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71.
The authors report the results of a six months survey about the low weight of birth (L.W.B.) in the district of Guédiawaye, suburb of Dakar. The purpose is to determine the rate of L.W.B. in two main maternity hospitals of that locality and the associated risk factors. It is a survey with a control group. This survey results in a 10.7% rate, according to the data of another retrospective survey in the same maternity hospitals in 1992 (10.03%). The risk factors are mainly: celibacy, primiparity, an associated pathology with the pregnancy, the physical strain of mothers correlated to the income and to the previous L.W.B.  相似文献   
72.
In this long-term study, we wanted to explore the effect of dietary supplementation of seal oil (SO) as compared cod-liver oil (CLO) on subjects with moderate hypercholesterolemia. The test parameters included fatty acid composition in serum, blood lipids, platelet aggregation, and the activity of blood monocytes. After a run-in period of 6 mon, 120 clinically healthy hypercholesterolemic (7.0–9.5 mmol/L; 270–366 mg/dL) subjects were randomly selected to consume either 15 mL of SO or CLO daily for 14 mon followed by a 4-mon wash-out period. A third group was not given any dietary supplement (control). Consumption of marine oils (SO and CLO) changed the fatty acid composition of serum significantly. Maximal levels were achieved after 10 mon. No further changes were seen after 14 mon. A wash-out period of 4 mon hardly altered the level of n−3 fatty acids in serum. Addition of SO gave 30% higher level of eicosapentaenoic acid, as compared to CLO. Subjects taking SO or CLO had lower whole-blood platelet aggregation than the control group. Neither SO nor CLO had any effects on the levels of serum total cholesterol, high-density lipoprotein cholesterol, postprandial triacylglycerol, apolipoproteins A1 and B100, lipoprotein (a), monocyte function expressed as monocyte-derived tissue factor expression, and tumor necrosis factor.  相似文献   
73.
The origin of the extraordinary catalytic activity of gold nanoparticles is discussed on the basis of density-functional calculations, adsorption studies on single crystal surfaces, and activity measurements on well characterized supported gold particles. A number of factors are identified contributing to the activity, and it is suggested that it is useful to consider low-coordinated Au atoms as the active sites, for example, CO oxidation and that the effect of the support can be viewed as structural and electronic promotion. We identify the adsorption energy of oxygen and the Au-support interface energy as important parameters determining the catalytic activity.  相似文献   
74.
CaPiTo allows the modelling of service-oriented applications using process algebras at three levels of abstraction. The abstract level focuses on the key functionality of the services; the plug-in level shows how to obtain security using standardised protocol stacks; finally, the concrete level allows to consider how security is obtained using asymmetric and symmetric cryptographic primitives. The CaPiTo approach therefore caters for a variety of developers that need to cooperate on designing and implementing service-oriented applications. We show how to formally analyse CaPiTo specifications for ensuring the absence of security flaws. The method used is based on static analysis of the corresponding LySa specifications. We illustrate the development on two industrial case studies; one taken from the banking sector and the other a single sign-on protocol.  相似文献   
75.
A study was performed to explore the effects of supplemental intake of various marine oils known to be part of the Eskimo diet. Healthy men and women (134) were randomly selected to consume 15 mL/d of oil from blubber of seal, cod liver, seal/cod liver, blubber of Minke whale, or no oil for ten weeks. Total cholesterol was unchanged in the oil groups, whereas high density lipoprotein cholesterol increased 7% in the seal/cod liver oil (CLO) group (P<0.05) and 11% in the whale oil group (P<0.005). Triacylglycerol was significantly reduced in the CLO group only. The concentration of prothrombin fragment 1+2 was reduced 25% (P<0.05) after whale oil supplementation. No change in fibrinogen or factor VIIc was detected. Tumor necrosis factor generation in lipopolysaccharide (LPS)-stimulated blood was 30% reduced after whale oil (P<0.05), but was unaffected by intake of seal or CLO. The LPS-induced tissue factor activity in monocytes was reduced to a significant degree only in the seal/CLO group (34%) and whale oil group (35%) (P<0.05). The most dramatic change in thromboxane B2 in LPS-stimulated blood was seen after whale oil intake with 44% reduction (P<0.01). Supplementation of a regular diet with a combination of seal oil and CLO and especially with whale oil seems to have beneficial effects on several products thought to be associated with cardiovascular and thrombotic diseases.  相似文献   
76.
Cyber-physical systems integrate information and communication technology with the physical elements of a system, mainly for monitoring and controlling purposes. The conversion of traditional power grid into a smart grid, a fundamental example of a cyber-physical system, raises a number of issues that require novel methods and applications. One of the important issues in this context is the verification of certain quantitative properties of the system. In this paper, we consider a specific Chinese smart grid implementation as a case study and address the verification problem for performance and energy consumption. We employ stochastic model checking approach and present our modelling and analysis study using PRISM model checker.  相似文献   
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Low‐field 1H nuclear magnetic resonance (NMR) tranverse relaxations were measured on intact and minced muscle from raw and smoked salmon differing in size (small or large) and storage days after smoking (1, 11 and 20 days). Water distribution in the samples was calculated from the NMR signals by the use of multi‐way data analysis. For intact and minced salmon samples, three water ‘pools’ with T2 values of 38, 50 and 182 ms and of 33, 50 and 183 ms, respectively, were identified. For both intact and minced samples, the size of water pool I and II were affected by storage time after smoking, whereas the size of pool III was affected by the size of the fish. Intact fillet samples taken near the skin and near the middle of the fillet differed with respect to shape of the NMR relaxation signal reflecting a non‐uniform distribution of the size of the three water pools in intact fillet. Copyright © 2006 Society of Chemical Industry  相似文献   
80.
Sevan Marine and Siemens have developed a floating power plant – entitled Sevan GTW (gas-to-wire) – based on Sevan’s cylindrical platform and Siemens’ SCC-800 combined cycle, and SINTEF has adapted a post-combustion CO2 capture process for on board integration including compression and preconditioning of the CO2. Main emphasis has been placed on developing an optimised conceptual design within the structural constraints, and assessing how efficient the capture unit may be operated in consideration of the dynamic behaviour induced by the sea on the absorber and desorber columns via the floating carrier. The rational behind this technology selection is the urgency in making appropriate steps for a quick start for remote power generation at sea with the inclusion of CCS to serve offshore oil and gas operations. This calls for modular power blocks made up by high efficient combined power cycles with post-combustion exhaust gas cleaning. From this point of view a system with four absorption columns and one desorber unit has been determined based on structured packing material. The capture process has been integrated with the power cycle in due consideration of the sea forces. It is shown that a permanent tilt becomes more important than periodic movements provided the harmonic periods are kept within a certain level (<20 s). Operational conditions and constraints vis-à-vis movements and trimming of the floater have been addressed and discussed with reference to available literature. This also includes the liquid hold-up and gas–liquid interfacial area in the absorption columns linked with tilting. Optimisation reveals that a reboiler duty of 3.77 GJ/ton CO2 would result in the lowest capture cost. With a energy penalty of 9%-points the Sevan GTW concept presents itself as a realistic concept deemed to be within reach today.  相似文献   
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