Friday, May 13, 2011

100 Sustainability Articles




The following is a sample of 100 sustainability related publications by investigators at Georgia Tech over the last 5 years (2006-2010) spanning a range of topics including transportation, buildings, energy, environment, metrics, curriculum, decision making, philosophy, climate, natural resources, economics, design, policy, and manufacturing.




  1. Best Practices and Common Approaches for Considering Sustainability at US State Transportation Agencies; Barrella E, Amekudzi AA, Meyer MD, et al.; TRANSPORTATION RESEARCH RECORD; No. 2174; pp 10-18; 2010.

  2. Switchgrass as an energy crop for biofuel production: A review of its ligno-cellulosic chemical properties; David K, Ragauskas AJ; ENERGY & ENVIRONMENTAL SCIENCE; V3 No. 9; pp 1182-1190; SEP 2010.

  3. Point-based standard optimization with life cycle assessment for product design; Lu D, Realff MJ; COMPUTERS & CHEMICAL ENGINEERING; V34 No. 9; pp 1356-1364; SEP 7 2010.

  4. Gigaton Problems Need Gigaton Solutions ; Xu M, Crittenden JC, Chen YS, et al.; ENVIRONMENTAL SCIENCE & TECHNOLOGY; V44 No. 11; pp. 4037-4041; JUN 1 2010.

  5. Evolution of the Transition to a World Driven by Renewable Energy; Fronk BM, Neal R, Garimella S; JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME; V132 No. 2 Article Number: 021009; JUN 2010.

  6. Optimal decision making on urban renewal projects; Juan YK, Roper KO, Castro-Lacouture D, et al.; MANAGEMENT DECISION; V48 No. 1-2; pp 207-224; 2010.

  7. Foundations of Environmental Sustainability: The Co-evolution of Science and Policy; Norton BG; ORGANIZATION & ENVIRONMENT; V23 No. 1; pp 103-106; MAR 2010.

  8. Evaluating Plan Alternatives for Transportation System Sustainability: Atlanta Metropolitan Region; Jeon CM, Amekudzi AA, Guensler RL; INTERNATIONAL JOURNAL OF SUSTAINABLE TRANSPORTATION; V4 No. 4; pp 227-247; 2010.

  9. The forest products industry at an energy/climate crossroads; Brown MA, Baek Y; ENERGY POLICY; V38 No. 12; pp. 7665-7675; DEC 2010.

  10. Life Cycle Energy and Greenhouse Gas Emissions for an Ethanol Production Process Based on Blue-Green Algae; Luo DX, Hu ZS, Choi DG, et al.; ENVIRONMENTAL SCIENCE & TECHNOLOGY; V44 No. 22; pp. 8670-8677; NOV 15 2010.

  11. Statehouse Versus Greenhouse; Drummond WJ; JOURNAL OF THE AMERICAN PLANNING ASSOCIATION; V76 No. 4; pp. 413-433; 2010.

  12. Maximizing efficiency in the transition to a coal-based economy; Brathwaite J, Horst S, Iacobucci J; ENERGY POLICY; V38 No. 10; pp. 6084-6091; OCT 2010.

  13. A Biologically-Inspired Micro Aerial Vehicle; Ratti J, Vachtsevanos G; JOURNAL OF INTELLIGENT & ROBOTIC SYSTEMS; V60 No. 1; pp. 153-178; OCT 2010.

  14. Energy Implications of Product Leasing; Intlekofer K, Bras B, Ferguson M; ENVIRONMENTAL SCIENCE & TECHNOLOGY; V44 No. 12; pp. 4409-4415; JUN 15 2010.

  15. Harvesting Waste Thermal Energy Using Carbon-Nanotube-Based Thermo-Electrochemical Cell; Hu RC, Cola BA, Haram N, et al.; NANO LETTERS; V10 No. 3; pp. 838-846; MAR 2010.

  16. Using Aerial Imagery and GIS in Automated Building Footprint Extraction and Shape Recognition for Earthquake Risk Assessment of Urban Inventories; Sahar L, Muthukumar S, French SP; IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING; V48 No. 9; pp. 3511-3520; SEP 2010.

  17. Urban Form and Extreme Heat Events: Are Sprawling Cities More Vulnerable to Climate Change Than Compact Cities?; Stone B, Hess JJ, Frumkin H; ENVIRONMENTAL HEALTH PERSPECTIVES; V118 No. 10; pp. 1425-1428; OCT 2010.

  18. Biomass burning impact on PM2.5 over the southeastern US during 2007: integrating chemically speciated FRM filter measurements, MODIS fire counts and PMF analysis; Zhang X, Hecobian A, Zheng M, et al.; ATMOSPHERIC CHEMISTRY AND PHYSICS; V10 No. 14; pp. 6839-6853; 2010.

  19. Urban and Regional Policy and Its Effects, vol 1; Schaffer WA; JOURNAL OF THE AMERICAN PLANNING ASSOCIATION; V76 No. 2; pp. 257-258; 2010.

  20. Spatial Dependence and Divergence across Chinese Cities; Ho CY, Li D; REVIEW OF DEVELOPMENT ECONOMICS; V14 No. 2; pp. 386-403; MAY 2010.

  21. Cost Analysis of Impacts of Climate Change on Regional Air Quality; Liao KJ, Tagaris E, Russell AG, et al.; JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION; V60 No. 2; pp. 195-203; FEB 2010.

  22. Cellulosic biorefineries-unleashing lignin opportunities; Sannigrahi P, Pu YQ, Ragauskas A; CURRENT OPINION IN ENVIRONMENTAL SUSTAINABILITY; V2 No. 5-6; pp. 383-393; DEC 2010.

  23. Designing for a Green Future: A Unified Aircraft Design Methodology; Kernstine K, Boling B, Bortner L, et al.; JOURNAL OF AIRCRAFT; V47 No. 5; pp. 1789-1797; SEP-OCT 2010.

  24. An empirical investigation of environmental performance and the market value of the firm; Jacobs BW, Singhal VR, Subramanian R; JOURNAL OF OPERATIONS MANAGEMENT; V28 No. 5; pp. 430-441; SEP 2010.

  25. A Framework for Portfolio Management of Renewable Hybrid Energy Sources; Ender TR, Murphy J, Haynes CL; IEEE SYSTEMS JOURNAL; V4 No. 3; pp. 295-302; SEP 2010.

  26. Poplar as a feedstock for biofuels: A review of compositional characteristics; Sannigrahi P, Ragauskas AJ, Tuskan GA; BIOFUELS BIOPRODUCTS & BIOREFINING-BIOFPR; V4 No. 2; pp. 209-226; MAR-APR 2010.

  27. Greenhouse Gas and Climate Change Assessment; Meyer MD; JOURNAL OF THE AMERICAN PLANNING ASSOCIATION; V76 No. 4; pp. 402-412; 2010.

  28. Power Flow Control in Networks Using Controllable Network Transformers; Das D, Divan DM, Harley RG; IEEE TRANSACTIONS ON POWER ELECTRONICS; V25 No. 7; pp. 1753-1760; JUL 2010.

  29. EXTENDED-RANGE PROBABILISTIC FORECASTS OF GANGES AND BRAHMAPUTRA FLOODS IN BANGLADESH; Webster PJ, Jian J, Hopson TM, et al.; BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY; V91 No. 11; pp. 1493-U121; NOV 2010.

  30. Constructing Carbon Market Spacetime: Climate Change and the Onset of Neo-Modernity; Knox-Hayes J; ANNALS OF THE ASSOCIATION OF AMERICAN GEOGRAPHERS; V100 No. 4; pp. 953-962; 2010.

  31. Coral records of central tropical Pacific radiocarbon variability during the last millennium; Zaunbrecher LK, Cobb KM, Beck JW, et al.; PALEOCEANOGRAPHY; V25 Article Number: PA4212; NOV 10 2010.

  32. Extended-range seasonal hurricane forecasts for the North Atlantic with a hybrid dynamical-statistical model; Kim HM, Webster PJ; GEOPHYSICAL RESEARCH LETTERS; V37 Article Number: L21705; NOV 9 2010.

  33. Resilient Cities: Responding to Peak Oil and Climate Change; Elliott M; JOURNAL OF URBAN TECHNOLOGY; V17 No. 2; pp. 121-123; 2010.

  34. Accelerated warming of the Southern Ocean and its impacts on the hydrological cycle and sea ice; Liu JP, Curry JA; PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA; V107 No. 34; pp. 14987-14992; AUG 24 2010.

  35. Corals in Crisis; Hay ME, Rasher DB; SCIENTIST; V24 No. 8; pp. 42-46; AUG 2010.

  36. Sensitivity of Air Pollution-Induced Premature Mortality to Precursor Emissions under the Influence of Climate Change; Tagaris E, Liao KJ, DeLucia AJ, et al.; INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH; V7 No. 5; pp. 2222-2237; MAY 2010.

  37. How To Cool the Planet: Geoengineering and the Audacious Quest To Fix the Earth's Climate; Baer W; LIBRARY JOURNAL; V135 No. 6; pp. 92-92; APR 1 2010.

  38. GA-based decision support system for housing condition assessment and refurbishment strategies; Juan YK, Kim JH, Roper K, et al.; AUTOMATION IN CONSTRUCTION; V18 No. 4; pp 394-401; JUL 2009.

  39. Design, demonstrations and sustainability impact assessments for plug-in hybrid electric vehicles ; Bradley TH, Frank AA; RENEWABLE & SUSTAINABLE ENERGY REVIEWS; V13 No. 1; pp 104-117; JAN 2009.

  40. Comparison of Design Methods for Fuel-Cell-Powered Unmanned Aerial Vehicles; Bradley TH, Moffitt BA, Fuller TF, et al.; JOURNAL OF AIRCRAFT; V46 No. 6; pp. 1945-1956; NOV-DEC 2009.

  41. Critical Interfaces in Organic Solar Cells and Their Influence on the Open-Circuit Voltage; Potscavage WJ, Sharma A, Kippelen B; ACCOUNTS OF CHEMICAL RESEARCH; V42 No. 11; pp. 1758-1767; NOV 2009.

  42. Trendy solutions: Why do states adopt Sustainable Energy Portfolio Standards?; Chandler J; ENERGY POLICY; V37 No. 8; pp. 3274-3281; AUG 2009.

  43. Performance of Li-ion secondary batteries in low power, hybrid power supplies; Prakash S, Mustain WE, Kohl PA; JOURNAL OF POWER SOURCES; V189 No. 2; pp. 1184-1189; APR 15 2009.

  44. Growing Cooler: The Evidence on Urban Development and Climate Change.; Brown MA; REVIEW OF POLICY RESEARCH; V26 No. 1-2; pp. 228-231; JAN-MAR 2009.

  45. Land Use as Climate Change Mitigation; Stone B; ENVIRONMENTAL SCIENCE & TECHNOLOGY; V43 No. 24; pp. 9052-9056; DEC 15 2009.

  46. Global Universities and Urban Development: Case Studies and Analysis; Etienne HF; ECONOMIC DEVELOPMENT QUARTERLY; V23 No. 3; pp. 267-267; AUG 2009.

  47. Roadside, Urban, and Rural Comparison of Primary and Secondary Organic Molecular Markers in Ambient PM2.5; Yan B, Zheng M, Hu YT, et al.; ENVIRONMENTAL SCIENCE & TECHNOLOGY; V43 No. 12; pp. 4287-4293; JUN 15 2009.

  48. Socio-demographic and built environment influences on the odds of being overweight or obese: The Atlanta experience; Bodea TD, Garrow LA, Meyer MD, et al.; TRANSPORTATION RESEARCH PART A-POLICY AND PRACTICE; V43 No. 4; pp. 430-444; MAY 2009.

  49. At Home in the Seamless Web Agency, Obduracy, and the Ethics of Metropolitan Growth; Kirkman R; SCIENCE TECHNOLOGY & HUMAN VALUES; V34 No. 2; pp. 234-258; MAR 2009.

  50. Quantification of the impact of climate uncertainty on regional air quality; Liao KJ, Tagaris E, Manomaiphiboon K, et al.; ATMOSPHERIC CHEMISTRY AND PHYSICS; V9 No. 3; pp. 865-878; 2009.

  51. Assessment of Biomass Burning Emissions and Their Impacts on Urban and Regional PM2.5: A Georgia Case Study; Tian D, Hu YT, Wang YH, et al.; ENVIRONMENTAL SCIENCE & TECHNOLOGY; V43 No. 2; pp. 299-305; JAN 15 2009.

  52. Efficient Take-Back Legislation; Atasu A, Van Wassenhove LN, Sarvary M; PRODUCTION AND OPERATIONS MANAGEMENT; V18 No. 3; pp. 243-258; MAY-JUN 2009.

  53. The Greenhouse Development Rights Framework: Drawing Attention to Inequality within Nations in the Global Climate Policy Debate; Baer P, Kartha S, Athanasiou T, et al.; DEVELOPMENT AND CHANGE; V40 No. 6; pp. 1121-1138; NOV 2009.

  54. Relation of biofuel to bioelectricity and agriculture: Food security, fuel security, and reducing greenhouse emissions; Thomas VM, Choi DG, Luo D, et al.; CHEMICAL ENGINEERING RESEARCH & DESIGN; V87 No. 9A Special No. Sp. Iss. SI; pp. 1140-1146; SEP 2009.

  55. Late 20th century warming and freshening in the central tropical Pacific; Nurhati IS, Cobb KM, Charles CD, et al.; GEOPHYSICAL RESEARCH LETTERS; V36 Article Number: L21606; NOV 12 2009.

  56. Adsorbent Materials for Carbon Dioxide Capture from Large Anthropogenic Point Sources; Choi S, Drese JH, Jones CW; CHEMSUSCHEM; V2 No. 9; pp. 796-854; 2009.

  57. The Value of Quality Grading in Remanufacturing; Ferguson M, Guide VD, Koca E, et al.; PRODUCTION AND OPERATIONS MANAGEMENT; V18 No. 3; pp. 300-314; MAY-JUN 2009.

  58. AEC plus P plus F INTEGRATION WITH GREEN PROJECT DELIVERY AND LEAN FOCUS; Castro-Lacouture D, Ospina-Alvarado AM, Roper KO; JOURNAL OF GREEN BUILDINGV3 No. 4; pp 154-169; FALL 2008.

  59. Comparative assessment of lunar propellant options; Stanley DO, Martinez RM; JOURNAL OF SPACECRAFT AND ROCKETS; V45 No. 4; pp 776-784; JUL-AUG 2008.

  60. Extending Amdahl's Law for Energy-Efficient Computing in the Many-Core Era; Woo DH, Lee HHS; COMPUTER; V41 No. 12; pp. 24-+; DEC 2008.

  61. Simulations of absorbance efficiency and power production of three dimensional tower arrays for use in photovoltaics; Flicker J, Ready J; JOURNAL OF APPLIED PHYSICS; V103 No. 11 Article Number: 113110; JUN 1 2008.

  62. A survey of unresolved problems in life cycle assessment; Reap J, Roman F, Duncan S, et al.; INTERNATIONAL JOURNAL OF LIFE CYCLE ASSESSMENT; V13 No. 5; pp. 374-388; AUG 2008.

  63. The connectivity of streets: reach and directional distance; Peponis J, Bafna S, Zhang ZY; ENVIRONMENT AND PLANNING B-PLANNING & DESIGN; V35 No. 5; pp. 881-901; SEP 2008.

  64. The Future of GIS in Planning: Converging Technologies and Diverging Interests; Drummond WJ, French SP; JOURNAL OF THE AMERICAN PLANNING ASSOCIATION; V74 No. 2; pp. 161-174; 2008.

  65. Optimization of community health center locations and service offerings with statistical need estimation; Griffin PM, Scherrer CR, Swann JL; IIE TRANSACTIONS; V40 No. 9; pp. 880-892; 2008.

  66. Development of ambient air quality population-weighted metrics for use in time-series health studies; Ivy D, Mulholland JA, Russell AG; JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION; V58 No. 5; pp. 711-720; MAY 2008.

  67. Simulation of air quality impacts from prescribed fires on an urban area; Hu YT, Odman MT, Chang ME, et al.; ENVIRONMENTAL SCIENCE & TECHNOLOGY; V42 No. 10; pp. 3676-3682; MAY 15 2008.

  68. Choices versus choice sets: a commuting spectrum method for representing job-housing possibilities; Yang JW, Ferreira J; ENVIRONMENT AND PLANNING B-PLANNING & DESIGN; V35 No. 2; pp. 364-378; MAR 2008.

  69. Understanding the inputs into innovation: Do cities substitute for internal firm resources?; Forman C, Goldfarb A, Greenstein S; JOURNAL OF ECONOMICS & MANAGEMENT STRATEGY; V17 No. 2; pp. 295-316; SUM 2008.

  70. Diagnosis of aged prescribed burning plumes impacting an urban area; Lee S, Kim HK, Yan B, et al.; ENVIRONMENTAL SCIENCE & TECHNOLOGY; V42 No. 5; pp. 1438-1444; MAR 1 2008.

  71. Remanufacturing as a Marketing Strategy; Atasu A, Sarvary M, Van Wassenhove LN; MANAGEMENT SCIENCE; V54 No. 10; pp. 1731-1746; OCT 2008.

  72. The new forestry biofuels sector; Pu YQ, Zhang DC, Singh PM, et al.; BIOFUELS BIOPRODUCTS & BIOREFINING-BIOFPR; V2 No. 1; pp. 58-73; JAN-FEB 2008.

  73. Development of a methodology for improving photovoltaic inverter reliability; Ristow A, Begovic M, Pregelj A, et al.; IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS; V55 No. 7; pp. 2581-2592; JUL 2008.

  74. Inventory management with advance demand information and flexible delivery; Wang T, Toktay BL; MANAGEMENT SCIENCE; V54 No. 4; pp. 716-732; APR 2008.

  75. Conceptual study of distributed CO2 capture and the sustainable carbon economy; Damm DL, Fedorov AG; ENERGY CONVERSION AND MANAGEMENT; V49 No. 6; pp. 1674-1683; JUN 2008.

  76. CHED 15-Infusing sustainability across the curriculum using our green chemistry project as a model; Collard DM, Smith JC, Kaplan LJ; ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY; V234; AUG 19 2007.

  77. Modeling of data center airflow and heat transfer: State of the art and future trends; Rambo J, Joshi Y; DISTRIBUTED AND PARALLEL DATABASES; V21 No. 2-3; pp. 193-225; JUN 2007.

  78. Characterization of fuel gas products from the treatment of solid waste streams with a plasma arc torch; Vaidyanathan A, Mulholland J, Ryu J, et al.; JOURNAL OF ENVIRONMENTAL MANAGEMENT; V82 No. 1; pp. 77-82; JAN 2007.

  79. Transportation planning and infrastructure delivery in major cities and megacities; Amekudzi AA, Thomas-Mobley L, Ross C; TRANSPORTATION RESEARCH RECORD No. 1997; pp. 17-23; 2007.

  80. Urban and rural temperature trends in proximity to large US cities: 1951-2000; Stone B; INTERNATIONAL JOURNAL OF CLIMATOLOGY; V27 No. 13; pp. 1801-1807; NOV 15 2007.

  81. Impacts of global climate change and emissions on regional ozone and fine particulate matter concentrations over the United States; Tagaris E, Manomaiphiboon K, Liao KJ, et al.; JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES; V112 No. D14 Article Number: D14312; JUL 31 2007.

  82. A study of secondary organic aerosol formation in the anthropogenic-influenced southeastern United States; Weber RJ, Sullivan AP, Peltier RE, et al.; JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES; V112 No. D13 Article Number: D13302; JUL 6 2007.

  83. Understanding "urban planning in China"; Yang JW; JOURNAL OF THE AMERICAN PLANNING ASSOCIATION; V73 No. 2; pp. 238-238; SPR 2007.

  84. The role of bathhouses and sex clubs in HIV transmission - Findings from a mathematic model; Faissol DM, Swann JL, Kolodziejski B, et al.; JAIDS-JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES; V44 No. 4; pp. 386-394; APR 1 2007.

  85. Finding an impact of preservation policies: Price effects of historic landmarks on attached homes in Chicago, 1990-1999; Noonan DS; ECONOMIC DEVELOPMENT QUARTERLY; V21 No. 1; pp. 17-33; FEB 2007.

  86. From honeybees to Internet servers: biomimicry for distributed management of Internet hosting centers; Nakrani S, Tovey C; BIOINSPIRATION & BIOMIMETICS; V2 No. 4; pp. S182-S197; DEC 2007.

  87. GREEN BUILDING POLICY OPTIONS FOR THE PUBLIC SECTOR; Pearce AR, DuBose JR, Bosch SJ; JOURNAL OF GREEN BUILDING; V2 No. 1; pp. 156-174; WIN 2007.

  88. Tunable solvents for fine chemicals from the biorefinery; Eckert C, Liotta C, Ragauskas A, et al.; GREEN CHEMISTRY; V9 No. 6; pp. 545-548; JUN 2007.

  89. Developing an 'energy sustainability index' to evaluate energy policy; Brown MA, Sovacool BK; INTERDISCIPLINARY SCIENCE REVIEWS; V32 No. 4; pp. 335-349; DEC 2007.

  90. Stakeholder perceptions of scientists: Lake Tahoe environmental policy from 1984 to 2001; Weible CM; ENVIRONMENTAL MANAGEMENT; V40 No. 6; pp. 853-865; DEC 2007.

  91. Transportation system Sustainability issues in high-, middle-, and low-income economies: Case studies from Georgia (US), South Korea, Colombia, and Ghana; Jeon CM, Amekudzi AA, Vanegas J; JOURNAL OF URBAN PLANNING AND DEVELOPMENT-ASCE; V132 No. 3; pp 172-186; SEP 2006.

  92. Deconstructing to redevelop - A sustainable alternative to mechanical demolition; Leigh NG, Patterson LM; JOURNAL OF THE AMERICAN PLANNING ASSOCIATION; V72 No. 2; pp 217-225; SPR 2006.

  93. Advanced technologies for earthquake risk inventories; French SP, Muthukumar S; JOURNAL OF EARTHQUAKE ENGINEERING; V10 No. 2; pp. 207-236; MAR 2006.

  94. Modeling study of air pollution due to the manufacture of export goods in China's Pearl River Delta; Streets DG, Yu C, Bergin MH, et al.; ENVIRONMENTAL SCIENCE & TECHNOLOGY; V40 No. 7; pp. 2099-2107; APR 1 2006.

  95. The influence of aerosols on crop production: A study using the CERES crop model; Greenwald R, Bergin MH, Xu J, et al.; AGRICULTURAL SYSTEMS; V89 No. 2-3; pp. 390-413; SEP 2006.

  96. Urban form and watershed management: how zoning influences residential stormwater volumes; Stone B, Bullen JL; ENVIRONMENT AND PLANNING B-PLANNING & DESIGN; V33 No. 1; pp. 21-37; JAN 2006.

  97. Numerical studies of the effects of active and passive circulation enhancement concepts on wind turbine performance; Tongchitpakdee C, Benjanirat S, Sankar LN; JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME; V128 No. 4; pp. 432-444; NOV 2006.

  98. Mixing politics and science in testing the hypothesis that greenhouse warming is causing a global increase in hurricane intensity; Curry JA, Webster PJ, Holland GJ; BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY; V87 No. 8; pp. 1025-+; AUG 2006.

  99. Joint life-cycle dynamics of new and remanufactured products; Debo LG, Toktay LB, Van Wassenhove LN; PRODUCTION AND OPERATIONS MANAGEMENT; V15 No. 4; pp. 498-513; WIN 2006.

  100. The effect of competition on recovery strategies; Ferguson ME, Toktay LB; PRODUCTION AND OPERATIONS MANAGEMENT; V15 No. 3; pp. 351-368; FAL 2006.