Proceedings pro099 : 1st International Conference on Bio-based Building Materials ICBBM 2015

Title: Proceedings of the 1st International Conference on Bio-based Building Materials
Edited by: Sofiane Amziane and Mohammed Sonebi
e-ISBN: 978-2-35158-154-4
Pages: 751
Publication date: 2015

The ICBBM2015 is an international forum for information dissemination and exchange, discussions and debates on research and practice related to innovative bio-construction materials and technologies with objectives for sustainable development.
“We aim to be this century’s leader in sustainable materials”. Biomaterials are processed or engineered products obtained partially or fully from renewable biobased resources, including: natural fibre composites, bioplastics, biorubbers, biofoams, bioadhesives, bioinks, biobased paints and coatings.
The conference attracted 150 people from several countries representing a wide range of academics, scientists, researchers, students, designers, policy makers and other industrialists from a wide variety of backgrounds, including fields of engineering, materials, sustainable, architecture, and ecological technologies, biomaterials, materials sciences, environmental engineering and government agencies, en-users, etc. Participants have the opportunity to share ideas on the state-of-the-art innovations, state-of-the-practice and future trends of bio-based building materials and sustainable materials used in construction.
The ICBBM2015 proceedings include the lectures and papers presented at ICBBM conference. It consists of a book of full texts of papers: 27 invited papers and 120 technical papers from over 32 countries. The keynotes, the papers and poster papers were presented in four parallel sessions which covered a wide spectrum of the topics related to natural fibres and materials, mechanical performances of bio-based building materials, hygroscopic and hygrothermal properties of biomaterials, acoustic and durability performance of bio-materials, eco-friendly binders with low CO2-emission and low embodied carbon energy, advances in research methodologies and bio-materials testing, rammed earth, life-cycle assessment of materials and others.
On behalf of the local organizing committee of ICBBM2015, we would like to take this opportunity to express our sincere thanks to all our contributors and participants for their carefully prepared, stimulating and thought provoking manuscripts; to the co-organizers of the one-day pre-course on “Bio-based building materials and use of polysaccharide in building and construction materials” for their dedicated task; to the members of the Technical and Scientific Committee for their time and effort of reviewing the papers and their valuable assistance, without which the conference could not be formed.
The organization of a conference of this scale could not have been possible without the support and contributions of many organizations and individuals, notably without the financial support given by the numerous sponsors. We also value the support of RILEM organization (The International Union of Laboratories and Experts in Construction Materials, Systems and Structures) and American Concrete Institute (ACI).
Thanks go to all those who have devoted their time and effort to the organization of the conference and publication of the proceedings, including secretarial staffs and research students of the ICBBM2015 for their diligent work and commitment to bring this conference to great success!


Author(s): Sofiane Amziane and Mohammed Sonebi
Pages: 12-12


Coir - Traditionally used fibres for new construction applications
Author(s): E. Kürsten
Pages: 18-22

Bio based concrete with crushed rape straw, a good alternative to develop an affordable bio based concrete for construction and renovation
Author(s): B. Laidoudi, C. Flamin, A. Crigny, J. Ferrari, G. Galzy, B. Dupré
Pages: 23-30

Development of guadua angustifolia prefabricated panels
Author(s): R.G. Morán, H.F. Silva, J.J. García
Pages: 31-35

The effect of sodium hydroxide surface treatment on the tensile strength of cellulose nanofibre
Author(s): R. K. Leung, S. Panthapulakkal, M. Sain and D. K. Panesar
Pages: 36-39

Effect of sheep wool fibres on thermal-insulation and mechanical properties of cement matrix
Author(s): A. Valenza, V. Fiore, A. Nicolosi, G. Rizzo, G. Scaccianoce, G. Di Bella
Pages: 40-45

Nonwoven flax fiber mats and white portland cement composites for building envelopes
Author(s): L.J. Fernández, J. Claramunt, A. Llerena, D. Torrens, M. Ardanuy, J.L. Zamora
Pages: 46-51

Effect of zirconates and silanes treatments on the physical and mechanical properties of flax fibers for applications in cementitious composites
Author(s): L. Boulos, M. Foruzanmehr, M. Robert
Pages: 52-56

Basalt fiber as reinforcement for lime-based mortars
Author(s): G. Quattrociocchi, M. Valente, F. Sarasini, J. Tirillò; M.L. Santarelli
Pages: 57-62

Mechanical characterization of natural fibre-reinforced earth plasters
Author(s): F.Rojat, M.Olivier, A.Mesbah, BF. Xiao
Pages: 64-71

Numerical modeling of rammed earth constructions: analysis and recommendations
Author(s): R. El Nabouch, Q.-B. Bui, P. Perrotin, O. Plé, J.-P. Plassiard
Pages: 72-79

Development of a self-compacted clay based concrete - Rheological, mechanical and environmental investigations
Author(s): G. Landrou, C. Brumaud, G. Habert
Pages: 80-84

Mechanical properties of unstabilized earth compressed at high pressures
Author(s): A.W. Bruno, D. Gallipoli, C. Perlot, J. Mendes, N. Salmon
Pages: 85-92

Investigation into the shear behaviour of rammed earth using shear box tests
Author(s): A. Corbin, C. Augarde
Pages: 93-98

Mode of operation of polysaccharide stabilising agent in cement based systems and interactions with superplasticisers
Author(s): W. Schmidt
Pages: 100-106

Lime activation of fly ash in mortar in the presence of metakaolin
Author(s): JM. Khatib, E. Onaidhe, M. Sonebi, H. Abdelgader
Pages: 107-110

Properties of alkali activated mortars with combinations of different starting materials
Author(s): B. Akturk, A.B. Kizilkanat, N.Kabay
Pages: 111-115

Humins as promising material for producing sustainable polyssacharide-derived building materials
Author(s): Alice Mija, Jan C. van der Waal, Jean-Mathieu Pin, Nathanael Guigo, Ed de Jong
Pages: 116-121

Influence of simulated desuphurised waste on the pore size distribution of cement pastes at 28 days of curing
Author(s): JM. Khatib, L. Wright, PS. Mangat, M. Sonebi
Pages: 122-125

The effect of glucose on the hydration kinetics of ordinary portland cement
Author(s): G.C.H. Doudart de la Grée, Q.L. Yu, H.J.H. Brouwers
Pages: 126-131

Effect of curing condition on shrinkage reducing property of self-consolidating concrete with different expansive admixtures
Author(s): Qi Cao, Kamal H. Khayat
Pages: 132-137

Desulphurised residues effect on the porosity and pore size distribution of cement based pastes during the early ages of curing
Author(s): JM. Khatib, L. Wright, PS. Mangat, M. Sonebi
Pages: 138-140


Study the development of mould on prompt natural cement-based hemp concrete
Author(s): L. Bessette, B. Trémerie, T. Béjat, A. Piot, A. Jay, L. Barnes Davin
Pages: 142-148

Use of bio-based insulation materials in buildings: Modelling of hygrothermal conditions in use – Resistance of a wood fibre material to moulds according to climatic conditions
Author(s): J. Lamoulie, I. Le Bayon, M. Draghi, M. Roger, C. Pompeo, M. Gabille, M. Prégnac, M.Jequel, M. Kutnik
Pages: 149-155

Properties of bio-based insulation materials and their potential impact on indoor air quality
Author(s): D.Maskell, C. F. da Silva, K. Mower, C. Rana, A. Dengel, R. J. Ball, M. P. Ansell, P. J. Walker, A Shea
Pages: 156-163

Study of the microbial development impact on bio-based materials
Author(s): M. Gueguen, S. Moscardelli, L. Van Schoors, I. Nour, S. Marceau
Pages: 164-167

Bio-based foam for thermal insulation. Valorisation of CNSL (cashew nut shell liquid)
Author(s): A. Théveniaux, A. Crigny, J. Ferrari, A. Nguyen Van Nhien, D. Postel, B.Dupré
Pages: 168-172

Permeability and thermal conductivity of pre-cast lime and hemp concrete
Author(s): V. Picandet, P. Tronet, T. Colinart, T. Lecompte, M. Choinska
Pages: 173-181

Development of microorganism sampling methods on bio-based earth products intended for healthy, sustainable buildings
Author(s): A. Simons, A. Bertron, J.E. Aubert, A. Laborel-Préneron, C. Roux, C. Roques
Pages: 182-188

Performance of biobased insulation board from crop by-products and natural gums
Author(s): M. Palumbo, A. Navarro, P. Giraldo, B. Lesar, A. M. Lacasta
Pages: 189-196

Assessment of the durability of bio-based insulating materials
Author(s): S. Marceau, P. Glé, M. Gueguen, E. Gourlay, S. Moscardelli, I. Nour, S. Amziane, L. Abdellaoui
Pages: 198-202

Durability studies on lightweight plaster and straw fiber based material for building thermal insulation
Author(s): N. Belayachi, D. Hoxha, M. Slaimia
Pages: 203-207

Efficiency of high performance concrete types incorporating bio-materials like rice husk ashes, cassava starch, lignosulfonate, and sisal fibres
Author(s): W.Schmidt, N.S.Msinjili, S.Pirskawetz, H-C.Kühne
Pages: 208-214

Protein-based biomaterials for temporary construction
Author(s): W.V. Srubar III, K.M. Hess, D.N. Dorr, L.S. Traeger, S.D. Frazier
Pages: 215-219

Impact of hygrothermal ageing of low-density polyethylene/short flax fibre composites on the multiscale properties
Author(s): Hajer Rabii, Laetitia Van Schoors, Marielle Gueguen, Peter Davies
Pages: 220-226

Comparing hemp composites made with mineral or organic binder on thermal, hygric and mechanical point of view
Author(s): F. Collet, S. Pretot, B. Mazhoud, L. Bessette, C. Lanos
Pages: 228-234

Investigation of mechanical performances of insulating building materials based on rice husk and hemp hurd
Author(s): M. Chabannes, E. Garcia-Diaz, L. Clerc, J-C. Bénézet
Pages: 235-242

Experimental investigation on the performance of hybrid hemp-flax composite materials
Author(s): J. Page, M. Sonebi, S. Amziane
Pages: 243-250

Effect of sugarcane bagasse fibre on the strength properties of soil blocks
Author(s): Humphrey Danso, D. Brett Martinson, Muhammad Ali, John B. Williams
Pages: 251-256

Development of polymer-reinforced flax fibre for the strengthening of reinforced concrete
Author(s): A. Hallonet, L. Michel, E. Ferrier
Pages: 257-264

Hemp concrete using innovative pozzolanic binder
Author(s): T. M. Dinh, C. Magniont, M. Coutand, G. Escadeillas
Pages: 265-270

Effect of various moisture content on the mechanical and viscoelastic properties of giant reed Arundo donax L.
Author(s): F. Nicoletti, V. Fiore, R. Tavolanti, T. Scalici, A. Valenza
Pages: 271-274

Performance of clay-straw plasters containing natural additives
Author(s): A. Navarro, M. Palumbo, B. Gonzalez, A.M. Lacasta
Pages: 275-280

Study of lime and hemp concrete (lhc) – Mix design, casting process and mechanical behaviors
Author(s): T. Lecompte, P. Tronet, V. Picandet, C. Baley
Pages: 281-288

Design and properties of mortar with seashells fine aggregates
Author(s): D. Carro-López, B. González-Fonteboa, C. Martínez, F. Martínez-Abella, S. Seara-Paz, R. Rodríguez
Pages: 289-294

Performance of a hybrid concrete structure with natural fibre reinforcements
Author(s): Libo Yan
Pages: 295-300

Enhancement of lime-hemp concrete properties using different manufacturing technologies
Author(s): M. Sinka, L. Radina, G. Sahmenko, A. Korjakins, D. Bajare
Pages: 301-308

Investigation of the mechanical performance and drying shrinkage of hemp concrete
Author(s): A. Kashtanjeva, M. Sonebi, S. Amziane
Pages: 309-315

Bacterial calcification in cement pastes and mortars containing mineral admixtures
Author(s): Z. Bundur, R. Ferron, M.J. Kirisits
Pages: 316-323

Characterization of live, dead, starved, and heat-treated S. pasteurii cells: implications for biomineralization in construction materials
Author(s): Sarah L. Williams, Mary Jo Kirisits, Raissa Douglas Ferron
Pages: 324-330

Application of soil bacteria to improve compressive strength of portland cement
Author(s): R.S.Dhone, M.V.Latkar, T.Charkraborty, R.V.Ralegaonkar
Pages: 331-333

RRT3: Statistical analysis of hemp concrete mechanical properties variability
Author(s): César Niyigena, Sofiane Amziane, Alaa Chateauneuf, Laurent Arnaud, Laetitia Bessette, Florence Collet, Gilles Escadeillas, Christophe Lanos, Mike Lawrence, Camille Magniont, Sandrine Marceau, Sara Pavia, Ulrike Peter, Vincent Picandet, Mohamed Sonebi, Pete Walker
Pages: 334-340

The use of wool as fiber-reinforcement in cement-based mortar
Author(s): Alessandro P. Fantilli, Silvio Sicardi, Francesca Dotti
Pages: 341-346

Investigation of performance tests using bio-derived/chemical additives
Author(s): J. Podolsky, A. Buss, R.C. Williams, E. Cochran
Pages: 347-354

A novel pull-out device used to study the influence of pressure during processing of cement-based material reinforced with coir
Author(s): A. Subrianto, T. Lecompte, A. Perrot, A. Le Duigou, G. Ausias
Pages: 355-362

Effects of shell element on shelled compressed earth masonry units
Author(s): C. Egenti, J. M. Khatib
Pages: 363-367

Rheological and mechanical behavior of earth materials / starch mixes
Author(s): Ghaith Alhaik, Michel Ferreira, Vincent Dubois, Eric Wirquin, SébastienTilloy, Eric Monflier, George Aouad
Pages: 368-375

Effects of seashell aggregates in concrete properties
Author(s): B. Gonzalez, D. Carro, F. Martínez-Abella, C. Martínez, S. Seara-Paz
Pages: 376-382

Effect of wetting and drying cycles on the interface of natural fibers with a portland cement based matrix
Author(s): Saulo Rocha Ferreira, Flávio de Andrade Silva, Paulo Roberto Lopes Lima, Romildo Dias Toledo Filho
Pages: 383-388

An orthotropic incremental model for the hydromechanical behaviour of softwood
Author(s): S.L. Nguyen, J.F. Destrebecq
Pages: 389-394

Effect of calcined nanoclay on microstructural and mechanical properties of chemically treated hemp fabric-reinforced cement nanocomposites
Author(s): Hakamy A, Shaikh FUA, Low IM
Pages: 395-399

Investigating the strain rate-dependent compressive properties of fiber-reinforced soy-based polyurethane foams
Author(s): N.Obaid, M. Kortschot, M. Sain
Pages: 400-404

Compressive and shearing behavior of lime and hemp concrete
Author(s): A. Youssef, T. Lecompte, V. Picandet, N. Challamel
Pages: 405-411

Probabilistic improvement of crack propagation monitoring by using acoustic emission: application to wood components
Author(s): M. Diakhaté, E. Bastidas-Arteaga, F. Schoefs
Pages: 412-415

Investigation of the mechanical performance and weathering of hemp concrete
Author(s): M. Sonebi, S. Wana, S. Amziane, J. Khatib
Pages: 416-421

Design of mechanically enhanced concrete using hemp shiv
Author(s): S. Amziane, V. Nozahic, M. Sonebi
Pages: 422-426

Fracture analysis of wood under variable environment
Author(s): N. Angellier, R. Moutou Pitti, F. Dubois
Pages: 427-428

Impact of the water content of hemp concretes on their thermal and acoustical properties
Author(s): E. Gourlay, P. Glé, C. Foy, S. Marceau, S. Moscardelli
Pages: 430-436

Mechanical and acoustical behavior of starch-hemp bio-composite materials
Author(s): A.T. Le, A. Gacoin, A.Li, T.H. Mai, N. El Wakil
Pages: 437-444

In situ damage monitoring in timber materials: acoustic emission pattern recognition approach based on Hilbert–Huang transform
Author(s): S.E. Hamdi, M. Diakhaté, R. Moutou Pitti, F. Dubois, A. Chateauneuf
Pages: 445-448

Acoustical characterization and modelling of agricultural by-products for building insulation
Author(s): E. Gourdon, P.A. Chabriac, P.Glé, A. Fabbri, F. McGregor
Pages: 449-453

Moisture buffer potential of wall assemblies incorporating hemp-lime
Author(s): E. Latif, M. Lawrence, A. Shea, P. Walker
Pages: 455-459

Evaluation and application of Opuntia ficus-indica panel
Author(s): A.De Vecchi, A. Valenza, S. Colajanni, E. Sanfilippo, V. Fiore, A. Lanza Volpe
Pages: 460-466

3D X-ray tomography for the hygrothermal characterization of spruce wood
Author(s): C. El Hachem, K. Abahri, R. Bennacer
Pages: 467-473

Measurement of the hygrothermal properties of straw-clay mixtures
Author(s): N. Oudhof, M.Labat, C.Magniont, P. Nicot
Pages: 474-479

A new treatment to reduce wood hydrophilicity
Author(s): K. Charlet, F. Saulnier, D. Gautier, M. Pouzet, M. Dubois, A. Béakou
Pages: 480-487

Comparative study of hygrothermal performances of straw-clay and vertically perforated clay brick buildings
Author(s): E. Stéphan, D. Samri, B. Moujalled, F. Pesteil
Pages: 488-495

Influence of cellulose pulp fiber addition on the hydration of cementitious pastes with silica fume
Author(s): I. S. Siqueira, R. D. Toledo Filho, E. A. B. Koenders
Pages: 496-503

Bamboo panels to control moisture level of buildings
Author(s): Nguyen D. M., A.C. Grillet, J. Weiss, Phan Nguyen T. S., Diep Thi M. H., M. Woloszyn
Pages: 504-509

Moisture properties of rape straw concrete and hemp concrete
Author(s): M. Rahim, O. Douzane, A.D, Tran Le, G. Promis, T. Langlet
Pages: 510-516

Influence of straw content on the mechanical and thermal properties of bio-based earth composites
Author(s): A. Laborel-Préneron, J-E. Aubert, C. Magniont, A. Bertron
Pages: 517-522

Water transfers in hemp concrete followed by nuclear magnetic resonance
Author(s): Marine Fourmentin, Paméla Faure, Ulrike Peter, Didier Lesueur, Philippe Coussot
Pages: 523-525

Formulation of binder to improve mechanical properties of hemp concrete at early stage. Effect on thermal and hygric properties in use
Author(s): S. Pretot, F. Collet, C. Lanos, J. Chamoin
Pages: 526-533

Experimental and numerical evaluation of the hygrothermal performance of a hemp-lime building
Author(s): B. Moujalled, Y. Aït-Oumeziane, D. Samri, E. Stéphan, S. Moissette, M. Bart, C. Lanos
Pages: 534-541

Effect of compaction on moisture buffering of hemp-lime insulation
Author(s): N. Holcroft, A. Shea
Pages: 542-546

Hysteresis phenomenon in hemp concrete
Author(s): Y. Aït-Oumeziane, M. Bart, S. Moissette, C. Lanos, F. Collet, S. Pretot
Pages: 547-554

Heat transfer of dowelled and bolted steel-to-timber connections exposed to fire: Experimentation and numerical modeling
Author(s): A. Samaké, Ph. Audebert, M. Taazount
Pages: 555-559

Hygrothermal behavior of a hemp concrete wall: experimental and numerical study of coating
Author(s): A. Piot, T. Béjat, L. Bessette, A. Jay
Pages: 560-566

Effect of temperature on thermal and hygric properties of hemp-lime plasters
Author(s): B. Mazhoud, F. Collet, S. Pretot
Pages: 567-574

Experimental study of the hygrothermal behaviour of hemp shives-based precast blocks at material and wall scales
Author(s): T. L. Vu, S. Spagnol, C. Magniont
Pages: 575-582

A systematic methodology for sensitivity analysis in life cycle thinking context applied to hemp-based insulation products for buildings
Author(s): T. Senga Kiessé, A. Ventura, H.M.G. van der Werf, B. Cazacliu, R. Idir, Andrianandraina
Pages: 584-591

Environmental performance of north american wood panel manufacturing
Author(s): R. Bergman, D. Kaestner, A. Taylor
Pages: 592-598

Environmental impacts of agro-sourced materials compared to traditional materials into building
Author(s): Jérémy Ferrari, Antoine Crigny, Blaise Dupré
Pages: 599-603

Development of a laboratory test method to assess the resistance of bio-based insulation materials against moulds
Author(s): I. Le Bayon, M. Draghi, M. Gabille, M. Prégnac, J. Lamoulie, M.Jequel, M. Roger, M. Kutnik
Pages: 605-612

The “NatuRALiMe” project: New insights into the study of hemp-based mortars for new construction and heritage conservation
Author(s): A. Arizzi, H.Viles
Pages: 613-618

Characterization of hemp aggregates – Comparison of several size analysis
Author(s): S. Liandrat, M. Trauchessec, L. Blachère, S. Amziane
Pages: 619-623

On the mechanical characterization of a sunflower-based biocomposite using the grid method
Author(s): S. Sun, E. Toussaint, M. Grédiac, J.-D. Mathias
Pages: 624-628

Optimizing the design of timber components under decay and climate variations
Author(s): E. Bastidas-Arteaga, Y. Aoues, A. Chateauneuf
Pages: 629-634

Effect of testing variables on the hydration and compressive strength of lime hemp concrete
Author(s): S. Pavia, R. Walker, J. McGinn
Pages: 635-640

Indoor air emission tests of natural materials
Author(s): M. Richter, W. Horn, O. Jann, E. Juritsch, A. Klinge, E. Roswag, P. Fontana, L. Miccoli
Pages: 641-643


Thermal and hydrological modeling of green roofs: Application to stormwater management assessment
Author(s): R. Djedjig, R. Belarbi, M. El Ganaoui
Pages: 645-648

Environmentally friendly vege-roofing tile: an investigation study
Author(s): Habib, Noor Zainab; Zoorob, Salah Elias; Ng, Choon Aun; Mustaffa Zahiraniza; Kamaruddin, Ibrahim; Ya’cob AAsyran Syafiq, Sethupathi, Sumathi, Nadeem, Humayun; Sohaib, Mir Muhammad
Pages: 649-653

Impact of green roof in building energy performance: experimental and numerical study
Author(s): S. Ouldboukhitine, R. Belarbi
Pages: 654-660

Evaluation of micro-concrete fibre reinforced roofing tiles with scm
Author(s): H.C. Uzoegbo
Pages: 661-665

A new load-bearing insulation material made of cattail
Author(s): M. Krus, Th. Werner, Th. Großkinsky, G. Georgiev
Pages: 666-673

Preliminary study on use of terrazyme as a bio stabilizer along with cement and lime in compressed stabilized earth blocks
Author(s): M.V. Sravan, H.B. Nagaraj
Pages: 674-681

Particleboard with coir fiber and sugar cane bagasse: thermal-physical-mechanical properties
Author(s): S. Bonilla, G. Marmol, J. Fiorelli, H. Savastano Jr
Pages: 682-686

Sensitivity analysis of parameters influencing building heating energy consumption using hemp-lime material
Author(s): Andrianandraina, P. Poullain, B. Cazacliu, A. Ventura
Pages: 687-694

Wood-strand sandwich panels for panelized construction
Author(s): N. White, C. Voth, V. Yadama
Pages: 695-697

Re-use of quarry fines for the production of blocks
Author(s): Dubois Vincent, Wirquin Eric, Flament Cédric, Schmid Christelle, Chartier Thierry
Pages: 698-704

100% biobased particleboards based on new agricultural wastes
Author(s): A. Mahieu, H. Lenormand, N. Leblanc, A. Vivet
Pages: 705-710

A review of recycled use of post consumer waste paper in construction
Author(s): Okeyinka Oriyomi M, Oloke David A, Jamal Khatib
Pages: 711-717

Comparative environmental life cycle assessment of vegetative roofs: A case study from lebanon
Author(s): Makram El Bachawati, Rima Manneh, Thomas Dandres, Carla Nassab, Henri El Zakhem, Rafik Belarbi
Pages: 718-719

Sustainable building with local material: a case study
Author(s): V.-H. Tran, J.-C. Morel, Q.-B. Bui, S. Hans, M. Oggero
Pages: 721-726

GROW2BUILD - Local cultivated hemp and flax as resource for biobased building materials
Author(s): J.T.W. Verhoeven, J.E.G. van Dam, L. Gaquere
Pages: 727-732

Which techniques and strategies employ to foster new local commodity chains for bio-based materials? Results of a multidisciplinary scientific research
Author(s): Jérémie Joubert, Florian Rollin, Sabrina Brullot, Nicolas Buclet
Pages: 733-738

Sustainability assessment of industrialized bamboo solutions for housing programs in the Philippines
Author(s): E. Zea Escamilla, G. Habert, E. Wohlmuth, F. Martirena
Pages: 739-746