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排序方式: 共有170条查询结果,搜索用时 15 毫秒
61.
J Tuomilehto Q Qiao R Salonen A Nissinen JT Salonen 《Canadian Metallurgical Quarterly》1998,21(8):1349-1352
OBJECTIVE: To study the association of ultrasonographic manifestations of common carotid atherosclerosis with glucose intolerance in survivors of the cohort of men born in 1900-1919 in eastern Finland. RESEARCH DESIGN AND METHODS: Carotid ultrasonography was carried out for 182 men in 1989. Glucose tolerance status classified based on an oral glucose tolerance test in 1984 and 1989 surveys was used in both prospective and cross-sectional analyses. RESULTS: Carotid atherosclerosis was common in men aged 70-89 years. There was no significant difference in the maximal carotid intimal-medial thickness between diabetic and nondiabetic men and over different age-groups; it was 1.28, 1.33, and 1.36 mm in subjects with diabetes, impaired glucose tolerance, and normal glucose tolerance, respectively (P = 0.69). No association between the presence of a nonmineralized or a mineralized atherosclerotic lesion with diabetes was found. Fasting plasma insulin did not relate to ultrasonographically detectable atherosclerotic lesions. CONCLUSIONS: Hyperglycemia and hyperinsulinemia may not be main contributors to atherosclerosis in elderly men, partly because smoking is less common and total and LDL cholesterol concentrations are lower in diabetic men than in men with normal glucose tolerance. 相似文献
62.
A major problem in the use of small arrays is the perturbation in the element patterns due to mutual coupling and diffraction effects. The element patterns differ from each other and need to be corrected in order to obtain an array pattern that is close to the desired one. A matrix method can be used to correct the element patterns by modifying the original input/output weights to corresponding weights for corrected elements and vice versa. In this paper the main goal of the array correction is the maximal identity of the element patterns. In addition to identical element patterns the corrected array is characterized by uniform element spacing, which can be chosen to differ significantly from the element spacing in the real array making the corrected array more like a pure virtual array. For the array correction the linear least square error method has been used. To show the applicability of the virtual array, this method is applied to a typical beam scan case, and also over a frequency band. 相似文献
63.
J Kauhanen GA Kaplan DE Goldberg JT Salonen 《Canadian Metallurgical Quarterly》1997,315(7112):846-851
OBJECTIVE: To examine the association between beer binging (regular sessions of heavy beer drinking) and mortality. DESIGN: Prospective population based study with the baseline assessment of level of alcohol intake (dose), by type of drink and drinking pattern, previous and existing diseases, socioeconomic background, occupational status, involvement in organisations during leisure time, physical activity in leisure time, body mass index, blood pressure, serum lipids and plasma fibrinogen concentration, during an average of 7.7 years' follow up of mortality. SETTING: Finland. SUBJECTS: A population sample of 1641 men who consumed beer who were aged 42, 48, 54, or 60 years at baseline. MAIN OUTCOME MEASURES: All cause mortality, cardiovascular mortality, death due to external causes, fatal myocardial infarctions. RESULTS: The risk of death was substantially increased in men whose usual dose of beer was 6 or more bottles per session compared with men who usually consumed less than 3 bottles, after adjustment for age and total alcohol consumption (relative risk 3.01 (95% confidence interval 1.54 to 5.90) for all deaths; 7.10 (2.01 to 25.12) for external deaths; and 6.50 (2.05 to 20.61) for fatal myocardial infarction). The association changed only slightly when smoking, occupational status, previous diseases, systolic blood pressure, low density lipoprotein and high density lipoprotein cholesterol concentration, plasma fibrinogen concentration, body mass index, marital status, leisure time physical activity, and involvement in organisations were controlled for. CONCLUSION: The pattern of beer binging is associated with increased risk of death, independently of the total average consumption of alcoholic drinks. The relation is not explained by known behavioural, psychosocial, or biological risk factors. Death due to injuries and other external causes is overrepresented among beer bingers, but a strong association with fatal myocardial infarction suggests that the pathway may also involve other acute triggers of severe health events. 相似文献
64.
Leppäranta O Vaahtio M Peltola T Zhang D Hupa L Hupa M Ylänen H Salonen JI Viljanen MK Eerola E 《Journal of materials science. Materials in medicine》2008,19(2):547-551
Bioactive glasses (BAGs) of different compositions have been studied for decades for clinical use and they have found many
dental and orthopaedic applications. Particulate BAGs have also been shown to have antibacterial properties. This large-scale
study shows that two bioactive glass powders (S53P4 and 13–93) and a sol–gel derived material (CaPSiO II) have an antibacterial
effect on 17 clinically important anaerobic bacterial species. All the materials tested demonstrated growth inhibition, although
the concentration and time needed for the effect varied depending on the BAG. Glass S53P4 had a strong growth-inhibitory effect
on all pathogens tested. Glass 13–93 and sol–gel derived material CaPSiO II showed moderate antibacterial properties. 相似文献
65.
JP M?kel? R Salmelin M Kotila O Salonen R Laaksonen L Hokkanen R Hari 《Canadian Metallurgical Quarterly》1998,106(5):433-443
The theory of courtship disorder suggests voyeurism, exhibitionism, frotteurism, and preferential rape (a paraphilic preference for coercive sex) are expressions of a common underlying disturbance. Previous research has demonstrated that voyeurism, exhibitionism, and frotteurism are relatively likely to co-occur; however, their associations with rape are weaker. One explanation is that rapists are more heterogeneous and may not always be motivated by a paraphilic interest in coercive sex. Paraphilic interests can be identified using phallometric testing, but the sensitivity of the test is attenuated by voluntary control over erectile responding. Another approach is to look for a behavioral marker associated with paraphilic rape-proneness. Freund (1990) has argued that exhibitionism may be the "hub" of courtship disorder because exposing one's genitals to a stranger is rare in control subjects. We predicted that rapists who also engaged in exhibitionistic activity would be more likely than other rapists to also engage in other expressions of courtship disorder, i.e., voyeurism and frotteurism. To rule out the possibility that rapists who report exhibitionistic activity only differ in their willingness to report anomalous sexual behavior, we also predicted no difference between the groups in their self-reported involvement in other paraphilic activities such as sadism or masochism, or paraphilic target preferences such as fetishism or transvestism. Finally, we predicted no difference between groups in their willingness to admit to attempting or committing rape. The results supported our predictions, and lend credence to the notion of preferential rape as an expression of courtship disorder. Moreover, these results suggest that the presence of another paraphilia, particularly exhibitionism, may be useful as a behavioral marker for paraphilic rape-proneness. 相似文献
66.
Karlos Artto Iiro Kulvik Jarno Poskela Virpi Turkulainen 《International Journal of Project Management》2011,29(4):408-421
This research addresses management control in the front end of innovation projects. We conceptualize and analyze PMOs more broadly than just as a specialized project-focused organizational unit. Building on theories of management control, organization design, and innovation front end literature, we assess the role of PMO as an integrative arrangement. The empirical material is derived from four companies. The results show a variety of management control mechanisms that can be considered as integrative organizational arrangements. Such organizational arrangements can be considered as an alternative to a non-existent PMO, or to complement a (non-existent) PMO's tasks. The paper also contrasts prior literature by emphasizing the desirability of a highly organic or embedded matrix structure in the organization. Finally, we propose that the development path of the management approach proceeds by first emphasizing diagnostic and boundary systems (with mechanistic management approaches) followed by intensive use of interactive and belief systems (with value-based management approaches). The major contribution of this paper is in the organizational and managerial mechanisms of a firm that is managing multiple innovation projects. This research also expands upon the existing PMO research to include a broader management control approach for managing projects in companies. 相似文献
67.
Jarno Salomaa Mika Pulkkinen Kari Halonen 《Analog Integrated Circuits and Signal Processing》2016,89(2):347-356
This paper presents an SC voltage doubler-based voltage regulator for ultra-low power energy harvesting applications. It produces a stable 1.2-V power supply, using inputs from 0.63 to 1.8 V. External compensation and an on-chip output capacitor ensure good performance even with zero load current and any load capacitance. The regulator tolerates arbitrary input ramp-ups, and is immune to blackout and brownout. A stability analysis for the regulator control loop is presented. The regulator ASIC is implemented in a 180 nm CMOS process. The measured regulator peak power and current efficiency are 63 and 49 %, respectively. The performance has been characterized with load currents from zero to \(100\,\upmu\)A. 相似文献
68.
The aim of this paper is to show the special characteristics of the indoor environment related to radio propagation and furthermore
to radio network planning. The aspects of the radio network planning are highlighted especially for Wideband Code Division
Multiple Access (WCDMA) radio access technology that is used widely in the third generation mobile networks. Moreover, the
detailed planning parameters in indoor environment are studied for High Speed Downlink Packet Access (HSDPA) in order to support
high throughput data applications in Universal Mobile Telecommunications System (UMTS). The final target of the paper is to
compare pico cell, distributed antenna system (DAS), and radiating cable network configurations in indoor environment to provide
the optimal radio conditions for the data applications, and thus to serve highest number of mobile users. Several measurement
campaigns with different antenna configurations have been conducted in order to study the effect of multi path related parameters,
as delay spread of the signal. Also other capacity related parameters as received signal levels, interference, throughput,
and transmit power levels have been studied in order to find out the optimal solution for HSDPA in UMTS. The results clearly
show that pico cells and distributed antenna system have outstanding performance in indoor propagation channel compared to
radiating cable. In sense of signal quality, pico cell performance is slightly better compared to distributed antenna system.
However, measurements with HSDPA indicate that practical capacity of DAS outperforms pico cells. The measurements also show
that separation of the antennas is a key capacity related parameter when planning WCDMA based indoor systems. 相似文献
69.
Komulainen M. Berg M. Jantunen H. Salonen E.T. Free C. 《Antennas and Propagation, IEEE Transactions on》2008,56(4):944-950
A novel method is presented for electrically tuning the frequency of a planar inverted-F antenna (PIFA). A tuning circuit, comprising an RF switch and discrete passive components, has been completely integrated into the antenna element, which is thus free of dc wires. The proposed tuning method has been demonstrated with a dual-band PIFA capable of operating in four frequency bands. The antenna covers the GSM850, GSM900, GSM1800, PCS1900 and UMTS frequency ranges with over 40% total efficiency. The impact of the tuning circuit on the antenna's efficiency and radiation pattern have been experimentally studied through comparison with the performance of a reference antenna not incorporating the tuning circuit. The proposed frequency tuning concept can be extended to more complex PIFA structures as well as other types of antennas to give enhanced electrical performance. 相似文献
70.
This study examined the directly attached cells (DAT cells) of the human junctional epithelium from teeth extracted for advanced periodontal disease. The monolayer nature of the DAT cells remaining on the tooth surface after extraction offers a unique opportunity to study their morphology and activity in situ. We collected DAT cells and examined them by transmission electron microscopy and by autoradiography of cells labeled with 3H-thymidine. Our morphological results suggest that degenerative changes associated with pocket formation affect individual cells rather than regions of the DAT cell population at one time. The epithelial attachment apparatus (EAA) appeared to be the most resistant structure persisting on the tooth surface during the degeneration of the individual DAT cells. The new technique developed for two-dimensional observation of the sheet of DAT cells labeled in situ on the tooth surface in culture showed that the attached cells, even in periodontal disease, exhibit proliferative ability, suggesting a regenerative role for the DAT cells. 相似文献