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31.
Hopkins William D.; Bennett Allyson J.; Bales Stacy L.; Lee Jennifer; Ward Jeannette P. 《Canadian Metallurgical Quarterly》1993,107(4):403
Behavioral laterality was studied in a captive group of 11 bonobos (Pan paniscus). In an observational method a significant left lateral bias in carrying and a right lateral bias in leading limb were found. Direction of lateral bias in carrying and leading limb was enhanced when Ss maintained a bipedal posture. Analysis of bimanual feeding behavior revealed a significant right-hand bias for eating when the Ss were holding food with their left hand. In an experimental method a significant shift toward greater right-hand use was found when Ss were required to maintain a bipedal, rather than a quadrupedal, posture. There was no evidence of lateral bias for measures of face touching, self-touching, or gestures. The results are discussed in the context of previous reports of primate laterality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
A card survey was sent to 340 veterinarians in the Urban, Delta, Highland and Coastal Plain regions of Arkansas. Veterinarians were asked to indicate numbers of dogs tested, confirmed Dirofilaria immitis positive, diagnostic techniques, frequency and period tested. A significantly greater percentage of dogs tested D. immitis positive in the Delta region as compared with the Urban region. There were no significant differences in the percentage of treated dogs on prophylaxis or the types of diagnostic tests among regions. 相似文献
33.
T Roldán-Arjona FL Luque-Romero RR Ariza J Jurado C Pueyo 《Canadian Metallurgical Quarterly》1994,9(4):200-209
We investigated the influence of the alkyltransferases (ATases) encoded by the ada and ogt genes of Escherichia coli on the mutational specificity of alkylating agents. A new mutational assay for selection of supF- mutations in shuttle-vector plasmids was used. Treating plasmid-bearing bacteria with N-methyl-N-nitrosourea (MNU), N-ethyl-N-nitrosourea (ENU), and ethyl methanesulfonate (EMS) dramatically increased the mutation frequency (from 33-fold to 789-fold). The vast majority of mutations (89-100%) were G:C-->A:T transitions. This type of mutation increased in ada- (MNU) or ogt- (ENU) bacteria, suggesting that repair of O6-methylguanine by ada ATase and repair of O6-ethylguanine by ogt ATase contribute mainly to the decrease in G:C-->A:T transitions. The analysis of neighboring base sequences revealed an overabundance of G:C-->A:T transitions at 5'-GG sequences. The 5'-PuG bias increased in ATase-defective cells, suggesting that these sequences were not refractory to repair. G:C-->A:T transitions occurred preferentially in the untranscribed strand after in vivo exposure. That this strand specificity was detected even in bacteria devoid of ATase activity (ada- ogt-) and not after in vitro mutagenesis suggests a bias for damage induction rather than for DNA repair. Highly significant differences were found between the in vivo and in vitro incidences of G:C-->A:T substitutions at the two major hotspots, positions 123 (5'-GGG-3'; antisense strand) and 168 (5'-GGA-3'; sense strand). These results are explained by differences in the probability of formation of stem-loop structures in vivo and in vitro. 相似文献
34.
35.
Les Hatton Andy Wright Stuart Smith Gregg Parkes Paddy Bennett Robert Laws 《Software》1988,18(4):301-329
The portability of software has become a major commercial issue in recent times. Such portability does not come easily, as few if any computer languages are really portable in practice. An additional complicating factor, especially in the commercial environment, is that the resulting software must be efficient. This paper describes the design and successful implementation of a 500,000+ line portable FORTRAN 77 package for the processing of seismic data. The package exhibits demonstrably high efficiency on a wide variety of machines from minicomputers to the largest supercomputers. Experiences gained during this exercise throw much light on the integration of the various thought processes which occur during the software engineering cycle, especially the notion of locality. 相似文献
36.
Lowe Rob; Bennett Paul; Walker Ian; Milne Sarah; Bozionelos George 《Canadian Metallurgical Quarterly》2003,22(5):464
The theory of planned behavior suggests attitudes are a product of salient beliefs. This study examined whether aggregating salient beliefs was plausible within a more biologically centered information-processing environment. A neural network was used to examine associations among beliefs relating to exercise intention. Data on intentions and behavioral, normative, and control beliefs from 114 respondents were used to train (by error backpropagation) a neural network to associate beliefs with intention. The R2 between the network's estimated and self-reported intention was .66. The network's representation comprised 6 belief profiles associated with high, moderate, or low behavioral intention. The neural network accommodated complex relationships among beliefs and belief-intention associations and indicated how high-level constructs such as attitudes may be viewed as the best fit (compromise state) between aroused beliefs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
F Thonney FL Munier A Balmer G Pescia DF Schorderet 《Canadian Metallurgical Quarterly》1996,85(35):1058-1062
Retinoblastoma, a tumor of the immature retina concerns babies and young infants in particular. They make up for 14% of malignomas in the first years of life. There are two types of retinoblastoma: In the first two alleles of the gene Rb1 must be inactivated sequentially in the same retinoblast cell until this may escape control. In this case the retinoblastoma is always unilateral and unifocal. This is explained by the lower frequency of two mutations in one retinoblast. The other type, however, is inherited: One allele Rb1 is inactivated in all cells of the organism by mutation. The probability that a second mutation arrives in different retinoblasts is thus high. In this case bilateral multifocal tumors develop. Characterization of the Rb1 gene has permitted identification or at least determination of a haplotype in persons at risk. This knowledge is decisive for early recognition of babies at risk and for genetic counselling. 相似文献
38.
PR Bennett R Warwick J Vaughan H Chana A Lubenko NM Fisk 《Canadian Metallurgical Quarterly》1994,101(3):246-249
OBJECTIVE: To assess the effectiveness of a newly developed individualised birthweight ratio (IBR), which corrects for physiological birthweight determinants, in identifying infants at risk from the complications of macrosomia. DESIGN: Prospective observational study. SETTING: Obstetric unit, Nottingham City Hospital. SUBJECTS: 2835 women delivered between December 1991 and July 1992 and the infants of 624 of these, selected by virtue of their birthweight for gestation and IBR centile positions. MAIN OUTCOME MEASURES: Skinfold thickness and ponderal index measurements, operative delivery, shoulder dystocia, fetal trauma, impaired glucose tolerance. RESULTS: Using an IBR above the 90th centile as a cut off results in 2.4% of infants being reclassified as normally grown and 3.1% are reclassified as large. The IBR does not result in the identification of any more infants with abnormal ponderal indices or skinfold thicknesses than birthweight for gestation. It does, however, identify more of the infants at risk of operative delivery, shoulder dystocia, fetal trauma and impaired glucose tolerance. CONCLUSION: The IBR significantly improves upon birthweight for gestation in identifying infants who suffer from the complications of relative macrosomia. 相似文献
39.
S Dawson D Bennett SD Carter M Bennett J Meanger PC Turner MJ Carter I Milton RM Gaskell 《Canadian Metallurgical Quarterly》1994,56(2):133-143
Twelve specific pathogen-free cats were infected either by intra-articular inoculation or by contact exposure to one of two strains of feline calicivirus (FCV), either F65, a field strain originating from an outbreak of lameness in a group of cats, or a vaccine strain. Following either route of exposure, both strains induced signs typical of FCV infection including oral and nasal ulceration, conjunctivitis and ocular discharge. These signs were of equal severity for both virus strains, but overall, following either route of infection, F65 induced more severe disease than the vaccine strain, with marked pyrexia, lethargy and lameness. Vaccine virus only induced a relatively mild lameness following intra-articular inoculation. Gross pathological and histopathological lesions were seen in some of the joints, but again changes were more severe in the F65-exposed cats. Virus was isolated from both normal and affected joints from both groups of F65-exposed cats, and from a joint from each cat inoculated intra-articularly with vaccine virus. Mild transient lameness was also seen in one of two control cats inoculated intra-articularly, but no pathological changes were seen or virus isolated from joints. A cDNA probe used in RNA dot blot hybridisation experiments was found to be specific and more sensitive than virus isolation in detecting FCV in selected tissues. This may be useful in future studies on the pathogenesis of FCV disease and in studies on viral persistence in FCV carriers. 相似文献
40.
Joseph Dunn Michael Neufeld Anmol Sheth Dirk Grunwald John Bennett 《Mobile Networks and Applications》2006,11(1):37-45
Many companies, organizations and communities are providing wireless hotspots that provide networking access using 802.11b wireless networks. Since wireless networks are more sensitive to variations
in bandwidth and environmental interference than wired networks, most networks support a number of transmission rates that
have different error and bandwidth properties. Access points can communicate with multiple clients running at different rates,
but this leads to unfair bandwidth allocation. If an access point communicates with a mix of clients using both 1 Mb/s and
11 Mb/s transmission rates, the faster clients are effectively throttled to 1 Mb/s as well. This happens because the 802.11
MAC protocol approximate “station fairness”, with each station given an equal chance to access the media. We provide a solution
to provide “rate proportional fairness”, where the 11 Mb/s stations receive more bandwidth than the 1 Mb/s stations. Unlike
previous solutions to this problem, our mechanism is easy to implement, works with common operating systems and requires no
change to the MAC protocol or the stations.
Joseph Dunn received an M.S. in computer science from the University of Colorado at Boulder in 2003, and B. S. in coputer science and
mathematics from the University of Arizona in 2001. His research interests are in the general area of computer systems, primarily
focusing on security and scalability in distributed systems. He is currently working on his Ph.D. in computer science from
the University of Colorado at Boulder.
Michael Neufeld received a Ph.D. in Computer Science from the University of Colorado at Boulder in December of 2004, having previously received
an M.S. in Computer Science from the University of Colorado at Boulder in 2000 and an A.B. in Computer Science from Princeton
University in 1993. His research interests are in the general area of computer system, specifically concentrating on wireless
networking, software defind/cognitive radio, and streerable antennas. He is currently a postdoc in the Computer Science department
at the University of Calorado at Boulder pursuing research related to software defined radio and new MAC protocols for steerable
phase array antennas.
Anmol Sheth is a Ph.D. student in Computer Science at the University of Colorado at Boulder. He received his B.S. in Computer Science
from the University of Pune, India in 2001. He has been co-leading the development of the MANTIS operating system. He has
co-authored three papers include MAC layer protocol design, energy-efficient wireless communication, and adapting communications
to mobility.
Dirk Grunwald received his Ph.D. from the University of Illinois in 1989 and joined the University of Colorado the same year. His work
addresses research and teaching in the broad area of “computer systems”, which includes computer architecture, operating systems,
networks, and storage systems. His interests also include issues in pervasive computing, novel computing models, and enjoying
the mountains. He is currently an Associate Professor in the Department of Computer Science and in Electrical and Computer
Engineering and is also the Director of the Colorado Center for Information Storage.
John Bennett is a Professor of Computer Science with a joint appointment in Electrical and Computer Engineering at the University of Colorado
at Boulder. He also serves as Associate Dean for Education in the College of Engineering and Applied Science. He joined the
CU-Boulder faculty in 2000, after serving on the faculty of Rice University for 11 years. While at Rice, Bennett pioneered
a course in engineering design for both engineering and non-engineering students that has been emulated at several universities
and high schools. In addition to other teaching awards, Bennett received the Keck Foundation National Award for Engineering
Teaching Excellence for his work on this course. Bennett received his Ph.D. in 1988 from the University of Washington. Prior
to completing his doctoral studies, he was a U.S. Naval Officer for several years and founded and served as President of Pacific
Mountain Research, Inc., where he supervised the design and development of a number of commercial computing systems. Bennett's
primary research interests are broadly focused in the area of distributed systems, and more narrowly in distributed information
management and distributed robotic macrosensors. 相似文献