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991.
For many years the introduction of Electronic Health Records (EHRs) in medical practice has been considered the best way to
provide efficient document sharing among different organizational settings. The actual results of these technologies, though,
do not seem to have matched expectations. The issue of document sharing has been lately readdressed by proposing the creation
of patient-controlled information and communication technologies, Personal Health Records (PHRs), providing laypeople the
tools to access, manage and share their health information electronically by connecting to the existing EHRs and other institutional
information systems. In this scenario, patients are called to play a major role in coordinating healthcare professionals by
providing them the information they need. From a CSCW perspective the PHR offers an interesting case to reflect on cooperative
work that requires new infrastructures that intersect organizational settings and extend into domestic environments. So far
though, there has not been enough research to shed light on the self-care activities carried out in the households and how
these integrate with the organizational practices of doctors and institutions. Our analyses show that health record keeping
is an articulation work necessary for meetings with doctors to proceed smoothly. To do so, people integrate the information
contained in medical documents by working on them with annotations, underlinings and integrations. Moreover, we show that
health record keeping is a spatialized activity that is inextricably interwoven with the everyday routine and objects. Finally,
we provide a tentative classification of three different strategies laypeople use to sort out health records: minimum effort,
adaptive, networking. 相似文献
992.
Maria M Velencoso Agustin SB Gonzalez Joaquin C García‐Martínez Maria J Ramos Antonio De Lucas Juan F Rodriguez 《Polymer International》2013,62(5):783-790
A simple strategy for the synthesis and functionalization of polyurethanes is described. Anionic ring‐opening polymerization was combined with ‘click’ chemistry to synthesize polyols with fluorescent properties. This route allows the incorporation of a wide range of functionalities in the polyols with an easy, clean and highly selective process compatible with several types of functional groups. The proposed strategy opens the way to the production, in a cost‐effective way, of ‘smart’ polyurethanes with non‐conventional properties like fire retardancy, antimite properties, antibacterial properties, etc. Alkynyl groups were introduced into the polyol chains by the controlled addition of glycidyl propargyl ether as co‐monomer during a conventional anionic ring‐opening copolymerization with propylene oxide. Subsequently 4‐azidomethyl‐7‐methoxycoumarin molecules were introduced onto the alkynyl‐polyether polyols by copper‐catalysed cycloaddition reactions to produce end‐functionalized polyols. The chemical structure of the novel polyols was characterized using infrared spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography with triple detection and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectroscopy. These characterization techniques confirmed the presence of a considerable amount of functional groups in the structure of the polyols. Finally, various fluorescent rigid foams, based on the functionalized polyols, were synthesized. Copyright © 2012 Society of Chemical Industry 相似文献
993.
Feng Luan Xuan Xu Huitao Liu Maria Natália Dias Soeiro Cordeiro 《Coloration Technology》2013,129(3):173-186
Dyes have been applied and are playing an increasingly important role in many industries, including the textile, printing, medical and energy industries. Their wide applications imply that specific dyes possessing given properties need to be effectively designed. The present review aims to survey information related to activity/property research of dyes that has been published in the past two decades. Emphasis is laid particularly on studies based on quantitative structure–activity/property relationships that have contributed to the theoretical design and application of dyes. Finally, the perspectives of quantitative structure‐activity/property relationship studies are set out in order to show how this method may be used to design new dyes and to evaluate their different properties. The challenges facing these studies are also outlined. 相似文献
994.
Márcia Campos Brasil Annelise Engel Gerbase Maria Augusta de Luca José Ribeiro Gregório 《Journal of the American Oil Chemists' Society》2007,84(3):289-295
Hybrid organic–inorganic films were prepared using four different hydroxylated soybean oils (HSO) or epoxidized soybean oil
as organic precursor and tetraethyl orthosilicate (TEOS) as inorganic precursor in a mass ratio of HSO:TEOS of 90:10. The
films were macroscopically homogeneous and were characterized by swelling and extraction in solvent, thermogravimetric analysis
(TGA), scanning electron microscopy (SEM) including energy dispersive spectroscopy (EDX), adhesion and hardness. Their properties
varied as a function of the number of OH groups present in the HSO. The best hybrid system was HSOF198/TEOS, with an OH value
of 198 mg of KOH/g, which presents lower swelling coefficient, very good adhesion on aluminium surface and good hardness. 相似文献
995.
In this paper we show how to establish a reliable and efficient high level communication system in a randomly deployed network of sensors equipped with directional antennas. This high level communication system enables the programming of the sensor network using high level communication functionalities without the burden of taking care of their physical capacities (low range, unidirectional links, single frequency, presence of collisions, etc.). The high level communication functionalities we offer include point-to-point communication, point-to-area communication, and one-to-all communication. The basic idea to implement this system is to simulate a virtual network that emerges from the ad-hoc network using self-organization, self-discovery and collaborative methods. We also analyse the efficiency, scalability and robustness of the proposed protocols. 相似文献
996.
We present results of a numerical simulation of the thermal convection in the subsurface mushy ice layer of Europa, one of the Jupiter’s moons. Beside fluid dynamics and heat transfer within such a layer, heat conduction in the solid crustal surface and heat exchange between the two phases – mushy ice and solid crust – are included in our model in order to follow also the evolution of the phase front. 相似文献
997.
Ian W Hamley Valeria Castelletto Nágila MPS Ricardo Maria EN Pinho Colin Booth David Attwood Zhuo Yang 《Polymer International》2007,56(1):88-92
Small‐angle X‐ray scattering was used to characterise aqueous micellar gels of triblock copolymers E137S18E137, E82S9E82, E76S5E76, E62P39E62, and of two mixtures: E137S18E137 and E62P39E62 (Mix 1) and E82S9E82 and E62P39E62 (Mix 2), each 50/50 wt%. E = oxyethylene, CH2CH2O; S = oxyphenylethylene, OCH2CH(C6H5); and P = oxypropylene, OCH2CH(CH3). Within the concentration and temperature ranges investigated (30–40 wt% copolymer, 20–80 °C), spherical micelles of copolymers E137S18E137, E82S9E82 and E62P39E62 packed into body‐centred cubic (BCC) structures. Gels of E76S5E76 were stable only at high concentrations and low temperatures, and a 70 wt% copolymer solution at T = 30 °C formed a hexagonal gel consistent with cylindrical micelles. It is likely that the mixed copolymers would form two distributions of micelles, and more complex structures were expected. However, gels of Mix 2 had well‐ordered BCC structures, while the less ordered gels of Mix 1 were also best characterised as BCC. Copyright © 2006 Society of Chemical Industry 相似文献
998.
A highly efficient Suzuki cross-coupling reaction between phenyl bromide and phenylboronic acid catalyzed by the palladium complex Pd[tBuNH(S)NHP(O)(OiPr)2-S]2Cl2 in acetonitrile, toluene, THF or DMF has been investigated. The bases we have employed for this reaction were Na2CO3, K2CO3 or Cs2CO3. It was established that using DMF and K2CO3 at 100 °C shows excellent yields of the product at the catalyst amount of 0.1 mmol. The cross-coupling reactions of iodo- and chloro-benzene with phenylboronic acid were also investigated. The influence of the halide nature was as expected. 相似文献
999.
Oliver Klein Maria Minguet Bonvehi Francisco Aguilar-Parrilla Nadine Jagerovic José Elguero Hans-Heinrich Limbach 《Israel journal of chemistry》1999,39(3-4):291-299
Using dynamic solid state 15N CPMAS NMR spectroscopy (CP ≡ cross polarization, MAS ≡ magic-angle spinning), the kinetics of degenerate intermolecular triple proton and deuteron transfers in the cyclic trimers of 15N-labeled polycrystalline 4-nitropyrazole (4NO2P) and 4-bromopyrazole (4BrP) have been studied as a function of temperature and are compared to the kinetics of triple proton transfer in bulk solid 3,5-dimethylpyrazole (DMP) studied previously. The results show that the transfer kinetics in the new trimers are much faster than in DMP. However, the kinetic HHH/HHD/HDD/DDD isotope effects of 4NO2P are similar to those of DMP. These effects indicate a single barrier for the triple proton transfers where all three protons lose zero-point energy in the transition state, as expected for a structure with three compressed hydrogen bonds. At low temperatures, strong deviations from an Arrhenius-behavior are observed which are described in terms of a modified Bell tunneling model and a concerted proton motion. The barrier for the triple proton transfer in 4NO2P and 4BrP is substantially smaller than in DMP. As there is no correlation with the electronic properties of the substituents, we assign this finding to steric effects where the bulky methyl groups of DMP in the 3- and 5-positions hinder the hydrogen bond compression, in contrast to 4NO2P and 4BrP exhibiting substitutents in the 4-position. These results lead to a minimum energy pathway of the proton transfer following in the absence of steric hindering the hydrogen bond correlation line q1 = f(q2), established previously, where q1 represents the deviation of the proton from the hydrogen bond center and q2 the N…N distance. Tunneling occurs at constant N…N distances. 相似文献
1000.
Jewgenij Botaschanjan Manfred Broy Alexander Gruler Alexander Harhurin Steffen Knapp Leonid Kof Wolfgang Paul Maria Spichkova 《Formal Aspects of Computing》2008,20(6):637-662
Formal verification of software systems is a challenge that is particularly important in the area of safety-critical automotive systems. Here, approaches like direct code verification are far too complicated, unless the verification is restricted to small textbook examples. Furthermore, the verification of application logic is of limited use in industrial context, unless the underlying operating system and the hardware are verified, too. This paper introduces a generic model stack, allowing the verification of all system layers as well as the concrete application models being used in the upper layers. The presented models and proofs close the gap between the correctness proof for the lower layers of car electronics developed at the Saarland University and the verification procedure for distributed applications developed at the Technische Universität München. 相似文献