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Influence of coagulation mechanisms and floc formation on filterability

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Journal of Environmental Sciences 2017年第7期29卷 338-345页

作者： Ruyuan Jiao Rolando Fabris Christopher W.K.Chow Mary Drikas john van Leeuwen Dongsheng Wang Zhizhen Xu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of Sciences Australian Water Quality Centre South Australian Water Corporation Centre for Water Management and Reuse School of Natural and Built EnvironmentsUniversity of South Australia Key Laboratory of Occupational Safety and Health Beijing Municipal Institute of Labor Protection

Minimizing particles in water is a key goal for improving drinking water quality and *** media filtration process,as the last step of the solid–liquid separation process,is largely influenced by the characteristics of flocs,which are formed and controlled within the coagulation *** a laboratory-based study,the impacts of the physical characteristics of flocs formed using aluminum sulfate on the filtration treatment of two comparative water samples were investigated using a photometric dispersion analyzer and a filterability *** general,the optimum dosage for maximizing filterability was higher than that for minimizing turbidity under neutral p H *** a monomeric aluminum-based coagulant,the charge neutralization mechanism produced better floc characteristics,including floc growth speed and size,than the sweep flocculation *** addition,the charge neutralization mechanism showed better performance compared to sweep flocculation in terms of DOC removal and floc filterability improvement for both waters,and showed superiority in turbidity removal only when the raw water had high *** the different mechanisms,the ways that floc characteristics impacted on floc filterability also *** low variation in floc size distribution obtained under the charge neutralization mechanism resulted in the flocs being amenable to removal by filtration *** the sweep flocculation mechanism,increasing the floc size improved the settling ability of flocs,resulting in higher filter efficiency.

关键词： Coagulation mechanisms Floc characteristics Filterability Turbidity

Developing a chloramine decay index to understand nitrification:A case study of two chloraminated drinking water distribution systems

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Journal of Environmental Sciences 2017年第7期29卷 170-179页

The management of chloramine decay and the prevention of nitrification are some of the critical issues faced by water utilities that use chloramine as a *** this study,potential association between high performance size exclusion chromatography（HPSEC）data obtained with multiple wavelength Ultraviolet（UV） detection from two drinking water distribution systems in Australia and nitrification occurrence was *** increase in the absorbance signal of HPSEC profiles with UV detection at λ = 230 nm between apparent molecular weights of 200 to 1000 Da was observed at sampling sites that experienced rapid chloramine decay and nitrification while its absorbance signal at λ =254 nm decreased.A chloramine decay index（C.D.I） defined as the ratio of area beneath the HPSEC spectra at two different wavelengths of 230 and 254 nm,was used in assessing chloramine decay *** *** of waters at locations that experienced nitrification were consistently higher than locations not experiencing nitrification.A simulated laboratory study showed that the formation of nitrite/nitrate and/or soluble microbial products and/or the release of extracellular polymeric substances（EPS） during nitrification may contribute to the *** findings suggest that C.D.I derived from HPSEC with multiple wavelength UV detection could be an informative index to track the occurrence of rapid chloramine decay and nitrification.

关键词： HPSEC Water distribution systems Nitrification Chloramine decay

Transport receptor occupancy in nuclear pore complex mimics

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Nano Research 2022年第11期15卷 9689-9703页

作者： Alessio Fragasso Hendrik W.de Vries john Andersson Eli Ovan der Sluis Erik van der Giessen Patrick R.Onck Cees Dekker Department of Bionanoscience Kavli Institute of NanoscienceDelft University of TechnologyVan der Maasweg 9Delft 2629 HZThe Netherlands Zernike Institute for Advanced Materials University of GroningenNijenborgh 4Groningen 9747AGThe Netherlands Department of Chemistry and Chemical Engineering Chalmers University of TechnologyKemivägen 10Gothenburg SE-41296Sweden

Nuclear pore complexes(NPCs)regulate all molecular transport between the nucleus and the cytoplasm in eukaryotic *** disordered Phe-Gly nucleoporins(FG-Nups)line the central conduit of NPCs to impart a selective barrier where large proteins are excluded unless bound to a transport receptor(karyopherin;Kap).Here,we assess“Kap-centric”NPC models,which postulate that Kaps participate in establishing the selective *** combine biomimetic nanopores,formed by tethering Nsp1 to the inner wall of a solid-state nanopore,with coarse-grained modeling to show that yeast Kap95 exhibits two populations in Nsp1-coated pores:one population that is transported across the pore in milliseconds,and a second population that is stably assembled within the FG mesh of the *** current measurements show a conductance decrease for increasing Kap concentrations and noise data indicate an increase in rigidity of the *** reveals an accumulation of Kap95 near the pore wall,yielding a conductance *** find that Kaps only mildly affect the conformation of the Nsp1 mesh and that,even at high concentrations,Kaps only bind at most 8%of the FG-motifs in the nanopore,indicating that Kap95 occupancy is limited by steric constraints rather than by depletion of available *** data provide an alternative explanation of the origin of bimodal NPC binding of Kaps,where a stable population of Kaps binds avidly to the NPC periphery,while fast transport proceeds via a central FG-rich channel through lower affinity interactions between Kaps and the cohesive domains of Nsp1.

关键词： nuclear pore complex intrinsically disordered proteins nuclear transport receptors karyopherins nanopores biomimetics molecular dynamics coarse-grained modeling

The Global Standard Stratotype-section and Point （GSSP） for the base of the Eocene Series in the Dababiya section （Egypt）

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Episodes 2007年第4期30卷 271-286页

作者： Marie-Pierre Aubry Khaled Ouda Christian Dupuis William A., Berggren john A. van Couvering 无 Department of Earth and Planetary Sciences Rutgers University 610 Taylor Road Piscataway New Jersey 08554 USA8 Department of Geology University of Assiut Assiut Egypt Géologie Fondamentale et Appliquée Mons PolytechnicsRue de Houdain 9 B-7000 Mons Belgium The Micropaleontology Project 256 Fifth Avenue New York NY 10001 USA the Members of the Working Group on the Paleocene/Eocene Boundary

The GSSP for the base of the Eocene Series is located at 1.58 m above the base of Section DBH in the Dababiya Quarry, on the east bank of the Nile River, about 35 km south of Luxor, Egypt. It is the base of Bed 1 of the Dababyia Quarry Beds of the El Mahmiya Member of the Esna Formation, interpreted as having recorded the basal inflection of the carbon isotope excursion （CIE）, a prominent （3 to 5%） geochemical signature which is recorded in marine （deep and shallow） and terrestrial settings around the world. The Paleocene/Eocene boundary is thus truly a globally correlatable chronostratigraphic level.

关键词：层型断面始新世第三纪下层埃及

Nutritional and vitamin status in patients with neuroendocrine neoplasms

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World Journal of Gastroenterology 2019年第10期25卷 1171-1184页

作者： Dominique SVM Clement Margot ET Tesselaar Monique E van Leerdam Rajaventhan Srirajaskanthan john K Ramage Neuroendocrine Tumour Unit King’s College Hospital ENETS Centre of Excellence Department of Medical Oncology Netherlands Cancer Institute ENETS Centre of Excellence Department of Gastrointestinal Oncology Netherlands Cancer Institute Department of Gastroenterology King’s College Hospital

Symptoms of gastroenteropancreatic located neuroendocrine neoplasms(GEPNENs) are often related to food intake and manifest as abdominal pain or diarrhoea which can influence patients nutritional status. Malnutrition is common in cancer patients and influences quality of life, treatment options and survival but is also present in up to 40% of patients with GEP-NENs. As part of malnutrition there are often deficiencies in fat-soluble vitamins, mainly vitamin D. Little knowledge exists on trace elements. Several factors influence the development of malnutrition such as size and localisation of the primary tumour as well as metastases, side effects from treatment but also hormone production of the tumour itself. One of the main influencing factors leading to malnutrition is diarrhoea which leads to dehydration and electrolyte disturbances. Treatment of diarrhoea should be guided by its cause. Screening for malnutrition should be part of routine care in every GEP-NEN patient. Multidisciplinary treatment including dietician support is necessary for all malnourished patients with GEP-NENs.

关键词： Neuroendocrine neoplasm Nutrition Malnutrition Vitamin deficiency Diarrhoea Steatorrhoea

Acetylsalicylic acid supplementation improves protein utilization efficiency while vitamin E supplementation reduces markers of the inflammatory response in weaned pigs challenged with enterotoxigenic ***

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Journal of Animal Science and Biotechnology 2017年第1期8卷 143-153页

作者： Jae Cheol Kim Bruce P. Mullan john L. Black Robert J. E. Hewitt Robert J. van Barneveld john R. Pluske School of Veterinary and Life Sciences Murdoch University Murdoch WA 6150 Australia Department of Agriculture and Food Pork Innovation South Perth WA 6151 Australia john L Black Consulting Warrimoo NSW 2774 Australia SunPork Farms Solutions Loganholme QLD 4129 Australia Barneveld Nutrition Pry Ltd Loganholme QLD 4129 Australia

Background： This experiment was conducted to test the hypothesis that vitamin E（Vit E） and acetylsalicylic acid（ASA）, a cyclooxygenase-2（COX-2） inhibitor, will additively reduce the production of the immunosuppressive molecule prostaglandin E_2（PGE_2） and hence reduce inflammatory responses in weaner pigs experimentally infected with an enterotoxigenic strain of E. ***： The experiment was conducted in a research facility with 192 individually-housed male weaner pigs（Landrace × Large White） weighing 6.6 ± 0.04 kg（mean ± SEM）. The pigs were experimentally infected with an enterotoxigenic strain of E. coli and were allocated to a 2 × 3 factorial design with the respective factors being without and with 125 ppm ASA and three levels of Vit E supplementation（50, 100 or 200 IU/kg diet, dl-α-tocopheryl acetate）.Results： Acetylsalicylic acid supplementation improved average daily gain（P 〈 0.05） and tended to improve feed：gain ratio（P 〈 0.10） during the first 14 d after weaning. Acetylsalicylic acid supplementation also improved（P 〈 0.001） amino acid utilization efficiency（as assessed by plasma urea level） and tended to decrease（P 〈 0.10） PGE2 production in the liver without affecting smal intestinal histology and tight junction protein mR NA expression in the jejunal epithelium. Vitamin E supplementation greater than 100 IU/kg diet sustained both the plasma Vit E concentration（P 〈 0.001） and plasma haptoglobin content（P 〈 0.001） after weaning. However, there was no additive effects of the combined supplementation of ASA and Vit E on performance, intestinal barrier function and inflammatory responses of weaned ***： Although ASA and vitamin E improved amino acid utilization efficiency and reduced acute inflammatory responses, ASA and vitamin E did not additively reduce production of PGE2 and inflammatory responses in weaner pigs experimental y infected with an enterotoxigenic strain of E. coli.

关键词： Acetylsalicylic acid E.coli infection PGE_2 Vitamin E Weaner pigs

First-principles calculations of hyperfine interaction,binding energy,and quadrupole coupling for shallow donors in silicon

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npj Computational Materials 2020年第1期6卷 186-194页

作者： Michael W.Swift Hartwin Peelaers Sai Mu john J.L.Morton Chris G.van de Walle Department of Physics University of CaliforniaSanta BarbaraCA 93106-9530USA US Naval Research Laboratory Center for Computational Materials ScienceWashingtonDC 20375USA Materials Department University of CaliforniaSanta BarbaraCA 93106-5050USA Department of Physics and Astronomy University of KansasLawrenceKansas 66045USA Department of Electronic and Electrical Engineering UCLLondonWC1E 7JEUK

Spin qubits based on shallow donors in silicon are a promising quantum information technology with enormous potential scalability due to the existence of robust silicon-processing ***,the most accurate theories of donor electronic structure lack predictive power because of their reliance on empirical fitting parameters,while predictive ab initio methods have so far been lacking in accuracy due to size of the donor wavefunction compared to typical simulation *** show that density functional theory with hybrid and traditional functionals working in tandem can bridge this *** first-principles approach allows remarkable accuracy in binding energies(67 meV for bismuth and 54 meV for arsenic)without the use of empirical *** also obtain reasonable hyperfine parameters(1263 MHz for Bi and 133 MHz for As)and superhyperfine *** demonstrate the importance of a predictive model by showing that hydrostatic strain has much larger effect on the hyperfine structure than predicted by effective mass theory,and by elucidating the underlying mechanisms through symmetry analysis of the shallow donor charge density.

关键词： density donor hyperfine

Ephrin A2 receptor targeting does not increase adenoviral pancreatic cancer transduction in vivo

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World Journal of Gastroenterology 2009年第22期15卷 2754-2762页

作者： Michael A van Geer Conny T Bakker Naoya Koizumi Hiroyuki Mizuguchi john G Wesseling Ronald PJ Oude Elferink Piter J Bosma Liver Center of the Academic Medical Center of the University of Amsterdam Laboratory of Gene Transfer and Regulation National Institute of Biomedical Innovation

AIM:To generate an adenoviral vector specifically targeting the EphA2 receptor(EphA2R) highly expressed on pancreatic cancer cells in ***:YSA,a small peptide ligand that binds the EphA2R with high affinity,was inserted into the HI loop of the adenovirus serotype 5 fiber *** further increase the specificity of this vector,binding sites for native adenoviral receptors,the coxsackie and adenovirus receptor(CAR) and integrin,were ablated from the viral *** ablated retargeted adenoviral vector was produced on 293T *** c targeting of this novel adenoviral vector to pancreatic cancer was investigated on established human pancreatic cancer cell *** demonstrating specifi c in vitro targeting,in vivo targeting to subcutaneous growing human pancreatic cancer was tested by intravenous and intraperitoneal administration of the ablated adenoviral ***:Ablation of native cellular binding sites reduced adenoviral transduction at least *** of the YSA peptide in the HI loop restored adenoviral transduction of EphA2R-expressing cells but not of cells lacking this ***-mediated transduction was inhibited by addition of synthetic YSA *** transduction specificity of the ablated retargeted vector towards human pancreatic cancer cells was enhanced almost 10-fold in *** a subsequent in vivo study in a nude(nu/nu) mouse model however,no increased adenoviral targeting to subcutaneously growing human pancreas cancer nodules was seen upon injection into the tail vein,nor upon injection into the ***:Targeting the EphA2 receptor increases specificity of adenoviral transduction of human pancreatic cancer cells in vitro but fails to enhance pancreatic cancer transduction in vivo.

关键词： Pancreatic cancer Adenoviruses Ephrin A receptor Targeting Genetic transduction

一些含铀酰基团的次生铀矿物的生成自由能与稳定常数的预测

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地球与环境 1986年第3期 20-23页

作者： A.C.G.van genderen ,雨斌

前言在计算含铀矿物的溶液-矿物平衡时,由于得不到其稳定常数而进行了估算。Tardy 和 Garrels(1974,1976)已描述过常用的、预测氢氧化物和硅酸盐的生成自由能的方法。他们由构成矿物的金属氧化物和水合阳离子的自由能得出一个经验参数... 详细信息

前言在计算含铀矿物的溶液-矿物平衡时,由于得不到其稳定常数而进行了估算。Tardy 和 Garrels(1974,1976)已描述过常用的、预测氢氧化物和硅酸盐的生成自由能的方法。他们由构成矿物的金属氧化物和水合阳离子的自由能得出一个经验参数△O,这个参数与矿物的自由能有关。将这个方法稍加修改,使之适用于含铀矿物(磷酸盐、钒酸盐、砷酸盐和碳酸盐)的生成自由能的计算。作出

关键词：矿物金属金属材料铀矿稳定常数生成自由能碳化合物碳酸盐单斜磷酸盐矿物钙铀云母