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Montella A Aria M D'Ambrosio A Galante F Mauriello F Pernetti M 《Accident; analysis and prevention》2011,43(6):2072-2084
Aim of the study was to investigate, by means of a driving simulator experiment, drivers’ behaviour in terms of speed, deceleration, and lateral position on major approaches of rural intersections in relation to different perceptual cues.In the experiment, ten different design conditions with and without speed-reducing treatments along the approach to the intersection were tested. Twenty-three drivers drove a test route two times and data from the second drive were used for comparison. The order of the ten design conditions was counterbalanced for all the drivers to minimize the presentation order effect. Three different data analysis techniques were used: (a) cluster analysis of speed and lateral position data, (b) statistical tests of speed and lateral position data, and (c) categorical analysis of deceleration behaviour patterns.The most effective treatments were the dragon teeth markings (based on the principle of optical road narrowing), the colored intersection area (based on the principle of intersection highlighting), and the raised median island (based on the principle of physical road narrowing). These measures, in comparison to the base intersection, produced: (1) a significant speed reduction starting from 250 m before the intersection in the range between 13 and 23 km/h, (2) a significant change in the deceleration behaviour with a reduction in the proportion of drivers which did not decelerate, and (3) a shift away from the intersection of the deceleration beginning. Given the significant effects on drivers’ behaviour, the dragon teeth markings, the colored intersection area, and the raised median island are strongly recommended for real world implementation. 相似文献
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A case of a mandibular cyst, missing of wall lining and containing some solid material is described. The histologic examination showed that this material consisted of osteofibrous tissue with regressive phenomena, inflammatory cells and hyperplastic nervous tissue. On the basis of clinical and histologic findings it is suggested to be a solitary cyst and the solid material due to a local response to an injury suffered by the patient who is a sport practitioner. 相似文献
34.
Calcium-dependent protein kinases (CDPKs) in plants are characterized by a four-domain structure including conserved sequences in the catalytic domain, and in the C-terminal calmodulin-like domain. Based on this conservation we have PCR-amplified and isolated a potato cDNA clone (StCPK1) from a library representing an early stage of tuber development. DNA sequence analysis revealed that in the catalytic domain, StCPK1 shares more homology with CDPK-related kinases than with CDPKs; however, like CDPKs, it possesses canonical EF-hands at the calmodulin-like 3' end. StCPK1 exists in a few copies in the potato genome and is abundantly expressed in the sepals of mature flowers. Floral expression of genes homologous to StCPK1 appears to be widespread in the family Solanaceae. 相似文献
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An age greater than 60 and diuretic use have been implicated as risk factors for nonsteroidal anti-inflammatory drug (NSAID)-induced decreases in renal function. Misoprostol, a prostaglandin E1 analog, was studied in nine elderly osteoarthritic patients at risk for NSAID-induced renal dysfunction to determine whether it could prevent NSAID-induced renal dysfunction. Subjects received ibuprofen 2400 mg/day and either misoprostol 800 mcg/day or placebo for 14 days in a randomized, double-blinded, crossover trial. Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) studies using inulin and PAH plasma clearance, urinary prostaglandin E2 (PGE2) and protein excretion, and serum electrolytes were obtained at baseline, after the first dose, and on day 7 and 14 of each treatment period. Prostaglandin E2 excretion was significantly reduced after the first dose of ibuprofen and throughout the 14 days in both the misoprostol and placebo treatment groups. No statistically significant differences in GFR, ERPF, protein excretion, serum potassium, or serum sodium were detected between misoprostol and placebo treatment during the 14 days of ibuprofen treatment. However, a subset of two patients who exhibited a decrease of greater than 20% in GFR during placebo treatment, appeared to demonstrate an attenuation of this decline when treated with misoprostol. Effect of time, independent of treatment group, indicated that ERPF was significantly decreased from baseline after the first dose of ibuprofen (P < or = 0.05), whereas GFR was notably diminished from baseline on day 14 only (P < or = 0.05). Misoprostol does not influence GFR and ERPF in unselected subjects purportedly at risk for NSAID-induced renal dysfunction.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Filomena Papa Marco Perugini Sandra Spedaletti 《Behaviour & Information Technology》1998,17(4):187-194
Multimedia Communication Systems (MMCS) are particularly promising for the realization of advanced virtual classroom situations, in which people spatially distributed can communicate in real time using text, voice, sound, still and moving pictures. They could provide the opportunity to improve flexibility of learning and cooperation in the learning team. On the other hand, there is evidence that the availability of MMCS in a distance learning situation does not ensure their use and adoption by the users. Among the barriers to the diffusion of these forms of distance learning, human factors, in particular psychological factors, may play a prominent role. On these topics further theoretical and experimental work is needed. In order to examine these topics a new tool has been implemented at Fondazione Ugo Bordoni (Roma): the distance learning laboratory (DLL). This tool is being utilized in an investigation concerning the use of virtual classroom situation realised using multimedia systems. The present paper is related to the explorative phase of the investigation. In particular its main obectives are: a) to present a pilot study (realised using the DLL) to gain some insights on the psychological variables that can affect performance in virtual classroom situations; b) to propose a Model of Learning through Technological devices (MLT) in a virtual classroom situation. This model has been developed from previous research on computer acceptance, attitudes, social learning, and from the outcomes of our pilot study. 相似文献
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A.M.L. Madureira L.B. Polsky T.A. Burnett B.F. Silper S. Soriano A.F. Sica K.G. Pohler J.L.M. Vasconcelos R.L.A. Cerri 《Journal of dairy science》2019,102(4):3598-3608
The objective of this study was to examine the association between increased physical activity at the moment of timed artificial insemination (AI), detected by an automated activity monitor (AAM), and fertility outcomes. This paper also investigated factors affecting estrous expression in general. A total of 1,411 AI events from 1,040 lactating Holstein cows were recorded, averaging 1.3 ± 0.6 (±standard deviation) events per cow. Activity (measured as steps/h) was monitored continuously by a leg-mounted AAM located on the rear leg of the cow. Ovulation was synchronized by a timed AI protocol based on estradiol and progesterone. Ovarian ultrasonography was performed in all cows on d ?11 (AI = d 0) and in a subset of cows on d 0 (n = 588) and d 7 (n = 819) to determine the presence of a corpus luteum and follicles. The body condition score (1 to 5 scale) was assessed on d 0 and a blood sample was collected for progesterone measurement on d 7. Using the AAM, an estrus event was determined when the relative increase (RI) in physical activity of the cow exceeded 100% of the baseline activity. The physical activity was classified as strong RI (≥300% RI), moderate RI (100–300% RI), or no estrus (<100% RI). Milk production was measured daily and averaged between d ?11 and 0. Pregnancy was diagnosed at 32 and 60 d post-AI and pregnancy losses were calculated. The mean RI at estrus was 328.3 ± 132.1%. Cows with strong RI had greater pregnancy per AI than those with moderate RI and those that did not express estrus (35.1 vs. 27.3 vs. 6.2%). When including only cows that successfully ovulated after timed AI, those that displayed strong intensity RI still had greater pregnancy per AI than those with moderate intensity RI or those that did not express estrus (45.1 vs. 34.8 vs. 6.2%). Cows expressing strong RI at timed AI had greater ovulation rates compared with moderate RI and cows that did not express estrus (94.9 vs. 88.2 vs. 49.5%). Furthermore, pregnancy losses were reduced in cows with strong RI compared with cows expressing moderate RI (13.9 vs. 21.7%). Cows with a strong RI at estrus were more likely to have a corpus luteum at the beginning of the protocol and had greater concentration of progesterone 7 d post-AI. Multiparous cows expressed lower RI compared with primiparous cows. Cows with lower body condition score tended to have decreased RI at estrus. No correlation between estrous expression and pre-ovulatory follicle diameter was observed. Also, no correlation was observed between milk production at AI and RI. In conclusion, strong intensity RI of estrus events at timed AI was associated with improved ovulation rates and pregnancy per AI, and reduced pregnancy losses. These results provide further evidence that measurements of estrous expression can be used to predict fertility at the time of AI and possibly be used as a tool to assist decision making strategies of reproduction programs. 相似文献