SCREENING ANTIBACTERIAL ACTIVITY OF VIETNAMESE PLANT EXTRACTS AGAINST HUMAN PATHOGENIC BACTERIA

Objectives: Infectious diseases caused by bacteria are a leading cause of death worldwide. Hence, the objectives of the study are aimed to evaluate the antibacterial activity against five human pathogenic bacteria of methanolic extracts from 66 plants collected from Vietnam. Methods: The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of methanol extracts of 66 plant species against five bacterial strains. Results: In this study, all the plant extracts were active against at least one train with MIC values ranging from 24 to 2048 μg/mL. Twenty-five plant extracts were active against all three Gram-positive bacteria (Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus). Of these, the extracts of Macaranga trichocarpa (Rchb. f. and Zoll.) Mull. Arg. (Euphorbiaceae), Calophyllum inophyllum L. (Clusiaceae) and Caryodaphnopsis baviensis (Lecomte) Airy Shaw (Lauraceae) exhibited the highest antibacterial activity (MIC =24–128 μg/mL), followed by extracts of Betula alnoides Buch.- Ham. e × . D. Don (Betulaceae), Acronychia pedunculata (L.) Miq. (Rutaceae), Croton alpinus A. Chev. ex Gagnep. (Euphorbiaceae) (MIC =64–256 μg/mL). Furthermore, the extract of Rhus chinensis Mill. (Anacardiaceae) and Annona reticulata L. (Annonaceae) exhibited potent antibacterial activity against the two Bacillus species (MIC =32–64 μg/mL). Conclusion: Results of this study reveal that plant extracts from Vietnam have highly antibacterial activity against Gram-positive bacteria. These results suggest that Vietnamese plant extracts may be a rich source of antibacterial drugs

A Study Of UV-curable Offset Ink Emulsified With An Alternative Isopropyl Alcohol-free Fountain Solution

In the present research, fountain solution without isopropyl alcohol (IPA) for Ultraviolet offset curing ink (UV ink) was prepared by using Ethylene Glycol Mono-butyl Ether (EGME) as a substitute for IPA. The effect of EGME concentration on the water pick-up characteristics, tack value, rheological behaviors, and curing time of UV offset inks was investigated. Water pick-up characteristics, tack value and rheological behaviors were measured by Duke Ink water emulsification tester, Tack-o-scope and cone-plate rheometer, respectively. The curing time of the UV ink was evaluated by the rub test of printed sheet samples proofed on the polymer film at the standard solid ink density and the same ink thickness. The results revealed that an increase in EGME concentration increased the water pick-up characteristics of the UV ink. There was no significant influence of EGME on the tack value of UV inks. However, the tack value of UV ink was significantly affected by fountain concentration in UV inks and UV ink color. The addition of EGME reduced the dynamic viscosity and thixotropic property of UV inks but did not change the flow behavior of UV ink as shear thinning. This study indicates that UV ink emulsified with a higher EGME concentration fountain solution needs a longer curing time. The cyan UV ink has the longest curing time. Finally, the fountain solution of 10% EGME exhibited good performance in water pick-up characteristics, tack value, rheological behaviors, and curing time of UV inks

Network Coding with Multimedia Transmission and Cognitive Networking: An Implementation based on Software-Defined Radio

Network coding (NC) is considered a breakthrough to improve throughput, robustness, and security of wireless networks. Although the theoretical aspects of NC have been extensively investigated, there have been only few experiments with pure NC schematics. This paper presents an implementation of NC under a two-way relay model and extends it to two non-straightforward scenarios: (i) multimedia transmission with layered coding and multiple-description coding, and (ii) cognitive radio with Vandermonde frequency division multiplexing (VFDM). The implementation is in real time and based on software-defined radio (SDR). The experimental results show that, by combining NC and source coding, we can control the quality of the received multimedia content in an on-demand manner. Whereas in the VFDM-based cognitive radio, the quality of the received content in the primary receiver is low (due to imperfect channel estimation) yet retrievable. Our implementation results serve as a proof for the practicability of network coding in relevant applications

New quinazolinone-based Mannich bases: Synthesis and in vitro cytotoxic evaluation

This research presents the synthesis of new quinazolinone-based Mannich bases in good yields via a three-step procedure. The first step is the reaction of 6-hydroxyanthranilic acid 1 with an excess of acetic anhydride at 150°C for 2 h to afford benzoxazinone 2 in 87% yield. Compound 2 is then reacted with 4-aminophenol in DMSO at reflux for 7 h to give compound 3 in 75% yield. Finally, the reaction of 3 with paraformadehyde and secondary amines in ethanol affords new quinazolinone-based Mannich bases 4a-c and 5a-e in 55-70% yields. The structure of Mannich bases have been characterized by NMR and MS spectra. The bio-assay results show that some new Mannich bases exhibited weak to moderate cytotoxic activity against SKLu-1 and MCF-7 cell lines

Network Coding with Multimedia Transmission and Cognitive Networking: An Implementation based on Software-Defined Radio

Network coding (NC) is considered a breakthrough to improve throughput, robustness, and security of wireless networks. Although the theoretical aspects of NC have been extensively investigated, there have been only few experiments with pure NC schematics. This paper presents an implementation of NC under a two-way relay model and extends it to two\ua0non-straightforward scenarios: (i) multimedia transmission with layered coding and multiple-description coding, and (ii) cognitive radio with Vandermonde frequency division multiplexing (VFDM). The implementation is in real time and based on software-defined radio (SDR). The experimental results show that, by combining NC and source coding, we can control the quality of the received multimedia content in an on-demand manner. Whereas in the VFDM-based cognitive radio, the quality of the received content in the primary receiver is low (due to imperfect channel estimation) yet retrievable. Our implementation results serve as a proof for the practicability of network coding in relevant applications

A formal proof of the Kepler conjecture

This article describes a formal proof of the Kepler conjecture on dense sphere packings in a combination of the HOL Light and Isabelle proof assistants. This paper constitutes the official published account of the now completed Flyspeck project

Iridoid glycosides from Morinda tomentosa and their endoplasmic reticulum stress modulation activity

Three iridoids 1 - 3, asperulosidic acid, daphylloside, and asperuloside, were isolated from the methanol extract of the leaves of Morinda tomentosa. Their chemical structures were elucidated by 1D- and 2D-NMR spectra and in comparison with those reported in the literature. The effects of these compounds on the endoplasmic reticulum stress in XBP1-eGFP-transfected the 293 T cells were measured. Compound 3 significantly reduced the ER-stress both in DMSO-treated and thapsigargin-treated cells. Unlike this compound, compound 3 selectively reduced thapsigargin-induced ER-stress without any effect on the level of XBP1 splicing in DMSO-treated cells. These results suggested that compounds 2 and 3 can be suggested as new ER stress regulators

Characterizing pig value chains in Vietnam: descriptive analysis from survey data

The traditional pig sector plays a significant role in Vietnam’s economy from production, especially for farmers in rural areas, to consumption (more than 90% of pork consumed is supplied by conventional wet markets). At the same time, the traditional pig sector is under threat from animal health and food safety risks that impact both its profitability and future viability. However, little research exists on defining key intervention points that could manage risks in a propoor, cost-effective manner. Our study highlighted and reviewed the contrast between pig value chains in two provinces (Hung Yen and Nghe An) that represent different levels of economic development in the county. Based on semi-structured questionnaires, 400 pig producing farmers and 400 pork consumers were surveyed in both provinces during July and August 2013, paying particular attention to typologies of production and consumption in rural, semi-urban, and urban zones. We also obtained information on 200 other intermediary value chain actors through semi-structured and in-depth interviews. Preliminary descriptive analysis revealed the main characteristics of various actors in the sampled value chains, including (vet and feed) input suppliers, producers, traders, slaughterhouses (or abattoirs), processors, retailers, and consumers. In particular, we found that actors in Hung Yen are more likely to be active and commercialised in pig value chains than those in Nghe An. At the same time, Nghe An is exposed to operate its chains more ‘self-sufficiently’, with ownproduced inputs, particularly feeds, and has more state-owned farms involved in breed supply. In both study sites, middlemen often perform multiple functions and are generally the most powerful actors in the surveyed chains since they have better access to information and dominate value-added activities. This may imply a potential control point for risk management in response to diseases transmitted in short-term as well as (pro-poor) profit distribution in longerterm. Moreover, the behaviours of actors in these two provinces are dissimilar in terms of production and consumption practices as a result of differences in production scale, knowledge, attitude and habits. Information from this study will provide more insightful understanding of these existing value chains and serve as the base for further economic and risk analysis