An Appreciation

To the Officers and Soldiers of the Twentieth Engineers and Attached Service Troops

Scholastic Records and Personality and Character Traits of the Public-school Trained and the Parochial-trained Students of the Graduating Class of 1952, Central High School, Aberdeen, South Dakota

For many years at Aberdeen, South Dakota, a difference of opinion has existed regarding the relative academic achievement, rank in class, and social adjustments of the students in the public school system and parochial -school system. The advocates of the two school systems have base their opinions on observations only and without the benefit of statistical evidence. To present impartial evidence upon which the proponents may form a more logical conclusion was the purpose of the investigator. The purpose of this study was to compare the students who had received the first nine years of their training in a parochial school with those who had received their training in a public school to see if there were any statistical differences in their performance during the last three years of their high-school training in the public school. They were compared in mental ability, academic achievement, rank in class, and social ability development by the investigation cf the high school records of the graduating class of 1952. The school performances made by these students grouped into their respective origins were the records used in making the comparisons

Textual affinities of Papyrus Bodmer XV (p75)

https://place.asburyseminary.edu/ecommonsatsdissertations/2093/thumbnail.jp

Renormalisation-theoretic analysis of non-equilibrium phase transitions II: The effect of perturbations on rate coefficients in the Becker-Doring equations

We study in detail the application of renormalisation theory to models of cluster aggregation and fragmentation of relevance to nucleation and growth processes. In particular, we investigate the Becker-Doring (BD) equations, originally formulated to describe and analyse non-equilibrium phase transitions, but more recently generalised to describe a wide range of physicochemical problems. We consider here rate coefficients which depend on the cluster size in a power-law fashion, but now perturbed by small amplitude random noise. Power-law rate coefficients arise naturally in the theory of surface-controlled nucleation and growth processes. The noisy perturbations on these rates reflect the effect of microscopic variations in such mean-field coefficients, thermal fluctuations and/or experimental uncertainties. In the present paper we generalise our earlier work that identified the nine classes into which all dynamical behaviour must fall by investigating how random perturbations of the rate coefficients influence the steady-state and kinetic behaviour of the coarse-grained, renormalised system. We are hence able to confirm the existence of a set of up to nine universality classes for such BD systems.Comment: 30 pages, to appear in J Phys A Math Ge

Use of an index to reflect the aggregate burden of long-term exposure to criteria air pollutants in the United States.

Air pollution control in the United States for five common pollutants--particulate matter, ground-level ozone, sulfur dioxide, nitrogen dioxide, and carbon monoxide--is based partly on the attainment of ambient air quality standards that represent a level of air pollution regarded as safe. Regulatory and health agencies often focus on whether standards for short periods are attained; the number of days that standards are exceeded is used to track progress. Efforts to explain air pollution to the public often incorporate an air quality index that represents daily concentrations of pollutants. While effects of short-term exposures have been emphasized, research shows that long-term exposures to lower concentrations of air pollutants can also result in adverse health effects. We developed an aggregate index that represents long-term exposure to these pollutants, using 1995 monitoring data for metropolitan areas obtained from the U.S. Environmental Protection Agency's Aerometric Information Retrieval System. We compared the ranking of metropolitan areas under the proposed aggregate index with the ranking of areas by the number of days that short-term standards were exceeded. The geographic areas with the highest burden of long-term exposures are not, in all cases, the same as those with the most days that exceeded a short-term standard. We believe that an aggregate index of long-term air pollution offers an informative addition to the principal approaches currently used to describe air pollution exposures; further work on an aggregate index representing long-term exposure to air pollutants is warranted

Business practices in small firms in developing countries

Management has a large effect on the productivity of large firms. But does management matter in micro and small firms, where the majority of the labor force in developing countries works? We develop 26 questions that measure business practices in marketing, stock-keeping, recordkeeping, and financial planning. These questions have been administered in surveys in Bangladesh, Chile, Ghana, Kenya, Mexico, Nigeria and Sri Lanka. We show that variation in business practices explains as much of the variation in outcomes – sales, profits and labor productivity and TFP – in microenterprises as in larger enterprises. Panel data from three countries indicate that better business practices predict higher survival rates and faster sales growth. The association of business practices with firm outcomes is robust to including numerous measures of the owner’s human capital. We find that owners with higher human capital, children of entrepreneurs, and firms with employees employ better business practices

Assessment of potential risk levels associated with U.S. Environmental Protection Agency reference values.

The U.S. Environmental Protection Agency (U.S. EPA) generally uses reference doses (RfDs) or reference concentrations (RfCs) to assess risks from exposure to toxic substances for noncancer health end points. RfDs and RfCs are supposed to represent lifetime inhalation or ingestion exposure with minimal appreciable risk, but they do not include information about the estimated risk from exposures equal to the RfD/RfC. We used results from benchmark dose modeling approaches recently adopted for use in developing RfDs/RfCs to estimate the risk levels associated with exposures at the RfD/RfC. We searched the U.S. EPA Integrated Risk Information System (IRIS) database and identified 11 chemicals with oral RfDs and 12 chemicals with inhalation RfCs that used benchmark dose modeling. For assessments with sufficient model information, we found that 16 of 21 (76%) of the dose-response models were linear or supralinear. We estimated the risk from exposures at the established RfDs and RfCs for these chemicals using a linear dose-response curve to characterize risk below the observed data. Risk estimates ranged from 1 in 10,000 to 5 in 1,000 for exposures at the RfDs, and from 1 in 10,000 to 3 in 1,000 for exposures at the RfCs. Risk estimates for exposures at the RfD/RfC values derived from sublinear dose-response curves ranged from 3 in 1,000,000,000 to 8 in 10,000. Twenty-four percent of reference values corresponded to estimated risk levels greater than 1 in 1,000; 10 of 14 assessments had points of departure greater than the no-observed-adverse-effect levels. For policy development regarding management of cancer risks, the U.S. EPA often uses 1 in 1,000,000 as a de minimis risk level. Although noncancer outcomes may in some instances be reversible and considered less severe than cancer, our findings call into question the assumption that established RfD and RfC values represent negligibly small risk levels