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Plant pathogens cause devastating diseases, leading to serious losses to agriculture. Mechanistic understanding of pathogenesis of plant pathogens lays the foundation for the development of fungicides for disease control. Mitophagy, a specific form of autophagy, is important for fungal virulence. The role of cardiolipin, mitochondrial signature phospholipid, in mitophagy and pathogenesis is largely unknown in plant pathogenic fungi. The functions of enzymes involved in cardiolipin biosynthesis and relevant inhibitors were assessed using a set of assays, including genetic deletion, plant infection, lipidomics, chemical‐protein interaction, chemical inhibition, and field trials. Our results showed that the cardiolipin biosynthesis‐related gene MoGEP4 of the rice blast fungus Magnaporthe oryzae regulates growth, conidiation, cardiolipin biosynthesis, and virulence. Mechanistically, MoGep4 regulated mitophagy and Mps1‐MAPK phosphorylation, which are required for virulence. Chemical alexidine dihydrochloride (AXD) inhibited the enzyme activity of MoGep4, cardiolipin biosynthesis and mitophagy. Importantly, AXD efficiently inhibited the growth of 10 plant pathogens and controlled rice blast and Fusarium head blight in the field. Our study demonstrated that MoGep4 regulates mitophagy, Mps1 phosphorylation and pathogenesis in M. oryzae. In addition, we found that the MoGep4 inhibitor, AXD, displays broad‐spectrum antifungal activity and is a promising candidate for fungicide development. Summary Statement: This study demonstrated that MoGep4 regulates mitophagy, Mps1 activation and pathogenesis in Magnaporthe oryzae. Additionally, we found that the MoGep4 inhibitor, alexidine dihydrochloride, displays broad‐spectrum antifungal activity and is effective in disease control in the field. [ABSTRACT FROM AUTHOR]

Item response time data were used in investigating the differences in student test-taking behavior between two device conditions: computer and tablet. Analyses were conducted to address the questions of whether or not the device condition had a differential impact on rapid guessing and solution behaviors (with response time effort used as an indicator) as well as on the time that students spent on the test (reading, mathematics, and science) or a given item type (such as drag-and-drop and fill in blank). Further analyses were conducted to examine if the potential impact of device conditions varied by gender and ethnicity groups. Overall there were no significant differences in response time effort related to device, although some differences related to item type and test sequence were noted. Students tended to spend slightly more time when taking the tests and certain types of items on the tablet than on the computer. No interactions of device with gender or ethnicity were observed. Follow-up research on the item time thresholds is discussed.

The use of tablets for large-scale testing programs has transitioned from concept to reality for many state testing programs. This study extended previous research on score comparability between tablets and computers with high school students to compare score distributions across devices for reading, math, and science and to evaluate device effects for gender and ethnicity subgroups. Results indicated no significant differences between tablets and computers for math and science. For reading, a small device effect favoring tablets was found for the middle to lower part of the score distribution. This effect seemed to be driven by increases in performance for male students when testing on tablets. No interactions of device with ethnicity were observed. Consistent with previous research, this study provides additional evidence for a relatively high degree of comparability between tablets and computers.

The definition of what it means to take a test online continues to evolve with the inclusion of a broader range of item types and a wide array of devices used by students to access test content. To assure the validity and reliability of test scores for all students, device comparability research should be conducted to evaluate the impact of testing device on student test performance. The current study looked at the comparability of test scores across tablets and computers for high school students in three commonly assessed content areas and for a variety of different item types. Results indicate no statistically significant differences across device type for any content area or item type. Student survey results suggest that students may have a preference for taking tests on devices with which they have more experience, but that even limited exposure to tablets in this study increased positive responses for testing on tablets.

There is increasing expectation that schools should be able to use tablets for a range of instructional and assessment purposes. This article considers the comparability of student writing on tablets and laptops to ensure that writing assessment is conducted in a way that is fair to all students. Data were collected from a sample of 826 students from Virginia and South Dakota at 2 grade levels. Each student was provided with a laptop, a tablet, or a tablet with an external keyboard and asked to respond to a grade-level-appropriate essay prompt. Results indicated no difference in the essay score or surface-level essay features across study conditions. However, the relatively short length of essays written, the fact that reference materials were not required to respond to the essay prompts, and the general motivational level of student participants were likely contributing factors to the observed outcomes.

Previous research has shown that rapid-guessing behavior can degrade the validity of test scores from low-stakes proficiency tests. This study examined, using hierarchical generalized linear modeling, examinee and item characteristics for predicting rapid-guessing behavior. Several item characteristics were found significant; items with more text or those occurring later in the test were related to increased rapid guessing, while the inclusion of a graphic in a item was related to decreased rapid guessing. The sole significant examinee predictor was SAT total score. Implications of these results for measurement professionals developing low-stakes tests are discussed. (Contains 4 tables, 3 figures and 2 footnotes.)

This study compared four methods for setting item response time thresholds to differentiate rapid-guessing behavior from solution behavior. Thresholds were either (a) common for all test items, (b) based on item surface features such as the amount of reading required, (c) based on visually inspecting response time frequency distributions, or (d) statistically estimated using a two-state mixture model. The thresholds were compared using the criteria proposed by Wise and Kong to establish the reliability and validity of response time effort scores, which were generated on the basis of the specified threshold values. The four methods yielded very similar results, indicating that response time effort is not very sensitive to the particular threshold identification method used. Recommendations are given regarding use of the various methods. (Contains 5 tables and 1 figure.)

Excessive fluoride in natural water ecosystem has the potential to detrimentally affect amphibians, but little is known of such effects or underlying mechanisms in Bufo gargarizans embryos. In the present study, the effects of fluoride exposure on B. gargarizans embryos were investigated. First, fluoride teratogenic experiment showed that the 9 days EC50 of fluoride on B. gargarizans embryos was 177.62 mg/L. Then, we studied the sublethal effects of fluoride on B. gargarizans embryos at control, 0.7, 4.1, 19.6, 41.9, and 62.7 mg/L fluoride concentration. Malformation, growth, and development of embryos were monitored, and type 2 and 3 iodothyronine deiodinase (Dio2 and Dio3), thyroid hormone receptors (TRα and TRβ) mRNA levels were measured. Our results showed the morphological malformations, such as tail curvature (lordosis), edema, cuticularized ciliated cells, and hyperplasia were occurred during fluoride exposure. Growth and development were all inhibited at 19.5, 41.9, and 62.7 mg/L fluoride‐treated groups after 9 days’ exposure. According to real‐time PCR results, exposure to fluoride upregulated Dio3 and TRβ mRNA expression and downregulated Dio2 and TRα mRNA level. All above indicated that excessive fluoride could induce morphology malformations, inhibit embryonic growth and development, and disrupt the normal function of maternal thyroid hormone in B. gargarizans embryos. Environ. Mol. Mutagen. 59:123–133, 2018. © 2017 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]