Enhanced Water Demand Analysis via Symbolic Approximation within an Epidemiology-Based Forecasting Framework

[EN] Epidemiology-based models have shown to have successful adaptations to deal with challenges coming from various areas of Engineering, such as those related to energy use or asset management. This paper deals with urban water demand, and data analysis is based on an Epidemiology tool-set herein developed. This combination represents a novel framework in urban hydraulics. Specifically, various reduction tools for time series analyses based on a symbolic approximate (SAX) coding technique able to deal with simple versions of data sets are presented. Then, a neural-network-based model that uses SAX-based knowledge-generation from various time series is shown to improve forecasting abilities. This knowledge is produced by identifying water distribution district metered areas of high similarity to a given target area and sharing demand patterns with the latter. The proposal has been tested with databases from a Brazilian water utility, providing key knowledge for improving water management and hydraulic operation of the distribution system. This novel analysis framework shows several benefits in terms of accuracy and performance of neural network models for water demand.Navarrete-López, CF.; Herrera Fernández, AM.; Brentan, BM.; Luvizotto Jr., E.; Izquierdo Sebastián, J. (2019). Enhanced Water Demand Analysis via Symbolic Approximation within an Epidemiology-Based Forecasting Framework. Water. 11(246):1-17. https://doi.org/10.3390/w11020246S11711246Fecarotta, O., Carravetta, A., Morani, M., & Padulano, R. (2018). Optimal Pump Scheduling for Urban Drainage under Variable Flow Conditions. Resources, 7(4), 73. doi:10.3390/resources7040073Creaco, E., & Pezzinga, G. (2018). Comparison of Algorithms for the Optimal Location of Control Valves for Leakage Reduction in WDNs. Water, 10(4), 466. doi:10.3390/w10040466Nguyen, K. A., Stewart, R. 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Heating and cooling of the neutral ISM in the NGC4736 circumnuclear ring

The manner in which gas accretes and orbits within circumnuclear rings has direct implications for the star formation process. In particular, gas may be compressed and shocked at the inflow points, resulting in bursts of star formation at these locations. Afterwards the gas and young stars move together through the ring. In addition, star formation may occur throughout the ring, if and when the gas reaches sufficient density to collapse under gravity. These two scenarios for star formation in rings are often referred to as the `pearls on a string' and `popcorn' paradigms. In this paper, we use new Herschel PACS observations, obtained as part of the KINGFISH Open Time Key Program, along with archival Spitzer and ground-based observations from the SINGS Legacy project, to investigate the heating and cooling of the interstellar medium in the nearby star-forming ring galaxy, NGC4736. By comparing spatially resolved estimates of the stellar FUV flux available for heating, with the gas and dust cooling derived from the FIR continuum and line emission, we show that while star formation is indeed dominant at the inflow points in NGC 4736, additional star formation is needed to balance the gas heating and cooling throughout the ring. This additional component most likely arises from the general increase in gas density in the ring over its lifetime. Our data provide strong evidence, therefore, for a combination of the two paradigms for star formation in the ring in NGC4736.Comment: accepted for publication in A&

Rapid reduction versus abrupt quitting for smokers who want to stop soon: a randomised controlled non-inferiority trial

Background: The standard way to stop smoking is to stop abruptly on a quit day with no prior reduction in consumption of cigarettes. Many smokers feel that reduction is natural and if reduction programmes were offered, many more might take up treatment. Few trials of reduction versus abrupt cessation have been completed. Most are small, do not use pharmacotherapy, and do not meet the standards necessary to obtain a marketing authorisation for a pharmacotherapy.\ud Design/Methods: We will conduct a non-inferiority andomised trial of rapid reduction versus standard abrupt cessation among smokers who want to stop smoking. In the reduction arm,participants will be advised to reduce smoking consumption by half in the first week and to 25% of baseline in the second, leading up to a quit day at which participants will stop smoking completely.This will be assisted by nicotine patches and an acute form of nicotine replacement therapy. In the abrupt arm participants will use nicotine patches only, whilst smoking as normal, for two weeks prior to a quit day, at which they will also stop smoking completely. Smokers in either arm will have standard withdrawal orientated behavioural support programme with a combination of nicotine patches and acute nicotine replacement therapy post-cessation.\ud Outcomes/Follow-up: The primary outcome of interest will be prolonged abstinence from smoking, with secondary trial outcomes of point prevalence, urges to smoke and withdrawal\ud symptoms. Follow up will take place at 4 weeks, 8 weeks and 6 months post-quit day

Transformation of spin information into large electrical signals via carbon nanotubes

Spin electronics (spintronics) exploits the magnetic nature of the electron, and is commercially exploited in the spin valves of disc-drive read heads. There is currently widespread interest in using industrially relevant semiconductors in new types of spintronic devices based on the manipulation of spins injected into a semiconducting channel between a spin-polarized source and drain. However, the transformation of spin information into large electrical signals is limited by spin relaxation such that the magnetoresistive signals are below 1%. We overcome this long standing problem in spintronics by demonstrating large magnetoresistance effects of 61% at 5 K in devices where the non-magnetic channel is a multiwall carbon nanotube that spans a 1.5 micron gap between epitaxial electrodes of the highly spin polarized manganite La0.7Sr0.3MnO3. This improvement arises because the spin lifetime in nanotubes is long due the small spin-orbit coupling of carbon, because the high nanotube Fermi velocity permits the carrier dwell time to not significantly exceed this spin lifetime, because the manganite remains highly spin polarized up to the manganite-nanotube interface, and because the interfacial barrier is of an appropriate height. We support these latter statements regarding the interface using density functional theory calculations. The success of our experiments with such chemically and geometrically different materials should inspire adventure in materials selection for some future spintronicsComment: Content highly modified. New title, text, conclusions, figures and references. New author include

The Preliminary Evaluation of Liquid Lubricants for Space Applications by Vacuum Tribometry

Four different vacuum tribometers for the evaluation of liquid lubricants for space applications are described. These range from simple ball-on-flat sliders with maximum in-situ control and surface characterization to an instrument bearing apparatus having no in-situ characterization. Thus, the former provides an abundance of surface chemical information but is not particularly simulative of most triboelements. On the other hand, the instrument bearing apparatus is completely simulative, but only allows post-mortem surface chemical information. Two other devices, a four-ball apparatus and a ball-on-plate tribometer, provide varying degrees of surface chemical information and tribo-simulation. Examples of data from each device are presented

Assessment of the Performance Potential of Advanced Subsonic Transport Concepts for NASA's Environmentally Responsible Aviation Project

NASA's Environmentally Responsible Aviation (ERA) project has matured technologies to enable simultaneous reductions in fuel burn, noise, and nitrogen oxide (NOx) emissions for future subsonic commercial transport aircraft. The fuel burn reduction target was a 50% reduction in block fuel burn (relative to a 2005 best-in-class baseline aircraft), utilizing technologies with an estimated Technology Readiness Level (TRL) of 4-6 by 2020. Progress towards this fuel burn reduction target was measured through the conceptual design and analysis of advanced subsonic commercial transport concepts spanning vehicle size classes from regional jet (98 passengers) to very large twin aisle size (400 passengers). Both conventional tube-and-wing (T+W) concepts and unconventional (over-wing-nacelle (OWN), hybrid wing body (HWB), mid-fuselage nacelle (MFN)) concepts were developed. A set of propulsion and airframe technologies were defined and integrated onto these advanced concepts which were then sized to meet the baseline mission requirements. Block fuel burn performance was then estimated, resulting in reductions relative to the 2005 best-in-class baseline performance ranging from 39% to 49%. The advanced single-aisle and large twin aisle T+W concepts had reductions of 43% and 41%, respectively, relative to the 737-800 and 777-200LR aircraft. The single-aisle OWN concept and the large twin aisle class HWB concept had reductions of 45% and 47%, respectively. In addition to their estimated fuel burn reduction performance, these unconventional concepts have the potential to provide significant noise reductions due, in part, to engine shielding provided by the airframe. Finally, all of the advanced concepts also have the potential for significant NOx emissions reductions due to the use of advanced combustor technology. Noise and NOx emissions reduction estimates were also generated for these concepts as part of the ERA project

Membranes with the Same Ion Channel Populations but Different Excitabilities

Electrical signaling allows communication within and between different tissues and is necessary for the survival of multicellular organisms. The ionic transport that underlies transmembrane currents in cells is mediated by transporters and channels. Fast ionic transport through channels is typically modeled with a conductance-based formulation that describes current in terms of electrical drift without diffusion. In contrast, currents written in terms of drift and diffusion are not as widely used in the literature in spite of being more realistic and capable of displaying experimentally observable phenomena that conductance-based models cannot reproduce (e.g. rectification). The two formulations are mathematically related: conductance-based currents are linear approximations of drift-diffusion currents. However, conductance-based models of membrane potential are not first-order approximations of drift-diffusion models. Bifurcation analysis and numerical simulations show that the two approaches predict qualitatively and quantitatively different behaviors in the dynamics of membrane potential. For instance, two neuronal membrane models with identical populations of ion channels, one written with conductance-based currents, the other with drift-diffusion currents, undergo transitions into and out of repetitive oscillations through different mechanisms and for different levels of stimulation. These differences in excitability are observed in response to excitatory synaptic input, and across different levels of ion channel expression. In general, the electrophysiological profiles of membranes modeled with drift-diffusion and conductance-based models having identical ion channel populations are different, potentially causing the input-output and computational properties of networks constructed with these models to be different as well. The drift-diffusion formulation is thus proposed as a theoretical improvement over conductance-based models that may lead to more accurate predictions and interpretations of experimental data at the single cell and network levels

Interleukin-1 polymorphisms associated with increased risk of gastric cancer

Helicobacter pylori infection is associated with a variety of clinical outcomes including gastric cancer and duodenal ulcer disease1. The reasons for this variation are not clear, but the gastric physiological response is influenced by the severity and anatomical distribution of gastritis induced by H. pylori. Thus, individuals with gastritis predominantly localized to the antrum retain normal (or even high) acid secretion2, whereas individuals with extensive corpus gastritis develop hypochlorhydria and gastric atrophy3, which are presumptive precursors of gastric cancer4. Here we report that interleukin-1 gene cluster polymorphisms suspected of enhancing production of interleukin-1-beta are associated with an increased risk of both hypochlorhydria induced by H. pylori and gastric cancer. Two of these polymorphism are in near-complete linkage disequilibrium and one is a TATA-box polymorphism that markedly affects DNA-protein interactions in vitro. The association with disease may be explained by the biological properties of interleukin-1-beta, which is an important pro-inflammatory cytokine5 and a powerful inhibitor of gastric acid secretion6,7. Host genetic factors that affect interleukin-1-beta may determine why some individuals infected with H. pylori develop gastric cancer while others do not

The stress of starvation: glucocorticoid restraint of beta cell development

Developmental insults during gestation, such as under-nutrition, are known to restrict the number of beta cells that form in the fetal pancreas and are maintained in adulthood, leading to increased risk of type 2 diabetes. There are now substantial data indicating that glucocorticoids mediate this effect of under-nutrition on beta cell mass and that even at physiological levels they restrain fetal beta cell development in utero. There are emerging clues that this occurs downstream of endocrine commitment by neurogenin 3 but prior to terminal beta cell differentiation. Deciphering the precise mechanism will be important as it might unveil new pathways by which to manipulate beta cell mass that could be exploited as novel therapies for patients with diabetes

CD98hc facilitates B cell proliferation and adaptive humoral immunity.

The proliferation of antigen-specific lymphocytes and resulting clonal expansion are essential for adaptive immunity. We report here that B cell-specific deletion of the heavy chain of CD98 (CD98hc) resulted in lower antibody responses due to total suppression of B cell proliferation and subsequent plasma cell formation. Deletion of CD98hc did not impair early B cell activation but did inhibit later activation of the mitogen-activated protein kinase Erk1/2 and downregulation of the cell cycle inhibitor p27. Reconstitution of CD98hc-deficient B cells with CD98hc mutants showed that the integrin-binding domain of CD98hc was required for B cell proliferation but that the amino acid-transport function of CD98hc was dispensable for this. Thus, CD98hc supports integrin-dependent rapid proliferation of B cells. We propose that the advantage of adaptive immunity favored the appearance of CD98hc in vertebrates