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Fight them or feed them:how the intestinal mucus layer manages the gut microbiota

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Gastroenterology Report 2019年第1期7卷 3-12,I0001页

作者： Bjoern o.Schroeder Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research Department of Molecular and Clinical MedicineInstitute of MedicineBruna Stra°ket 16University of GothenburgSE 41345 GothenburgSweden

The intestinal tract is inhabited by a tremendous number of microorganisms,termed the gut *** microorganisms live in a mutualistic relationship with their host and assist in the degradation of complex *** the gut microbiota is generally considered beneficial,the vast number of microbial cells also form a permanent threat to the ***,the intestinal epithelium is covered with a dense layer of mucus to prevent translocation of the gut microbiota into underlying *** mucus is an organized glycoprotein network with a host-specific glycan *** the mucus layer has long been considered a passive,host-designed barrier,recent studies showed that maturation and function of the mucus layer are strongly influenced by the gut *** return,the glycan repertoire of mucins can select for distinct mucosa-associated bacteria that are able to bind or degrade specific mucin glycans as a nutrient *** the intestinal mucus layer is at the crucial interface between host and microbes,its breakdown leads to gut bacterial encroachment that can eventually cause inflammation and ***,a dysfunctional mucus layer has been observed in colitis in mice and ***,the increased consumption of a low-fiber Western-style diet in our modern society has recently been demonstrated to cause bacteria-mediated defects of the intestinal mucus ***,I will review current knowledge on the interaction between gut bacteria and the intestinal mucus layer in health and *** the molecular details of this host–microbe interaction may contribute to the development of novel treatment options for diseases involving a dysfunctional mucus layer,such as ulcerative colitis.

关键词： Dietary fiber gut microbiota host-microbe interaction inflammatory bowel disease mucus mucin mucosal barrier metabolic disease probiotics ulcerative colitis

Anaerobic digestion of cyanobacteria and chlorella to produce methane for biofuel

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International Journal of Agricultural and Biological Engineering 2012年第3期5卷 68-74页

作者： Abiodun o.Jegede Centre for Energy Research and Development Obafemi Awolowo UniversityIle-IfeOsunNigeria

The methane potentials of cyanobacteria and chlorella have been investigated in eight different lab scale reactors at 25℃for three-day Hydraulic Retention Time(HRT).Autoclavation pre-treatment was applied to the cyanobacteria to aid digestion,while the Chlorella was obtained and digested in powdery *** organic loading rates were 1g VS,2 g VS,3 g VS,4 g VS,5 g VS,6 g VS,7 g VS,8 g VS and 9 g *** production rates increased with increasing loading rates and started declining at loading rate higher than 7 g VS,while the HRT was kept *** highest methane production rates for cyanobacteria and chlorella were(78±25)mL/(L·d)and(100±25)mL/(L·d),respectively,at loading rate of 7 g *** instability occurred at loading rates of 8 g VS and 9 g VS with higher accumulation of methane *** compositions of both feeds were close and the methane production potentials of both biomasses were also close and followed the same trend.

关键词： anaerobic digestion biofuel carbon dioxide(Co2) Hydraulic Retention Time(HRT) methane(CH4) chemical oxygen demand(CoD) volatile fatty acids(VFAs)

Indentation Size Effect and Microhardness Study of β-Sn Single Crystals

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Chinese Physics Letters 2005年第12期22卷 3137-3140页

作者： o. SAHIN o. UZUN U. KoLEMEN B. DUZGUN N. UCAR Department of Physics Art and Science Faculty Suleyman Demirel University Isparta Turkey Department of Physics Art and Science Faculty Gaziosmanpasa University Tokat Turkey Department of Physics K. K. Education Faculty Ataturk-University Erzurum Turkey

The load dependence of apparent microhardness of β-Sn single crystals having different growth directions is investigated. The measurements are performed on （110） planes of these crystals in the load range from 10 to 50 mN. It is found that the degree of the microhardness anisotropy decreases for higher indentation test loads. The examined materials exhibit the behaviour of indentation size effect （ISE）, i.e., the apparent hardness increases with decreasing indentation load. Neither Meyer＇s law nor the proportional specimen resistance （PSR） model can fully explain the nonlinear variation of microhardness with load. Instead, preference is given to modified the PSR model based on the consideration of the effect of machining-induced residually stressed surface on the hardness measurement.

关键词： CoBALT-BASED ALLoYS SILICoN-NITRIDE STRUCTURAL-PRoPERTIES KNooPMICRoHARDNESS BASAL-PLANE HARDNESS CERAMICS ANISoTRoPY PRESSURE SoLIDS

o_(3) based advanced oxidation for ibuprofen degradation

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Chinese Journal of Chemical Engineering 2022年第2期35卷 277-284页

作者： Vitória M.Almeida Carla A.orge M.Fernando R.Pereira o.SaloméG.P.Soares Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and Materials (LSRE-LCM)Faculdade de Engenharia da Universidade do PortoRua Dr.Roberto Frias4200-465 PortoPortugal

The degradation of the anti-inflammatory ibuprofen(IBP)was evaluated by several advanced oxidation *** was treated by single ozonation and oxidation with hydrogen peroxide(H_(2)o_(2)),as well as a combination of these *** order to improve the efficiency,the presence of catalysts such as original carbon nanotubes,labelled as CNT,and iron oxide supported on carbon nanotubes,named as Fe/CNT sample,was *** evolution of IBP degradation,mineralization and toxicity of the solutions was *** formation of intermediates was also *** the non-catalytic processes,IBP was faster removed by single ozonation,whereas no significant total organic carbon(ToC)removal was *** with H_(2)o_(2) did not present satisfactory *** ozone and H_(2)o_(2) were combined,a higher mineralization was attained(70%after 180 min of reaction).on the other hand,in the catalytic processes,this combined process allowed the fastest IBP *** terms of mineralization degree,the presence of Fe/CNT increases the removal rate in the first hour of reaction,achieving a ToC removal of 85%.Four compounds were detected as *** treated solutions presented lower toxicity than the initial solution,suggesting that the released intermediates during applied processes are less toxic.

关键词： Advanced oxidation processes Catalysts Emerging pollutants Ibuprofen

Metal organic Chemical Vapour Deposited Thin Films of Cobalt oxide Prepared via Cobalt Acetylacetonate

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Journal of Materials Science & Technology 2009年第1期25卷 85-89页

作者： C.U. Mordi M.A. Eleruja B.A. Taleatu G.o. Egharevba A.V. Adedeji o.o. Akinwunmi B. olofinjana C. Jeynes E.o.B. Ajayi Department of Physics Obafemi Awolowo University Ile-Ife Nigeria Department of Chemistry Obafemi Awolowo University Ile-Ife Nigeria Department of Physics Auburn University Alabama United States Department of Electronics and Electrical Engineering University of Surrey Guildford Surrey GU2 7XH UK

The single solid source precursor, cobalt （Ⅱ） acetylacetonate was prepared and characterized by infrared spectroscopy. Thin films of cobalt oxide were deposited on soda lime glass substrates through the pyrolysis （metal organic chemical vapour deposition （MoCVD）） of single solid source precursor, cobalt acetylacetonate, Co[C5H7o2]2 at a temperature of 420℃. The compositional characterization carried out by rutherford backscattering spectroscopy and X-ray diffraction （XRD）, showed that the films have a stoichiometry of Co2o3 and an average thickness of 227±0.2 nm. A direct energy gap of 2,15±0.01 eV was calculated by the data obtained by optical absorption spectroscopy. The morphology of the films obtained by scanning electron microscopy, showed that the grains were continuous and uniformly distributed at various magnifications, while the average grain size was less than i micron for the deposited thin films of cobalt oxide.

关键词： Precursor Thin film oxide Metal organic chemical vapour deposition (MoCVD) Rutherford backscattering spectroscopy (RBS)

Biotechnology of the multipurpose tree species Arbutus unedo:a review

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Journal of Forestry Research 2022年第2期33卷 377-390页

作者： João Martins Glória Pinto Jorge Canhoto Centre for Functional Ecology Department of Life SciencesUniversity of CoimbraCoimbraPortugal Centre for Environmental and Marine Studies Department of BiologyUniversity of AveiroAveiroPortugal

Arbutus unedo L.(strawberry tree,Ericaceae)is a woody species with a circum-Mediterranean *** has considerable ecological relevance in southern European forests due to its resilience to abiotic and biotic *** edible red berries are used in the production of traditional products,including an expensive *** compounds extracted from the species have bioactive prop-erties used by the cosmetic and pharmaceutical *** strawberry tree has gone from a neglected species to become a highly valuable crop with large cultivated areas in southern European and North African *** to an increasing demand from farmers for plants with improved features,researchers have been trying to improve this spe-cies through conventional and biotechnological tools,focus-ing mainly on population analysis using molecular markers,in vitro cloning,tolerance to biotic and abiotic stresses,and intraspecific crosses to obtain genotypes with new *** objective of this review is to gather and update information about the species and make it available to researchers and *** research areas that are considered a priority for this species are highlighted.

关键词： Breeding Chemical profiling Ericaceae Microbiome Micropropagation

Synergy between thermal and nonthermal effects in plasmonic photocatalysis

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Nano Research 2020年第5期13卷 1268-1280页

作者： Xueqian Li Henry o.Everitt Jie Liu Department of Chemistry Duke UniversityDurhamNC 27708USA 2 U.S.Army Combat Capabilities Development CommandAviation&Missile CenterRedstone ArsenalAL 35898USA Department of Physics Duke UniversityDurhamNC 27708USA Present address:Department of Applied Physics and Materials Science California Institute of TechnologyPasadenaCA 91125USA

Plasmonic photocatalysis represents the synergetic union of two active fields of research:plasmonic effects in illuminated metallic nanoparticles and catalytic effects in tailored metallic ***,metallic nanoparticles that excel for one application are limited for the other,but recent developments have shown that desirable catalytic behaviors,such as reduced activation barriers and improved product selectivity,derive from nonthermal behaviors uniquely produced by this *** examining such findings,this review will address a specific debate that has recently surfaced:what is the relative degree of contributions of thermal and nonthermal effects in plasmonic photocatalysis?We demonstrate the importance of correctly accounting for thermal effects before characterizing nonthermal *** show that another synergy occurs:these desirable nonthermal behaviors have a temperature dependence,and the resulting temperature-dependent reaction rates far exceed what can be explained from purely thermal effects ***,the synergy of plasmonic photocatalysis offers an exciting new contribution to the quest for efficient,selective,sustainable methods for chemical synthesis and energy conversion.

关键词： plasmonic catalysis hot carriers photothermal catalysis localized surface plasmon

Do DBPs swim in salt water pools? Comparison of 60 DBPs formed by electrochemically generated chlorine vs. conventional chlorine

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Journal of Environmental Sciences 2022年第7期34卷 232-241页

作者： Caroline o.Granger Susan D.Richardson Department of Chemistry and Biochemistry University of South Carolina631 Sumter St.ColumbiaSC 29208USA

Disinfectants are added to swimming pools to kill harmful pathogens. Although liquid chlorine(sodium hypochlorite) is the most commonly used disinfectant, alternative disinfection techniques like electrochemically generated mixed oxidants or electrochemically generated chlorine, often referred to as salt water pools, are growing in popularity. However, these disinfectants react with natural organic matter and anthropogenic contaminants introduced to the pool water by swimmers to form disinfection byproducts(DBPs). DBPs have been linked to several adverse health effects, such as bladder cancer, adverse birth outcomes, and asthma. In this study, we quantified 60 DBPs using gas chromatography-mass spectrometry and assessed the calculated cytotoxicity and genotoxicity of an indoor community swimming pool before and after switching to a salt water pool with electrochemically generated chlorine. Interestingly, the total DBPs increased by 15% upon implementation of the salt water pool, but the calculated cytotoxicity and genotoxicity decreased by 45% and 15%, respectively. Predominant DBP classes formed were haloacetic acids, with trichloroacetic acid and dichloroacetic acid contributing 57% of the average total DBPs formed. Haloacetonitriles, haloacetic acids, and haloacetaldehydes were the primary drivers of calculated cytotoxicity, and haloacetic acids were the primary driver of calculated genotoxicity. Diiodoacetic acid, a highly toxic iodinated DBP, is reported for the first time in swimming pool water. Bromide impurities in sodium chloride used to electrochemically generate chlorine led to a 73% increase in brominated DBPs, primarily driven by bromochloroacetic acid. This study presents the most extensive DBP study to-date for salt water pools.

关键词： Disinfection byproducts Swimming pools Cytotoxicity Genotoxicity GC-MS

Antimotility effects of extracts and fractions of Eastern Nigeria mistletoe(Loranthus micranthus Linn)

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Asian Pacific Journal of Tropical Medicine 2012年第7期5卷 556-560页

作者： Patience o osadebe Chika C Abba Matthias o Agbo Department of Pharmaceutical and Medicinal Chemistry University of NigeriaNsukkaEnugu StateNigeria

objective:To evaluate the antimotility activity of Eastern Nigerian mistletoe[Loranthus micranthus（***） Linn]parasitic on six different host trees *** nitida,Persia americana,Kola accuminata,Irvingia gabonensis,Citrus simensis and Pentacletra macrophylla （***）.Methods:The antimotility of the methanol extracts and solvent fractions were evaluated in castor oil induced diarrheoa in ***:The methanol extracts（200 mg/kg, i.p.） inhibited defeacation significantly（P on（75.73%to 93.33%） more than that of atropine sulphate（2 mg/kg,i.p.） which inhibited defeacation by 80.0%.The methanol extract（200 mg/kg,i.p.） of L micranthus parasitic on *** exhibited significant（Pon in gastrointestinal transit（67.6%） more than that of atropine sulphate（2 mg/kg,Lp.） which inhibited gastrointestinal transit by 26.4%.The solvent fractions of L micranthus parasitic on *** at dose levels of 150 mg/kg inhibited significantly the gastrointestinal transit of *** F5 exhibited inhibitory activity which was comparable to loperamide（73.3%）. Conclusions:The methanol extract of L micranthus parasitic on *** exhibits higher antimotility activity that other *** solvent fractions could serve as source of novel antimotility agents.

关键词： Loranthus micranthus Fractination Gastrointestinal transit Atropine