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141.
LC Rome DA Syme S Hollingworth SL Lindstedt SM Baylor 《Canadian Metallurgical Quarterly》1996,93(15):8095-8100
Vertebrate sound producing muscles often operate at frequencies exceeding 100 Hz, making them the fastest vertebrate muscles. Like other vertebrate muscle, these sonic muscles are "synchronous," necessitating that calcium be released and resequestered by the sarcoplasmic reticulum during each contraction cycle. Thus to operate at such high frequencies, vertebrate sonic muscles require extreme adaptations. We have found that to generate the "boatwhistle" mating call (approximately 200 Hz), the swimbladder muscle fibers of toadfish have evolved (i) a large and very fast calcium transient, (ii) a fast crossbridge detachment rate, and (iii) probably a fast kinetic off-rate of Ca2+ from troponin. The fibers of the shaker muscle of rattlesnakes have independently evolved similar traits, permitting tail rattling at approximately 90 Hz. 相似文献
142.
SM Riordan CJ McIver BM Walker VM Duncombe TD Bolin MC Thomas 《Canadian Metallurgical Quarterly》1996,91(9):1795-1803
OBJECTIVES: To i) document the sensitivity and specificity of a combined scintigraphic/lactulose breath hydrogen test for small intestinal bacterial overgrowth and ii) investigate the validity of currently accepted definitions of an abnormal lactulose breath hydrogen test based on "double peaks" in breath hydrogen concentrations. METHODS: Twenty-eight subjects were investigated with culture of proximal small intestinal aspirate and a 10-g lactulose breath hydrogen test combined with scintigraphy. Gastroduodenal pH, the presence or absence of gastric bacterial overgrowth, and the in vitro capability of overgrowth flora to ferment lactulose were determined. RESULTS: Sensitivity (16.7%) and specificity (70.0%) of the lactulose breath hydrogen test alone for small intestinal bacterial overgrowth were poor. Combination with scintigraphy resulted in 100% specificity, because double peaks in serial breath hydrogen concentrations may occur as a result of lactulose fermentation by cecal bacteria. Sensitivity increased to 38.9% with scintigraphy, because a single rise in breath hydrogen concentrations, commencing before the test meal reaches the cecum, may occur in this disorder. Sensitivity remained suboptimal irrespective of the definition of small intestinal bacterial overgrowth used, the nature of the overgrowth flora, favorable luminal pH, the presence of concurrent gastric bacterial overgrowth, or the in vitro ability of the overgrowth flora to ferment lactulose. CONCLUSIONS: Definitions of an abnormal lactulose breath hydrogen test based on the occurrence of double peaks in breath hydrogen concentrations are inappropriate. Not even the addition of scintigraphy renders this test a clinically useful alternative to culture of aspirate for diagnosing small intestinal bacterial overgrowth. 相似文献
143.
JD Reveille GS Alarcón SE Fowler SR Pillemer R Neuner DO Clegg IS Mikhail DE Trentham JC Leisen G Bluhm SM Cooper H Duncan M Tuttleman SP Heyse JT Sharp B Tilley 《Canadian Metallurgical Quarterly》1996,39(11):1802-1807
OBJECTIVE: To examine the effect of alleles encoding the "shared"/"rheumatoid" epitope on rheumatoid arthritis (RA) disease severity in patients who participated in the minocycline in RA (MIRA) trial. METHODS: Of 205 patients with a week-48 visit, blood was available for typing of HLA-DRB1 and HLA-DQB1 in 174 (85%) and successfully completed in 169 (82%). Baseline erosions were used to assess disease severity and new erosions at the last visit served as a proxy for progression. RESULTS: At baseline, there was no association between the presence of erosive disease or rheumatoid factor status and the dose of rheumatoid epitope (homozygous, heterozygous, none) or the specific alleles identified. At the final visit, a gradient was observed for the 3 allelic subgroups (and their gene doses) in the occurrence of new erosions among the Caucasian placebo-treated, but not the minocycline-treated, patients. A treatment group/HLA-DR4 epitope interaction was demonstrated in multivariate analyses. Approximately two-thirds of African-American patients did not have the rheumatoid epitope. CONCLUSION: HLA-DRB1 oligotyping may be useful in predicting the progression of disease in some Caucasian patients. Our study corroborates the infrequency of the epitope among African-American patients with RA. 相似文献
144.
A van Teunenbroek SM de Muinck Keizer-Schrama T Stijnen M Jansen BJ Otten HA Delemarre-van de Waal T Vulsma JM Wit CW Rouwé HM Reeser JJ Gosen C Rongen-Westerlaken SL Drop 《Canadian Metallurgical Quarterly》1996,81(11):4013-4021
To optimize the growth promoting effect of growth hormone (GH), 65 previously untreated girls with Turner syndrome (TS), chronological age (CA) 2-11 yr, were randomized into 3 dosage regimen groups: A, B, and C, with a daily recombinant-human GH dose during 4 study years of 4-4-4-4, 4-6-6-6, and 4-6-8-8 IU/m2 b.s. The first GH dosage increase in groups B and C resulted in a significantly higher mean height velocity (HV) compared with constant dose group A. During the third year, when the dose was raised again only in group C, mean HV was significantly higher in groups B and C than in group A, and in group C compared with group B. In year 4 only group C mean HV remained significantly higher than group A. The pattern of change in HSDSCA (Dutch-Swedish-Danish Turner references) was identical; however, in year 4 mean delta HSDSCA in group B also remained significantly higher than group A. After 4 yr GH treatment, the following was determined. 1) The mean delta HSDSCA was significantly higher for groups B and C compared with group A, but not significantly different between groups B and C. 2) Although significantly higher compared with estimated values for untreated Dutch girls with TS, bone maturation of the GH treated girls was not significantly different between groups. 3) It was positively related with the degree of bone age (BA) retardation at start of study and negatively with baseline CA. 4) Both the modified Index of Potential Height (mIPHRUS) and a recently developed Turner-specific final height (FH) prediction method (PTSRUS), based on regression coefficients for H, CA, and bone age, showed significant increases in mean FH prediction, without significant differences between groups. PTSRUS values were markedly higher than the mIPHRUS values. Dose dependency could be shown for the area under the curve (AUC) for GH, but delta HSDSCA was not linearly related with AUC. Baseline GH binding protein (BP) levels were in 84% of the cases within the normal age range; the decrease in mean levels after 6 months GH was not significant. Mean insulin-like growth factor I (IGF-I) and IGFBP-3 plasma levels increased significantly, without significant differences between groups. delta HSDSCA during GH was dependent on IGF-I plasma levels at baseline and during the study period, beta-0.002 and beta-0.0004. Thus, a stepwise GH-dosing approach reduced the "waning" effect of the growth response after 4 yr treatment without undue bone maturation. FH prediction was not significantly different between treatment groups. Irrespective of the GH dose used, initiation of GH treatment at a younger age was beneficial after 4 yr GH when expressed as actual cm gained or as gain in FH prediction, but was not statistically significant when expressed as delta HSDSCA over the study period. 相似文献
145.
Advances in multimedia data acquisition and storage technology have led to the growth of very large multimedia databases.
Analyzing this huge amount of multimedia data to discover useful knowledge is a challenging problem. This challenge has opened
the opportunity for research in Multimedia Data Mining (MDM). Multimedia data mining can be defined as the process of finding
interesting patterns from media data such as audio, video, image and text that are not ordinarily accessible by basic queries
and associated results. The motivation for doing MDM is to use the discovered patterns to improve decision making. MDM has
therefore attracted significant research efforts in developing methods and tools to organize, manage, search and perform domain
specific tasks for data from domains such as surveillance, meetings, broadcast news, sports, archives, movies, medical data,
as well as personal and online media collections. This paper presents a survey on the problems and solutions in Multimedia
Data Mining, approached from the following angles: feature extraction, transformation and representation techniques, data
mining techniques, and current multimedia data mining systems in various application domains. We discuss main aspects of feature
extraction, transformation and representation techniques. These aspects are: level of feature extraction, feature fusion,
features synchronization, feature correlation discovery and accurate representation of multimedia data. Comparison of MDM
techniques with state of the art video processing, audio processing and image processing techniques is also provided. Similarly,
we compare MDM techniques with the state of the art data mining techniques involving clustering, classification, sequence
pattern mining, association rule mining and visualization. We review current multimedia data mining systems in detail, grouping
them according to problem formulations and approaches. The review includes supervised and unsupervised discovery of events
and actions from one or more continuous sequences. We also do a detailed analysis to understand what has been achieved and
what are the remaining gaps where future research efforts could be focussed. We then conclude this survey with a look at open
research directions. 相似文献
146.
FRCT: fuzzy-rough classification trees 总被引:1,自引:1,他引:0
Using fuzzy-rough hybrids, we have proposed a measure to quantify the functional dependency of decision attribute(s) on condition
attribute(s) within fuzzy data. We have shown that the proposed measure of dependency degree is a generalization of the measure
proposed by Pawlak for crisp data. In this paper, this new measure of dependency degree has been encapsulated into the decision
tree generation mechanism to produce fuzzy-rough classification trees (FRCT); efficient, top-down, multi-class decision tree
structures geared to solving classification problems from feature-based learning examples. The developed FRCT generation algorithm
has been applied to 16 real-world benchmark datasets. It is experimentally compared with the five fuzzy decision tree generation
algorithms reported so far, and the rough decomposition tree algorithm. Comparison has been made in terms of number of rules,
average training time, and classification accuracy. Experimental results show that the proposed algorithm to generate FRCT
outperforms existing fuzzy decision tree generation techniques and rough decomposition tree induction algorithm.
Dr. Rajen Bhatt has obtained his B.E. and M.E. both in Control and Instrumentation, from S.S. Engineering College, Bhavnagar, and from Delhi College of Engineering, New Delhi in 1999 and 2002, respectively. He has obtained his Ph.D. from the Department of Electrical Engineering, Indian Institute of Technology Delhi, INDIA in 2006. He was actively engaged in the development of multimedia course on Control Engineering under the National Program on Technology Enabled Learning (NPTEL). He is a regular reviewer of International Journals like Pattern Recognition, Information Sciences, Pattern Analysis and Applications, and IEEE Trans. on Systems, Man and Cybernatics. Since June 2005, he is working with Imaging team of Samsung India Software Centre as a Lead Engineer. He also serves as a Member of Patent Review Committee at Samsung. He has published several research papers in reputed journals and conferences. His current research interests are Pattern Classification and Regression, Soft Computing, Data mining, Patents and Trademarks, and Information Technology for Education. He holds an expertise over industry standard software project management. Dr. M. Gopal has obtained his B.Tech. (Electrical), M.Tech. (Control systems), and Ph.D. (Control Systems) degrees. all from Birla Institute of Technology and Science, Pilani in 1968, 1970, and 1976, respectively. He has been in the teaching and research field for the last three and half decades; associated with NIT Jaipur, BITS Pilani, IIT Bombay, City University London, and University Technology Malaysia, and IIT Delhi. Since January 1986 he is a Professor with the Electrical Engineering Department, Indian Institute of Technology Delhi. He has published six books in the area of Control Engineering, and a video course on Control Engineering including complete presentation and student questionnaires. He has also published interactive web-compatible multimedia course on Control Engineering, under National Program on Technology Enabled Learning (NPTEL). He has published several research papers in referred journals and conferences. His current research interests include Machine learning, Soft computing technologies, Intelligent control, and e-Learning. 相似文献
Rajen B. BhattEmail: |
Dr. Rajen Bhatt has obtained his B.E. and M.E. both in Control and Instrumentation, from S.S. Engineering College, Bhavnagar, and from Delhi College of Engineering, New Delhi in 1999 and 2002, respectively. He has obtained his Ph.D. from the Department of Electrical Engineering, Indian Institute of Technology Delhi, INDIA in 2006. He was actively engaged in the development of multimedia course on Control Engineering under the National Program on Technology Enabled Learning (NPTEL). He is a regular reviewer of International Journals like Pattern Recognition, Information Sciences, Pattern Analysis and Applications, and IEEE Trans. on Systems, Man and Cybernatics. Since June 2005, he is working with Imaging team of Samsung India Software Centre as a Lead Engineer. He also serves as a Member of Patent Review Committee at Samsung. He has published several research papers in reputed journals and conferences. His current research interests are Pattern Classification and Regression, Soft Computing, Data mining, Patents and Trademarks, and Information Technology for Education. He holds an expertise over industry standard software project management. Dr. M. Gopal has obtained his B.Tech. (Electrical), M.Tech. (Control systems), and Ph.D. (Control Systems) degrees. all from Birla Institute of Technology and Science, Pilani in 1968, 1970, and 1976, respectively. He has been in the teaching and research field for the last three and half decades; associated with NIT Jaipur, BITS Pilani, IIT Bombay, City University London, and University Technology Malaysia, and IIT Delhi. Since January 1986 he is a Professor with the Electrical Engineering Department, Indian Institute of Technology Delhi. He has published six books in the area of Control Engineering, and a video course on Control Engineering including complete presentation and student questionnaires. He has also published interactive web-compatible multimedia course on Control Engineering, under National Program on Technology Enabled Learning (NPTEL). He has published several research papers in referred journals and conferences. His current research interests include Machine learning, Soft computing technologies, Intelligent control, and e-Learning. 相似文献
147.
Two bacteriophages were isolated from field collected samples representing two different mosquito breeding places. The phage AB-1 (isolated from Abheit village, Faiyoum Governorate "seepage water") and the phage GA-2 (isolated from El-Gabal El-Asfer Qualyobia Governorate "sewage drain water") were purified. Both bacteriophages were ultrastructurally described with respect to their morphology, dimensions, phases of bacterial attack and lysogeny. No major differences were observed between both isolated phages in relation to specificity, however; they were isolated from two different types of breeding places and two different geographic areas as well. This study may assume a wide host range of the isolated phages and reflect how bacterial insecticides used for mosquito larval control could be inhibited by such bacteriophage. 相似文献
148.
DA Danford BM McManus SM Nielsen MG Levine HW Needelman 《Canadian Metallurgical Quarterly》1993,14(4):242-246
Correlative echocardiographic and pathological findings in a thoracopagus with conjoined hearts are reported. One twin had tricuspid atresia with discordant atrioventricular connections and concordant ventriculoarterial connections. The morphologic right ventricle was hypoplastic and there was a large muscular ventricular septal defect. The other twin had hypoplasia of the mitral valve anulus and left ventricle with double-outlet right ventricle and pulmonary valve atresia. The tricuspid valve was severely insufficient in part because of a large orifice and redundant, elongated leaflets with abnormal chordal attachments. The left ventricles of these two twins shared a perforated common "free wall" with at least two large defects allowing mixing of the circulations at that level. Not all anatomic details were established conclusively by fetal echocardiography; however, sufficient diagnostic information was obtained to support a decision not to aggressively resuscitate these twins after elective cesarean delivery at 31 weeks' gestation. 相似文献
149.
Effect of alloying on the hydriding characteristics of FeTi with noble metals such as platinum and palladium (5% by weight) has been investigated. It is observed that palladium has a favourable effect with respect to easy activation, decreased hysteresis and lower plateau pressures for hydrogen absorption and desorption process. For Pd/FeTi, a saturation composition of Pd/FeTiH1.85 having the -phase, has been obtained. Unlike this, for Pt/FeTi, the total hydrogen absorption is decreased significantly and a saturation composition of Pt/FeTiH1.5 having only 2 phase, is observed. 相似文献
150.
The effects of 27 mM K+ and of 6.7 mM theophylline on the release of growth hormone (GH) by rat hemipituitaries in vitro were investigated using bioassay (rat tibia test) and radioimmunoassay (RIA). Both agents markedly increased the release of immunoreactive GH. High K+ also promoted the release of bioactive GH but to a much lesser degree than RIA-GH. Theophylline did not consistently affect the release of bioassay-detectable GH. The results suggest that these agents promote massive release of a form of immunoreactive GH (possibly "immature") that has little or no activity in the bioassay. Theophylline is relatively more effective in this regard than is elevated K+. 相似文献