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1.
2.
The reactions of immunoglobulins with protein A and, subsequently, of antibodies to these immunoglobulins were continuously monitored by a piezoelectric biosensor. AT-cut crystals, with a fundamental resonant frequency of 10 MHz, were mounted in a Plexiglas holder, and one side was directly coated with protein A. Upon exposure to solutions containing rabbit or human IgG the resonant frequency was followed continuously and its decrease due to the binding of IgG to protein A observed. Subsequent addition of sheep antihuman IgG to the now immobilized human IgG caused a specific 3-fold further decrease in resonant frequency. We observed a frequency change of approximately 1 Hz fore each 10 ng of added immunoglobulin. Decreasing the pH to 3 released the bound IgG but not the protein A and permitted reuse of the crystal for further IgG binding. 相似文献
3.
Observational methods were used to examine aggressive children's peer relations in 2 contexts: when being teased by a peer and when interacting with a best friend. Because aggressive children may have more difficulty than nonaggressive children in both peer contexts, the authors also examined whether relations between behaviors across contexts varied as a function of aggression. Results indicated that aggression was related to children's behavior when provoked. Children's behavior when provoked was associated with fewer positive and more negative interactions with their best friend, particularly for aggressive children. Results are discussed with respect to social norms in middle childhood and informing interventions for aggressive children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
G. A. Gagnon K. C. O’Leary C. J. Volk C. Chauret L. Stover R. C. Andrews 《Canadian Metallurgical Quarterly》2004,130(11):1269-1279
Drinking water utilities may be required to change disinfectant to improve water quality and meet more stringent disinfection regulations. This research was conducted to assess and compares chlorine dioxide to free chlorine and chloramines on bacterial water quality monitored within model distribution systems (i.e., annular reactors). Following colonization with nondisinfected water, annular reactors containing either polycarbonate or cast iron coupons were treated with free chlorine, chlorine dioxide or chloramines. Two disinfectant doses (low/high) were tested for each disinfectant. Under specific environmental conditions, bacterial inactivation varied as a function of the disinfectant type and dose, sample type (bulk water versus biofilm bacteria) and coupon material. The ranking by efficiency was as follows: chlorine dioxide > chlorine > chloramines. On preformed biofilms of 106–107?cfu/cm2, the continuous application of a disinfectant led to a log removal of heterotrophic bacteria concentrations for suspended and biofilm bacteria ranging from 1.1 to 4.0, and from 0.2 to 2.5, respectively. Doubling the amount of disinfectant doses led to an additional log inactivation of 1–2.5 of heterotrophic bacteria levels. This study demonstrates that bacterial inactivation in distribution systems is governed by various inter-related parameters. The data indicate that chlorine dioxide represents a viable alternative for secondary disinfection in distribution systems. 相似文献
5.
Katie L. J. Cederberg Umaer Hanif Vicente Peris Sempere Julien Hdou Eileen B. Leary Logan D. Schneider Ling Lin Jing Zhang Anne M. Morse Adam Blackman Paula K. Schweitzer Suresh Kotagal Richard Bogan Clete A. Kushida Yo-El S. Ju Nayia Petousi Chris D. Turnbull Emmanuel Mignot The STAGES Cohort Investigator Group 《International journal of molecular sciences》2022,23(14)
Obstructive sleep apnea (OSA), a disease associated with excessive sleepiness and increased cardiovascular risk, affects an estimated 1 billion people worldwide. The present study examined proteomic biomarkers indicative of presence, severity, and treatment response in OSA. Participants (n = 1391) of the Stanford Technology Analytics and Genomics in Sleep study had blood collected and completed an overnight polysomnography for scoring the apnea–hypopnea index (AHI). A highly multiplexed aptamer-based array (SomaScan) was used to quantify 5000 proteins in all plasma samples. Two separate intervention-based cohorts with sleep apnea (n = 41) provided samples pre- and post-continuous/positive airway pressure (CPAP/PAP). Multivariate analyses identified 84 proteins (47 positively, 37 negatively) associated with AHI after correction for multiple testing. Of the top 15 features from a machine learning classifier for AHI ≥ 15 vs. AHI < 15 (Area Under the Curve (AUC) = 0.74), 8 were significant markers of both AHI and OSA from multivariate analyses. Exploration of pre- and post-intervention analysis identified 5 of the 84 proteins to be significantly decreased following CPAP/PAP treatment, with pathways involving endothelial function, blood coagulation, and inflammatory response. The present study identified PAI-1, tPA, and sE-Selectin as key biomarkers and suggests that endothelial dysfunction and increased coagulopathy are important consequences of OSA, which may explain the association with cardiovascular disease and stroke. 相似文献
6.
Julianne Chung Matthias Chung Dianne P. O’Leary 《Journal of Mathematical Imaging and Vision》2012,44(3):366-374
Data acquisition errors due to dead pixels or other hardware defects can cause undesirable artifacts in imaging applications. Compensating for these defects typically requires knowledge such as a defective pixel map, which can be difficult or costly to obtain and which is not necessarily static. However, recent calibration data is readily available in many applications. In this paper, we compute optimal filters for image deconvolution with denoising using only this calibration data, by minimizing the empirical Bayes risk. We derive a bound on how the reconstruction changes as the number of dead pixels grows. We show that our approach is able to reconstruct missing information better than standard filtering approaches and is robust even in the presence of a large number of defects and to defects that arise after calibration. 相似文献
7.
P. Messina E. Felten P. Hipes R. Williams A. Alagar A. Kamrath R. Leary W. Pfeiffer J. Rogers D. Walker 《Concurrency and Computation》1990,2(3):195-255
Recently, a number of advanced architecture machines have become commercially available. These new machines promise better cost performance than traditional computers, and some of them have the potential of competing with current supercomputers, such as the CRAY X-MP, in terms of maximum performance. This paper describes the methodology and results of a pilot study of the performance of a broad range of advanced architecture computers using a number of complete scientific application programs. The computers evaluated include:
- 1 shared-memory bus architecture machines such as the Alliant FX/8, the Encore Multimax, and the Sequent Balance and Symmetry
- 2 shared-memory network-connected machines such as the Butterfly
- 3 distributed-memory machines such as the NCUBE, Intel and Jet Propulsion Laboratory (JPL)/Caltech hypercubes
- 4 very long instruction word machines such as the Cydrome Cydra-5
- 5 SIMD machines such as the Connection Machine
- 6 ‘traditional’ supercomputers such as the CRAY X-MP, CRAY-2 and SCS-40.
8.
Next generation backbone networks will likely consist of IP routers as well as optical cross connects (OXCs) and will deploy an optical control plane protocol. Generalized Multi Protocol Label Switching (GMPLS) has been proposed as the candidate of choice for the control plane. Optical fibers may carry large volumes of traffic and therefore adequate mechanisms must exist to enable the network to automatically recover from failures of fiber. In mission critical networks survivability becomes very important. We investigate the problem of autonomous recovery in such networks. The literature contains work in this area that investigates the problem of multilayer recovery. Such recovery had only been sequential in the sense that the published work recovers first in the optical domain, assuming the availability of redundant resources, and then proceeds to recover packet label switched paths. We report a recovery procedure for recovering packet label switch paths (packet LSPs) and lambda label switch paths (λLSP) concurrently. We have conducted an OPNET-based simulation study that compares the performance of the concurrent scheme with the previously published sequential two-layer recovery scheme. The study shows that the concurrent two-layer recovery scheme performs as much as forty-four percent faster than the sequential two-layer recovery scheme. 相似文献
9.
Leary SP Pilgrim SM 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1999,46(5):1155-1163
Energy conversion efficiency is a critical parameter for all electromechanical materials. Although excellent techniques are available for linear materials, nonlinearities complicate the determination of conversion efficiency in electrostrictive Pb(Mg(1/3)Nb(2/3 ))O(3) (PMN). The field dependence of the elastic modulus presents additional problems. A technique combining pulse-echo ultrasound has been developed to approximate the change in the Young's modulus with applied field. A 30% decrease was observed at 1 MV/m (from ~100 to ~70 GPa). The boundary condition for these measurements was a constant electric field as opposed to constant dielectric displacement. In combination with the results from harmonic analysis, the modulus data may be used to determine the electromechanical conversion efficiency. This has been accomplished using an energy balance criterion for a PMN-based composition (with and without dc bias). The resulting longitudinal coupling values are >0.5 for practical electric fields (<1 MV/m peak). 相似文献
10.
Semiconductor photocatalysis has important applications such as achieving sustainable energy generation and treating environmental pollution. TiO2 has been the most widely-researched photocatalyst, but suffers from low efficiency and narrow light response range. Combining TiO2 with carbonaceous nanomaterials is being increasingly investigated as a means to increase photocatalytic activity, and demonstrations of enhancement are plentiful. This review surveys the literature and highlights recent progress in the development of nanocarbon-TiO2 photocatalysts, covering activated carbon, carbon doping, carbon nanotubes, [60]-fullerenes, graphene, thin layer carbon coating, nanometric carbon black and more recently developed morphologies. Mechanisms of enhancement, synthesis routes and future applications are summarised and discussed. New insight and enhanced photocatalytic activity may be provided by novel nanocarbon-TiO2 systems. Ongoing challenges and possible new directions are outlined. 相似文献