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A robust isotope-labeled internal standard method was established for the detection of 22 pesticides and metabolite residues in four kinds of fish; two were from freshwater fish, and two were from marine fish. Pesticides with wide application possibilities in rice in China, strong leaching to water, or high bioconcentration factors (BCF) in fish were selected. The samples were extracted with 1% acetic acid-99% acetonitrile. The extracts were first purified by solid-phase extraction (PEP-plus), cleaned with dispersive-solid-phase extraction (PSA and C18), and finally analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The results showed that good linearities for the target compounds were observed in the range of 0.1-100 ng/mL, and the correlation coefficient (R2) of each compound was greater than 0.99. The recoveries of the method were within 70-120% with RSDs

Background: The Nutrition and Physical activity Self-Assessment in Child Care (Go NAP SACC) is an evidence-based intervention developed to positively impact childhood obesity in early childhood education (ECE) facilities. One focus of Go NAP SACC is the development of physical activity best practices. However, little research has examined differences in achievement of best practices based on age of child and geographic location. Purpose: To examine differences in the achievement of physical activity best practices between urban and rural childcare facilities by age-specific recommendations (infants, toddlers, and preschoolers) and in the overall physical activity environment. Urban (n=207) and rural (n=218) ECE facilities completed the Go NAP SACC process. Scores of the post intervention self- assessment were used for comparison. Data were analyzed using an ANCOVA. Results: A majority of facilities reported exceeding best practices (79.5%). Of the 45 items assessed, significant differences were found for 18 best practices with urban facilities outscoring their rural counterparts on 17 of these items. A comparison by age found that urban facilities reported higher achievement of best practices among infants (60%) in comparison to toddlers (40%) or preschoolers (30%). Discussion: Urban ECE facilities scored significantly higher than their rural counterparts on 40% of the items assessed. Thus, there is a need to develop and identify relevant resources for continued improvement of best practices based on geographical location. Future studies should continue to explore the rural-urban context of physical activity practices across the early childhood age groups to ensure healthy physical development of children. Funding: This project was supported by the Cooperative Agreement Number NU58DP004819, funded by the Centers for Disease Control and Prevention. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Prevention or the Department of Health and Human Services. This work was also supported by a Nebraska Department of Health and Human Services Child Care and Development Fund, USDA Nebraska Team Nutrition, and a Title V Maternal and Child Health Block Grant., The Health & Fitness Journal of Canada, Vol. 14 No. 3 (2021): Proceedings from the 8th International Society for Physical Activity and Health Congress

Although dicofol has been widely banned all over the world as a kind of organochlorine contaminant, it still exists in the environment. This study developed a high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS) detection technique for dicofol, an environmental pollutant, for the first time using in-source fragmentation. The results confirmed that m/z 251 was the only precursor ion of dicofol after in-source fragmentation, and m/z 139 and m/z 111 were reasonable product ions. The main factors triggering the in-source fragmentation were the H+ content and solution conductivity when dicofol entered the mass spectrometer. Density functional theory can be used to analyze and interpret the mechanism of dicofol fragmentation reaction in ESI source. Dicofol reduced the molecular energy from 8.8 ± 0.05 kcal/mol to 1.0 ± 0.05 kcal/mol, indicating that the internal energy release from high to low was the key driving force of in-source fragmentation. A method based on HPLC-MS/MS was developed to analyze dicofol residues in environmental water. The LOQ was 0.1 μg/L, which was better than the previous GC or GC-MS methods. This study not only proposed an HPLC-MS/MS analysis method for dicofol for the first time but also explained the in-source fragmentation mechanism of compounds in ESI source, which has positive significance for the study of compounds with unconventional mass spectrometry behavior in the field of organic pollutant analysis and metabonomics.

The Selective catalytic reduction (SCR) technology is an effective and economical method for reducing NOx emissions from the heavy duty diesel engine. To ensure a reasonable design of the SCR system, it is critical to understand the effects of space velocity (GHSV), NO2/NOx ratio, NH3/NOx ratio and structural parameters of the SCR reactor on the NOx conversion efficiency. Using the experimental method to conduct all the investigations though the entire development cycle of SCR system is expensive and would cost a long time. Numerical method as a complementary tool to bench tests can help to optimize the design and shorten the development cycle of SCR system. In this paper, a mathematical model is developed to predict the NOx conversion efficiency over a Cu catalyst. The model is calculated in the MATLAB environment. The simulation results agree well with the experimental data, which indicates that the mathematical model is reliable and can effectively predict the performance of the SCR catalytic system. Then the effects of the parameters, such as space velocity, NO2/NOx ratio, NH3/NOx ratio, length, diameter and number of channels per square inch (CPSI) of the SCR reactor on the NOx conversion efficiency were studied.

The bulk current injection with substitution method is applied to the electromagnetic compatibility (EMC) test of automotive components. In this paper, the experimental characteristics of the device under test (DUT) with differential- mode bulk current injection and common-mode bulk current injection are studied. Also, the effects of the location of the bulk current injection probe are studied briefly. The test setup is in compliance with the ISO 11452-4 standard and the applicable frequency range is 1 MHz to 400 MHz. The results show that, due to the resonance phenomenon, the current coupled into the wiring harness in the common-mode bulk current injection test is sometimes less than the current coupled into the wiring harness in the differential-mode bulk current injection test. Moreover, the current coupled into the wiring harness is related to the location of the current injection probe, and the effects of the location are different in different frequency bands. However, in the ISO11452-4 standard, only common-mode bulk current injection test is considered in the bulk current injection immunity test. Therefore, in order to accurately reflect the true immunity level of the DUT, the differential-mode bulk current injection test should be considered in the ISO 11452-4 standard.

The purpose of this study was to examine the physical activity environment in childcare programs across type (childcare centers [CCCs] and family childcare homes [FCCHs]) and geographic location (urban and rural) as assessed by physical activity best practices according to the Go Nutrition and Physical Activity Self-assessment in Child Care. Results showed CCCs compared with FCCHs reported higher achievement of best practices. Further, urban childcare programs (CCCs and FCCHs) reported higher achievement of best practices in comparison to rural childcare programs. There is a need to deliver targeted interventions that promote children's physical activity in FCCHs and CCCs in rural areas.

A numerical model of spray and its interaction with the gas exhaust flow and static mixer are developed to investigate the effects of the mixer on the selective catalytic reduction (SCR). The residence time of spray droplets in straight pipes with and without mixers and the interaction between spray droplets and the blades of mixers are investigated. The numerical results show that due to the improvement of evaporation rates of sprays and the ability to break droplets into smaller ones, static mixers can help SCR systems achieve better urea conversion efficiency. Furthermore, the using of mixers significantly improves the uniformity of the reducing agent in a pipe.

Background SNPs are informative to estimate genomic breed composition (GBC) of individual animals, but selected SNPs for this purpose were not made available in the commercial bovine SNP chips prior to the present study. The primary objective of the present study was to select five common SNP panels for estimating GBC of individual animals initially involving 10 cattle breeds (two dairy breeds and eight beef breeds). The performance of the five common SNP panels was evaluated based on admixture model and linear regression model, respectively. Finally, the downstream implication of GBC on genomic prediction accuracies was investigated and discussed in a Santa Gertrudis cattle population. Results There were 15,708 common SNPs across five currently-available commercial bovine SNP chips. From this set, four subsets (1,000, 3,000, 5,000, and 10,000 SNPs) were selected by maximizing average Euclidean distance (AED) of SNP allelic frequencies among the ten cattle breeds. For 198 animals presented as Akaushi, estimated GBC of the Akaushi breed (GBCA) based on the admixture model agreed very well among the five SNP panels, identifying 166 animals with GBCA = 1. Using the same SNP panels, the linear regression approach reported fewer animals with GBCA = 1. Nevertheless, estimated GBCA using both models were highly correlated (r = 0.953 to 0.992). In the genomic prediction of a Santa Gertrudis population (and crosses), the results showed that the predictability of molecular breeding values using SNP effects obtained from 1,225 animals with no less than 0.90 GBC of Santa Gertrudis (GBCSG) decreased on crossbred animals with lower GBCSG. Conclusions Of the two statistical models used to compute GBC, the admixture model gave more consistent results among the five selected SNP panels than the linear regression model. The availability of these common SNP panels facilitates identification and estimation of breed compositions using currently-available bovine SNP chips. In view of utility, the 1 K panel is the most cost effective and it is convenient to be included as add-on content in future development of bovine SNP chips, whereas the 10 K and 16 K SNP panels can be more resourceful if used independently for imputation to intermediate or high-density genotypes. Electronic supplementary material The online version of this article (10.1186/s12863-018-0654-3) contains supplementary material, which is available to authorized users.

Background: The purpose of this study was to determine if the Go Nutrition and Physical Activity Self-Assessment in Child Care (Go NAP SACC) intervention was effective in improving best practices in the areas of infant and child physical activity and outdoor play and learning in family child care homes (FCCHs) in Nebraska.Methods: FCCHs (n = 201) participated in a pre–post evaluation using the Infant and Child Physical Activity and Outdoor Play and Learning assessments from the Go NAP SACC validated measure to assess compliance with best practices.Results: At post, FCCHs demonstrated significant differences in 85% of the Infant and Child Physical Activity items (17 of 20) and 80% of the Outdoor Play and Learning items (12 of 15). Significant differences in best practices between urban and rural FCCH providers were also found.Conclusion: Go NAP SACC appears to be an effective intervention in Nebraska as, after participation in the initiative, providers were improving child care physical activity best practices. Additional research is needed to objectively determine if these changes resulted in objective improvements in children’s physical activity levels. Further, efforts are needed to develop and/or identify geographic-specific resources for continued improvement.

Figure S3. Plot of -2logLikelihood values computed for 198 purported Akaushi cattle, based on the admixture model with 1Â K versus 16Â K SNP panels. (DOCX 25 kb)

Table S1. Correlations of -2logLikelihood values computed for 198 purported Akaushi cattle using the five SNP panels. Table S2. Genomic breed characterization of 198 purported Akaushi animals based on the admixture model using each of the five SNP panels. Table S3. Genomic breed characterization of 1424 purported Santa Gertrudis cattle based on the admixture model using the 1Â K SNP panel. (DOCX 251 kb)

Figure S6. Plots of -2logLikelihood for 291 Santa Gertrudis cattle after removing outliers. The likelihood values were computed assuming the true allele frequencies of SNPs were equal to those of each of the 10 breeds, respectively. The assumed breeds (from right to left) are Santa Gertrudis, Beef Master, Brangus, Red Angus, Angus, Hereford, Holstein, Wagyu, Akaushi, and Jersey. (DOCX 39 kb)

Figure S5. Plots of -2logLikelihood for 583 BeefMaster cattle after removing outliers. The likelihood values were computed assuming the true allele frequencies of SNPs were equal to those of each of the 10 breeds, respectively. The assumed breeds (from right to left) are Beef Master, Santa Gertrudis, Brangus, Hereford, Angus, Red Angus, Holstein, Jersey, Wagyu, and Akaushi. (DOCX 39 kb)

Figure S4. Plots of -2logLikelihood for 1770 reference Brangus animals (green circles) after removing outliers. The likelihood values were computed assuming the true allele frequencies of SNPs were equal to those of each of the 10 breeds, respectively. The assumed breeds (from left to right) are Brangus, Angus, Red Angus, Santa Gertrudis, Beef Master, Hereford, Holstein, Jersey, Wagyu, and Akaushi. (DOCX 37 kb)

Table S1. Correlations of -2logLikelihood values computed for 198 purported Akaushi cattle using the five SNP panels. Table S2. Genomic breed characterization of 198 purported Akaushi animals based on the admixture model using each of the five SNP panels. Table S3. Genomic breed characterization of 1424 purported Santa Gertrudis cattle based on the admixture model using the 1Â K SNP panel. (DOCX 251 kb)

Figure S4. Plots of -2logLikelihood for 1770 reference Brangus animals (green circles) after removing outliers. The likelihood values were computed assuming the true allele frequencies of SNPs were equal to those of each of the 10 breeds, respectively. The assumed breeds (from left to right) are Brangus, Angus, Red Angus, Santa Gertrudis, Beef Master, Hereford, Holstein, Jersey, Wagyu, and Akaushi. (DOCX 37 kb)

Figure S1. Density plot of genomic breed composition of 1424 animals putatively presented as Santa Gertrudis cattle. (DOCX 23 kb)

Figure S2. Map view of 1 K (A), 3 K (B), 5 K (C), 10 K (D) and 16 K (E) SNP panels, where 1 K, 3 K, 5 K and 10 L denotes 1000, 3000, 5000 and 10,000 SNP panels, respectively. The 1-10 K panels were obtained by maximizing average Euclidean distance of SNP allele frequencies among ten cattle breeds. The 16 K consisted of 15,708 common SNPs across five currently used bovine SNP chips. (DOCX 290 kb)

Figure S2. Map view of 1 K (A), 3 K (B), 5 K (C), 10 K (D) and 16 K (E) SNP panels, where 1 K, 3 K, 5 K and 10 L denotes 1000, 3000, 5000 and 10,000 SNP panels, respectively. The 1-10 K panels were obtained by maximizing average Euclidean distance of SNP allele frequencies among ten cattle breeds. The 16 K consisted of 15,708 common SNPs across five currently used bovine SNP chips. (DOCX 290 kb)

Figure S5. Plots of -2logLikelihood for 583 BeefMaster cattle after removing outliers. The likelihood values were computed assuming the true allele frequencies of SNPs were equal to those of each of the 10 breeds, respectively. The assumed breeds (from right to left) are Beef Master, Santa Gertrudis, Brangus, Hereford, Angus, Red Angus, Holstein, Jersey, Wagyu, and Akaushi. (DOCX 39 kb)

Figure S6. Plots of -2logLikelihood for 291 Santa Gertrudis cattle after removing outliers. The likelihood values were computed assuming the true allele frequencies of SNPs were equal to those of each of the 10 breeds, respectively. The assumed breeds (from right to left) are Santa Gertrudis, Beef Master, Brangus, Red Angus, Angus, Hereford, Holstein, Wagyu, Akaushi, and Jersey. (DOCX 39 kb)