The enzyme, bromelain, is known to catalyze protein proteolysis and to activate many protective processes occurring with participation of the nervous, immune, and endocrine systems. In this connection, a computer anal...
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The enzyme, bromelain, is known to catalyze protein proteolysis and to activate many protective processes occurring with participation of the nervous, immune, and endocrine systems. In this connection, a computer analysis of all the possible 4-6-member fragments of bromelain was performed by means of a comparison of their primary structures with amino acid sequences of all the known natural oligopeptides. Information from the EROP-Moscow data base that contains data on the structures and functions of natural oligopeptides and specially written computer programs were used for this purpose. It was shown that tetra-, penta-, and hexapeptide fragments of the bromelain molecules are involved in amino acid sequences of many natural oligopeptides, including antimicrobial oligopeptides, toxins, neuropeptides, and hormones. These results confirmed deep relationship between the basic regulatory systems. In connection with the obtained data, the process of oligopeptide biogenesis, the possibility of natural formation of regulatory oligopeptides from the bromelain molecules, and correspondence of the obtained results with the conception of oligopeptide continuum are discussed. A possible practical importance of active fragments of protein enzymes in regulatory processes of a living organism is noted.
In this article, systematic performance evaluation of a continuous-scale sleep depth measure will be discussed. Our main objective has been to select the adjustable analysis parameters such that the best possible corr...
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In this article, systematic performance evaluation of a continuous-scale sleep depth measure will be discussed. Our main objective has been to select the adjustable analysis parameters such that the best possible correspondence between method output and standard visual sleep staging could be achieved. Sleep depth estimation was based on continuous monitoring of short-time EEG synchronization through the local mean frequency of the EEG. During the experiments, total amount of 752 different combinations of four adjustable parameters were compared based on all-night sleep EEG recordings of 15 healthy subjects. Optimization strategy applied was based on maximizing the weighted average of pair-wise separabilities of EEG mean frequency distributions in all the standard sleep stage pairs. Finally, robustness of the optimized parameters was verified with an independent dataset of 34 all-night sleep recordings. Our results show that clear topological differences between brain hemispheres and different electrode locations exist. Performance improvements of even 20-30% units can be achieved by proper selection of analysis parameters and the EEG derivation used for the analysis. Remarkable independence of system performance on the analysis window length leads to improved temporal resolution compared to that achieved through standard visual analysis. In addition to giving practical suggestions on the parameter selection, we also propose a possible method for improving stage separability especially between S2 and REM. (C) 2006 IPEM. Published by Elsevier Ltd. All rights reserved.
In this paper a method is presented for the determination of the differences between the worm gear tooth surface processed by an oversized hob of finite number of teeth or by a flying tool, and the theoretically requi...
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In this paper a method is presented for the determination of the differences between the worm gear tooth surface processed by an oversized hob of finite number of teeth or by a flying tool, and the theoretically required gear tooth surface. The influence of hob oversize and machine tool settings on tooth contact pressure and transmission errors is determined. The full geometry and kinematics of gear tooth processing by an oversized hob or by a flying tool is included. The theoretical background is implemented by a computer program. By using this program, the influence of relevant design parameters of the worm gear set and the hob and of machine tool settings on processed gear tooth errors and on loaded tooth contact of the worm gear pair is investigated and discussed.
In this paper we investigate the capabilities of the discrete dipole approximation (DDA) to simulate scattering from particles that are much larger than the wavelength of the incident light, and describe an optimized ...
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In this paper we investigate the capabilities of the discrete dipole approximation (DDA) to simulate scattering from particles that are much larger than the wavelength of the incident light, and describe an optimized publicly available DDA computer program that processes the large number of dipoles required for such simulations. Numerical simulations of light scattering by spheres with size parameters x up to 160 and 40 for refractive index m = 1.05 and 2, respectively, are presented and compared with exact results of the Mie theory. Errors of both integral and angle-resolved scattering quantities generally increase with m and show no systematic dependence on x. Computational times increase steeply with both x and m, reaching values of more than 2 weeks on a cluster of 64 processors. The main distinctive feature of the computer program is the ability to parallelize a single DDA simulation over a cluster of computers, which allows it to simulate light scattering by very large particles, like the ones that are considered in this paper. Current limitations and possible ways for improvement are discussed. (c) 2007 Elsevier Ltd. All rights reserved.
Productivity in Nigeria is decreasing: this has adversely affected the average standard-of-living of the population and led to economic hardship. HIV/AIDS, hunger, disease and wars have lowered African productivity an...
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Productivity in Nigeria is decreasing: this has adversely affected the average standard-of-living of the population and led to economic hardship. HIV/AIDS, hunger, disease and wars have lowered African productivity and the effectivenesses of public utilities have declined, while unemployment and crime are on the increase. A computer program, which considers the combined concept of partial productivity, total productivity measurement and reliability in order to analyse the effectiveness of a firm, society or nation has been developed. Its predictions have been tested with data from a Nigerian petroleum-product marketing company, namely Rock Oil and Gas Ltd., Aba, Abia State: the management of this business is representative of those of many Nigerian firms. The developed software (see Appendix) can help in identifying the causes of productivity problems, which can so adversely affect the performance of any organisation. (c) 2007 Elsevier Ltd. All rights reserved.
A simplified method has been developed for designing and calculating sprinkling systems by cutting lines across laterals at points next to the first sprinkler with a view to divide the system into two separate parts;f...
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A simplified method has been developed for designing and calculating sprinkling systems by cutting lines across laterals at points next to the first sprinkler with a view to divide the system into two separate parts;field and basic. Equations of lateral pressure heads were used to express the relationship between inlet pressure head and velocity of the flow pumped to laterals on the field part. The above equations were then used to set up calculating conditions for the Basic part by unsteady flow method in order to define head and discharge at downstream end of the pipe in the Basic part. The forward step method was used for determining distributions of the pressure head and the emitter discharge along each lateral. A calculating schema on computer has been carried out in order to apply the method to any sprinkling system. The procedure of analysis and calculation showed that this method is generally accurate, simple and rapid.
A closing wedge osteotomy of the lumbar spine may be considered to correct posture and spinal balance in progressive thoracolumbar kyphotic deformity caused by ankylosing spondylitis (AS). Adequate deformity planning ...
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A closing wedge osteotomy of the lumbar spine may be considered to correct posture and spinal balance in progressive thoracolumbar kyphotic deformity caused by ankylosing spondylitis (AS). Adequate deformity planning is essential for reliable prediction of the effect of surgical correction of the spine on the sagittal balance and horizontal gaze of the patient. The effect of a spinal osteotomy on the horizontal gaze is equal to the osteotomy angle. However, the effect of a spinal osteotomy on the sagittal balance depends on both the correction angle and the level of osteotomy simultaneously. The relation between the correction angle, the level of osteotomy and the sagittal balance of the spine can be expressed by a mathematical equation. However, this mathematical equation is not easily used in daily practice. We present the computer program ASKyphoplan that analyses and visualizes the planning procedure for sagittal plane corrective osteotomies of the spine in AS. The relationship between the planned correction angle, level of osteotomy and sagittal balance are coupled into the program. The steps taken during an ASKyphoplan run are outlined, and the clinical application is discussed. The application of the program is illustrated by the analysis of the data from a patient recently treated by a lumbar osteotomy in AS. The software can be used free of charge on the internet at http://*** under the heading "research" in the menu.
Structural transformations taking place during annealing of rapidly-quenched soft magnetic ribbons from the Finemet type and Hitperm type alloys were investigated. The X-ray quantitative phase analysis and X-ray diffu...
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ISBN:
(纸本)390845140X
Structural transformations taking place during annealing of rapidly-quenched soft magnetic ribbons from the Finemet type and Hitperm type alloys were investigated. The X-ray quantitative phase analysis and X-ray diffusion scattering methods were used. It was found that the structural changes in the alloys studied, including crystallisation process and short-range ordering in the amorphous phase, are reflected by the changes in their magnetic properties. These properties, and particularly the magnitude of saturation induction B-s, depend on the content of cobalt and silicon in these alloys and on short-range order in the amorphous phase.
Aim To evaluate the usability and reliability of three different visual acuity (VA) testing procedures using Landolt C's in 8 positions with a semi-automated computer program in school children. Methods 100 school...
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Aim To evaluate the usability and reliability of three different visual acuity (VA) testing procedures using Landolt C's in 8 positions with a semi-automated computer program in school children. Methods 100 school children (median 7 years, 59 boys and 41 girls) were included;only the better eye was tested. We used the semi-automated computer program CORVIS (R). VT in a forced choice method. Three different test strategies were employed, each two times: A) DIN, B) Standard-Staircase and C) Best-PEST procedure with sequences A, B, C or A, C, B. Results Average testing time was 100s +/- 45 (DIN), 59s +/- 36 (Staircase) and 77s +/- 25 (Best-PEST). The mean VA estimated with DIN was equivalent to that with the Best-PEST procedure. However, the mean VA with Standard-Staircase was one line less. In DIN, 76% of the retest scores were within 0.1 logMAR unit of the initial test score (Staircase: 72%, Best-PEST 73%). The 95% confidence interval of test-retest reliability was calculated to be -0.05 +/- 0.24 logMAR in DIN, +0.02 +/- 0.32 logMAR in Staircase, and 0.00 +/- 0.29 logMAR in Best-PEST. Conclusion A high percentage of children aged 6 to 9 years (98%) can be tested with Landolt C's (8 positions). We found a decreasing test-retest reliability starting from DIN via Best-PEST to Staircase in this configuration.
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