47 research outputs found

    Inhibition of Helicoverpa armigera gut pro-proteinase activation in response to synthetic protease inhibitors

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    Protease inhibitors play an important role in host plant defence against herbivores. However, insects have the ability to elevate the production of proteinases or resort to production of a diverse array of proteinases to offset the effect of proteinase inhibitors. Therefore, we studied the inhibition of pro-proteinase(s) activation in the midgut of the polyphagous pest Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in response to protease inhibitors to develop appropriate strategies for the control of this pest. Gelatin coating present on X-ray film was used as a substrate to detect electrophoretically separated pro-proteinases and proteinases of H. armigera gut extract on native- and sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Six activated pro-proteinase bands were detected in H. armigera gut lumen, which were partially purified and characterized using substrate assays. Activated H. armigera midgut pro-proteinase(s) showed activity maxima at pH 8 and 10, and exhibited optimal activity at 40 °C. The activation of H. armigera gut pro-proteinase isoforms was observed in the fraction eluted on benzamidine-sepharose 4B column. Purification and substrate assay studies revealed that 23–70 kDa polypeptides were likely the trypsin/chymotrypsin-like pro-proteinases. Larvae of H. armigera fed on a cocktail of synthetic inhibitors (antipain, aprotinin, leupeptin, and pefabloc) showed maximum activation of pro-proteinases compared with the larvae fed on individual inhibitors. The implications of these results for developing plants expressing proteinase inhibitors for conferring resistance to H. armigera are discussed

    In vivo inhibition of Helicoverpa armigera gut pro-proteinase activation by non-host plant protease inhibitors

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    We evaluated 22 different host and non-host plant protease inhibitors (PIs) for in vivo inhibition of Helicoverpa armigera gut pro- and proteinases, and their biological activity against the pod borer, H. armigera, the most important pest of agriculture and horticultural crops worldwide. In vitro activation of H. armigera gut pro-proteinases (HaGPPs) in larvae fed on non-host plant PIs showed significant in vivo inhibition of HaGPPs activation in solution as well as in gel assays. The larvae fed on diet incorporated with Datura alba ness PIs showed highest inhibition of HaGPPs, followed by Psophocarpus tetragonolobus. Non-host plant PIs from Pongamia pinnata, Mucuna pruriens, Capsicum annuum, and Nigela sativa showed maximum inhibitory potential towards HaGPs in vivo, and also exhibited moderate level of inhibition of pro-proteinases. However, some of non-host plant PIs, such as those from Penganum harmala and Solanum nigrum, and the principal host plant PIs, viz., Cicer arietinum and Cajanus cajan did not inhibit HaGPP activity. Pro-proteinase level increased with the growth of the larvae, and maximum HaGPP activity was observed in the fifth-instars. Larvae fed on diets with D. alba ness PIs showed greater inhibition of HaGPPs as compared to the larvae fed on diets with P. tetragonolobus. Low concentrations of partially purified HaGPs treated with gut extract of larvae fed on D. alba ness showed that out of 10 proteinase isoforms, HaGPs 5 and 9 were activators of pro-proteinases. Larval growth and development were significantly reduced in the larvae fed on the non-host plant PIs, of which D. alba ness resulted in highest stunted growth of H. armigera larvae. The in vivo studies indicated that non-host plant PIs were good candidates as inhibitors of the HaGPs as well as HaGPPs. The PIs from the non-host plants can be expressed in genetically engineered plants to confer resistance to H. armigera

    Protease Inhibitors in Wild Relatives of Pigeonpea against the Cotton Bollworm/Legume Pod Borer, Helicoverpa armigera

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    Cotton bollworm/legume pod borer, Helicoverpa armigera is one of the most damaging pests worldwide. Because of the difficulties associated with chemical control of this pest, emphasis has been placed on developing transgenic plants with resistance to this pest. Since toxin genes from the bacterium, Bacillus thuringiensis (Bt) have been deployed on a large scale, there is need to scout for alternate genes which could be deployed alone or in combination with the Bt genes for pest management. Therefore, we evaluated the wild relatives of pigeonpea, which have shown high levels of resis-tance to this pest, for the protease inhibitors (PIs) under in vivo and in vitro inhibitions. Accession belonging to Cajanus albicans, C. cajanifolius, C. sericeus, Flemingia bracteata, and Rhynchosia bracteata showed complete inhibition of H. armigera gut proteinases (HaGPs). Some of the C. scarabaeoides accessions (ICPW 116, 152, 278 and 280) exhibited partial inhibition at low concentrations of the PIs. All accessions of wild relatives of pigeonpea showed high to moder-ate level of inhibition at pH 7.8. Cultivated pigeonpea, ICPL 87 exhibited monomorphism in terms of trypsin inhibitor (TI) and chymotrypsin inhibitor (CTI) isoforms, contrary to the diverse inhibitory profiles of wild pigeonpeas. Cajanus albicans, C. platycarpus, C. scarabaeoides, and R. bracteata showed more number of TI and CTI bands than the culti-vated pigeonpea. Protease inhibitor isoforms of wild relatives of pigeonpea showed significant variation in number, band pattern, and protein specificities towards trypsin, chymotrypsin, and H. armigera gut proteinases (HaGPs) as compared to the cultivated pigeonpea. The PIs from the wild relatives of pigeonpea showed considerable potential against the HaGPs, and could be considered as potential candidates for use in genetic transformation of crops for pest management, including H. armigera

    Lessons Learned: Development of COVID-19 Clinical Staging Models at a Large Urban Research Institution

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    BACKGROUND/OBJECTIVE: The University of Illinois at Chicago (UIC), along with many academic institutions worldwide, made significant efforts to address the many challenges presented during the COVID-19 pandemic by developing clinical staging and predictive models. Data from patients with a clinical encounter at UIC from July 1, 2019 to March 30, 2022 were abstracted from the electronic health record and stored in the UIC Center for Clinical and Translational Science Clinical Research Data Warehouse, prior to data analysis. While we saw some success, there were many failures along the way. For this paper, we wanted to discuss some of these obstacles and many of the lessons learned from the journey. METHODS: Principle investigators, research staff, and other project team members were invited to complete an anonymous Qualtrics survey to reflect on the project. The survey included open-ended questions centering on participants' opinions about the project, including whether project goals were met, project successes, project failures, and areas that could have been improved. We then identified themes among the results. RESULTS: Nine project team members (out of 30 members contacted) completed the survey. The responders were anonymous. The survey responses were grouped into four key themes: Collaboration, Infrastructure, Data Acquisition/Validation, and Model Building. CONCLUSION: Through our COVID-19 research efforts, the team learned about our strengths and deficiencies. We continue to work to improve our research and data translation capabilities

    BWIBots: A platform for bridging the gap between AI and human–robot interaction research

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    Recent progress in both AI and robotics have enabled the development of general purpose robot platforms that are capable of executing a wide variety of complex, temporally extended service tasks in open environments. This article introduces a novel, custom-designed multi-robot platform for research on AI, robotics, and especially human–robot interaction for service robots. Called BWIBots, the robots were designed as a part of the Building-Wide Intelligence (BWI) project at the University of Texas at Austin. The article begins with a description of, and justification for, the hardware and software design decisions underlying the BWIBots, with the aim of informing the design of such platforms in the future. It then proceeds to present an overview of various research contributions that have enabled the BWIBots to better (a) execute action sequences to complete user requests, (b) efficiently ask questions to resolve user requests, (c) understand human commands given in natural language, and (d) understand human intention from afar. The article concludes with a look forward towards future research opportunities and applications enabled by the BWIBot platform

    Missing Information, Unresponsive Authors, Experimental Flaws: The Impossibility of Assessing the Reproducibility of Previous Human Evaluations in NLP

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    We report our efforts in identifying a set of previous human evaluations in NLP that would be suitable for a coordinated study examining what makes human evaluations in NLP more/less reproducible. We present our results and findings, which include that just 13% of papers had (i) sufficiently low barriers to reproduction, and (ii) enough obtainable information, to be considered for reproduction, and that all but one of the experiments we selected for reproduction was discovered to have flaws that made the meaningfulness of conducting a reproduction questionable. As a result, we had to change our coordinated study design from a reproduce approach to a standardise-then-reproduce-twice approach. Our overall (negative) finding that the great majority of human evaluations in NLP is not repeatable and/or not reproducible and/or too flawed to justify reproduction, paints a dire picture, but presents an opportunity for a rethink about how to design and report human evaluations in NLP

    Biochemical components of wild relatives of chickpea confer resistance to pod borer, Helicoverpa armigera

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    Efforts are being made to develop chickpea varieties with resistance to the pod borer, Helicoverpa armigera for reducing pesticide use and minimizing the extent of losses due to this pest. However, only low to moderate levels of resistance have been observed in the cultivated chickpea to this polyphagous pest. Hence, it is important to explore wild relatives as resistance sources to develop insect-resistant cultivars. Therefore, we studied different biochemical components that confer resistance to H. armigera in a diverse array of wild relatives of chickpea. Accessions belonging to wild relatives of chickpea exhibited high levels of resistance to H. armigera as compared to cultivated chickpea genotypes in terms of lower larval survival, pupation and adult emergence, decreased larval and pupal weights, prolonged larval and pupal developmental periods and reduced fecundity of the H. armigera when reared on artificial diet impregnated with lyophilized leaf powders. Amounts of proteins and phenols in different accessions of chickpea wild relatives were significantly and negatively correlated with larval weight, pupation and adult emergence. Phenols showed a negative correlation with pupal weight and fecundity, but positive correlation with pupal period. Total soluble sugars showed a negative correlation with larval period, but positive correlation with pupation and pupal weight, while tannins showed a positive correlation with larval weight, pupation and adult emergence. The flavonoid compounds such as chlorogenic acid, ferulic acid, naringin, 3,4-dihydroxy flavones, quercetin, naringenin, genistein, biochanin-A and formononetin that were identified through HPLC fingerprints, exhibited negative effects on survival and development of H. armigera reared on artificial diet impregnated with lyophilized leaf powders. The wild relatives with diverse mechanisms of resistance conferred by different biochemical components can be used as sources of resistance in chickpea breeding programs to develop cultivars with durable resistance to H. armigera for sustainable crop production

    Photosynthetic performance of invasive \u3ci\u3ePinus ponderosa\u3c/i\u3e and \u3ci\u3eJuniperus virginiana\u3c/i\u3e seedlings under gradual soil water depletion

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    Changes in climate, land management and fire regime have contributed to woody species expansion into grasslands and savannas worldwide. In the USA, Pinus ponderosa P. & C. Lawson and Juniperus virginiana L. are expanding into semiarid grasslands of Nebraska and other regions of the Great Plains. We examined P. ponderosa and J. virginiana seedling response to soil water content, one of the most important limiting factors in semiarid grasslands, to provide insight into their success in the region. Photosynthesis, stomatal conductance, maximum photochemical efficiency of PSII, maximum carboxylation velocity, maximum rate of electron transport, stomatal limitation to photosynthesis, water potential, root-to-shoot ratio, and needle nitrogen content were followed under gradual soil water depletion for 40 days. J. virginiana maintained lower Ls, higher A, gs, and initial Fv/Fm, and displayed a more gradual decline in Vcmax and Jmax with increasing water deficit compared to P. ponderosa. J. virginiana also invested more in roots relative to shoots compared to P. ponderosa. Fv/Fm showed high PSII resistance to dehydration in both species. Photoinhibition was observed at ~30% of field capacity. Soil water content was a better predictor of A and gs than Ψ, indicating that there are other growth factors controlling physiological processes under increased water stress. The two species followed different strategies to succeed in semiarid grasslands. P. ponderosa seedlings behaved like a drought-avoidant species with strong stomatal control, while J. virginiana was more of a drought-tolerant species, maintaining physiological activity at lower soil water content. Differences between the studied species and the ecological implications are discussed
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