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Journal of Hydrodynamics 2013年第2期25卷 288-293页

作者： HORPPILA Jukka KAITARANTA Joni JOENSUU laura NURmINEN Leena Department of Environmental Sciences University of Helsinki

The effects of the emergent macrophyte Phragmites australis on water turbulence, bottom shear velocity and water turbidity were experimentally studied with the stem densities 0 stems/m2-100 stems/m2 and using organic-rich sediment. It is found that the maximum root-mean-square （rms） velocity and shear velocity decrease linearly with increasing stem density. By affecting the height of peak turbulence values, emergent plants can thus lower the frequency of sediment erosion events. Additionally, the slope of the rms turbulence increment decreases with increasing stem density. Thus, also the duration of strong turbulence is affected by the density of emergent macrophytes. The critical shear velocity for sediment resuspension is 0.0035 m/s-0.0055 rn/s and not affected by the stem density. In the absence of macrophytes, water flow causes a 6.3-fold increment in turbidity, but with macrophytes turbidity values remain lower. The experiments suggest that even relatively low densities of Phragmites can have substantial effects on water turbulence and consequently on water quality.

关键词： emergent macrophytes turbulence shear velocity resuspension turbidity

Self-centering steel plate shear walls for improving seismic resilience

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Frontiers of Structural and Civil Engineering 2016年第3期10卷 283-290页

作者： Patricia m. CLAYTON Daniel m. DOWDEN Chao-Hsien LI Jeffrey W. BERmAN michel BRUNEAU laura N. LOWES Keh-Chuan TSAI Department of Civil Architectural and Environmental Engineering University of Texas at Austin Austin TX 78705 USA Department of Civil Structural and Environmental Engineering University at Buffalo New York 14260-1660 USA National Center for Research on Earthquake Engineering Taipei Taiwan China Department of Civil and Environmental Engineering University of Washington Seattle WA 98195-2700 USA Department of Civil Structural and Environmental Engineering Taiwan University Taipei Taiwan China

As part of a Network for Earthquake Engineering Simulation research project led by researchers at the University of Washington with collaborators at University at Buffalo, and Taiwan National Center for Research on Earthquake Engineering, a self-centering steel plate shear wall （SC-SPSW） system has been developed to achieve enhanced seismic performance objectives, including recentering. The SC-SPSW consists of thin steel infill panels, referred to as web plates that serve as the primary lateral load-resisting and energy dissipating element of the system. Post- tensioned （PT） beam-to-column connections provide system recentering capabilities. A performance-based design procedure has been developed for the SC-SPSW, and a series of nonlinear response history analyses have been conducted to verify intended seismic performance at multiple hazard levels. Quasi-static subassembly tests, quasi-static and shake table tests of scaled three-story specimens, and pseudo-dynamic tests of two full-scale two-story SC-SPSWs have been conducted. As a culmination of this multi-year, multi-institutional project, this paper will present an overview of the SC- SPSW numerical and experimental research programs. This paper will also discuss innovative PT connection and web plate designs that were investigated to improve constructability, resilience, and seismic performance and that can be applied to other self-centering and steel plate shear wall systems.

关键词： self-centering steel plate shear walls large-scale experiment post-tensioned connections performance-baseddesign

Diarrhoea-predominant irritable bowel syndrome distinguishable by 16S rRNA gene phylotype quantification

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World Journal of Gastroenterology 2009年第47期15卷 5936-5945页

作者： Anna Lyra Teemu Rinttil Janne Nikkil Lotta Krogius-Kurikka Kajsa Kajander Erja malinen Jaana mtt laura mkel Airi Palva Department of Basic Veterinary Sciences Faculty of Veterinary Medicine University of HelsinkiHelsinki 00014Finland Alimetrics Ltd. EspooEspoo 02920Finland Valio Ltd. Research CentreHelsinki 00370 Finland Institute of Biomedicine Faculty of Medicine University of HelsinkiHelsinki 00014Finland VTT Biotechnology VTTEspoo 02044Finland The Finnish Red Cross Blood ServiceHelsinki 00310Finland Institute of Clinical medicine University of HelsinkiHelsinki 00014Finland

AIm:To study whether selected bacterial 16S ribosomal RNA(rRNA)gene phylotypes are capable of disting- uishing irritable bowel syndrome(IBS). mETHODS:The faecal microbiota of twenty volunteers with IBS,subdivided into eight diarrhoea-predominant (IBS-D),eight constipation-predominant(IBS-C)and four mixed symptom-subtype(IBS-m)IBS patients,and fifteen control subjects,were analysed at three time-points with a set of fourteen quantitative real-timepolymerase chain reaction *** assays targeted 16S rRNA gene phylotypes putatively associated with IBS,based on 16S rRNA gene library sequence analysis. The target phylotypes were affiliated with Actinobac-teria,Bacteroidetes and *** of the target phylotypes had less than 95%similarity to cultured bacterial species according to their 16S rRNA gene *** data analyses were made with repeated-measures ANCOVA-type modelling of the data and principle component analysis(PCA)with linear mixed-effects models applied to the principal component scores. RESULTS:Bacterial phylotypes Clostridium cocleatum 88%,Clostridium thermosuccinogenes 85%,Coprobacillus catenaformis 91%,Ruminococcus bromii-like, Ruminococcus torques 91%,and *** 93%were detected from all samples analysed.A multivariate analysis of the relative quantities of all 14 bacterial 16S rRNA gene phylotypes suggested that the intestinal microbiota of the IBS-D patients differed from other sample *** PCA on the first principal component(PC1),explaining 30.36%of the observed variation in the IBS-D patient group,was significantly altered from all other sample groups(IBS-D vs control, P=0.01;IBS-D vs IBS-m,P=0.00;IBS-D vs IBS-C, P=0.05).Significant differences were also observed in the levels of distinct phylotypes using relative values in proportion to the total amount of bacteria.A phy- lotype with 85%similarity to *** was quantified in significantly different quantities among the IBS-D and control subjects(-4.08±0.90 vs -

关键词： Irritable bowel syndrome Diarrhoea-predominant irritable bowel syndrome Intestinal microbiota Quantitative real-time polymerase chain reaction 16S ribosomal RNA

Impact of bolus volume on small intestinal intra-luminal impedance in healthy subjects

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World Journal of Gastroenterology 2010年第17期16卷 2151-2157页

作者： Nam Q Nguyen laura K Bryant Carly m Burgstad Robert J Fraser Daniel Sifrim Richard H Holloway Department of Gastroenterology & Hepatology Royal Adelaide HospitalAdelaide 5000Australia Investigation and Procedures Unit Repatriation General HospitalDaw Park 5041Australia Department of medicine Centre for Gastroen-terological ResearchK.U.LeuvenLeuven 3000Belgium

AIm: To assess the impact of bolus volume on the characteristics of small intestinal (SI) impedance ***: Concurrent SI manometry-impedance measurements were performed on 12 healthy volunteers to assess the pattern of proximal jejunal fluid bolus movement over a 14 *** subject was given 34 boluses of normal saline (volume from 1 to 30 mL) via the feeding tube placed immediately above the proximal margin of the studied segment.A bolus-induced impedance event occurred if there was > 12% impedance drop from baseline,over ≥ 3 consecutive segments within 10 s of bolus injection.A minor or major imped-ance event was defined as a duration of impedance drop minimum volume required for a detectable SI impedance event was 2 mL.A direct linear relationship between the SI bolus volume and the occurrence of impedance events was noted until SI bolus volume reached 10 mL,a volume which always produced an impedance flow *** was a moderate correlation between the bolus volume and the duration of impedance drop (r = 0.63,P mber of propagated channels (r = 0.50,P me boluses were associated with more major impedance events (≥ 10 mL boluses = 63%,3 mL boluses = 17%,and mL boluses = 0%,P = 0.02).CONCLUSION: Bolus volume had an impact on the type and length of propagation of SI impedance events and a threshold of 2 mL is required to produce an event.

关键词： Bolus volume Health Impedance Luminal flow Small intestine

Effects of perinatal protein deprivation and recovery on esophageal myenteric plexus

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World Journal of Gastroenterology 2010年第5期16卷 563-570页

作者： Flavio m Greggio Ricardo BV Fontes laura B maifrino Patricia Castelucci Romeu Rodrigues de Souza Edson A Liberti Autonomic Nervous System Laboratory (VQm) Department of Anatomy Instituto de Ciencias Biomedicas da Universidade de Sao Paulo 2415 Av Prof Lineu Prestes 05508-900 So Paulo Brazil

AIm:To evaluate effects of preand postnatal protein deprivation and postnatal recovery on the myenteric plexus of the rat esophagus. mETHODS: Three groups of young Wistar rats (aged 42 d) were studied: normalfed (N42), proteindeprived (D42), and proteinrecovered (R42). The myenteric neurons of their esophagi were evaluated by histochemical reactions for nicotinamide adenine dinucleotide (NADH), nitrergic neurons (NADPH)diaphorase and acetylcholinesterase (AChE), immunohistochemical reaction for vasoactive intestinal polypeptide (VIP), and ultrastructural analysis by transmission electron ***: The cytoplasms of large and medium neurons from the N42 and R42 groups were intensely reactive for NADH. Only a few large neurons from the D42 group exhibited this aspect. NADPH detected in the D42 group exhibited low reactivity. The AChE reactivity was diffuse in neurons from the D42 and R42 groups. The density of large and small varicosities detected by immunohistochemical staining of VIP was low in ganglia from the D42 group. In many neurons from the D42 group, the double membrane of the nuclear envelope and the perinuclear cisterna were not detectable. NADH and NADPH histochemistry revealed no group differences in the prof ile of nerve cell perikarya (ranging from 200 to 400 μm2).CONCLUSION: Protein deprivation causes a delay in neuronal maturation but postnatal recovery can almost completely restore the normal morphology of myenteric neurons.

关键词： Esophagus Enteric nervous system myenteric plexus Proteins Light microscopy Transmission electron microscopy

Anti-inflammatory potential of human corneal stroma-derived stem cells determined by a novel in vitro corneal epithelial injury model

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World Journal of Stem Cells 2019年第2期11卷 84-99页

作者： mariana Lizeth Orozco morales Nagi m marsit Owen D mcIntosh Andrew Hopkinson laura E Sidney Academic Ophthalmology Division of Clinical Neuroscience University of Nottingham

BACKGROUND An in vitro injury model mimicking a corneal surface injury was optimised using human corneal epithelial cells(hCEC).AIm To investigate whether corneal-stroma derived stem cells(CSSC) seeded on an amniotic membrane(Am) construct manifests an anti-inflammatory, healing *** Treatment of hCEC with ethanol and pro-inflammatory cytokines were compared in terms of viability loss, cytotoxicity, and pro-inflammatory cytokine release, in order to generate the in vitro injury. This resulted in an optimal injury of 20%(v/v) ethanol for 30 s with 1 ng/mL interleukin-1(IL-1) beta. Co-culture experiments were performed with CSSC alone and with CSSC-Am *** effect of injury and co-culture on viability, cytotoxicity, IL-6 and IL-8 production, and IL1 B, TNF, IL6, and CXCL8 mRNA expression were *** Co-culture with CSSC inhibited loss of hCEC viability caused by injury. Enzyme linked immunosorbent assay and polymerase chain reaction showed a significant reduction in the production of IL-6 and IL-8 pro-inflammatory cytokines, and reduction in pro-inflammatory cytokine mRNA expression during co-culture with CSSC alone and with the Am construct. These results confirmed the therapeutic potential of the CSSC and the possible use of Am as a cell carrier for application to the ocular *** CSSC were shown to have a potentially therapeutic anti-inflammatory effectwhen treating injured hCEC, demonstrating an important role in corneal regeneration and wound healing, leading to an improved knowledge of their potential use for research and therapeutic purposes.

关键词： Cornea Corneal injuries Injury model Corneal epithelium Corneal stroma-derived stem cells Amnion Anti-inflammatory Cell therapy

magmatism and metamorphism at ca. 1.45 Ga in the northern Gawler Craton: The Australian record of rifting within Nuna(Columbia)

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Geoscience Frontiers 2019年第1期10卷 175-194页

作者： laura J.morrissey Karin m.Barovich martin Hand Katherine E.Howard Justin L.Payne School of Natural and Built Environments University of South Australia Department of Earth Sciences School of Physical Sciences University of Adelaide

U-Pb monazite and zircon geochronology and calculated metamorphic phase diagrams from drill holes in the northern Gawler Craton, southern Australia, reveal the presence of ca. 1.45 Ga magmatism and metamorphism. magmatism and granulite facies metamorphism of this age has not previously been recognised in the Gawler Craton. The magmatic rocks have steep LREE-enriched patterns and high Ga/Al values, suggesting they are A-type granites. Calculated metamorphic forward models suggest that this event was associated with high apparent thermal gradients and reached pressures of 3.2 -5.4 kbar and temperatures of 775-815℃. The high apparent thermal gradients may reflect pluton-enhanced metamorphism, consistent with the presence of A-type granites. The recognition of ca. 1.45 Ga tectonism in the northern Gawler Craton is added to a compilation of ca. 1.50 -1.40 Ga magmatism, shear zone reactivation, rift basin development and isotope resetting throughout the South and North Australian Cratons that shows that this event was widespread in eastern Proterozoic Australia. This event is stylistically similar to ca. 1.45 Ga A-type magmatism and high thermal gradient metamorphism in Laurentia in this interval and provides further support for a connection between Australia and Laurentia during the mesoproterozoic. The tectonic setting of the 1.50-1.40 Ga event is unclear but may record rifting within the Nuna(or Columbia) supercontinent, or a period of intracontinental extension within a long-lived convergent setting.

关键词： Gawler Craton Laurentia metamorphism U-Pb geochronology Paleogeographic reconstruction

Identification of quantitative trait loci and associated candidate genes for pregnancy success in Angus–Brahman crossbred heifers

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The role of p53 in developmental syndromes

畜牧与生物技术杂志(英文版) 2024年第1期

作者： Quinn A.Hoorn Gabriel A.Zayas Eduardo E.Rodriguez laura m.Jensen Raluca G.mateescu Peter J.Hansen

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Journal of molecular Cell Biology 2019年第3期11卷 200-211页

作者： margot E.Bowen laura D.Attardi Division of Radiation and Cancer Biology in the Department of Radiation Oncology Stanford University School of MedicineStanfordCA 94305USA Department of Genetics Stanford University School of MedicineStanfordCA 94305USA

While it is well appreciated that loss of the p53 tumor suppressor protein promotes cancer,growing evidence indicates that increased p53 activity underlies the developmental defects in a wide range of genetic *** inherited or de novo mutations that cause these syndromes affect diverse cellular processes,such as ribosome biogenesis,DNA repair,and centriole duplication,and analysis of human patient samples and mouse models demonstrates that disrupting these cellular processes can activate the p53 ***,many of the developmental defects in mouse models of these syndromes can be rescued by loss of p53,indicating that inappropriate p53 activation directly contributes to their pathogenesis.A role for p53 in driving developmental defects is further supported by the observation that mouse strains with broad p53 hyperactivation,due to mutations affecting p53 pathway components,display a host of tissue-specific developmental defects,including hematopoietic,neuronal,craniofacial,cardiovascular,and pigmentation ***,germline activating mutations in TP53 were recently identified in two human patients exhibiting bone marrow failure and other developmental *** in mice suggest that p53 drives developmental defects by inducing apoptosis,restraining proliferation,or modulating other developmental programs in a cell type-dependent ***,we review the growing body of evidence from mouse models that implicates p53 as a driver of tissue-specific developmental defects in diverse genetic syndromes.

关键词： p53 mdm2 development embryo congenital defect syndrome genetic disorder

Second-Order Invariant Domain Preserving ALE Approximation of Euler Equations

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Communications on Applied mathematics and Computation 2023年第2期5卷 923-945页

作者： Jean-Luc Guermond Bojan Popov laura Saavedra Department of mathematics Texas A&M UniversityCollege StationUSA Departamento de matemática Aplicada a la Ingeniería Aeroespacial Universidad Politécnica de MadridMadridSpain

An invariant domain preserving arbitrary Lagrangian-Eulerian method for solving non-linear hyperbolic systems is *** numerical scheme is explicit in time and the approximation in space is done with continuous finite *** method is made invar-iant domain preserving for the Euler equations using convex limiting and is tested on vari-ous benchmarks.

关键词： Conservation equations Hyperbolic systems Arbitrary Lagrangian-Eulerian moving meshes Invariant domains High-order method Convex limiting Finite element method