Arguments about using computer facilities in classroom teaching have received a lot of attention over time. Using the computer facilities will be helpful to demonstrate real-world applications, while poor data or inappropriate case studies might hinder the applications of the computer programs in classroom teaching. In this paper, we examine the impacts that using computer programs to teach business statistics have on students in the Krannert School of Management at Purdue University. The results show that students are attracted to the interactive computer programs designed for the business statistics course, and students are more motivated to attend classes when computer programs are applied in teaching. Furthermore, computer programs help students to understand confusing topics, and students feel that teaching them to use computer facilities really improves their own abilities to apply similar programs in analyzing real-world problems.

The main safety issue of cereal grains is mycotoxin contamination. There is no published information about mycotoxin contamination of organic wheat in the United States. This study quantified the contents of deoxynivalenol (DON) and ochratoxin A (OTA), two frequently occurring mycotoxins, in organic wheat samples collected from six counties in North Carolina by enzyme‐linked immunosorbent assay (ELISA) and high‐performance liquid chromatography (HPLC). By ELISA, all samples were DON and OTA positive, and the DON contents in the flour and bran samples were 0.7–2.35 ppm and 5–8 ppm, respectively, while OTA in the flour and bran samples were 9.54–25.55 ppb and 21.67–32.55 ppb, respectively. By HPLC, the DON detected in flour and bran were 0.24–0.47 ppm and 0.35–0.83 ppm, respectively; all flour samples were OTA negative, but 5 out of 6 bran samples were OTA positive (0.48–1.28 ppb). More studies with larger sample number are needed to obtain representative results. Practical applications This study provides preliminary results about the DON and OTA in organic wheat grains. The results indicate that the organic wheat produced in North Carolina during 2018 season were contaminated by DON and OTA to various degrees. However, the concentrations of these two mycotoxins determined by ELISA were significantly higher than those determined by HPLC. Therefore, to avoid overestimation or underestimation, it is important for researchers and regulatory agencies to conduct multi‐lab studies to develop and standardize analytical methods and detailed procedures for accurate DON and OTA quantification. Regardless of analytical methods, all bran samples showed higher DON and OTA concentrations than flour samples. Thus, when using organic wheat bran or whole wheat as food or feed ingredients, the level of bran inclusion should be controlled to protect consumers and animals from mycotoxicosis.

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Application of crop residues and biochar have been demonstrated to improve soil biological and chemical properties in agroecosystems. However, the integrated effect of organic amendments and hydrological cycles on soil health indicators are not well understood. In this study, we quantified the impact of hemp residue (HR), hemp biochar (HB), and hardwood biochar (HA) on five hydrolytic enzymes, soil microbial phospholipid (PLFA) community structure, pH, permanganate oxidizable carbon (POXC) soil organic carbon (SOC), and total nitrogen (TN). We compared two soil types, Piedmont and Coastal Plain soils of North Carolina, under (i) a 30-d moisture cycle maintained at 60% water-filled pore space (WFPS) (D-W1), followed by (ii) a 7-day alternate dry-wet cycle for 42 days (D-W2), or (iii) maintained at 60% WFPS for 42 days (D-W3) during an aerobic laboratory incubation. Results showed that HR and HB significantly increased the geometric mean enzyme activity by 1-2-fold in the Piedmont soil under the three moisture cycles and about 1.5-fold under D-W in the Coastal soil. In the presence of HA, the measured soil enzyme activities were significantly lower than control under the moisture cycles in both soil types. The shift in microbial community structure was distinct in the Coastal soil but not in the Piedmont soil. Under D-W2, HR and HB significantly increased POXC (600–700 mg POXC kg-1 soil) in the Coastal soil but not in the Piedmont soil while HA increased nitrate (8 mg kg-1) retention in the Coastal soil. The differences in amendment effect on pH SOC, TN, POXC, and nitrate were less distinct in the fine-textured Piedmont soil than the coarse-textured Coastal soil. Overall, the results indicate that, unlike HA, HR and HB will have beneficial effects on soil health and productivity, therefore potentially improving soil’s resilience to changing climate.