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Combined flow-focus and self-assembly routes for the formation of lipid stabilized oil-shelled microbubbles

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Microsystems & Nanoengineering 2018年第1期4卷 466-473页

作者： Adam H.Churchman Victoria Mico Julia Gala de Pablo sally A.Peyman s.even Freear stephen D.evans school of Physics and Astronomy University of LeedsWoodhouse LaneLeeds LS29JTUK school of Electronic and Electrical Engineering University of LeedsWoodhouse LaneLeeds LS29JTUK

Lipid and polymer stabilized microbubbles are used in medicine as contrast agents for ultrasound imaging and are being developed for the delivery of water soluble drugs to diseased areas of the ***,many new therapeutics exhibit poor water solubility or stability,which has led to the requirement for the development of effective hydrophobic drug delivery *** study presents a new method to produce microbubbles coated with an oil layer capable of encapsulating hydrophobic drugs and suitable for targeted,triggered drug *** new method utilizes highly controllable flow-focusing microfluidics with lipid oil nanodroplets self-assembling and spreading at gas–aqueous *** layer inside microbubbles were produced with diameters of 2.4±0.3μm(s.d.,1.6μm)and at concentrations up to 10^(6) bubbles per *** mechanism of oil layer inside microbubble assembly and stability were characterized using methods including contact angle measurements,quartz crystal microbalance with dissipation monitoring and fluorescence resonance energy transfer imaging.

关键词： microbubbles microfluidics drug-delivery hydrophobic lipid-coated oil-shelled

Feasibility of confocal endomicroscopy in the diagnosis of pediatric gastrointestinal disorders

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World Journal of Gastroenterology 2009年第18期15卷 2214-2219页

作者： Krishnappa Venkatesh Marta Cohen Clair evans Peter Delaney s.even Thomas Christopher Taylor Ashraf Abou-Taleb Ralf Kiesslich Mike Thomson Centre for Pediatric Gastroenterology Sheffield Children's NHS Foundation TrustSheffieldS10 2THUnited Kingdom Department of Histopathology Sheffield Children's NHS Foundation TrustSheffieldS10 2THUnited Kingdom Optiscan PO Box 1066Mt WaverleyMDCVictoriaAustralia 3149Australia I.Med.Klink und Poliklinik Johannes Gutenberg University of MainzMainz 55131Germany

AIM： To evaluate the feasibility and utility of confocal laser endomicroscopy （CLE） in the description of normal gastrointestinal （GI） mucosa and in the diagnosis of GI disorders in children, in comparison to ***： Forty-four patients （19 female） median age 10.9 years （range 0.7-16.6 years） with suspected or known GI pathology underwent esophago-gastro- duodenoscopy （OGD）（n = 36） and/or ileocolonoscopy （IC）（n = 31） with CLE using sodium fluorescein and acriflavine as contrast agents. Histological sections were compared with same site confocal images by two experienced pediatric and GI histopathologists and endoscopists, ***： Duodenum and ileum were intubated in all but one patient undergoing OGD and IC. The median procedure time was 16.4 min （range 7-25 rain） for OGD and 27.9 min （range 15-45 min） for IC. A total of 4798 confocal images were compared with 153 biopsies from the upper GI tract from 36 procedures, and 4661 confocal images were compared with 188 biopsies from the ileocolon from 31 *** images were comparable to conventional histology both in normal and in pathological conditions such as esophagitis, Helicobacter pylori gastritis, celiac disease, inflammatory bowel disease, colonic heterotopia, and graft versus host ***： CLE offers the prospect of targeting biopsies to abnormal mucosa, thereby increasing diagnostic yield, reducing the number of biopsies, decreasing the burden on the histopathological services, and reducing costs.

关键词： Confocal laser endomicroscopy Histology Pediatric Gastrointestinal mucosa Gastrointestinaldisorders

ADVANCED QUALITY CONCEPTs AND COMPOsITE RELIABILITY THROUGH sTATIsTICALPROCEss CONTROL

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Acta Metallurgica sinica(English Letters) 1997年第3期10卷 263-269页

作者： D. evans (CCLRC, Rutherford Appleton Laboratory, Chilton, Oxon. OX14 2HQ U.K.) Rutherford Appleton Lab Oxon United Kingdom

The physical properties of thermosetting resins and resin based composites may be influenced by changes in any one of the mang formulating or process related variables involved in their manufacture. When resins and composite materials are required to perform in aggressive environments, reliable and predicable performance is essential and therefore these materials must be prepared and tested in accorkance with a strictquality plan. This paper outlines the elements of statistical process control (s.P.C.)as it may be applied to non-metallic materials and discusses the concept of Capability Index (Cp).

关键词： physical property composite process control cryogenic application

The spatial and Temporal Characteristics of Rainfall over the Lake Victoria Basin of Kenya in 1987-2016

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Atmospheric and Climate sciences 2020年第2期10卷 240-257页

作者： Wabwire Odhiambo evans s. N. Mukhovi I. A. Nyandega Catholic University of Eastern Africa Nairobi Kenya University of Nairobi Kenya Nairobi Kenya

Climate extremes have increased in the recent past and they are further being exacerbated by climate change and variability. In this paper, we sought to determine rainfall characteristics over the Lake Victoria Basin of Kenya in 1987-2016, as a basis of understanding climate variability. The methodology used included;standardized Precipitation Index to depict variability, coefficient of variation for spatial analysis and the Mann-Kendall test to test the presence of trends in data. We established that Lake Victoria basin is relatively wet through-out the year, with two distinct rainfall seasons March-April-May (MAM) and October-November-December (OND) that support human livelihood and ecology. The normal wetness conditions have declined over time, paving way for both dry and wet extremes conditions between 1997-1998 and 2002-2006, respectively. The rainfall extremes have become frequent in the last decade in 2007-2016. We also established a decline in the MAM rainfall seasons, and an increase during the October-December rainfall seasons in 1987-2016. Furthermore, the number of rainy days has declined with the onset and cessations of both long rains and short rains having shown a variability of at least 50% and 30% respectively, in a range of about 100 to 200 Julian days. The decline in wet condition is likely to affect economic activities especially the rainfed agriculture. The changing rainfall trends over the basin therefore, call for proper human livelihood planning and ecological monitoring in order to achieve ecological sustainability.

关键词： Climate Variability seasonal Rainfall Intra-seasonal Rainfall Characteritics and Lake Victoria Basin

Granular titanite from the Roter Kamm crater in Namibia:Product of regional metamorphism,not meteorite impact

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Geoscience Frontiers 2022年第3期13卷 156-163页

作者： Aaron J.Cavosie Christopher J.spencer Noreen evans Kai Rankenburg Robert J.Thomas Paul H.Macey space science and Technology Centre and The Institute for Geoscience Research School of Earth and Planetary ScienceCurtin UniversityPerthWA 6102Australia Dept.of Geological sciences and Geological Engineering Queen’s UniversityOntarioCanada John de Laeter Centre Curtin UniversityPerthWA 6102Australia Council for Geoscience BellvilleWestern CapeSouth Africa

Accessory minerals with so-called granular texture have risen in importance as geochronological tools for U-Pb dating of meteorite impact events. Grain-scale recrystallization, typically triggered by a combination of high-strain deformation and post-impact heating, can create a polycrystalline microstructure consisting of neoblasts that expel radiogenic Pb, which are thus ideal for isotopic dating. While granular domains in zircon and monazite from shocked rocks have been demonstrated to preserve impact ages,few U-Pb dating studies have been conducted on granular microstructures in titanite(CaTisiO;). Here we report the occurrence of granular-textured titanite from ~2020 Ma granite basement rock exposed in the rim of the 4–5 Ma Roter Kamm impact structure in Namibia. Orientation mapping reveals two microstructurally distinct titanite populations: one consisting of strained/deformed grains, and the other consisting of grains that comprise aggregates of strain-free neoblasts. In situ U-Pb geochronology on 37 grains shows that most grains from both titanite populations yield indistinguishable U-Pb dates of ca.1025 Ma, consistent with the observed microstructures forming during the Mesoproterozoic Namaqua Orogeny. Only four grains preserved older age domains, recording ca. 1875 Ma Paleoproterozoic metamorphism. Two significant observations emerge:(1) none of the analyzed titanite grains yield the 2020 Ma igneous crystallization age previously established from zircon in the same sample, and(2) no age-resetting was detected that could be attributed to the 4 to 5 Ma Roter Kamm impact *** the similarity of the neoblastic microstructure to minerals from other sites with an established impact provenance, the granular texture and near-complete Pb-loss in titanite from Roter Kamm granite instead records a Paleo-to Mesoproterozoic polymetamorphic history, rather than Miocene age shockrelated processes. These results highlight the critical importance of grain-scale cont

关键词： Namibia Roter Kamm Titanite EBsD Geochronology

strategies towards robust interpretations of in situ zircon Lu-Hf isotope analyses

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Geoscience Frontiers 2020年第3期11卷 843-853页

作者： C.J.spencer C.L.Kirkland N.M.W.Roberts N.J.evans J.Liebmann school of Earth and Planetary sciences The Institute for Geoscience Research(TIGeR)Curtin UniversityPerthAustralia Department of Geological sciences and Geological Engineering Queen’s UniversityKingstonCanada Centre for Exploration Targeting-Curtin Node The Institute for Geoscience ResearchSchool of Earth and Planetary SciencesCurtin UniversityPerthAustrali Geochronology and Tracers Facility British Geological SurveyNottinghamUK John de Laeter Centre GeoHistory Facility School of Earth and Planetary SciencesCurtin UniversityPerthAustralia

The combination of U-Pb and Lu-Hf compositions measured in zircon crystals is a remarkably powerful isotopic couplet that provides measures on both the timing of mineral growth and the radiogenic enrichment of the source from which the zircon *** U-Pb age documents the timing of zircon crystallization/recrystallization and Hf isotopes inform on the degree to which the host melt was derived from a radiogenic reservoir(*** mantle) versus an unradiogenic reservoir(*** continental crust),or some mixture of these *** ease of generating large quantities of zircon U-Pb and Lu-Hf data has been in large part facilitated by instrument ***,the dramatic increase in time constrained zircon Lu-Hf analyses in the Earth science community has brought to the fore the importance of careful data collection and reduction workflows,onto which robust geological interpretations may be *** this work,we discuss the fundamentals of Lu-Hf isotopes in zircon,which then allows us to provide a robust,accessible,methodology for the assessment of data ***,we discuss some novel techniques for:data visualization—that facilitates better transparency of data interpretation;integration of geographic information—that may reveal spatial trends where temporal trends were only apparent before;and some novel statistical evaluation tools—that may provide more rigorous interand intra-sample comparisons.

关键词： Zircon Geochronology Isotope geochemistry Lu-Hf isotopes Geostatistics Data visualization

Preoperative selection of patients with colorectal cancerliver metastasis for hepatic resection

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World Journal of Gastroenterology 2016年第2期22卷 567-581页

作者： Rafif E Mattar Faisal A Al-alem eve simoneau Mazen Hassanain Department of surgery College of MedicineKing Saud UniversityRiyadh 11461Saudi Arabia Department of surgery McGill University Health CentreHepatopancreaticobiliary Research UnitMontrealQC H4A 3J1Canada Department of Oncology McGill University Health CenterMontrealQC H4A 3J1Canada

surgical resection of colorectal liver metastases(CRLM) has a well-documented improvement in survival. To benefit from this intervention, proper selection of patients who would be adequate surgical candidates becomes vital. A combination of imaging techniques may be utilized in the detection of the lesions. The criteria for resection are continuously evolving; currently, the requirements that need be met to undergo resection of CRLM are: the anticipation of attaining a negative margin(R0 resection), whilst maintaining an adequate functioning future liver remnant. The timing of hepatectomy in regards to resection of the primary remains controversial; before, after, or simultaneously. This depends mainly on the tumor burden and symptoms from the primary tumor. The role of chemotherapy differs according to the resectability of the liver lesion(s); no evidence of improved survival was shown in patients with resectable disease who received preoperative chemotherapy. Presence of extrahepatic disease in itself is no longer considered a reason to preclude patients from resection of their CRLM, providing limited extra-hepatic disease, although this currently is an area of active investigations. In conclusion, we review the indications, the adequate selection of patients and perioperative factors to be considered for resection of colorectal liver metastasis.

关键词： Colorectal cancer liver metastases Liverresection Hepatectomy Patient selection Preoperativeselection

Prenatal Testing or screening?

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Maternal-Fetal Medicine 2020年第4期2卷 217-222页

作者： evans Mark I. evans shara M. Fetal Medicine Foundation of America New YorkNY 10065USA Comprehensive Genetics New YorkNY 10065USA Department of Obstetrics&Gynecology Icahn School of Medicine at Mt.SinaiNew YorkNY 10029USA Department of Maternal Child Health Gillings School of Public Health University of North Carolina at Chapel HillChapel HillNY 27599USA

Over the past 50 years,the scope and extent of prenatal diagnosis and screening for genetic disorders have improved *** has been a pendulum like swing from testing to screening back and forth as new technologies *** concurrent developments of cell free fetal DNA analysis of maternal blood has dramatically changed patient’s choices towards ***,with the use of array comparative genomic hybridization of fetal DNA that requires diagnostic procedures(Chorionic villus sampling and amniocentesis),much more extensive diagnosis can be *** noninvasive methods can replicate what can be done with diagnostic procedures there still will be a"price to be paid"for opting for the non-invasive methods.

关键词： Genetic counseling Prenatal diagnosis Chorionic villus sampling Amniocentesis Array comparative genomic hybridization Noninvasive prenatal testing

Disruptions in AUXl-Dependent Auxin Influx Alter Hypocotyl Phototropism in Arabidopsis

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Molecular Plant 2008年第1期1卷 129-144页

作者： Bethany B. stonea Emily L. stowe-evans Reneé M. Harper R. Brandon Celaya Karin Ljung Goran sandbergc Emmanuel Liscum Division of Biological sciences University of Missouri Columbia Missouri 65211 USA Christopher s. Bond Life sciences Center University of Missouri Columbia Missouri 65211 USA Department of Forest Genetics and Plant Physiology Umea Plant Science Center SE-90183 Umea Sweden Current address: Biology Department Bucknell University Lewisburg Pennsylvania 17837 USA.

Phototropism represents a differential growth response by which plant organs can respond adaptively to changes in the direction of incident light to optimize leaf/stem positioning for photosynthetic light capture and root growth orientation for water/nutrient acquisition. studies over the past few years have identified a number of compo- nents in the signaling pathway（s） leading to development of phototropic curvatures in hypocotyls. These include the pho- totropin photoreceptors （photl and phot2） that perceive directional blue-light （BL） cues and then stimulate signaling, leading to relocalization of the plant hormone auxin, as well as the auxin response factor NPH4/ARF7 that responds to changes in local auxin concentrations to directly mediate expression of genes likely encoding proteins necessary for development of phototropic curvatures, While null mutations in NPH4/ARF7 condition an aphototropic response to unidirectional BL, seedlings carrying the same mutations recover BL-dependent phototropic responsiveness if coirradiated with red light （RL） or pre-treated with either ethylene. In the present study, we identify second-site enhancer mutations in the nph4 background that abrogate these recovery responses. One of these mutations-mapl （modifier of arf7 phenotypes 1）-was found to represent a missense allele of AUX1-a gene encoding a high-affinity auxin influx carrier previously associated with a number of root responses. Pharmocological studies and analyses of additional auxl mutants confirmed that AUX1 functions as a modulator of hypocotyl phototropism. Moreover, we have found that the strength of dependence of hypocotyl phototropism on AUX1-mediated auxin influx is directly related to the auxin responsiveness of the seedling in question.

关键词： AUX1-Dependent Auxin NPH4/ARF7