Adaptive meshing for finite element analysis of heterogeneous materials

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Alphonsea glandulosa (Annonaceae), a new species from Yunnan, China

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Evaluation of the detection techniques of toxigenic Aspergillus isolates

Aflatoxins are difuranocoumarin derivatives produced by some Aspergillus species through a polyketide pathway. Mycotoxins are considered hazardous and there is a need for accurate detection of each toxin. Several screening methods for direct visual determination of aflatoxins and ochratoxin A (OTA) production have been reported. These methods rely on using different types of coconut culture media, methylated â-cyclodextrin and ammonium hydroxide vapour tests. However, our results showed that use of these  techniques were not sufficiently sensitive for all Aspergillus species and suggested a simple thin layer  chromatography (TLC) as a sensitive and reliable technique for detection of aflatoxins and OTA produced by Aspergillus and Eurotium species.Key words: Aspergillus, Eurotium, Mycotoxins detection, thin layer chromatography

Optimal vitamin D status and its relationship with bone and mineral metabolism in Hong Kong Chinese

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Identification of Cellular Targets of MicroRNA-181a in HepG2 Cells: A New Approach for Functional Analysis of MicroRNAs

<div><p>MicroRNAs (miRNAs) are known to play a part in regulating important cellular processes. They generally perform their regulatory function through their binding with mRNAs, ultimately leading to a repression of target protein expression levels. However, their roles in cellular processes are poorly understood due to the limited understanding of their specific cellular targets. Aberrant levels of miRNAs have been found in hepatocellular carcinoma (HCC) including miR-181a. Using bioinformatics analysis, cyclin-dependent kinase inhibitor 1B (CDKN1β) and transcriptional factor E2F7 were identified as potential targets of miR-181a. Validation analysis using surface plasmon resonance (SPR) showed a positive binding between miR-181a and the 3’UTRs of these two potential mRNA targets. <i>In vivo</i> luciferase assay further confirmed the positive miR-181a:mRNA bindings, where a significant decrease in luciferase activity was detected when HepG2 cells were co-transfected with the 3’UTR-containing reporter plasmids and miR-181a. The potential impact of miR-181a binding to its specific targets on the general cellular behavior was further investigated. Results showed that miR-181a significantly activated the MAPK/JNK pathway which regulates cell proliferation, supporting our recently reported findings. Inhibition of miR-181a, on the other hand, abolished the observed activation. Our findings open up a new approach in designing targeted functional analysis of miRNAs in cellular processes, through the identification of their cellular targets.</p></div

Forward with Dementia: process evaluation of an Australian campaign to improve post-diagnostic support

Background: Forward with Dementia is a co-designed campaign to improve communication of dementia diagnosis and post-diagnostic support. Methods: Webinars, a website, social and traditional media, and promotions through project partners were used to disseminate campaign messages to health and social care professionals (primary audience) and people with dementia and carers (secondary audience). The campaign ran between October 2021 and June 2022, with 3-months follow-up. The RE-AIM framework was used for process evaluation. Measurements included surveys and interviews, a log of activities (e.g. webinars, social media posts) and engagements (e.g. attendees, reactions to posts), and Google Analytics. Results: There were 29,053 interactions with campaign activities. More than three-quarters of professionals (n = 63/81) thought webinars were very or extremely helpful. Professionals and people with dementia and carers reported that the website provided appropriate content, an approachable tone, and was easy to use. Following campaign engagement, professionals planned to (n = 77/80) or had modified (n = 29/44) how they communicated the diagnosis and/or provided post-diagnostic information and referrals. Qualitative data suggested that the campaign may have led to benefits for some people with dementia and carers. Conclusions: Forward with Dementia was successful in terms of reach, appropriateness, adoption and maintenance for professionals, however flow-through impacts on people with dementia are not clear. Targeted campaigns can potentially change health professionals’ communication and support around chronic diseases such as dementia

Synthesis and characterisation of coating polyurethane cationomers containing fluorine built-in hard urethane segments

Polyurethane cationomers were synthesised in the reaction of 4,4’-methylenebis(phenyl isocyanate) with polyoxyethylene glycol (M = 2,000) or poly(tetrafluoroethyleneoxide-co-difluoromethylene oxide) α,ω-diisocyanate and N-methyl diethanolamine. Amine segments were built-in to the urethane-isocyanate prepolymer in the reaction with 1-bromobutane or formic acid, and then they were converted to alkylammonium cations. The obtained isocyanate prepolymers were then extended in the aqueous medium that yielded stable aqueous dispersions which were applied on the surfaces of test poly(tetrafluoroethylene) plates. After evaporation of water, the dispersions formed thin polymer coatings. 1H, 13C NMR and IR spectral methods were employed to confirm chemical structures of synthesised cationomers. Based on 1H NMR and IR spectra, the factors κ and α were calculated, which represented the polarity level of the obtained cationomers. The DSC, wide angle X-ray scattering and atom force microscopy methods were employed for the microstructural assessment of the obtained materials. Changes were discussed in the surface free energy and its components, as calculated independently according to the method suggested by van Oss–Good, in relation to chemical and physical structures of cationomers as well as morphology of coating surfaces obtained from those cationomers. Fluorine incorporated into cationomers (about 30%) contributed to lower surface free energy values, down to about 15 mJ/m2. That was caused by gradual weakening of long-range interactions within which the highest share is taken by dispersion interactions

Insights into biofilm dispersal regulation from the crystal structure of the PAS-GGDEF-EAL region of RbdA from Pseudomonas aeruginosa

© 2018 American Society for Microbiology. RbdA is a positive regulator of biofilm dispersal of Pseudomonas aeruginosa. Its cytoplasmic region (cRbdA) comprises an N-terminal Per-ARNT-Sim (PAS) domain followed by a diguanylate cyclase (GGDEF) domain and an EAL domain, whose phosphodiesterase activity is allosterically stimulated by GTP binding to the GGDEF domain. We report crystal structures of cRbdA and of two binary complexes: one with GTP/Mg 2+ bound to the GGDEF active site and one with the EAL domain bound to the c-di-GMP substrate. These structures unveil a 2-fold symmetric dimer stabilized by a closely packed N-terminal PAS domain and a noncanonical EAL dimer. The autoinhibitory switch is formed by an α-helix (S-helix) immediately N-terminal to the GGDEF domain that interacts with the EAL dimerization helix (α6-E) of the other EAL monomer and maintains the protein in a locked conformation. We propose that local conformational changes in cRbdA upon GTP binding lead to a structure with the PAS domain and S-helix shifted away from the GGDEF-EAL domains, as suggested by small-angle X-ray scattering (SAXS) experiments. Domain reorientation should be facilitated by the presence of an α-helical lever (H-helix) that tethers the GGDEF and EAL regions, allowing the EAL domain to rearrange into an active dimeric conformation

A foodborne outbreak of gastroenteritis caused by vibrio parahaemolyticus and norovirus through non-seafood vehicle

Foodborne outbreaks caused by a mixed infection of Vibrio parahaemolyticus and norovirus have rarely been described. We reported a mixed outbreak of Vibrio parahaemolyticus and norovirus causing acute gastroenteritis in 99 staff members of a company in Guangdong, China, in May 2013, following consumption of roasted duck, an uncommon non-seafood vehicle for such mixed infection, in one meal served in the company's catering service. Epidemiological and laboratory findings indicated that a single asymptomatic food handler was the source of both pathogens, and the high rate of infection of both pathogens was exacerbated by the setting's suboptimal food hygiene practice. © 2015 Liu et al.published_or_final_versio