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Design of soft magnetic materials

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npj Computational Materials 2022年第1期8卷 17-26页

作者： Ananya Renuka Balakrishna richard D.James Aerospace and Mechanical Engineering University of Southern CaliforniaLos AngelesCA90089USA Aerospace and Engineering Mechanics University of MinnesotaMinneapolisMN55455USA

We present a strategy for the design of ferromagnetic materials with exceptionally low magnetic hysteresis,quantified by *** this strategy,we use a micromagnetic algorithm that we have developed in previous research and which has been validated by its success in solving the“Permalloy Problem”—the well-known difficulty of predicting the composition 78.5%Ni of the lowest coercivity in the Fe–Ni system—and by the insight it provides into the“Coercivity Paradox”of ***,the design strategy predicts that cubic materials with large saturation magnetization ms and large magnetocrystalline anisotropy constant κ_(1) will have low coercivity on the order of that of Permalloy,as long as the magnetostriction constantsλ_(100),λ_(111)are tuned to special *** explicit prediction for a cubic material with low coercivity is the dimensionless number(c_(11)−c_(12))λ_(100)^(2)/(2_(κ_(1)))=81 for〈100〉easy *** results would seem to have broad potential application,especially to magnetic materials of interest in energy research.

关键词： magnetic cubic exceptional

Mafic-Ultramafic Large Igneous Provinces （LIPs）： Importance of the Pre-Mesozolc record

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Episodes 2007年第2期30卷 108-114页

作者： richard E. Ernst Ernst Geosciences 43 Margrave Ave Ottawa Ontario K 1T 3Y2 Canada. ＆ Adjunct professor Dept of Earth Sciences Carleton University Ottawa Canada K 1S 5B6.

Mafic-ultramafic magmatic provinces are termed Large Igneous Provinces （LIPs） if they are large （〉10^5 km^3）, are emplaced in a short duration （ca. 〈 5 myr）（or consist of short duration pulses）, and have intraplate characteristics （i.e. are not associated with normal plate boundary processes）. This category includes the classic continental flood basalts, oceanic plateaus, bimodal-rift （passive margin） related packages, but also those events, mainly of Phanerozoic-Proterozoic age, where the plumbing system of dykes, sills and layered intrusions has been exposed by erosion. In the Archean, LIPs may be represented by the greenstone belts of the tholeiite-komatiite association. Felsic magmatism is associated with many LIPs and indeed may be dominant in some cases. LIPs are associated with continental breakup, climatic change, extinction events, and major ore deposits especially of the Ni-Cu-PGE type. Continental LIPs occur on average every 20-30 myr since 2.6 Ga; the Archean record is too poorly preserved for generalizations. LIPs occur both as isolated single events （e.g., 2055 Ma Bushveld event）, as approximately coeval but widely separated events （e.g., 65 Ma Deccan and 62 Ma NAIP）, and as regional clusters associated with supercontinent breakup （e.g., the 830-750 Ma events associated with the breakup of the proposed supercontinent Rodinia）. The LIP record represents a key tool for constraining Proterozoic paleocontinental reconstructions.

关键词：铁镁质火成地区超基性重要记录

Therapeutic endoscopy for the treatment of post-bariatric surgery complications

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World Journal of Gastroenterology 2022年第2期28卷 199-215页

作者： Michael Larsen richard Kozarek Digestive Disease Institute Virginia Mason Medical CenterSeattleWA 98101United States

Obesity rates continue to climb *** often contributes to other comorbidities such as type 2 diabetes,hypertension,heart disease and is a known risk factor for many *** surgeries are by far the most invasive treatment options available but are often the most effective and can result in profound,durable weight loss with improvement in or resolution of weight associated *** performed bariatric surgeries include Rouxen-Y gastric bypass,sleeve gastrectomy,and laparoscopic gastric *** surgeries are associated with significant weight loss,but also with significant rates of major *** complexity of these patients and surgical anatomies makes management of these complications by a multidisciplinary team critical for optimal *** invasive treatments for complications are typically preferred because of the high risk associated with repeat *** plays a large role in both the diagnosis and the management of *** can provide therapeutic interventions for many bariatric surgical complications including anastomotic strictures,anastomotic leaks,choledocholithiasis,sleeve stenosis,weight regain,and eroded *** should be familiar with the various surgical anatomies as well as the various therapeutic options *** review article serves to delineate the current role of endoscopy in the management of complications after bariatric surgery.

关键词： Therapeutic endoscopy Bariatric surgery Complications Weight regain Sleeve stenosis Sleeve leak

Ecology and Behaviour of Burton's Legless Lizard(Lialis burtonis,Pygopodidae) in Tropical Australia

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Asian Herpetological Research 2013年第1期4卷 9-21页

作者： Michael WALL richard SHINE School of Biological Sciences A08 University of Sydney

The elongate, functionally limbless flap-footed lizards （family Pygopodidae） are found throughout Australia, ranging into southern New Guinea. Despite their diversity and abundance in most Australian ecosystems, pygopodids have attracted little scientific study. An intensive ecological study of one pygopodid, Burton＇s legless lizard （Lialis burtonis Gray 1835）, was conducted in Australia＇s tropical Northern Territory. L. burtonis eats nothing but other lizards, primarily skinks, and appears to feed relatively infrequently （only 20.8% of stomachs contained prey）. Ovulation and mating occur chiefly in the late dry-season （beginning around September）, and most egg-laying takes place in the early to middle wet-season （November-January）. Females can lay multiple clutches per year, some of which may be fertilised with stored sperm. Free-ranging L. burtonis are sedentary ambush foragers, with radio-tracked lizards moving on average 〈 5 m/day. Most foraging is done diurnally, but lizards may be active at any time of day or night. Radiotracked lizards were usually found in leaf-litter microhabitats, a preference that was also evident in habitat-choice experiments using field enclosures. Lizards typically buried themselves in 6-8 cm of litter; at this depth, they detect potential prey items while staying hidden from predators and prey and avoiding lethally high temperatures.

关键词： Squamata habitat use wet-dry tropics thermoregulation movement activity patterns

Tissue Engineering to Restore Cardiac Function

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Engineering 2022年第6期8卷 13-17页

作者： richard D.Weisel Toronto General Research Institute Toronto General HospitalUniversity Health Network&Department of SurgeryDivision of Cardiac SurgeryUniversity of TorontoTorontoON M5G 2C4Canada

1. Introduction The purpose of cardiac surgery is to restore the injured heart to full function. For many congenital cardiac defects, appropriate repair is able to establish nearly normal cardiac function. One example of such repair is closing abnormal holes between cardiac chambers in young children, which usually restores normal function that persists for the lifetime of the child. However, the advent of surgery for ischemic heart disease has resulted in new challenges for cardiac surgeons.

关键词： function surgery lifetime

Gap formation around Ω_e/2 and generation of low-band whistler waves by Landau-resonant electrons in the magnetosphere: Predictions from dispersion theory

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Earth and Planetary Physics 2020年第2期4卷 138-150页

作者： Konrad Sauer Klaus Baumgartel richard Sydora Max-Planck-Institute for Solar System Research GöttingenGermany(up to 2005 Leibnitz-Institut für Astrophysik(AIP) PotsdamGermany(up to 2008 Institute for Geophysical Research University of AlbertaEdmontonCanada

In this paper we show that two significant phenomena of magnetospheric chorus emission can be explained by the participation of beam-like electron structures,created by Landau-resonant interaction with growing oblique whistler *** first concerns the widely observed spectral gap near half the electron cyclotron frequency Ωe;the second is related to the observation of very obliquely propagating lower-band waves that cannot be directly generated by temperature *** the gap,kinetic dispersion theory reveals that interference of the beam-related cyclotron mode ω~Ωe-kVb with the conventional whistler mode leads to mode splitting and the appearance of a ’forbidden’ area in the ω-k *** the beam velocity appears as an essential *** is directly related to the phase velocity of the most unstable whistler wave mode,which is close to VAe/2 for sufficiently hot electrons(VAe is the electron Alfven velocity).To clarify the second point,we show that Landau-resonant beams with Vb Vb

关键词： important role play Landau-resonant electrons modification of the electron distribution function gap formation at half the electron cyclotron frequency

MINNESOTA SUSTAINABLE BUILDING GUIDELINES:History,Effectiveness and Path for the Future.

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Journal of Green Building 2018年第2期13卷 163-180页

作者： richard Graves Patrick Smith Center for Sustainable Building Research College of DesignUniversity of Minnesota1425 University Avenue SESuite 115MinneapolisMN 55455

INTRODUCTION The Minnesota Sustainable Building Guidelines is a progressive sustainability program for state funded buildings which serves as a model for sustainability in Minnesota *** program was created by the State of Minnesota in 2001 and developed by a team led by the Center for Sustainable Building Research(CSBR)at the University of *** other green building programs,it focuses on measured performance improvements,using a list of required metrics instead of a menu of potential *** program is structured to provide a feedback loop to the building design,construction and operations industry in the *** of the program are used through all phases of the development of state-funded buildings in Minnesota from pre-design through design,and construction and for ten years of *** is continually updated and improved in collaboration with state agencies and industry stakeholders and could serve as a model for localized green building programs.

关键词： green building rating systems code climate change architecture 2030 emission reduction actual performance net zero EUI renewable

A study of process-induced grain structures during steady state and non-steady state electron-beam welding of a titanium alloy

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Journal of Materials Science & Technology 2022年第18期113卷 117-127页

作者： Yu Lu richard Turner Jeffery Brooks Hector Basoalto School of Metallurgy and Materials University of BirminghamBirminghamB152TTUnited Kingdom Department of Materials Science and Engineering The University of SheffieldMappin StreetSheffieldS13JDUnited Kingdom

A detailed microstructural characterisation of the emerging weld-line grain structure,for bead-upon-plate welds in Ti-6Al-4V(Ti64)of differing plate thickness,was *** microstructure studied was formed during both steady state and non-steady state sections within the weld path,with the non-steady state portion being taken from the end of the plate as the weld bead and heat source overhang the edge of the *** allows for the effects of welding process conditions on the microstructural evolution to be *** weld pool geometry and 3D tomography of the weld-induced defects have been *** characterisation of microstructure and texture for different welding parameters and for steady and non-steady states have been used to identify physical parameters for the microstructure predictions that are difficult to obtain *** different states significantly affect the weld crown shape and formation,weld toe,weld bead depth and ***,the heat affected zone(HAZ)re-mains *** the microstructural evolution,both the steady and non-steady states have similar microstructure and *** defects were observed in the steady state section of welds,but sub-surface spherical pores have been observed in the non-steady state section of a *** element modelling to simulate the thermal-metallurgical-mechanical fields within the steady and non-steady state sections of the welds was considered,and the cooling rates predicted within steady state and non-steady sections were interrogated to improve the theoretical understanding of the microstructure and defect formation differences in these Ti64 EB weld regions.

关键词： Electron-beam fusion welding Processing Microstructure Ti-6Al-4V

Does disruptive camouflage conceal edges and features？

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Current Zoology 2015年第4期61卷 708-717页

作者： richard J. WEBSTER Department of Biology Carleton University Ottawa K1S 5B6 Canada

Camouflage is ubiquitous in the natural world and benefits both predators and prey. Amongst the range of conceal- ment strategies, disruptive coloration is thought to visually fragment an animal＇s＇ outline, thereby reducing its rate of discovery. Here, I propose two non-mutually exclusive hypotheses for how disruptive camouflage functions, and describe the visual me- chanisms that might underlie them. （1） The local edge disruption hypothesis states that camouflage is achieved by breaking up edge information. （2） The global feature disruption hypothesis states camouflage is achieved by breaking up the characteristic features of an animal （e.g., overall shape or facial features）. Research clearly shows that putatively disruptive edge markings do increase concealment; however, few tests have been undertaken to determine whether this survival advantage is attributable to the distortion of features, so the global feature disruption hypothesis is under studied. In this review the evidence for global feature disruption is evaluated. Further, I address if object recognition processing provides a feasible mechanism for animals＇ features to influence concealment. This review concludes that additional studies are needed to test if disruptive camouflage operates through the global feature disruption and proposes future research directions [Current Zoology 61 （4）： 708-717, 2015].

关键词： Antipredator Background matching Contour Crypsis Camouflage Disruptive coloration Edge detection Objectrecognition