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11.
N Kates M Craven AM Crustolo L Nikolaou C Allen 《Canadian Metallurgical Quarterly》1997,19(5):324-332
The increasingly prominent role of the family physician in delivering mental health care can be enhanced if productive and collaborative relationships can be established with local mental health services. This paper describes a Canadian program that has achieved this by bringing mental health counselors and psychiatrists into the offices of 87 family physicians in 35 practices in a community in Southern Ontario. The paper describes the program, the activities of counselors and psychiatrists within the practices, and the administrative structures set up to coordinate these activities. Data is presented from the evaluation of the first year of the program's operation (13 practices and 45 family physicians) during which time 3085 referrals were received. The program made mental health care more available and accessible, increased continuity of care, provided additional support for the family physician, offered new opportunities for continuing education, and led to a reduced and more efficient use of other mental health services. The components of the program can be adapted to most communities. 相似文献
12.
Cooling breakdown in highly exothermic reaction processes may lead to runaway. The sensitivity and the safety assessment of a batch process on cooling breakdown are studied. The dependence of the minimum cooling time and the maximum allowable time of cooling breakdown for safe operation on the process parameters is investigated. 相似文献
13.
Jose R. Rios Viqueira Nikos A. Lorentzos 《The VLDB Journal The International Journal on Very Large Data Bases》2007,16(2):179-200
An SQL extension is formalized for the management of spatio-temporal data, i.e. of spatial data that evolves with respect
to time. The extension is dedicated to applications such as topography, cartography, and cadastral systems, hence it considers
discrete changes both in space and in time. It is based on the rigid formalization of data types and of SQL constructs. Data types are defined in terms of time and
spatial quanta. The SQL constructs are defined in terms of a kernel of few relational algebra operations, composed of the well-known operations of the 1NF model and of two more, Unfold and Fold. In conjunction with previous work, it enables the uniform management of 1NF structures that may contain not only spatio-temporal
but also either purely temporal or purely spatial or conventional data. The syntax and semantics of the extension is fully
consistent with the {SQL:2003} standard. 相似文献
14.
Nikos K. Flevaris 《Journal of Materials Science》1989,24(1):313-320
Systems with a coherently modulated composition are considered with regard to their elastic properties. The (stress-free) coherency strains are considered in a new frame where the standard state is redefined on the basis of the property under study. These strains are used in the study of the thermodynamics of spinodal decomposition in solids with a (generally) anisotropic distortion into a cubic matrix. Finally, the influence of these strains is considered in the study of magnetostrictive effects in such modulated systems or strained-layer superlattices. 相似文献
15.
Summary Intrinsic viscosities [] in tetrahydrofuran (THF) at 30°C are reported for ten narrow molecular weight distribution poly(methyl methacrylate) (PMMA) samples covering nearly two orders of magnitude in molecular weight. By combining the viscosity results with absolute weight-average molecular weights
determined via low-angle laser light scattering (LALLS) experiments, we have accurately determined the Mark-Houwink-Sakurada (MHS) parameters for this polymer-solvent pair (K=7.56x105 and a=0.731, when [] is in dL g-1). 相似文献
16.
Häfliger P Agorastos N Spingler B Georgiev O Viola G Alberto R 《Chembiochem : a European journal of chemical biology》2005,6(2):414-421
The potential of certain Auger electron emitting nuclides for systemic radiotherapeutic applications has recently gained much attention. In particular, the ability of several nuclides, including 111In, 125I, and 123I, to induce DNA double-strand breaks (dsb), a good indicator of cytotoxicity, has been extensively studied. However, this ability has never previously been shown experimentally for 99mTc, which, besides the well-known gamma radiation that is used for diagnostic applications, also emits an average of 1.1 conversion electrons and 4 Auger or Coster-Kronig electrons per decay. Owing to the short range of Auger electrons, the radionuclide needs to be located very close to the DNA for dsb to occur. We synthesized two cationic 99mTcI-tricarbonyl complexes with pendant DNA binders, pyrene and anthraquinone. The X-ray crystal structures of the two complexes could be elucidated. Linear dichroism and UV/Vis spectroscopy revealed that the complex with pyrene intercalates DNA with a stability constant, K, of 1.1 x 10(6) M(-1), while the analogous complex with anthraquinone interacts with DNA in a groove-binding mode and has an affinity value of K=8.9 x 10(4) M(-1). We showed with phiX174 double-stranded DNA that the corresponding 99mTc complexes induce a significant amount of dsb, whereas non-DNA-binding [TcO4]- and nonradioactive Re compounds did not. These results indicate that the Auger electron emitter 99mTc can induce dsb in DNA when decaying in its direct vicinity and this implies potential for systemic radiotherapy with 99mTc complexes. 相似文献
17.
Nikos Mavrogiannopoulos Andreas Pashalidis Bart Preneel 《International Journal of Information Security》2014,13(3):217-228
Public key Kerberos (PKINIT) is a standard authentication and key establishment protocol. Unfortunately, it suffers from a security flaw when combined with smart cards. In particular, temporary access to a user’s card enables an adversary to impersonate that user for an indefinite period of time, even after the adversary’s access to the card is revoked. In this paper, we extend Shoup’s key exchange security model to the smart card setting and examine PKINIT in this model. Using this formalization, we show that PKINIT is indeed flawed, propose a fix, and provide a proof that this fix leads to a secure protocol. 相似文献
18.
Nikos K. Kalfoglou 《应用聚合物科学杂志》1986,32(6):5247-5259
The effects of carbon black, talc, and ultrafine silica filler, at different filler, loading, on the compatibility of two binary blends was examined. These were, the mechanically compatible polyurethane (PU)/poly(vinyl chloride) (PVC) at 25/75 weight ratio, and the poly(ε-caprolactone) (PCL)/styrene–acylonitrile (SAN) copolymer (with 30% AN content), at the 50/50 blend composition. For the former system, both dynamic mechanical analysis (DMA) and DSC measurements indicated that, depending on the filler surface, boundary layers are formed at the filler–matrix interface shifting the PU relaxation to higher temperatures. No significant effect was observed for the PVC component. Though the mechanical spectra are also affected, essentially no Tg shifts were observed for the PCL–SAN system. A qualitative explanation of selective filler activity towards the blend components was given by invoking the matrix–filler basic–acidic nature. Overall, the fillers had no compatibilizing effect on the blend. Using available theory both DSC and the DMA techniques agree in their estimate of the boundary layer thickness. Moduli data were also analyzed using mechanics models proposed for composite systems. 相似文献
19.
Albert Angel Nick Koudas Nikos Sarkas Divesh Srivastava Michael Svendsen Srikanta Tirthapura 《The VLDB Journal The International Journal on Very Large Data Bases》2014,23(2):175-199
Recent years have witnessed an unprecedented proliferation of social media. People around the globe author, everyday, millions of blog posts, social network status updates, etc. This rich stream of information can be used to identify, on an ongoing basis, emerging stories, and events that capture popular attention. Stories can be identified via groups of tightly coupled real-world entities, namely the people, locations, products, etc, that are involved in the story. The sheer scale and rapid evolution of the data involved necessitate highly efficient techniques for identifying important stories at every point of time. The main challenge in real-time story identification is the maintenance of dense subgraphs (corresponding to groups of tightly coupled entities) under streaming edge weight updates (resulting from a stream of user-generated content). This is the first work to study the efficient maintenance of dense subgraphs under such streaming edge weight updates. For a wide range of definitions of density, we derive theoretical results regarding the magnitude of change that a single edge weight update can cause. Based on these, we propose a novel algorithm, DynDens, which outperforms adaptations of existing techniques to this setting and yields meaningful, intuitive results. Our approach is validated by a thorough experimental evaluation on large-scale real and synthetic datasets. 相似文献