Team Projects And Peer Evaluations

The authors assign semester- or quarter-long team-based projects in several Computer Science and Finance courses. This paper reports on our experience in designing, managing, and evaluating such projects. In particular, we discuss the effects of team size and of various peer evaluation schemes on team performance and student learning. We report statistical measures of the students’ peer evaluations – do they always rate each other strongly or weakly? What are the means and ranges? More importantly, we discuss why we introduced these peer evaluations, and what effect they have had on student commitment and performance. We discuss a small number of cases where student participation was poor, and relate this to the peer evaluation process

Blood cadmium is elevated in iron deficient U.S. children: a cross-sectional study

Abstract Background Cadmium (Cd), a widespread environmental contaminant, and iron deficiency (ID), the most common nutrient deficiency in the world, are known risk factors for neurodevelopmental delays, as well as other disorders, in infants and children. Studies assessing the cumulative effects of these factors are lacking in children, despite concerns of increased uptake of metals in the presence of ID. Here we sought to determine if blood and urine Cd levels were elevated in ID children compared to non-ID children. Methods Data for 5224 children, aged 3–19 years, were obtained from the 1999–2002 NHANES. ID was defined as ≥2 of 3 abnormal iron indicators (low serum ferritin [SF], high free erythrocyte protoporphyrin [FEP], low % transferrin saturation [TSAT]); ID anemia (IDA) was defined as ID plus low hemoglobin (Hgb). Logistic regression was used to evaluate associations between ID, IDA, and abnormal iron indicators and categories of blood and urine Cd. Results Adjusted odds of ID, IDA, low SF, and low TSAT were associated with increasing category of blood Cd but not urine Cd. Adjusted ORs (95% CI) for blood Cd ≥0.5 μg/L versus < LOD were = 1.74 (1.30-2.34), 4.02 (1.92-8.41), 4.08 (2.36-5.89) and 1.78 (1.32-2.39), for ID, IDA, low SF, and low TSAT, respectively. Age and sex specific analyses of blood Cd and ID/abnormal iron indicators revealed that the observed associations were strongest in females aged 16–19 years. Conclusions Given their shared neurotoxic effects in children, and that many people live in areas with high burdens of both ID and Cd, more research into the complex relationships between nutrient deficiencies and environmental toxicants is vital.http://deepblue.lib.umich.edu/bitstream/2027.42/109497/1/12940_2013_Article_710.pd

Urinary Metabolites of Di(2‐ethylhexyl) Phthalate Are Associated With Decreased Steroid Hormone Levels in Adult Men

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96413/1/jandrol.108.006403.pd

Serum PCB levels and congener profiles among teachers in PCB-containing schools: a pilot study

<p>Abstract</p> <p>Background</p> <p>PCB contamination in the built environment may result from the release of PCBs from building materials. The significance of this contamination as a pathway of human exposure is not well-characterized, however. This research compared the serum PCB concentrations, and congener profiles between 18 teachers in PCB-containing schools and referent populations.</p> <p>Methods</p> <p>Blood samples from 18 teachers in PCB-containing schools were analyzed for 57 PCB congeners. Serum PCB concentrations and congener patterns were compared between the teachers, to the 2003-4 NHANES (National Health and Nutrition Examination Survey) data, and to data from 358 Greater Boston area men.</p> <p>Results</p> <p>Teachers at one school had higher levels of lighter (PCB 6-74) congeners compared to teachers from other schools. PCB congener 47 contributed substantially to these elevated levels. Older teachers (ages 50-64) from all schools had higher total (sum of 33 congeners) serum PCB concentrations than age-comparable NHANES reference values. Comparing the teachers to the referent population of men from the Greater Boston area (all under age 51), no difference in total serum PCB levels was observed between the referents and teachers up to 50 years age. However, the teachers had significantly elevated serum concentrations of lighter congeners (PCB 6-74). This difference was confirmed by comparing the congener-specific ratios between groups, and principal component analysis showed that the relative contribution of lighter congeners differed between the teachers and the referents.</p> <p>Conclusions</p> <p>These findings suggest that the teachers in the PCB-containing buildings had higher serum levels of lighter PCB congeners (PCB 6-74) than the referent populations. Examination of the patterns, as well as concentrations of individual PCB congeners in serum is essential to investigating the contributions from potential environmental sources of PCB exposure.</p

Manual synoptic climate classification for the East Coast of New England (USA) with an application to PM2.5 concentration

Version of RecordThis study presents a manual synoptic climate classification for the East Coast of New England with an application to regional pollution. New England weather was classified into 9 all-inclusive weather types: Canadian High, Modified High, Gulf of Maine Return, New England High, Atlantic Return, Frontal Atlantic Return, Frontal Overrunning-Continental, Frontal Overrun-ning-Marine, and Tropical Disturbance. Canadian High and Modified High weather are the domi-nant weather patterns at Boston, Massachusetts, while Tropical Disturbance, Gulf of Maine Return, and New England High weather types are the least frequent. Properties of the weather types were determined at 07:00 h Local Standard Time (LST) each day in Boston. The coldest and driest weather type is the Canadian High, while the hottest, most humid weather is generated by Frontal Atlantic Return. The synoptic weather classification system, applied to airborne fine particle mass concentra-tions with an aerodynamic diameter ≤2.5 μm (PM2.5), showed significant differences in concentra-tions between weather types: transport from the north and northwest had low PM2.5, while transport from the south and southwest had high PM2.5 concentrations. This climate classification system also has potential applications ranging from studies of insect migration to analyses of climate change.Keim, B. D., Meeker, L. D., & Slater, J. F. (2005). Manual synoptic climate classification for the East Coast of New England (USA) with an application to PM2.5 concentration. Climate Research, 28, 143-15

Urinary Metabolites of Organophosphate Flame Retardants: Temporal Variability and Correlations with House Dust Concentrations

Background: A reduction in the use of polybrominated diphenyl ethers (PBDEs) because of human health concerns may result in an increased use of and human exposure to organophosphate flame retardants (OPFRs). Human exposure and health studies of OPFRs are lacking. Objectives: We sought to define the degree of temporal variability in urinary OPFR metabolites in order to inform epidemiologic study design, and to explore a potential primary source of exposure by examining the relationship between OPFRs in house dust and their metabolites in urine. Methods: Nine repeated urine samples were collected from 7 men over the course of 3 months and analyzed for bis(1,3-dichloro-2-propyl) phosphate (BDCPP) and diphenyl phosphate (DPP), metabolites of the OPFRs tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and triphenyl phosphate (TPP), respectively. Intraclass correlation coefficients (ICCs) were calculated to characterize temporal reliability. Paired house dust and urine samples were collected from 45 men. Results: BDCPP was detected in 91% of urine samples, and DPP in 96%. Urinary BDCPP showed moderate-to-strong temporal reliability (ICC range, 0.55–0.72). ICCs for DPP were lower, but moderately reliable (range, 0.35–0.51). There was a weak [Spearman r (rS) = 0.31] but significant (p = 0.03) correlation between urinary BDCPP and TDCPP concentrations in house dust that strengthened when nondetects (rS = 0.47) were excluded. There was no correlation between uncorrected DPP and TPP measured in house dust (rS < 0.1). Conclusions: Household dust may be an important source of exposure to TDCPP but not TPP. Urinary concentrations of BDCPP and DPP were moderately to highly reliable within individuals over 3 months

Serum PCB levels and congener profiles among US construction workers

Abstract Background The presence of PCB in caulking (sealant) material found in masonry buildings has been well-documented in several countries. A recent investigation of 24 buildings in the greater Boston area found that 8 buildings had high PCB levels in caulking materials used around window frames and in joints between masonry blocks. Workers removing caulking material have been shown to have elevated serum PCB levels. Methods This project compared serum PCB levels among male workers who installed and/or removed PCB-containing caulking material from buildings in the greater Boston area with reference serum PCB levels from 358 men from the same area. Serum PCB levels were measured in the same laboratory by liquid-liquid extraction, column chromatography clean-up and dual capillary column GC/microECD analysis. Results When the congener profiles were compared between the reference population and the construction workers, the serum levels of the more volatile, lighter PCBs (di-, tri-and tetrachloro, sum of IUPAC# 6–74) were substantially higher among the construction workers. One of the youngest workers had the lowest total serum PCB levels (sum of 57 congeners) of all 6 workers, but the contribution of more volatile (less chlorinated) PCB congeners (#16, 26,28,33,74,66, and 60) was markedly higher than in other 5 workers and reference men. Only this worker was working on a job that involved removing PCB caulking at the time of the blood sampling. Conclusion While the results of this pilot study are based upon small numbers (6 construction workers who handled PCB caulking), the serum PCB levels among the construction workers exceed the referents. Comparison of the congener profiles suggests that there are substantial differences between the construction workers and the general population samples. These differences, and the similarities of profiles among the construction workers strongly suggest that occupational contact with caulking material can be a major source of PCB exposure for construction workers.http://deepblue.lib.umich.edu/bitstream/2027.42/117256/1/12940_2007_Article_124.pd

Selection of nonlinear interactions by a forward stepwise algorithm: Application to identifying environmental chemical mixtures affecting health outcomes

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149279/1/sim8059_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149279/2/SIM_8059-Supp-0001-InteractionSelection_Supp.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149279/3/sim8059.pd

Inflammatory and oxidative stress markers associated with decreased cervical length in pregnancy

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134275/1/aji12545_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134275/2/aji12545.pd