator method and by catalytic activity tests in the isomerization of cyclohexene, p-xylene and n-hexane. Properties of the catalysts prepared by both methods were comparable.

Binding of calcium, lead, and copper(II) cations to galactaric and 2,5-furandicarboxylic acids and to D-galacturonic acid and its derivatives

1986 ◽  
Vol 51 (5) ◽  
pp. 1150-1159 ◽  
Author(s):  
Rudolf Kohn ◽  
Ján Hirsch
Keyword(s):  
Galacturonic Acid ◽  
Uronic Acid ◽  
Indicator Method ◽  
Cu Complex ◽  
Carboxylate Groups ◽  
Counter Ions ◽  
Galactaric Acid ◽  
Furandicarboxylic Acid ◽  
The Difference ◽  
Calcium Lead

The binding of Ca2+, Pb2+, and Cu2+ ions to galactaric and 2,5-furandicarboxylic acids and of Pb2+ and Cu2+ ions to D-galacturonic acid, its α-methylglycoside, and (methyl-4-deoxy-α-D-galactopyranosid)uronic acid was evaluated in terms of the activity coefficients of the counter-ions and the degrees of their association with the carboxylate groups of the acids. The activity of Ca2+ ions was determined by the metallochromic indicator method with tetramethylmurexide, that of Pb2+ and Cu2+ ions, with ion specific electrodes. Galactaric acid bids 89.5% Ca2+ ions, practically all (99.9%) Pb2+ ions and nearly all (98.6% Cu2+ ions, mostly with the formation of insoluble salts. As little as 7.6% Ca2+, 34.0% Pb2+, and 23.9% Cu2+ were bound to 2,5-furandicarboxylic acid in the form of soluble complexes, and slightly more, 4.1% Ca2+, 43.9% Pb2+, and 38.0% Cu2+, to D-galacturonic acid. The difference in the degrees of binding to galactaric acid and 2,5-furandicarboxylic acid is due to the different flexibility of their molecular skeletons. The activities of Pb2+ and Cu2+ ions in solutions of salts of D-galacturonic acid and its derivatives indicate that the OH group at C(4) of D-galacturonic acid takes part in the complexation. For the Pb2+ complex, the OH group at C(1) of the unsubstituted acid in the β-anomeric form also seems to participate in the complexation; this is not the case with the similar Cu complex.

scholarly journals Effect of the Feed Additive Clinoptilolite (ZeoFeed) on Nutrient Metabolism and Production Performance of Laying Hens

2010 ◽  
Vol 79 (9) ◽  
pp. S29-S34 ◽  
Author(s):  
Miroslav Macháček ◽  
Vladimír Večerek ◽  
Nora Mas ◽  
Pavel Suchý ◽  
Eva Straková ◽  
...  
Keyword(s):  
Drinking Water ◽  
Laying Hens ◽  
Laying Hen ◽  
Production Performance ◽  
Feed Consumption ◽  
Control Group ◽  
Egg Weight ◽  
Indicator Method ◽  
Balance Tests ◽  
Gross Energy

The aim of this study was to assess the effects of two levels of clinoptilolite administered in feed (2% and 4%) on some selected performance indicators, metabolic utilization of basic nutrients and the health status of laying hens. The selected 24 Bovans Goldline hybrid laying hens were divided into three equal groups, two experimental groups (E1 and E2) and one control group (C). The laying hens were housed individually in cages with an automatic supply of drinking water, manual feeding, in a setting with controlled light and temperature regimens. Hens from individual groups were all fed a complete feed mix of the same composition and the only difference was in clinoptilolite supplementation: feed mixes for E1 and E2 groups contained 2% and 4% of clinoptilolite (commercial additive ZeoFeed) respectively, replacing the same amounts of wheat. The hens received feed mixes and drinking water ad libitum. During this 28-day experiment, feed consumption and the number and weight of eggs laid were monitored individually for each hen. At the end of the experiment, the balance test using the indicator method (Cr2O3) was performed in all eight hens in each of the groups. The results of balance tests were then used to calculate the metabolic utilization of selected nutrients (nitrogen, fat, ash, nitrogen-free extracts, starch, gross energy, Ca, P). After the balance tests, blood samples for haematological and biochemical examinations were collected via puncture of the vena basilica. The addition of 2% clinoptilolite to feed mix resulted in a highly significant (P ⪬ 0.01) increase in mean egg weight to 64.69 g, but the addition of 4% clinoptilolite in group E2 resulted in a highly significant (P ⪬ 0.01) decrease in mean egg weight to 62.20 g compared to the control (63.73 g). Moreover, daily feed mix consumption in group E1 decreased to 114 g per one laying hen/day compared to the controls (118 g per one laying hen/day). In group E2 (4% clinoptilolite), daily consumption of feed mix increased compared with the controls to 124 g. The 2% clinoptilolite supplementation of E1 group feed slightly increased metabolic utilization of fat, nitrogen-free extracts, starch and gross energy compared to group C. Results of haematological test of the hens’ blood showed significant changes in haemoglobin, whose values in groups C and E1 were significantly higher (P ⪬ 0.05) than in group E2. Differences in the values of the biochemical indicators monitored (total protein, glucose, cholesterol, triacylglycerols, calcium, phosphorus, magnesium and the AST enzyme) between group C and experimental groups E1 and E2 were not significant and remained within the range of reference values.

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