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2002

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Arkansas Water Resources Center Annual Technical Report, 2002, Arkansas Water Resources Center Dec 2002

Arkansas Water Resources Center Annual Technical Report, 2002, Arkansas Water Resources Center

Arkansas Water Resources Center Annual Report

No abstract provided.

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An Invariance Transformation Algorithm For Defect Characterization Of Ultrasonic Signals For The Nondestructive Evaluation Of Concrete, Michael Dominic Ciocco Dec 2002

An Invariance Transformation Algorithm For Defect Characterization Of Ultrasonic Signals For The Nondestructive Evaluation Of Concrete, Michael Dominic Ciocco

Theses and Dissertations

Nondestructive evaluation (NDE) techniques offer cost-effective strategies for monitoring the integrity of a variety of civil infrastructure, such as natural gas and sewer pipelines, without the need to take the system off-line. However, interpretation of NDE signals in terms of the location, size, and shape of underlying flaws in the material being inspected is fraught with difficulty. Typically, variations in the testing signal due to operational parameters have created a significant challenge for defect characterization. This thesis proposes, develops, and validates a defect characterization algorithm that compensates for operational variables and maps the test signal to a visual defect profile. …

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Automated Segmentation Of Radiodense Tissue In Digitized Mammograms Using A Constrained Neyman-Pearson Classifier, Jeremy Thomas Neyhart Dec 2002

Automated Segmentation Of Radiodense Tissue In Digitized Mammograms Using A Constrained Neyman-Pearson Classifier, Jeremy Thomas Neyhart

Theses and Dissertations

Breast cancer is the second leading cause of cancer related mortality among American women. Mammography screening has emerged as a reliable non-invasive technique for early detection of breast cancer. The radiographic appearance of the female breast consists of radiolucent (dark) regions and radiodense (light) regions due to connective and epithelial tissue. It has been established that the percentage of radiodense tissue in a patient's breast can be used as a marker for predicting breast cancer risk. This thesis presents the design, development and validation of a novel automated algorithm for estimating the percentage of radiodense tissue in a digitized mammogram. …

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Limits On Extra Dimensions And New Particle Production In The Exclusive Photon, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Dec 2002

Limits On Extra Dimensions And New Particle Production In The Exclusive Photon, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

The exclusive γE/T signal has a small standard model cross section and is thus a channel sensitive to new physics. This signature is predicted by models with a superlight gravitino or with large extra spatial dimensions. We search for such signals at the Collider Detector at Fermilab, using 87   pb-1 of data at √s=1.8   TeV, and extract 95% C.L. limits on these processes. A limit of 221 GeV is set on the scale |F|1/2 in supersymmetric models. For 4, 6, and 8 extra dimensions, model-dependent limits on the fundamental mass scale MD of 0.55, 0.58, and …

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Analysis Of The Optimisation Of Berth Allocation : Berth Allocation With An External Terminal Facility, H.J.K.U. Kumara Dec 2002

Analysis Of The Optimisation Of Berth Allocation : Berth Allocation With An External Terminal Facility, H.J.K.U. Kumara

World Maritime University Dissertations

No abstract provided.

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The Validity Of Oil Spill Combating Methods : The Decision Making Process : A Critical Study, Mohab Mahmoud Abou-Elkawam Dec 2002

The Validity Of Oil Spill Combating Methods : The Decision Making Process : A Critical Study, Mohab Mahmoud Abou-Elkawam

World Maritime University Dissertations

No abstract provided.

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Viscoelasticity From A Microscopic Model Of Dislocation Dynamics, M. Christina Marchetti, Karl Saunders Dec 2002

Viscoelasticity From A Microscopic Model Of Dislocation Dynamics, M. Christina Marchetti, Karl Saunders

Physics

It is shown that the dynamics of a viscoelastic medium can be modeled as that of a two-dimensional crystal with a finite concentration of dislocations, as well as vacancy and interstitial defects. At the longest length scales the viscoelasticity is described by the simplest Maxwell model, whose shear and compressional relaxation times are obtained in terms of microscopic quantities, including the density of free dislocations. At short length scales, t bond orientational order effects become important and lead to wave vector dependent corrections to the relaxation times.

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Mylanodon Rosei, A New Metacheiromyid (Mammalia: Palaeanodonta) From The Late Tiffanian (Late Paleocene) Of Northwestern Wyoming, Ross Secord, Philip D. Gingerich, Jonathan I. Bloch Dec 2002

Mylanodon Rosei, A New Metacheiromyid (Mammalia: Palaeanodonta) From The Late Tiffanian (Late Paleocene) Of Northwestern Wyoming, Ross Secord, Philip D. Gingerich, Jonathan I. Bloch

Department of Earth and Atmospheric Sciences: Faculty Publications

Mylanodon rosei is a new genus and species of late Paleocene metacheiromyid palaeanodont from a new late Tiffanian locality, Y2K Quarry, in the Clarks Fork Basin, Wyoming. The type is an adult dentary with P4 and a molariform double-rooted M1. This provides the first evidence that molariform teeth were retained in early Metacheiromyidae. A second specimen is a juvenile dentary with a partial P3 and an unerupted P4. This is the first juvenile dentition known for a Paleocene metacheiromyid. The new specimens enable determination of dental homologies. Reduction of teeth in early metacheiromyids took …

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Search For Radiative B,-Hadron Decays In Pp̅ Collisions At √S=1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Dec 2002

Search For Radiative B,-Hadron Decays In Pp̅ Collisions At √S=1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We have performed a search for radiative b-hadron decays using events produced in pp̅ collisions at √s=1.8 TeV and collected by the Collider Detector at Fermilab. The decays we considered were B̅d0→K*0(→K-π+) γ, B̅s0→φ(→K+K-) γ, Λb0→ Λ(→pπ-) γ, and their charge conjugates. Two independent methods to identify photons from such decays were employed. In the first method, the photon was detected in the electromagnetic calorimeter. In the second method, the photon was identified …

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Loading Microcolumns For The Separation Of Analytes From A Sample In The Millisecond Time Scale, David S. Hage, William A. Clarke Dec 2002

Loading Microcolumns For The Separation Of Analytes From A Sample In The Millisecond Time Scale, David S. Hage, William A. Clarke

David Hage Publications

The present invention generally relates to a microcolumn capable of separating an analyte from a sample in the millisecond time domain. The microcolumn is capable of such rapid separation by employing small column volumes that can tolerate medium to high flow rates. The invention also relates to a method of loading a microcolumn capable of separating an analyte from a sample in the millisecond time domain using plural injections of the packing material.

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Optimal Pumping Strategies For Umatilla Chemical Depot Rdx And Tnt Plumes, Richard C. Peralta Dec 2002

Optimal Pumping Strategies For Umatilla Chemical Depot Rdx And Tnt Plumes, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We present optimal pumping strategies to address RDX and TNT plumes at Umatilla Chemical Depot (UCD). We provide strategies for four optimization problem formulations. Each strategy requires constructing 2 wells. New Well U-1 is in the same location for all strategies. The second well location can differ with formulation. The number in a strategy’s name refers to the formulation it addresses. Using optimization in design is normally an iterative process involving interaction between the designer and client after preliminary optimizations are performed. This project does not permit that. To compensate, we present a second strategy for Formulation 1 (Strategy USU1B), …

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A Model For Measuring Quality Of Port Services In A Container Terminal, Ali Akbar Safaei Dec 2002

A Model For Measuring Quality Of Port Services In A Container Terminal, Ali Akbar Safaei

World Maritime University Dissertations

No abstract provided.

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Morphometrics Of The Pancake Tortoise (Malacochersus Tornieri) In Tanzania, J. Kabigumila Dec 2002

Morphometrics Of The Pancake Tortoise (Malacochersus Tornieri) In Tanzania, J. Kabigumila

Tanzania Journal of Science

Observations were made of the morphometrics of captive pancake tortoise (Malacochersus tornieri) in June 1995. Carapace length ranges for immature tortoises and adult males and females were 50-115, 123-160 and 129-171 mm respectively. The respective carapace widths were 45-90, 97-130, and 92-129 and 97-130 mm. Carapace height ranges were 15-29, 25-40 and 117-159 mm, respectively, while plastron length ranges were 45-110, 108-150 and 117-159 mm. The relationships between carapace length and width (males: y = 13.763+0.639x; females: y = 17.302+0.639x) and height (males: y=6.851+0.170x, females: y = 17.274+0.170x) were isometric and sexually dimorphic in adults. The relationship between carapace length …

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Engineering Geological Mapping Of Dar Es Salaam City, Tanzania, K. A. Msindai Dec 2002

Engineering Geological Mapping Of Dar Es Salaam City, Tanzania, K. A. Msindai

Tanzania Journal of Science

Engineering geological mapping of Dar es Salaam city in Tanzania has been carried out using desk studies supplemented by field reconnaissance as well as limited laboratory tests. Desk studies involved interpretation of medium to large-scale topographical maps, Landsat imagery and sequential aerial photographs from 1953-1990. These studies also evaluated small to medium scale geological, pedological maps together with ground water data from 50 boreholes. Two basic maps were prepared, namely, geomorphological and geological map depicts the spatial extent of the Neogene geological formations. Three distinct sandstone terraces could be distinguished in Dar es Salaam region at 0-15 m and 30 …

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Organochlorine Pesticides In Residues In Waters From The Coastal Area Of Dar Es Salaam And Their Effect On Aquatic Biota, H Mwevura, Oc Othman, Gl Mhehe Dec 2002

Organochlorine Pesticides In Residues In Waters From The Coastal Area Of Dar Es Salaam And Their Effect On Aquatic Biota, H Mwevura, Oc Othman, Gl Mhehe

Tanzania Journal of Science

Water samples from Msimbazi and Kizinga rivers in Dar es Salaam and from the coastal marine environment receiving waters from these rivers were analyzed for various organochlorine pescticide residues using GC-ECD and GC-MS. p,p'-DDE, p,p'-DDT, dieldrin and γ-HCH were the only organochlorine pesticide residues detected at significantly greater concentrations above the detection limits. There was a marked difference in the frequency of pesticide residue detection during the dry and wet seasons. All the wet season samples and 37.5% of the dry season samples revealed presence of p,p-DDE at concentrations ranging from 0.05 to 0.45 mgl-1 and 0.08 to 0.20 mgl-1 …

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Spatial-Temporal Changes In Phytoplankton Biomass And Primary Production In Chwaka Bay, Zanzibar, M. N. S. Kyewalyanga Dec 2002

Spatial-Temporal Changes In Phytoplankton Biomass And Primary Production In Chwaka Bay, Zanzibar, M. N. S. Kyewalyanga

Tanzania Journal of Science

Spatial-temporal variations in phytoplankton primary production (PP) and biomass (B) were studied for a period of about one year, from July 1999 to July 2000. In addition, changes in corresponding environmental variables were examined. Sampling took place at two stations in Chwaka Bay, one located in mangrove areas, Station I, and the other in an open area, Station II. Although there were changes both with location and time, there were no clear seasonal trends. Generally, the phytoplankton biomass and primary production (mg C m-3 h-1) were higher at Station I than at Station II. However, specific production, that is, primary …

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Assessment Of Wind Energy Potential For Eletricity Generation In Setchet, Hanang, Tanzania, A. S. Kasasi, R. M. Kainkwa Dec 2002

Assessment Of Wind Energy Potential For Eletricity Generation In Setchet, Hanang, Tanzania, A. S. Kasasi, R. M. Kainkwa

Tanzania Journal of Science

Tanzania depends heavily on hydropower for her electricity demand and experiences power shortage during the dry seasons. Wind energy is proposed as an alternative source of electricity to the fossil fuel generators during the dry season, the latter are normally used to supplement the shortfall in hydro-electricity generation. Fossil fuel generators produce emissions that are toxic and as such degrade the environment. Wind speed data from a site called Setchet is used to illustrate that the available wind energy can be harvested to generate electricity that can supplement the shortfall of electricity. The windy season, which is from July to …

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Structural Evolution Of The Kilombero Rift Basin In Central Tanzania, A. H. Mruma Dec 2002

Structural Evolution Of The Kilombero Rift Basin In Central Tanzania, A. H. Mruma

Tanzania Journal of Science

Detailed geological and structural investigations at the northwestern scarp of the Cenozoic Kilombero Rift allow the drawing of its structural evolution and establishment of stress conditions that prevailed at the different deformational episodes at this rift zone. The structure, where the northwestern scarp of the Cenozoic Kilombero Rift System is located, starts by ductile deformation of granitic and gabbroic rock masses leading to the formation gneissic fabric and b-mineral lineation in the rocks. This deformation is of Precambrian age (most probably a Pan African deformation) and its kinematics are characterized by 320˚/20˚ tectonic transport direction (λ1). Later the area was …

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Mechanistic Studies Of Carbon Steel Corrosion Inhibition By Cashew Nut Shell Liquid, J Y N Philip, J Buchweishaija, L L Mkayula Dec 2002

Mechanistic Studies Of Carbon Steel Corrosion Inhibition By Cashew Nut Shell Liquid, J Y N Philip, J Buchweishaija, L L Mkayula

Tanzania Journal of Science

The inhibition mechanism of the Cashew Nut Shell Liquid (CNSL) on SAE 1008 carbon steel corrosion in CO 2  saturated 3% NaCl solutions has been studied by weight loss, UV/VIS and electrochemical techniques. The phenoxide, R-Ar-O- ions from the CNSL inhibitor were found to be responsible for the reduction of the corrosion rate of the carbon steel. Also, it was observed that the surface charge of the carbon steel electrodes was positive with respect to the solutions containing CNSL inhibitor. It is likely that the mechanism of the CNSL inhibitor adsorption involved the electrostatic attraction between the positively charged metal …

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Preparation And Characterization Of Activated Carbons From Rice Husks And Shells Of Palm Fruits, Jeg Mdoe, Ll Mkayula Dec 2002

Preparation And Characterization Of Activated Carbons From Rice Husks And Shells Of Palm Fruits, Jeg Mdoe, Ll Mkayula

Tanzania Journal of Science

Activated carbons from palm fruit shells (PFS) and rice husks (RH) were prepared using physical and chemical activation processes, respectively. The influence of activation time and temperature (in the case of PFS) and impregnation ratio and carbonization temperature (in the case of RH) on the properties of the resultant carbons were studied. In the case of PFS carbons, there were an increase in adsorption capacity and surface areas with increase in activation time and temperature. The surface area ranged between 292 and 642 m2g-1 at temperature range of between 1000 and 1200 K. In the case of RH carbons, surface …

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Parts And Properties In Aristotle's Categories, Phil Corkum Dec 2002

Parts And Properties In Aristotle's Categories, Phil Corkum

The Society for Ancient Greek Philosophy Newsletter

Call a property recurrent if it can be found in more than one subject, and nonrecurrent otherwise. The question whether Aristotle holds that there are nonrecurrent properties has spawned a lively debate among recent commentators. An assumption held in common by both sides of the debate is that a property is nonrecurrent if it is inseparable from an individual subject. In this paper, I’ll argue that this assumption is false. There are a variety of kinds of separation in Aristotle. When we focus attention on what notion of separation is relevant, we will see that the inseparability possessed by individual …

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Perturbative Calculation Of The Triply Differential Cross Section For Photo-Double-Ionization Of He, Andrei Y. Istomin, N. L. Manakov, Anthony F. Starace Dec 2002

Perturbative Calculation Of The Triply Differential Cross Section For Photo-Double-Ionization Of He, Andrei Y. Istomin, N. L. Manakov, Anthony F. Starace

Anthony F. Starace Publications

Single-photon, two-electron ionization of He is analyzed, taking into account electron correlation using lowest-order perturbation theory and including all individual electron angular momenta in the final two-electron continuum. Perturbative account of electron correlation in the final state, which describes the so-called TS-1 mechanism of double photoionization, combined with a variational account of electron screening, is found to provide results for the triply differential cross section at an excess energy of 20 eV that are in excellent agreement with both absolute experimental data and results of non-perturbative calculations, for all kinematics of the process in which the TS-1 mechanism is expected …

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Hyperbolic Billiard Paths, Rebecca Lehman, Chad White Dec 2002

Hyperbolic Billiard Paths, Rebecca Lehman, Chad White

Mathematical Sciences Technical Reports (MSTR)

A useful way to investigate closed geodesics on a kaleidoscopically tiled surface is to look at the billiard path described by a closed geodesic on a single tile. When looking at billiard paths it is possible to ignore surfaces and restrict ourselves to the tiling of the hyperbolic plane. We classify the smallest billiard paths by wordlength and parity. We also demonstrate the existence of orientable paths and investigate conjectures about the billiard spectrum for the (2, 3, 7)-tiling.

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Pigeon-Holing Monodromy Groups, Niles G. Johnson Dec 2002

Pigeon-Holing Monodromy Groups, Niles G. Johnson

Mathematical Sciences Technical Reports (MSTR)

A simple tiling on a sphere can be used to construct a tiling on a d-fold branched cover of the sphere. By lifting a so-called equatorial tiling on the sphere, the lifted tiling is locally kaleidoscopic, yielding an attractive tiling on the surface. This construction is via a correspondence between loops around vertices on the sphere and paths across tiles on the cover. The branched cover and lifted tiling give rise to an associated monodromy group in the symmetric group on d symbols. This monodromy group provides a beautiful connection between the cover and its base space. Our investigation …

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The Weekly Challenger, December 26, 2002, The Weekly Challenger, Et Al Dec 2002

The Weekly Challenger, December 26, 2002, The Weekly Challenger, Et Al

Weekly Challenger Newspaper Collection

The December 26, 2002, issue of The Weekly Challenger.

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The Syntheses Of [Bzme3n]2[Mo4o10(Ome)6], Ridla Bakri Dec 2002

The Syntheses Of [Bzme3n]2[Mo4o10(Ome)6], Ridla Bakri

Makara Journal of Science

In an attempt to synthesize [BzMe3N]2Mo2O5(OMe)5 from the reaction of [BzMe3N]2MoO4 and MoO(OMe)4 in the ratio of 1:1 in methanol has produced [BzMe3N]2Mo4O10(OMe)6. The formation of [Mo4O10(OMe)6]2- anion suggests that ligand dissociation has occured in solution. Suitable crystals for X-ray chrystallographic were obtained from hot methanol and the crystal structure of [BzMe3N]2Mo4O10(OMe)6 has been solved and reported here in.

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The Syntheses Of [Bzme3n]2[Mo4o10(Ome)6], Ridla Bakri Dec 2002

The Syntheses Of [Bzme3n]2[Mo4o10(Ome)6], Ridla Bakri

Makara Journal of Science

In an attempt to synthesize [BzMe3N]2Mo2O5(OMe)5 from the reaction of [BzMe3N]2MoO4 and MoO(OMe)4 in the ratio of 1:1 in methanol has produced [BzMe3N]2Mo4O10(OMe)6. The formation of [Mo4O10(OMe)6]2- anion suggests that ligand dissociation has occured in solution. Suitable crystals for X-ray chrystallographic were obtained from hot methanol and the crystal structure of [BzMe3N]2Mo4O10(OMe)6 has been solved and reported here in.

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Reflection Influence On Output Frequency Spectrum At Submillimeter Frequency Tunable Gyrotrons, Aripin Aripin, B. Kurniawan Dec 2002

Reflection Influence On Output Frequency Spectrum At Submillimeter Frequency Tunable Gyrotrons, Aripin Aripin, B. Kurniawan

Makara Journal of Science

Influence of output window reflections on oscillatory processes in gyrotrons has been studied. The processes in a gyrotron have been modeled numerically, and enhancement of the spectrum signal in the presence of reflections has been studied. Dependencies of output power versus time and frequency spectrum for different value of reflection coefficient are given. Possibilities of significant increasing of output spectrum are demonstrated experimentally. The results demonstrate significant influence of reflections on operation stability and composition of the output radiation of the gyrotron.

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Reflection Influence On Output Frequency Spectrum At Submillimeter Frequency Tunable Gyrotrons, Aripin Aripin, B. Kurniawan Dec 2002

Reflection Influence On Output Frequency Spectrum At Submillimeter Frequency Tunable Gyrotrons, Aripin Aripin, B. Kurniawan

Makara Journal of Science

Influence of output window reflections on oscillatory processes in gyrotrons has been studied. The processes in a gyrotron have been modeled numerically, and enhancement of the spectrum signal in the presence of reflections has been studied. Dependencies of output power versus time and frequency spectrum for different value of reflection coefficient are given. Possibilities of significant increasing of output spectrum are demonstrated experimentally. The results demonstrate significant influence of reflections on operation stability and composition of the output radiation of the gyrotron.

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Search For The Production Of Single Sleptons Through R-Parity Violation In Pp̅ Collisions At √S = 1.8 Tev, V. M. Abazov, Gregory R. Snow, D0 Collaboration Dec 2002

Search For The Production Of Single Sleptons Through R-Parity Violation In Pp̅ Collisions At √S = 1.8 Tev, V. M. Abazov, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We report the first search for supersymmetric particles via s-channel production and decay of smuons or muon sneutrinos at hadronic colliders. The data for the two-muon and two-jets final states were collected by the D0 experiment and correspond to an integrated luminosity of 94 ± 5 pb-1. Assuming that R parity is violated via the single coupling λ′211, the number of candidate events is in agreement with expectation from the standard model. Exclusion contours are given in the (m0; m½) and (mΧ̅,mν planes for λ′ …

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