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Geotechnical investigation of low-plasticity organic soil treated with nano-calcium carbonate

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第2期15卷 500-509页

作者： Govindarajan Kannan brendan c.O’Kelly Evangelin Ramani Sujatha centre for Advanced Research in Environment School of Civil EngineeringSASTRA Deemed to be UniversityThanjavurTamil Nadu613401India Department of civil Structural and Environmental EngineeringTrinity College DublinDublinD02 PN40Ireland

Soil stabilization using nanomaterials is an emerging research area although,to date,its investigation has mostly been laboratory-based and therefore requires extensive study for transfer to practical field *** present study advocates nano-calcium carbonate(Ncc)material,a relatively unexplored nanomaterial additive,for stabilization of low-plasticity fine-grained soil having moderate organic *** plasticity index,compaction,unconfined compressive strength(UcS),compressibility and permeability characteristics of the 0.2%,0.4%,0.6%and 0.8%Ncc-treated soil,and untreated soil(as control),were determined,including investigations of the effect of up to 90-d curing on the UcS and permeability *** terms of UcS improvement,0.4%Ncc addition was identified as the optimum dosage,mobilizing a UcS at 90-d curing of almost twice that for the untreated *** treated soil,particle aggregation arising from Ncc addition initially produced an increase in the permeability coef-ficient,but its magnitude decreased for increased curing owing to calcium silicate hydrate(cSH)gel formation,although still remaining higher compared to the untreated soil for all dosages and curing periods *** index decreased for all Ncc-treated soil *** micro-graphs indicated the presence of gel patches along with particle aggregation.X-ray diffraction(XRD)results showed the presence of hydration products,such as *** increases in UcS are initially attributed to void filling and then because of cSH gel formation with increased curing.

关键词： Organic silt calcium carbonate Nano-calcium carbonate(Ncc) calcium silicate hydrate(cSH) Soil stabilization

Intermittent swelling and shrinkage of a highly expansive soil treated with polyacrylamide

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 252-261页

作者： Amin Soltani An Deng Abbas Taheri brendan c.O’Kelly School of Engineering Information Technology and Physical SciencesFederation UniversityChurchillVIC3842Australia School of civil Environmental and Mining EngineeringThe University of AdelaideAdelaideSA5005Australia Department of civil Structural and Environmental EngineeringTrinity College DublinDublinD02 PN40Ireland

This laboratory study examines the potential use of an anionic polyacrylamide(PAM)-based material as an environmentally sustainable additive for the stabilization of an expansive soil from South *** experimental program consisted of consistency limits,sediment volume,compaction and oedometer cyclic swell-shrink tests,performed using distilled water and four different PAM-to-water solutions of P_(D)=0.1 g/L,0.2 g/L,0.4 g/L and 0.6 g/L as the mixing ***,the relative swelling and shrinkage strains were found to decrease with increasing number of applied swell-shrink cycles,with an‘elastic equilibrium’condition achieved on the conclusion of four *** propensity for swelling/shrinkage potential reduction(for any given cycle)was found to be in favor of increasing the PAM dosage up to P_(D)=0.2 g/L,beyond which the excess PAM molecules self-associate as aggregates,thereby functioning as a lubricant instead of a flocculant;this critical dosage was termed‘maximum flocculation dosage’(MFD).The MFD assertion was discussed and validated using the consistency limits and sediment volume properties,both exhibiting only marginal variations beyond the identified MFD of P_(D)=0.2 g/*** accumulated axial strain progressively transitioned from‘expansive’for the unamended soil to an ideal‘neutral’state at the MFD,while higher dosages demonstrated undesirable‘contractive’states.

关键词： Expansive soil Polyacrylamide(PAM) consistency limits Sediment volume Swell-shrink cycles Swelling and shrinkage strains Accumulated axial strain

Tumour induced osteomalacia due to a sinonasal hemangiopericytoma:A case report

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World Journal of clinical cases 2013年第1期1卷 59-63页

作者： Sophie A Jamal brendan c Dickson Ina Radziunas Division of Endocrinology Department of Medicine University of Toronto Toronto ON M5G 1N8 Canada Department of Pathology Mount Sinai Hospital Toronto ON M5G 1X5 Canada Multidisciplinary Osteoporosis Program Women’s College Hospital Toronto ON M5S 1B1 Canada

Tumour induced osteomalacia(TIO) is a rare and often unrecognized cause of hypophosphatemia. We report on a case of TIO due to a hemangiopericytoma originating from the left nasal sinus. The patient was a 55-year-old male with a 3-year history of left hip pain and an undisplaced left hip fracture. Biochemical testing demonstrated low levels of serum phosphate and serum 1,25-dihydroxyvitamin D, and an elevated level of fibroblast growth factor 23. Octreotide scanning demonstrated uptake in the left nasal sinus area and a computed tomography scan revealed a left nasal sinus mass. The patient underwent surgical resection of the mass and histology was consistent with a sinonasal hemangiopericytoma. His serum phosphate levels normalized almost immediately after surgery and he had complete resolution of hip pain. Our case highlights the importance of considering TIO when assessing patients with low serum phosphate.

关键词： Phosphate Osteomalacia Tumour Fibroblast growth factor 23

Nuclear Targeting of Methyl-Recycling Enzymes in Arabidopsis thaliana Is Mediated by Specific Protein Interactions

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Molecular Plant 2012年第1期5卷 231-248页

作者： Sanghyun Lee Andrew c. Doxey brendan J. Mcconkey Barbara A. Moffatt Department of Biology University of Waterloo Waterloo ON N2L 3G1 Canada Department of Developmental Biology Stanford University Stanford CA 94305 USA

Numerous transmethylation reactions are required for normal plant growth and development. S-adenosylhomocysteine hydrolase （SAHH） and adenosine kinase （ADK） act coordinately to recycle the by-product of these reactions, S-adenosylhomocysteine （SAH） that would otherwise competitively inhibit methyltransferase （MT） activities. Here, we report on investigations to understand how the SAH produced in the nucleus is metabolized by SAHH and ADK. Localization analyses using green fluorescent fusion proteins demonstrated that both enzymes are capable of localizing to the cytoplasm and the nucleus, although no obvious nuclear localization signal was found in their sequences. Deletion analysis revealed that a 41-amino-acid segment of SAHH （GlylS^-Lys19~） is required for nuclear targeting of this enzyme. This segment is surface exposed, shows unique sequence conservation patterns in plant SAHHs, and possesses additional features of protein-protein interaction motifs. ADK and SAHH interact in Arabidopsb via this segment and also interact with an mRNA cap MT. We propose that the targeting of this complex is directed by the nuclear localization signal of the MT; other MTs may similarly target SAHH/ADK to other subcellular compartments to ensure uninterrupted transmethylation.

关键词： Transmethylation subcellular localization S-adenosylhomocysteine hydrolase adenosine kinase nuclear targeting protein docking protein modeling protein motif analysis.

Same soup different taste-how to best manage the future liver remnant-a surgical perspective

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Hepatobiliary Surgery and Nutrition 2021年第5期10卷 734-736页

作者： John R.Bergquist Patrick Starlinger brendan c.Visser Division of Hepatobiliary and Pancreatic Surgery Department of SurgeryStanford UniversityStanfordCAUSA Division of Hepatobiliary and Pancreatic Surgery Department of SurgeryMayo ClinicRochesterMNUSA

A small but measurable percentage of major hepatic resection patients will experience major morbidity or mortality due post-hepatectomy liver failure after major liver ***-operative optimization,in particular pre-operative induction of liver growth to increase the future liver remnant(FLR)volume,has become frequently used in patients considered to be high ***,this process of hepatic augmentation remains incompletely understood,particularly in *** advances in techniques for FLR management have resulted in dramatic expansion of the liver surgeon’s armamentarium.

关键词： operative hepatic mortality

The influence of chemical composition on models of Type Ia supernovae

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Frontiers of physics 2013年第2期8卷 168-188页

作者： Alan c. calder brendan K. Krueger Aaron P. Jackson Dean M. Townsley Department of Physics Astronomy The State University of New York - Stony Brook Stony BrookUSA NY 11794 New York center for computational Sciences The State University of New York - Stony Brook Stony BrookUSA NY 11794 National Research council Research Associateship Program and Laboratories for computational Physics and Fluid Dynamics Naval Research Laboratory WashingtonUSA DC 20375 Department of Physics and Astronomy The University of Alabama TuscaloosaUSA AL 35487

Type Ia supernovae are bright stellar explosions distinguished by standardizable light curves that allow for their use as distance indicators for cosmological studies. Despite the highly successful use of these events in this capacity, many fundamental questions remain. contemporary research inves- tigates how properties of the progenitor system that follow from the host galaxy such as composition and age influence the brightness of an event with the goal of better understanding and assessing the intrinsic scatter in the brightness. We provide an overview of these supernovae and proposed progenitor systems, all of which involve one or more compact stars known as white dwarfs. We describe contemporary research investigating how the composition and structure of the progenitor white dwarf systematically influences the explosion outcome assuming the progenitor is a single white dwarf that has gained mass from a companion. We present results illustrating some of these systematic effects from our research.

关键词： hydrodynamics nuclear reactions nucleosynthesis abundances stars: supernovae:general stars: white dwarfs

Factors that mediate colonization of the human stomach by Helicobacter pylori

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World Journal of Gastroenterology 2014年第19期20卷 5610-5624页

作者： ciara Dunne brendan Dolan Marguerite clyne School of Medicine and Medical Science and conway Institute of Biomedical and Biomolecular Science University College DublinBelfieldDublin 4Ireland

Helicobacter pylori(***)colonizes the stomach of humans and causes chronic *** majority of bacteria live in the mucus layer overlying the gastric epithelial cells and only a small proportion of bacteria are found interacting with the epithelial *** bacteria living in the gastric mucus may act as a reservoir of infection for the underlying cells which is essential for the development of *** of gastric mucus is likely to be key to the establishment of chronic *** *** manages to colonise and survive in the hostile environment of the human stomach and avoid removal by mucus flow and killing by gastric acid is the subject of this *** also discuss how bacterial and host factors may together go some way to explaining the susceptibility to colonization and the outcome of infection in different *** infection of the gastric mucosa has become a paradigm for chronic *** of why *** is such a successful pathogen may help us understand how other bacterial species colonise mucosal surfaces and cause disease.

关键词： Helicobacter pylori colonization Infection Gastric mucosa Urease Flagella Polymorphisms Adhesins cagA Type IV secretion system

Origins of the supercontinent cycle

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Geoscience Frontiers 2013年第4期4卷 439-448页

作者： R.Damian Nance J.brendan Murphy Department of Geological Sciences.316 Clippinger Laboratories.Ohio University.Athens.OH 45701.USA Department of Earth Sciences st.Francis Xavier UniversityAntigonishNova Scotia B2G 2W5.Canada

The supercontinent cycle, by which Earth history is seen as having been punctuated by the episodic assembly and breakup of supercontinents, has influenced the rock record more than any other geologic phenomena, and its recognition is arguably the most important advance in Earth Science since plate tectonics. It documents fundamental aspects of the planet＇s interior dynamics and has charted the course of Earth＇s tectonic, climatic and biogeochemical evolution for billions of years. But while the widespread realization of the importance of supercontinents in Earth history is a relatively recent development, the supercontinent cycle was first proposed thirty years ago and episodicity in tectonic processes was recognized long before plate tectonics provided a potential explanation for its occurrence. With interest in the supercontinent cycle gaining momentum and the literature expanding rapidly, it is instructive to recall the historical context from which the concept developed. Here we examine the supercontinent cycle from this perspective by tracing its development from the early recognition of long-term epi- sodicity in tectonic processes, through the identification of tectonic cycles following the advent of plate tectonics, to the first realization that these phenomena were the manifestation of episodic superconti- nent assembly and breakup.

关键词： Supercontinent cyclePlate tectonicsTectonic episodicitySecular trends

Intruder familiarity and not duet similarity influences the territory defense in a year-round territorial bird species

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Avian Research 2022年第2期13卷 152-158页

作者： Tihana Hamzaj brendan Graham Katherine Bonilla Ignacio Gutiérrez Luis Sandoval Institute of Evolutionary Ecology and conservation Genomics University of UlmUlm Gemany Laboratorio de Ecología Urbana y comunicación Animal Escuela de BiologíaUniversidad de Costa RicaMontes de Oca CP11501-2060 Costa Rica Department of Biological Sciences University of Lethbridge4401 University Dr WLethbridgeABTIK 3M4anada

To avoid unnecessary energy expenditures in territorial defense,many species(e.g.,insects,amphibians,birds,and mammals)have developed the capability to distinguish between different intruder types using visual,acoustic,and/or chemical *** the mechanism used for intruder recognition is key to understanding the dynamics of territorial *** birds that use vocalizations for territorial defense,the frequency and duration of vocalizations or the familiarity with the intruder may be the main mechanism used for intruder ***,we conducted a playback experiment with territorial White-eared Ground-sparrows(Melozone leucotis),to analyze if territorial pairs recognize intruders using frequency and duration characteristics(a bird’s response is based on how structurally similar the intruders’duets are to their own)or by familiarity with the intruders(neighbors ***-neighbors).We focused on duets because this species uses duets exclusively for territorial *** broadcasted a duet from a territorial neighbor,two duets from non-neighbors(with different frequency and duration characteristics),and a duet from a control species in 39 territorial pair from three *** playback we measured five behavioral responses:latency of the first vocalization,latency of the approach to the speaker,time spent close the speaker(within 5 m),number of individuals that approached the speaker,and the number of *** found that territorial White-eared Ground-sparrow pairs responded stronger to neighbors than non-neighbors,and this response is not influenced by duet duration or frequency *** result suggests that neighbors represent a greater territorial threat for White-eared Ground-sparrows than *** work is necessary to understand how common this observation is for tropical species that defend small territories year-round.

关键词： Dear enemy Duets Neighbor-stranger discrimination Territory defense White-eared ground-sparrows