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To achieve the measurement reliability of amino acids used as diagnostic markers in clinical fields, establishing a reference measurement system is required, in which certified reference materials (CRMs) are an essential step in the hierarchy of measurement traceability. This study describes the development of dried blood spot (DBS) CRMs for amino acid analysis with complete measurement traceability to the International System of Units (SI). Six essential amino acids─proline, valine, isoleucine, leucine, phenylalanine, and tyrosine─were analyzed using isotope-dilution liquid chromatography-mass spectrometry (ID-MS). For minimizing measurement bias and uncertainty overestimation, whole spots with 50 μL of whole blood were adopted in the certification. The between-spot homogeneities by whole spot sampling were lower than 2.1%. The relative expanded uncertainties of the six amino acids in the developed DBS CRMs were lower than 5.7% at 95% confidence. The certified values are traceable to SI through both gravimetric preparation and the primary method in certification, ID-MS. Comparison among DBS testing laboratories revealed discrepancies between the whole spot and disc sampling methods. The actual sampling volume was accurately estimated by weighing, which revealed the possibility of underestimation in routine DBS testing. The candidate CRMs can support the standardization of DBS testing for amino acids through the qualification and validation of many kinds of measurement procedures to compensate the measurement bias caused by matrix-specific sampling error.

The Child Behavior Checklist (CBCL) and Strengths and Difficulties Questionnaire (SDQ) both measure emotional and behavioral problems in children and adolescents, and scores on the two instruments are highly correlated. When administrative needs compel practitioners to change the instrument used or data from the two measures are combined to perform pooled analyses, it becomes necessary to compare scores on the two instruments. To enable such comparisons, we score linked three domains (Internalizing, Externalizing, and Total Problems) of the CBCL and SDQ in three age groups spanning 2-17 years. After assessing linking assumptions, we compared item response theory (IRT) and equipercentile linking methods to identify the most statistically justifiable link, ultimately selecting equipercentile linking with loglinear smoothing due to its minimal bias and the ability to link raw SDQ scores with both T-scores and raw scores from the CBCL. We derived crosswalk conversion tables to convert scores on one measure to the metric of the other and discuss the use of these tables in research and practice. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Fine particulate matter (PM(2.5)) is a well-established risk factor for public health. To support both health risk assessment and epidemiological studies, data are needed on spatial and temporal patterns of PM(2.5) exposures. This review article surveys publicly available exposure datasets for surface PM(2.5) mass concentrations over the contiguous U.S., summarizes their applications and limitations, and provides suggestions on future research needs. The complex landscape of satellite instruments, model capabilities, monitor networks, and data synthesis methods offers opportunities for research development, but would benefit from guidance for new users. Guidance is provided to access publicly available PM(2.5) datasets, to explain and compare different approaches for dataset generation, and to identify sources of uncertainties associated with various types of datasets. Three main sources used to create PM(2.5) exposure data are: ground-based measurements (especially regulatory monitoring), satellite retrievals (especially aerosol optical depth, AOD), and atmospheric chemistry models. We find inconsistencies among several publicly available PM(2.5) estimates, highlighting uncertainties in the exposure datasets that are often overlooked in health effects analyses. Major differences among PM(2.5) estimates emerge from the choice of data (ground-based, satellite, and/or model), the spatiotemporal resolutions, and the algorithms used to fuse data sources.

This research suggests emphasis manipulation on constituent skills of least-abled sets, improves coordination and integration of knowledge, skills, and attitudes on cognitive load, transfer, and instructional efficiency. The participants were divided into two groups. Competency levels for the designated skill sets were evaluated, and a pre-test was performed on both groups. The research applied an educational design based on individual learner’s least-abled sets of constituent skills and identified the design’s effectiveness on complex learning. One group was provided with the whole learning contents according to emphasis manipulation sequencing method, and the other group was provided personalized learning contents according to a method based on the least-abled sets of constituent skills emphasis manipulation. The group received materials constructed with emphasis manipulation, learned the whole constituent skills of learning contents and carried out conventional tasks. However, treatment group received materials constructed with the least-abled sets of constituent skills emphasis manipulation, learned only the least-abled constituent skills and carried out conventional tasks. This research suggests that teaching with the least-abled sets of constituent skills helps to reduce expertise-reversal effect and improve results of cognitive load, transfer and instructional efficiency. Keywords: cognitive load, complex tasks, emphasis manipulation, instructional efficiency, learning transfer.

During early viral infection, activation of natural killer (NK) cells elicits the effector functions of target cell lysis and cytokine production. However, the cellular and molecular mechanisms leading to NK cell activation during viral infections are incompletely understood. In this study, using a model of acute viral infection, we investigated the mechanisms controlling cytotoxic activity and cytokine production in response to influenza (flu) virus. Analysis of cytokine receptor deficient mice demonstrated that type I interferons (IFNs), but not IL-12 or IL-18, were critical for the NK cell expression of both IFN-γ and granzyme B in response to flu infection. Further, adoptive transfer experiments revealed that NK cell activation was mediated by type I IFNs acting directly on NK cells. Analysis of signal transduction molecules showed that during flu infection, STAT1 activation in NK cells was completely dependent on direct type I IFN signaling, whereas STAT4 activation was only partially dependent. In addition, granzyme B induction in NK cells was mediated by signaling primarily through STAT1, but not STAT4, while IFN-γ production was mediated by signaling through STAT4, but not STAT1. Therefore, our findings demonstrate the importance of direct action of type I IFNs on NK cells to mount effective NK cell responses in the context of flu infection and delineate NK cell signaling pathways responsible for controlling cytotoxic activity and cytokine production.