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Plant pathogenic fungi and bacteria cause large losses in the yield and quality of important crops. During the screening of bioactive plants against plant pathogens, we found that methanol extract of the aerial part of Rumex chinensis exhibited potent efficacy against various plant diseases. The methanol extract was effectively active against phytopathogenic fungi Blumeria graminis f. sp. hordei and Colletotrichum coccodes that cause plant diseases in vivo. n-Hexane and ethyl acetate layers obtained by liquid-liquid partitioning of the methanol extract strongly suppressed these fungal diseases with control values from 83 to 100% at 3000 µg/mL. These layers also inhibited the bacterial growth of Acidovorax avenae subsp. cattleyae and Ralstonia solanacearum. Notably, the n-hexane layer was found to reduce the development of tomato bacterial wilt in vivo. Six anthraquinones and two sterols were isolated from the aerial part of R. chinensis. Besides, the high-performance liquid chromatography (HPLC) was used for the quantitative analysis of anthraquinone contents in the active layers. The aerial part of R. chinensis was proved to be rich in active substances physcion, chrysophanol and emodin and their glycoside derivatives. Our findings suggested that the extracts and metabolites from the aerial part of R. chinensis could be used as potent active ingredients for developing botanical fungicide and bactericide to control plant diseases.

Objective. To characterize the types of cognitive and metacognitive processes demonstrated by third-year pharmacy students during a therapeutic reasoning activity. Methods. A qualitative, descriptive study following a think-aloud protocol was used to analyze the cognitive (analytical) and metacognitive processes observed by third-year pharmacy students as they completed a 25-minute therapeutic reasoning activity. Using a deductive codebook developed from literature about reasoning, two independent coders characterized processes from students’ audio-recorded, transcribed think-aloud episodes while making therapeutic decisions about simulated clinical cases. Results. A total of 40 think-aloud episodes were transcribed among the cohort. Categorization of the think-aloud transcriptions revealed a series of cognitive analytical and metacognitive processes demonstrated by students during the therapeutic decision-making activity. A total of 1792 codes were categorized as analytical processes, falling into six major themes: 69% gathering information (1232/1792), 13% processing information (227/1792), 7% making assessments (133/1792), 1% synthesizing information (19/1792), 7% articulating evidence (117/1792), and 4% making a recommendation (64/1792). In comparison to gathering information, a much lower frequency of processing and assessment was observed for students, particularly for those that were unable to resolve the case. Students’ movement between major analytical processes co-occurred commonly with metacognitive processes. Of the 918 codes categorized as metacognitive processes, two major themes arose: 28% monitoring for knowledge or emotions (257/918) and 72% controlling the planning of next steps or verification of correct information (661/918). Sequencing the codes and co-occurrences of processes allowed us to propose an integrated cognitive/metacognitive model of therapeutic reasoning for students. Conclusion. This study categorizes the cognitive (analytical) and metacognitive processes engaged during pharmacy students’ therapeutic reasoning process. The findings can inform current instructional practices and further research into educational activities that can strengthen pharmacy students’ therapeutic reasoning skills.

Internet of Things (IoT) has enabled physical devices and virtual objects to be connected to share data, coordinate, and automatically make smart decisions to server people. Recently, many IoT resource slicing studies that allow managing devices, IoT platforms, network functions, and clouds under a single unified programming interface have been proposed. Although they helped IoT developers to create IoT services more easily, the efforts still have not dealt with the monitoring problem for the slice components. This could cause an issue: thing states could not be tracked continuously, and hence the effectiveness of controlling the IoT components would be decreased significantly because of updated information lack. In this paper, we introduce an information-centric approach for multiple sources monitoring issue in IoT. The proposed model thus is designed to provide generic and extensible data format for diverse IoT objects. Through this model, IoT developers can build smart services smoothly without worrying about the diversity as well as heterogeneity of collected data. We also propose an overall monitoring architecture for the information-centric model to deploy in IoT environment and its monitoring API prototype. This document also presents our experiments and evaluations to prove feasibility of the proposals in practice.

The antimicrobial efficacies of extracts and constituents fractionated from Rheum tanguticum rhizomes were evaluated by using in vitro and in vivo bioassay against seven phytopathogenic fungi and ten pathogenic bacteria, respectively. Dichloromethane and ethyl acetate soluble extracts derived from R. tanguticum rhizomes effectively controlled plant diseases caused by five fungi Magnaporthe oryzae, Blumeria graminis f. sp. hordei, Colletotrichum coccodes, Phytophthora infestans, and Puccinia recondita in in vivo whole plant bioassay. In addition, these extracts showed strong inhibitory activity against the bacterial growth of Acidovorax avenae subsp. cattlyae (Aac), Clavibacter michiganensis subsp. michiganensis, Xanthomonas arboricola pv. pruni (Xap), and Pseudomonas syringae pv. actinidiae (Psa), with MIC values ranging from 125 to 250 μg/mL. The active extracts of R. tanguticum rhizomes were fractionated by using various and repeated chromatographic techniques to yield seven constituents that included three anthraquinones and four stilbenes. Notably, at concentrations ranging from 75 to 300 μg/mL, physcion (DH03) and chrysophanol (DH04) were significantly effective in suppressing the development of barley powdery mildew (BPM) caused by B. graminis f. sp. hordei, with control values from 80 to 96.7%. Moreover, stilbenes rhapontigenin (DH02) and desoxyrhapontigenin (DH05) had a broad spectrum and potent activity against phytopathogenic bacteria; DH05 effectively inhibited the bacterial growth of Aac, Burkholderia glumae and Psa at MICs ranging from 38 to 150 μg/mL. In this paper, we report their antibacterial activity for the first time. The botanical materials containing anthraquinones and stilbenes were active against both phytopathogenic fungi and bacteria. These results suggested that R. tanguticum rhizomes could be used as a new source of antimicrobial substances for developing a botanical fungicide and bactericide to control plant diseases.

In this work, a photonic-silicon-based 1✕3 reconfigurable simultaneous three-mode selective router has been demonstrated by the proof-of-concept. The device can be flexibly controlled to route three input modes of TE0, TE1, and TE2 to three outputs by utilizing three controllable Ti thermo-optic phase shifters as drivers. The proposed router is constructed from a Ψ -junction coupler and two kinds of 3✕3 multi-mode interference (MMI) couplers. The proposed device can attain low insertion loss smaller than 5 dB and crosstalk below −20 dB in broadband of 40-nm thanks to the numerical simulation-based optimization. Furthermore, the proposed router has relatively large fabrication tolerances of width and height and consumes a low electric power consumption. The proposed device is reconfigurable for simultaneous three guided modes, and thus, leading to a promising potential to widely apply for broadband optical signal processing in the mode-division multiplexing systems.

The use of synthetic chemicals in agriculture has not only caused humans and animals’ health risks but also environmental pollution. Botanical pesticides have been considered as alternatives to harmful pesticides because of their low toxicity and easy biodegradable property. The objective of this study was to evaluate the antimicrobial activities of the extracts and metabolites from the leaves of Cassia alata L. against fungal and bacterial phytopathogens. Ethyl acetate-soluble extract derived from C. alata leaves has been found to remarkably control the plant diseases caused by fungi Magnaporthe oryzae, Phytophthora infestans, Colletotrichum coccodes and Puccinia recondita in vivo. To provide scientific evidence on the effectiveness of the ethyl acetate-soluble extract against plant pathogens, the bioassay-guided fractionation of the extract was conducted and thereby eight compounds including methyl 2,4,6-trihydroxybenzoate (1), aloe-emodin (2), kaempferol (3), (-)-epiafzelechin (4), rhein (5), kaempferol-3-O-glycoside (6), kaempferol-3-O-gentiobiside (7) and aloe-emodin-8-O-β-D-glucoside (8) were identified. The content of 2, 5, and 8 in the ethyl acetate-soluble extract and methanol extract of C. alata leaves were quantified by HPLC analysis. Compounds 3-8 displayed in vitro antifungal activity against M. oryzae and Phytophthora species. Out of the isolated compounds, rhein (5) displayed the best antifungal activity; it strongly inhibited in vitro the mycelial growth of Phytophthora species and effectively suppressed tomato late blight (TLB) by 57.1 % at 150 μg/mL and 87.9 % at 300 μg/mL on the tomato seedlings in vivo. Besides, rhein showed excellent in vitro inhibition for the bacterial growth of Acidovorax avenae subsp. cattlvae with an IC50 of 2.5 μg/mL. From the results, it was confirmed that the ethyl acetate-soluble extract derived from C. alata leaves contains antimicrobial constituents against various plant pathogens and has potent in vivo efficacy for controlling plant diseases.