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21.
Since the 1950s, digital games in Finland have bridged gaps between professional users and the public as well as institutional and domestic environments. The early significance of Finland's 1970s and 1980s computer games hobbyist and hacker cultures is still evident: clear connections exist between the country's rich history of such subcultures and its modern international success in multimedia and mobile entertainment.  相似文献   
22.
In infrared spectroscopy human hair has normally been studied using attenuated total reflectance or diffuse reflectance infrared Fourier transform spectroscopy, for which the sample preparation methods can lead to problems of reproducibility. Definite information could be obtained by studying intact individual hair fibers, but the small diameter of hair fibers and the lack of sensitivity make such measurement difficult. A highly detailed infrared spectrum of human hair has been measured using a cantilever-based photoacoustic detection. The spectrum can be obtained even if a piece of hair as small as 1 cm is used as a sample. Photoacoustic spectroscopy (PAS) is a well-established technique in many areas, but very little has been published in the research of proteins. Two simple applications of PAS for human hair, as well as measurements with different types of proteins, are presented in this paper.  相似文献   
23.
The aim of the study was to examine whether smoking reduction over a 6-year period (1975-1981) predicted smoking cessation 9 years later by 1990. The longitudinal data from three surveys over 15-year period among the Finnish adult twin cohort were used. The data were collected by postal surveys in 1975, 1981, and 1990, and the sample comprised 11,015 participants, of whom 2,443 were persistent current smokers in 1975 and 1981. Smoking cessation by 1990 was examined as the outcome measure. Nineteen percent reported having stopped smoking by 1990, corresponding to an approximate annual rate of smoking cessation of 2%. Those who had quit smoking by 1990 had larger decreases in smoking between 1975 and 1981. The odds ratio for quitting by 1990 increased with increasing levels of reduction in amount smoked between 1975 and 1981. This was found in both categorical and trend analyses, and when adjusting for age, sex and for amount of baseline smoking. The model among twin pairs discordant for cessation indicated that the association of smoking reduction with increased likelihood of cessation was independent of genetic or early shared family influences on smoking behavior. We conclude that smokers who are able to decrease the number of cigarettes smoked per day by at least 25% are more likely to quit later.  相似文献   
24.
Elevated temperatures (52, 60 and 65 °C) were used to enrich hydrogen producers on cellulose from cow rumen fluid. Methanogens were inhibited with two different heat treatments. Hydrogen production was considerable at 60 °C with the highest H2 yield of 0.44 mol-H2 mol-hexose−1 (1.93 mol-H2 mol-hexose-degraded−1) as obtained without heat treatment and with acetate and ethanol as the main fermentation products. H2 production rates and yields were controlled by cellulose degradation that was at the highest 21%. The optimum temperature and pH for H2 production of the rumen fluid enrichment culture were 62 °C and 7.3, respectively. The enrichments at 52 and 60 °C contained mainly bacteria from Clostridia family. At 52 °C, the bacterial diversity was larger and was not affected by heat treatments. Bacterial diversity at 60 °C remained similar between heat treatments, but decreased during enrichment. At 60 °C, the dominant microorganism was Clostridium stercorarium subsp. leptospartum.  相似文献   
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26.
This paper presents a new index assignment (IA) method when vector quantization indices are transmitted over a particular class of Markov binary channels, namely the finite-memory contagion channels. (See F. Alajaji and T. Fuja, IEEE Trans. Inform. Theory, 40:2035-2041, 1994.) For this class of binary channels, the Hadamard transform of the vector formed with noise pattern probabilities obeys well-structured recursions, allowing an efficient evaluation of the channel distortion and also revealing a useful approximation based on the dominant terms in the channel distortion expression. The proposed IA method minimizes the distortion approximation and is very robust to changes in the parameters of the channel model. The same technique applies for both maximum likelihood and mean-squared error decoding methods. The IA algorithm is applied to the transmission of line spectral frequency parameters quantized as in the G.729 standard to show the usefulness of the proposed method.  相似文献   
27.
Similarities for Extraversion (E) and Neuroticism (N) scale scores from the Eysenck Personality Inventory were evaluated in 7,144 adult twin pairs, drawn from the population-based Finnish Twin Cohort, as a function of the co-twins' genetic resemblance, gender, age, and the frequency of their social interaction with each other. To separate effects of shared genes from those of shared experience, we performed hierarchical multiple regressions of double-entry data matrices. Results establish the predictive significance of both genetic and experiential influences: Genetic effects remained significant when tested after the effects of social contact were first removed; conversely, for N scores, the effects of social contact remained significant when assessed after genetic influences were first removed. These findings establish genetic variance in major dimensions of adult personality but assign a significant role to common experience as well. The first finding constructively replicates reports by others; the second challenges the widespread assumption that shared experiences have a negligible impact on sibling similarity in adult personality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
28.
In this paper a piezoelectric energy harvester based on a Cymbal type structure is presented. A piezoelectric disc ?35?mm was confined between two convex steel discs ?35?mm acting as a force amplifier delivering stress to the PZT and protecting the harvester. Optimization was performed and generated voltage and power of the harvester were measured as functions of resistive load and applied force. At 1.19?Hz compression frequency with 24.8?N force a Cymbal type harvester with 250?μm thick steel discs delivered an average power of 0.66?mW. Maximum power densities of 1.37?mW/cm3 and 0.31?mW/cm3 were measured for the piezo element and the whole component, respectively. The measured power levels reported in this article are able to satisfy the demands of some monitoring electronics or extend the battery life of a portable device.  相似文献   
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30.

Wireless connectivity has become a significant part of human life all over the world, both in developing and developed countries. In order to provide sufficient coverage without the densification of cellular networks, relatively low carrier frequencies should be used. This paper considers the reuse of the digital terrestrial television (DTT) band for cellular system operation in Kenya, while protecting incumbent TV signal reception according to the Dynamic Spectrum Alliance (DSAL) rules. A state of the art model for DTT coverage and allowed cellular system power calculation is tested using real data for Kenya. Suggestions regarding future DSAL rules amendments are provided. Moreover, the amount of spectrum resources available for cellular system operation in the DTT band in Kenya is estimated against varying system parameters.

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