Appropriate Analysis Of Variance Research Articles

Comparison of in vitro Maturation Media on Cattle Oocytes after in vitro Embryo Production

The study was conducted to compare differences in vitro maturation media and their effect on subsequent in vitro embryo production. The study procedures were approved by the agricultural research council animal ethics committee (Ref no: APAEC 2020/05) and the Tshwane university of technology animal research ethics committee (Ref no: AREC 2021/08/004). Follicular fluid containing a suspension of oocytes was retrieved from ovaries through aspiration and slicing techniques. The retrieved oocytes were graded and randomly matured into four media (TCM199, Vitromat Protect, and BO IVM®) groups for 22 h, evaluated for polar body extrusion, fertilized through their respective in vitro fertilization media, and evaluated for pronucleus status. Presumptive zygotes were further cultured in vitro in their respective media, incubated for either 18 or 96 h, and evaluated for cleavage rates. The data was subjected to an appropriate analysis of variance. Student's Least Significant Differences (t-LSD) was calculated at a 5% significance level to compare means of significant treatment effects. The BO-IVM® (57.4%), TCM 199 (55.6%), and VitroMat Protect® (54.0%) recorded higher results than EGF (26.9%) for polar body formation on oocytes (P<0.05). Vitrofert® medium recorded a higher percentage (43.3%) of total fertilization rate when compared to the other media (P<0.05). VitroCleave Plus® medium recorded a higher total cleavage rate (43.3%) as compared to the other media (P<0.05). In conclusion, TCM 199, BO-IVM®, and VitroMat Protect® media rendered higher results of oocyte polar body extrusion rates compared to the EGF medium. Vitrofert® medium recorded a higher percentage (43.3%) of total fertilization rate when compared to the other media. Higher embryo development (4-8 cells and total cleavage) rates were observed in VitroCleave Plus® medium. Overall, the introduced media (VitroMat Protect®) and its media suite successfully adapted to the laboratory environment in South Africa (SA) and can therefore be adopted for optimizing the in vitro Embryo Production (IVEP) of cattle oocytes.

A Comparative Study on the Reproductive Performance of South African Indigenous Sheep Breeds Following Oestrus Synchronization

The aim of the study was to compare the effect of age and live body weight on the oestrus response, duration, pregnancy rate and lambing rate among South African indigenous sheep breeds (Zulu sheep = 36, Bapedi sheep = 26, Damara sheep = 10 and Namaqua Afrikaner sheep = 9). Control Intravaginal Drug Release Dispensers (CIDR’s) were inserted into the vagina for 10 days. The twitching of tail and standing to be mounted in the presence of the teaser ram were most targeted signs of oestrus. Data were subjected to an appropriate analysis of variance (ANOVA). The scores were subjected to 1:1 Frequency table and a Chi-Square (&chi;²) test for the equal proportions test. One Bapedi ewe loss CIDR before removal date hence was removed from the experimental animals. All Namaqua Afrikaner (100%) ewes responded to the synchronization protocol with the longest oestrus duration (70.7±7.2 h). However, Namaqua Afrikaner sheep scored the lowest rate for conception (44%) and lambing (44%). No significant different (P>0.05) observed for the onset of oestrus among the breeds. Four years old ewes responded better to oestrus synchronization than ≤3, 5 and ≥6 years. Nevertheless, ewes that were ≥6 years old had higher conception rate (94%) and lambing rate (84%). Zulu sheep had higher (89%) lambing rate than Damara (60%) sheep and Namaqua Afrikaner (44%) sheep. Lighter ewes had higher conception (83%) and lambing rate (90%) than heavier (77 and 64%) and moderate (68 and 78%) weights, respectively. In conclusion, Zulu sheep were more fertile than other South African indigenous breeds following oestrus synchronization. On the other hand, young ewes (≤3 years) produced heavier lambs and weaning weight but had higher mortality rate due to inexperience.

Assessing performance-use preferences through an institutional logics lens

PurposeThe purpose of this paper is to examine the influence of shared cognitive frames, in particular, that of institutional logics, on the deployment and use of performance measurement systems (PMSs) in the public sector.Design/methodology/approachUsing novel priming techniques derived from behavioral and social psychology, three institutional logics – the public, market-managerial and professional logics – are differentially surfaced in three independent experimental groups. The influence of these primed institutional logics on performance measurement use preferences are then empirically assessed using appropriate analysis of variance techniques.FindingsContrary to theoretical predictions, the paper reveals logic congruence regarding some uses of PMSs in the public sector, and divergence regarding others. Individuals applying a public logic were more likely to propose performance measurement use for strategic planning or strategic alignment; while those applying a professional logic were more likely to propose performance measurement use for learning, compared to otherwise primed individuals.Research limitations/implicationsConsidering the sample size and the novelty of the priming tools, it is feasible that other potentially significant effects may have been missed.Originality/valueThe paper addresses a gap in literature regarding the influence of shared cognitive frames on performance measurement use in public sector organizations. The paper further presents priming techniques embedded within an experimental design as an appropriate method for the micro-level study of attitudes, preferences and judgments in the public sector.

Staff and student health and wellness at the Faculty of Medicine and Health Sciences, Stellenbosch University: current status and needs assessment

Background: Emphasis is currently placed on the importance of employee and student wellness initiatives. The aim was to assess staff and student health status at the Faculty of Medicine and Health Sciences (FMHS), Stellenbosch University (SU), and to conduct a wellness needs assessment.Methods: Online, self-administered questionnaires were used to collect data concerning staff and students. Additionally, students’ anthropometric and biochemical parameters were assessed. Summary statistics, correlation coefficients and appropriate analysis of variance were used for data analyses.Results: Data were obtained from staff (survey: n = 300) and students (screening: n = 536; survey: n = 330). Some 58% (n = 174) of staff had a self-reported BMI of ≥ 25 kg/m2 whilst mean screening values for all variables fell within normal reference ranges for students. In all, 78% (n = 232) of staff reported to exercise 150 min/week and 28% (n = 91) of students were sedentary for 8 h/day; 63% (n = 188) of staff expressed the need to make better food choices, 17% (n = 55) of students were aware of the need to change but experienced reluctance, and both staff and students felt dietary assistance would be beneficial (43% vs. 46%). In addition, 79% of staff (n = 208) and 42% of students (n = 138) reported being under constant pressure.Conclusion: Much can be done to improve the health and well-being of both staff and students at the FMHS, SU. Wellness is a multifactorial concept; as such, health-promotional strategies for classrooms and workplaces should consider all factors in order to provide a holistic approach and potentially identify those who are at risk of a sub-optimal wellness status.

Staff and student health and wellness at the Faculty of Medicine and Health Sciences, Stellenbosch University: current status and needs assessment

Background: Emphasis is currently placed on the importance of employee and student wellness initiatives. The aim was to assess staff and student health status at the Faculty of Medicine and Health Sciences (FMHS), Stellenbosch University (SU), and to conduct a wellness needs assessment.Methods: Online, self-administered questionnaires were used to collect data concerning staff and students. Additionally, students’ anthropometric and biochemical parameters were assessed. Summary statistics, correlation coefficients and appropriate analysis of variance were used for data analyses.Results: Data were obtained from staff (survey: n = 300) and students (screening: n = 536; survey: n = 330). Some 58% (n = 174) of staff had a self-reported BMI of ≥ 25 kg/m2 whilst mean screening values for all variables fell within normal reference ranges for students. In all, 78% (n = 232) of staff reported to exercise 8 h/day; 63% (n = 188) of staff expressed the ...

The association between tuberculosis and the development of insulin resistance in adults with pulmonary tuberculosis in the Western sub-district of the Cape Metropole region, South Africa: a combined cross-sectional, cohort study

BackgroundThe existence of a bi-directional relationship between tuberculosis (TB) and insulin resistance (IR)/diabetes has been alluded to in literature. Although diabetes has been linked to increased tuberculosis risk, the relationship between tuberculosis as a causative factor for IR remains unclear. The study aimed to determine if an association existed between tuberculosis and IR development in adults with newly diagnosed pulmonary tuberculosis at baseline. It was additionally aimed to document changes in IR status during TB follow-up periods.MethodsThis cross-sectional study evaluated ambulatory participants at baseline for IR prevalence via anthropometry, biochemistry and diagnostic IR tests [homeostasis model assessment-IR (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI)]. A prospective cohort sub-section study was additionally performed on approximately half of the baseline study population, who were followed-up at two and five months whilst on tuberculosis treatment. Summary statistics, correlation co-efficients and appropriate analysis of variance were used to describe and analyse data. Participants were excluded if they presented with other forms of tuberculosis, were HIV-positive, obese or had any pre-disposing IR conditions such as diabetes or metabolic syndrome.ResultsFifty-nine participants were included from August 2013 until December 2014 (33.95 ± 12.02 years old; 81.4% male). IR prevalence was 25.4% at baseline, determined by a calculated HOMA-IR cut-off point of 2.477. Patients with IR were younger (p = 0.04). Although the difference between IR levels in participants between baseline and follow-up was not significant, a decrease was observed over time. The majority of participants (61.0%) presented with a normal BMI at baseline. Mean baseline values of fasting glucose were within normal ranges (4.82 ± 0.80 mmol/L), whereas increased mean CRP levels (60.18 ± 50.92 mg/L) and decreased mean HDL-cholesterol levels (males: 0.94 ± 0.88 mmol/L; females: 1.14 ± 0.88 mmol/L) were found.ConclusionsThe study found an association between tuberculosis and IR development in newly diagnosed pulmonary tuberculosis patients. Although not significant, IR levels decreased over time, which could be indicative of a clinical improvement. A high prevalence of IR amongst young tuberculosis patients therefore highlights the need for early identification in order to facilitate a reversal of IR and prevent possible IR-related complications.

Automating the analysis of variance of orthogonal designs

A new algorithm is presented which for the wide class of orthogonal designs is capable of deducing the appropriate analysis of variance from the design only. As a consequence the use of a model equation for specifying the analysis becomes dispensable. The proposed approach can simplify the analysis of complex models with iterative crossing and nesting of factors, where treatment factors have fixed and plot factors have random effects. An implementation is described and its use is illustrated with several examples.

Variability of post-methionine load plasma homocysteine assays

Background: Numerous variations of the methionine load test are frequently used as dynamic function tests to assess homocysteine metabolism. Lack of standardization impedes inter-laboratory comparisons. Criteria based on biological variation are suggested to standardize the methionine load test. Methods: Weekly methionine load tests ( n=5) with blood sampling at 0, 4, 6 and 8 h were performed on 15 young men. For both basal and post-methionine load homocysteine measurements, total variance ( σ S 2), within-subject variance ( σ I 2), between-subject variance ( σ G 2) and analytical variance ( σ A 2) were calculated from an appropriate analysis of variance (ANOVA). Results: Plasma homocysteine concentrations measured 6 h after methionine loading had analytical, within-subject and between-subject coefficients of variation of 5.2%, 17.5% and 9.7%, respectively. Measurements at 4 h had a higher within-subject coefficient of variation. Adjustment of post-methionine load homocysteine concentrations for basal levels resulted in considerable increases of all the measures of variation. Conclusions: Adjustment of post-methionine load plasma homocysteine concentrations for basal levels does not improve the interpretation of changes in serial results due to the higher analytical and biological variance of adjusted concentrations. It is suggested that the methionine load test is standardized to a single, unadjusted homocysteine measurement at 6 h.

Consistency of the bootstrap procedure in individual bioequivalence

Recently, the concepts of population and individual bioequivalence have been proposed for assessing the bioequivalence of two drug formulations. Moment-based and probability-based measures of bioequivalence have led to criteria for deciding whether two formulations should be regarded as bioequivalent or not. The US Food and Drug Administration (1997) guidance recommended the use of bootstrap percentile intervals for this purpose. In this paper, we discuss theoretical properties such as consistency and accuracy of the recommended bootstrap intervals. We concentrate on individual bioequivalence and especially on the scaled versions of the moment-based as well as the probability-based measures as recommended by the US Food and Drug Administration. As estimates for the former, we consider those obtained from an appropriate analysis of variance and restricted maximum likelihood estimators under mixed effect models, whereas an unbiased estimator of the latter can be derived from corresponding relative frequencies.

ANOVAGEN: A Data Generation and Analysis of Variance Program for Use in Statistics Courses

This article describes a BASIC program (ANOVAGEN) for use in statistics courses. ANOVAGEN uses population parameters specified by the instructor to generate unique data for each student. The program also calculates the appropriate analysis of variance (ANOVA) for the unique data of each student. We describe the use of the program and provide samples of student and instructor output. ANOVAGEN helps demonstrate some fundamental concepts in ANOVA, reduces the time required for grading of unique statistical exercises, and encourages students to work independently. Other possible uses of ANOVAGEN, including uses in other courses, are described.

Measuring measuring errors.

The assessment of errors of measurement and their effects needs to take into account the structure of the data in which the errors occur. This is illustrated and the appropriate analysis of variance specified for a variety of contexts. The notion of an acceptable level of measurement error is discussed in terms of decision theory and illustrated by a simplified example.

The basic contrasts of an experimental design with special reference to the analysis of data

SUMMARY The least squares solution for a block design is considered in some detail for both the intrablock and the interblock cases. It leads to the identification of certain contrasts, here called basic, that are estimated independently and with efficiency factors that are readily determined. Basic contrasts indicate possible partitions of the treatment sum of squares and aid in the computation of the appropriate analysis of variance. Also they help to clarify the relationship between three methods of computing the analysis for the general case of block designs, namely those of (i) Tocher, (ii) Kuiper and Corsten and (iii) Wilkinson.

Hybrid Polynomial and Periodic Regression with and without Missing Observations

SUMMARY A model including polynomial and trigonometric terms useful in describing mortality and meteorological data is discussed. The appropriate analysis of variance for the cases with and without missing observations is presented. A comparison of the residulals from the least squares and two-stage solutions is made with indications that the least squares solution tends to yield errors consistent with the assumptions of independence and normality.

Differential performance on psychomotor tests by hospitalized acute and chronic mental patients.

This paper examined the tenability of the hypothesis that poor psychomotor test performance is prognostically favorable for chronic patients but prognostically unfavorable for acute patients. The acute group was defined as having been hospitalized less than two months on their initial hospitalization at the time of testing. The chronic group had been hospitalized virtually continuously for at least two years prior to testing. From a pool of 1,400 records, a sample of 683 cases which met the criteria was obtained. These were classified as acute/chronic and released/not released, and the data subjected to the appropriate analysis of variance. The results indicated that the acute and chronic groups were significantly different in terms of test performance, as were the released/not released groups, but that there was no evidence of the reversal required by the hypothesis. It was concluded that the hypothesis was not supported by these data.

Variation in Quantitative Characters of X&lt;SUB&gt;2&lt;/SUB&gt; Plant after Hybridization and Irradiation in Rice

The present paper describes some aspects of inducing genetic variation of polygenically controlled characters following the irradiation of two rice varieties and their hybrids. The data for the characters studied in X2 generations were analyzed by appropriate analysis of variance. In all the cases, the mean value of the irradiated population with respect to grain size character was almost the same as that of the non-irradiated control, while the variance of the irradiated population increased. On the other hand, for endosperm quality the irradiated populations showed increase in the mean value and the variance. The results obtained in the present experiment suggest that background genotypes played an important role in the manifestation of mutated characters