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magnetic Helical micro-and Nanorobots:Toward Their Biomedical Applications

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Engineering 2015年第1期1卷 21-26页

作者： Famin Qiu bradley j.Nelson Institute of Robotics and Intelligent Systems(IRIS) ETH Zurich

magnetic helical micro- and nanorobots can perform 3D navigation in various liquids with a sub- micrometer precision under low-strength rotating magnetic fields （〈 10 rer）. Since magnetic fields with low strengths are harmless to cells and tissues, magnetic helical micro/ nanorobots are promising tools for biomedical applications, such as minimally invasive surgery, cell manipulation and analysis, and targeted therapy. This review provides general information on magnetic helical micro/nanorobots, including their fabrication, motion control, and further functionalization for biomedical applications.

关键词： magnetic helical micro/nanorobots mobilemicro/nanorobots artificial bacterial flagella (ABFs) functionalization biomedical applications

Force microscopy of the Caenorhabditis elegans embryonic eggshell

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microsystems & Nanoengineering 2020年第1期6卷 1029-1039页

作者： Roger Krenger jan T.Burri Thomas Lehnert bradley j.Nelson martin A.m.Gijs Laboratory of microsystems Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland multi-Scale Robotics Laboratory ETH ZurichZürich 8092Switzerland

Assays focusing on emerging biological phenomena in an animal’s life can be performed during *** the embryo of Caenorhabditis elegans has been extensively studied,its biomechanical properties are largely ***,we demonstrate that cellular force microscopy(CFm),a recently developed technique that combines micro-indentation with high resolution force sensing approaching that of atomic force microscopy,can be successfully applied to *** *** performed,for the first time,a quantitative study of the mechanical properties of the eggshell of living *** embryos and demonstrate the capability of the system to detect alterations of its mechanical parameters and shell defects upon chemical *** addition to investigating natural eggshells,we applied different eggshell treatments,i.e.,exposure to sodium hypochlorite and chitinase solutions,respectively,that selectively modified the multilayer eggshell structure,in order to evaluate the impact of the different layers on the mechanical integrity of the *** element method simulations based on a simple embryo model were used to extract characteristic eggshell parameters from the experimental micro-indentation force-displacement *** found a strong correlation between the severity of the chemical treatment and the rigidity of the ***,our results showed,in contrast to previous assumptions,that short bleach treatments not only selectively remove the outermost vitelline layer of the eggshell,but also significantly degenerate the underlying chitin layer,which is primarily responsible for the mechanical stability of the egg.

关键词： remove rigidity approaching

Arabidopsis FtsZ2-1 and FtsZ2-2 Are Functionally Redundant, But FtsZ-Based Plastid Division Is Not Essential for Chloroplast Partitioning or Plant Growth and Development

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molecular Plant 2009年第6期2卷 1211-1222页

作者： Aaron j. Schmitz jonathan m. Glynn bradley j.S.C. Olson Kevin D. Stokes Katherine W. Osteryoung Department of Plant Biology 166 Plant Biology Bldg Michigan State University East Lansing MI 48824-1312 USA Cell and molecular Biology Program Michigan State University East Lansing MI 48824 USA Department of Energy-Plant Research Laboratory Michigan State University East Lansing MI 48824 USA Genetics Program Michigan State University East Lansing MI 48824 USA Biochemistry and molecular Biology Program Michigan State University East Lansing MI 48824 USA Present address: The Salk Institute for Biological Studies Plant Molecular and Cellular Biology Laboratory La Jolla CA 92037 USA Present address: mycobacteria and Brucella Section NVSL/APHIS/USDA 1920 Dayton Ave Ames IA 50010 USA

FtsZ1 and FtsZ2 are phylogenetically distinct families of FtsZ in plants that co-localize to mid-plastid rings and facilitate division of chloroplasts. In plants, altered levels of either FtsZ1 or FtsZ2 cause dose-dependent defects in chloroplast division; thus, studies on the functional relationship between FtsZgenes require careful manipulation of FtsZ levels in vivo. To define the functional relationship between the two FtsZ2 genes in Arabidopsis thaliana, FtsZ2-1 and FtsZ2-2, we expressed FtsZ2-1 in an ftsZ2-2 null mutant, and vice versa, and determined whether the chloroplast division defects were rescued in plants expressing different total levels of FtsZ2. Full rescue was observed when either the FtsZ2-1 or FtsZ2-2 level approximated total FtsZ2 levels in wild-type （WT）. Additionally, FtsZ2-2 interacts with ARC6, as shown previously for FtsZ2- 1. These data indicate that FtsZ2-1 and FtsZ2-2 are functionally redundant for chloroplast division in Arabidopsis. To rigorously validate the requirement of each FtsZ family for chloroplast division, we replaced FtsZ1 with FtsZ2 in vivo, and vice versa, while maintaining the FtsZ level in the transgenic plants equal to that of the total level in WT. Chloroplast division defects were not rescued, demonstrating conclusively that FtsZ1 and FtsZ2 are non-redundant for maintenance of WT chloroplast numbers. Finally, we generated ftsZtriple null mutants and show that plants completely devoid of FtsZ protein are viable and fertile. As plastids are presumably essential organelles, these findings suggest that an FtsZ-independent mode of plastid partitioning may occur in higher plants.

关键词： Chloroplast plastid division FtsZ ARC6 PDV1.

An in situ monitoring campaign of a hard rock pillar at great depth within a Canadian mine

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journal of Rock mechanics and Geotechnical Engineering 2020年第3期12卷 427-448页

作者： bradley Forbes Nicholas Vlachopoulos mark S.Diederichs Andrew j.Hyett Allan Punkkinen Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonOntarioK7L 3N6Canada Department of Civil Engineering Royal Military College of CanadaKingstonOntarioK7K 7B4Canada YieldPoint Inc. KingstonOntarioK7M 4W9Canada Normet Canada Ltd. LivelyOntarioP3Y 0B3Canada

A recent research campaign at a Canadian nickel-copper mine involved instrumenting a hard rock sill drift pillar with an array of multi-point rod extensometers,distributed optical fibre strain sensors,and borehole pressure cells(BHPCs).The instrumentation spanned across a 15.24 m lengthwise segment of the relatively massive granitic pillar situated at a depth of 2.44 km within the *** may 2016 and march 2017,the pillar’s displacement and pressure response were measured and correlated with mining activities on the same level as the pillar,including:(1)mine-by of the pillar,(2)footwall drift development,and(3)ore body stoping *** displacements of the pillar,the extensometers provided high temporal resolution(logged hourly)and the optical fibre strain sensors provide high spatial resolution(measured every 0.65 mm along the length of each sensor).The combination of sensing techniques allowed centimetre-scale rock mass bulking near the pillar sidewalls to be distinguished from microstrain-scale fracturing towards the core of the ***,the influence and extent of a mine-scale schistose shear zone transecting the pillar was *** converting measured rock mass displacement to velocity,a process was demonstrated which allowed mining activities inducing displacements to be categorised by time-duration and cumulative *** over half of the analysed mining activities,displacements were determined to prolong for over an hour,predominately resulting in submillimetre cumulative displacements,but in some cases multi-centimetre cumulative displacements were *** time-dependent behaviour was more pronounced within the vicinity of the plumb shear *** measurements were also used to assess selected support member load and elongation mobilisation per mining *** was found that a combined static load and elongation capacity of reinforcing members was essential to maintaining excavation stability,while

关键词： Hard rock pillar Rockburst Rock mass bulking Distributed optical fibre strain sensing Extensometer In situ monitoring High stress dynamic support

Recent Developments in metallic Degradable micromotors for Biomedical and Environmental Remediation Applications

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Nano-micro Letters 2024年第3期16卷 1-35页

作者： Sourav Dutta Seungmin Noh Roger Sanchis Gual Xiangzhong Chen Salvador Pané bradley j.Nelson Hongsoo Choi Department of Robotics and mechatronics Engineering Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea DGIST‑ETH microrobotics Research Center DGISTDaegu 42988Republic of Korea multi‑Scale Robotics Lab Institute of Robotics and Intelligent SystemsETH Zurich8092 ZurichSwitzerland Institute of Optoelectronics State Key Laboratory of Photovoltaic Science and TechnologyShanghai Frontiers Science Research Base of Intelligent Optoelectronics and PerceptionFudan UniversityShanghai 200433People’s Republic of China

Synthetic micromotor has gained substantial attention in biomedicine and environmental ***-based degradable micromotor composed of magnesium(mg),zinc(Zn),and iron(Fe)have promise due to their nontoxic fuel-free propulsion,favorable biocompatibility,and safe excretion of degradation products Recent advances in degradable metallic micromotor have shown their fast movement in complex biological media,efficient cargo delivery and favorable biocompatibility.A noteworthy number of degradable metal-based micromotors employ bubble propulsion,utilizing water as fuel to generate hydrogen *** novel feature has projected degradable metallic micromotors for active in vivo drug delivery *** addition,understanding the degradation mechanism of these micromotors is also a key parameter for their design and *** propulsion efficiency and life span govern the overall performance of a degradable metallic *** we review the design and recent advancements of metallic degradable ***,we describe the controlled degradation,efficient in vivo drug delivery,and built-in acid neutralization capabilities of degradable micromotors with versatile biomedical ***,we discuss micromotors’efficacy in detecting and destroying environmental ***,we address the limitations and future research directions of degradable metallic micromotors.

关键词： magnesium Zinc Iron Biodegradable microrobot Biomedical Environmental

Linking uplift and mineralisation at the mount Novit Zn-Pb-Ag Deposit,Northern Australia:Evidence from geology,U-Pb geochronology and sphalerite geochemistry

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Geoscience Frontiers 2022年第2期13卷 333-350页

作者： bradley Cave William Perkins Richard Lilly Department of Earth Sciences University of AdelaideAdelaideSAAustralia Geological Survey of Queensland BrisbaneQLDAustralia

The subeconomic mount Novit Zn-Pb-Ag deposit is located approximately 20 km south of mount Isa,*** contrast to the nearby mount Isa,Hilton and George Fisher Zn-Pb-Ag deposits,mineralisation at mount Novit is situated to the west of the regional-scale mount Isa Fault and is hosted in the moondarra Siltstone as opposed to the Urquhart ***-grade(mineralisation primarily replaces pre-existing carbonate alteration and veining and consists of pyrrhotite,pyrite and sphalerite with lesser ***-grade(>10 wt.%Zn+Pb)mineralisation occurs as a matrix supported breccia dominated by sphalerite and pyrrhotite with galena,pyrite,and ***-situ U-Pb geochronology was completed on apatite and two textural varieties of ***-grained(m)subhedral to anhedral monazite is located within highly foliated biotite alteration directly adjacent Zn-Pb-Ag mineralisation and yields a mean weighted^(207)Pb/^(206)Pb age of 1527±18 ma(mSWD=1.06).This age is consistent with the formation of highly foliated biotite alteration during D;deformation of the Isan *** from the same fabric yields a lower intercept age of1443±29 ma(mSWD=1.30).Consistent with previous studies,this age is interpreted to represent the age of a major thrusting event along the mount Isa Fault that resulted in the cooling of the mount Novit area below~375℃.Coarse-grained monazite is coeval with Zn-Pb-Ag mineralisation and yields a mean weighted^(207)Pb/^(206)Pb age of 1457±11 ma(mSWD=0.28).Sphalerite from mount Novit has low concentrations(m)of Ge and Ga and a relatively high concentration of In(5 to>10 ppm),possibly reflecting the leaching of the metals from an underlying basement *** GGImFis geothermometer(Frenzel et al.,2016)produced a mean formation temperature of 345±52℃.The timing and temperature of Zn-Pb-Ag mineralisation is consistent with the age and cooling temperature of apatite presented in this *** on these correlations,we

关键词： mount Isa mount Novit Zn-Pb-Ag mineralisation monazite Apatite Geochronology

Informing management of rare species with an approach combining scenario modeling and spatially explicit risk assessment

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Ecosystem Health and Sustainability 2015年第6期1卷 9-26页

作者： jennifer m.Duggan bradley A.Eichelberger Shan ma joshua j.Lawler Guy Ziv School of Environmental and Forest Sciences University of WashingtonSeattleWashington 98195 USA Natural Capital Project Stanford UniversityStanfordCalifornia 94305 USA School of Geography University of LeedsLeeds LS29J TUnited Kingdom Division of Science and Environmental Policy California State University Monterey BaySeasideCalifornia 93955 USA

Wildlife managers are tasked with identifying and managing stressors that threaten persistence of *** demonstrate an approach to land-use planning that combines scenario modeling and ecological risk assessment to map and quantify risk to population persistence for three rare prairie species in Washington State,*** corroboration of model output,we found that of the management scenarios considered,only a scenario with year-round restrictions on use of off-road vehicles,digging,and camping enforced in all potential habitat reduces risk to the *** risk is focused primarily in two patches of prairie habitat in our study area,indicating stringent restrictions need not be applied ***,one area is not easily accessed by two of the three species considered,suggesting reintroductions to suitable but inaccessible habitat may play an important role in management of these *** analyses suggest changes in land use and management that might improve habitat for rare species,with options for minimizing monetary and social *** the proposed approach relies on hypothetical management scenarios and uses a model flexible in data requirements to provide spatially explicit output,it can be used to inform adaptive management of rare species in diverse land-planning processes and will be especially useful when management decisions must be made under time or cost constraints.

关键词： adaptive management land-useplanning mazamapocketgopher(Thomomysmazama) military training PugetSoundprairie rarespeciesmanagement riskassessment scenariomodeling Scotchbroom(Cytisus scoparius) spatiallyexplicitmodel StreakedHornedLark(Eremophilaalpestrisstrigata) Taylor’scheckerspot butterfly(Euphydryasedithataylori)

Surgeon preferences in the treatment of thumb carpometacarpal osteoarthritis

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World journal of Orthopedics 2024年第5期15卷 435-443页

作者： Edward j Wu bradley W Fossum Wyatt Vander Voort Christopher O Bayne Robert m Szabo Department of Orthopedic Surgery University of Minnesota Medical SchoolMinneapolisMN 55455United States Department of Orthopaedic Surgery UC Davis School of MedicineSacramentoCA 95817United States

BACKGROUND Primary thumb carpometacarpal(CmC)osteoarthritis is one of the most common conditions encountered by hand *** the vast number of operations that have been proposed,none have demonstrated results significantly superior to trapeziectomy *** The purpose of our study was to determine why surgeons opt for their technique in treating CmC *** A cross-sectional survey of active members of the American Society for Surgery of the Hand was conducted to evaluate the reasons behind their preferred technique in the treatment of isolated thumb CmC *** were contacted by email once and provided with a link to a de-identified survey consisting of 5 treatment questions and 5 demographic *** Of 950 responses were received.40.5%of surgeons preferred trapeziectomy+ligament reconstruction tendon interposition(LRTI),followed by trapeziectomy+suspensionplasty(28.2%),suture button suspension(5.9%),trapeziectomy alone(4.6%),prosthetic arthroplasty(3.2%),arthrodesis(1.1%),and other(6.6%).Proponents of trapeziectomy+LRTI cited familiarity(73.2%),exposure during fellowship(48.8%)and less proximal migration(60%)to be the main reasons affecting their *** who preferred trapeziectomy+suspensionplasty most reported simplicity(74.9%),fewer complications(45.3%),less proximal migration(43.8%),and avoidance of autogenous tissue harvest(42.7%).Advocates of suture button suspension cited avoidance of autogenous tissue harvest(80.4%),shorter immobilization(76.8%),and quicker recovery(73.2%)with their *** of trapeziectomy alone cited simplicity(97.7%),fewer complications(86.4%),and avoidance of autogenous tissue harvest(59.1%).In their comments,45%of surgeons choosing trapeziectomy alone cited evidence as an additional *** of prosthetic arthroplasty cited improved pinch strength(83.3%)and improved range of motion(63.3%),while those preferring arthrodesis cited better pinch strength(90%)and freque

关键词： Thumb carpometacarpal Osteoarthritis Trapeziectomy Ligament reconstruction tendon interposition Suspensionplasty Preferences Trends

Auxin EvoDevo: Conservation and Diversification of Genes Regulating Auxin Biosynthesis, Transport, and Signaling

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molecular Plant 2019年第3期12卷 298-320页

作者： michaela Sylvia matthes Norman bradley Best janlo m.Robil Simon malcomber Andrea Gallavotti Paula mcSteen Division of Biological Sciences Interdisciplinary Plant Group and Missouri Maize CenterUniversity of Missouri-Columbia301 Christopher Bond Life Sciences CenterColumbiaMO 65211USA Department of Biological Sciences California State UniversityLongBeachCA 90840USA Waksman Institute of microbiology Rutgers UniversityPiscatawayNJ 08854-8020USA Department of Plant Biology Rutgers UniversityNew BrunswickNJ 08901USA Present address:National Science Foundation 2415 Eisenhower AvenueAlexandriaVA 22314USA

The phytohormone auxin has been shown to be of pivotal importance in growth and development of land *** underlying molecular players involved in auxin biosynthesis, transport, and signaling are quite well understood in ***, functional characterizations of auxin-related genes in economically important crops, specifically maize and rice, are still *** this article, we comprehensively review recent functional studies on auxirelated genes in both maize and rice, compared with what is known in Arabidopsis, and highlight conservation and diversification of their functions. Our analysis is illustrated by phylogenetic analysis and publicly available gene expression data for each gene family, which will aid in the identification of auxin-related genes for future *** challenges and future directions for auxin research in maize and rice are *** in gene editing techniques provide powerful tools for overcoming the issue of redundancy in these gene families and will undoubtedly advance auxin research in crops.

关键词： auxin maize Arabidopsis rice