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Putting the brakes on chloroplast stress signaling

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Molecular Plant 2022年第3期15卷 388-390页

作者： david W.Tano Jesse d.Woodson The School of Plant Sciences University of Arizona303 Forbes Hall1140 E.South Campus DriveTucsonAZUSA

As sessile organisms,plants must be able to sense their surroundings and *** way plants do this is by using their energy-producing organelles(chloroplasts and mitochondria).during environmental stress,these organelles experience metabolic changes that induce signals for *** many metabolites have been proposed as signaling factors,reactive oxygen species(ROS)are known to play prominent *** the chloroplast,the ROS singlet oxygen(^(1)O_(2))is naturally produced during impaired photosynthesis and can lead to retrograde signaling to the nucleus(to control the expression of hundreds of genes),chloroplast degradation,and cell death.

关键词： organelle stress hundreds

Sorption of inorganic nanoparticles in woven cellulose fabrics

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Particuology 2009年第2期7卷 121-128页

作者： dan H. Marsh d. Jason Riley david York Andrew Graydon School of Chemistry University of NottinghamUniversity ParkNottinghamNG7 the School of Chemistry University of BristolCantocks CloseBristolBS8 1TSUK.2RDUK department of Materials Imperial College LondonExhibition RoadLondonSW7 2AZUK the School of Chemistry University of BristolCantocks CloseBristolBS8 1TSUK. Procter & Gamble Technical Centres Ltd. Newcastle Upon TyneNE12 9TSUK

Titanium dioxide was deposited from aqueous suspension onto cellulosic surfaces. Titania was sourced from degussa （P25TM, 70：30 anatase：rutile）. dry uptake of particles was shown to be rapid and dominant with one-third of the deposition occurring in less than 30 s and over one-half in the first minute. Isotherms were recorded to compare the rate of titanium deposition on dry and pre-wetted cotton. In the dry case uptake reached a maximum in 30 min whereas in the pre-wetted case the uptake was seen to continue beyond 180 min. A broad trend of higher deposition occurring at lower pH was seen, corresponding to the region where surface charges were opposite and thus attractive. dry pickup was less significant at high pH. The response to varying ionic strength was complex and was attributed to the combined effect of charge screening, particle aggregation and consequent particle entrapment or occlusion. Titania deposition into the interstices of woven cotton sheets resulted in the formation of inorganic, nanoparticulate skeletons which could be isolated by controlled combustion of the cellulose and thus cotton was suggested to have potential for the templated synthesis of high surface area semiconductor materials.

关键词： Titania Cellulose Sorption Zeta potential Templated material

Monte Carlo sampling for error propagation in linear regression and applications in isochron geochronology

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Science Bulletin 2019年第3期64卷 189-197页

作者： Yang Li Shuang Zhang Richard Hobbs Camila Caiado Adam d.Sproson david Selby Alan d.Rooney State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences department of Earth Sciences Durham University department of Geology and Geophysics Yale University department of Mathematical Sciences Durham University Atmosphere and Ocean Research Institute The University of Tokyo

Geochronology is essential for understanding Earth's history. The availability of precise and accurate isotopic data is increasing; hence it is crucial to develop transparent and accessible data reduction techniques and tools to transform raw mass spectrometry data into robust chronological data. Here we present a Monte Carlo sampling approach to fully propagate uncertainties from linear regressions for isochron dating. Our new approach makes no prior assumption about the causes of variability in the derived chronological results and propagates uncertainties from both experimental measurements(analytical uncertainties) and underlying assumptions(model uncertainties) into the final age *** synthetic examples, we find that although the estimates of the slope and y-intercept(hence age and initial isotopic ratios) are comparable between the Monte Carlo method and the benchmark‘‘Isoplot" algorithm, uncertainties from the later could be underestimated by up to 60%, which are likely due to an incomplete propagation of model uncertainties. An additional advantage of the new method is its ability to integrate with geological information to yield refined chronological constraints. The new method presented here is specifically designed to fully propagate errors in geochronological applications involves linear regressions such as Rb-Sr, Sm-Nd, Re-Os, Pt-Os, Lu-Hf, U-Pb(with discordant points),Pb-Pb and Ar-Ar.

关键词： Linear regression Isochron Geochronology Uncertainty propagation Monte Carlo Isoplot

Impact of Brunswick River Mouth Training Walls on Adjacent Beaches,Brunswick Heads,New South Wales,Australia

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海洋工程：英文版 2004年第2期18卷 207-220页

作者：黄海军 Andrew d.SHORT Thomas ZENG david HANSLOW Institute of Oceanology Coastal Studies Unit department of Land and Water Conservation

River training walls have been built at scores of locations along the NSW coast and their impacts on shoreline change are still not fully understood. In this study, the Brunswick River entrance and adjacent beaches are selected for examination of the impact of the construction of major training walls. Thirteen sets of aerial photographs taken between 1947 and 1994 are used in a GIS approach to accurately determine the shoreline position, beach contours and sand volumes, and their changes in both time and space, and then to assess the contribution of both the structures and natural hydrodynamic conditions to large scale (years-decades and kilometres) beach changes. The impact of the training walls can be divided into four stages: natural conditions prior to their construction (pre 1959), major downdrift erosion and updrift accretion during and following the construction of the walls in 1959～1962 and 1966, diminishing impact of the walls between 1966 and 1987, and finally no apparent impact between 1987～1994. The impact extends horizontally about 8 km updrift and 17 km downdrift, and temporally up to 25 years.

关键词： human structure beach erosion and accretion beach downdrift/updrift shoreline change GIS

Influence of deviatoric stress on rockburst occurrence:An experimental study

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International Journal of Mining Science and Technology 2018年第5期28卷 763-766页

作者： Thomas Bruning Murat Karakus Selahattin Akdag Giang d.Nguyen david Goodchild School of Civil Environmental and Mining EngineeringThe University of AdelaideAdelaide 5005Australia OZ Minerals 2 Hamra DriveAdelaide AirportSA5950Australia

As mining delves deeper into the crust, it is necessary to investigate the complex rock responses associated with higher stress gradients. Therefore, it is essential to better understand the mechanisms associated with the rockburst phenomenon. However, due to the large-scale and difficult monitoring of real mining excavations, laboratory scale tests must be utilised to determine the conditions conducive to burst. To this end, this research focuses on the implementation of a new rockburst testing apparatus to replicate the stress conditions of a rock mass excavation at the time of bursting. This apparatus allows the determination of rockburst stresses and a relationship between deviatoric stress and in-situ pressure/depth. Using this relationship it is then possible to estimate the standardised stress levels for a certain rock type which might lead to rockburst occurrence. Furthermore, it is demonstrated that with increasing in-situ pressure, the likelihood(measured as a lower differential stress) and the extent(indicated by the increasing range of deviatoric stress) of rockburst increases. These findings provide valuable information about the conditions necessary for bursting in deep mining.

关键词： Rockburst test Hollow cylinder Hard rock In-situ stress

Intense pulsed light‑based treatment for the improvement of symptoms in glaucoma patients treated with hypotensive eye drops

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Eye and Vision 2024年第2期10卷 12-21页

作者： Jose Maria Martinez‑de‑la‑Casa Carlos Oribio‑Quinto Almudena Milans‑del‑bosch Pilar Perez‑Garcia Laura Morales‑Fernandez Javier Garcia‑Bella Jose Manuel Benitez‑del‑Castillo Julian Garcia‑Feijoo david P.Pinero Ophthalmology Unit Department of Ophthalmology and ORLFaculty of MedicineHospital Clinico San-CarlosUniversidad Complutense de MadridInstituto de Investigacion Sanitaria del Hospital Clinico San-Carlos(IdISSC)28040 MadridSpain department of Immunology Ophthalmology and ORLSchool of MedicineInstituto de Investigaciones Oftalmologicas Ramon CastroviejoUniversidad Complutense de MadridMadridSpain department of Optics Pharmacology and AnatomyUniversity of AlicanteAlicanteSpain

Background:Ocular surface disease in glaucoma patients is a significant ocular co-morbidity that can affect 40%to 59%of these patients *** current study was aimed at evaluating the potential clinical benefit of an intense pulsed light(IPL)-based treatment in glaucomatous patients with ocular surface disease due to prolonged hypotensive eyedrop *** our knowledge,this is the first series analyzing the therapeutic effect of this treatment option in this type of ***:This non-comparative prospective case series study enrolled a total of 30 glaucoma patients ranging in age from 57 to 94 years old and treated with hypotensive eyedrops for years with dry eye *** patients received four sessions of IPL treatment using the Optima IPL system(Lumenis,Yokneam,Israel)adjusted to the official optimized Lumenis *** in symptomatology,corneal staining,conjunctival hyperemia,non-invasive break-up time(NIBUT),tear osmolarity,tear meniscus height(TMH),meiboscore and meibomian gland expressibility was analyzed after ***:Statistically significant reductions were observed after IPL treatment in the symptomatology scores measured with different questionnaires[ocular surface disease index(OSdI),standard patient evaluation of eye dryness(SPEEd)and symptom assessment questionnaire in dry eye(SANdE)]as well as with the visual analogue scale(PdI was−15.0±11.3.A significant reduction was found after treatment in the corneal staining score(Pduction was found in tear film meniscus height(P=0.012),as well as in tear film osmolarity(P=0.001).A significant reduction was also found in meibomian gland expressibility(P=0.003),changing the percentage of grade 3 eyes from 44.4%before IPL to 17.2%after ***:IPL therapy combined with meibomian gland expression(MGX)seems to be an effective option to improve symptomatology in glaucomatous patients with ocular surface diseas

关键词： Glaucoma Intense pulsed light dry eye Meibomian glands

Population collapses in the pre-modern period:case study of the Fuping County, Northwest China

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Chinese Journal of Population,Resources and Environment 2017年第4期15卷 365-373页

作者： Jie Fei david d.Zhang Institute of Chinese Historical Geography Fudan University department of Geography The University of Hong Kong

The pre-modern history of population change in the Fuping County(Shaanxi Province, China)during the Ming and Qing dynasties(Ad 1368-1911) was reconstructed using historical *** Fuping County experienced two major population collapses, i.e. the late Ming dynasty(1550-1640 s) and the 1860-1880 s. The first one was caused by the great Ad 1556 earthquake and the extreme droughts and warfare in the 1630-1640 s. The second one was caused by warfare and extreme droughts. As a whole, natural disasters, including extreme drought and great earthquake, were the key direct causes of population collapse, and climatic cooling would be a potential indirect cause. It is very interesting that population collapses occurred almost synchronously in the Fuping County and whole China, and the trends of population change were also very similar. Climate-population relationship in China would be valid at finer geographic level,and climatic cooling could be a potential indirect cause of population collapse.

关键词： Population collapse FupingCounty earthquake extreme drought

Controlling human platelet activation with calcium-binding nanoparticles

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Nano Research 2020年第10期13卷 2697-2705页

作者： david Cabrera Karen Walker Sandhya Moise Neil d.Telling Alan G.S.Harper School of Pharmacy and Bioengineering Keele UniversityGuy Hilton Research CenireThormburrow DriveHartshill Stoke-on Trent ST47QBUK ?Central Electron Microscope Unit School of Life SciencesKeele UniversityNewcastle-under LIymeStaffordshireST55BGUK department of Chemical Engineering University of BathBath BA27AYUK School of Medicine Keele UniversityNewcastle-under-LymeStaffordshireST55BGUK

Human platelets aggregate at sites of blood vessel damage in response to a rise in their cytosolic calcium *** these cytosolic calcium rises would provide a method to inhibit platelet activation and prevent the unwanted blood clots that causes heart attack and *** we have predicted that calcium accumulation within the lumen of an infolded portion of the platelet plasma membrane called the open canalicular system(OCS)is essential for maintaining this cytosolic calcium *** to its nanometer dimensions of the OCS,it has been difficult to measure or interfere with the predicted luminal calcium *** we utilise iron oxide magnetic nanoparticles coated with the known calcium chelator,citrate,to create calcium-binding *** were used to assess whether an OCS calcium store plays a role in controlling the dynamics of human platelet activation and *** demonstrate that citrate-coated nanoparticles are rapidly and selectively uptaken into the OCS of activated human platelets,where they act to buffer the accumulation of calcium *** with these calcium-binding nanoparticles reduced thrombin-evoked cytosolic calcium rises,and slowed platelet aggregation and clot retraction in human *** contrast,nanoparticles that cannot bind calcium have no *** study demonstrates that the OCS acts as a key source of calcium for maintaining cytosolic calcium rises and accelerating platelet aggregation,and that calcium-binding nanoparticles targeted to the OCS could provide an anti-platelet therapy to treat patients at risk of suffering heart attacks or strokes.

关键词： nanochelators human platelets open canalicular system calcium signaling nanoparticles

History and evaluation of national-scale geochemical data sets for the United States

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Geoscience Frontiers 2013年第2期4卷 167-183页

作者： david B.Smith Steven M.Smith John d.Horton U.S.Geological Survey.denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated by a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous *** National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous *** *** sampled area represented about 65%of the *** Natural Resources Conservation Service（NRCS）,from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous *** data set contains analyses of more than 3000 *** National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the *** covered by the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** USGS,in collaboration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** paper（1） discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and（2） evaluates each data set in terms

关键词： Geochemical mapping National-scale geochemical data Geochemical baselines United States