Abstract For the past two years, the authors have combined training on metacognition with skills identified by practitionersto teach undergraduate,civil engineering students how to evaluate the reasonableness,of structural analysis results. Metacognition is a sequence,of steps followed by a person to monitor and,improve,that,person’s own,cognitive performance,i n an,area., The practitioner skills taught fall into three categories: fundamental principles, approximations, and features of the solution. When combined, the training has resulted in a measurable increase in student ability to evaluate the reasonableness,of results. This paper,summarizes how,the training was incorporated in the classroom and homework assignments. Results from surveys, observations from interviews, and exam scores are presented to show the effect of the training on attitude, behavior and cognition. The paper concludes with suggestions on howthe training might be applied in other fields of engineering. Key Words Education Methods, Innovative Teaching Methods Preliminary Results from Teaching Students How to Evaluate the Reasonableness of Results James H. Hanson, Ph.D. Department of Civil Engineering, Rose-Hulman Institute of Technology Patrick D. Brophy, Ph.D. Department of Humanities and Social Sciences, Rose-Hulman Institute of Technology Abstract
OBJECTIVE:The National Cancer Institute established the Cancer Genetics Network (CGN) to support collaborative investigations into the genetic basis of cancer susceptibility, explore mechanisms to integrate this new knowledge into medical practice, and identify ways of addressing the associated psychosocial, ethical, legal, and public health issues.SUBJECTS AND METHODS:The CGN has developed the complex infrastructure required to support the projects, including the establishment of guidelines and policies, uniform methods, standard questionnaires to be used by all of the centers, and a standard format for submission of data to the Informatics Center. Cancer patients and their family members have been invited to enroll and be included in a pool of potential study participants. The Information Technology Group is responsible for support of the design, implementation, and maintenance of the multicenter Network-wide research protocols.RESULTS:As of January 2004, the CGN contained data on 23,995 probands (participants) and 425,798 family members. As a resource for cancer genetic studies, the CGN has a large number of probands and first-degree relatives with and without cancer and with multiple ethnicities. Different study designs can be used including case-control, case-case, and family studies.CONCLUSIONS:The unique resources of the CGN are available for studies on cancer genetic susceptibility, translational research, and behavioral research. The CGN is now at a point where approved collaborators may have access to enrolled patients and their families for special studies, as well as to the clinical, environmental and family cancer history data banked in the Informatics Center.
The recent completion of the first draft of the human genome sequence and advances in technologies for genomic analysis are generating tremendous opportunities for epidemiologic studies to evaluate the role of genetic variants in human disease. Many methodological issues apply to the investigation of variation in the frequency of allelic variants of human genes, of the possibility that these influence disease risk, and of assessment of the magnitude of the associated risk. Based on a Human Genome Epidemiology workshop, a checklist for reporting and appraising studies of genotype prevalence and studies of gene-disease associations was developed. This focuses on selection of study subjects, analytic validity of genotyping, population stratification, and statistical issues. Use of the checklist should facilitate the integration of evidence from these studies. The relation between the checklist and grading schemes that have been proposed for the evaluation of observational studies is discussed. Although the limitations of grading schemes are recognized, a robust approach is proposed. Other issues in the synthesis of evidence that are particularly relevant to studies of genotype prevalence and gene-disease association are discussed, notably identification of studies, publication bias, criteria for causal inference, and the appropriateness of quantitative synthesis.
Small farmers urgently need alternative marketing strategies if they are to achieve the goals of a more sustainable agriculture. This study was a survey of nine Pennsylvania wholesale produce auctions, all established between 1984 and 1998. The main goals of the auctions were to serve local communities, provide high-quality produce to local consumers and make profits. The results showed that the auctions typically employ an average of 7-10 people per growing season. The five most common commodities sold were cantaloupe, watermelon, tomato, pumpkin and sweet corn. Asparagus and onions were the least sold during a regular growing season. In terms of market share, roadside market operators purchased the largest proportion of produce (40%), followed by farmers (27%), chain food stores (16%), independent grocery stores (11%) and restaurants (6%), making up an average annual gross sale of $3.5 million per auction. The study revealed that the nine Pennsylvania produce auctions were successful in meeting their goals. The reasons for success included private ownership, excellent quality and freshness of produce, good location, local produce recognition, clientele availability and customer-oriented business. The auction managers identified some weaknesses, including inconsistent and poor grading, limited space in the auction facility, produce unavailability and limited volume, lack of cooling facility, price fluctuation and slow service. The study indicated that local wholesale produce auctions are a useful marketing alternative for small farmers in Pennsylvania, by providing marketing outlets and convenient shopping centers for sellers and buyers; by securing a source of fresh and locally grown produce not found in traditional wholesale terminal markets; and by allowing exchange and networking among farmers and buyers. Consequently, the wholesale produce auction can be a useful model for an alternative marketing strategy and can provide considerable benefits to small farm and rural communities.
In a statewide survey of 856 Iowa municipal drinking water supplies in 1986-1987 the Rathbun rural water system was found to contain elevated levels of triazine herbicides. Rates of low birth weight, prematurity, and intrauterine growth retardation (IUGR) in live singleton births during the period 1984-1990 by women living in 13 communities served by the Rathbun water system were compared to other communities of similar size in the same Iowa counties. The Rathbun communities had a greater risk of IUGR than southern Iowa communities with other surface sources of drinking water (relative risk = 1.8; 95% CI = 1.3, 2.7). Multiple linear regression analyses revealed that levels of the herbicides atrazine, metolachlor, and cyanzinc were each significant predictors of community IUGR rates in southern Iowa after controlling for several potentially confounding factors including maternal smoking and socioeconomic variables. The association with IUGR was strongest for atrazine, but all three herbicides were intercorrelated and the independent contributions of each to IUGR risk could not be determined. We conclude that communities in southern Iowa with drinking water supplies contaminated with herbicides have elevated rates of IUGR compared to neighboring communities with different water supplies. Because of the limitations of the ecologic design of this study, including aggregate rather than individual measures of exposure and limited ability to control for confounding factors related to source of drinking water and risk of IUGR, a strong causal relationship between any specific water contaminant and risk of IUGR cannot yet be inferred. The association between the water supplied to the Rathbun communities and the increased risk of IUGR should be considered a preliminary finding that needs to be verified by more detailed epidemiologic studies.
Maternal alcohol use during pregnancy is a known cause of birth defects associated with the fetal alcohol syndrome, but its role in more common, isolated, craniofacial birth defects is not well understood. A population-based, case-control study of orofacial clefts was conducted in Iowa using births during 1987-1991. Cases were identified by the Iowa Birth Defects Registry and classified as having a cleft lip with or without cleft palate (CLP) or cleft palate only (CP) and whether the cleft was isolated or occurred with other birth defects. Controls were selected from normal Iowa births. Maternal alcohol use during pregnancy was classified according to self-reported drinks consumed per month. Results are based on 302 controls and the following numbers in each case group: 118 isolated CLP, 56 isolated CP, 51 CLP with multiple defects, and 62 CP with multiple defects. Compared to women who did not drink alcohol during pregnancy, the relative odds of isolated CLP rose with increasing level of maternal drinking as follows: 1-3 drinks per months, 1.5; 4-10 drinks per month, 3.1; more than 10 drinks per month, 4.7 (chi-square test for trend, P = 0.003). Adjustment for maternal smoking, vitamin use, education, and household income did not substantially alter these results. No significant association was found between alcohol use and isolated cleft palate or clefts in children with multiple birth defects. Alcohol use during pregnancy may be a cause of isolated cleft lip with or without cleft palate.
Although ring chromosomes are observed in ahnost all autosomal groups in man, they are rare. We describe a male patient exldbiting cd du chat syndrome in which cytogenetic studies demonstrate he presonse of a ring chromosome 5. Deletion o£ the ring chromosome 5 is found between the p15 and q35 bands. Dental, medical and cytogenetic findings are compared to other ring chromosome 5 cases descMbed in literature.
A review of the literature on Ehlers-Danlos syndrome with particular attention to vascular complications enabled us to outline an orderly diagnostic and therapeutic plan which has allowed salvage of an individual with a popliteal false aneurysm. In patients with Ehlers-Danlos syndrome and brachial, superficial femoral, or popliteal arterial disruption, the use of proximal tourniquet control to allow ligation of the disrupted artery under a no-flow, no-pressure situation is recommended. The ligations should be carried out with a large ligature or possibly with large hemoclips and/or reinforced with multiple fine atraumatic vascular sutures distally. These patients may be treated successfully for flexion contractures because of the laxness of their tissues.
A generalization of the Pearson curves is obtained as the solution to the differential equation which best fits a histogram in the mean square and satisfies certain statistical constraints, e.g., the mean and variance may be prescribed. Φ is the theoretical distribution defined on the intervel is a rational function with numerator and denomenator orders of mand n, respevtively. The values of the coefficients in are obtained from a Powell minimization of the mean-square value plus sum-of-squares constraints. Excellent fits are obtained effciently which, furthermore, are capable of providing an analytical representation of an infinite tail. An accurate initial approximation of for starting the Powell minimization is obtained from a symbol manipulation code in PL/1—Formac and based on the visual decomposition of a histogram into sums of normal curves.
The receiver signal of a general angle tracking radar where there is asingle target which consists of a set of n reflectors is analyzed. It is shown how the analysis of this radar can be greatly simplified by representing the signals in the receiver as complex variables. This representation also makes it very easy to analyze such problems as scintillation and single-sideband crosstalk.