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Quantum chemistry is based on the solution of the Schrödinger equation for a molecule. From starting data on the positions and nature of constituent atoms information is provided about the energy of the molecule and its electronic properties. The former can indicate what shapes drugs can adopt in binding to pharmacological receptors whilst electronic details, when compared using computer graphics, may highlight the factors responsible for biological activity. These techniques are beginning to show real successes in the design of drug molecules. 相似文献
978.
G. A. Alabi 《Information processing & management》1985,21(6):525-533
This paper presents the results of a comparative cost study of the manual circulation system and experimental automated system in a university library in Nigeria. Two sets of data were collected: one on the existing manual circulation system and the other on the experimental automated system on an Apple II microcomputer. Eight different circulation activities were identified for evaluation for which the direct labor cost of circulating a book on each system was calculated. The experimental automated system was found to be less labor intensive than the manual system, although overall unit cost of book circulation on the automated system was higher than on the manual system ($0.59 and $0.49, respectively). Factors attributed to the higher unit cost on the automated system were the cost of equipment and the low circulation figure. However, the automated system was found to be more effective in providing up-to-date and accurate data required for the monitoring of the library stock. 相似文献
979.
Recently, there has been a heavy debate in the US about the government’s use of data mining in its fight against terrorism.
Privacy concerns in fact led the Congress to terminate the funding of TIA, a program for advanced information technology to
be used in the combat of terrorism. The arguments put forward in this debate, more specifically those found in the main report
and minority report by the TAPAC established by the Secretary of Defense to examine the TIA issue, will be analysed to trace
the deeper roots of this controversy. This analysis will in turn be used as a test case to examine the adequacy of the usual
theoretical frameworks for these kinds of issues, in particular the notion of privacy. Whereas the dominant theoretical framing
of the notion of privacy turns around access to information, most of the core arguments in the debate do not fit in this kind of framework. The basic disagreements in
the controversy are not about mere access, they involve both access and use. Furthermore, whereas the issue of access by itself refers to a more or less static situation, the real disagreements much
more concern the organisational dynamics of the use of information, the mechanisms in the organisation that control these
dynamics, and the awareness present within the organisation of the ‘social risks’ these dynamics represent. The bottom line
question is whether the assessment of these gives sufficient reason for trust. 相似文献
980.
G. Kusumanjali Chinnapu G. Reddy A. S. Kanagasabapathy Pragna Rao 《Indian journal of clinical biochemistry : IJCB》2005,20(2):146-149
Accurate monitoring of blood cyclosporin C2 levels is vital to prevent over immunosuppression and acute renal toxicity in
patients who receive organ transplant. The matrix used to dilute patients’ C2 samples prior to the assay affected the final
measured values. Hence there was a need to develop a method of dilution that would accurately estimate C2 levels when cyclosporin
levels were beyond the calibration range of the method employed. Whole blood, cyclosporin free hemolysate and cell and protein
free supernatant obtained after pretreatment of normal blood were used to dilute patients’ C2 samples. C2 was measured in
188 patients using the supernatant method of dilution. C2 was correlated with Co and dose of cyclosporin received by the patient.
The use of cell and protein free supernatant obtained after pretreatment of normal blood as a C2 diluent detected higher levels
of C2 in the sample. Measured C2 correlated significantly with Co and the cyclosporin dose received by the patient. The uniformly
aqueous cell and protein free supernatant ensures uniform dilution of the patients’ C2 sample and measures higher cyclosporin
levels. 相似文献