Search results for "scot"
showing 10 items of 194 documents
The Effect of Central Vision Loss on Perception of Mutual Gaze
2014
People with central vision loss (CVL) often report difficulties with social interactions and reduced social functioning.1, 2 A limited access to the nonverbal visual cues inherent to effective communication can be a disadvantage in social interactions. Wang and Boerner3 reported that for people with vision impairment, difficulty in social situations was due either to the individual’s own lack of ability to perceive visual cues or other people’s lack of understanding. The facial region has been noted as an important source of nonverbal visual information relevant to social situations.4 Prior studies of individuals with CVL due to age-related macular degeneration have focused primarily on dif…
Clinical magnification and residual refraction after implantation of a double intraocular lens system in patients with macular degeneration
2007
Purpose To evaluate the efficacy of a standard double intraocular lens (IOL) system (IOL-Vip) in patients with low vision and central scotoma due to macular degeneration and assess the predictability of the residual refraction and magnification. Setting Ophthalmology Department, Hospital General Universitario, Valencia, Spain. Methods This interventional prospective noncomparative case series comprised 13 consecutive surgical procedures in 10 patients with central scotoma. Follow-up was 12 months. Evaluation included the difference between preoperative and postoperative best corrected visual acuity (BCVA), refraction, position of the IOLs, endothelial cell density, and occurrence of postope…
Le storytelling dans la communication touristique d'un pays : L'exemple de l'Ecosse
2015
A travel involves money, time and imagination. It plays a significant role in the creation of the tourists’ identities. Theoretically, touristic communication consists of an organization that formulates a message and an audience, who interprets it, with different motivations but at least an interest. This enunciative relation has twists and turns: perceptions, emotions, influences affect the message and change its intended meaning. The people who advertise the destination must consider these gaps in interpretation to incite potential tourists to discover a place. There is a category of communication called “storytelling”, especially with the contribution of local people, which presents test…
Modes of Structure Formation in Doped Discotic Polymers and Low Molar Mass Model Systems
1991
By doping low molar mass or polymeric liquid crystals containing flat disc-like units with electron acceptors one achieves a stabilization of columnar phases, the induction of a columnar phases in otherwise discotic nematic or even in amorphous systems. Theoretical models based on the assumption of strong electron donator-acceptor (EDA) complex formation are able to account for the structure formation on a molecular level and the thermodynamic properties of the mixtures and the model of diffusion limited aggregation (DLA) for the structure formation on a supermolecular structure.
Transient photoconductivity in a discotic liquid crystal
1993
Using a time-of-flight technique, different transport mechanisms, deep trapping, multiple shallow trapping, and ideal itrinsic transport, can be observed in the different temperature and phase regions of the liquid-crystalline photoconductor hexapentyloxytriphenylene. The temperature and field dependences of carrier mobilities up to 1\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}3}$ ${\mathrm{cm}}^{2}$/V s have been determined; this value exceeds considerably the mobilities of the most commonly used organic photoconductors. The experiments reflect a variety of transport phenomena which are novel in the field of liquid-crystalline systems.
Electronic Properties of Discotic LC-Materials
1996
Abstract We have made extensive studies of the charge-carrier mobilities in the discotic hexagonal mesophases of triphenylene-based discotic liquid crystals. Using the time-of-flight technique, transient photocurrents were measured yielding charge-carrier mobilities for various electric fields and temperatures. Starting from promising results obtained with the monomeric discotic liquid crystalline model compound hexapentyloxytriphenylene (H5T), we synthesized a “discotic twin” with two triphenylene units linked together by a suitable spacer. Additionally, we synthesized a discotic liquid crystalline oligomer consisting of four triphenylene units which are bound to a flexible cyclosiloxane r…
Infrared absorption study of hexapentyloxytriphenylene A discotic liquid crystal
1993
Abstract Fourier transform infrared absorption (FTIR) spectroscopy has been used to study a discotic liquid crystal. IR spectra are reported as a function of temperature for hexapentyloxytriphenyle...
Fluoroalkylated discotic liquid crystals
1995
Abstract The concept of mesophase stabilization by partial fluorination of side chains has been extended to discotic systems. The mesophase structure is essentially unchanged, whereas the temperature range of the mesophase is strongly affected by the fluorinated side chains. Triphenylene substituted with only one partially fluorinated side chain exhibits a decrease of the clearing temperature, whereas for symmetrically substituted systems a broad range mesophase has been observed. This behaviour can be attributed to a segregation of the incompatible parts of the molecule giving rise to a stabilized columnar structure for the symmetrical substitution pattern.
Monolayers and Langmuir-Blodgett Multilayers of Discotic Liquid Crystals?
2008
The field of monolayer and multilayer films of discotic LCs is at its very beginning. The scope and limitations of this preparation method have not yet been explored, and little is known about the structures obtainable. However, the potential access to extraordinary, ordered thin films is fascinating, and will stimulate research in the future.
Tetrakis(oxadiazolylphenyl)pyrazines: New St. Andrew's Cross-Shaped Liquid Crystals.
2019
π-Conjugated molecules with the shape of St. Andrew's cross have been synthesized via fourfold Huisgen reaction. Four 2,5-diaryl-1,3,4-oxadiazol arms are attached to a central pyrazine nucleus. These fluorescent stars, when decorated with a rim of eight alkoxy side chains are discotic liquid crystals. Depending on the substitution pattern, the width of the liquid phase varies within a broad range of 25 °C to 250 °C. In their liquid crystalline phase, the molecules assemble in a typical hexagonal columnar supramolecular arrangement.