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A study of the efficacy of cefuroxime axetil was conducted for the treatment of acute sinusitis in childhood. Thirty-nine patients aged 5-14 years were given cefuroxime axetil 20 mg/kg/day divided into two doses for seven days. The diagnosis of acute sinusitis was based on history, physical examination, and radiological findings. The results of throat cultures before treatment were 17 patients with group A beta-haemolytic streptococci, seven patients with pneumococci, and two patients with Staphylococcus aureus; in the remainder of the patients only normal throat flora were isolated. In 36 patients (92%) a satisfactory improvement was reported at the end of the treatment. It was found that cefuroxime axetil was efficaceous for the treatment of sinusitis in childhood. 相似文献
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Temperature control systems based on solar and wind energy differ in two important ways from existing fossil fuel systems. One is that solar systems, at least active solar systems, all have some kind of energy storage, the other is that the source of energy in a solar and wind energy system is variable and uncontrollable. Because of these added complications and the high capital investment required for solar and wind energy systems, considerably more sophisticated techniques are required for the design of those systems. In this study, a new technique is applied to the optimal control problem of solar heating systems. 相似文献
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In this letter, we investigate the shadowing effect on the performance of space-time codes, using the Rician-Nakagami channel model which has been recently introduced. Specifically, we derive an exact expression for the pairwise error probability (PEP) of space-time trellis codes over the Rician-Nakagami channel, which is in the form of a simple single finite-range integral. We also present numerical results how the PEP expressions for the Rician-Nakagami channel can be related to those for the classical Rician-lognormal channel based on the parameter transformation between these two models. 相似文献
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Cascaded Rayleigh distribution is used to model multipath fading in mobile-to-mobile communication scenarios and provides a better fit to experimental data in such scenarios compared to the conventional Rayleigh channel model. In this letter, we derive an exact expression for the pairwise error probability (PEP) of space-time trellis codes over the cascaded Rayleigh fading channel, which is in the form of a simple single finite-range integral. Through the derived PEP expression, we present the maximum diversity order achievable over such channels and demonstrate the performance degradation in comparison to conventional Rayleigh channels. Monte-Carlo simulations are further demonstrated to confirm the analytical results. 相似文献
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Serum IgG, IgG1, G2, G3, G4, IgM, C3c and C4 concentrations were measured in 24 term neonates with sepsis and 17 healthy normal neonates of similar age, sex and weight (control group). The serum IgG, IgG1, G2, G3, G4, IgM, C3c, and C4 levels were similar in the patients with sepsis and the control group (p > 0.05). In the neonates with sepsis, serum IgG, G1, G2, IgM and C4 levels were not significantly different between the 1st and 10th days, while there were significant differences for IgG3, G4 and C3c (p < 0.05). We conclude that the serum levels of IgG, IgG1, G2, G3, G4, IgM, C3c and C4 concentrations are of no value for the early diagnosis of neonatal sepsis. 相似文献
28.
Kallahalla M. Uysal M. Swaminathan R. Lowell D.E. Wray M. Christian T. Edwards N. Dalton C.I. Gittler F. 《Computer》2004,37(11):38-46
Utility computing aims to aggregate server, network, and storage systems into a single, centrally managed pool of resources. SoftUDC, a virtual machine monitor, lets applications and administrative domains share physical resources while maintaining full functional isolation. 相似文献
29.
In mergers and acquisitions (M&A), a primary objective of acquirer is to integrate IT resources of the target with its own. IT M&A integration is assumed to create synergies, which in turn increase shareholder wealth by making the value of the merged firm greater than the sum of the standalone values of the two firms. In this study, we challenge this assumption and argue that IT M&A integration does not always lead to greater value creation. Prior research on IT M&A integrations indicates that IT resources are often not scale-free in M&A: that is, they do not transfer easily and costlessly from an acquirer to its target or vice versa. In fact, IT M&A integration can destroy value rather than create it when IT resources are not scale-free. We theorize about the contingencies under which IT M&A integration can create value for shareholders of acquirers. We test our hypotheses in a sample of 549 M&A transactions between 1998 and 2007. We find that, on average, capital markets react negatively with M&A announcements of acquirers whose IT capabilities are superior relative to those of the targets. The superiority of the acquirer’s IT capabilities signals that the acquirer is likely to rip and replace IT resources of the target. This IT M&A integration approach increases risks of disruption to target’s operations and revenue growth. Capital markets take such risks into account and reduce the stock price of the acquirer. One contingency that reduces the negative reactions of capital markets is industry relatedness of target. In a same-industry acquisition, an acquirer and its target have similar operating models, competitive dynamics, and regulatory context. Thus, ripping and replacing weaker IT resources of the target with superior IT resources of the acquirer creates expectations of more efficient operation, engenders positive stock price reactions, and increases shareholder wealth. Another contingency that reduces the negative reactions of capital markets is the acquirer’s track record in profitable growth. A profitably growing acquirer that has superior IT capabilities increases the confidence of capital markets that it can minimize potential disruption risks of IT integration, continue its profitable growth pattern with newly acquired target, engender positive stock price reactions, and create shareholder wealth. These findings indicate that IT M&A integration does not always lead to greater value creation in M&A. The study makes a contribution by identifying the contingencies under which IT M&A integration creates wealth for acquirer’s shareholders. 相似文献
30.
In this study, a new slip-line field model and its associated hodograph for orthogonal cutting with a rounded-edge worn cutting tool are developed using Dewhurst and Collins's matrix technique. The new model considers the existence of dead metal zone in front of the rounded-edge worn cutting tool. The ploughing force and friction force occurred due to flank wear land, chip up-curl radius, chip thickness, primary shear zone thickness and length of bottom side of the dead metal zone are obtained by solving the model depending on the experimental resultant force data. The effects of flank wear rate, cutting edge radius, uncut chip thickness, cutting speed and rake angle on these outputs are specified. 相似文献