COVARIANCE ANALYSIS WITH A COVARIATE INTERACTION: AN EXAMPLE OF A SIMPLE LINEAR REGRESSION COMPARISON TECHNIQUE

Many real data sets that would normally lend themselves to being analyzed by an analysis of covariance, have a covariate interaction present with one or more of the factors in the experiment. Because this violates the assumption of same-slope covariate effect across all treatments, an analysis of covariance should not be performed. The course normally taken when there is such an interaction is to derive regression equations for the dependent variable as a function of the covariate, at each level of the factor(s) being tested. A general linear model F-test can then be used to test whether there are any overall differences between the regression lines. A technique that uses two mathematical distance measures to detect regression line differences once a significant general linear model F-test is obtained is illustrated. Applying these distance measures enables us to perform modified multiple comparisons of the regressions without resorting to the use of multiple pairwise general linear model F-tests, which inflate the Type I error rate. with this method, we are able to incorporate both factor and covariate information into the analysis to overcome the covariate-factor interaction problem

NEW TOOLS FOR NEW TIMES

The purpose of this presentation is to challenge statisticians to develop new tools needed by modern scientists. We are in the midst of a Scientific Revolution being driven by computers and the internet. Scientists are gathering huge amounts of data on the usual measurements while continually developing new instruments for new measurements. Data sets full of measurements which may pertain to the scientist\u27s research are easily available on the internet. Scientists are being overwhelmed with data. Agricultural producers and consumers are asking for more information. Scientists need new tools to evaluate variation. They need help with sampling - numbers of observations required and proper sampling schemes. Examples and suggestions will be offered. Statistical Process Control as applied to farming systems will be discussed

Bringing an emphasis on technical writing to a freshman course in electrical engineering

Includes bibliographical references (page 41).We have recently added a strong writing component to one of our freshman courses in electrical engineering. The students prepared two kinds of reports—memoranda and formal engineering project reports. Our instructional objectives were to execute well these two forms: to write with a professional tone, and to make good choices about which technical material to include. To meet these objectives, model memos and engineering project reports were developed, lectures about these memos and reports were presented, a Web site for the course was developed, the technical aspects of the reports were graded by a student hourly grader, the writing aspects of the reports were evaluated by a professor, and followup debriefings were conducted at the lecture class meetings. We report on the development process and discuss student response to the course

Thermal and Mechanical Properties of Compression-Molded pMDI-Reinforced PCL/Gluten Composites

Many biopolymers and synthetic polymers composites were developed by different researchers for environmental protection and for cost reduction. One of these composites is polycaprolactone (PCL) and vital wheat gluten or wheat flour composites were prepared and compatibilized with polymeric diphenylmethane diisocyanate (pMDI) by blending and compression-molding. PCL/pMDI blend exhibited glass transition (Tg) at -67 °C (0.20 J/g/ °C) and vital gluten at 63 °C (0.45 J/g/ °C), whereas no Tg was recorded for wheat flour. Although Tg was unmistakable for either PCL or gluten, all composite exhibited one Tg, which is strong indication of interaction between PCL and the fillers. Several samples amongst the blended or compression-molded composites exhibited no Tg signifying another confirmation of interaction. The ΔH of the endothermic (melting) and the exothermic (crystallization) for PCL was decreased as the percentage of gluten or flour increased, whereas the overall ΔH was higher for all composites compared to the theoretical value. The presence of pMDI appeared to strengthen the mechanical properties of the composites by mostly interacting with the filler (gluten or flour) and not as much with PCL. The FTIR analysis ruled out covalent interaction between PCL, pMDI, or the fillers but suggested the occurrence of physical interactions. Based on the data presented here and the data published earlier, the presence of pMDI did not change the nature of interaction between PCL and gluten, but it improved the mechanical properties of the composite

DISTANCE MEASURES IN POST HOC COMPARISONS OF TEMPERATURE GERMINATION QUADRATIC RESPONSE SURFACES

Generalized quadratic response surface models are used to describe seed germination at diurnally alternating cold and warm incubation temperatures for three Great Basin exotic plant species. The method of the F-statistic SSdrop is applied to determine whether the response surface models are equal. Two proposed distance measures are used as modified multiple comparison techniques for determining differences between surfaces. These measures prove useful in distinguishing between the species showing the highest germination response and the one showing the lowest response to the incubation temperature ranges studied

Impacts of fungal entomopathogens on survival and immune responses of Aedes albopictus and Culex pipiens mosquitoes in the context of native Wolbachia infections

Microbial control of mosquitoes via the use of symbiotic or pathogenic microbes, such as Wolbachia and entomopathogenic fungi, are promising alternatives to synthetic insecticides to tackle the rapid increase in insecticide resistance and vector-borne disease outbreaks. This study evaluated the susceptibility and host responses of two important mosquito vectors, Ae. albopictus and Cx. pipiens, that naturally carry Wolbachia, to infections by entomopathogenic fungi. Our study indicated that while Wolbachia presence did not provide a protective advantage against entomopathogenic fungal infection, it nevertheless influenced the bacterial / fungal load and the expression of select anti-microbial effectors and phenoloxidase cascade genes in mosquitoes. Furthermore, although host responses from Ae. albopictus and Cx. pipiens were mostly similar, we observed contrasting phenotypes with regards to susceptibility and immune responses to fungal entomopathogenic infection in these two mosquitoes. This study provides new insights into the intricate multipartite interaction between the mosquito host, its native symbiont and pathogenic microbes that might be employed to control mosquito populations

Racial capitalism and the US formula shortage: A policy analysis of the formula industry as a neocolonial system

The U.S. is currently experiencing a formula shortage and an infant feeding crisis that began with a formula recall and the hospitalization of 4 infants, 2 of whom died. Since 1981, governments around the world have been calling for an end to blatant human rights violations made by the commercial milk formula (CMF) industry. These practices not only involve targeting nutritionally vulnerable populations of mothers and newborns to turn a profit, but also actively undermining the implementation of policies, legislation, and regulatory oversight that might compromise their accumulation of wealth. In this paper we analyze the 2022 formula-shortage-as-infant-feeding-crisis through the lens of the history of colonialism and critical theory in the anthropology of reproduction. First, we provide an overview of the colonial roots of the formula industry from a global perspective. We then focus on how the mechanisms of racial exploitation remain entrenched in the U.S. approach to infant feeding policies, regulation and investment, setting the stage for the current infant feeding crisis. Through our analysis of the 2022 infant feeding crisis we demonstrate how the multinational CMF industry perpetuates racial capitalism and racialized health inequities and disparities through its operations as a neocolonial enterprise. Finally, we offer policy interventions and potential solutions that are grounded in structural interventions for more equitable, anticolonial, antiracist infant feeding systems

Large thermoelectric figure of merit at high temperature in Czochralski-grown clathrate Ba8Ga16Ge30

The Czochralski method was used to grow a 46-mm-long crystal of the Ba8Ga16Ge30 clathrate, which was cut into disks that were evaluated for thermoelectric performance. The Seebeck coefficient and electrical and thermal conductivities all showed evidence of a transition from extrinsic to intrinsic behavior in the range of 600–900 K. The corresponding figure of merit (ZT) was found to be a record high of 1.35 at 900 K and with an extrapolated maximum of 1.63 at 1100 K. This makes the Ba8Ga16Ge30 clathrate an exceptionally strong candidate for medium and high-temperature thermoelectric applications

Cross-cultural adaptation and content validation of the Infant Feeding Intentions Scale for Thai pregnant women

This study aimed to validate a translated and culturally adapted version of the Infant Feeding Intentions (IFI) Scale for use in Thailand. Prenatal breastfeeding intention is a strong indicator of breastfeeding initiation. The stronger the intention to breastfeed among pregnant women, the more likely breastfeeding will be initiated after childbirth and continue for an extended period. There are currently no IFI scales that have been validated for use in Thailand. The translation of the IFI scale from English to Thai was conducted through a six-stage approach that included initial translation, synthesis of translations, back-translation, expert committee review for content validity, reliability testing, and submission of the translated IFI to notify the scale developers. Both Item and Scale Content Validity Indices equaled 1, scored by five experts, who also validated the content for cross-cultural adaptation. The final Thai IFI (T-IFI) scale demonstrated high content validity. A total of 30 Thai pregnant women participated in the reliability testing. The Cronbach’s alpha of the 5-item T-IFI scale was 0.857, which indicated satisfactory internal consistency. The T-IFI scale demonstrated high content validity and was culturally appropriate for use in a Thai-speaking population. It has potential to strengthen assessments of prenatal infant feeding intention among pregnant women in Thailand