Energy in Living Systems

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I NTERNATIONAL J OURNAL OF E NERGY AND E NVIRONMENT Volume 3, Issue 6, 2012 pp.833-860 Journal homepage: www.IJEE.IEEFoundation.org ISSN 2076-2895 (Print), ISSN 2076-2909 (Online) ©2012 International Energy & Environment Foundation. All rights reserved. Water and energy sustainable management in irrigation systems network Kaloyan N. Kenov, Helena M. Ramos Civil Engineering Department and CEHIDRO, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001, Lisbon, Portugal. Abstract Water scarcity, water quality deterioration and the increasing demand for water and for renewable energy in water systems, require sound planning and management practices supported by computer modeling. Such management practices must ensure the sustainable use of water resources, including the achievement of a good status of water bodies as prescribed by the EU Water Framework Directive. The purpose of this paper is to establish the applicability and limitations of two commercial software products to simulate the operation of a water system based on the Sorraia water project in Portugal. Particular attention was given to two products: (1) AQUATOOL, developed by the Universidad Politécnica de Valencia (UPV); and, (2) WEAP developed by the Stockholm Environment Institute (SEI). The capabilities of the two models were analyzed focusing on the following aspects: (1) capability to reproduce the operation of a water system; (2) capacity to estimate the system’s reliability to meet water demands; (3) easiness of the modeling process, including entry data requirements and presentation of results; (4) usefulness to support decisions of water authorities. From the modeling activity process it is possible to conclude that: (1) AQUATOOL and WEAP are applicable in planning exercises, for which it is necessary to evaluate possible modifications in existing water systems and to analyze the effectiveness of resource exploitation policies, by taking into account objectives and infrastructure; and, (2) within certain modeling limitations, these software products can be used for water allocation predictions, multi-reservoir modeling, and reliability assessment of water systems. Copyright © 2012 International Energy and Environment Foundation - All rights reserved. Keywords: Water and energy; Irrigation system; Sustainable management; AQUATOOL; WEAP. 1. Introduction Water is a finite natural resource, which needs sound and sustainable management practices to meet various demands, e.g. water consumption, irrigation, energy production, tourism, fisheries. Computer- supported assessment of water management practices and renewable energy production are important for the sustainable use of water. This is needed to ensure sufficient supply and quality of surface and ground waters as prescribed in the EU Water framework directive (WFD) (2000/60/CE) and in the Portuguese Water Act (Lei no. 58/2005). Climate change has a direct impact on the availability, timing and variability of water supply. This puts an additional pressure on water systems and highlights the need for sound and sustainable management International Journal of Energy and Environment (IJEE), Volume 3, Issue 6, 2012, pp.833-860 ISSN 2076-2895 (Print), ISSN 2076-2909 (Online) ©2012 International Energy & Environment Foundation. All rights reserved. 834 practices. Adding to these direct impacts, there are the indirect impacts, Energy in Living Systems Energy in Living Systems Bởi: OpenStaxCollege Energy production within a cell involves many coordinated chemical pathways Most of these pathways are combinations of oxidation and reduction reactions Oxidation and reduction occur in tandem An oxidation reaction strips an electron from an atom in a compound, and the addition of this electron to another compound is a reduction reaction Because oxidation and reduction usually occur together, these pairs of reactions are called oxidation reduction reactions, or redox reactions Electrons and Energy The removal of an electron from a molecule, oxidizing it, results in a decrease in potential energy in the oxidized compound The electron (sometimes as part of a hydrogen atom), does not remain unbonded, however, in the cytoplasm of a cell Rather, the electron is shifted to a second compound, reducing the second compound The shift of an electron from one compound to another removes some potential energy from the first compound (the oxidized compound) and increases the potential energy of the second compound (the reduced compound) The transfer of electrons between molecules is important because most of the energy stored in atoms and used to fuel cell functions is in the form of high-energy electrons The transfer of energy in the form of electrons allows the cell to transfer and use energy in an incremental fashion—in small packages rather than in a single, destructive burst This chapter focuses on the extraction of energy from food; you will see that as you track the path of the transfers, you are tracking the path of electrons moving through metabolic pathways Electron Carriers In living systems, a small class of compounds functions as electron shuttles: They bind and carry high-energy electrons between compounds in pathways The principal electron carriers we will consider are derived from the B vitamin group and are derivatives of nucleotides These compounds can be easily reduced (that is, they accept electrons) or oxidized (they lose electrons) Nicotinamide adenine dinucleotide (NAD) ([link]) is derived from vitamin B3, niacin NAD+ is the oxidized form of the molecule; NADH is the reduced form of the molecule after it has accepted two electrons and a proton (which together are the equivalent of a hydrogen atom with an extra electron) 1/7 Energy in Living Systems NAD+ can accept electrons from an organic molecule according to the general equation: NAD + RH Reducing agent + Oxidizing agent → NADH Reduced + R Oxidized When electrons are added to a compound, they are reduced A compound that reduces another is called a reducing agent In the above equation, RH is a reducing agent, and NAD+ is reduced to NADH When electrons are removed from compound, it oxidized A compound that oxidizes another is called an oxidizing agent In the above equation, NAD+ is an oxidizing agent, and RH is oxidized to R Similarly, flavin adenine dinucleotide (FAD+) is derived from vitamin B2, also called riboflavin Its reduced form is FADH2 A second variation of NAD, NADP, contains an extra phosphate group Both NAD+ and FAD+ are extensively used in energy extraction from sugars, and NADP plays an important role in anabolic reactions and photosynthesis The oxidized form of the electron carrier (NAD+) is shown on the left and the reduced form (NADH) is shown on the right The nitrogenous base in NADH has one more hydrogen ion and two more electrons than in NAD+ 2/7 Energy in Living Systems ATP in Living Systems A living cell cannot store significant amounts of free energy Excess free energy would result in an increase of heat in the cell, which would result in excessive thermal motion that could damage and then destroy the cell Rather, a cell must be able to handle that energy in a way that enables the cell to store energy safely and release it for use only as needed Living cells accomplish this by using the compound adenosine triphosphate (ATP) ATP is often called the “energy currency” of the cell, and, like currency, this versatile compound can be used to fill any energy need of the cell How? It functions similarly to a rechargeable battery When ATP is broken down, usually by the removal of its terminal phosphate group, energy is released The energy is used to work by the cell, usually by the released phosphate binding to another molecule, activating it For example, in the mechanical work of muscle contraction, ATP supplies the energy to move the contractile muscle proteins Recall the active transport work of the sodium-potassium pump in cell membranes ATP alters the structure of the integral protein that functions as the pump, changing its affinity for sodium and potassium In this way, the cell performs work, pumping ions against their electrochemical gradients ATP Structure and Function At the heart of ATP is a molecule of adenosine monophosphate (AMP), which is composed of an adenine molecule bonded to a ribose molecule and to a single phosphate group ([link]) Ribose is ... I NTERNATIONAL J OURNAL OF E NERGY AND E NVIRONMENT Volume 3, Issue 4, 2012 pp.521-530 Journal homepage: www.IJEE.IEEFoundation.org ISSN 2076-2895 (Print), ISSN 2076-2909 (Online) ©2012 International Energy & Environment Foundation. All rights reserved. Integration of energy and environmental systems in wastewater treatment plants Suzanna Long 1 , Elizabeth Cudney 2 1 Department of Engineering Management and Systems Engineering, 600 W, 14 th Street, 215 EMGT Building, Rolla, MO-65401, 573-341-7621, U.S.A. 2 Department of Engineering Management and Systems Engineering, 600 W, 14 th Street, 217 EMGT Building, Rolla, MO-65401, 573-341-7931, U.S.A. Abstract Most wastewater treatment facilities were built when energy costs were not a concern; however, increasing energy demand, changing climatic conditions, and constrained energy supplies have resulted in the need to apply more energy-conscious choices in the maintenance or upgrade of existing wastewater treatment facilities. This research develops an integrated energy and environmental management systems model that creates a holistic view of both approaches and maps linkages capable of meeting high-performing energy management while meeting environmental standards. The model has been validated through a case study on the Rolla, Missouri Southeast Wastewater Treatment Plant. Results from plant performance data provide guidance to improve operational techniques. The significant factors contributing to both energy and environmental systems are identified and balanced against considerations of cost. Copyright © 2012 International Energy and Environment Foundation - All rights reserved. Keywords: Energy conservation; Environmental management; Process integration; Strategic management; Wastewater treatment systems. 1. Introduction Green environmental practices are increasingly important in combating serious global energy and environmental issues. Water and wastewater facilities are among the largest and most energy-intensive systems owned and operated by local governments and account for approximately 30 to 50% of municipal energy use. Most wastewater treatment facilities were built when energy costs were not a concern; however, increasing energy demand, changing climatic conditions, and constrained energy supplies have resulted in the need to apply more energy-conscious choices in the maintenance or upgrade of existing wastewater treatment facilities. Energy represents the largest controllable cost of water and wastewater treatment since energy use directly affects the amount of greenhouse gas (GHG) emissions, and indirectly affects the biological oxygen demand (BOD), chemical oxygen demand (COD), and pollutions levels. By controlling the level of energy consumption, wastewater treatment facilities can reduce the operating costs, increase efficiency, and reduce pollution in an effort to provide cleaner environments. In addition, increased training on advanced equipment by well-trained employees can lead to improved effluent and surface water quality and more compliant facilities [1, 2]. A strategic process to control these various factors could provide significant benefits to local governments and the communities they serve. International Journal of Energy and Environment (IJEE), Volume 3, Issue 4, Loose interaction between glyceraldehyde-3-phosphate dehydrogenase and phosphoglycerate kinase revealed by fluorescence resonance energy transfer–fluorescence lifetime imaging microscopy in living cells Yosuke Tomokuni 1 , Kenji Goryo 1 , Ayako Katsura 1 , Satoru Torii 1 , Ken-ichi Yasumoto 1 , Klaus Kemnitz 2 , Mamiko Takada 3 , Hiroshi Fukumura 3 and Kazuhiro Sogawa 1 1 Department of Biomolecular Sciences, Graduate School of Life Sciences, Tohoku University, Aoba-ku Sendai, Japan 2 EuroPhoton GmbH, Berlin, Germany 3 Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku Sendai, Japan Introduction It has been demonstrated that consecutive enzymes in a number of metabolic pathways may form readily dis- sociable enzyme–enzyme complexes by which interme- diary metabolites are directly transferred from one enzyme to the next without being released into the aqueous environment [1,2]. In the glycolytic and glu- coneogenic pathways, pairs of enzymes – aldolase and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), GAPDH and phosphoglycerate kinase (PGK), GAP- DH and lactate dehydrogenase, and aldolase and fruc- tose-1,6-bisphosphatase – are reported to form loose complexes [1,2]. Of these enzyme pairs, GAPDH and PGK constitute the sixth and seventh reactions in the glycolytic pathway. GAPDH is a homotetramer with a Keywords FLIM; FRET; GAPDH; loose interaction; PGK Correspondence K. Sogawa, Department of Biomolecular Sciences, Graduate School of Life Sciences, Tohoku University, Aoba-ku Sendai 980-8578, Japan Fax: +81 22 795 6594 Tel: +81 22 795 6590 E-mail: sogawa@mail.tains.tohoku.ac.jp (Received 14 April 2009, revised 7 December 2009, accepted 24 December 2009) doi:10.1111/j.1742-4658.2010.07561.x Loose interaction between the glycolytic enzymes glyceraldehyde-3-phos- phate dehydrogenase (GAPDH) and phosphoglycerate kinase (PGK) was visualized in living CHO-K1 cells by fluorescence resonance energy transfer (FRET), using time-domain fluorescence lifetime imaging microscopy. FRET between active tetrameric subunits of GAPDH linked to cerulean or citrine was observed, and this FRET signal was significantly attenuated by coexpression of PGK. Also, direct interaction between GAPDH–citrine and PGK–cerulean was observed by FRET. The strength of FRET signals between them was dependent on linkers that connect GAPDH to citrine and PGK to cerulean. A coimmunoprecipitation assay using hemaggluti- nin-tagged GAPDH and FLAG-tagged PGK coexpressed in CHO-K1 cells supported the FRET observation. Taken together, these results demon- strate that a complex of GAPDH and PGK is formed in the cytoplasm of living cells. Structured digital abstract l MINT-7386555: PGK (uniprotkb:P00558) physically interacts (MI:0915) with GAPDH (uni- protkb: P04406)byanti tag coimmunoprecipitation (MI:0007) l MINT-7386573: GAPDH (uniprotkb:P04406) and PGK (uniprotkb:P00558) bind (MI:0407) by fluorescent resonance energy transfer ( MI:0055) l MINT-7386590: GAPDH (uniprotkb:P04406) and GAPDH (uniprotkb:P04406) bind ( MI:0407)byfluorescent resonance energy transfer (MI:0055) Abbreviations DAPI, 4¢,6-diamidino-2-phenylindole; FLIM, fluorescence lifetime imaging microscopy; FRET, fluorescence resonance energy transfer; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; GFP, green fluorescent protein; HA, hemagglutinin; IRF, instrumental response function; PGK, phosphoglycerate kinase; TRITC, tetramethylrhodamine isothiocyanate. 1310 FEBS Journal 277 (2010) 1310–1318 ª 2010 The Authors Journal compilation ª 2010 Ternary complex formation of pVHL, elongin B and elongin C visualized in living cells by a fluorescence resonance energy transfer–fluorescence lifetime imaging microscopy technique Koshi Kinoshita 1, *, Kenji Goryo 1, *, Mamiko Takada 2 , Yosuke Tomokuni 1 , Teijiro Aso 3 , Heiwa Okuda 4 , Taro Shuin 4 , Hiroshi Fukumura 2 and Kazuhiro Sogawa 1 1 Department of Biomolecular Sciences, Graduate School of Life Sciences, Tohoku University, Aoba-ku Sendai, Japan 2 Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku Sendai, Japan 3 Department of Functional Genomics, Kochi Medical School, Kohasu, Okoh-cho, Nankoku Kochi, Japan 4 Department of Urology, Kochi Medical School, Kohasu, Okoh-cho, Nankoku Kochi, Japan The von Hippel–Lindau (VHL) gene is located on the short arm of chromosome 3 and its deletions or muta- tions are associated with VHL disease [1,2]. Affected individuals develop a variety of tumors, including retinal hemangioblastomas, hemangioblastomas of the central nervous system, renal cell carcinomas and pheochromocytomas. Biallelic VHL gene defects are also found in sporadic malignancies, such as renal cell carcinomas and hemangioblastomas [3,4]. The VHL gene product exists in two forms, a larger p30 protein (pVHL30) and a smaller p19 protein (pVHL19), the latter generated by internal translation initiation at the Keywords conformation change; FRET–FLIM; live cell imaging; protein complex; ubiquitin ligase Correspondence K. Sogawa, Department of Biomolecular Science, Graduate School of Life Sciences, Tohoku University, Aoba-ku Sendai 980-8578 Japan Fax: +81 22 795 6594 Tel: +81 22 795 6590 E-mail: sogawa@mail.tains.tohoku.ac.jp *These authors contributed equally to this work (Received 26 June 2007, revised 21 August 2007, accepted 29 August 2007) doi:10.1111/j.1742-4658.2007.06075.x The tumor suppressor von Hippel–Lindau (VHL) gene product forms a com- plex with elongin B and elongin C, and acts as a recognition subunit of a ubiquitin E3 ligase. Interactions between components in the complex were investigated in living cells by fluorescence resonance energy transfer (FRET)–fluorescence lifetime imaging microscopy (FLIM). Elongin B–ceru- lean or cerulean–elongin B was coexpressed with elongin C-citrine or citrine- elongin C in CHO-K1 cells. FRET signals were examined by measuring a change in the fluorescence lifetime of donors and by monitoring a corre- sponding fluorescence rise of acceptors. Clear FRET signals between elon- gin B and elongin C were observed in all combinations, except for the combination of elongin B-cerulean and citrine-elongin C. Although similar experiments to examine interaction between pVHL30 and elongin C linked to cerulean or citrine were performed, FRET signals were rarely observed among all the combinations. However, the signal was greatly increased by coexpression of elongin B. These results, together with results of coimmuno- precipitation experiment using pVHL, elongin C and elongin B, suggest that a conformational change of elongin C and ⁄ or pVHL was induced by binding of elongin B. The conformational change of elongin C was investigated by measuring changes in the intramolecular FRET signal of elongin C linked to cerulean and citrine at its N- STATISTICS OF ENERGY LEVELS AND EIGENFUNCTIONS IN DISORDERED SYSTEMS Alexander D. MIRLIN Institut fu( r Theorie der kondensierten Materie, Universita( t Karlsruhe, 76128 Karlsruhe, Germany AMSTERDAM } LAUSANNE } NEW YORK } OXFORD } SHANNON } TOKYO A.D. Mirlin / Physics Reports 326 (2000) 259} 382 259  Tel.: #49-721-6083368; fax: #49-721-698150. Also at Petersburg Nuclear Physics Institute, 188350 Gatchina, St. Petersburg, Russia. E-mail address: mirlin@tkm.physik.uni-karlsruhe.de (A.D. Mirlin) Physics Reports 326 (2000) 259}382 Statistics of energy levels and eigenfunctions in disordered systems Alexander D. Mirlin  Institut fu( r Theorie der kondensierten Materie, Postfach 6980, Universita( t Karlsruhe, 76128 Karlsruhe, Germany Received July 1999; editor: C.W.J. Beenakker Contents 1. Introduction 262 2. Energy level statistics: random matrix theory and beyond 266 2.1. Supersymmetric -model formalism 266 2.2. Deviations from universality 269 3. Statistics of eigenfunctions 273 3.1. Eigenfunction statistics in terms of the supersymmetric -model 273 3.2. Quasi-one-dimensional geometry 277 3.3. Arbitrary dimensionality: metallic regime 283 4. Asymptotic behavior of distribution functions and anomalously localized states 294 4.1. Long-time relaxation 294 4.2. Distribution of eigenfunction amplitudes 303 4.3. Distribution of local density of states 309 4.4. Distribution of inverse participation ratio 312 4.5. 3D systems 317 4.6. Discussion 319 5. Statistics of energy levels and eigenfunctions at the Anderson transition 320 5.1. Level statistics. Level number variance 320 5.2. Strong correlations of eigenfunctions near the Anderson transition 325 5.3. Power-law random banded matrix ensemble: Anderson transition in 1D 328 6. Conductance #uctuations in quasi-one- dimensional wires 344 6.1. Modeling a disordered wire and mapping onto 1D -model 345 6.2. Conductance #uctuations 348 7. Statistics of wave intensity in optics 353 8. Statistics of energy levels and eigenfunctions in a ballistic system with surface scattering 360 8.1. Level statistics, low frequencies 362 8.2. Level statistics, high frequencies 363 8.3. The level number variance 364 8.4. Eigenfunction statistics 365 9. Electron}electron interaction in disordered mesoscopic systems 366 9.1. Coulomb blockade: #uctuations in the addition spectra of quantum dots 367 10. Summary and outlook 373 Acknowledgements 374 Appendix A. Abbreviations 374 References 375 0370-1573/00/$ - see front matter  2000 Elsevier Science B.V. All rights reserved. PII: S 0 3 7 0 - 1 573(99)00091-5 Abstract The article reviews recent developments in the theory of #uctuations and correlations of energy levels and eigenfunction amplitudes in di!usive mesoscopic samples. Various spatial geometries are considered, with emphasis on low-dimensional (quasi-1D and 2D) systems. Calculations are based on the supermatrix -model approach. The method reproduces, in so-called zero-mode approximation, the universal random matrix theory (RMT) results for the energy-level and eigenfunction #uctuations. Going beyond this approxi- mation allows us to study system-speci"c deviations from universality, which are determined by the di!usive classical dynamics in the system. These deviations are especially strong in the far `tailsa of the distribution function of the eigenfunction amplitudes (as well as of some related quantities, such as local density of states, relaxation ... nitrogenous base in NADH has one more hydrogen ion and two more electrons than in NAD+ 2/7 Energy in Living Systems ATP in Living Systems A living cell cannot store significant amounts of free energy Excess... of the involvement of oxygen in the process 5/7 Energy in Living Systems In eukaryotes, oxidative phosphorylation takes place in mitochondria In prokaryotes, this process takes place in the plasma... ADP molecule, reforming ATP Obviously, energy must be infused into the system to regenerate ATP Where does this energy come from? In nearly every living thing on earth, the energy comes from the