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A challenging issue is the dynamics of nanoporous solids after the insertion of molecular rotors in their building blocks and promises access to the control of rotary motion by chemical and physical stimuli.[1] The combination of porosity with ultra-fast rotor dynamics was discovered in molecular crystals, covalent organic frameworks and MOFs by 2H spin-echo NMR spectroscopy and T1 relaxation times.[2-5] The rotors, as fast as 1011 Hz at 150 K, are exposed to the crystalline channels, which absorb CO2 and I2 from the gas phase, even at low pressures. Interestingly, the rotor dynamics can be switched on and off by vapor absorption/desorption, showing a remarkable change of material dynamics, which, in turn, produces a modulated physical response. Novel mesoporous organosiloxane frameworks allowed us to realize periodic architectures of fast molecular rotors on which C-F dipoles are mounted.[6] These dipolar rotors showed not only rapid dynamics (109 Hz at 325 K) in solid-state NMR experiments, but also a dielectric response typical of a fast dipole reorientation. Moreover, crystals with permanent porosity were exploited in an unusual way to decorate crystal surfaces with regular arrays of dipolar rotors. The inserted molecules carry alkyl chains which are included as guests into the channel-ends.[7] The rotors stay at the surface due to a bulky molecular stopper which prevents the rotors from entering the channels. In a final example, flexible molecular crystals were fabricated by a series of shape-persistent azobenzene tetramers that form porous molecular crystals in their trans configuration. The efficient trans→cis photoisomerization of the azobenzene units converts the crystals into a non-porous phase but crystallinity and porosity are restored upon Z→E isomerization promoted by visible light irradiation or heating. We demonstrated that the photoisomerization enables reversible on/off switching of optical properties as well as the capture of CO2 from the gas phase.[8] We would like to thank Cariplo Foundation/Lombardy Region/INSTM Consortium. References 1. A. Comotti, S. Bracco, P. Sozzani Acc. Chem. Res. 2016, 49, 1701. 2. S. Bracco, et al Chem. Eur. J. 2017, 23, 11210. 3. A. Comotti, et al J. Am. Chem. Soc. 2014, 136, 618. 4. A. Comotti, et al Angew. Chem. Int. Ed. 2014, 53, 1043. 5. S. Bracco, et al Chem. Comm. 2017, 53, 7776. 6. S. Bracco, et al Angew. Chem. Int Ed. 2015, 54, 4773. 7. L. Kobr, et al J. Am. Chem. Soc. 2012, 134, 10122. 8. M. Baroncini et al. Nature Chem. 2015, 7, 634.

Our approach is to design porosity in combination with switchable dynamics and flexibility in porous materials for gaining control over gas capture and selectivity. This approach was made possible by fabricating rotor-on-axel molecular struts and tetrahedral building blocks. Ultra-fast molecular rotors as fast as 1011 Hz were engineered in porous crystalline frameworks (molecular crystals, MOFs and mesoporous organosilicas) containing rod-like linkers as amphidynamic elements. The porous frameworks promise access to the control of rotary motion by chemical and physical stimuli. If a gas or a vapor is diffused to the cavities, such as CO 2, iodine and hydrocarbon vapors, rotor dynamics is hampered. In turn, on/off switching produces modulated physical responses. When C-F dipoles were mounted on the rotors, they induced fast oscillating dipoles that interact with an applied electric field. Direct evidence of hostguest interactions at the molecular level were established by 2D solid-state NMR. We achieved the fabrication of swellable porous adamantoid frameworks by the use of highly symmetrical tetrahedral elements and the co-operation of 8 surrounding hydrogen bonds mounted on conformationally flexible groups. The flexibility of the porous crystals manifests itself in response to stimuli of selected gases: CO2, Xe and hexane triggers the enlargement of channel cross-section. The accomodation of CO2 and Xe in the channel chambers was revealed by synchrotron-light XRD, combined with modelling. Xenon dynamics was gathered by 129Xe NMR chemical shift anisotropy profiles, which encode the shape and orientation of each visited cavity. Jump rate and activation energy experienced by exploring Xe atoms were uniquely established. Covalent connection of tetrahedral nodes results in expandable frameworks, especially if 3 instead of all 4 branches are cross-linked: the forth branch can be dedicated to bearing a functional group to catch the gas molecules (CO 2 is retained by –NH2 group by an energy as high as 54 kJ/mol). Moreover, photo-responsive molecular crystals were fabricated by tetrahedral azobenzene tetramers that form porous molecular crystals in their trans configuration. The efficient trans-to-cis photoisomerization converts the crystals into a non-porous phase but crystallinity and porosity are restored upon reverse isomerization promoted by heat. We demonstrated that the photo-isomerization enables reversible on/off switching of optical properties as well as CO2 capture from the gas phase. We thank Cariplo Foundation, Lombardy Region/INSTM Consortium and PRIN 2016. References 1. Acc.Chem.Res.2016,49,1701; 2. Chem.Eur.J. 2017,23,11210; 3. J.Am.Chem.Soc.2014,136,618; 4. Angew.Chem.Int.Ed. 2014,53,1043. 5. Chem.Comm.2017,53,7776; 6. J.Mater.Chem.A2018,6,14231; 7. Chem.Comm. DOI:10.1039/C8CC03951H; 8. NatureChem. 2015,7,634.

The enormous interest manifested in recent years for porous materials has generated efficient systems for adsorbing gases of great interest for energy and the environment, such as CO2, CH4 and H2. Our approach was to design porosity in combination with switchable dynamics and flexibility for gaining control over gas capture and selectivity. This approach was made possible by fabricating rotor-on-axel molecular struts and tetrahedral building blocks. Rotor-on-axel molecular struts. Ultra-fast molecular rotors were realized in porous solids by engineering crystalline frameworks (molecular crystals, MOFs and mesoporous organosilicas) containing rod-like linkers as amphidynamic elements.1-5 The porous frameworks promise access to the control of rotary motion by chemical and physical stimuli. We prepared rotors as fast as 1011 Hz (in the regime of conventional liquids) in properly designed porous crystals. Rotor dynamics was successfully hampered by the diffusion of gases or vapors. In turn, the on/off switching of dynamics produces modulated physical responses when C-F dipoles were mounted on the rotors.6 Direct evidence of host-guest relationships and interactions at the molecular level were established by 2D solid-state NMR and modelled by ab initio calculations. Tetrahedral building-blocks. In the search for flexible molecular crystals endowed with porosity, we achieved the fabrication of expandable crystalline prototypal structures, which allow for the absorption of gases, without modifying the crystal architecture.7 The design brings together highly symmetrical tetrahedral elements to construct swellable porous adamantoid frameworks. The flexibility of the porous crystals manifests itself in response to stimuli of selected gases: the contact with CO2, Xe and hexane triggers the enlargement of channel cross-section and capacity. The accomodation of CO2 and Xe in the channel chambers was revealed by synchrotron-light XRD, combined with Molecular Dynamics and DFT calculations. Xenon dynamics, exploring various cavity orientations in the crystal, were gathered by 129Xe NMR chemical shift anisotropy profiles, which encode the shape and orientation of each visited cavity. Jump rate and activation energy experienced by exploring Xe atoms were uniquely established. Moreover, photo-responsive molecular crystals were fabricated by a series of tetrahedral azobenzene tetramers that form porous molecular crystals in their trans configuration.8 The efficient trans-to-cis photoisomerization of the azobenzene units converts the crystals into a non-porous phase but crystallinity and porosity are restored upon cis-to-trans reverse isomerization promoted by visible light or heat. We demonstrated that the photo-isomerization enables reversible on/off switching of optical properties as well as CO2 capture from the gas phase. Acknowldegements to PRIN 2016 2016-NAZ-0104 (1) A. Comotti, A. et al. Acc. Chem. Res. 49 (2016) 1701-1710. (2) S. Bracco, et al. Chem. Eur. J. 23 (2017) 11210. (3) A. Comotti, et al. J. Am. Chem. Soc. 136 (2014) 618. (4) A. Comotti, et al. Angew. Chem. Int. Ed. 53 (2014) 1043. (5) S. Bracco, et al. Chem. Comm. 53 (2017) 7776. (6) S. Bracco, et al. Angew. Chem. Int Ed. 54 (2015) 4773. (7) I. Bassanetti, et al. J. Mater. Chem. A 6 (2018) 14231. (8) M. Baroncini, et al. Nature Chem. 7 (2015) 634.

Molecular rotors, especially when bearing dipoles, are a challenging research field entailing a number of useful phenomena, such as switchable ferroelectricity, and the fabrication of dynamic elements of molecular motors in solids. The combination of remarkable porosity with ultra-fast rotor dynamics was discovered by our group in molecular crystals and covalent frameworks, by 2H spin-echo NMR spectroscopy and T1 relaxation times [1-3]. Molecular rotors, as fast as 107 Hz at 200 K, are exposed to the crystalline channels, which absorb CO2 and I2 vapors even at low pressure. Interestingly, the rotor dynamics could be controlled by I2 absorption/desorption, showing a remarkable change of material dynamics and suggesting the use of porous crystals in sensing and pollutant management. Novel mesoporous organosiloxane frameworks, obtained by a self-assembly process, allowed to realize periodic architectures of fast molecular rotors containing dynamic C-F dipoles in their structure (Fig. 1a) [4]. The dipolar rotors showed not only the rapid dynamics of the aromatic rings (ca. 5x108 Hz at 325 K) (Fig. 1b), but also a dielectric response typical of a fast dipole reorientation under the stimuli of an applied electric field. Molecular rotors were mounted on crystal surfaces exploiting the formation of surface inclusion compounds. Guest molecules engineered as three segments comprising a shaft, a stopper, and a rotator can interact with a porous crystal and insert the shaft into the bulk crystal, while the rotator lies on the surface[5]. The host-guest relationships were established by 2D solid state NMR and low rotational barriers were found by dielectric spectroscopy.

Crystalline porous materials are excellent candidates for the fabrication of molecular rotors in the solid state.1 The combination of remarkable porosity with ultra-fast rotor dynamics was discovered in molecular crystals and metal-organic frameworks (MOFs) by 2H spin-echo NMR spectroscopy and T1 relaxation times. Molecular rotors are exposed to the crystalline channels, which absorb CO2 and I2 vapors even at low pressure. Interestingly, dynamics could be controlled by I2 absorption/desorption, showing a remarkable change of material dynamics and suggesting the use of porous crystals in pollutant management. 2,3 A microporous MOF engineered to contain in its scaffold rod-like struts [1,4-bis(1H-pyrazol-4-ylethynyl)benzene] showed extremely rapid 180° flip reorientation of the central p-phenylene unit with rotational rates of 1011 Hz at 150 K. The permanent porosity of the crystals is demonstrated by CO2 adsorption isotherms at various temperatures and the selectivity of the MOF toward CO2/N2 binary mixtures is associated with the interaction energy, estimated to be 25 kJ mol-1, indicating a good interaction of CO2 with the channel walls. Crystal-pore accessibility of the MOF allowed the CO2 molecules to enter the cavities and control the molecular rotor spinning speed down to 105 Hz at 150 K (Fig. 1). 4 This strategy enabled the regulation of rotary motion by the diffusion of the gas within the channels and the determination of the energetics of rotary dynamics in the presence of CO2. This unique response of the materials to CO2 is of great importance for the environment, enlarging perspectives in the field of sensors and gas detection.

A challenging issue is the dynamics of porous solids and the insertion of molecular rotors in their building blocks, promising access to the control of rotary motion by chemical stimuli. The combination of porosity with ultra-fast rotor dynamics was discovered in molecular crystals and covalent frameworks, by 2H spin-echo NMR spectroscopy and T1 relaxation times.[1-3] The rotors, as fast as 107 Hz at 200 K, are exposed to the crystalline channels, which absorb CO2 and I2 vapors even at low pressure. Interestingly, the rotor dynamics can be switched on and off by vapor absorption/desorption, showing a remarkable change of material dynamics. Novel mesoporous organosiloxane frameworks allowed to realize periodic architectures of fast molecular rotors containing dynamic C-F dipoles in their structure.[4] The dipolar rotors showed not only the rapid dynamics of the aromatic rings (ca. 5108 Hz at 325 K), as detected by solid-state NMR spectroscopy, but also a dielectric response typical of a fast dipole reorientation under the stimuli of an applied electric field. Crystals with permanent porosity were exploited in an unusual way to decorate crystal surfaces with regular arrays of dipolar rotors. The inserted molecules carry alkyl chains which are included as guests into the channel-ends.[5] The rotors stay at the surface due to a bulky molecular stopper which prevents the rotors from entering the channels. The host-guest relationships were established by 2D solid-state NMR and GIAO HF ab initio calculations. Flexible molecular crystals were fabricated by a series of shape-persistent azobenzene tetramers that form porous molecular crystals in their trans configuration. The efficient trans→cis photoisomerization of the azobenzene units converts the crystals into a non-porous phase but crystallinity and porosity are restored upon Z→E isomerization promoted by visible light irradiation or heating. We demonstrated that the photoisomerization enables reversible on/off switching of optical properties as well as the capture of CO2 from the gas phase.[6] Control of molecular rotor dynamics by I2 molecule absorbed in the channels of a porous molecular crystal shown below.

Molecular Rotors, especially when bearing dipoles, are an attractive research field entailing a number of useful phenomena, such as switchable ferroelectricity, and the fabrication of dynamic elements of molecular motors in solids. In turn, porous materials are an innovative playground for supporting switchable molecular rotors.[1,2] We have recently discovered hybrid porous materials with intrinsic dynamics due to the presence of fast molecular rotors in their architectures [3,4]. The highly-organized porous scaffolds supporting organic elements allowed the fabrication of fast molecular rotors (k>108 Hz), such as p-phenylene units and dipolar rotors containing C-F dipoles. Such dipolar rotors face the pores and are entirely exposed to the guest molecules which acted as regulators. In a particular example iodine enters the channels and selectively reacts with the double bonds of the divinyl-fluoro-p-phenylene rotors without disrupting the structure, affecting their motion and the dielectric properties.Moreover, we exploited the photoisomerization of molecular crystals containing star-shaped molecules engineered in such a way that photoisomerizable units are attached to a C-atom node [5]. The starting crystal is porous and shows gas adsorption while the modification of molecular shape induced by the irradiation produces a change in adsorption properties. The phenomenon is reversible by relaxation of the molecules, upon heating and visible light irradiation, to the more stable isomer. A gas can be pumped in and out a photoswitchable material, producing a pressure change in a closed vessel: by this actuator work can produced from radiative energy

Molecular Rotors, especially when bearing dipoles, are an attractive research field entailing a number of useful phenomena, such as switchable ferroelectricity, and the fabrication of dynamic elements of molecular motors in solids. In turn, porous materials are an innovative playground for supporting switchable molecular rotors.[1] We have recently discovered hybrid porous materials with intrinsic dynamics due to the presence of fast molecular rotors in their architectures [2,3]. The highly-organized porous scaffolds supporting organic elements allowed the fabrication of fast molecular rotors (k>108 Hz), such as p-phenylene units and dipolar rotors containing C-F dipoles. Such dipolar rotors face the pores and are entirely exposed to the guest molecules which acted as regulators. A first example of molecular rotors in porous molecular crystals is presented. Disulfonated rotor-containing molecular rods were self-assembled with alkylammonium salts to fabricate porous supramolecular architectures held together by charge-assisted hydrogen bonds[4]. The rotors are exposed to the crystalline channels, which absorb CO2 and I2 vapors at low pressure. The rotor dynamics could be switched off and on by I2 absorption/desorption, suggesting the use of porous crystals in sensing and pollutant management. Moreover, porosity can be switched on/off in molecular crystals based on star-shaped azobenzene tetramers by photoirradiation[5]. The trans-cis photoisomerization of the azobenzene units takes place in the solid state and converts the porous crystals into a non-porous amorphous phase while crystallinity and porosity are restored upon cis-trans isomerization promoted by visible light irradiation or heating. Photoisomerization enables reversible capture of carbon dioxide from the gas phase as demonstrated by CO2 adsorption isotherms. 1) Angew. Chem. 2014, 53, 1043; 2) Angew. Chem. 2015, ASAP (VIP); 3) Angew. Chem. 2010, 49, 1760; 4) JACS 2014, 136, 618; 5) Nature Chem. 2015, accepted

Highly porous materials are attracting large attention in the recent literature for their applications in the field of gas storage, selective recognition and molecular confinement. The discovery of ultra-fast molecular rotors in porous covalent frameworks allowed us to look at them from a new perspective [1,2]. The unusual combination of remarkable porosity with fast dynamics enabled the reversible speed-regulation of matrix rotors by the interaction with I2 vapors entering the galleries of the porous compounds. Molecular rotors, especially when bearing dipoles, are a challenging research field entailing a number of useful phenomena, such as switchable ferroelectricity, and the fabrication of dynamic elements of molecular motors in solids. Recently, fast rotating organic elements bearing carbon-fluorine dipoles have been fabricated in porous organic-inorganic hybrid periodic architectures [3]. The reactivity of the pivot bonds allowed halogen addition and motion regulation. A first example of molecular rotors in porous molecular crystals is presented. Disulfonated rotor-containing molecular rods were self-assembled with alkylammonium salts to fabricate porous supramolecular architectures held together by charge-assisted hydrogen bonds [4]. The rotors are exposed to the crystalline channels, which absorb CO2 and I2 vapors at low pressure. The rotor dynamics could be switched off and on by I2 absorption/desorption, suggesting the use of porous crystals in sensing and pollutant management. Moreover, crystals with permanent porosity were exploited in an unusual way to decorate crystal surfaces with regular arrays of dipolar rotors. The inserted molecules carry alkyl chains which are included as guests into the channel-ends [5]. The rotors stay at the surface due to a bulky molecular stopper which prevents the rotors from entering the channels. The host-guest relationships were established by 2D solid-state NMR and low rotational barriers were found by dielectric spectroscopy. [1] A. Comotti, S. Bracco, P. Valsesia, M. Beretta, P. Sozzani Angew. Chem. Int Ed., 2010, 49, 1760. [2] A. Comotti, S. Bracco, T. Ben, S. Qiu, P. Sozzani Angew. Chem., Int. Ed., 2014, 53, 1043. [3] S. Bracco, M. Beretta, A. Cattaneo, A. Comotti, A. Falqui, K. Zhao, C. Rogers, P. Sozzani, Angew. Chem. Int Ed., 2015, 54, 4773. [4] A. Comotti, S. Bracco, A. Yamamoto, M. Beretta, T. Hirukawa, N. Tohnai, M. Miyata, P. Sozzani J. Am. Chem. Soc., 2014, 136, 618. [5] L. Kobr, K. Zhao, Y. Shen, A. Comotti, S. Bracco, R. K. Shoemaker, P. Sozzani, N. A. Clark, J. Price, C. Rogers, J. Michl J. Am. Chem. Soc. 2012, 134, 10122.

Molecular Rotors, especially when bearing dipoles, are an attractive research field entailing a number of useful phenomena, such as switchable ferroelectricity, and the fabrication of dynamic elements of molecular motors in solids. In turn, porous materials are an innovative playground for supporting switchable molecular rotors [1]. We have recently discovered hybrid porous materials with intrinsic dynamics due to the presence of fast molecular rotors in their architectures [2,3]. The highly-organized porous scaffolds supporting organic elements allowed the fabrication of fast molecular rotors (k>108 Hz), such as p-phenylene units and dipolar rotors containing C-F dipoles. Such dipolar rotors face the pores and are entirely exposed to the guest molecules which acted as regulators. A first example of molecular rotors in porous molecular crystals is presented. Disulfonated rotor-containing molecular rods were self-assembled with alkylammonium salts to fabricate porous supramolecular architectures held together by charge-assisted hydrogen bonds[4]. The rotors are exposed to the crystalline channels, which absorb CO2 and I2 vapors at low pressure. The rotor dynamics could be switched off and on by I2 absorption/desorption, suggesting the use of porous crystals in sensing and pollutant management. In a further example, the surfaces of inclusion crystals were decorated with regular arrays of dipolar molecular rotors by the insertion of dipolar rotators carrying alkyl chains which are included as guests into channels of a host, tris(o-phenylenedioxy)cyclotriphosphazene (TPP) [5]. The rotors stay at the surface due to a bulky molecular stopper which prevents the rotors from entering the channels while the alkyl chains are included in the crystals. The host-guest relationships were established by 2D solid-state NMR and low rotational barriers were found by dielectric spectroscopy. Furthermore, porosity can be switched on/off in molecular crystals based on star-shaped azobenzene tetramers by photoirradiation [6]. The trans-cis photoisomerization of the azobenzene units takes place in the solid state and converts the porous crystals into a non-porous amorphous phase while crystallinity and porosity are restored upon cis-trans isomerization promoted by visible light irradiation or heating. Photoisomerization enables reversible capture of carbon dioxide from the gas phase as demonstrated by CO2 adsorption isotherms.

Background The standardization of the HER2 score and recent changes in therapeutic modalities points to the need for a reevaluation of the role of HER2 in recently diagnosed breast carcinoma. Patients and methods A multicenter, retrospective study of 1794 primary breast carcinomas diagnosed in Italy in 2000/2001 and scored in HER2 four categories according to immunohistochemistry was conducted. Results Ductal histotype, vascular invasion, grade, MIB1 positivity, estrogen and progesterone receptor expression differed significantly in HER2 3+ tumors compared with the other categories. HER2 2+ tumors almost showed values intermediate between those of the negative and the 3+ subgroups. The characteristics of HER2 1+ tumors were found to be in between those of HER2 0 and 2+ tumors. With a median follow-up of 54 months, HER2 3+ status was associated with higher relapse rates in node-positive and node-negative subgroups, while HER2 2+ only in node positive. Analysis of relapses according to type of therapy provided evidence of responsiveness of HER2-positive tumors to chemotherapy, especially taxanes. Conclusions The present prognostic significance of HER2 is correlated to receptor expression level and points to the need to consider HER2 2+ and HER2 3+ tumors as distinct diseases with different outcomes and specific features.

Réalisé dans le cadre du Programme de recherche urbaine pour le développement (PRUD). http://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers17-01/010038038.pdf; International audience; Peut-on parler d'un "modèle vietnamien" de ville asiatique ? A la différence de ce que l'on observe en Chine, il semblerait que la "transition urbaine" au Viêt-nam s'opère de façon moins radicale ou brutale. La capacité d'assimiler des modèles exogènes, la recherche d'une troisième voie entre dirigisme et libéralisme, la prise en compte du patrimoine architectural dans la planification urbaine sont autant de raisons de cette spécificité. Cet ouvrage, par le contenu de ses différents chapitres, et par les propositions de recherche formulées par ses auteurs, devrait être l'un des catalyseurs de la recherche urbaine sur le Viêt-nam.

Este trabajo presenta los resultados obtenidos en un estudio (tesis de grado) sobre las estrategias de producción orgánica de establecimientos familiares de dos departamentos del sur del Uruguay. Las principales bases conceptuales que enmarcan el estudio son las actuales concepciones de desarrollo sustentable y agricultura sustentable, y las diferentes corrientes dentro de la última. La metodología utilizada en este trabajo fue la de estudio de casos, seleccionando para ello diez establecimientos que se encuentran ya sea en un proceso de conversión a la agricultura orgánica o que utilizan esta forma de producción en toda la unidad productiva. Los establecimientos seleccionados se analizaron desde un enfoque holístico, tomando en cuenta todos los aspectos de los mismos y las interacciones que se establecen entre sí. Específicamente, se examinaron las estrategias que emplean los productores en la elección de rubros, manejo de los mismos, manejo de recursos naturales y energéticos, manejo sanitario, manejo postcosecha, uso de la mano de obra, comercialización, asesoramiento y capacitación, relacionamiento con la comunidad, y transición al manejo orgánico. Asimismo, se examinaron las motivaciones y objetivos respecto a la actividad agropecuaria, y los valores y opiniones que los productores expresan en relación a su forma de producción. Finalmente, se realizó un análisis comparativo de las estrategias empleadas por los productores estudiados con respecto a los componentes de los paradigmas de agricultura alternativa y convencional propuestos por los autores Beus y Dunlap (1990). This document presents the results of a study which focuses on organic production strategies developed by family farms located in two departments of the Southern region of Uruguay. The main theoretical streams that frame the study are the current concepts of sustainable development and sustainable agriculture, and the diverse trends within that paradigm. Case studies was the methodology used to examine the strategies, for which ten farms, either totally organic or in transition to being totally organic, were selected. Farm units are analyzed from a holistic perspective, taking into account all the components and the interactions among them. Specifically, the strategies examined are: criteria for selecting crops, crop management, natural and energetic resource management, plant health management, post-harvest management, use of labor force, marketing, technical assistance and training, relationship with the community, and transition strategies to organic production. In addition, farmers´motivations and objectives related to agriculture as a way of life, and farmers´ values and opinions related to organic agriculture are examined . Finally, a comparative analysis between the strategies used by the farmers included in the study and the components of the alternative and conventional paradigms as described by Beus and Dunlap (1990) is presented.

Réalisé dans le cadre du Programme de recherche urbaine pour le développement (PRUD); International audience; Peut-on parler d'un "modèle vietnamien" de ville asiatique ? A la différence de ce que l'on observe en Chine, il semblerait que la "transition urbaine" au Viêt-nam s'opère de façon moins radicale ou brutale. La capacité d'assimiler des modèles exogènes, la recherche d'une troisième voie entre dirigisme et libéralisme, la prise en compte du patrimoine architectural dans la planification urbaine sont autant de raisons de cette spécificité. Cet ouvrage, par le contenu de ses différents chapitres, et par les propositions de recherche formulées par ses auteurs, devrait être l'un des catalyseurs de la recherche urbaine sur le Viêt-nam.