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101.
102.
A review of isolates of Neisseria meningitidis and other laboratory evidence of meningococcal infection was carried out for the period 1990-1995. Thirty-three patients with evidence of meningococcal disease were identified over the six year period. Group B organisms were the most commonly identified, but an increase in Group C has occurred and is almost equal in number. Data from clinical, laboratory and public health sources should be centralized in a National Surveillance Centre.  相似文献   
103.
In the present study of gas–liquid contactors, mean residence/contact time was calculated from knowledge of superficial velocity and the gas phase hold-up, for various gas rates and impeller geometry and speeds, and compared with values obtained from RTD measurements. A new correlation, involving Flow Number, Froude Number, system geometry and the physical properties, is proposed. This uses the authors data and those available in literature.  相似文献   
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105.
Foreword     
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106.
A method is described for experimentally determining the dose rate created in building bricks by incorporated natural radionuclides. It was established using the thermoluminescence dosimetry method that the measured dose rate depends on the detector thickness, the mass of the ceramic product investigated, and the irradiation geometry. The contributions to the measured dose of weakly penetrating α and β radiation and hard ψ radiation are separated, the ratio between them depending on the experimental conditions. Translated from Izmeritel'naya Tekhnika, No. 7, pp. 62–66, July, 1996.  相似文献   
107.
This article describes the phenomenon of morphological instability in solid-solid phase transformations during thin-film interdiffusion, specifically related to the initial stages of precipitation when phase growth occurs along the interface between thin films. The experimental observations that revealed this effect will be presented, and a working hypothesis will be discussed. Experimental observations suggest that the ledge mechanism of growth is present in this system but does not inhibit the formation of interfacial instabilities. It is proposed that morphological stability for solid-phase growth occurring during thin-film interdiffusion can be treated by the inclusion of a solute-source term into the two-dimensional perturbation approach generally used to study unstable growth morphologies. Experimental observations that provide qualitative and semiquantitative support for the solute-source model are also presented.  相似文献   
108.
This investigation retrospectively examined changes in marital satisfaction following stroke. The relationship between such changes and other pertinent factors were also examined, including severity of aphasia, knowledge of aphasia, number of months after stroke, and length of the marriage. The subjects were 40 spouses of patients with aphasia grouped according to severity of the aphasia (mild, moderate, severe). Spouses completed two different measures of marital satisfaction--the Marital Satisfaction Scale (MSS) and the Marital Comparison Level Index (MCLI). These measures were completed in both a prestroke (retrospective reporting) and a poststroke format to allow for change to be assessed. In addition, a Knowledge of Aphasia questionnaire was completed by the normal spouses to evaluate their understanding of the disorder of aphasia. There was a significant difference between prestroke and poststroke scores on both the MSS and the MCLI, indicating a lower level of satisfaction following the stroke. The amount of change between prestroke and poststroke MSS and MCLI scores was not related to either number of months poststroke or number of years married. Although there was no relationship between changes in prestroke and poststroke scores on the MCLI and Knowledge of Aphasia scores, there was a significant correlation between changes in these scores on the MSS and Knowledge of Aphasia scores. Hence, the more knowledge spouses had regarding aphasia, the less the negative impact the stroke had on marital satisfaction, as measured by the MSS. Results are discussed in terms of the interdisciplinary treatment needs of aphasic patients and the implications for future investigations.  相似文献   
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110.
The paper proposes a structure for quality-of-service (QoS)-centered service level agreements (SLA), and a framework for their real-time management in multiservice packet networks. The SLA is structured to be fair to both parties, the service provider and their customer. The SLA considered here are for QoS assured delivery of aggregate bandwidth from ingress to egress nodes; however, the control and signaling is for the more granular flows or calls. A SLA monitoring scheme is presented in which revenue is generated by the admission of flows into the network, and penalty incurred when flows are lost in periods when the service provider is not SLA compliant. In the SLA management scheme proposed, the results of a prior off-line design are used, in conjunction with measurements taken locally at ingress nodes, to classify the loading status of routes. The routing and resource management are based on virtual partitioning and its supporting mechanism of bandwidth protection. The effectiveness of SLA management is measured by the robustness in performance in the presence of substantial diversity in actual traffic conditions. A simulation testbed called D'ARTAGNAN has been built from which we report numerical results for a case study. The results show that the SLA management scheme is robust, fair and efficient over a broad range of traffic conditions  相似文献   
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