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The Assessment of the Calving Interval at Cows in the Mountain Area

Abstract

For an effective, in determining the index „Calving Interval“ we take into consideration the two components of each interval: service period (SP) and duration of gestation (DG). In order to obtain the optimal interval between calving (365 days) the cow should become gestant at 81 days after calving, because along with 284-285 days, length of gestation, to provide 305 days for normal lactation and 60 days for the rest of the breast enough for the formation of the udder for the next lactation.

The frequency curve has a single peak, 43.5% placed around 361 days after which the frequencies fall along a period of time long enough. The probably average of „CI“ of 360 days, which corresponds to the class with highest frequency, shows that the fecundity is good and that it can provide a rest for brest for 55 days in the case of normal lactations of 305 days.

The 42 days difference between the arithmetic mean of the „CI“ (402 days ago) and the likely media (360 days) is caused by the presence of breeding disorders. The large values of the coefficient of variance is due to the very long ranges as well as very short intervals of calving interval.

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Determinant Factors of Cow’s Milk Production in the Mountain Area

Abstract

The production of milk, the quantity of fat respectively constitute the main criterion of assessment of dairy cows in the mountain area and downhill. The average performance in the succession of eight lactations per total lactation is 3420.67 kg, and per normal lactation is 3209.20 kg milk. The limits vary between 1506 kg of milk and 8835 kg milk recorded for lactation and 1506 kg of milk and 7322 kg milk for normal lactation. The study of statistical parameters of index of the total duration of lactation allows us to affirm that the cows from the herd studied have the genetic potential to increase lactation beyond the limits of normal lactation of 305 per days. Milk production per day is higher with + 0.45 kg per total lactation than normal lactation. Extension of lactation and breast resting shortening represents loss of milk production in both current lactation and the next lactation. To estimate the effect of localities was used the analysis of variance within samples. Raw data tables have been processed to create tables of variances between herds of the 6 localities and within the herd in each locality. The influence of the locality on the milk production is null.

The output production of milk cows has as enablers: daily output and duration of lactation on her. The raise of the productive cows milk level in the mountain area and hence income breeders is achievable through the integration and expansion of biotechnology.

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The Evaluation of Analytical Performance of Immunoassay Tests by Using Six-Sigma Method

Summary

Background: The Six-Sigma Methodology is a quality measurement method in order to evaluate the performance of the laboratory. In the present study, it is aimed to evaluate the analytical performance of our laboratory by using the internal quality control data of immunoassay tests and by calculating process sigma values. Methods: Biological variation database (BVD) are used for Total Allowable Error (TEa). Sigma values were determined from coefficient of variation (CV) and bias resulting from Internal Quality Control (IQC) results for 3 subsequent months. If the sigma values are ≥6, between 3 and 6, and <3, they are classified as »world-class«, »good« or »un - acceptable«, respectively. Results: A sigma value >6 was found for TPSA and TSH for the both levels of IQC for 3 months. When the sigma values were analyzed by calculating the mean of 3 months, folate, LH, PRL, TPSA, TSH and vitamin B12 were found >6. The mean sigma values of CA125, CA15-3, CA19-9, CEA, cortisol, ferritin, FSH, FT3, PTH and testosteron were >3 for 3-months. However, AFP, CA125 and FT4 produced sigma values <3 for varied months. Conclusion: When the analytical performance was evaluated according to Six-Sigma levels, it was generally found as good. It is possible to determine the test with high error probability by evaluating the fine sigma levels and the tests that must be quarded by a stringent quality control regime. In clinical chemistry laboratories, an appropriate quality control scheduling should be done for each test by using Six-Sigma Methodology.

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Intra-Subject Variability of 5 Km Time Trial Performance Completed by Competitive Trained Runners

performance data drawn from sessions 3-6, following a familiarisation TT in session two. As a measure of typical error of individuals’ mean score as per Hopkins (2000) , intra-subject absolute standard error of measurement (SEM) was calculated in addition to the coefficient of variance (CV) to provide relative measure of variance of TT variables (time as well as mean and peak speed, HR and RPE). The CV, suggested when considering performance testing, was used in order to provide comparative data to previous studies, with an analytical goal of the data being 10% or below

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Investigations of operational driving loads of bucket chains and manoeuvre hoisting winches on multi-bucket dredgers

Investigations of operational driving loads of bucket chains and manoeuvre hoisting winches on multi-bucket dredgers

The paper concerns problems of preliminary designing of bucket dredgers' power plants. This paper presents results of investigations of six bucket dredgers in service. The operational investigations consisted in measuring the parameters which characterize working conditions of two main receivers of mechanical energy: bucket chains and swing winches. In the paper characteristics of disposition of loading of bucket chains and swing winches are presented. They covered average value, standard deviation and coefficient of variance of loading disposition mutability. Examples of load distributions of chains' and group of swing winches on chosen dredgers during some period of time were given. Conclusions in view to average values of main receivers of mechanical energy and coefficients of variance of loadings spred were formulated. Results of investigations of dependence of average loadings of main receivers on their nominal power were presented. The results of work will be used in creation of random models describing real conditions of operation of power plant elements of dredgers.

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Is the Taxon of Altaic Languages Natural or Artificial?

Is the Taxon of Altaic Languages Natural or Artificial?

The article considers if the taxon of Altaic languages natural enough to call it a good classification. The more compact a taxon, the more natural it is. The article deals with the peculiarities of functioning of labial consonants in the languages of the Altaic language unity and the peculiarities of functioning of labial consonants in subgroups, groups, families and other language taxa of world languages. The analysis is made with the help of such statistical methods as the coefficient of variance, the confidence interval, Chi-square and t-test. The linguistic conclusions on the similarity of functioning of labial consonants are made on the basis of the statistical criteria. It is possible to establish the typological distances between some language taxa (Turkic, Finno-Ugric, Tungus-Manchurian, Slavonic, etc.) on the values of the t-test.

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Comparison of a mobile application to estimate percentage body fat to other non-laboratory based measurements

Summary

Study aim: The measurement of body composition is important from a population perspective as it is a variable associated with a person’s health, and also from a sporting perspective as it can be used to evaluate training. This study aimed to examine the reliability of a mobile application that estimates body composition by digitising a two-dimensional image. Materials and methods: Thirty participants (15 men and 15 women) volunteered to have their percentage body fat (%BF) estimated via three different methods (skinfold measurements, SFM; bio-electrical impedance, BIA; LeanScreenTM mobile application, LSA). Intra-method reproducibility was assessed using intra-class correlation coefficients (ICC), coefficient of variance (CV) and typical error of measurement (TEM). The average measurement for each method were also compared. Results: There were no significant differences between the methods for estimated %BF (p = 0.818) and the reliability of each method as assessed via ICC was good (≥0.974). However the absolute reproducibility, as measured by CV and TEM, was much higher in SFM and BIA (≤1.07 and ≤0.37 respectively) compared with LSA (CV 6.47, TEM 1.6). Conclusion: LSA may offer an alternative to other field-based measures for practitioners, however individual variance should be considered to develop an understanding of minimal worthwhile change, as it may not be suitable for a one-off measurement.

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Quantitative Analysis of Polycyclic Aromatic Hydrocarbons (PAHs) Cited by the United States Food and Drug Administration

Abstract

The yields of 16 polycyclic aromatic hydrocarbons (PAHs) were determined from cigarette mainstream smoke condensate extracts using Gas Chromatography- Tandem Mass Spectrometry (GC-MS/MS). The method has been validated for ISO and Health Canada Intense (HCI) smoking protocols. Quantifiable levels (ISO means 0.16 to 365 ng/cig; HCI means 0.33 to 1595 ng/cig; n = 30) of 15 PAHs were found in the Kentucky reference cigarette K3R4F. The coefficient of variance (CV) was derived from ten determinations each run in triplicate. The CV range was 8.7% to 24.8% (ISO) and 6.6% to 24.3% (HCI). The limit of detection (LOD) based on empirical precision was ≤ 0.06 ng/cig (ISO) and ≤ 0.20 ng/cig (HCI) for all components except naphthalene (2.89 and 9.62 ng/cig, respectively). The yields from 5 unspecified branded cigarettes (Samples A-E) and 2 other reference cigarettes, K1R5F and the CORESTA monitor CM7, were determined under ISO smoking conditions. The same 15 PAHs were detected as in the K3R4F; however, cigarettes with lower yields of total particulate matter (TPM) were found to contain significantly less PAHs. One component was measured below the limit of quantification (LOQ) in Sample E and 2 components were < LOQ in the K1R5F.

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Variability in Soil Properties as Influenced by Different Land Use Types in an Ultisols of the Tropical Region, Delta State, Nigeria

Abstract

The study was conducted in the 2010 - 2012 cropping seasons in a typical ultisols of the tropics. The aim was to assess variability in soil properties as influenced by three land use types namely: oil palm plantation, maize and yam cultivated lands. The study consisted of both field and laboratory studies. The field study was made up of a land use that was carefully surveyed, mapped into 20 × 30 m2 and plotted into 5 homogenous units of 0.25 ha. Soil samples were randomly augered by grid survey at 5 m equidistant points and surface 0-15 cm samples collected using screw auger for laboratory analysis of the particle size distribution and some chemical characteristics of the soils in the different land use types. Variation in properties within land use types was measured by estimating the coefficient of variance. The results of the study showed that particle size distribution varied from sand in the oil palm land use type to sandy loam in the maize and yam land use types. The variant ratio tests were 84.4%, for sand, 0.51% for silt and 27.4% for clay, and were less variable. The soil pH ranged from strongly acid (5.25) to moderate acid (5.65) and less variable (CV% = <15%). The variant ratio test was statistically not significant (10.7%). The organic carbon (35.7%), total nitrogen (34.5%) and available phosphorus (27.2%) variant ratio tests were non-significant and less variable. The exchangeable bases, exchange acidity and ECEC were also non significant and less variable. The results indicated clearly that variability could occur within soil units and therefore called for caution in assessing uniformity of soil properties within soil areas under cultivation

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MRI reduces variation of contouring for boost clinical target volume in breast cancer patients without surgical clips in the tumour bed

on CT- and MRI-based approach. Inter-observer coefficients of variance (CoV – ratio between SD and mean value) and ratios between the smallest and largest volume were determined for each case and modality. Inter-observer conformity index was calculated based on the generalized formalism (CI gen ), which is independent of the number of the analysed volumes. 29 It equals the sum of intersections of all possible volume-pairs divided by the sum of their unions. Contouring accuracy We used the EC as a surrogate for the “ground truth” contour. Deviations from EC

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