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Premise: The measurement of leaf morphometric parameters from digital images can be time-consuming or restrictive when using digital image analysis softwares. The Multiple Leaf Sample Extraction System (MuLES) is a new tool that enables high-throughput leaf shape analysis with minimal user input or prerequisites, such as coding knowledge or image modification. Methods and Results: MuLES uses contrasting pixel color values to distinguish between leaf objects and their background area, eliminating the need for color threshold-based methods or color correction cards typically required in other software methods. The leaf morphometric parameters measured by this software, especially leaf aspect ratio, were able to distinguish between large populations of different accessions for the same species in a high-throughput manner. Conclusions: MuLES provides a simple method for the rapid measurement of leaf morphometric parameters in large plant populations from digital images and demonstrates the ability of leaf aspect ratio to distinguish between closely related plant types.

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Chemosensation plays a role in the behaviors and life cycles of numerous organisms, including nematodes. Many guilds of nematodes exist, ranging from the free-living Caenorhabditis elegans to various parasitic species such as entomopathogenic nematodes (EPNs), which are parasites of insects. Despite ecological differences, previous research has shown that both EPNs and C. elegans respond to prenol (3-methyl-2-buten-1-ol), an odor associated with EPN infections. However, it is unclear how C. elegans responds to prenol. By utilizing natural variation and genetic neuron ablation to investigate the response of C. elegans to prenol, we found that the AWC neurons are involved in the detection of prenol and that several genes (including dcap-1, dcap-2, and clec-39) influence response to this odorant. Furthermore, we identified that the response to prenol is mediated by the canonically proposed pathway required for other AWC-sensed attractants. However, upon testing genetically diverse isolates, we found that the response of some strains to prenol differed from their response to isoamyl alcohol, suggesting that the pathways mediating response to these two odorants may be genetically distinct. Further, evaluations leveraging natural variation and genome wide association revealed specific genes that influence nematode behavior and provide a foundation for future studies to better understand the role of prenol in nematode behavioral ecology.

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BACKGROUND: Field sepsis alerts have the ability to expedite initial ED sepsis treatment. Our hypothesis is that in patients that meet EMS sepsis alert criteria there is a strong relationship between prehospital end-tidal carbon dioxide (ETCO2) readings and the outcome of diagnosed infection. METHODS: In 2014, our EMS service initiated a protocol requiring hospitals to receive notification of a "sepsis alert" on all suspected sepsis patients. The EMS service transports 70,000 patients/year to a number of urban centers. All patients transported to our major urban teaching hospital by our EMS service in one year in which a sepsis alert was announced were included in this study. The primary outcome variable was diagnosed infection and secondary outcomes were hospital admission, ICU admission and mortality. Positive lactate was defined as >4.0 mmol/L. ROC curve analysis was used to define the best cutoff for ETCO2. RESULTS: 351 patients were announced as EMS sepsis alert patients and transported to our center over a one year period. Positive outcomes were as follows: diagnosed infection in 28% of patients, hospital admission in 63% and ICU admission in 11%. The correlation between lactate and ETCO2 was -0.45. A ROC curve analysis of ETCO2 vs. lactate >4 found that the best cutoff to predict a high lactate was an ETCO2 of 25 or less, which was considered a positive ETCO2 (AUC = 0.73). 27% of patients had a positive ETCO2 and 24% had a positive lactate. A positive ETCO2 predicted a positive lactate with 76% accuracy, 63% sensitivity and 80% specificity. 27% of those with a positive ETCO2 and 44% of those with a positive lactate had a diagnosed infection. 59% of those with a positive ETCO2 and 89% of those with a positive lactate had admission to the hospital. 15% of those with a positive ETCO2 and 18% of those with a positive lactate had admission to the ICU. Neither lactate nor ETCO2 were predictive of an increased risk for diagnosed infection, hospital admission or ICU admission in this patient population. CONCLUSION: While ETCO2 predicted the initial ED lactate levels it did not predict diagnosed infection, admission to the hospital or ICU admission in our patient population but did predict mortality.

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The carmine spider mite (Tetranychus cinnabarinus [Acarifonnes: Tetranychidae]) and the two-spotted spider mite (Tetranychus urticae [Acarifonnes: Tetranychidae]) are two notorious pests of agricultural crops. Control of these pests has been dependent upon using different kinds of acaricides. The purpose of this study was to determine the differential responses of these two pest species collected from crops in the same field to acaricide treatments. Field trials have shown that without spraying acaricides, T. cinnabarinus will displace T. urticae. However, the application of abamectin has the potential to change the composition of spider mite complexes and facilitate the interspecific competition of T. urticae against T. cinnabarinus when both are fed on cowpeas and eggplants. Moreover, T. urticae is more prone to develop resistance than T. cinnabarinus when selected in the laboratory using cyflumetofen or fenpropathrin. After 20 generations of acaricide selection, the activities of detoxifying enzymes were considerably higher in T. urticae with more detoxifying enzymes upregulated after selection in this species. The results of this study demonstrate that differential responses to acaricide treatments have made it possible for T. urticae to overcome the competitive advantage present in T. cinnabarinus during the absence of acaricide application.

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The development of CRISPR/Cas9 technologies has dramatically increased the accessibility and efficiency of genome editing in many organisms. In general, in vivo germline expression of Cas9 results in substantially higher activity than embryonic injection. However, no transgenic lines expressing Cas9 have been developed for the major mosquito disease vector Aedes aegypti Here, we describe the generation of multiple stable, transgenic Ae. aegypti strains expressing Cas9 in the germline, resulting in dramatic improvements in both the consistency and efficiency of genome modifications using CRISPR. Using these strains, we disrupted numerous genes important for normal morphological development, and even generated triple mutants from a single injection. We have also managed to increase the rates of homology-directed repair by more than an order of magnitude. Given the exceptional mutagenic efficiency and specificity of the Cas9 strains we engineered, they can be used for high-throughput reverse genetic screens to help functionally annotate the Ae. aegypti genome. Additionally, these strains represent a step toward the development of novel population control technologies targeting Ae. aegypti that rely on Cas9-based gene drives.

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