Multiple measures, such as multiple content domains or multiple types of performance, are used in various testing programs to classify examinees for screening or selection. Despite the popular usages ...of multiple measures, there is little research on classification consistency and accuracy of multiple measures. Accordingly, this study introduces an approach to estimate classification consistency and accuracy indices for multiple measures under four possible decision rules: (1) complementary, (2) conjunctive, (3) compensatory, and (4) pairwise combinations of the three. The current study uses the IRT‐recursive‐based approach with the simple‐structure multidimensional IRT model (SS‐MIRT) to estimate the classification consistency and accuracy for multiple measures. Theoretical formulations of the four decision rules with a binary decision (Pass/Fail) are presented. The estimation procedures are illustrated using an empirical data example based on SS‐MIRT. In addition, this study applies the estimation procedures to the unidimensional IRT (UIRT) context, considering that UIRT is practically used more. This application shows that the proposed procedure of classification consistency and accuracy could be used with a UIRT model for individual measures as an alternative method of SS‐MIRT.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The current study proposed several variants of simple‐structure multidimensional item response theory equating procedures. Four distinct sets of data were used to demonstrate feasibility of proposed ...equating methods for two different equating designs: a random groups design and a common‐item nonequivalent groups design. Findings indicated some notable differences between the multidimensional and unidimensional approaches when data exhibited evidence for multidimensionality. In addition, some of the proposed methods were successful in providing equating results for both section‐level and composite‐level scores, which has not been achieved by most of the existing methodologies. The traditional method of using a set of quadrature points and weights for equating turned out to be computationally intensive, particularly for the data with higher dimensions. The study suggested an alternative way of using the Monte‐Carlo approach for such data. This study also proposed a simple‐structure true‐score equating procedure that does not rely on a multivariate observed‐score distribution.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Background:A high level of apolipoprotein B (apoB) is associated with incident coronary artery disease (CAD) when low-density lipoprotein cholesterol (LDL-C) level is discordantly low or concordantly ...high. However, data on the relationship of apoB with subclinical measure of CAD are limited.Methods and Results:A total of 14,205 men (mean age 41.0 years) who were free of cardiovascular disease at baseline and who underwent a health checkup exam, including measurement of coronary artery calcium (CAC), were studied. Of the study group, 2,773 participants (19.5%) had CAC at baseline, and CAC progression was observed in 2,550 (18.0%). The multivariate-adjusted CAC score ratios (95% confidence interval) comparing discordantly high apoB/low LDL-C and concordantly high apoB/high LDL-C with concordantly low apoB/low LDL-C were 1.51 (0.98–2.32) and 2.70 (2.19–3.33), respectively. The corresponding relative risks for CAC progression were 1.26 (1.02–1.56) and 1.49 (1.34–1.66), respectively. These associations did not change appreciably after adjustment for insulin resistance and subclinical inflammation.Conclusions:Discordant analysis showed that a high apoB level was strongly associated with prevalence and progression of CAC independent of LDL-C in a large cohort of healthy adults. The present study results highlighted the importance of an apoB measure as a potential target for primary prevention of coronary atherosclerosis in healthy adults.
When sufficient time-series images and training data are unavailable for crop classification, features extracted from convolutional neural network (CNN)-based representative learning may not provide ...useful information to discriminate crops with similar spectral characteristics, leading to poor classification accuracy. In particular, limited input data are the main obstacles to obtain reliable classification results for early crop mapping. This study investigates the potential of a hybrid classification approach, i.e., CNN-random forest (CNN-RF), in the context of early crop mapping, that combines the automatic feature extraction capability of CNN with the superior discrimination capability of an RF classifier. Two experiments on incremental crop classification with unmanned aerial vehicle images were conducted to compare the performance of CNN-RF with that of CNN and RF with respect to the length of the time-series and training data sizes. When sufficient time-series images and training data were used for the classification, the accuracy of CNN-RF was slightly higher or comparable with that of CNN. In contrast, when fewer images and the smallest training data were used at the early crop growth stage, CNN-RF was substantially beneficial and the overall accuracy increased by maximum 6.7%p and 4.6%p in the two study areas, respectively, compared to CNN. This is attributed to its ability to discriminate crops from features with insufficient information using a more sophisticated classifier. The experimental results demonstrate that CNN-RF is an effective classifier for early crop mapping when only limited input images and training samples are available.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The purpose of this study was to compare calibration and linking methods for placing pretest item parameter estimates on the item pool scale in a 1‐3 computerized multistage adaptive testing design ...in terms of item parameter recovery. Two models were used: embedded‐section, in which pretest items were administered within a separate module, and embedded‐items, in which pretest items were distributed across operational modules. The calibration methods were separate calibration with linking (SC) and fixed calibration (FC) with three parallel approaches under each (FC‐1 and SC‐1; FC‐2 and SC‐2; and FC‐3 and SC‐3). The FC‐1 and SC‐1 used only operational items in the routing module to link pretest items. The FC‐2 and SC‐2 also used only operational items in the routing module for linking, but in addition, the operational items in second stage modules were freely estimated. The FC‐3 and SC‐3 used operational items in all modules to link pretest items. The third calibration approach (i.e., FC‐3 and SC‐3) yielded the best results. For all three approaches, SC outperformed FC in all study conditions which were module length, sample size and examinee distributions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Carotenoids are essential for plant and animal nutrition, and are important factors in the variation of pigmentation in fruits, leaves, and flowers. Tomato is a model crop for studying the biology ...and biotechnology of fleshy fruits, particularly for understanding carotenoid biosynthesis. In commercial tomato cultivars and germplasms, visual phenotyping of the colors of ripe fruits can be done easily. However, subsequent analysis of metabolic profiling is necessary for hypothesizing genetic factors prior to performing time-consuming genetic analysis. We used high performance liquid chromatography (HPLC), employing a C
reverse-phase column, to efficiently resolve nine carotenoids and isomers of several carotenoids in yellow, orange, and red colored ripe tomatoes. High content of lycopene was detected in red tomatoes. The orange tomatoes contained three dominant carotenoids, namely δ-carotene, β-carotene, and prolycopene. The yellow tomatoes showed low levels of carotenoids compared to red or orange tomatoes. Based on the HPLC profiles, genes responsible for overproducing δ-carotene and prolycopene were described as
and
, respectively. Subsequent genetic analysis using DNA markers for segregating population and germplasms were conducted to confirm the hypothesis. This study establishes the usefulness of metabolic profiling for inferring the genetic determinants of fruit color.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Summary
Three‐dimensional printing (3DP), a novel food‐processing technique, may improve the aesthetic qualities of insect‐based products. In this study, structural and morphological properties of ...insect powder‐based bio‐inks with 0%–75% insect powder (IP) in wheat flour (WF) matrix were evaluated. Proximate composition, water absorption capacity, amino acids and degree of redness and yellowness increased (P < 0.05). Fourier transform infrared analysis, scanning electron microscope and 3D printability results showed good incorporation of IP and WF. Good viscoelastic properties were exhibited by the inks using 40% solid of 75% IP and 25% WF, and 50% solid of 50% IP and 50% WF. These samples showed comparable dimensions to the standard design and had good textural properties. Thus, 3DP can be effective in processing edible insects, improving the aesthetic quality and reducing consumer apathy.
Three‐dimensional printing of Acheta domesticus.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The current study aims to evaluate the performance of three non‐IRT procedures (i.e., normal approximation, Livingston‐Lewis, and compound multinomial) for estimating classification indices when the ...observed score distribution shows atypical patterns: (a) bimodality, (b) structural (i.e., systematic) bumpiness, or (c) structural zeros (i.e., no frequencies). Under a bimodal distribution, the normal approximation procedure produced substantially large bias. For a distribution with structural bumpiness, the compound multinomial procedure tended to introduce larger bias. Under a distribution with structural zeroes, the relative performance of selected estimation procedures depended on cut score location and the sample‐size conditions. In general, the differences in estimation errors among the three procedures were not substantially large.
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Siloxanes are widely used in various industrial applications as well as in personal care products. Despite their widespread use and potential toxic effects, few studies have reported on the ...occurrence of siloxanes in the environment. In this study, we determined the concentrations of 5 cyclic and 15 linear siloxanes in sludge collected from 40 representative wastewater treatment plants (WWTPs) in Korea. Total concentrations of 20 siloxanes (Σsiloxane) in sludge ranged from 0.05 to 142 (mean: 45.7) μg/g dry weight, similar to the concentrations reported in European countries but higher than those reported in China. The concentrations of siloxanes in sludge from domestic WWTPs were significantly (p<0.01) higher than those from industrial WWTPs, indicating higher consumption of siloxanes in various personal care products (e.g. shampoos and conditioners). The major siloxane compounds found in sludge were decamethylcyclopentasilane (D5), docosamethyldecasiloxane (L10) and dodecamethylcyclohexasilane (D6), which collectively accounted for, on average, 62% of the Σsiloxane concentrations. Non-parametric multidimensional scaling ordination of the profiles of siloxanes indicated the existence of different usage patterns of siloxanes between industrial and household activities. Multiple linear regression analysis of siloxane concentrations and WWTP characteristics suggested that D5, D6 and linear siloxane concentrations in sludge were positively correlated with population served by a WWTP. Environmental emission fluxes of cyclic and linear siloxanes through sludge disposal in Korea were 14,800 and 18,500kg/year, respectively. This is the first report describing occurrence and environmental emission of siloxanes through sludge in Korea.
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•Highest levels of siloxanes were found in domestic WWTP sludge from Korea.•Compositional profiles of siloxanes varied domestic and industrial WWTP sludge.•The nationwide emission flux of siloxanes via sludge discharge was estimated.•Population-served is a determinant of siloxanes in sludge from WWTPs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
To assess the aquaculture-induced sediment conditions associated with sulfur cycles, shifts in bacterial communities across farming stages were investigated. The sulfate reduction rate (SRR), and ...concentrations of acid volatile sulfide (AVS) and H2S were significantly higher at the mid- and post-farming stages than at the early stage, indicating that the aquaculture effects persist even after harvest. Incomplete organic carbon–oxidizing sulfate-reducing bacteria (IO-SRB) affiliated with Desulfobulbaceae, and gammaproteobacterial sulfur oxidizing bacteria (SOB) (Thiohalobacter, Thioprofundum, and Thiohalomonas) were dominant during the early stage, whereas fermenting bacteria (Bacteroidetes and Firmicutes) and complete oxidizing SRB (CO-SRB) belonging to Desulfobacteraceae, and epsilonproteobacterial SOB (Sulfurovum) dominated during the mid- and post-stages. The shift in SRB and SOB communities well reflected the anoxic and sulfidic conditions of farm sediment. Especially, the Sulfurovum-like SOB correlated highly and positively with H2S, AVS, and SRR, suggesting that they could be relevant microbiological proxies to assess sulfidic conditions in farm sediment.
•Intense aquaculture activities resulted in highly sulfidic and anoxic sediment conditions.•Shifts in benthic bacterial communities occur with the farming stages.•Fermenters and Desulfobacteraceae predominated under extremely anoxic conditions.•Sulfurovum significantly increased in highly sulfidic condition.•Sulfurovum could be used as a proxy to assess sulfidic conditions of the farm sediment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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