3,857 research outputs found
Cholesteric Liquid Crystalline Copolymers for Gas Chromatographic Separation of Polycyclic Aromatic Compounds
A novel series of side-chain liquid crystalline copolysiloxanes containing [S]-1-(2-naphthyl) ethyl 6-[4-(10-undecen-1-yloxy) biphenyl--carbonyloxy]-2-naphthoate mesogenic and 4-biphenyl -allyloxybenzoate mesogenic side groups in the backbone and side chains liquid crystalline copolymers were prepared and evaluated as possible stationary phases for gas chromatography capillary columns. All copolymers display enantiotropic cholesteric phases. These mesomorphic polysiloxanes specimens with the widest temperature range were used as the stationary phase in a gas chromatography capillary column, and it showed good thermal and physical stability, excellent chemical inertness, and unique separation properties for polycyclic aromatic compounds. These cholesteric LC copolysiloxane stationary phases show much better separation effect for the polycyclic aromatic compound than those of the nematic and smectic LC copolysiloxanes
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Significance, Opportunities and Challenges of Cultural Landscape Conservation and Bhutan Heritage Bill – UNESCO’s Experiences of Bhutan
UNESCO was the first United Nations agency to deal with landscapes at a global scale, notably through the 1962 UNESCO Recommendation on the Beauty and Character of Landscapes and Sites and the 1972 Convention Concerning the Protection of the World Cultural and Natural Heritage. This article shares the knowledge and experience garnered by UNESCO through its conservation and management activities at Cultural Landscapes in Bhutan and highlights the urgent need for a cultural-historical-natural territory approach to address the pressing challenges for the conservation of Cultural Landscapes in Bhutan, and for a strong focus on the peoples and communities that inhabit these territories and their involvement at all stages.
Since long, Bhutan is regarded as a most mysterious and remote country, hidden in the Himalayas. A complex cultural landscape has evolved in the small nation of Bhutan for millennia. However, recently, Bhutan is considered to be one of the most rapidly urbanizing societies in Asia, and people in Bhutan have expressed worry about these changes. Acknowledging that Bhutan is a rare case where almost the entire land has retained a magnificent landscape displaying a harmonious co-existence of culture and nature, the UNESCO World Heritage Centre is providing technical assistance to the Government of Bhutan to make Cultural Landscapes a focus of heritage protection in the country’s administrative framework, the national policy, good practice as well as the very first Bhutan Heritage Bill.
A series of the Five UNESCO-Bhutan Support Cultural Landscape Initiatives workshops, including panel sessions and forums, set up a platform since 2014 to introduce ‘cultural landscape’ as a new conservation concept, along with conserving and raising awareness of its cultural landscapes to gain attention of multiple stakeholders, such as of town planning, agricultural development and tourism. The cultural-historical-natural territory approach and communities involvement for Cultural Landscape conservation and management has been presented in order to develop a common vision to sustain the values of cultural landscape, which would be an important indicator of the success of the Bhutanese Gross National Happiness. It is very promising to note that in the draft Heritage Bill of Bhutan (now under final Governmental adoption), the entire country is defined as a Cultural Landscape from the Preamble onwards: ‘Bhutan’s uniqueness lies in its cultural landscape where tangible and intangible cultural heritage and nature coexist harmoniously’.
Français :
L\u27UNESCO a été la première agence des Nations Unies à s\u27occuper des paysages à l\u27échelle mondiale, notamment à travers la Recommandation de l\u27UNESCO de 1962 sur la beauté et le caractère des paysages et des sites et la Convention de 1972 concernant la protection du patrimoine mondial, culturel et naturel. Cet article partage les connaissances et l\u27expérience acquises par l\u27UNESCO à travers ses activités de conservation et de gestion des paysages culturels au Bhoutan et souligne le besoin urgent d\u27une approche culturelle, historique et naturelle des territoires pour relever les défis urgents de la conservation des paysages culturels au Bhoutan, et pour une forte focalisation sur les peuples et les communautés qui habitent ces territoires et leur implication à toutes les étapes.
Depuis longtemps, le Bhoutan est considéré comme un pays des plus mystérieux et reculé, caché dans l\u27Himalaya. Un paysage culturel complexe a évolué dans la petite nation du Bhoutan pendant des millénaires. Cependant, récemment, le Bhoutan est considéré comme l\u27une des sociétés d\u27Asie qui s\u27urbanise le plus rapidement, et les Bhoutanais ont exprimé leur inquiétude face à ces changements. Reconnaissant que le Bhoutan est un cas rare où presque tout le territoire a conservé un paysage magnifique affichant une coexistence harmonieuse de la culture et de la nature, le Centre du patrimoine mondial de l\u27UNESCO fournit une assistance technique au gouvernement du Bhoutan pour faire des paysages culturels un centre de patrimoine protection dans le cadre administratif du pays, la politique nationale, les bonnes pratiques ainsi que le tout premier projet de loi sur le patrimoine du Bhoutan.
Une série de cinq ateliers UNESCO-Bhutan Support Cultural Landscape Initiatives, y compris des panels et des forums, a mis en place une plate-forme depuis 2014 pour présenter le « paysage culturel » en tant que nouveau concept de conservation, ainsi que la conservation et la sensibilisation à ses paysages culturels pour gagner l\u27attention de multiples acteurs, tels que l\u27urbanisme, le développement agricole et le tourisme. L\u27approche du territoire culturel, historique et naturel et l\u27implication des communautés pour la conservation et la gestion du paysage culturel ont été présentées afin de développer une vision commune pour soutenir les valeurs du paysage culturel, ce qui serait un indicateur important du succès du bonheur national brut du Bhoutan. . Il est très prometteur de noter que dans le projet de loi sur le patrimoine du Bhoutan (maintenant en cours d\u27adoption finale par le gouvernement), le pays tout entier est défini comme un paysage culturel à partir du préambule : « Le caractère unique du Bhoutan réside dans son paysage culturel où le patrimoine culturel matériel et immatériel et la nature coexistent harmonieusement ».
Español:
La UNESCO fue el primer organismo de las Naciones Unidas que se ocupó de los paisajes a escala mundial, en particular a través de la Recomendación de la UNESCO de 1962 sobre la belleza y el carácter de los paisajes y sitios y la Convención de 1972 sobre la protección del patrimonio mundial cultural y natural. Este artículo comparte el conocimiento y la experiencia acumulados por la UNESCO a través de sus actividades de conservación y gestión en los paisajes culturales en Bután y destaca la necesidad urgente de un enfoque cultural-histórico-territorial natural para abordar los desafíos urgentes para la conservación de los paisajes culturales en Bután, y por un fuerte enfoque en los pueblos y comunidades que habitan estos territorios y su participación en todas las etapas.
Desde hace mucho tiempo, Bután es considerado un país muy misterioso y remoto, escondido en el Himalaya. Un paisaje cultural complejo ha evolucionado en la pequeña nación de Bután durante milenios. Sin embargo, recientemente, se considera que Bután es una de las sociedades que se urbanizan más rápidamente en Asia, y la gente de Bután ha expresado su preocupación por estos cambios. Reconociendo que Bután es un caso raro en el que casi toda la tierra ha conservado un paisaje magnífico que muestra una coexistencia armoniosa de cultura y naturaleza, el Centro del Patrimonio Mundial de la UNESCO está brindando asistencia técnica al Gobierno de Bután para hacer de los Paisajes Culturales un foco de patrimonio. protección en el marco administrativo del país, la política nacional, las buenas prácticas y el primer proyecto de ley del patrimonio de Bhután.
Una serie de talleres de las cinco iniciativas de apoyo al paisaje cultural de la UNESCO-Bután, que incluyen sesiones de panel y foros, estableció una plataforma desde 2014 para presentar el `` paisaje cultural \u27\u27 como un nuevo concepto de conservación, junto con la conservación y la concienciación de sus paisajes culturales para ganar atención de múltiples actores, como el urbanismo, el desarrollo agrícola y el turismo. El enfoque cultural-histórico-territorial natural y la participación de las comunidades para la conservación y gestión del paisaje cultural se han presentado con el fin de desarrollar una visión común para sostener los valores del paisaje cultural, que sería un indicador importante del éxito de la Felicidad Nacional Bruta de Bután. . Es muy prometedor observar que en el proyecto de Ley del Patrimonio de Bután (ahora en proceso de aprobación gubernamental final), todo el país se define como un paisaje cultural desde el Preámbulo en adelante: \u27La singularidad de Bután radica en su paisaje cultural donde el patrimonio cultural tangible e intangible y la naturaleza conviven armoniosamente ”
Systematic {\em ab initio} study of the phase diagram of epitaxially strained SrTiO
We use density-functional theory with the local-density approximation to
study the structural and ferroelectric properties of SrTiO under misfit
strains. Both the antiferrodistortive (AFD) and ferroelectric (FE)
instabilities are considered. The rotation of the oxygen octahedra and the
movement of the atoms are fully relaxed within the constraint of a fixed
in-plane lattice constant. We find a rich misfit strain-induced phase
transition sequence and is obtained only when the AFD distortion is taken into
account. We also find that compressive misfit strains induce ferroelectricity
in the tetragonal low temperature phase only whilst tensile strains induce
ferroelectricity in the orthorhombic phases only. The calculated FE
polarization for both the tetragonal and orthorhombic phases increases
monotonically with the magnitude of the strains. The AFD rotation angle of the
oxygen octahedra in the tetragonal phase increases dramatically as the misfit
strain goes from the tensile to compressive strain region whilst it decreases
slightly in the orthorhombic (FO4) phase. This reveals why the polarization in
the epitaxially strained SrTiO would be larger when the tensile strain is
applied, since the AFD distortion is found to reduce the FE instability and
even to completely suppress it in the small strain region. Finally, our
analysis of the average polar distortion and the charge density distribution
suggests that both the Ti-O and Sr-O layers contribute significantly to the FE
polarization
From Isovist to Spatial Perception: Wayfinding in Historic Quarter
Based on the assumption that human behaviours are mainly affected by physical and animate environments, this empirical research takes the changeful and complex historical district in Tainan to observe wayfinding behaviours. An a priori analysis of the isovist fields is conducted to identify spatial characteristics. Three measures, the relative area, convexity, and circularity, are applied to scrutinize the possible stopping points, change of speed, and route choices. Accordingly, an experiment is carried out to observe spatial behaviours and different influences of social stimuli. Results show that social interactions afford groups and pairs to perform better than individual observers in wayfinding.© 2016. The Authors. Published for AMER ABRA by e-International Publishing House, Ltd., UK. This is an open access article under the CC BY-NC-ND license (http://creative commons.org/licenses/by-nc-nd/4.0/).Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.Keywords: wayfinding; isovist; spatial perception and social stimuli; historic quarte
The Relationships among Buyers’ Perceived Risk, Exhibitors’ Brand Equity, Purchase Postponement and Switching Intention-From the Perspectives of Perceived Risk Theory and Expectancy Theory
This study explores the effects of buyers’ perceived risk on their purchase postponement and switching intention in an international industrial fair, as well as examines the moderating effect of exhibitors’ brand equity on the above relationships. This study uses the purposive sampling method to survey buyers of the famous International Woodworking Machine Fair in Hanover, Germany. Of the 200 surveys distributed, 105 valid questionnaires were returned, representing a response rate of 52.50%. Analytical results show that higher buyers’ perceived risk is associated with buyers’ higher purchase postponement, and stronger switching intention. Furthermore, when facing high-brand equity exhibitors’ products, if buyers perceive low risk of use, they are unlikely to delay purchase and switch suppliers; in contrast, if they perceive high risk of use, they are more likely to delay purchase and switch suppliers. Finally, when buyers face low-brand equity exhibitors’ products, if they perceive low risk of use, they will delay purchase and switch suppliers; in contrast, if they perceive high risk of use, they will tend not to delay purchase and switch suppliers
Decomposition of the complete bipartite graph with a 1-factor removed into paths and stars
Let P_k denote a path on k vertices, and let S_k denote a star with k edges. For graphs F, G, and H, a decomposition of F is a set of edge-disjoint subgraphs of F whose union is F. A (G,H)-decomposition of F is a decomposition of F into copies of G and H using at least one of each. In this paper, necessary and sufficient conditions for the existence of the (P_{k+1},S_k)-decomposition of the complete bipartite graph with a 1-factor removed are given
Camptothecin-Loaded Liposomes with α-Melanocyte-Stimulating Hormone Enhance Cytotoxicity Toward and Cellular Uptake by Melanomas: An Application of Nanomedicine on Natural Product
ABSTRACTIn this study, we attempted to develop functional liposomes loaded with camptothecin and attached to α-melanocyte-stimulating hormone (α-MSH) to target melanoma cells. The liposomes were mainly composed of phosphatidylcholine, cholesterol, and stearylamine, and were characterized by the vesicle size, zeta potential, camptothecin encapsulation efficiency, and release behavior. Results revealed that α-MSH liposomes possessed an average size of approximately 250nm with a surface charge of 60mV. Camptothecin was successfully entrapped by the targeted liposomes with an encapsulation percentage of nearly 95%. The liposomes provided sustained and controlled camptothecin release. Non-targeted liposomes with the drug exerted superior cytotoxicity against melanomas compared to the free control. Cell viability was reduced from 48% to 32% compared to conventional liposomes. Peptide ligand conjugation further promoted cytotoxicity to 18% viability, which was a 2.7-fold decrease versus the free control. According to the images of fluorescence microscopy, α-MSH liposomes exhibited greater cell endocytosis than did non-targeted liposomes and the free control. α-MSH liposomes were predominantly internalized in the cytoplasm. These findings demonstrate that α-MSH liposomes could enhance the anti-melanoma activity of camptothecin owing to their targeting ability and controlled drug delivery
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