9,788 research outputs found
The binding of glycosaminoglycans to peptides : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Biochemistry at Massey University
The overall aim this study was to examine the possibility of using immobilised polypeptide chains to fractionate/separate Glycosaminoglycans (GAG's) from mixtures. Initially individual samples of three GAG classes (chondroitin sulphate, dermatan sulphate and heparin) were characterised to establish purity and provide basic information. Once these samples had been characterised the samples were treated as standards. Three short poly-l-lysine (PLL) chains with defined length and orientation were synthesized. As a control a PLL chain with 633 residues was immobilised. The interaction of the GAG standards with these resins did not replicate published solution binding behaviour of longer PLL chains. This suggested a different mode of binding. The interaction of two lengths of PLL (126 and 633 residues) and the K8G peptide with the GAG standards in solution was investigated. These studies demonstrated that the mode of binding of GAG's to short PLL chains was radically different to the earlier reported solution binding studies. ÎČ-Strand dominates with the short PLL chains instead of α-helix established in the published solution binding studies. The interaction of two peptides PCI (264-283) and thrombospondin peptide with the GAG standards was studied using circular dichroism spectroscopy. In the case of the PCI peptide, each GAG induced different secondary structures. Chondroitin sulphate and heparin induced an α-helix, whereas dermatan sulphate gave ÎČ-strands. Heparin and dermatan sulphate induced double the amount of secondary structure compared to chondroitin sulphate. The strength of the interaction of GAG's with the peptide was also measured by the concentration of salt required to dissociate 50% of the complex. The figures for dermatan sulphate and heparin were found to be 0.1 and 0.3 M salt respectively. The binding of the GAG standards to the thrombospondin peptide did not elicit any detectable change in conformation of the peptide. Critical examination of published material on the interaction of GAG's (principally heparin) with short peptides, prompted the writer to propose two new complementary models. The first model examines binding in terms of the conformation of the peptide induced by binding to the GAG. It is composed of three components, the periodicity of polar and nonpolar residues within the peptide sequence, the spacing of pairs of basic residues and the spacing of pairs of acidic and basic residues. This model is successfully able to rationalise the binding behaviour of a number of GAG/peptide interactions in terms of the dominant secondary structure and the biological activity. The model is able to make a number of specific predictions. The second model examines the strength of the interaction between heparin and peptides containing the proposed consensus sequences for GAG binding sites. A significant correlation between the binding strength and an attribute derived from the sequence of the peptide was found using only one assumption. The assumption was that the peptides in the correlation bound to heparin with significant levels of ÎČ-strand. For the first time it is possible to rationalise the behaviour of GAG/peptide interactions in a coherent manner. The design of peptides that are capable of binding to specific GAG's now seems possible
Incorporating financial literacy into the secondary school accounting curriculum: a New Zealand perspective
This paper examines whether selected stakeholder groups believe accounting should continue to be taught as an elective subject in its current form at New Zealand secondary schools or whether incorporating a financial literacy component would increase the subjectâs relevance to students. A mixed method approach combining qualitative and quantitative research methods was used. An electronically administered survey was used to obtain the responses of secondary school accounting teachers, while additional insight in the form of semi-structured interviews was obtained from other stakeholders.
Although respondents generally agreed that students benefited from accounting as an elective subject at secondary school, all agreed that the development of financial literacy skills was important. Difficulties in introducing a new core subject into an already overcrowded curriculum were acknowledged. However, this difficulty could be overcome by making modifications to the subject âAccountingâ. As the most widespread, existing âfinanceâ related subject, Accounting would be the most appropriate vehicle through which to teach financial literacy
The dose-response relationship between training load and aerobic fitness in academy rugby union players
© 2018 Human Kinetics, Inc. Purpose: To identify the dose-response relationship between measures of training load (TL) and changes in aerobic fitness in academy rugby union players. Method: Training data from 10 academy rugby union players were collected during a 6-wk in-season period. Participants completed a lactate-threshold test that was used to assess VO 2 max, velocity at VO 2 max, velocity at 2 mmol/L (lactate threshold), and velocity at 4 mmol/L (onset of lactate accumulation; vOBLA) as measures of aerobic fitness. Internal-TL measures calculated were Banister training impulse (bTRIMP), Edwards TRIMP, Lucia TRIMP, individualized TRIMP (iTRIMP), and session RPE (sRPE). External-TL measures calculated were total distance, PlayerLoadâą, high-speed distance > 15 km/h, very-high-speed distance > 18 km/h, and individualized high-speed distance based on each playerâs vOBLA. Results: A second-order-regression (quadratic) analysis found that bTRIMP (R 2 = .78, P = .005) explained 78% of the variance and iTRIMP (R 2 = .55, P = .063) explained 55% of the variance in changes in VO 2 max. All other HR-based internal-TL measures and sRPE explained less than 40% of variance with fitness changes. External TL explained less than 42% of variance with fitness changes. Conclusions: In rugby players, bTRIMP and iTRIMP display a curvilinear dose-response relationship with changes in maximal aerobic fitness
Comparing Types Of Adaptive Automation Within A Multi-tasking Environment
Throughout the many years of research examining the various effects of automation on operator performance, stress, workload, etc., the focus has traditionally been on the level of automation, and the invocation methods used to alter it. The goal of the current study is to instead examine the utilization of various types of automation with the goal of better meeting the operatorâs cognitive needs, thus improving their performance, workload, and stress. The task, control of a simulated unmanned robotic system, is designed to specifically stress the operatorâs visual perception capabilities to a greater degree. Two types of automation are implemented to support the operatorâs performance of the task: an auditory beep aid intended to support visual perception resources, and a driving aid automating control of the vehicleâs navigation, offloading physical action execution resources. Therefore, a comparison can be made between types of automation intended to specifically support the mental dimension that is under the greatest demand (the auditory beep) against those that do not (the driving automation). An additional evaluation is made to determine the benefit of adaptively adjusting the level of each type of automation based on the current level of task demand, as well as the influence of individual differences in personality. Results indicate that the use of the auditory beep aid does improve performance, but also increases Temporal Demand and Effort. Use of driving automation appears to disengage the operator from the task, eliciting a vigilance response. Adaptively altering the level of automation to meet task demands has a mixed effect on performance and workload (reducing both) when the auditory beep automation is used. However, adaptive driving automation is clearly detrimental, iv causing an increase in workload while decreasing performance. Higher levels of Neuroticism are related to poorer threat detection performance, but personality differences show no indication of moderating the effects of either of the experimental manipulations. The results of this study show that the type of automation implemented within an environment has a considerable impact on the operator, in terms of performance as well as cognitive/emotional stat
Reductive Dechlorination of Toxic Chlorocarbons
The sodium hydride based reducing agents were prepared the method of Caubere (Angew. Chem. Int. Ed. Engl., 1983, 22, 599-613). Reagents were prepared containing nickel, iron and zinc metals. All were effective in dechlorinating 1,3-dichlorobenzene, 4-methoxy-chlorobenzene, and arochlor 1254. Most work focused on nickel based reagents, the most active. The nickel-based reducing agent used in THF at 65°C reduced to 200 ppm 1,3-dichlorobenzene (to benzene) and arochlor 1254 (to biphenyl) to below 0.2 ppm in less than 15 minutes. A two stage reduction reduced arochlor 1254 to below a detectable level as determined by gas chromatography using f.i.d. detector. Using 1,3-dichlorobenzene as a model showed that the first halogen is reduced more rapidly. Accordingly, 4-methoxy-chlorobenzne was reduced to methoxybenzene less efficiently--but polychlorinated ethers are expected to react rapidly. The presence of water reduced the activity of the Ni catalyst--i.e.--reduced the rate of dechlorination. Two staged reductions of 1,3-dichlorobenzene using iron and zinc based catalysts at 65°, 1 hr per stage, gave more than 99% reduction. Use of the Ni based reagent as catalyst with hydrogen at 2 atm as reducing agent converted 1,3-dichlorobenzene to benzene; rate data have yet to be taken. The overall results provide a base for some additional pilot studies using the iron and zinc based reagents with the aim of increasing the reagent activity. The results are expected to give clearer directions for a planned comprehensive study
The Effect of Air Quality on US Labor Market Participation
The adverse effects of deteriorating air quality on both human health and labor markets have become well-documented in epidemiological and economic literature. Health-conscious policymakers are presented with the challenge of implementing environmental regulations without causing substantial economic disturbance to industry employment, productivity, and wages. However, the social benefits of better health outcomes may correspond with economic benefits that outweigh the costs. Using data from the Current Population Survey and the Environmental Protection Agencyâs Air Quality Index, this study uses a multivariate fixed effects regression approach to estimate the relationship between air quality and various measures of labor market participation across 101 metropolitan areas in the United States between 1994â2017. Understanding the reflection of health outcomes in labor market participation may assist the quantification of economic benefits and contribute to a cost-benefit analysis of regulation policy. Empirical analysis suggests that variation in air quality has a negligible impact on US labor markets
HEIDE: An IDE for the Homomorphic Encryption Library HElib
Work in the field of Homomorphic Encryption has exploded in the past 5 years, after Craig Gentry proposed the first encryption scheme capable of performing Homomorphic Encryption. Under the scheme one can encrypt data, perform computations on the encrypted result (without needing the original data), and then decrypt the data to get the result as if the computations had been run on the unencrypted data.
Such a scheme has wide reaching implications for cloud computing. Computations on sensitive data, just like regular data, could now be performed in the cloud with the added security that even the cloud service provider couldn\u27t see the secure data. With such a benefit one might ask why the encryption scheme is not used currently? It is because, while Craig Gentry\u27s scheme was theoretically sound, it was not quick. As such, recent work has been in finding ways to speed up the scheme. Several improvements in speed have been made and several implementations of those improved schemes have been developed: one being HElib.
As of now HElib is self described as an assembly language for HE . Our work focused on creating HEIDE, a Homomorphic Encryption IDE, where researchers could write tests at a high-level. This high-level code is then compiled into the operations provided by HElib. HElib, like most encryption schemes, can be configured using different setup parameters. These parameters change the run-time and security of the scheme. As such we have also provided an easy way for researchers to simultaneously run their tests using different setup parameters. To support that, timing and memory metrics are provided for each test so that researchers can determine which parameters worked best
MS 044 Guide to H. Grant Taylor, MD Papers (1925-1992)
Papers consist primarily of personal and professional correspondence; board meeting and committee meeting minutes and reports; drafts, manuscripts, and published professional papers; documentation chronicling his role with the Atomic Bomb Casualty Commission (ABCC) in Japan, his role in the organization and development of a regional medical plan centered in Houston, of the University of Texas (UT) Postgraduate School of Medicine and its Division of Continuing Education, and of M. D. Anderson Hospital and Tumor Institute (MDAH), currently known as UT M. D. Anderson Cancer Center, and its renowned Department of Pediatrics. See more at MS 044
Applying wind simulations for planning and operation of real-time thermal ratings.
Real-time thermal ratings (RTTRs) are an emerging technology that allows the rating of electrical conductors to be estimated using real-time local weather observations. In many cases this leads to a very significant (typically 50%-100%) increase in rating with respect to conventional approaches. Conductor rating is heavily influenced by wind speed and direction. Consequently, in this paper, computational wind simulations commonly employed by the wind energy industry have been applied to inform rating estimation during network planning and operation. This provides an exciting opportunity to allow the identification of determining conductor spans to inform network designers of the rating potential of different conductor routes to estimate the additional wind energy that could be accommodated through the enhanced line rating and to allow intelligent placement of the monitoring equipment required to implement RTTR. The wind simulation data were also used to allow more accurate estimation of conductor ratings during operation. Two case studies taken from actual trial sites in the U.K. are presented to demonstrate that these techniques can provide a real world benefit
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