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51.
Although there is an ever-increasing discussion on governance in recent project research, the concept of project governance and its main origins remains ambiguous. In this paper, we examine project governance literature and contrast it to general governance literature published outside the domain of project research. Our analysis revealed the existence of two distinct and relatively independent streams of research. One of these streams addresses project governance as a phenomenon external to any specific project, while the other views project governance as internal to a specific project. Our results further indicate that while project governance literature bases most of its argumentation on established project research it also, to a significant extent, draws from the transaction cost economics literature. Based on our findings, we argue that there exists considerable potential for bridging project governance literature and general governance literature further.  相似文献   
52.
We have developed a compact short focal distance Bent Crystal Laue Analyzer (BCLA) for Cu speciation studies of biological systems with specific applications to cancer biology. The system provides high energy resolution and high background rejection. The system is composed of an aluminum block serving as a log spiral bender for a 15 micron thick Silicon 111 crystal and a set of soller slits. The energy resolution of the BCLA-about 14 eV at the Cu Kα line- allows resolution of the Cu Kα(1) and CuKα(2) lines. The system is easily aligned by using a set of motorized XYZ linear stages. Two operation modes are available: incident energy scans (IES) and emission energy scans (EES). IES allows scanning of the incident energy while the BCLA system is maintained at a preselected fixed position--typically CuKα(1) line. EES is used when the incident energy is fixed and the analyzer is scanned to provide the peak profile of the emission lines of Cu.  相似文献   
53.
Four cultivars of red beetroot (Beta vulgaris) were evaluated with respect to their betalain and phenolic contents. The compounds were analysed using HPLC and identified by HPLC-DAD, HPLC-ESI-MS and NMR techniques. Betalains (vulgaxanthins I and II, betanin and isobetanin) and phenolics [5,5',6,6'-tetrahydroxy-3,3'-biindolyl, feruloylglucose and #-D-fructofuranosyl-!-D-(6-O-(E)-feruloylglucopyranoside)] were determined in different parts of the root; betalains were analysed separately in the water extract and phenolics in the fractionated 80% aqueous methanol extract (betalain-free water fraction). In each cultivar, both betanin and isobetanin were found in greater amounts in the peel than in the flesh. A similar trend was not observed in the distribution of vulgaxanthins. The three studied phenolics appeared in all root parts of the beetroot cultivars with the flesh generally containing the least content. Additionally, two phenolic amides (N-trans-feruloyltyramine and N-trans-feruloylhomovanillylamine) and four flavonoids (betagarin, betavulgarin, cochliophilin A and dihydroisorhamnetin) were detected in the fractionated 80% aqueous methanol peel extracts (acetonitrile fraction) of beetroot.  相似文献   
54.
OBJECTIVE: To determine the acute injury profile in each of six sports and compare the injury rates between the sports. DESIGN: Analysis of national sports injury insurance registry data. SETTING: Finland during 1987-91. SUBJECTS: 621,691 person years of exposure among participants in soccer, ice hockey, volleyball, basketball, judo, or karate. MAIN OUTCOME MEASURES: Acute sports injuries requiring medical treatment and reported to the insurance company on structured forms by the patients and their doctors. RESULTS: 54,186 sports injuries were recorded. Injury rates were low in athletes aged under 15, while 20-24 year olds had the highest rates. Differences in injury rates between the sports were minor in this adult age group. Overall injury rates were higher in sports entailing more frequent and powerful body contact. Each sport had a specific injury profile. Fractures and dental injuries were most common in ice hockey and karate and least frequent in volleyball. Knee injuries were the most common cause of permanent disability. CONCLUSIONS: Based on the defined injury profiles in the different sports it is recommended that sports specific preventive measures should be employed to decrease the number of violent contacts between athletes, including improved game rules supported by careful refereeing. To prevent dental injuries the wearing of mouth guards should be encouraged, especially in ice hockey, karate, and basketball.  相似文献   
55.
Extracellular field potential (FP) recordings with microelectrode arrays (MEAs) from cardiomyocyte cultures offer a non-invasive way of studying the electrophysiological properties of these cells at the population level. Several studies have examined the FP properties of cardiomyocytes of various origins, including stem cell-derived cardiomyocytes. This focus reflects growing importance and interest in the field of MEA. High-quality cardiac FP signals are often difficult to obtain, especially from stem cell-derived cardiomyocyte cultures, which represent an important new field in cardiac electrophysiology. One way to improve the quality of these recordings is to average the cardiac FP signals. To date, however, no studies have examined the effect of averaging on cardiac FP signals. We report here that cardiac FP averaging can yield higher-quality signals than original individual FPs, and therefore promise more accurate detection of different phases and analysis of the cardiac FP signal. Averaged signals improved the signal-to-noise ratio (SNR), and obtaining reliable averages required approximately 50 cardiac cycles. We therefore propose that routine cardiac FP averaging can serve as a tool to compare the effects of different experimental conditions or stimuli on the properties of cardiac FPs.  相似文献   
56.
57.
We studied whether left ventricular (LV) mass and concentricity [relative myocardial volume (RMV)] are associated with exercise blood pressure (BP) in athletes. LV structure and filling were evaluated by Doppler echocardiography and BP in maximal bicycle ergometry and isometric handgrip tests on 32 male endurance athletes and 15 age-matched controls. Indexed LV mass was 145 +/- 14 (SD) g/m in athletes and 93 +/- 20 g/m in controls. Mass was not associated with BP at rest or in low-grade exercise, but with heavier exercise loads this association strengthened in athletes, being maximal at peak exercise (r = 0.65 for mass and 0.58 for indexed mass; P < 0.001). Multivariate analysis indicated that BP at peak exercise accounted for 34% and the amount of training for an additional 11% of the variance in indexed LV mass. RMV was 21% larger in athletes. Only the increase in systolic BP during handgrip explained significantly (19%) the variance in RMV. LV filling velocities were not associated with mass, RMV, or BP. We conclude that in endurance athletes LV mass is associated with BP in heavy dynamic exercise and LV concentricity with BP response in static exercise.  相似文献   
58.
Appropriate intraluminal microenvironment in the epididymis is essential for maturation of sperm. To clarify whether the anion transporters SLC26A2, SLC26A6, SLC26A7, and SLC26A8 might participate in generating this proper intraluminal milieu, we studied the localization of these proteins in the human efferent and the epididymal ducts by immunohistochemistry. In addition, immunohistochemistry of several SLC26-interacting proteins was performed: the Na(+)/H(+) exchanger 3 (NHE3), the Cl(-) channel cystic fibrosis transmembrane conductance regulator (CFTR), the proton pump V-ATPase, their regulator Na(+)/H(+) exchanger regulating factor 1 (NHERF-1), and carbonic anhydrase II (CAII). Our results show that SLC26A6, CFTR, NHE3, and NHERF-1 are co-expressed on the apical side of the nonciliated cells, and SLC26A2 appears in the cilia of the ciliated cells in the human efferent ducts. In the epididymal ducts, SLC26A6, CFTR, NHERF-1, CAII, and V-ATPase (B and E subunits) were co-localized to the apical mitochondria rich cells, while SLC26A7 was expressed in a subgroup of basal cells. SLC26A8 was not found in the structures studied. This is the first study describing the localization of SLC26A2, A6 and A7, and NHERF-1 in the efferent and the epididymal ducts. Immunolocalization of human CFTR, NHE3, CAII, and V-ATPase in these structures differs partly from previous reports from rodents. Our findings suggest roles for these proteins in male fertility, either independently or through interaction and reciprocal regulation with co-localized proteins shown to affect fertility, when disrupted.  相似文献   
59.
A novel tuning-fork test method was developed to study hydrogen-induced stress corrosion cracking of high-strength steels. Special tuning-fork specimens are designed to enable accurate stress adjustment via constant displacement under cathodic hydrogen charging conditions. In this study, the testing method is further developed, making the potentiostatic hydrogen charging possible through the modifications of the corrosion cell. Different direct-quenched, low- and medium-carbon steel grades, with a hardness range of 300–550 HBW, are investigated with both galvanostatic and potentiostatic hydrogen charging techniques. For each steel grade, the lowest fracture stress and highest no-fracture stress are determined. Both hydrogen charging techniques produce similar results, and it is observed that the fracture stress decreases with the increase in hardness. However, the potentiostatic technique produces larger differences between the lowest fracture stress results, thus having a better resolution.  相似文献   
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