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11.
Wolter Marc Tedjo-Palczynski Irene Hentschel Bernd Kuhlen Torsten 《Computer Graphics and Applications, IEEE》2009,29(6):54-64
Scientific-visualization tools can make time-varying simulations easier to understand. The growing efficiency of today's high-performance computers enables simulation of physical phenomena with a high temporal resolution. Consequently, visualization systems require efficient navigation in the temporal dimension. This 3D user interface employs direct-manipulation metaphors for temporal navigation in scientific visualizations. By interacting with objects using their 3D trajectory, users can navigate in time by specifying spatial inputs. This article is part of a special issue on 3D user interfaces. 相似文献
12.
A sample of 42 case notes of alcoholic patients were abstracted for 17 items by three different raters. Interrater agreement was generally rather low. Research based on case-note abstraction which does not report on abstraction reliabilities must therefore be viewed with some suspicion. It would be helpful if clinical material could more often be collected in a standardized manner. 相似文献
13.
A series of 100 therapeutic abortions by vaginal hysterotomy is reported. This method of vaginal hysterotomy with a transverse low segment incision just above the internal os of the cervix was first described by Fuchs in 1939. The important advantage of this method is complete avoidance of the uterine cervix. With this method a therapeutic abortion after the tenth week of gestation and in a few cases, up to the 20th week of gestation can be accomplished by a fast one stage technique with few side effects. The method is considered to be superior to the injection methods and the two stage procedures. With skill in vaginal operative techniques, this method can be used in any gynaecological department as a routine method. In this series, 28 cases had concomitant tubal ligations. There were two subsequent pregnancies. Complications were one uterine perforation during the curettage requiring laparotomy and suture. There was one laceration of the trigon of the bladder requiring suture. There were 2 cases of hemorrhage. There were 6 inflammatory reactions in the perimetria of which two required administration of antibiotics. There was superficial thrombophlebitis in one case. And there was a severe coagulation defect in one case of a missed abortion at 5 months gestation. 相似文献
14.
The creep behaviour of Sn96.5Ag3.5- and Sn95.5Ag3.8Cu0.7-solder was studied specifically for its dependence on technological and environmental factors. The technological factors considered were typical cooling rates and pad metallizations for solder joints in electronic packaging. The environmental factors included microstructural changes as a result of thermal aging of solder joints. Creep experiments were conducted on three types of specimens—flip–chip joints, PCB solder joints and bulk specimens. flip–chip specimens were altered through the selection of various under bump metallizations (Cu vs. NiAu), cooling rates (40 K/min vs. 120 K/min), and thermal storage (24 h, 168 h, and 1176 h at 125 °C). PCB solder joints were studied by using a copper pin soldered into a thru-hole connection on a printed circuit board having a NiAu metallization. Bulk specimens contained the pure alloys. The creep behaviour of the SnAg and SnAgCu solders varied in dependence of specimen type, pad metallization and aging condition. Constitutive models for SnAg and SnAgCu solders as they depend on the reviewed factors are provided. 相似文献
15.
X. Q. Zhou G. C. Cho U. Lemmer W. Kü tt K. Wolter H. Kurz 《Solid-state electronics》1989,32(12):1591-1595
Hot carrier relaxation in InP and GaAs is investigated in a comparative study using three different time resolved optical techniques. At carrier densities between 1017 to 1018 cm−3 in both materials the relaxation is strongly influenced by carrier-carrier-scattering. Internal thermalization of electrons and holes occurs on a femtosecond time scale comparable to the duration of the excitation. The temperatures of electrons and holes, however, remain different on a time scale of picoseconds. 相似文献
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A 26-year-old man sustained a C2 arc fracture. Ventral spondylodesis using an H-plate was performed. The patient developed a pharyngovertebral fistula which remained undetected for 1 year. Spontaneous fusion of C3/C4 and osteolysis of the cortical block occurred. The fistula was demonstrated intraoperatively and the implant was transorally removed. No further problems occurred after this unusual method of treatment. The anatomy of the cervical spine, special problems of intensive care patients and the use of proper instrumentation are discussed. 相似文献
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19.
Homoserine Lactones,Methyl Oligohydroxybutyrates,and Other Extracellular Metabolites of Macroalgae‐Associated Bacteria of the Roseobacter Clade: Identification and Functions
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Lisa Ziesche Hilke Bruns Marco Dogs Laura Wolter Florian Mann Prof. Irene Wagner‐Döbler Prof. Dr. Thorsten Brinkhoff Prof. Stefan Schulz 《Chembiochem : a European journal of chemical biology》2015,16(14):2094-2107
Twenty‐four strains of marine Roseobacter clade bacteria were isolated from macroalgae and investigated for the production of quorum‐sensing autoinducers, N‐acylhomoserine lactones (AHLs). GC/MS analysis of the extracellular metabolites allowed us to evaluate the release of other small molecules as well. Nineteen strains produced AHLs, ranging from 3‐OH‐C10:0‐HSL (homoserine lactone) to (2E,11Z)‐C18:2‐HSL, but no specific phylogenetic or ecological pattern of individual AHL occurrence was observed when cluster analysis was performed. Other identified compounds included indole, tropone, methyl esters of oligomers of 3‐hydroxybutyric acid, and various amides, such as N‐9‐hexadecenoylalanine methyl ester (9‐C16:1‐NAME), a structural analogue of AHLs. Several compounds were tested for their antibacterial and antialgal activity on marine isolates likely to occur in the habitat of the macroalgae. Both AHLs and 9‐C16:1‐NAME showed high antialgal activity against Skeletonema costatum, whereas their antibacterial activity was low. 相似文献
20.
Predictors of smoking cessation among elderly smokers treated for nicotine dependence 总被引:2,自引:0,他引:2
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L. C. Dale D. A. Olsen C. A. Patten D. R. Schroeder I. T. Croghan R. D. Hurt K. P. Offord T. D. Wolter 《Tobacco control》1997,6(3):181-187
OBJECTIVE: To examine outcomes and predictors of smoking cessation among elderly patients treated for nicotine dependence. DESIGN: Retrospective analysis of patients aged 65-82 who received a nicotine dependence consultation at the Mayo Medical Center between 1 April 1988 and 30 May 1992. Patients were contacted by telephone by a trained interviewer six months after the consultation and were sent a follow-up survey in August 1993. SETTING: Mayo Medical Center, Rochester, Minnesota, United States. SUBJECTS: A total of 613 patients (310 men, 303 women) with a mean age of 69.0 (SD 3.5) years were seen during the study period. MAIN OUTCOME MEASURES: Point prevalence self-reported smoking status. Patients were considered abstinent if they self- reported not smoking (not even a puff) during the seven days before contact. RESULTS: At six-month follow up, 24.8% of the 613 patients reported abstinence from smoking. On multivariate analysis, smoking abstinence was more likely if patients were hospitalised at the time of the consultation, married to a non-smoking spouse, very motivated to stop smoking, and reported their longest time of previous abstinence to be less than a day or more than a month. The response rate to the mailed follow-up survey was 69.9% (429 of 613). The mean duration of follow up was 40.0 +/- 13.2 months following the consultation. Of the 429 patients, 103 (24.0%) reported abstinence from smoking and 326 (76.0%) were smoking at six-month follow up. Patients who reported abstinence at six months had a higher cessation rate at the last follow up (76.0%) compared with patients who were smoking at six-month follow up (33.0%, P < 0.001). For patients who were not smoking at six months, no factors were found to significantly predict abstinence at last follow up. For patients who were smoking at six months, factors associated with smoking cessation at last follow up were: more than a year as the longest time off cigarettes before the consultation; counsellor rating of less severe nicotine dependence; and older age at first regular smoking. CONCLUSIONS: Several predictors of smoking cessation were identified in this study which may be useful for tailoring smoking interventions for the elderly.
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