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41.
We present the case of a young female who suffered a massive intracerebral bleed following the ingestion of a small quantity of amphetamine (speed). Physicians should be aware that amphetamine abuse can lead to cerebrovascular events in young adults. 相似文献
42.
HO Ammar M Ghorab SA el-Nahhas SM Omar MM Ghorab 《Canadian Metallurgical Quarterly》1995,50(12):805-808
This study is a retrospective review of admissions, discharge records and blood culture results of neonates admitted to the Neonatal Intensive Care Unit of Korle Bu Teaching Hospital in Accra, from the first of January 1991 to the 31st of December 1992. During this two year period there were 443 positive blood cultures. Ninety percent of the blood cultures were from babies born in Korle Bu Teaching Hospital, thus making the incidence of neonatal bacteraemia 22.2 per 1000 live births. The overall mortality rate was 37.2%. Gram negative bacteria accounted for 70.9% and Gram positive bacteria for 29.1% of all neonatal bacteraemia. The most common isolates were Enterobacter species 29.6%; Streptococcus faecalis 14.4%; Staphylococcus aureus 10.8%; Acinetobacter species 9.5%; Klebsiella species 9% and Escherichia coli 8.8%. It is concluded that the incidence of neonatal bacterial sepsis is high in our hospital and is associated with a very high mortality rate. There is thus an urgent need to institute appropriate preventive and therapeutic measures. 相似文献
43.
44.
Performance Assessment of a New Radiation Microsensor Based 4H-SiC trench MOSFET: A Simulation Study
Silicon - The MOSFET has been widely used as a detector for high-energy radiations in areas like nuclear energy and medical treatments. Generally, the shift in threshold voltage of the... 相似文献
45.
Mithat Gonen Madan L. Puri Frits H. Ruymgaart & Martien C. A. van Zuijlen 《时间序列分析杂志》2000,21(3):249-260
In this note we introduce a simple principle to derive a constructive expression for the density of the limiting distribution, under the null hypothesis, of unit root statistics for an AR(1)-process in a variety of situations. We consider the case of unknown mean and reconsider the well-known situation where the mean is zero. For long-range dependent errors we indicate how the principle might apply again. We also show that in principle the method also works for a near unit root case. Weak convergence and subsequent Karhunen-Loeve expansion of the weak limit of the partial sum process of the errors plays an important role, along with the evaluation of a certain normal type integral with complex mean and variance. For independent and long range dependent errors this weak limit is ordinary and fractional Brownian motion respectively.
AMS 1991 subject classification. Primary 62M10; secondary 62E20. 相似文献
AMS 1991 subject classification. Primary 62M10; secondary 62E20. 相似文献
46.
Dinesh Kumar Mishra Jasaswini Tripathy Madan Mohan Mishra Kunj Behari 《应用聚合物科学杂志》2008,110(6):3455-3463
The optimum conditions for grafting N‐vinyl‐2‐pyrrolidone onto dextran initiated by a peroxydiphosphate/thiourea redox system were determined through the variation of the concentrations of N‐vinyl‐2‐pyrrolidone, hydrogen ion, potassium peroxydiphosphate, thiourea, and dextran along with the time and temperature. The grafting ratio increased as the concentration of N‐vinyl‐2‐pyrrolidone increased and reached the maximum value at 24 × 10?2 mol/dm3. Similarly, when the concentration of hydrogen ion increased, the grafting parameters increased from 3 × 10?3 to 5 × 10?3 mol/dm3 and attained the maximum value at 5 × 10?3 mol/dm3. The grafting ratio, add‐on, and efficiency increased continuously with the concentration of peroxydiphosphate increasing from 0.8 × 10?2 to 2.4 × 10?2 mol/dm3. When the concentration of thiourea increased from 0.4 × 10?2 to 2.0 × 10?2 mol/dm3, the grafting ratio attained the maximum value at 1.2 × 10?2 mol/dm3. The grafting parameters decreased continuously as the concentration of dextran increased from 0.6 to 1.4 g/dm3. An attempt was made to study some physicochemical properties in terms of metal‐ion sorption, swelling, and flocculation. Dextran‐g‐N‐vinyl‐2‐pyrrolidone was characterized with infrared spectroscopy and thermogravimetric analysis. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
47.
Hybrid magnetic nanostructures with high coercivity have immense application potential in various fields. Nickel (Ni) electrodeposited inside Cobalt (Co) nanotubes (a new system named Ni @ Co nanorods) were fabricated using a two-step potentiostatic electrodeposition method. Ni @ Co nanorods were crystalline, and they have an average diameter of 150 nm and length of ~15 μm. The X-ray diffraction studies revealed the existence of two separate phases corresponding to Ni and Co. Ni @ Co nanorods exhibited a very high longitudinal coercivity. The general mobility-assisted growth mechanism proposed for the growth of one-dimensional nanostructures inside nano porous alumina during potentiostatic electrodeposition is found to be valid in this case too. 相似文献
48.
Groundwater management and development by integrated remote sensing and geographic information systems: prospects and constraints 总被引:12,自引:3,他引:12
Madan K. Jha Alivia Chowdhury V. M. Chowdary Stefan Peiffer 《Water Resources Management》2007,21(2):427-467
Groundwater is one of the most valuable natural resources, which supports human health, economic development and ecological
diversity. Overexploitation and unabated pollution of this vital resource is threatening our ecosystems and even the life
of future generations. With the advent of powerful personal computers and the advances in space technology, efficient techniques
for land and water management have evolved of which RS (remote sensing) and GIS (geographic information system) are of great
significance. These techniques have fundamentally changed our thoughts and ways to manage natural resources in general and
water resources in particular. The main intent of the present paper is to highlight RS and GIS technologies and to present
a comprehensive review on their applications to groundwater hydrology. A detailed survey of literature revealed six major
areas of RS and GIS applications in groundwater hydrology: (i) exploration and assessment of groundwater resources, (ii) selection
of artificial recharge sites, (iii) GIS-based subsurface flow and pollution modeling, (iv) groundwater-pollution hazard assessment
and protection planning, (v) estimation of natural recharge distribution, and (vi) hydrogeologic data analysis and process
monitoring. Although the use of these techniques in groundwater studies has rapidly increased since early nineties, the success
rate is very limited and most applications are still in their infancy. Based on this review, salient areas in need of further
research and development are discussed, together with the constraints for RS and GIS applications in developing nations. More
and more RS- and GIS-based groundwater studies are recommended to be carried out in conjunction with field investigations
to effectively exploit the expanding potential of RS and GIS technologies, which will perfect and standardize current applications
as well as evolve new approaches and applications. It is concluded that both the RS and GIS technologies have great potential
to revolutionize the monitoring and management of vital groundwater resources in the future, though some challenges are daunting
before hydrogeologists/hydrologists. 相似文献
49.
目的探讨在血管内弹簧圈栓塞颅内动脉瘤过程中出现弹簧圈移位、突出或脱出和解旋等危急事件的原因及支架应用的价值。方法回顾性分析12例弹簧圈栓塞颅内动脉瘤出现危急事件的病例,其中9例为宽颈动脉瘤;10例出现动脉瘤破裂出血;2例动脉瘤最大径为5~12mm,7例为3~5mm,3例<3mm;造影和临床随访超过18个月。结果危急事件为弹簧圈移位3例,突出或脱出7例,解旋2例。处理方法为8例植入了支架,无一例出现缺血事件;未植入支架的4例中解旋1例,成功回收,突出或脱出3例。术后2例出现缺血事件。随访造影未见支架内狭窄和再出血事件。结论利用支架处理这些危急事件可行、有效;弹簧圈的危急事件与弹簧圈与动脉瘤大小不匹配、后置弹簧圈填塞、过度填塞和微导管操作等因素有关。 相似文献
50.
The Konan groundwater basin of Kochi Prefecture, Japan, is experiencing freshwater shortages for the past few years, particularly during the winter season. The present study aimed at analyzing the problem and exploring increased groundwater withdrawals to meet burgeoning freshwater demands in various sectors. The trend analysis of waterconsumption indicates that the groundwater demandwould increase by 43 and 52% by the years 2010 and2025, respectively, compared to 32 100 m3 d-1 at present.The streamflow of the Monobe River reduces to a minimumin winter and it shows a decreasing trend in recentyears. The geologic investigation results indicatethat unconfined (phreatic) aquifers comprisingalluvial sand and gravel and/or diluvial silty sandand gravel are dominant, and that the northwestern andwestern portions of the basin have greater potentialfor groundwater. Groundwater flows essentially fromnorth to south into the ocean. Groundwater levelfluctuations over the basin vary appreciably in spaceand time, indicating a wide variation of naturalrecharge. Field observations confirm the hypothesisthat stream-aquifer interaction also significantlycontributes to groundwater recharge, besides therainfall infiltration. Further, the pumping testsresults demonstrate that though the aquifers arelow-yielding, enhanced groundwater withdrawals couldbe possible. The aquifer hydraulic conductivity ischaracterized as high and ranges from 65 to 804 m d-1(mean = 229 m d-1), thereby suggesting great aquiferheterogeneity. Finally, it is concluded that thelong-term sustainability of the scarce groundwaterresource of the Konan basin is doubtful, and that acomprehensive analysis of the groundwater system isessential prior to formulating plans for the futuregroundwater development and management. 相似文献