56 resultados para up-and-down method


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This paper deals with proposal of a new dual stack approach for reducing both leakage and dynamic powers. The development of digital integrated circuits is challenged by higher power consumption. Thecombination of higher clock speeds, greater functional integration, and smaller process geometries has contributed to significant growth in power density. Scaling improves transistor density and functionality ona chip. Scaling helps to increase speed and frequency of operation and hence higher performance. As voltages scale downward with the geometries threshold voltages must also decrease to gain the performance advantages of the new technology but leakage current increases exponentially. Today leakage power has become anincreasingly important issue in processor hardware and software design. It can be used in various applications like digital VLSI clocking system, buffers, registers, microprocessors etc. The leakage power increases astechnology is scaled down. In this paper, we propose a new dual stack approach for reducing both leakage and dynamic powers. Moreover, the novel dual stack approach shows the least speed power product whencompared to the existing methods. All well known approach is “Sleep” in this method we reduce leakage power. The proposed Dual Stack approach we reduce more power leakage. Dual Stack approach uses theadvantage of using the two extra pull-up and two extra pull-down transistors in sleep mode either in OFF state or in ON state. Since the Dual Stack portion can be made common to all logic circuitry, less number of transistors is needed to apply a certain logic circuit.The dual stack approach shows the least speed power product among all methods. The Dual Stack technique provides new ways to designers who require ultra-low leakage power consumption with much less speedpower product.

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Recognizing a class of movements as belonging to a "nominal" action category, such as walking, running, or throwing, is a fundamental human ability. Three experiments were undertaken to test the hypothesis that common ("prototypical") features of moving displays could be learned by observation. Participants viewed moving stick-figure displays resembling forearm flexion movements in the saggital plane. Four displays (presentation displays) were first presented in which one or more movement dimensions were combined with 2 respective cues: direction (up, down), speed (fast, slow), and extent (long, short). Eight test displays were then shown, and the observer indicated whether each test display was like or unlike those previously seen. The results showed that without corrective feedback, a single cue (e.g., up or down) could be correctly recognized, on average, with the proportion correct between .66 and .87. When two cues were manipulated (e.g., up and slow), recognition accuracy remained high, ranging between .72 and .89. Three-cue displays were also easily identified. These results provide the first empirical demonstration of action-prototype learning for categories of human action and show how apparently complex kinematic patterns can be categorized in terms of common features or cues. It was also shown that probability of correct recognition of kinematic properties was reduced when the set of 4 presentation displays were more variable with respect to their shared kinematic property, such as speed or amplitude. Finally, while not conclusive, the results (from 2 of the 3 experiments) did suggest that similarity (or "likeness") with respect to a common kinematic property (or properties) is more easily recognized than dissimilarity.

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Background: Reliability or validity studies are important for the evaluation of measurement error in dietary assessment methods. An approach to validation known as the method of triads uses triangulation techniques to calculate the validity coefficient of a food-frequency questionnaire (FFQ).

Objective:
To assess the validity of an FFQ estimates of carotenoid and vitamin E intake against serum biomarker measurements and weighed food records (WFRs), by applying the method of triads. Design: The study population was a sub-sample of adult participants in a randomised controlled trial of b-carotene and sunscreen in the prevention of skin cancer. Dietary intake was assessed by a self-administered FFQ and a WFR. Nonfasting blood samples were collected and plasma analysed for five carotenoids (a-carotene, b-carotene, b-cryptoxanthin, lutein, lycopene) and vitamin E. Correlation coefficients were calculated between each of the dietary methods and the validity coefficient was calculated using
the method of triads. The 95% confidence intervals for the validity coefficients were estimated using bootstrap sampling.

Results: The validity coefficients of the FFQ were highest for a-carotene (0.85) and lycopene (0.62), followed by b-carotene (0.55) and total carotenoids (0.55), while the lowest validity coefficient was for lutein (0.19). The method of triads could not be used for b-cryptoxanthin and vitamin E, as one of the three underlying correlations was negative.

Conclusions:
Results were similar to other studies of validity using biomarkers and the method of triads. For many dietary factors, the upper limit of the validity coefficients was less than 0.5 and therefore only strong relationships between dietary exposure and disease will be detected.

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The increasing use of team assignments within higher education is well documented. The driving forces behind this include desires to facilitate reflective and collaborative learning, to develop generic teamwork skills for graduate employment and to reduce the grading workloads of faculty staff. Students however consistently report dissatisfaction when the assessment of team assignments produces a common grade for all team members. Self-andpeer-assessment (SAPA) is presented as a fair, valid and reliable method of producing information about ongoing team processes. This information can provide ongoing feedback to team members and rich formative data to instructors attempting to assess the team process and students’ teamwork skills. This data can also enable individualised summative assessment in dysfunctional teams or situations of uneven team member contributions. Whilst manual SAPA protocols can work effectively for smaller classes, computer-assisted SAPA offers a solution to the problems of large classes. This paper reports on the early stages of an online SAPA tool, originally developed for small classes of architecture students, adapted for use by very large business communication classes comprising up to 1000 students in a semester. This large unit is delivered on four Australian campuses as well as off-campus and in off-shore mode, by up to fourteen instructors at any one time. The paper documents how three researchers from very different backgrounds worked to create their own research team, implement a pilot study, and adapt the online tool, whilst adhering to comparability of assessment constraints and maintaining integrity of research design.

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Cellular lipids frequently co-purify with lipid binding proteins isolated from tissue extracts or heterologous host systems and as such hinder in vitro ligand binding approaches for which the apo-protein is a prerequisite. Here we present a technique for the complete removal of unesterified fatty acids, phospholipids, steroids and other lipophilic ligands bound to soluble proteins, without protein denaturation. Peroxisome proliferator activated receptor gamma ligand binding domain and intracellular fatty acid binding proteins were expressed in an Escherichia coli host and completely delipidated by hydrophobic interaction chromatography using phenyl sepharose. The delipidation procedure operates at room temperature with complete removal of bound lipids in a single step, as ascertained by mass spectrometry analysis of organic solvent extracts from purified protein samples. The speed and capacity of this method makes it amenable to scale-up and high-throughput applications. The method can also easily be adapted for other lipid binding proteins that require delipidation under native conditions.

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A variety of techniques for extracting carotenoids from the marine Thraustochytrium sp. ONC-T18 was compared. Specifically, the organic solvents acetone, ethyl acetate, and petroleum ether were tested, along with direct and indirect ultrasonic assisted extraction (probe vs bath) methods. Techniques that used petroleum ether/acetone/water (15:75:10, v/v/v) with 3 h of agitation, or 5 min in an ultrasonic bath, produced the highest extraction yields of total carotenoids (29−30.5 μg g-1). Concentrations up to 11.5 μg g-1 of canthaxanthin and 17.5 μg g-1 of β-carotene were detected in extracts stored for 6 weeks. Astaxanthin and echinenone were also detected as minor compounds. Extracts with and without antioxidants showed similar carotenoid concentration profiles. However, total carotenoid concentrations were approximately 8% higher when antioxidants were used. Finally, an easy-to-perform and inexpensive method to detect co-enzymes in ONC-T18 was also developed using silica gel TLC plates. Five percent methanol in toluene as a mobile phase consistently eluted co-enzyme Q10 standards and could separate the co-enzyme fractions present in ONC-T18.

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Aim: Costs associated with mental health treatment for young persons at 'ultra' high risk (UHR) of developing a psychotic disorder have not previously been reported. This paper reports cost implications of providing psychological and pharmacological intervention for individuals at UHR for psychosis compared with minimal psychological treatment.

Method: Mental health service costs associated with a randomized controlled trial of two treatments (Specific Preventive Intervention: SPI and Needs-Based Intervention: NBI) for UHR young persons were estimated and compared at three time points: treatment phase, short-term follow up and medium-term follow up.

Results: Although the SPI group incurred significantly higher treatment costs than the NBI group over the treatment phase, they incurred significantly lower outpatient treatment costs over the longer term.

Conclusion: This study indicates that specific interventions designed to treat young persons who are identified as being at UHR of psychosis might be associated with some cost savings compared with non-specific interventions.

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We present a facile and effective method for controlling the surface hydrophobicity of polyimide films from sticky to superhydrophobic properties by tailoring their topographies. Nanostructured silver layers were produced on polyimide films by treatment with aqueous KOH and AgNO3, followed by thermal treatment at 200 degrees C or higher temperatures. Further modification of the gold-coated silver layers with n-dodecanethiol led to hydrophobic surfaces. Different morphologies of the silver layers at the micro- and nano-meter scales, which result in the variety of hydrophobicity, can be tailored by controlling the thermal treatment temperature. Surfaces prepared at 320 degrees C showed a sticky property that water drops did not slide off even when the sample was held upside down. Superhydrophobic surfaces were obtained when the temperature was above 340 degrees C. A remarkable superhydrophobicity, as evidenced by a very large water contact angle of 162 degrees and a very small sliding angle of 7 degrees, was achieved by heating the modified polyimide films at 360 degrees C. This is also the first example for superhydrophobic modification of polyimide films.

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Dietary lipids and fatty acids are not only fundamental in determining animal performance, but also determine the eating qualities of animal products. Several methods have been used to quantify fatty acid metabolism but most involve expensive in vitro approaches that are not suitable for most laboratories. Furthermore, there is considerable variation between methods with regard to enzyme activity, which makes comparison of results between studies difficult. The recently developed whole-body fatty acid balance method (WBFABM) is a simple and reliable in vivo method for assessing fatty acid metabolism, including rates of liponeogenesis and de novo fatty acid production, β-oxidation of fatty acids and bioconversion (elongation and desaturation) of fatty acids to long-chain polyunsaturated fatty acids. Initially developed for implementation with a fish model, the WBFABM has proven to be a simple and effective method that can be used in any laboratory equipped with a gas chromatography unit. Since its development, it has been used in several farmed finfish feeding trials and in broiler chicken feeding trials. The WBFABM is currently used at research institutions worldwide and its use is increasing in popularity among animal scientists. With this method, it is possible to track the fate of individual dietary fatty acids within the body. The WBFABM could contribute significantly to information generated by animal feeding trials.

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Recently, a simple yet powerful branch-and-bound method called Efficient Subwindow Search (ESS) was developed to speed up sliding window search in object detection. A major drawback of ESS is that its computational complexity varies widely from O(n2) to O(n4) for n × n matrices. Our experimental experience shows that the ESS's performance is highly related to the optimal confidence levels which indicate the probability of the object's presence. In particular, when the object is not in the image, the optimal subwindow scores low and ESS may take a large amount of iterations to converge to the optimal solution and so perform very slow. Addressing this problem, we present two significantly faster methods based on the linear-time Kadane's Algorithm for 1D maximum subarray search. The first algorithm is a novel, computationally superior branchand- bound method where the worst case complexity is reduced to O(n3). Experiments on the PASCAL VOC 2006 data set demonstrate that this method is significantly and consistently faster (approximately 30 times faster on average) than the original ESS. Our second algorithm is an approximate algorithm based on alternating search, whose computational complexity is typically O(n2). Experiments shows that (on average) it is 30 times faster again than our first algorithm, or 900 times faster than ESS. It is thus wellsuited for real time object detection.

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We apply a Markov switching model to investigate the possibility of an asymmetric causal relationship between the volatility process inferred from the iTraxx CDS options market and the implied volatility from the stock index options market. We find strong evidence that the stock market leads the CDS market and the effect of the implied stock market volatility is more significant during the volatile regime. We also find that a large jump in the stock return, up or down, may indeed be followed by a regime shift.

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Sustainable development is an international problem as it affects everyone everywhere.Up until recently, it has been pursued on a national scale leading from a confused understanding of sustainability from the international community. The various international summits and meetings on the topic have allowed establishment of general guidelines and attitudes that need to be taken by national policy writers. Because of the lack of understanding on the topic, as it encompasses many aspects of social, economic and environmental behaviours, there has been a general individual interpretation of these ideas that has then shaped national policies. These policies differ in nature and therefore must be analysed to identify these differences and their implications on the built environment. The Melbourne 2030 plan and the London plan are two of the leading and highly mentioned policies stemming from the advanced nature of the respective economies. These nations’ polices have implications that trickle down to the very core of building design and lead stakeholders in certain directions as opposed to others. The research attempts to highlight the paths taken by these different nations and what influence this has had on the overall state of sustainable development in the localised communities respectively. Analysing the state of sustainable development ideas from the international, to the national and down to the local policy strategies will give a clear picture of the state of policy direction in the localised context. Looking then at two buildings in these contexts identifies how policy can play a major role in shaping sustainable design related outcomes. The research finds that the UK and London plan is well-structured and pays close attention to the built environment while there is much less evidence of this in the Australia and Melbourne policy plans. This can be seen in the overall outcome of the chosen building case studies where the chosen London building shows more promise in its sophisticated use of technologies to achieve a highly sustainable building as compared to the chosen Melbourne building. It has been suggested that because of the differences in rating tools and their applications, there may be problems in successfully comparing two buildings in different contexts. This gives rise to the question of global sustainability where it is understood that sustainability is a global problem and cannot be tackled on a fragmented basis. This then may suggest that the international stage of sustainable understanding should be holistic in that it should be tackled at a global stage instead of the current fragmented national stage.

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This study aimed to establish optimal conditions for a cell culture system that would allow the measurement of 18:3n-3 (ALA) bioconversion into n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA), and to determine the overall pathway kinetics. Using rat hepatocytes (FaO) as model cells, it was established that a maximum 20:5n-3 (EPA) production from 50 mM ALA initial concentration was achieved after 3 days of incubation. Next, it was established that a gradual increase in the ALA concentration from 0 up to 125mM lead to a proportional increase in EPA, without concomitant increase in further elongated or desaturated products, such as 22:5n-3 (DPA) and 22:6n-3 (DHA) in 3 day incubations. Of interest, ALA bioconversion products were observed in the culture medium. Therefore, in vitro experiments disregarding the medium fatty acid content are underestimating the metabolism efficiency. The novel application of the fatty acid mass balance (FAMB) method on cell culture system (cells with medium) enabled quantifying the apparent enzymatic activities for the biosynthesis of n-3 LC-PUFA. The activity of the key enzymes was estimated and showed that, under these conditions, 50% (Km) of the theoretical maximal (Vmax = 3654 mmol.g21 of cell protein.hour21) Fads2 activity on ALA can be achieved with 81 mM initial ALA. Interestingly, the apparent activity of Elovl2 (20:5n-3 elongation) was the slowest amongst other biosynthesis steps. Therefore, the possible improvement of Elovl2 activity is suggested toward a more efficient DHA production from ALA. The present study proposed and described an ad hoc optimised cell culture conditions and methodology towards achieving a reliable experimental platform, using FAMB, to assist in studying the efficiency of ALA bioconversion into n-3 LC-PUFA in vitro. The FAMB proved to be a powerful and inexpensive method to generate a detailed description of the kinetics of n-3 LC-PUFA biosynthesis enzymes activities in vitro.

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In this paper, hidden Markov models (HMM) is studied for spike sorting. We notice that HMM state sequences have capability to represent spikes precisely and concisely. We build a HMM for spikes, where HMM states respect spike significant shape variations. Four shape variations are introduced: silence, going up, going down and peak. They constitute every spike with an underlying probabilistic dependence that is modelled by HMM. Based on this representation, spikes sorting becomes a classification problem of compact HMM state sequences. In addition, we enhance the method by defining HMM on extracted Cepstrum features, which improves the accuracy of spike sorting. Simulation results demonstrate the effectiveness of the proposed method as well as the efficiency.

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Synthesis of molecular-level multiple-component composites are particularly challenging due to the lack of direct bonding among different components. In this study, molecular-level graphene oxide (GO)-polyacryl amide (PAM)-CeOx composites were successfully synthesized, using the simultaneous polymerization and crosslinking strategy. Attenuated total reflection Fourier transform infrared (ATR-FTIR) and nuclear magnetic resonance (NMR) techniques confirmed that polyacryl amide (PAM) chains were successfully grafted onto the surface of GO. X-ray photoelectron spectroscopic (XPS) and X-ray diffraction (XRD) analyses further revealed the characteristic signals of cerium elements and CeO2 phase respectively. Scanning electron microscopy (SEM) showed that the surface morphology of the GO-PAM-CeOx composites was substantially thicker and rougher than those of the original GO. Further exploration of the reaction mechanism clearly demonstrate the existence of strong chelating interaction among PAM chains and Ce(IV) ions. In particular, the polymerization of acryl amide monomers and the crosslinking reaction between PAM and Ce(IV) or Ce(III) ions were realized simultaneously, leading to the final formation of molecular-level GO-PAM-CeOx composites. Moreover, the as-synthesized GO-PAM-CeOx composites were capable of effectively decomposing Rhodamine B under simulated sunlight, making it a potential candidate as a new photo catalyst. To sum up, this report demonstrates the potential utility of simultaneous polymerization and crosslinking method for the synthesis of other multiple-component composites at molecular-level.