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排序方式: 共有356条查询结果,搜索用时 15 毫秒
21.
Hannu Linkola 《Landscape Research》2015,40(8):939-954
AbstractIn 2010, the Finnish Ministry of the Environment launched a re-evaluation and revision of the 1993 inventory of Nationally Valuable Landscape Areas (NVLAs). While the inventory works for implementation of the National Land Use Guidelines, it also showcases the use of landscapes in Finnish national heritage policy. Based on critical readings of three influential Finnish administrative landscape policy reports, I claim that NVLAs, as tools of heritage policy, are based on the approaches and methodologies that have supported Finland’s development into a modern nation state by providing tools for intellectual governance of the national past and territory. Rather than meeting the diversity of landscape conceptions, as defined in the European Landscape Convention, the NVLAs run a risk of being in conflict with citizens and actors that do not share the administrative assumption of landscapes as public containers of national heritage. 相似文献
22.
Sami Myllymaa Emilia Kaivosoja Katja Myllymaa Tarvo Sillat Hannu Korhonen Reijo Lappalainen Yrj? T. Konttinen 《Journal of materials science. Materials in medicine》2010,21(1):329-341
It was hypothesized that human mesenchymal stromal cell (hMSC) can be guided by patterned and plain amorphous diamond (AD),
titanium (Ti), tantalum (Ta) and chromium (Cr) coatings, produced on silicon wafer using physical vapour deposition and photolithography.
At 7.5 h hMSCs density was 3.0–3.5× higher (P < 0.0003, except Ti) and cells were smaller (68 vs. 102 μm, P 0.000006–0.02) on patterns than on silicon background. HMSC-covered surface of the background silicon was lower on Ti than
AD patterns (P = 0.015), but at 5 days this had reversed (P = 0.006). At 7.5 h focal vinculin adhesions and actin cytoskeleton were outgoing from pattern edges so cells assumed geometric
square shapes. Patterns allowed induced osteogenesis, but less effectively than plain surfaces, except for AD, which could
be used to avoid osseointegration. All these biomaterial patterns exert direct early, intermediate and late guidance on hMSCs
and osteogenic differentiation, but indirect interactions exist with cells on silicon background. 相似文献
23.
Eylem Dizman Tomak Mark Hughes Umit C. Yildiz Hannu Viitanen 《Journal of Materials Science》2011,46(3):598-607
The aim of the study was to screen any possible synergistic effect available with combination of plant oils and boron compounds
to decrease boron leaching and improve thermal degradation of wood by means of dual treatment. In order to reduce the leachability
of boron compounds, sapwood of beech and Scots pine samples were treated with oils to create a hydrophobic layer on the wood
cells that may prevent water uptake. Increase (%) of boron retained in double-treated samples after leaching was approximately
20% compared to boron-treated samples without oil. The most promising results on boron leaching obtained in the case of using
waste and sunflower oil. Thermogravimetric residues were increased by the higher loading of boron compounds in double-treated
samples. Spectra of FTIR-Photoacoustic spectrometer showed some deformation of lignin and cellulose followed by degradation
of hemicelluloses of treated wood samples due to heat effect at 160 °C. 相似文献
24.
M Leirisalo-Repo P Helenius T Hannu A Lehtinen J Kreula M Taavitsainen S Koskimies 《Canadian Metallurgical Quarterly》1997,56(9):516-520
OBJECTIVES: Reactive joint complications triggered by salmonella gastroenteritis are increasingly reported, but the outcome and long term prognosis of the patients is incompletely known. This study looked at the prognosis of salmonella arthritis in patients hospitalised in 1970-1986. METHODS: Hospital records from two hospitals in southern Finland were screened for patients with the discharge diagnosis of salmonellosis or reactive, postinfectious arthritis or Reiter's disease. For the patients with confirmed diagnosis of reactive salmonella arthritis, data about the acute disease were collected from the hospital records. A follow up study was performed. RESULTS: There were 63 patients (28 women, 35 men, mean age 36.5 years) with salmonella arthritis. Urethritis occurred in 27%, eye inflammation in 13%, and low back pain in 44% of the patients. HLA-B27 was present in 88%. More men than women were HLA-B27 positive. HLA-B27 positive patients had higher erythrocyte sedimentation rate (mean 80.9 v 46.5 mm 1st h, p = 0.0180). Also, extra-articular features and radiological sacroiliitis were seen only in HLA-B27 positive patients. A follow up study was performed on 50 patients mean 11.0 (range 5-22 years) later. Twenty patients had recovered completely. Ten patients had mild joint symptoms, 11 patients had had a new acute transient arthritis, and five acute iritis. Eight patients had developed chronic spondyloarthropathy. Radiological sacroiliitis was seen in six of 44 patients, more frequently in male than in female patients (32% v 0%; p = 0.0289). Recurrent or chronic arthritis, iritis or radiological sacroiliitis developed only in HLA-B27 positive patients. CONCLUSION: Joint symptoms are common after reactive salmonella arthritis. HLA-B27 contributes to the severity of acute disease and to the late prognosis. 相似文献
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27.
Iiro Hietanen Jukka Lindgren Risto Orava Tuure Tuuva Martti Voutilainen
Richard Brenner
Mikael Andersson
Kari Leinonen Hannu Ronkainen 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1991,310(3):671-676Double-sided silicon strip detectors with integrated coupling capacitors and polysilicon resistors have been processed on a 100 mm wafer. A detector with an active area of 19 × 19 mm2 was connected to LSI readout electronics and tested. The strip pitch of the detector is 25 μm on the p-side and 50 μm on the n-side. The readout pitch is 50 μm on both sides. The number of readout strips is 774 and the total number of strips is 1161. On the p-side a signal-to-noise of 35 has been measured using a 90Sr β-source. The n-side has been studied using a laser. 相似文献
28.
Pertti Aaltonen Rauno Rintamaa Hannu Hnninen Ulla Ehrnstn Esko Arilahti 《Nuclear Engineering and Design》1993,144(1)
Samples of a low alloy steel piping material taken from the full scale corrosion fatigue test loop of the Heissdampfreaktor (HDR) plant have been tested at 240°C in high oxygen reactor water. The small-scale specimens (CT25) were exposed to a similar loading spectrum to that which has been used in the full-scale corrosion fatigue tests at the HDR-plant. During the autoclave tests cyclic crack growth rates were determined. Fracture surface investigations were performed not only for the laboratory test specimens but also for the fracture surface of a sample taken from the HDR test loop piping after the full scale test. In this paper the autoclave testing results and fracture surface observations are presented and compared to those obtained in the HDR piping tests. 相似文献
29.
Adam Strak Andreas Gothenberg Hannu Tenhunen 《Analog Integrated Circuits and Signal Processing》2004,41(2-3):223-236
This paper presents a theoretical overview and analysis of clock jitter in a switched capacitor (SC) Sigma-Delta (ΣΔ) Analog-to-Digital Converter (ADC). We start by defining three different types of jitter effects and proceed to analyze their impact, both mathematically and by simulations. The main jitter assumption throughout this analysis is that it is stochastic white Gaussian noise. Using this assumption, the ΣΔ performance is characterized in terms of Signal-to-Jitter-Noise-Ratio (SJNR) for each jitter effect. Non-uniform sampling effects have, to some extent, been characterized in litterature (S.R. Norsworthy, R. Schreier and G.C. Temes, Delta-Sigma Data Converters—Theory, Design and Simulation, IEEE Press, New Jersey, 1997). However, varying phase-length effects are also a main focus in this work since they can have a significant impact on the total ADC performance depending on settling accuracy and characteristic. Furthermore, because SC circuits usually operate on a two-phase clock, jitter may give rise to a secondary effect, phase overlap, which does not appear when dealing with a single-phase clock. This effect severely degrades the resolution of a ΣΔ and therefore a thorough understanding of the interaction of jitter on the two phases is necessary. 相似文献
30.
Hannu Ahokas 《Journal of the science of food and agriculture》1978,29(1):47-52
The protein of distal halves of barley kernels or small meal samples was extracted with ethanolic sodium hydroxide solution. After dilution, the protein content was estimated with a spectrophotometer by measurements at 215 and 225 nm. The tryptophan content was estimated from the same extract by a spectrophotofluorimeter. The methods showed high correlations with those used for control. The presented methods can be used in screening kernels in segregating ears or selecting single plants. 相似文献