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1.
E. KOCIANOVA MSc Ing R. J. FOOT C. F. FORSTER BSc PhD CE FIChemE 《Water and Environment Journal》1992,6(4):342-350
The presence of stable foams can seriously impair the ability of an activated sludge to produce a high-quality effluent. This paper examines how the physicochemical characteristics of the solids are related to foam formation and describes how the foaming potential of full-scale plants can be assessed. It also confirms that Microthrix parvicella can exhibit a variable morphology and shows that these variations are related to the physicochemical properties that characterize foam-forming solids. 相似文献
2.
Alexander J. C. Kuehne Markus Kaiser Allan R. Mackintosh Bodo H. Wallikewitz Dirk Hertel Richard A. Pethrick Klaus Meerholz 《Advanced functional materials》2011,21(13):2564-2570
The metastable β‐phase morphology, inherent to most polyfluorene homo‐polymers, is of interest due to its superior optical and electrical characteristics compared to its amorphous analogue. Here, a polyfluorene with vinyl‐ether‐functionalized aliphatic side‐chains that allow crosslinking is reported. It is demonstrated that the previously induced conformational morphology is preserved in the resulting polyfluorene network, which enables subsequent wet thin‐film processing. Electron‐beam lithography provides a means for sub‐(optical)‐wavelength patterning of the crosslinkable polyfluorene films. As a specific demonstration, optically‐pumped distributed‐feedback (DFB) lasers made from surface‐relief gratings in amorphous and β‐phase polyfluorene are presented. By backfilling gratings of one morphology by the other, devices are demonstrated that exhibit lasing at two wavelengths with a threshold (<1 μJ cm?2) at least an order of magnitude lower compared with previous data. 相似文献
3.
The case for integrated land-use and transport strategies for Australian cities is evaluated with particular reference to sustainabliity and equity values. The potential to apply such a strategy to Adelaide is explored. It is concluded that there are sufficient mainly broadacre government-owned consolodation opportunities adjoining the spinal rail network to accomodate the city's forecast population growth over the next 20 years. A mutually reinforcing program of investment in rail infrastructure and rail-oriented urban village developments is proposed. 相似文献
4.
SR Dager ME Layton W Strauss TL Richards A Heide SD Friedman AA Artru CE Hayes S Posse 《Canadian Metallurgical Quarterly》1999,156(2):229-237
OBJECTIVE: Since there is limited information concerning caffeine's metabolic effects on the human brain, the authors applied a rapid proton echo-planar spectroscopic imaging technique to dynamically measure regional brain metabolic responses to caffeine ingestion. They specifically measured changes in brain lactate due to the combined effects of caffeine's stimulation of glycolysis and reduction of cerebral blood flow. METHOD: Nine heavy caffeine users and nine caffeine-intolerant individuals, who had previously discontinued or substantially curtailed use of caffeinated products because of associated anxiety and discomforting physiological arousal, were studied at baseline and then during 1 hour following ingestion of caffeine citrate (10 mg/kg). To assess state-trait contributions and the effects of caffeine tolerance, five of the caffeine users were restudied after a 1- to 2-month caffeine holiday. RESULTS: The caffeine-intolerant individuals, but not the regular caffeine users, experienced substantial psychological and physiological distress in response to caffeine ingestion. Significant increases in global and regionally specific brain lactate were observed only among the caffeine-intolerant subjects. Reexposure of the regular caffeine users to caffeine after a caffeine holiday resulted in little or no adverse clinical reaction but significant rises in brain lactate which were of a magnitude similar to that observed for the caffeine-intolerant group. CONCLUSIONS: These results provide direct evidence for the loss of caffeine tolerance in the human brain subsequent to caffeine discontinuation and suggest mechanisms for the phenomenon of caffeine intolerance other than its metabolic effects on elevating brain lactate. 相似文献
5.
CE Hotchkiss 《Canadian Metallurgical Quarterly》1999,24(2):101-107
BACKGROUND AND METHODS: Laboratory, clinical, and epidemiologic evidence suggests that calcium may help prevent colorectal adenomas. We conducted a randomized, double-blind trial of the effect of supplementation with calcium carbonate on the recurrence of colorectal adenomas. We randomly assigned 930 subjects (mean age, 61 years; 72 percent men) with a recent history of colorectal adenomas to receive either calcium carbonate (3 g [1200 mg of elemental calcium] daily) or placebo, with follow-up colonoscopies one and four years after the qualifying examination. The primary end point was the proportion of subjects in whom at least one adenoma was detected after the first follow-up endoscopy but up to (and including) the second follow-up examination. Risk ratios for the recurrence of adenomas were adjusted for age, sex, lifetime number of adenomas before the study, clinical center, and length of the surveillance period. RESULTS: The subjects in the calcium group had a lower risk of recurrent adenomas. Among the 913 subjects who underwent at least one study colonoscopy, the adjusted risk ratio for any recurrence of adenoma with calcium as compared with placebo was 0.85 (95 percent confidence interval, 0.74 to 0.98; P=0.03). The main analysis was based on the 832 subjects (409 in the calcium group and 423 in the placebo group) who completed both follow-up examinations. At least one adenoma was diagnosed between the first and second follow-up endoscopies in 127 subjects in the calcium group (31 percent) and 159 subjects in the placebo group (38 percent); the adjusted risk ratio was 0.81 (95 percent confidence interval, 0.67 to 0.99; P=0.04). The adjusted ratio of the average number of adenomas in the calcium group to that in the placebo group was 0.76 (95 percent confidence interval, 0.60 to 0.96; P=0.02). The effect of calcium was independent of initial dietary fat and calcium intake. CONCLUSIONS: Calcium supplementation is associated with a significant - though moderate - reduction in the risk of recurrent colorectal adenomas. 相似文献
6.
葛思华 《Canadian Metallurgical Quarterly》2011,20(3)
焦点解决短期心理辅导咨询的理论近年来广受关注,运用这一理论解决大学新生适应性问题具有很强的实用价值.在厘清焦点解决短期心理咨询基本理念的基础上,探索其适用的范围,研究运用过程的有关实务,以及实践过程中需要注意和整合的问题,使得大学新生心理辅导更富效率. 相似文献
7.
OBJECTIVE: To propose a definition for stage IA1 cervical adenocarcinoma, based on the International Federation of Gynecology and Obstetrics (FIGO) staging system, and to determine if patients meeting criteria might be candidates for conservative surgery. METHODS: Two hundred women were diagnosed with early-stage cervical adenocarcinoma from 1982 to 1996. Histopathologic sections were reviewed by a gynecologic pathologist. Medical records were reviewed, and patients included in this study had microscopically identifiable lesions, up to 3 mm invasive depth, up to 7 mm tumor width, and negative margins if cone biopsy was performed. RESULTS: Twenty-one patients with microinvasive adenocarcinoma met criteria for FIGO stage IA1 carcinoma of the cervix. The median (range) follow-up was 76 (30-172) months and median (range) patient age was 38 (24-75) years. Definitive treatment included type II or III radical hysterectomy in 16 cases, simple abdominal or vaginal hysterectomy in four cases, and loop electrosurgical excision procedure in one case; one patient received adjuvant pelvic radiation. The histologic subtypes were endocervical adenocarcinoma in 18 cases, adenosquamous carcinoma in two cases, and clear-cell adenocarcinoma in one case. There was no evidence of parametrial invasion or lymph node metastases in any patient who had radical surgery, and there were no disease recurrences. CONCLUSION: Patients with microinvasive adenocarcinoma who met criteria for FIGO stage IA1 cervical carcinoma had disease limited to the cervix, and conservative surgery, such as cone biopsy or simple hysterectomy, might offer them definitive treatment. 相似文献
8.
Testicular involvement by sarcoidosis is rare. We report a case of a patient with known sarcoid who had a unilateral testicular nodule with apparent capsular invasion on sonography. The epididymis was normal on both sides. Despite these atypical features, pathology showed the nodule to be a sarcoid granuloma. In patients with sarcoidosis, the differential diagnosis of an intratesticular mass should include testicular involvement by sarcoid. 相似文献
9.
Basak AK; Kroone RC; Lubsen NH; Naylor CE; Jaenicke R; Slingsby C 《Protein engineering, design & selection : PEDS》1998,11(5):337-344
The 2-domain gammaS-crystallin, a highly conserved early evolutionary
off-shoot of the gamma-crystallin family, is located in the water-rich
region of eye lenses. The expressed C-terminal domain, gammaS-C, has been
crystallized and the 2.56 A X-ray structure determined. There are two
domains in the asymmetric unit which pair about a distorted twofold axis.
One of the domains has an altered conformation in a highly conserved region
of the protein, the tyrosine corner. The distorted gammaS-C dimer of
domains is compared with the highly symmetrical, equivalent recombinant
dimer of C-terminal domains from gammaB- crystallin. Sequence changes close
to the interface, that distinguish gammaS from the other gamma-crystallins,
are examined in order to evaluate their role in symmetrical domain pairing.
相似文献
10.