MyMedR

Displaying publications 1 - 20 of 85 in total

Abstract:

Sort:

Fulltext Promising transition metal decorated borophene catalyst for water splitting

Wang R, Zheng JC

RSC Adv, 2023 Mar 20;13(14):9678-9685.
PMID: 36968026 DOI: 10.1039/d3ra00299c

Borophene has been recently reported to be a promising catalyst for water splitting. However, as a newly synthesized two-dimensional material, there are several issues that remain to be explored. In the present study, we investigate the catalytic performance of three kinds of pristine and decorated borophenes using first-principles calculations. Our calculations show that Ni-doped α borophene can be a highly active catalyst for water splitting. Doping or decorating with different transition metals such as Co or Ni at different sites shows a strong effect on the catalytic performance of α, β12 and χ3 borophenes. Ni-doped α borophene shows low Gibbs free energy of hydrogen adsorption (ΔG H ∼ 0.055 eV) for the hydrogen evolution reaction (HER) and promising overpotential (0.455 V) for the oxygen evolution reaction (OER). This study provides some critical insights into the catalytic activity of borophene for water splitting by selecting suitable decorated metal.
ZnO monolayer-supported single atom catalysts for efficient electrocatalytic hydrogen evolution reaction

Wang R, Zheng JC

Phys Chem Chem Phys, 2024 Feb 14;26(7):5848-5857.
PMID: 38299693 DOI: 10.1039/d3cp05241a

Hydrogen is identified as one of the most promising sustainable and clean energy sources. The development of a hydrogen evolution reaction (HER) catalyst with high activity is essential to meet future needs. Considering the novel advantages of two-dimensional materials and the high catalytic activity of atomic transition metals, in this study, using density functional theory calculations, the HER on a single transition metal (10 different TM atoms) adsorbed and doped ZnO monolayer (ZnO-m) has been investigated. The Volmer-Tafel reaction mechanisms and strain engineering of the three best HER catalysts are also discussed. The results show that Pt@ZnO-m, Co-doped ZnO-m and Ir-doped ZnO-m with high stability all have a smaller absolute H adsorption free energy than Pt, and the optimal value of Pt@ZnO-m is -0.017 eV. The calculation of the reaction energy barriers shows that the Volmer-Tafel step is favorable. Co@ZnO-m and Ir@ZnO-m have high HER activity, the widest pH range, and acid-alkali resistance. Pt@ZnO-m and Co-doped ZnO-m maintain excellent HER performances in the strain range of -4% to 4%.
Evaluation of the efficacy of constitutional array-based comparative genomic hybridization in the diagnosis of aneuploidy using genomic and amplified DNA

Tan NH, Palmer R, Wang R

J Obstet Gynaecol Res, 2010 Feb;36(1):19-26.
PMID: 20178523 DOI: 10.1111/j.1447-0756.2009.01110.x

Array-based comparative genomic hybridization (array CGH) is a new molecular technique that has the potential to revolutionize cytogenetics. However, use of high resolution array CGH in the clinical setting is plagued by the problem of widespread copy number variations (CNV) in the human genome. Constitutional microarray, containing only clones that interrogate regions of known constitutional syndromes, may circumvent the dilemma of detecting CNV of unknown clinical significance.
Computational Chemistry in Asia

Wei GW, Soares TA, Wahab H, Wang R

J Chem Inf Model, 2021 02 22;61(2):547.
PMID: 33529020 DOI: 10.1021/acs.jcim.1c00081
Furanoditerpenes of Fibraurea chloroleuca

Zakaria MB, Saito I, Yao XK, Wang RJ, Matsuura T

Planta Med, 1989 Oct;55(5):477-8.
PMID: 17262463

Fibraurin, chasmanthin, and palmarin were isolated from the stems of FIBRAUREA CHLOROLEUCA, Fam. Menispermaceae. The structure of the minor constituent, palmarin, was determined by X-ray crystallographic analysis.
Transcriptome analysis in the skin of Carassius auratus challenged with Aeromonas hydrophila

Wang R, Hu X, Lü A, Liu R, Sun J, Sung YY, et al.

Fish Shellfish Immunol, 2019 Nov;94:510-516.
PMID: 31541778 DOI: 10.1016/j.fsi.2019.09.039

Skin plays an important role in the innate immune responses of fish, particularly towards bacterial infection. To understand the molecular mechanism of mucosal immunity of fish during bacterial challenge, a de novo transcriptome assembly of crucian carp Carassius auratus skin upon Aeromonas hydrophila infection was performed, the latter with Illumina Hiseq 2000 platform. A total of 118111 unigenes were generated and of these, 9693 and 8580 genes were differentially expressed at 6 and 12 h post-infection, respectively. The validity of the transcriptome results of eleven representative genes was verified by quantitative real-time PCR (qRT-PCR) analysis. A comparison with the transcriptome profiling of zebrafish skin to A. hydrophila with regards to the mucosal immune responses revealed similarities in the complement system, chemokines, heat shock proteins and the acute-phase response. GO and KEGG enrichment pathway analyses displayed the significant immune responses included TLR, MAPK, JAK-STAT, phagosome and three infection-related pathways (ie., Salmonella, Vibrio cholerae and pathogenic Escherichia coli) in skin. To our knowledge, this study is the first to describe the transcriptome analysis of C. auratus skin during A. hydrophila infection. The outcome of this study contributed to the understanding of the mucosal defense mechanisms in cyprinid species.
Evaluation of antiarthritic activity of nimbolide against Freund's adjuvant induced arthritis in rats

Cui X, Wang R, Bian P, Wu Q, Seshadri VDD, Liu L

Artif Cells Nanomed Biotechnol, 2019 Dec;47(1):3391-3398.
PMID: 31394949 DOI: 10.1080/21691401.2019.1649269

Nimbolide, a triterpenoid isolated from flower of neem tree possess various therapeutic properties. The objective of the study was to assess the anti-arthritic activity of nimbolide in arthritis induced rats. Nimbolide (20 mg/kg per day) was given orally to arthritic rats induced with Complete Freund's Adjuvant and changes in paw volume, body weight, organ indices (thymus and spleen), arthritic score, biochemical parameters and proinflammatory cytokines levels were determined. Histopathological analysis was also performed. Western blot analysis was also performed. Rats treated with nimbolide displayed marked reduction in arthritic score, organ indices, volume of paw, edema formation, along with substantial enhancement in body weight. Histopathological findings showed significant reduction in destruction of joints and inflammation following nimbolide treatment. The protective action of arthritic rats treated with nimbolide was also substantiated by molecular and biochemical studies. The results of the study show that nimbolide treatment has markedly enhanced health and reduced inflammation via lessening the proinflammatory cytokines expression in arthritic rats. Hence, nimbolide may be used as a potent therapeutic drug in treating rheumatoid arthritis.
Elucidation of stoichiometric efficiency, radical generation and transformation pathway during catalytic oxidation of sulfamethoxazole via peroxymonosulfate activation

Bao Y, Oh WD, Lim TT, Wang R, Webster RD, Hu X

Water Res, 2019 03 15;151:64-74.
PMID: 30594091 DOI: 10.1016/j.watres.2018.12.007

In this work, nano-bimetallic Co/Fe oxides with different stoichiometric Co/Fe ratios were prepared using a novel one-step solution combustion method. The nano-bimetallic Co/Fe oxides were used for sulfamethoxazole (SMX) degradation via peroxymonosulfate (PMS) activation. The stoichiometric efficiencies of the as-prepared nano-bimetallic catalysts were calculated and compared for the first time. The radical generation was identified by electron paramagnetic resonance (EPR) as well as chemical quenching experiments, in which different scavengers were used and compared. The catalytic PMS activation mechanism in the presence of catalyst was examined by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results showed that besides SO4•- and •OH, •OOH was also detected in the PMS/CoFeO2.5 system. Meanwhile, in addition to the previously proposed radical oxidation pathway, the results showed that SMX degradation also involved a non-radical oxidation, which could be verified by the degradation experiment without catalyst as well as the detection of 1O2. In the PMS activation process, cobalt functioned as the active site on CoFeO2.5 while Fe oxide functioned as the adsorption site. The electron transfer mechanism was proposed based on the XPS and metal leaching results. Additionally, via the detection of transformation products, different SMX transformation pathways involving nitration, hydroxylation and hydrolysis in the PMS/CoFeO2.5 system were proposed.
Oxidative torrefaction performance of microalga Nannochloropsis Oceanica towards an upgraded microalgal solid biofuel

Zhang C, Ho SH, Chen WH, Wang R, Show PL, Ong HC

J Biotechnol, 2021 Sep 10;338:81-90.
PMID: 34298023 DOI: 10.1016/j.jbiotec.2021.07.009

Microalgae are a promising feedstock for carbon-neutral biofuel production due to their superior cellular composition. Alternatively, oxidative torrefaction has been recognized as a potential thermochemical technique for microalgal solid biofuel upgrading. Herein, by using microalga N. oceanica as a feedstock, several characterizations are adopted for evaluating the potential of oxidative torrefaction towards microalgal solid biofuel production. The oxidatively torrefied microalgae can be upgraded as lignite. After in-depth analysis, significant change in the surface microstructure of oxidatively torrefied microalgae is largely changed (via wrinkle and fragmentation) The hydrophobicity, thermal decomposition, thermal stability, and aromatization of oxidatively torrefied microalgae can be largely enhanced as the oxidative torrefaction severity increase. With the increasing torrefaction temperature, the hydrophobicity of oxidative torrefied microalgae gradually improved. The decomposition of C-2/3/5, and -OCH3, the CO bonds of CH3CO-, and the aromatization occurs via oxidative torrefaction according to the NMR analysis. For XPS analysis, torrefaction operation significantly decreases the carbide carbon and enhances the graphitization. As a result, the thermal stability of oxidatively torrefied microalgae is improved. Conclusively, the information obtained in this study can provide insights into the evaluation of oxidative torrefaction performance and fuel properties of microalgal solid biofuel, which may help accelerate the advancement of oxidative torrefaction industrialization.
[Laboratory diagnosis and molecular tracing of dengue bordline cases in Henan Province, 2017]

Du YH, Li Y, Wang RL, Wang HF, Su J, Xu BL, et al.

Zhonghua Yu Fang Yi Xue Za Zhi, 2018 Nov 06;52(11):1164-1167.
PMID: 30419702 DOI: 10.3760/cma.j.issn.0253-9624.2018.11.013

Objective: To confirm the laboratory diagnosis of dengue bordline cases reported in Henan Province and trace its origin from molecular level in 2017. Methods: The study samples were blood samples (3-5 ml), which came from 8 suspected cases of dengue fever reported in the 2017 direct reporting system of Henan provincial infectious disease monitoring network. Meanwhile, case investigation was conducted according to National dengue fever surveillance programme. Serum were separated from blood samples and tested for Dengue NS1 antigen, IgM & IgG antibodies, and dengue RNA. According to dengue diagnosis criteria, confirmed cases were identified by testing results. Samples carried dengue RNA performed for real-time PCR genotyping and amplification of E gene. Then, the amplicons were sequenced and homological and phylogenetic analyses were constructed. Results: 8 serum samples of suspected dengue cases were collected in Henan Province, 2017. Six of them were diagnosed as dengue confirmed cases. All the dengue confirmed cases belonged to outside imported cases, 5 of them were positive by dengue RNA testing. Genotyping results showed there were 1 DENV1 case, 2 DENV2 cases and 2 DENV3 cases. A DENV2 case and a DENV3 case of this study were traced its origin successfully. The sequence of Pakistan imported DENV2 case belongs to cosmopolitan genotype, which was the most consistent with Pakistan's DENV2 KJ010186 in 2013 (identity 99.0%). The sequence of Malaysia imported DENV3 case belongs to genotype I, which was the most consistent with Singapore's DENV3 KX224276 in 2014(identity 99.0%). Conclusion: The laboratory diagnosis and molecular traceability of dengue cases in Henan Province in 2017 confirmed that all cases were imported and did not cause local epidemics.
Analysis of meteorological dryness/wetness features for spring wheat production in the Ili River basin, China

Li C, Wang R, Xu J, Luo Y, Tan ML, Jiang Y

Int J Biometeorol, 2018 Dec;62(12):2197-2204.
PMID: 30368677 DOI: 10.1007/s00484-018-1623-2

Understanding the impacts of climate change on crop yield is important for improving crop growth and yield formation in northwestern China. In this study, we evaluated the relationship between meteorological dryness/wetness conditions and spring wheat yield in the Ili river basin (IRB). The climate and yield data from 1961 to 2013 were collected to analyze characteristics and correlations between these two variables using the standardized precipitation evapotranspiration index (SPEI), yield detrending method, modified Mann-Kendall test and Spearman correlation analysis. Main results were as follows: (1) correlations between monthly SPEI values (MSV) and climatic yield of spring wheat indicated that the dryness/wetness condition in May was a key factor affecting yield in the whole region; (2) although the MSV in May and yield fluctuated from negative to positive values in time, the severely and extremely dryness events were in good agreement with the higher yield losses; (3) each increase of 0.5 MSV in May promoted over 3% increase of yield in most part of IRB; however, the larger variability of MSV in May resulted in larger yield fluctuations; and (4) the Tibetan Plateau index in April showed significant correlations with the MSV in May and yield, which provided a precursory signal for decision-makers to better understand potential yield fluctuations.
Fulltext Neuroprotective effect of YIAEDAER peptide against Parkinson's disease like pathology in zebrafish

Ren Q, Jiang X, Zhang S, Gao X, Paudel YN, Zhang P, et al.

Biomed Pharmacother, 2022 Mar;147:112629.
PMID: 35030435 DOI: 10.1016/j.biopha.2022.112629

Parkinson's disease (PD) is characterized by the loss of dopaminergic (DA) neurons in the substantia nigra (SN) and aggregation of α-synuclein (α-syn). Current PD therapies merely provide symptomatic relief, lacking the disease-modifying therapeutic strategies against that could reverse the ongoing neurodegeneration. In the quest of exploring novel disease modifying therapeutic strategies, compounds from natural sources have gained much attention in recent days. YIAEDAER (Tyr-Ile-Ala-Glu-Asp-Ala-Glu-Arg) peptide is a multi-functional peptide isolated and purified from the visceral mass extract of Neptunea arthritica cumingii (NAC) with plethora of pharmacological activities, however its neuroprotective effect against MPTP induced PD model is not yet reported. We found YIAEDAER peptide co-treatment could suppressed the MPTP-induced locomotor impairment in zebrafish, ameliorates the MPTP induced degeneration of DA neurons, inhibited the loss of vasculature and loss of cerebral vessels, suppressed α-syn levels. Moreover, YIAEDAER peptide modulates several genes related to autophagy (α-syn, pink1, parkin, atg5, atg7, beclin1, ulk1b, ulk2, and ambra1a), and oxidative stress (sod1, sod2, gss, gpx4a, gsto2, and cat). Hence, our finding suggests that YIAEDAER peptide might be a potential therapeutic candidate against MPTP-induced PD like condition.
Fulltext Rare Species Shift the Structure of Bacterial Communities Across Sphagnum Compartments in a Subalpine Peatland

Tian W, Xiang X, Ma L, Evers S, Wang R, Qiu X, et al.

Front Microbiol, 2019;10:3138.
PMID: 32038572 DOI: 10.3389/fmicb.2019.03138

Sphagnum-associated microbiomes are crucial to Sphagnum growth and peatland ecological functions. However, roles of rare species in bacterial communities across Sphagnum compartments are poorly understood. Here the structures of rare taxa (RT) and conditionally abundant and rare taxa (CART) from Sphagnum palustre peat (SP), S. palustre ectosphere (Ecto) and S. palustre endosphere (Endo) were investigated in the Dajiuhu Peatland, central China. Our results showed that plant compartment effects significantly altered the diversities and structures of bacterial communities. The Observed species and Simpson indices of RT and CART in alpha diversity significantly increased from Endo to SP, with those of Ecto in-between. The variations of community dissimilarities of RT and CART among compartments were consistent with those of whole bacterial communities (WBC). Network analysis indicated a non-random co-occurrence pattern of WBC and all keystone species are affiliated with RT and CART, indicating their important role in sustaining the WBC. Furthermore, the community structures of RT and CART in SP were significantly shaped by water table and total nitrogen content, which coincided with the correlations between WBC and environmental factors. Collectively, our results for the first time confirm the importance of rare species to bacterial communities through structural and predicted functional analyses, which expands our understanding of rare species in Sphagnum-associated microbial communities in subalpine peatlands.
Ameliorative effect of Gastrodia elata Blume extracts on depression in zebrafish and cellular models through modulating reticulon 4 receptors and apoptosis

Wang R, Ren Q, Gao D, Paudel YN, Li X, Wang L, et al.

J Ethnopharmacol, 2022 Jan 29;289:115018.
PMID: 35092824 DOI: 10.1016/j.jep.2022.115018

ETHNOPHARMACOLOGICAL RELEVANCE: Gastrodia elata Blume (G. elata), a traditional Chinese herb, known as "Tian Ma", is widely used as a common medicine and diet ingredient for treating or preventing neurological disorders for thousands of years in China. However, the anti-depressant effect of G. elata and the underlying mechanism have not been fully evaluated.
AIM OF THE STUDY: The study is aimed to investigate the anti-depressant effect and the molecular mechanism of G. elata in vitro and in vivo using PC12 cells and zebrafish model, respectively.
MATERIAL AND METHODS: Network pharmacology was performed to explore the potential active ingredients and action targets of G. elata Blume extracts (GBE) against depression. The cell viability and proliferation were determined by MTT and EdU assay, respectively. TUNEL assay was used to examine the anti-apoptotic effect of GBE. Immunofluorescence and Western blot were used to detect the protein expression level. In addition, novel tank diving test was used to investigate the anti-depressant effect in zebrafish depression model. RT-PCR was used to analyze the mRNA expression levels of genes.
RESULTS: G. elata against depression on the reticulon 4 receptors (RTN4R) and apoptosis-related targets, which were predicted by network pharmacology. Furthermore, GBE enhanced cell viability and inhibited the apoptosis in PC12 cells against CORT treatment. GBE relieved depression-like symptoms in adult zebrafish, included increase of exploratory behavior and regulation of depression related genes. Mechanism studies showed that the GBE inhibited the expression of RTN4R-related and apoptosis-related genes.
CONCLUSION: Our studies show the ameliorative effect of G. elata against depression. The mechanism may be associated with the inhibition of RTN4R-related and apoptosis pathways.
Preparation and characterization of bioplastics from silylated cassava starch and epoxidized soybean oils

Yang J, Xu S, Wang W, Ran X, Ching YC, Sui X, et al.

Carbohydr Polym, 2023 Jan 15;300:120253.
PMID: 36372510 DOI: 10.1016/j.carbpol.2022.120253

In this work, a systematic coupling study of silane coupling agent between starch and epoxidized soybean oils (ESO) was carried out. Starch was modified by 3-aminopropyl trimethoxy silane (APMS) with various contents of NaOH. The APMS-modified starch was incorporated with ESO to synthesize the bioplastics by solution casting. As demonstrated by the FTIR spectra, the hydrogen bond interactions among starch molecules were inhibited by the modification. This outcome provided higher interaction and compatibility of starch with ESO, as confirmed by FESEM. TGA showed that the thermal stability of starch decreased considerably after the silylation. In contrast, the produced bioplastics with silylated starch exhibited higher thermal stability than the control sample. Regarding the bioplastics, an obvious increase of tensile strength from 5.78 MPa to 9.29 MPa was obtained. This work suggested a simple and effective modification technique by APMS to improve compatibility of starch/ESO-based bioplastics with superior mechanical and thermal properties.
Eimeria infections of plateau pika altered the patterns of temporal alterations in gut bacterial communities

Li M, Wang S, Zhong L, Heděnec P, Tan Z, Wang R, et al.

Front Microbiol, 2023;14:1301480.
PMID: 38274745 DOI: 10.3389/fmicb.2023.1301480

Intestinal parasites, such as Eimeria, are common among plateau pika (Ochotona curzoniae). The gut microbiome is an essential driver of the host response to gastrointestinal parasites. However, the effects of intestinal protozoal parasites on the temporal variations in the gut microbiome and behavioral and physiological activities remain unknown. Our study conducted treatments involving experimental feeding of pika with Eimeria oocysts or anticoccidia under laboratory conditions to focus on the parasite-associated alterations in gut bacterial communities, host behavioral activity, physiology, and host-bacteria relationships. The results showed insignificant differences in bacterial community structures among treatments on the basis of Bray-Curtis distance metrics, whereas the patterns of temporal alterations in the bacterial communities were changed by the treatments. Bacterial alpha diversities did not vary with the treatments, and experimental feeding with Eimeria slowed down the decrement rate of alpha diversity. Furthermore, few bacterial members were significantly changed by the treatments-only the genus Ruminococcus and the species Ruminococcus flavefaciens, which were associated with energy metabolism. Experimental feeding with Eimeria modified the temporal variations in the bacterial members, including a lower loss rate of the relative abundance of the dominant families Muribaculaceae and Ruminococcaceae in the group with Eimeria experimental feeding. Moreover, a shifting energy trade-off was suggested by the parasite-induced increments in thyroid hormones (triiodothyronine and tetraiodothyronine) and decrements in exploration behavior in the group with Eimeria feeding. However, we did not detect specific connections between gut bacterial communities and pika behaviors and physiology in terms of energy trade-offs. Further in-depth research is needed to examine the role of Eimeria-modified differences in the gut bacteria of plateau pika.
Fulltext Efficacy of Progressive Muscle Relaxation in Adults for Stress, Anxiety, and Depression: A Systematic Review

Muhammad Khir S, Wan Mohd Yunus WMA, Mahmud N, Wang R, Panatik SA, Mohd Sukor MS, et al.

Psychol Res Behav Manag, 2024;17:345-365.
PMID: 38322293 DOI: 10.2147/PRBM.S437277

BACKGROUND: The rise in the prevalence of mental health problems among adults worldwide has raised concerns, highlighting the critical need for evidence-based mental health interventions that are accessible, comprehensive, and effective. Previous research suggests that Progressive Muscle Relaxation (PMR) is a promising intervention widely used to reduce mental health problems. Nevertheless, the current literature on the efficacy of PMR among adults globally is fragmented, indicating a potential gap in this research area. Hence, this paper aims to systematically compile the research evidence on the efficacy of PMR in adults for stress, anxiety, and depression.
METHODS: The Scopus, Web of Sciences, PubMed, PsycINFO, and Cochrane Central Register of Controlled Trials were searched from the earliest available evidence to 28th March 2023. The PRISMA (Preferred Reporting Items of Systematic Reviews and Meta-analyses) guidelines were followed, and the protocol was registered on the Open Science Framework. Joanna Briggs Institute (JBI) Critical Appraisal Tools were used to assess the quality of the included studies.
RESULTS: A total of forty-six (46) publications from sixteen (16) countries covering more than 3402 adults were included in the review. The results show that PMR are effective in reducing stress, anxiety, and depression in adults. When PMR is combined with other interventions, the combined techniques have also consistently exhibited enhanced efficacy. Moreover, findings also indicate that the efficacy of PMR is heightened when implemented in conjunction with other interventions, surpassing its standalone efficacy.
FUNDING AND REGISTRATION: This research was supported/funded by the Ministry of Higher Education (MoHE) under the Fundamental Research Grant Scheme (FRGS) (FRGS/1/2020/SS0/UTM/02/23). The review was registered on Open Science Framework (OSF) on the 7th of March 2023; DOI: https://doi.org/10.17605/OSF.IO/U2HZP.
Influence of starch silylation on the structures and properties of starch/epoxidized soybean oil-based bioplastics

Yang J, Xu S, Chee CY, Ching KY, Wei Y, Wang R, et al.

Int J Biol Macromol, 2024 Feb;258(Pt 2):129037.
PMID: 38158061 DOI: 10.1016/j.ijbiomac.2023.129037

The present work systematically investigated the influence of starch silylation on the structures and properties of starch/epoxidized soybean oil-based bioplastics. Silylated starch was synthesized using starch particles (SP-ST) or gelatinized starch (SG-ST) under different silane hydrolysis pHs. Due to the appearance of -NH2 groups and lower OH wavenumbers, SP-ST obtained at pH 5 showed higher silylation degree and stronger hydrogen bond interaction with epoxidized soybean oils (ESO) than that at pH 11. The morphology analysis revealed better interfacial compatibility of ESO and SP-ST. The tensile strength of the samples containing SP-ST increased by 51.91 % than the control, emphasizing the enhanced interaction within the bioplastics. However, tensile strength of the bioplastics with SG-ST decreased by 59.56 % due to their high moisture contents from unreacted silanes. Additionally, the bioplastics with SG-ST exhibited an obvious reduction of thermal stability and an increase in water solubility because of the presence of unreacted APMS. The bioplastic degradation was not prevented by starch silylation except high pH. The bioplastics showed the most desirable tensile properties, thermal stability, and water solubility when starch was surface-modified with silanes hydrolyzed at pH 5. These outcomes made the fabricated bioplastics strong candidates for petroleum-based plastics for packaging applications.
Fulltext Phytochemicals from fern species: potential for medicine applications

Cao H, Chai TT, Wang X, Morais-Braga MFB, Yang JH, Wong FC, et al.

Phytochem Rev, 2017;16(3):379-440.
PMID: 32214919 DOI: 10.1007/s11101-016-9488-7

Ferns are an important phytogenetic bridge between lower and higher plants. Historically they have been used in many ways by humans, including as ornamental plants, domestic utensils, foods, and in handicrafts. In addition, they have found uses as medicinal herbs. Ferns produce a wide array of secondary metabolites endowed with different bioactivities that could potentially be useful in the treatment of many diseases. However, there is currently relatively little information in the literature on the phytochemicals present in ferns and their pharmacological applications, and the most recent review of the literature on the occurrence, chemotaxonomy and physiological activity of fern secondary metabolites was published over 20 years ago, by Soeder (Bot Rev 51:442-536, 1985). Here, we provide an updated review of this field, covering recent findings concerning the bioactive phytochemicals and pharmacology of fern species.
Fulltext Loss-free tensile ductility of dual-structure titanium composites via an interdiffusion and self-organization strategy

Liu L, Li S, Pan D, Hui D, Zhang X, Li B, et al.

Proc Natl Acad Sci U S A, 2023 Jul 11;120(28):e2302234120.
PMID: 37399391 DOI: 10.1073/pnas.2302234120

The deformation-coordination ability between ductile metal and brittle dispersive ceramic particles is poor, which means that an improvement in strength will inevitably sacrifice ductility in dispersion-strengthened metallic materials. Here, we present an inspired strategy for developing dual-structure-based titanium matrix composites (TMCs) that achieve 12.0% elongation comparable to the matrix Ti6Al4V alloys and enhanced strength compared to homostructure composites. The proposed dual-structure comprises a primary structure, namely, a TiB whisker-rich region engendered fine grain Ti6Al4V matrix with a three-dimensional micropellet architecture (3D-MPA), and an overall structure consisting of evenly distributed 3D-MPA "reinforcements" and a TiBw-lean titanium matrix. The dual structure presents a spatially heterogeneous grain distribution with 5.8 μm fine grains and 42.3 μm coarse grains, which exhibits excellent hetero-deformation-induced (HDI) hardening and achieves a 5.8% ductility. Interestingly, the 3D-MPA "reinforcements" show 11.1% isotropic deformability and 66% dislocation storage, which endows the TMCs with good strength and loss-free ductility. Our enlightening method uses an interdiffusion and self-organization strategy based on powder metallurgy to enable metal matrix composites with the heterostructure of the matrix and the configuration of reinforcement to address the strength-ductility trade-off dilemma.

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links