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Original State (original + state)
Selected AbstractsJohn Whitehurst (1713,1788): philosopher, geologist, horologist and engineerGEOLOGY TODAY, Issue 3 2002Trevor D. Ford Among the late 18th-century pioneers of geological science was John Whitehurst. He set the scene for the early Derbyshire geologists, White Watson and John Farey, whose books were not published until 1811, long after Whitehurst's death. But Whitehurst's ideas went beyond Derbyshire; he looked at the global situation in his book An Inquiry into the Original State & Formation of the Earth (1778, 1786). Whitehurst was a founder member of the influential Lunar Society and a close friend of many philosophers of the period. [source] Effect of Cog Threads under Rat SkinDERMATOLOGIC SURGERY, Issue 12 2005Hyo Jook Jang MD Background. The aging face loses the tensile strength of structural integrity. Cog threads have been used recently to tighten lax skin and soft tissue. Objective. A comparative study of the effects of cog, monofilament, and multifilament threads under rat skin. Methods. Each cog, monofilament, and multifilament thread was inserted under the facial skin of a cadaver and the panniculus carnosus of rat dorsal skin. The maximum holding strength (MHS) of the thread and the tearing strength of the skin around the thread were measured with a tensiometer. The thickness of the capsule around the thread and the myofibroblasts was observed histologically. Results. In the cadaver, the MHS of the cog thread was 190.7 ± 65.6 g. It was greater than that of the monofilament (22.4 ± 7.7 g) or multifilament (40.4 ± 19.7 g) thread. In the rat, the MHS of the cog thread was 95.1 ± 18.8 g. It was greater than that of the monofilament (4.3 ± 1.3 g) or multifilament (10.9 ± 2.1 g) thread in the second week. The thickness of the capsule around the cog thread was 93.0 ± 3.2 ,m. It was thicker than the monofilament thread's capsule, 39.2 ± 12.1 ,m, in the fourth week. The number of myofibroblasts presented significantly more in the cog (96.0 ± 72.4) than in the monofilament thread (4.3 ± 4.4). The rumpled in-between skin suspended by each of the three different threads returned to its original state in 2 weeks. Conclusion. The cog thread placed under the rat skin immediately pulled the skin and subcutaneous tissue. The myofibroblasts around the thread played a role in fibrous tissue contracture 4 weeks postinsertion of the thread. These findings could be the basis for clinical application. THIS STUDY WAS SUPPORTED BY A GRANT FROM THE KOREA HEALTH 21 R&D PROJECT, MINISTRY OF HEALTH AND WELFARE, REPUBLIC OF KOREA. [source] Electrochemical Sensing of Thiocyanate Using Gold Electrodes Modified with an Underpotentially Deposited Silver MonolayerELECTROANALYSIS, Issue 2 2010Christopher Abstract Gold electrodes modified by underpotential deposition to expose a layer of silver atoms on their surfaces were used to measure thiocyanate concentrations in aqueous solutions. When exposed to thiocyanate, the ion adsorbs onto the modified electrode and causes changes in the electrochemical properties of the silver adlayer. Coulometric measurement of the fraction of the silver adlayer that remains in its original state provides a means for determining thiocyanate concentrations. The adsorption of thiocyanate onto the electrode follows a first-order process with a rate constant of ca. 440,L/mol s that defines its concentration/time response. [source] Microscopic description of information transfer from a qudit to reservoirFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 4-5 2003telmachovi Recently Ziman et al. [3] have introduced a concept of a universal quantum homogenizer which is a quantum machine that takes as an input a system qubit initially in an arbitrary state , and a set of N reservoir qubits initially prepared in the same state ,. The homogenizer realizes, in the limit sense, the transformation such that at the output each qubit is in an arbitrarily small neighbourhood of the state , irrespective of the initial states of the system and the reservoir qubits. In this paper we generalize the concept of quantum homogenization for qudits, that is, for d -dimensional quantum systems. We prove that the partial swap operation induces a contractive map with the fixed point which is the original state of the reservoir. Finally we propose an optical realization of the quantum homogenization. [source] Photochromic Polymers Based on the Photoinduced Opening and Thermal Closing of [1,3]Oxazine RingsADVANCED FUNCTIONAL MATERIALS, Issue 24 2009Massimiliano Tomasulo Abstract Two macromolecular constructs incorporating a single polymer backbone with multiple photochromic side chains are developed. Both systems are prepared from preformed photochromic [1,3]oxazines after the ring-opening polymerization of their norbornene appendages. In solution, UV illumination of these polymers opens the [1,3]oxazine rings in their side chains in less than 6,ns and with a quantum yield of 0.09 in both instances. The photogenerated species incorporate a 4-nitrophenolate chromophore, and hence, their formation is accompanied by the appearance of an intense band in the visible region of the absorption spectrum. The photoproducts revert spontaneously to the original state with first-order kinetics in microseconds. Furthermore, both photochromic polymers tolerate hundreds of switching cycles with no sign of degradation, even in the presence of molecular oxygen. Thus, this design logic and choice of functional building blocks can translate into the realization of innovative photoresponsive materials with excellent photochromic performance. [source] Reversibly Deformable and Mechanically Tunable Fluidic AntennasADVANCED FUNCTIONAL MATERIALS, Issue 22 2009Ju-Hee So Abstract This paper describes the fabrication and characterization of fluidic dipole antennas that are reconfigurable, reversibly deformable, and mechanically tunable. The antennas consist of a fluid metal alloy injected into microfluidic channels comprising a silicone elastomer. By employing soft lithographic, rapid prototyping methods, the fluidic antennas are easier to fabricate than conventional copper antennas. The fluidic dipole radiates with ,90% efficiency over a broad frequency range (1910,1990,MHz), which is equivalent to the expected efficiency for a similar dipole with solid metallic elements such as copper. The metal, eutectic gallium indium (EGaIn), is a low-viscosity liquid at room temperature and possesses a thin oxide skin that provides mechanical stability to the fluid within the elastomeric channels. Because the conductive element of the antenna is a fluid, the mechanical properties and shape of the antenna are defined by the elastomeric channels, which are composed of polydimethylsiloxane (PDMS). The antennas can withstand mechanical deformation (stretching, bending, rolling, and twisting) and return to their original state after removal of an applied stress. The ability of the fluid metal to flow during deformation of the PDMS ensures electrical continuity. The shape and thus, the function of the antenna, is reconfigurable. The resonant frequency can be tuned mechanically by elongating the antenna via stretching without any hysteresis during strain relaxation, and the measured resonant frequency as a function of strain shows excellent agreement (±0.1,0.3% error) with that predicted by theoretical finite element modeling. The antennas are therefore sensors of strain. The fluid metal also facilitates self-healing in response to sharp cuts through the antenna. [source] Sorption of tannic acid on zirconium pillared clayJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 1 2002P Vinod Abstract Zirconium pillared clay (PILC) was prepared using montmorillonite as the base clay. Adsorption of tannic acid (tannin) was studied by a batch equilibrium technique, as a function of adsorbate concentration, temperature, pH, agitation speed, particle size of the adsorbent and ionic strength. The process of uptake is governed by diffusion controlled first-order reversible rate kinetics. The higher uptake for the pH range 4.0,6.0 was attributed to external hydrogen bonding between phenolic-OH groups of tannin molecules and the hydrogen bonding sites on the clay. The removal of tannin by adsorption was found to be >99.0% depending on the initial concentration in the pH range of 4.0,6.0. The process involves both film and pore diffusion to different extents. The effects of solute concentration, temperature, agitation speed and particle size on the diffusion rate were investigated. Tannin uptake was found to increase with ionic strength due to the compression of diffuse double layers. The applicability of Langmuir and Freundlich isotherm models has been tested. The maximum adsorption capacity of PILC was found to be 45.8,µmol,g,1 of clay and the affinity constant is 2.9,×,10,2,dm3,µmol,1 at 30,°C. Thermodynamic parameters such as ,G,°,,H,° and ,S,° were calculated to predict the nature of adsorption. The isosteric enthalpies of adsorption were also determined and found to decrease with increasing surface coverage. Regeneration with hot water (60,°C) has been investigated for several cycles with a view to recovering the adsorbed tannin and also restoring the sorbent to its original state. Copyright © 2001 Society of Chemical Industry [source] Electronic structure of GaN(0001)-2 × 2 thin films grown by PAMBEPHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 5 2008R. Gutt Abstract Gallium nitride thin films were grown on silicon carbide (0001) by plasma-assisted molecular beam epitaxy (PAMBE). The samples were cooled down in nitrogen plasma and characterized in situ by reflection high energy electron diffraction (RHEED), photoelectron spectroscopy (XPS/UPS), and atomic force microscopy (AFM) revealing stoichiometric and smooth GaN films virtually free of contaminations. We present valence band data obtained by UPS with strong emission from surface states inside the fundamental band gap. These states and the observed 2 × 2 surface reconstruction are highly sensitive towards residual molecules. Once these surface states have disappeared the original state could not be recovered by surface preparation methods underlining the necessity of in situ investigations on as-grown surfaces. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] SAND FOR ROMAN GLASS PRODUCTION: AN EXPERIMENTAL AND PHILOLOGICAL STUDY ON SOURCE OF SUPPLY*ARCHAEOMETRY, Issue 3 2006A. SILVESTRI This paper reports the results of an experimental study performed on Campanian littoral sand, together with a careful philological analysis of Pliny's text concerning the production of glass using the above sand in order to verify its suitability. Accurate chemical and mineralogical characterization of sand samples and experimental glasses was carried out, proving the unsuitability of sand for glass production in its original state. Taking into account both the results of the philological analysis of Pliny's text and the mineralogical assemblage of the sand, a new hypothesis regarding Roman glass-making technology is proposed and tested here. The technology implies the production of ,quartz-enriched' sand by means of selective grindings according to the different degrees of hardness and cleavage of the mineralogical phases. Melting experiments, carried out on treated sand and in the temperature range compatible with Roman technology, yielded a glass with composition similar to those of typical Roman glasses. Therefore, new perspectives on the sources of supply of raw materials, hitherto debated, are opened up. [source] Behavioral change related to Wenchuan devastating earthquake in miceBIOELECTROMAGNETICS, Issue 8 2009Yonghong Li Abstract It has been suggested that some animals are much more capable of perceiving certain kinds of geophysical stimuli which may precede earthquakes than humans, but the anecdotal phenomena or stories about unusual animal behaviors prior to an earthquake should be interpreted with objective data. During the Wenchuan magnitude 8.0 earthquake that happened in Wenchuan county (31.0° north latitude, 103.4° east longitude) of Sichuan province, China, on May 12, 2008, eight mice were monitored for locomotor activity and circadian rhythm in constant darkness with temperature 22,24 °C and humidity 55,65% for 38 days. The ongoing monitoring of locomotor activity of mice in our laboratory made it possible to design a posteriori study investigating whether the earthquake was associated with any change in animal behavior. Based on analyzing the recorded data with single cosinor, we found that the locomotor activity dramatically decreased in six of these eight mice on day 3 before the earthquake, and the circadian rhythm of their locomotor activity was no longer detected. The behavioral change lasted for 6 days before the locomotor activity returned to its original state. Analyses of concurrent geomagnetic data showed a higher total intensity during the span when the circadian rhythm in locomotor activity weakened. These results indicated that the behaviors, including circadian rhythm and activity, in these mice indeed changed prior to the earthquake, and the behavioral change might be associated with a change of geomagnetic intensity. Bioelectromagnetics 30:613,620, 2009. © 2009 Wiley-Liss, Inc. [source] | |||||||||||||