919 resultados para non-exhaustible energy


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Objective: We investigate the influence of caloric and protein deficit on mortality and length of hospital stay of critically ill patients. Methods: A cohort prospective study including 100 consecutive patients in a tertiary intensive care unit (ICU) receiving enteral or parenteral nutrition. The daily caloric and protein deficit were collected each day for a maximum of 30 days. Energy deficits were divided into critical caloric deficit (≥ 480 kcal/day) and non-critical caloric deficit (≤ 480 kcal/day); and in critical protein deficit (≥ 20 g/day) and non-critical protein deficit (≤ 20 g/day). The findings were correlated with hospital stay and mortality. Results: The mortality rate was 33%. Overall, the patients received 65.4% and 67.7% of the caloric and protein needs. Critical caloric deficit was found in 72% of cases and critical protein deficit in 70% of them. There was a significant correlation between length of stay and accumulated caloric deficit (R = 0.37; p < 0.001) and protein deficit (R = 0.28; p < 0.001). The survival analysis showed that mortality was greater in patients with both critical caloric (p < 0.001) and critical protein deficits (p < 0.01). The Cox regression analysis showed that critical protein deficit was associated with higher mortality (HR 0.25, 95% CI 0.07-0.93, p = 0.03). Conclusions: The incidence of caloric and protein deficit in the ICU is high. Both caloric and protein deficits increase the length of hospital stay, and protein deficit greater than 20 g/day is an independent factor for mortality in critical care unit.

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Security provisioning is an essential part in the design of any communication systems, which becomes more critical for wireless systems. Devising a quality of service (QoS) mechanism to coexist security algorithms is a daunting, yet inevitable task. The aim of this novel research article is to present a novel energy efficient, cross-layer-based application-layer wireless system with simultaneous security and QoS supports, which revolves around the practical and low-cost implementation of Suite-B cryptographic algorithms (promulgated by the National Security Agency) and detailed analyses of the associated complexities. The focus of this article is on the novel cross-layer mechanism and its effectiveness to handle QoS-enabled treatment while offering security enhancements.

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Forbidden disulfides are stressed disulfides found in recognisable protein contexts previously defined as structurally forbidden. The torsional strain of forbidden disulfides is typically higher than for structural disulfides, but not so high as to render them immediately susceptible to reduction under physionormal conditions. The meta-stability of forbidden disulfides makes them likely candidates as redox switches. Here we mined the Protein Data Bank for examples of the most common forbidden disulfide, the aCSDn. This is a canonical motif in which disulfide-bonded cysteine residues are positioned directly opposite each other on adjacent anti-parallel β-strands such that the backbone hydrogen bonded moieties are directed away from each other. We grouped these aCSDns into homologous clusters and performed an extensive physicochemical and informatic analysis of the examples found. We estimated their torsional energies using quantum chemical calculations and studied differences between the preferred conformations of the computational model and disulfides found in solved protein structures to understand the interaction between the forces imposed by the disulfide linkage and typical constraints of the surrounding β-sheet. In particular, we assessed the twisting, shearing and buckling of aCSDn-containing β-sheets, as well as the structural and energetic relaxation when hydrogen bonds in the motif are broken. We show the strong preference of aCSDns for the right-handed staple conformation likely arises from its compatibility with the twist, shear and Cα separation of canonical β-sheet. The disulfide can be accommodated with minimal distortion of the sheet, with almost all the strain present as torsional strain within the disulfide itself. For each aCSDn cluster, we summarise the structural and strain data, taxonomic conservation and any evidence of redox activity. aCSDns are known substrates of thioredoxin-like enzymes. This, together with their meta-stability, means they are ideally suited to biological switching roles and are likely to play important roles in the molecular pathways of oxidative stress.

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Sedentary screen time may be an important determinant of childhood obesity. A number of potential mechanisms to explain the link between screen time and increased bodyweight have been proposed; however, the relationship appears to be best explained by the effects on dietary intake, which is attributed to either food advertising or effects independent of food advertising. Technological advances have allowed for greater accessibility and exposure to advertisement-free screen-based media. This review was conducted to systematically synthesise the evidence from laboratory based studies which have investigated the non-advertising effects of screen time (TV viewing, sedentary video games, and computer use) on dietary intake in children, adolescents, and young adults. MEDLINE, PubMed, PsychInfo, CINAHL, and Embase were searched from inception through 5 July 2013. Ten trials met the inclusion criteria and were included in the review. Risk of study bias was judged to range from low to high. Screen time in the absence of food advertising was consistently found to be associated with increased dietary intake compared with non-screen behaviours. Suggested explanations for this relationship included: distraction, interruption of physiologic food regulation, screen time as a conditioned cue to eat, disruption of memory formation, and the effects of the stress-induced reward system. Due to the limited number of high-quality studies available for this review, our findings are preliminary. More work is required to better establish the link between dietary intake and advertisement-free screen time and assess whether differences exist between the different screen-based activities.

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This paper extends the conditions of the cluster-based routing protocols in terms of general algorithm complexity of data fusion, general compressing ratio of data fusion, and network area with long distance. Corresponding three general evaluation methods to evaluate the energy efficiency of the cluster-based routing protocols such as LEACH, PEGASIS, and BCDCP are provided. Moreover, three facts are found in them: (1) High-level software energy macro model is used to compute the energy dissipation of general data fusion software and make the constant value of energy dissipation of 1-bit data fusion an especial instance. (2) Multi-hop energy efficiency is related to the radio hardware parameters and the dynamic topology of network and the above protocols do not exploit the best use of the energy efficiency of multi-hop scheme. (3) High-energy dissipation non-cluster-head nodes, whose number changes with the density of the sensor nodes in clusters, worsen the death of nodes. The numerical results of experiments reprove these discoveries. Furthermore, they provide helpful guide for improving the above routing protocols to extent their application ranges.

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Two solution processable, non-fullerene electron acceptors, 2,2′-(((2,7-dioctyl-1,3,6,8-tetraoxo-1,2,3,6,7,8-exahydrobenzo[lmn][3,8]phenanthroline-4,9-diyl)bis(thiophene-5,2-diyl))bis(methanylylidene))dimalononitrile (R1) and (2Z,2′Z)-3,3′-((2,7-dioctyl-1,3,6,8-tetraoxo-1,2,3,6,7,8-hexahydrobenzo[lmn][3,8]phenanthroline-4,9-diyl)bis(thiophene-5,2-diyl))bis(2-(4-nitrophenyl) acrylonitrile) (R2), comprised of central naphthalene diimide and two different terminal accepting functionalities, malononitrile and 2-(4-nitrophenyl)acetonitrile, respectively, were designed and synthesised. The central and terminal accepting functionalities were connected via a mild conjugated thiophene linker. Both of the new materials (R1 and R2) displayed high thermal stability and were found to have energy levels matching those of the archetypal electron donor poly(3-hexylthiophene). A simple, solution-processable bulk-heterojunction device afforded a promising power conversion efficiency of 2.24% when R2 was used as a non-fullerene electron acceptor along with the conventional donor polymer poly(3-hexylthiophene). To the best of our knowledge, the materials reported herein are the first examples in the literature where synchronous use of such accepting blocks is demonstrated for the design and development of efficient non-fullerene electron acceptors.

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Through the conjunction of tetraphenylethylene and diketopyrrolopyrrole functionalities, a novel four-directional non-fullerene electron acceptor (denoted as 4D) was designed, synthesized and characterized. The new chromophore is highly soluble (for instance >30 mg mL(-1) in o-dichlorobenzene), thermally stable, and exhibits energy levels matching those of the conventional and routinely used donor polymer poly(3-hexyl thiophene). A power conversion efficiency of 3.86% was obtained in solution-processable bulk-heterojunction devices with a very high open circuit voltage of 1.18 V.

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The production of carbon fiber, particularly the oxidation/stabilization step, is a complex process. In the present study, a non-linear mathematical model has been developed for the prediction of density of polyacrylonitrile (PAN) and oxidized PAN fiber (OPF), as a key physical property for various applications, such as energy and material optimization, modeling, and design of the stabilization process. The model is based on the available functional groups in PAN and OPF. Expected functional groups, including [Formula presented], [Formula presented], –CH2, [Formula presented], and [Formula presented], were identified and quantified through the full deconvolution analysis of Fourier transform infrared attenuated total reflectance (FT-IR ATR) spectra obtained from fibers. These functional groups form the basis of three stabilization rendering parameters, representing the cyclization, dehydrogenation and oxidation reactions that occur during PAN stabilization, and are used as the independent variables of the non-linear predictive model. The k-fold cross validation approach, with k = 10, has been employed to find the coefficients of the model. This model estimates the density of PAN and OPF independent of operational parameters and can be expanded to all operational parameters. Statistical analysis revealed good agreement between the governing model and experiments. The maximum relative error was less than 1% for the present model.

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There remains much controversy over the role of non-caloric sweeteners (NCS) in the food supply. Are they helpful or do they promote overconsumption? There is a lack of evidence demonstrating a meaningful causal relationship between consuming NCS products and changes in calorie intake. Does this mean that the decoupling of energy from sweetness actually has no long-term benefit 0 11 consumers' energy regulation?

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In order for sodium batteries to become a safe, lower cost option for large scale energy storage, minimising the price of all components is important. We report here on the application of a pyrrolidinium room temperature ionic liquid comprising the dicyanamide anion as a successful electrolyte system for sodium metal batteries that does not contain expensive fluorinated species. The effects of plating/stripping of sodium from Na metal electrodes has been investigated in a symmetrical Na | electrolyte | Na configuration at a current density of 10 μA cm− 2. Comparisons are drawn to reference organic electrolytes comprising propylene carbonate-fluoroethylene carbonate. Residual water molecules in the ionic liquid electrolyte are observed to have a significant effect upon the surface film and subsequent favourable plating/stripping behaviour of symmetrical cells and this is explored in detail. An increase of the moisture content from 90 ppm to 400 ppm impedes both electrodeposition and electrodissolution of the Na+/Na. This is investigated at Ni electrodes using cyclic voltammetry at different Na+-salt concentrations to further understand the mechanism.

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The fatigue lives are reduced accompanying an additional cyclic hardening under strain controlled non-proportional cyclic loading in which principal directions of stress and strain are altered within a cycle. This study predicts non-proportional cyclic hardening and multiaxial fatigue life for several BCC and FCC metals under constant amplitude strain cycling. A novel procedure to determine non-proportional cyclic hardening form uniaxial tensile properties has discussed in this study. Standard plastic strain energy density based fatigue criteria with considering the non-proportional cyclic hardening effect successfully predicts multiaxial fatigue lives. The predictions of non-proportional cyclic hardening and multiaxial fatigue life through models are validated by experimental results of various BCC and FCC metals which are collected from literatures.

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By employing interpretive policy analysis this thesis aims to assess, measure, and explain policy capacity for government and non-government organizations involved in reclaiming Alberta's oil sands. Using this type of analysis to assess policy capacity is a novel approach for understanding reclamation policy; and therefore, this research will provide a unique contribution to the literature surrounding reclamation policy. The oil sands region in northeast Alberta, Canada is an area of interest for a few reasons; primarily because of the vast reserves of bitumen and the environmental cost associated with developing this resource. An increase in global oil demand has established incentive for industry to seek out and develop new reserves. Alberta's oil sands are one of the largest remaining reserves in the world, and there is significant interest in increasing production in this region. Furthermore, tensions in several oil exporting nations in the Middle East remain unresolved, and this has garnered additional support for a supply side solution to North American oil demands. This solution relies upon the development of reserves in both the United States and Canada. These compounding factors have contributed to the increased development in the oil sands of northeastern Alberta. Essentially, a rapid expansion of oil sands operations is ongoing, and is the source of significant disturbance across the region. This disturbance, and the promises of reclamation, is a source of contentious debates amongst stakeholders and continues to be highly visible in the media. If oil sands operations are to retain their social license to operate, it is critical that reclamation efforts be effective. One concern non-governmental organizations (NGOs) expressed criticizes the current monitoring and enforcement of regulatory programs in the oil sands. Alberta's NGOs have suggested the data made available to them originates from industrial sources, and is generally unchecked by government. In an effort to discern the overall status of reclamation in the oil sands this study explores several factors essential to policy capacity: work environment, training, employee attitudes, perceived capacity, policy tools, evidence based work, and networking. Data was collected through key informant interviews with senior policy professionals in government and non-government agencies in Alberta. The following are agencies of interest in this research: Canadian Association of Petroleum Producers (CAPP); Alberta Environment and Sustainable Resource Development (AESRD); Alberta Energy Regulator (AER); Cumulative Environmental Management Association (CEMA); Alberta Environment Monitoring, Evaluation, and Reporting Agency (AEMERA); Wood Buffalo Environmental Association (WBEA). The aim of this research is to explain how and why reclamation policy is conducted in Alberta's oil sands. This will illuminate government capacity, NGO capacity, and the interaction of these two agency typologies. In addition to answering research questions, another goal of this project is to show interpretive analysis of policy capacity can be used to measure and predict policy effectiveness. The oil sands of Alberta will be the focus of this project, however, future projects could focus on any government policy scenario utilizing evidence-based approaches.

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Non-intrusive monitoring of health state of induction machines within industrial process and harsh environments poses a technical challenge. In the field, winding failures are a major fault accounting for over 45% of total machine failures. In the literature, many condition monitoring techniques based on different failure mechanisms and fault indicators have been developed where the machine current signature analysis (MCSA) is a very popular and effective method at this stage. However, it is extremely difficult to distinguish different types of failures and hard to obtain local information if a non-intrusive method is adopted. Typically, some sensors need to be installed inside the machines for collecting key information, which leads to disruption to the machine operation and additional costs. This paper presents a new non-invasive monitoring method based on GMRs to measure stray flux leaked from the machines. It is focused on the influence of potential winding failures on the stray magnetic flux in induction machines. Finite element analysis and experimental tests on a 1.5-kW machine are presented to validate the proposed method. With time-frequency spectrogram analysis, it is proven to be effective to detect several winding faults by referencing stray flux information. The novelty lies in the implement of GMR sensing and analysis of machine faults.

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Dust attenuation affects nearly all observational aspects of galaxy evolution, yet very little is known about the form of the dust-attenuation law in the distant universe. Here, we model the spectral energy distributions of galaxies at z ~ 1.5–3 from CANDELS with rest-frame UV to near-IR imaging under different assumptions about the dust law, and compare the amount of inferred attenuated light with the observed infrared (IR) luminosities. Some individual galaxies show strong Bayesian evidence in preference of one dust law over another, and this preference agrees with their observed location on the plane of infrared excess (IRX, L_TIR/L_UV) and UV slope (β). We generalize the shape of the dust law with an empirical model, A_ λ,σ =E(B-V)k_ λ (λ / λ v)^ σ where k_λ is the dust law of Calzetti et al., and show that there exists a correlation between the color excess E(B-V) and tilt δ with δ =(0.62±0.05)log(E(B-V))+(0.26±0.02). Galaxies with high color excess have a shallower, starburst-like law, and those with low color excess have a steeper, SMC-like law. Surprisingly, the galaxies in our sample show no correlation between the shape of the dust law and stellar mass, star formation rate, or β. The change in the dust law with color excess is consistent with a model where attenuation is caused by scattering, a mixed star–dust geometry, and/or trends with stellar population age, metallicity, and dust grain size. This rest-frame UV-to-near-IR method shows potential to constrain the dust law at even higher redshifts (z>3).

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Avec la disponibilité de capteurs fiables de teneur en eau exploitant la spectroscopie proche infrarouge (NIR pour near-infrared) et les outils chimiométriques, il est maintenant possible d’appliquer des stratégies de commande en ligne sur plusieurs procédés de séchage dans l’industrie pharmaceutique. Dans cet ouvrage, le séchage de granules pharmaceutiques avec un séchoir à lit fluidisé discontinu (FBD pour fluidized bed dryer) de taille pilote est étudié à l’aide d’un capteur d’humidité spectroscopique. Des modifications électriques sont d’abord effectuées sur le séchoir instrumenté afin d’acheminer les signaux mesurés et manipulés à un périphérique d’acquisition. La conception d’une interface homme-machine permet ensuite de contrôler directement le séchoir à l’aide d’un ordinateur portable. Par la suite, un algorithme de commande prédictive (NMPC pour nonlinear model predictive control), basée sur un modèle phénoménologique consolidé du FBD, est exécuté en boucle sur ce même ordinateur. L’objectif est d’atteindre une consigne précise de teneur en eau en fin de séchage tout en contraignant la température des particules ainsi qu’en diminuant le temps de lot. De plus, la consommation énergétique du FBD est explicitement incluse dans la fonction objectif du NMPC. En comparant à une technique d’opération typique en industrie (principalement en boucle ouverte), il est démontré que le temps de séchage et la consommation énergétique peuvent être efficacement gérés sur le procédé pilote tout en limitant plusieurs problèmes d’opération comme le sous-séchage, le surséchage ou le surchauffage des granules.