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121.
The possibility of using neural networks for modelling instrumental-sensory relationships is investigated. The advantages and disadvantages of using artificial neural networks (ANNs) are considered and compared with those of the multivariate linear methods of principal components regression (PCR) and partial least squares regression (PLS). In particular the problem of modelling nonlinear relationships is considered. It is concluded that ANNs cannot replace PCR and PLS for linear relationships but do offer potential for modelling nonlinear relationships. 相似文献
122.
Murat Eyvaz Mustafa Kirlaroglu Tugrul Selami Aktas Ebubekir Yuksel 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2009,153(1-3):16-22
The main goal of this study is to investigate the effects of alternating current (AC) on dye removal from aqueous solutions by electrocoagulation (EC). An EC system with parallel-connected aluminium electrodes was operated in batch mode. Two different aqueous dye solutions were used: one was obtained from Dianix Yellow CC (DY) and the other was obtained using Procion Yellow (PY). The experiments employing direct current (DC) were carried out using a DC power supply. The AC experiments were conducted using rectangular wave, which is produced with an adjustable time relay connected to the output of DC power supply. This current is called alternating pulse current (APC) in order to refer AC system in this study. Total organic carbon (TOC) and dye removal efficiencies were measured to assess treatment efficiency. Operating cost was calculated for both power supply systems and alternating pulse current was found superior to direct current for the treatment of reactive and disperse dyes used in this study. 相似文献
123.
B Danielsen IJ S?rensen M Nybo EH Nielsen B Kaplan SE Svehag 《Canadian Metallurgical Quarterly》1997,1339(1):73-78
It has been found that sphingosine and sphingosylphosphorylcholine (amphiphilic cations) have a stimulatory, and cholesterol 3-sulfate (an amphiphilic anion), an inhibitory, effect on [14C]serine incorporation into phosphatidylserine in glioma C6 and rat liver microsomes. In glioma intact cells sphingosine stimulates phosphatidylserine synthesis in a process independent of protein kinase C, but suppressed by thapsigargin. We suggest that the stimulation of the enzyme occurs by the interaction of amphiphilic cations with the membrane cosubstrate phospholipids, leading to a charge redistribution on their phosphate groups, and hence facilitating the enzyme action. A new hypothesis concerning the mechanism of the serine base exchange reaction is discussed. 相似文献
124.
125.
J Kaplan 《Canadian Metallurgical Quarterly》1997,149(10):374-378
Autonomy is a crucial, yet litigious right in health care that is usually unquestioned in the case of adults. However, children's or their guardian's refusal to accept necessary medical care can expedite the question of autonomy from the medical to the legal arena. Therefore, to save time, money, and lives, the health care establishment, specifically ethics committees, must be given rights as a judicial body to hand down binding judgments in cases of minors refusing the medical community's standard of care. 相似文献
126.
LS Palmer GJ Andros M Maizels WE Kaplan CF Firlit 《Canadian Metallurgical Quarterly》1997,49(4):604-608
OBJECTIVES: To evaluate the management approach for vesicoureteral reflux (reflux) into a solitary kidney. METHODS: Outcomes of all children with solitary kidneys and reflux managed between 1981 and 1996 were reviewed. Solitary kidneys were documented by nuclear renography and ultrasonography; reflux was graded after cystography. Management consisted of observation and antimicrobial prophylaxis or surgery by ureteroneocystostomy or subureteric injection of polytetrafluoroethylene (STING). Follow-up ranged from 3 months to 14 years and included serial cystography, sonography, and serum creatinine measurement. RESULTS: Twenty-one patients with a median follow-up of 26 months were identified. Etiologies included contralateral renal agenesis (14 children), multicystic dysplastic kidney (5 children), or nonfunctioning ureteropelvic junction obstruction (2 children). Low-grade (I to II) reflux was identified in 6 children, and high grade (III to V) was identified in 15. Reflux resolved in 20 patients. Five children with low-grade reflux were managed without surgery and demonstrated reflux resolution after a mean of 20.5 months. Renal function deteriorated in only 1 child. Ureteroneocystostomy was performed in 13 children with grades III to V reflux, and STING was performed in 1 child with grade II reflux. Every surgical patient maintained stable renal function and was infection-free during a mean follow-up of 56 months. Management by observation in 2 children with grades IV to V reflux resulted in spontaneous resolution in one and stable grade IV in the other. CONCLUSIONS: Reflux into the solitary functioning kidney may be managed by the same strategies used to manage unilateral reflux in children with two normally functioning kidneys: low-grade reflux by observation/ chemoprophylaxis until spontaneous resolution occurs, and higher grades by surgery to protect renal function; however, chemoprophylaxis and serial imaging may be used until well-defined indications for surgery are satisfied. Renal function should be monitored diligently. 相似文献
127.
A Brufsky P Fontaine-Rothe K Berlane P Rieker M Jiroutek I Kaplan D Kaufman P Kantoff 《Canadian Metallurgical Quarterly》1997,49(6):913-920
OBJECTIVES: Androgen ablation with luteinizing hormone-releasing hormone (LHRH) agonists, orchiectomy, or oral estrogens has significant untoward sexual side effects. We evaluated a combination of finasteride and flutamide as potency-sparing androgen ablative therapy (AAT) for advanced adenocarcinoma of the prostate. In addition, we evaluated whether finasteride provided additional intraprostatic androgen blockade to flutamide. METHODS: Twenty men with advanced prostate cancer were given flutamide, 250 mg orally three times daily. Serum prostate-specific antigen (PSA) values were measured weekly. At a nadir PSA value, finasteride, 5 mg orally every day, was added. PSA values were then measured weekly until a second nadir PSA value was achieved. Sexual function was evaluated at baseline, at the second nadir PSA value, and every 3 months thereafter. Testosterone, dihydrotestosterone (DHT), and dehydroepiandrostenedione (DHEA) levels were measured at baseline and at the first and second nadir PSA values. RESULTS: The median follow-up period was 16.9 months. Therapy failed in 1 patient with Stage D2 disease at 12 months, but an additional response to subsequent LHRH agonist therapy was observed. One patient developed National Cancer Institute grade 3 diarrhea and was withdrawn from the study. Seven of 20 men developed mild gynecomastia, and 3 of 20 developed mild transient liver function test elevations. Mean PSA levels were 94.6 +/- 38.2 ng/mL at baseline and 7.8 +/- 2.7 and 4.7 +/- 2.2 ng/mL at the first and second PSA nadir values, respectively (P = 0.034). Mean percent decline in PSA value from baseline was 87.0 +/- 3.1% with flutamide alone and 94.0 +/- 1.9% with both flutamide and finasteride (P = 0.001). Eleven of 20 men were potent at baseline. At the second nadir PSA value, 9 (82%) of 11 were potent, whereas 2 (18%) of 11 were impotent. With longer follow-up (median 16.4 months), 6 (55%) of 11 men were potent, 2 (18%) of 11 were partially potent, and 3 (27%) of 11 were impotent. With flutamide alone, testosterone rose a mean of 77 +/- 14.7% of baseline (P = 0.0001), DHEA fell a mean of 32.4 +/- 4.6% (P = 0.0001), and DHT was unchanged. With the addition of finasteride, testosterone rose another 14 +/- 6% (P = 0.06, not significant), DHEA was unchanged, and DHT fell a mean of 34.8 +/- 4.7% (P = 0.0009). CONCLUSIONS: Finasteride and flutamide were safe and well tolerated as AAT for advanced prostate cancer. Finasteride provided additional intraprostatic androgen blockade to flutamide, as measured by additional PSA suppression. Sexual potency was preserved initially in most patients, although there was a reduction in potency and libido in some patients on longer follow-up. Further evaluation of this therapy is needed. 相似文献
128.
It is demonstrated that a nonlinear Schrödinger equation with certain nonlinearities allows for an existence of multistate single solitons (i.e., single solitons with the same carried power but different propagation parameters). In nonlinear optics, these solitons may exist either in the form of short bistable pulses, or bistable self-trapping (both two- and three-dimensional). 相似文献
129.
130.
Stephen Alstrup Cyril Gavoille Haim Kaplan Theis Rauhe 《Theory of Computing Systems》2004,37(3):441-456
Several papers describe linear time algorithms to preprocess a tree, in order to answer subsequent nearest common ancestor
queries in constant time. Here, we survey these algorithms and related results. Whereas previous algorithms produce a linear
space data structure, in this paper we address the problem of distributing the data structure into short labels associated
with the nodes. Localized data structures received much attention recently as they play an important role for distributed
applications such as routing. We conclude our survey with a new simple algorithm that labels in O(n) time all the nodes of
an n-node rooted tree such that from the labels of any two nodes alone one can compute in constant time the label of their
nearest common ancestor. The labels assigned by our algorithm are of size O(log n) bits. 相似文献