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1.
Microsystem Technologies - This study presents the results on the feasibility of a resonant planar chemical capacitive sensor in the microwave frequency range suitable for gas detection and...  相似文献   
2.
In Norway, 65 % of the agricultural land is under grassland for feeding ruminants. The objective of the present study was to quantify N2O emissions from grassland on a fertile sandy loam in Western Norway, and to estimate the response of seasonal N2O emissions to added inorganic N, cattle slurry (CS) N and clover N. Ammonium nitrate (AN) and CS were applied manually at annual rates of 0, 100, 150, 200 and 250 kg AN-N ha?1, 80 kg CS-N ha?1 or as a combination of 200 kg AN-N ha?1 and 80 kg CS-N ha?1. Background N2O emissions were five times higher in summer season 2009 than in 2010, but the relative amount of N2O derived from AN was constant in both periods, amounting to 0.11 % of applied N. CS had no measurable impact on N2O emissions in 2009, but 0.15 % of CS-N was emitted as N2O during summer 2010. In the warm year of 2009, which included a drought period, 1–24 % of the N2O emissions were attributed to the effect of clover depending on fertilization. Clover had no effect on N2O fluxes in the cool and moist year 2010. Our results suggest that N2O emissions in fertile Norwegian grasslands are to a great extent controlled by inter-annual variations in background emissions and variable contribution of biologically fixed N and CS-N.  相似文献   
3.
This paper presents a driver simulator, which takes into account the information about the user’s state of mind (level of attention, fatigue state, stress state). The user’s state of mind analysis is based on video data and biological signals. Facial movements such as eyes blinking, yawning, head rotations, etc., are detected on video data: they are used in order to evaluate the fatigue and the attention level of the driver. The user’s electrocardiogram and galvanic skin response are recorded and analyzed in order to evaluate the stress level of the driver. A driver simulator software is modified so that the system is able to appropriately react to these critical situations of fatigue and stress: some audio and visual messages are sent to the driver, wheel vibrations are generated and the driver is supposed to react to the alert messages. A multi-threaded system is proposed to support multi-messages sent by the different modalities. Strategies for data fusion and fission are also provided. Some of these components are integrated within the first prototype of OpenInterface: the multimodal similar platform.  相似文献   
4.
The accurate solubility of salbutamol sulfate, budesonide, and formoterol fumarate dihydrate in hydrofluoroalkane propellant 134a at 25°C for 24 h, are reported. The authors describe a novel reusable in-line pressurized solubility apparatus containing an integral filter holder and a continuous decrimpable valve for the determination of drug/excipients solubility in pressurized metered dose inhalers. The solubility was determined by high-performance liquid chromatography. Solubility of salbutamol sulfate was determined as being below the detection limits while budesonide and formoterol fumarate dihydrate solubility were 23.136 ± 2.951 μg.g-1 and 0.776 ± 1.023 μg.g-1, respectively (n = 3). This novel solubility apparatus offers an improved ease of use and potential higher analytical throughput.  相似文献   
5.
Whether neurosteroids regulate the synthesis of long chain polyunsaturated fatty acids in brain cells is unknown. We examined the influence of 17-β-estradiol (E2) on the capacity of SH-SY5Y cells supplemented with α-linolenic acid (ALA), to produce eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA). Cells were incubated for 24 or 72 h with ALA added alone or in combination with E2 (ALA + E2). Fatty acids were analyzed by gas chromatography of ethanolamine glycerophospholipids (EtnGpl) and phosphatidylcholine (PtdCho). Incubation for 24 h with ALA alone increased EPA and DPA in EtnGpl, by 330 and 430% compared to controls (P < 0.001) and DHA by only 10% (P < 0.05). Although DHA increased by 30% (P < 0.001) in ALA + E2-treated cells, the difference between the ALA and ALA + E2 treatments were not significant after 24 h (Anova-1, Fisher’s test). After 72 h, EPA, DPA and DHA further increased in EtnGpl and PtdCho of cells supplemented with ALA or ALA + E2. Incubation for 72 h with ALA + E2 specifically increased EPA (+34% in EtnGpl, P < 0.001) and DPA (+15%, P < 0.001) compared to ALA alone. Thus, SH-SY5Y cells produced membrane EPA, DPA and DHA from supplemental ALA. The formation of DHA was limited, even in the presence of E2. E2 significantly favored EPA and DPA production in cells grown for 72 h. Enhanced synthesis of ALA-elongation products in neuroblastoma cells treated with E2 supports the hypothesis that neurosteroids could modulate the metabolism of PUFA.  相似文献   
6.
A strategic analysis of the electricity market in Western Australia yields a market potential for renewable energy in Western Australia. However, from a purely financial viewpoint the installation of grid-connected pv-systems still is not economically viable. In this paper a balanced scorecard (BSC) is developed to capture and visualize other than financial benefits. Therefore, the BSC can be used as a marketing tool to communicate the benefits of a privately owned GCPV system to potential customers.  相似文献   
7.
The World Health Organization/EURO Multicentre Project on Parasuicide is part of the action to implement target 12 of the WHO programme, "Health for All by the Year 2000', for the European region. Sixteen centres in 13 European countries are participating in the monitoring aspect of the project, in which trends in the epidemiology of suicide attempts are assessed. The highest average male age-standardized rate of suicide attempts was found for Helsinki, Finland (314/100,000), and the lowest rate (45/100,000) was for Guipuzcoa, Spain, representing a sevenfold difference. The highest average female age-standardized rate was found for Cergy-Pontoise, France (462/100,000), and the lowest (69/100,000) again for Guipuzcoa, Spain. With only one exception (Helsinki), the person-based suicide attempt rates were higher among women than among men. In the majority of centres, the highest person-based rates were found in the younger age groups. The rates among people aged 55 years or over were generally the lowest. For the majority of the centres, the rates for individuals aged 15 years or over decreased between 1989 and 1992. The methods used were primarily "soft' (poisoning) or cutting. More than 50% of the suicide attempters made more than one attempt, and nearly 20% of the second attempts were made within 12 months after the first attempt. Compared with the general population, suicide attempters more often belong to the social categories associated with social destabilization and poverty.  相似文献   
8.
CFB锅炉内成灰特性的实验研究方法   总被引:4,自引:1,他引:4  
The material balance in CFB furnace is important for the performance of the boiler.The bed inventory consists of coal ash and desulfurizing agent.In order to design properly the boiler and auxiliary,the engineers need to know the ash formation characteristics. Generally, the most reliable method to get ash formation data of a coal is to burn it in the real industrial CFB boiler. Due to the high cost and difficulties in sampling in such a test,people have to present other simple method on ash formation.The present investigation is proposing a simple laboratory test procedure to study ash formation by static combustion and sieving.Validation of the method is given.  相似文献   
9.
Focused ion beam (FIB) milling is one of the few specimen preparation techniques that can be used to prepare parallel-sided specimens with nm-scale site specificity for examination using off-axis electron holography in the transmission electron microscope (TEM). However, FIB milling results in the implantation of Ga, the formation of amorphous surface layers and the introduction of defects deep into the specimens. Here we show that these effects can be reduced by lowering the operating voltage of the FIB and by annealing the specimens at low temperature. We also show that the electrically inactive thickness is dependent on both the operating voltage and type of ion used during FIB milling.  相似文献   
10.
The fatty acid composition of serum total lipids, of phospholipids of various organs (liver, heart, kidney), and of nervous structures (brain, retina, sciatic nerve, myelin, synaptosomes) have been compared in lean (Fa/−) and genetically obese (fa/fa) Zucker female rats. Both received a standard commercial diet including 37% of 18∶2n−6 and 5% of n−3 polyunsaturated fatty acids (PUFA), 1.7% of which were in the form of 20∶5n−3 and 22∶6n−3. In comparison with lean rats, the results for the obese rats pointed out (i) no difference in the fatty acid composition of nervous structures: (ii) a decrease of 18∶2n−6 (from −8% to −35%) and of 20∶4n−6 (from −9% to −49%) in serum, liver and in kidney; this was compensated for by an increase in 20∶3n−6 (from +30% to +320%) and in total n−3 PUFA (from +68% to +76%); (iii) a decrease of 20∶4n−6 (−18%) and of 22∶6n−3 (−24%) in heart compensated for by an increase in 18∶2n−6 (+39%) and in 20∶3n−6 (+233%); and (iv) constant levels of total PUFA (n−6 and n−3) in the various fractions studied, except in serum where this level decreased (−23%). Finally, except for the nervous structures, tissue phospholipids of obese rats included a lower proportion of 20∶4n−6 and a higher proportion of 20∶3n−6. This resulted in a significant reduction in the 20∶4n−6/20∶3n−6 ratio; by contrast, the 20∶3n−6/18∶2n−6 ratio increased. The results suggest that in Zucker rats, the obese character (fa/fa) affects the desaturation-elongation process of 18∶2n−6 to 20∶4n−6 by specifically decreasing Δ5-desaturase activity.  相似文献   
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