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81.
E Malik W B?hm F Stoz CD Nitsch WG Rossmanith 《Canadian Metallurgical Quarterly》1998,12(11):1326-1333
BACKGROUND: Laparoscopy can be used with minimal operative morbidity to evaluate adnexal masses. We report our experience with the endoscopic approach to the diagnosis and treatment of ovarian tumors. In particular, we describe 11 patients who incidentally underwent laparoscopy and in whom the ovarian masses were found to be malignant. METHODS: Between September 1994 and September 1996, 292 patients with 316 ovarian tumors were treated laparoscopically in the Department of Obstetrics-Gynaecology, University of Ulm. We assessed vaginal ultrasonography, clinical assessment, the tumor marker CA 12-5, and the intraoperative low-power magnification for their value in predicting the final diagnosis in all laparoscopically treated ovarian tumors. RESULTS: From a total of 292 patients with ovarian tumors, 11 were diagnosed, intraoperatively or after final histologic examination, as having a malignant or borderline ovarian tumor. All applied pre- and intraoperative diagnostic procedures were by themselves too unreliable to exclude early stages of ovarian carcinoma exactly. CONCLUSIONS: On the basis of the present findings, we are tempted to conclude that laparoscopic surgery is justified in the management of ovarian tumors. Even with an accurate preoperative selection of suitable patients for laparoscopic surgery, the presence of an undetected ovarian carcinoma cannot be entirely excluded. 相似文献
82.
GM Malik 《Canadian Metallurgical Quarterly》1998,59(3):397-398
In a retrospective case-control study of 58 cases of human brucellosis, adjusted mean serum calcium levels were found to be significantly higher in patients with brucellosis compared with controls: mean (95% confidence interval) = 2.39 (2.35-2.42) mmol/L versus 2.30 (2.26-2.34) mmol/L (P = 0.0012). The possible mechanisms underlying the cause of hypercalcemia in human brucellosis are discussed. 相似文献
83.
84.
We study the problem of how to minimize the cost of maintaining consistency among at least N copies of an object in an enviroment where the mix of read and write operations can vary. Quorum consensus requires that
read and write operations must assemble appropriate quorums before an operation can succeed. The cost of an operation is proportional
to the size of a quorum, and the objective is obviously to minimize the cost while still maintaining consistency. It is known
that the quorum size can be reduced by organizing a number of copies into logical structures such as grids and hierarchies.
In this paper, we show (a) how methods based on grids and hierarchies can be treated in a common framework, and (b) how these
hierarchies can be optimized so as to minimize the cost of consensus. Of course, the optimal solution depends upon the mix
of read and write operations that is present. Consequently, given N copies of an object and a ratio of write operations F, our algorithms determine the optimal values for the number of levels
in the hierarchy and the read/write quorum sizes at each level. The algorithms, which run in O(N
1.63) and O(N
2) time, were tested, and the results are reported and discussed.
Received September 1, 1992/February 16, 1995 相似文献
85.
Dye removal from wastewater using activated carbon developed from sawdust: adsorption equilibrium and kinetics 总被引:13,自引:0,他引:13
Malik PK 《Journal of hazardous materials》2004,113(1-3):81-88
Mahogany sawdust was used to develop an effective carbon adsorbent. This adsorbent was employed for the removal of direct dyes from spent textile dyeing wastewater. The experimental data were analysed by the Langmuir and Freundlich models of adsorption. Equilibrium data fitted well with the Langmuir model. The rates of adsorption were found to conform to the pseudo-second-order kinetics with good correlation. The equilibrium adsorption capacity of the sawdust carbon was determined with the Langmuir equation as well as the pseudo-second-order rate equation and found to be >300 mg dye per gram of the adsorbent. The most ideal pH for adsorption of direct dyes onto sawdust carbon was found to be 3 and below. The results indicate that the Mahogany sawdust carbon could be employed as a low cost alternative to commercial activated carbon in the removal of dyes from wastewater. 相似文献
86.
Anthony D. Caunt John A. Licchelli Ian W. Parsons Robert N. Haward Malik R.Y. Al-Hillo 《Polymer》1983,24(1):121-125
Reduction of TiCl4 with organomagnesiums either in the presence of preformed MgCl2, or concurrently with the formation of MgCl2 from chlorocarbons, yields materials which are active catalysts for the polymerization of propene and ethene. Transformation of these materials to a violet allotrope by heating with TiCl4 gives materials much more active for propene polymerization, albeit stereoregulation is still not good. interestingly, these transformed materials show little advantage for ethene polymerization except at high temperatures. Use of a Lewis base does not give high stereoregulation with propene; although some advantage is gained activity is greatly diminished by this. 相似文献
87.
Costas Busch Malik Magdon-Ismail Marios Mavronicolas 《Journal of Parallel and Distributed Computing》2007
In bufferless networks the packets cannot be buffered while they are in transit; thus, once injected, the packets have to move constantly. Bufferless networks are interesting because they model optical networks. The objective of this work is to demonstrate that efficient bufferless packet switching is achievable in particular, interesting network topologies. 相似文献
88.
M. Mobin A. U. Malik S. Al-Fozan F. Al-Muaili 《Journal of Failure Analysis and Prevention》2007,7(1):18-22
This paper describes the investigation of a corrosion failure of bottom plates on an aboveground tank used for the storage
of potable water. The tank was internally inspected for the first time after six years of service. Paint blisters and rust
spots were observed on the bottom plates and first to third course shell plates. Sand blasting and repainting of the bottom
plates and first course shell plates was to be used as a remedial measure. However, during the sand blasting, holes and deep
pitting were observed on the bottom plates. On-site visual inspection, magnetic flux leakage (MFL) inspection, ultrasonic
testing (UT), and evaluation of the external cathodic protection (CP) system were used in the failure analysis. The corrosion
products were analyzed using energy-dispersive X-ray analysis (EDAX). The failure is attributed to the ingress of water and
its impoundment under the tank bottom along the periphery inside the ring wall and failure of water side epoxy coating. Various
measures to prevent such failures in the future are recommended. 相似文献
89.
Fixed points provide a reliable way to realize and verify temperature scales. High-temperature fixed points are being developed
based upon alloys, since single-phase materials are impractical to use above the copper freezing point. In particular, eutectic
alloys have been shown to be sufficiently reproducible to warrant consideration as a way to significantly improve high-temperature
metrology. However, eutectic alloys have certain characteristics requiring that they are used differently from the current
ITS-90 fixed points. As their freezing temperature depends on the freezing rate, the melting temperature is preferred, though
it has been shown that for some alloys, notably iron–carbon and cobalt–carbon, the apparent melting temperature can depend
on the rate of the preceding freeze. This behavior will need to be explained and quantified if such fixed points are to be
acceptable. The effect of varying the freezing rate on subsequent melting has been investigated for cobalt–carbon eutectic
fixed points. The apparent melting temperature varies by up to 50 mK. Measurements were made of two different fixed-point
blackbodies with very similar results. Optical microscopy of samples produced at different freeze rates shows a change in
scale of the microstructure. Electron back-scatter diffraction (EBSD) shows evidence of high levels of residual strain in
rapidly frozen samples. The effect of annealing on the melting behavior and microstructure has also been investigated. It
is suggested that disordered phase boundaries and residual strain lead to changes in the melting behavior as nonequilibrium
conditions may lead to a significant level of pre-melting. Whether this actually changes the liquidus temperature, or whether
the melting temperature variation is due to the way the melting point is defined, is also discussed. The variation requires
consideration if the highest accuracy is to be achieved, and will be a contributory factor to any uncertainty budget. 相似文献
90.
M. Khurshid Z. Barsoum I. Barsoum T. Däuwel 《Fatigue & Fracture of Engineering Materials & Structures》2016,39(10):1281-1298
In this study, the fatigue strength of inclined butt welds subjected to a proportional multiaxial stress state generated by uniaxial loading is studied in nominal and local stress concepts. The local methodologies studied included principal stress hypothesis, von Mises stress hypothesis and modified Wöhler curve method. Nominal methodologies included modified Gough–Pollard interaction equation, the design equation in Eurocode3 and the interaction equation in DNV standard. Results are evaluated along with data published in relevant literature. It is observed that both local and nominal stress assessment methods are able to estimate multiaxial fatigue strength. No obvious difference in fatigue strength is observed in the nominal stress concept, but the notch stress concept is able to capture a decrease in fatigue strength in shear‐dominated joints. It is concluded that modified Wöhler curve method is a suitable tool for the evaluation of fatigue strength in joints dominated by both normal and shear stresses. 相似文献