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Swelling Properties Of Coal Chars During Rapid Coal Pyrolysis And Combustion,, Thomas H. Fletcher Jan 1993

Swelling Properties Of Coal Chars During Rapid Coal Pyrolysis And Combustion,, Thomas H. Fletcher

Faculty Publications

Coal devolatilization experiments are commonly conducted at moderate temperatures (800 to 1300 K) and heating rates (103 to 104 Ks−1) in inert environments in order to measure evolved species before secondary reaction in the gas phase. However, chars from these experiments exhibit different physical characteristics than chars obtained under typical combustion conditions (1500 to 2000 K, 105 Ks−1, and 3 to 10 mol% oxygen). Experiments were conducted in two laminar, entrained-flow reactors to determine characteristics of coal chars in inert and oxygen-rich environments. One flow reactor was heated electrically, with gas temperatures of …

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Measurement Accuracy Of The Glottal Enterprises Pneumotachograph System, Christopher Dromey, Ronald C. Scherer, Chen-Geng Guo Jan 1993

Measurement Accuracy Of The Glottal Enterprises Pneumotachograph System, Christopher Dromey, Ronald C. Scherer, Chen-Geng Guo

Faculty Publications

No abstract provided.

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Aerodynamic And Acoustic Changes Following Intensive Voice Therapy For Patients With Parkinson's Disease: A Case Study, Christopher Dromey, Lorraine O. Ramig, Ronald Scherer Jan 1993

Aerodynamic And Acoustic Changes Following Intensive Voice Therapy For Patients With Parkinson's Disease: A Case Study, Christopher Dromey, Lorraine O. Ramig, Ronald Scherer

Faculty Publications

No abstract provided.

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Radiative Lifetimes, Branching Ratios, And Absolute Transition Probabilities In Cr Ii And Zn Ii, Scott D. Bergeson, J. E. Lawler Jan 1993

Radiative Lifetimes, Branching Ratios, And Absolute Transition Probabilities In Cr Ii And Zn Ii, Scott D. Bergeson, J. E. Lawler

Faculty Publications

New absolute atomic transition probability measurements are reported for 12 transitions in Cr II and two transitions in Zn II. These transition probabilities are determined by combining branching ratios measured by classical techniques and radiative lifetimes measured by time-resolved laser-induced fluorescence. The measurements are compared with branching fractions, radiative lifetimes, and transition probabilities in the literature. The 206 nm resonance multiplets in Cr II and Zn II are included in this work. These multiplets are very useful in determining the distribution of the elements in the gas versus grain phases in the interstellar medium.

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Oscillator Strengths Of The Si Ii 181 Nanometer Resonance Multiplet, Scott D. Bergeson, J. E. Lawler Jan 1993

Oscillator Strengths Of The Si Ii 181 Nanometer Resonance Multiplet, Scott D. Bergeson, J. E. Lawler

Faculty Publications

We report Si II experimental log (gf)-values of –2.38(4) for the 180.801 nm line, of –2.18(4) for the 181.693 nm line, and of –3.29(5) for the 181.745 nm line, where the number in parenthesis is the uncertainty in the last digit. The overall uncertainties (~10%) include the 1 σ random uncertainty (~6%) and an estimate of the systematic uncertainty. The oscillator strengths are determined by combining branching fractions and radiative lifetimes. The branching fractions are measured using standard spectroradiometry on an optically thin source; the radiative lifetimes are measured using time-resolved laser-induced fluorescence.

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Ti-Ii Transition Probabilities And Radiative Lifetimes In Ti+ And The Solar Titanium Abundance, A. Bizzarri, M.C.E. Huber, A. Noels, N. Grevesse, Scott D. Bergeson, P. Tsekeris, J. E. Lawler Jan 1993

Ti-Ii Transition Probabilities And Radiative Lifetimes In Ti+ And The Solar Titanium Abundance, A. Bizzarri, M.C.E. Huber, A. Noels, N. Grevesse, Scott D. Bergeson, P. Tsekeris, J. E. Lawler

Faculty Publications

Transition probabilities of 100 Ti-II emission lines, originating from 7 different atomic levels, have been determined by combining branching fractions with radiative lifetimes. The branching fractions were meaures using Fourier transform spectroscopy on a hollow cathode. The radiative lifetimes of these 7 – and 35 additional – levels were measured using time resolved laser-induced fluorescence on a slow Ti ion beam. The transition probabilities of 21 very weak lines have been used to derive a solar titanium abundance of aTi=log(NTi/NH)+12=5.04±0.04 dex, which is insensitive to the solar model. This value is in …

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Transition Probabilities For The 3s23p(2PO)–3s3p2(4P) Intersystem Lines Of Si Ii, Anthony G. Calamai, Peter L. Smith, Scott D. Bergeson Jan 1993

Transition Probabilities For The 3s23p(2PO)–3s3p2(4P) Intersystem Lines Of Si Ii, Anthony G. Calamai, Peter L. Smith, Scott D. Bergeson

Faculty Publications

Intensity ratios of lines of the spin-changing "intersystem" multiplet of Si II (4P → 2Po) at 234 nm have been used to determine electron densities and temperatures in a variety of astrophysical environments. However, the accuracy of these diagnostic calculations have been limited by uncertainties associated with the available atomic data. We report the first laboratory measurement, using an ion-trapping technique, of the radiative lifetimes of the three metastable levels of the 3s3p2 4P term of Si II. Our results are 104 ± 16, 406 ± 33, and 811 ± 77 µs for …

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An Overview Of Acerc Research In Fuel Characterization And Reaction Mechanisms, Ronald J. Pugmire, Thomas H. Fletcher Jan 1993

An Overview Of Acerc Research In Fuel Characterization And Reaction Mechanisms, Ronald J. Pugmire, Thomas H. Fletcher

Faculty Publications

A major objective of the Advanced Combustion Engineering Research Center is the development and verification of data on fuel characterization and reaction mechanisms and rates that can be incorporated into submodels for use in the comprehensive combustion codes. As technology has advanced, the levels of analytical sophistication has also advanced, making it possible to augment the existing body of information with new data. From this new data it is possible to draw new insights regarding the complex nature of coal and the various processes associated with combustion. The ACERC program has made it possible to bring different disciplines together to …

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Chemical Structural Features Of Pyridine Extracts Of The Argonne Premium Coals Using 13c Nmr Spectroscopy, Thomas H. Fletcher, S Bai, Ronald J. Pugmire, Steven Wood, David M. Grant Jan 1993

Chemical Structural Features Of Pyridine Extracts Of The Argonne Premium Coals Using 13c Nmr Spectroscopy, Thomas H. Fletcher, S Bai, Ronald J. Pugmire, Steven Wood, David M. Grant

Faculty Publications

Soxhlet extractions were performed on the eight Argonne Premium coals using pyridine purged with argon and followed by a novel washing procedure to remove the pyridine. Mass closure (extracts plus residues) on duplicate experiments accounted for 94-96% of the original coal, repeatable to within 2%. Chemical structural features determined from 13C NMR analyses of the extracts and residues showed more attachments per aromatic cluster for the residues, indicating a greater degree of covalent bonding in the residue than in the extract. 1H NMR analysis of the extracts showed a gradual increase in the hydrogen aromaticity with rank, along …

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Plasma Total Glutathione In Humans And Its Association With Demographic And Health-Related Factors, Elaine W. Flagg, Ralph J. Coates, J. William Eley, Raymond S. Greenberg, Dean P. P. Jones, Elaine W. Gunter, Bethany Jackson Jan 1993

Plasma Total Glutathione In Humans And Its Association With Demographic And Health-Related Factors, Elaine W. Flagg, Ralph J. Coates, J. William Eley, Raymond S. Greenberg, Dean P. P. Jones, Elaine W. Gunter, Bethany Jackson

Faculty Publications

The tripeptide glutathione is proposed to be protective against a number of chronic diseases including cardiovascular disease and cancer. However, there have been few studies of plasma glutathione levels in humans and in those studies the numbers of participants have been very small. In an exploratory analysis the determinants of plasma total glutathione (GSHt) were investigated in a group of 100 volunteers aged 18–61 years in Atlanta, Georgia, USA during June and July 1989. Data on demographic and health-related factors were collected by interview and plasma GSHt was measured using a recently modified laboratory method. The mean concentration of plasma …

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Effects Of Aerobic Training In Adolescents With Down Syndrome, A. Lynn Millar, Bo Fernhall, Lee N. Burkett Jan 1993

Effects Of Aerobic Training In Adolescents With Down Syndrome, A. Lynn Millar, Bo Fernhall, Lee N. Burkett

Faculty Publications

The purpose of this study was to evaluate the effects that aerobic training has on adolescents and young adults with Down syndrome. Fourteen individuals with Down syndrome (mean age = 17.7 yr) participated in a 10-wk walking/jogging exercise training study. A pre- and post-training walking treadmill test was performed to determine the following parameters: peak oxygen uptake (VO2, absolute and relative), minute ventilation (VE, l•min-1), heart rate HR, b•min-1), RER (VCO2/VO2), and time and grade to exhaustion. Following the pre-training evaluations, subjects were assigned to a control group (N = 4) or an exercise group (N= 10). The exercise group …

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The Fluidity Of Tribal Peoples In Central Transjordan : Four Millennia Of Sedentarization And Nomadization On The Madaba Plains, Oystein S. Labianca Jan 1993

The Fluidity Of Tribal Peoples In Central Transjordan : Four Millennia Of Sedentarization And Nomadization On The Madaba Plains, Oystein S. Labianca

Faculty Publications

No abstract provided.

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Observation Of Hard Scattering In Photoproduction At Hera, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, J. Repond, K. Sugano, R. Stanek, R. L. Talaga, J. Thron, F. Arzarello, R. Ayed, G. Barbagli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, M. Chiarini, L. Cifarelli, F. Cindolo, F. Ciralli, A. Contin, S. D'Auria, C. Del Papa, F. Frasconi, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, Q. Lin Dec 1992

Observation Of Hard Scattering In Photoproduction At Hera, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, J. Repond, K. Sugano, R. Stanek, R. L. Talaga, J. Thron, F. Arzarello, R. Ayed, G. Barbagli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, G. Bruni, P. Bruni, G. Cara Romeo, G. Castellini, M. Chiarini, L. Cifarelli, F. Cindolo, F. Ciralli, A. Contin, S. D'Auria, C. Del Papa, F. Frasconi, P. Giusti, G. Iacobucci, G. Laurenti, G. Levi, Q. Lin

Faculty Publications

We report a study of electron proton collisions at very low Q2, corresponding to virtual photoproduction at centre of mass energies in the range 100-295 GeV. The distribution in transverse energy of the observed hadrons is much harder than can be explained by soft processes. Some of the events show back-to-back two-jet production at the rate and with the characteristics expected from hard two-body scattering. A subset of the two-jet events have energy in the electron direction consistent with that expected from the photon remnant in resolved photon processes. © 1992.

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Denitrification And Oxygen Consumption In Sediments Of Two South Texas Estuaries, Won Bae Yoon, Ronald Benner Dec 1992

Denitrification And Oxygen Consumption In Sediments Of Two South Texas Estuaries, Won Bae Yoon, Ronald Benner

Faculty Publications

Spatial and temporal variations in rates of denitrification and oxygen consumption were measured in sediments of the Nueces and Guadalupe Estuaries in southern Texas, USA. Denitrification rates varied from 4.0 to 71.1 µmol N2 m-2 h-1 in the Nueces Estuary and from 4.6 to 34.7 µmol N2 m-2 h-1 in the Guadalupe Estuary. Denitrification accounted for 29 to 80% of total benthic N flux in the study areas. Oxygen consumption rates ranged from 176 to 818 µmol O2 m-2 h-1 in Nueces Estuary and from 208 to 550 µmol O2 …

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Bacterial Numbers And Activity, Microalgal Biomass And Productivity, And Meiofaunal Distribution In Sediments Naturally Contaminated With Biogenic Bromophenols, Charles C. Steward, James L. Pinckney, Yvette Piceno, Charles R. Lovell Dec 1992

Bacterial Numbers And Activity, Microalgal Biomass And Productivity, And Meiofaunal Distribution In Sediments Naturally Contaminated With Biogenic Bromophenols, Charles C. Steward, James L. Pinckney, Yvette Piceno, Charles R. Lovell

Faculty Publications

Sediment cores were collected inside and outside of a bed of a bromophenol-producing marine polychaete, Notomastus lobatus, and examined for impact of the bromophenols on sediment microflora and meiofauna around N. lobatus burrows. No significant differences were found between microbial parameters measured inside and outside of the N. lobatus bed. Integrated 6 cm cores taken adjacent to N. lobatus burrows contained 1.2 x 109 bacteria ml-1. Cell numbers were similar at control sites within the bed, but away from burrows, and not significantly different from cell numbers (1.0 X 109 cells ml-1) at a …

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Structural Evidence For Nonplanar Keto- And Planar Enol-Forms Of Oxophlorins, Mathias O. Senge, Kevin M. Smith Dec 1992

Structural Evidence For Nonplanar Keto- And Planar Enol-Forms Of Oxophlorins, Mathias O. Senge, Kevin M. Smith

Faculty Publications

The first structural investigation of a zinc(II) and a free-base oxophlorin reveals considerable conformational differences between the keto- (1) and enol-form (2) of oxophlorins.

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Inhomogeneous Boundary Effects In Semiconductor Quantum Wires, G. Y. Hu, R. F. O'Connell Dec 1992

Inhomogeneous Boundary Effects In Semiconductor Quantum Wires, G. Y. Hu, R. F. O'Connell

Faculty Publications

Boundary effects play an essential role in determining the physical properties of semiconductor quantum wires. Additional features come into play when one considers inhomogeneous boundaries, i.e. wires whose widths are functions of distance along the length of the wire. The authors show that, in the adiabatic approximation (which assumes that the boundary potential fluctuation effects, or equivalently, the variations in the wire width, occur on a scale much larger than the inverse of Fermi wavelength), the boundary problem for a quantum wire is equivalent to a one-dimensional Schrodinger equation along the wire with: (i) an effective potential provided by the …

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An Inservice Model To Impact Life Science Classroom Practice: Part One, David P. Butts, Wyatt Anderson, Mary Atwater, Thomas Koballa, Patricia Simmons, Rosalina Hairston Dec 1992

An Inservice Model To Impact Life Science Classroom Practice: Part One, David P. Butts, Wyatt Anderson, Mary Atwater, Thomas Koballa, Patricia Simmons, Rosalina Hairston

Faculty Publications

A model inservice program built on a theoretical foundation for changing behavior incorporates both teachers' knowledge, their attitudes as well as what they do. What teachers do in the classroom depends on both what they know and how they feel about what they know, Changing what teachers know and do is accomplished in a three phase sequence, awareness, arousal and action. In the awareness phase, teachers are confronted with their knowledge needs. In the arousal phase, teacher generate interest in using what they know. Action is reflected in what teachers do and is reinforced when they have time to reflect …

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The Making Of Social Policy In Britain 1830-1990, L. Margaret Barnett Dec 1992

The Making Of Social Policy In Britain 1830-1990, L. Margaret Barnett

Faculty Publications

No abstract provided.

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Diffraction Properties Of Stratified Volume Holographic Optical Elements, Gregory P. Nordin, R. V. Johnson, A. R. Tanguay Dec 1992

Diffraction Properties Of Stratified Volume Holographic Optical Elements, Gregory P. Nordin, R. V. Johnson, A. R. Tanguay

Faculty Publications

We present a unified treatment of the diffraction properties of stratified volume holographic optical elements (SVHOE's). We show that the relative phasing of the diffraction orders as they propagate from layer to layer gives rise to a unique notched diffraction response of the +1 order (for the case of Bragg incidence) as a function of the normalized buffer-layer thickness, the grating spatial frequency, and the readout wavelength. For certain combinations of these parameters Bragg diffraction behavior characteristic of volume holographic optical elements (VHOE's) is observed, whereas for other combinations pure Raman-Nath behavior periodically recurs. By using these same relative-phasing arguments, …

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Photopolymer-Based Stratified Volume Holographic Optical Elements, Gregory P. Nordin, A. R. Tanguay Dec 1992

Photopolymer-Based Stratified Volume Holographic Optical Elements, Gregory P. Nordin, A. R. Tanguay

Faculty Publications

We report the implementation of stratified volume holographic optical elements (SVHOE's) using DuPont's Omnidex holographic photopolymer material and an in situ exposure technique for simultaneous multilayer grating recording. Experimental measurement of the +1-order angular sensitivity of a seven-layer SVHOE structure shows remarkable agreement with both theory and numerical simulation for incidence angles near the Bragg angle. For SVHOE's having modulation layers that individually operate in the Bragg or transition diffraction regimes, the envelope of the SVHOE angular sensitivity is experimentally shown to approximate closely that of a single modulation layer.

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Conventionalism And Contractarianism, Noel B. Reynolds Nov 1992

Conventionalism And Contractarianism, Noel B. Reynolds

Faculty Publications

In this paper Noel B. Reynolds’s theory of law as convention is compared to the public choice contractarian theory of James M. Buchanan. While there are numerous similarities, major differences emerge. Only conventionalism can produce legal and political authority and norms to guide the use of that authority in maintaining the rule of law. The concept of constructive unanimity is introduced to overcome the ultimate failure of contractarianism to legitimate the authority of law.

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Tutte Polynomials Computable In Polynomial Time, J. G. Oxley, D. J.A. Welsh Nov 1992

Tutte Polynomials Computable In Polynomial Time, J. G. Oxley, D. J.A. Welsh

Faculty Publications

We show that for any accessible class of matroids of bounded width, the Tutte polynomial is computable in polynomial time. © 1992.

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S Corporation Current Developments, Annette M. Nellen, S. S. Karlinsky Nov 1992

S Corporation Current Developments, Annette M. Nellen, S. S. Karlinsky

Faculty Publications

No abstract provided.

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Labeling Graphs With A Condition At Distance 2, Jerrold R. Griggs, Roger K. Yeh Nov 1992

Labeling Graphs With A Condition At Distance 2, Jerrold R. Griggs, Roger K. Yeh

Faculty Publications

No abstract provided.

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Correlates To Performance On Field Tests Of Muscular Strength, Jeffrey A. Woods, Russell R. Pate, Maria L. Burgess Nov 1992

Correlates To Performance On Field Tests Of Muscular Strength, Jeffrey A. Woods, Russell R. Pate, Maria L. Burgess

Faculty Publications

Field tests of upper body muscular strength and endurance (UBMSE) are often administered to children, but little is known about the determinants of performance on these tests. Therefore the purpose of this investigation was to examine potential determinants of performance on several common field tests of UBMSE including pull-ups, flexed-arm hang, push-ups, and two types of modified pull-ups. Subjects were 56 girls, and 38 boys, ages 9 to 11 years. Potential determinants assessed were age, height, weight, gender, % fat, physical activity, and laboratory measures of muscular strength and endurance. Multiple regression analysis revealed that the laboratory measures of UBMSE …

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Unobserved Ability, Efficiency Wages, And Interindustry Wage Differentials, Mckinley L. Blackburn, David Neumark Nov 1992

Unobserved Ability, Efficiency Wages, And Interindustry Wage Differentials, Mckinley L. Blackburn, David Neumark

Faculty Publications

One competitive-market explanation of interindustry wage differentials that is not challenged by the persistence of these differentials is that they are due to differences across workers in unobserved ability or quality. In contrast, this paper explores the unobserved ability hypothesis by using test scores as error-ridden indicators of ability, and family background variables as instruments.This approach avoids two potential problems with using first-difference methods to remove omitted-ability bias from wage equation estimates of industry effects the exacerbation of measurement error from misclassification of industry, and selectivity with respect to industry changes. However, this approach may introduce other problems, for two …

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When Blood Won't Clot, Debra Ann Mills Nov 1992

When Blood Won't Clot, Debra Ann Mills

Faculty Publications

While the history books refer to hemophilia as the disease of kings because it was once common among European royalty, the disorder now makes headlines for a completely different reason. It is estimated that at least 70% of the hemophiliacs whoo received blood products between 1978 and 1985 have been infected with HIV.

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Doping Out The Capitalization Rules After Indopco, John W. Lee Nov 1992

Doping Out The Capitalization Rules After Indopco, John W. Lee

Faculty Publications

In this article, Lee provides guidance for Treasury and the IRS (in their promised clarification of application of INDOPCO). He delineates how to avoid what he perceives as the past pitfalls of capitalization of recurring, insubstantial, or relatively short-lived expenditures with Ito, or inadequate, amortization. The article also sets forth models for (a) amortizing as. a freestanding deferred charge long-lived substantial self-created intangibles such as business expansion costs, including employee training costs, and (b) expensing, or perhaps better, amortizing currently less substantial or regularly recurring, steady state self-created intangibles (such as repairs and advertising, respectively).

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Linear Theory Of Non-Neutral Plasma Equilibrium In A Tilted Magnetic Field, Ross L. Spencer, Grant W. Hart Nov 1992

Linear Theory Of Non-Neutral Plasma Equilibrium In A Tilted Magnetic Field, Ross L. Spencer, Grant W. Hart

Faculty Publications

A linear perturbation expansion has been found that allows the rapid and accurate calculation of the response of a non-neutral plasma to a tilted magnetic field. The results of the calculation have been found to agree with previous three-dimensional equilibrium calculations, and also to agree with Keinigs' [Phys. Fluids 24, 860 (1981)] calculation of zero-frequency resonances caused by magnetic field errors. This expansion also allows the perturbed velocity to be calculated. It is speculated that this perturbed flow may be related to the enhanced radial transport in a non-neutral plasma with a tilted magnetic field.

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