Electric Signaling and Pin2 Gene Expression on Different Abiotic Stimuli Depend on a Distinct Threshold Level of Endogenous Abscisic Acid in Several Abscisic Acid-Deficient Tomato Mutants1

Experiments were performed on three abscisic acid (ABA)-deficient tomato (Lycopersicon esculentum Mill.) mutants, notabilis, flacca, and sitiens, to investigate the role of ABA and jasmonic acid (JA) in the generation of electrical signals and Pin2 (proteinase inhibitor II) gene expression. We selected these mutants because they contain different levels of endogenous ABA. ABA levels in the mutant sitiens were reduced to 8% of the wild type, in notabilis they were reduced to 47%, and in flacca they were reduced to 21%. In wild-type and notabilis tomato plants the induction of Pin2 gene expression could be elicited by heat treatment, current application, or mechanical wounding. In flacca and sitiens only heat stimulation induced Pin2 gene expression. JA levels in flacca and sitiens plants also accumulated strongly upon heat stimulation but not upon mechanical wounding or current application. Characteristic electrical signals evolved in the wild type and in the notabilis and flacca mutants consisting of a fast action potential and a slow variation potential. However, in sitiens only heat evoked electrical signals; mechanical wounding and current application did not change the membrane potential. In addition, exogenous application of ABA to wild-type tomato plants induced transient changes in membrane potentials, indicating the involvement of ABA in the generation of electrical signals. Our data strongly suggest the presence of a minimum threshold value of ABA within the plant that is essential for the early events in electrical signaling and mediation of Pin2 gene expression upon wounding. In contrast, heat-induced Pin2 gene expression and membrane potential changes were not dependent on the ABA level but, rather, on the accumulation of JA.

Molecular dynamics of a grid-mounted molecular dipolar rotor in a rotating electric field

Classical molecular dynamics is applied to the rotation of a dipolar molecular rotor mounted on a square grid and driven by rotating electric field E(ν) at T ≃ 150 K. The rotor is a complex of Re with two substituted o-phenanthrolines, one positively and one negatively charged, attached to an axial position of Rh\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} \begin{equation*}{\mathrm{_{2}^{4+}}}\end{equation*}\end{document} in a [2]staffanedicarboxylate grid through 2-(3-cyanobicyclo[1.1.1]pent-1-yl)malonic dialdehyde. Four regimes are characterized by a, the average lag per turn: (i) synchronous (a < 1/e) at E(ν) = |E(ν)| > Ec(ν) [Ec(ν) is the critical field strength], (ii) asynchronous (1/e < a < 1) at Ec(ν) > E(ν) > Ebo(ν) > kT/μ, [Ebo(ν) is the break-off field strength], (iii) random driven (a ≃ 1) at Ebo(ν) > E(ν) > kT/μ, and (iv) random thermal (a ≃ 1) at kT/μ > E(ν). A fifth regime, (v) strongly hindered, W > kT, Eμ, (W is the rotational barrier), has not been examined. We find Ebo(ν)/kVcm−1 ≃ (kT/μ)/kVcm−1 + 0.13(ν/GHz)1.9 and Ec(ν)/kVcm−1 ≃ (2.3kT/μ)/kVcm−1 + 0.87(ν/GHz)1.6. For ν > 40 GHz, the rotor behaves as a macroscopic body with a friction constant proportional to frequency, η/eVps ≃ 1.14 ν/THz, and for ν < 20 GHz, it exhibits a uniquely molecular behavior.

The challenge of contracting for technological information

Contracting to provide technological information (TI) is a significant challenge. TI is an unusual commodity in five ways. (i) TI is difficult to count and value; conventional indicators, such as patents and citations, hardly indicate value. TI is often sold at different prices to different parties. (ii) To value TI, it may be necessary to “give away the secret.” This danger, despite nondisclosure agreements, inhibits efforts to market TI. (iii) To prove its value, TI is often bundled into complete products, such as a computer chip or pharmaceutical product. Efficient exchange, by contrast, would involve merely the raw information. (iv) Sellers’ superior knowledge about TI’s value make buyers wary of overpaying. (v) Inefficient contracts are often designed to secure rents from TI. For example, licensing agreements charge more than marginal cost. These contracting difficulties affect the way TI is produced, encouraging self-reliance. This should be an advantage to large firms. However, small research and development firms spend more per employee than large firms, and nonprofit universities are major producers. Networks of organizational relationships, particularly between universities and industry, are critical in transmitting TI. Implicit barter—money for guidance—is common. Property rights for TI are hard to establish. Patents, quite suitable for better mousetraps, are inadequate for an era when we design better mice. Much TI is not patented, and what is patented sets fuzzy demarcations. New organizational forms are a promising approach to contracting difficulties for TI. Webs of relationships, formal and informal, involving universities, start-up firms, corporate giants, and venture capitalists play a major role in facilitating the production and spread of TI.

Electric-field-induced Schiff-base deprotonation in D85N mutant bacteriorhodopsin.

The application of an external electric field to dry films of Asp-85-->Asn mutant bacteriorhodopsin causes deprotonation of the Schiff base, resulting in a shift of the optical absorption maximum from 600 nm to 400 nm. This is in marked contrast to the case of wild-type bacteriorhodopsin films, in which electric fields produce a red-shifted product whose optical properties are similar to those of the acid-blue form of the protein. This difference is due to the much weaker binding of the Schiff-base proton in the mutant protein, as indicated by its low pK of approximately 9, as compared with the value pK approximately 13 in the wild type. Other bacteriorhodopsins with lowered Schiff-base pK values should also exhibit a field-induced shift in the protonation equilibrium of the Schiff base. We propose mechanisms to account for these observations.

Membrane healing and restoration of contractility after mechanical injury in isolated skeletal muscle fibers of the frog.

In single isolated skeletal muscle fibers of the frog, we studied (i) the recovery from large sarcolemmal mechanical injuries of the response to electric stimulation and (ii) the integrity of the sarcolemma under the light microscope. In Ringer's solution, the damaged cells stopped contracting and deteriorated completely within 1 hr. In the presence of phosphatidylcholine (0.025 g/ml in Ringer's solution), the injured cells initially responded with local twitches. Within 0.5 hr, contractility and membrane integrity started to recover and both were back to control levels within 3 hr. When these cells were placed back in normal Ringer's solution, they remained viable and active for several hours. Our results suggest that phosphatidylcholine can protect muscle fibers from the effects of sarcolemmal injury.

Rectification and signal averaging of weak electric fields by biological cells.

Oscillating electric fields can be rectified by proteins in cell membranes to give rise to a dc transport of a substance across the membrane or a net conversion of a substrate to a product. This provides a basis for signal averaging and may be important for understanding the effects of weak extremely low frequency (ELF) electric fields on cellular systems. We consider the limits imposed by thermal and "excess" biological noise on the magnitude and exposure duration of such electric field-induced membrane activity. Under certain circumstances, the excess noise leads to an increase in the signal-to-noise ratio in a manner similar to processes labeled "stochastic resonance." Numerical results indicate that it is difficult to reconcile biological effects with low field strengths.

Effects of the environment on the electric conductivity of double-stranded DNA molecules

We present a theoretical analysis of the effects of the environment on charge transport in double-stranded synthetic poly(G)-poly(C) DNA molecules attached to two ideal leads. Coupling of the DNA to the environment results in two effects: (i) localization of carrier functions due to static disorder and (ii) phonon-induced scattering of the carriers between the localized states, resulting in hopping conductivity. A nonlinear Pauli master equation for populations of localized states is used to describe the hopping transport and calculate the electric current as a function of the applied bias. We demonstrate that, although the electronic gap in the density of states shrinks as the disorder increases, the voltage gap in the I-V characteristics becomes wider. A simple physical explanation of this effect is provided.

Risco de mercado na comercialização de energia elétrica: uma análise estruturada com foco no ambiente de contratação livre - ACL.

A motivação para o desenvolvimento desse trabalho surge em um momento em que se verifica uma participação cada vez mais significativa das fontes energéticas renováveis não convencionais no País. Não obstante, o cenário de evolução evidencia que o arcabouço regulatório e as regras de mercado não acompanharam as especificidades inerentes à exploração dessas fontes. Assim, para que se mantenha adequado ritmo de inserção na matriz energética, devem ser buscadas opções para que fontes alternativas sejam cada vez mais competitivas na atual configuração do mercado energético. A contribuição dessa pesquisa, portanto, centra-se na análise dos riscos de mercado incorridos por esses geradores de fontes intermitentes de energia ao comercializarem energia no ambiente de contratação livre. Nessa perspectiva, a Dissertação foi desenvolvida abordando tipos de geração de energia e suas características técnicas e econômicas, legislação do setor elétrico, regras de comercialização, balanço energético do sistema, formação de preços no mercado de curto prazo e precificação de contratos no ACL, diferença de preços entre submercados, requisitos de flexibilidade e sazonalidade nos contratos de venda a consumidores livres e seu impacto na precificação de contratos, identificação de comportamento energético complementar para mitigação de riscos de mercado entre fontes renováveis e rebatimento na formulação de mecanismo de hedge, análise de portfólio de contratos e estratégia ótima de contratação de energia para agentes geradores atuando no ACL. Como resposta ao desafio de equacionar o impasse surgido na comercialização de fontes de produção sazonal, propõe-se um modelo para definir estratégias de contratação para agentes geradores e comercializadores a partir da complementação energética entre diferentes tipos de fontes, de forma a maximizar os ganhos de comercialização para um risco estabelecido. Busca-se a composição ideal dessas fontes na carteira de um comercializador para minimizar o risco de exposição à volatilidade dos preços do mercado de curto prazo. Isso é possível em virtude das compensações energéticas feitas entre as diferentes fontes em um portfólio combinado, mitigando a receita em risco decorrente das variações que existem nos preços de curto prazo e na produção energética. De forma complementar, estruturou-se um modelo de negócio no qual uma empresa detentora de ativos de geração hidrelétrica compra os direitos de produção de uma eólica e/ou biomassa para incorporar ao seu portfólio e vender como contrato por quantidade. Determinou-se o volume de energia a ser comprado de cada fonte, o preço, a estratégia mais indicada de contratação e a mitigação de fatores de risco contemplados nos contratos de venda, buscando maximizar os ganhos de comercialização condicionada a critérios de risco pré-fixados.

Comprehensive Greenhouse Gas Management for the Electric Generating Industry

Climate change is becoming more visible in the political arena. Electric generating companies will likely be impacted by future regulation of climate change related emissions. Even though few climate related programs are mandatory, electric generating companies should begin to implement greenhouse gas management systems. This report includes a review of issues facing the electric generating industry, an examination of current emission management programs, and recommendations for an effective greenhouse gas management framework. An effective greenhouse gas management program allows a company to continually improve their impact on climate change by reducing emissions using the plan, do, check, act process. To ease the reporting burden, companies should apply de minimis exemptions to sources that produce less than 5% of emissions.

Opportunities and Challenges for the Widespread Implementation of Battery Powered Electric Transit Buses

The need for more sustainable public transportation choices drives innovation and provides opportunity for improvement in options. Transit buses provide many advantages for efficient transportation and electric drive vehicles are anticipated to play an increasing role in future transportation systems. A lifecycle cost analysis of battery electric transit buses indicates rate structures and demand charges do not currently have a large impact on lifecycle cost for small fleets of battery electric buses. As fleets grow, policies and rate structures will need to adjust to avoid becoming a barrier to adoption. Battery electric transit buses are now being developed which promise to address the primary issues of high life cycle cost, low reliability, range, and flexibility.

Effect of the metal in the production of pollutants during the decomposition of two types of electric wires

Support for this work was provided by the Generalitat Valenciana (Spain) with projects PROMETEO/2009/043/FEDER, and by the Spanish MCT CTQ2008-05520.

Crystallographic orientation and electrode nature are key factors for electric current generation by Geobacter sulfurreducens

We have investigated the influence of electrode material and crystallographic structure on electron transfer and biofilm formation of Geobacter sulfurreducens. Single-crystal gold - Au(110), Au(111), Au(210) - and platinum - Pt(100), Pt(110), Pt(111), Pt(210) - electrodes were tested and compared to graphite rods. G. sulfurreducens electrochemically interacts with all these materials with different attachment kinetics and final current production, although redox species involved in the electron transfer to the anode are virtually the same in all cases. Initial bacterial colonization was fastest on graphite up to the monolayer level, whereas gold electrodes led to higher final current densities. Crystal geometry showed to have an important influence, with Au(210) sustaining a current density of up to 1442 (± 101) μA cm- 2 at the steady state, over Au(111) with 961 (± 94) μA cm- 2 and Au(110) with 944 (± 89) μA cm- 2. On the other hand, the platinum electrodes displayed the lowest performances, including Pt(210). Our results indicate that both crystal geometry and electrode material are key parameters for the efficient interaction of bacteria with the substrate and should be considered for the design of novel materials and microbial devices to optimize energy production.

Decomposition of two types of electric wires considering the effect of the metal in the production of pollutants

Combustion runs at 700 °C in a horizontal laboratory furnace were carried out on two different electric wires (PVC and halogen-free wire). Tests were performed in the presence and in the absence of the metal conductor of the wires. The analyses of the polycyclic aromatic hydrocarbons (PAHs), chlorobenzenes (CBzs), chlorophenols (CPhs), mono- to octa-chlorodibenzo-p-dioxin and dibenzofurans (PCDD/Fs), and dioxin-like PCBs are shown. Regarding semivolatile compounds, PAHs production decreases in the presence of metal, while a higher amount of chlorinated compounds are emitted. Respect to the PCDD/Fs, the PVC wire in the presence of metal presents the highest emission, with a much more emission of furans than dioxins. The maximum emission is with 2 or 3 chlorine atom PCDD/Fs. PCBs emission correlates with PCDD/F production and represents 3–4% of total toxicity, determined by using WHO2005 factors.

BIDIRECTIONAL AC-DC CONVERTERS USING ONE CYCLE CONTROL (OCC) FOR ELECTRIC VEHICLES

The electric vehicle (EV) market has seen a rapid growth in the recent past. With an increase in the number of electric vehicles on road, there is an increase in the number of high capacity battery banks interfacing the grid. The battery bank of an EV, besides being the fuel tank, is also a huge energy storage unit. Presently, it is used only when the vehicle is being driven and remains idle for rest of the time, rendering it underutilized. Whereas on the other hand, there is a need of large energy storage units in the grid to filter out the fluctuations of supply and demand during a day. EVs can help bridge this gap. The EV battery bank can be used to store the excess energy from the grid to vehicle (G2V) or supply stored energy from the vehicle to grid (V2G ), when required. To let power flow happen, in both directions, a bidirectional AC-DC converter is required. This thesis concentrates on the bidirectional AC-DC converters which have a control on power flow in all four quadrants for the application of EV battery interfacing with the grid. This thesis presents a bidirectional interleaved full bridge converter topology. This helps in increasing the power processing and current handling capability of the converter which makes it suitable for the purpose of EVs. Further, the benefit of using the interleaved topology is that it increases the power density of the converter. This ensures optimization of space usage with the same power handling capacity. The proposed interleaved converter consists of two full bridges. The corresponding gate pulses of each switch, in one cell, are phase shifted by 180 degrees from those of the other cell. The proposed converter control is based on the one-cycle controller. To meet the challenge of new requirements of reactive power handling capabilities for grid connected converters, posed by the utilities, the controller is modified to make it suitable to process the reactive power. A fictitious current derived from the grid voltage is introduced in the controller, which controls the converter performance. The current references are generated using the second order generalized integrators (SOGI) and phase locked loop (PLL). A digital implementation of the proposed control ii scheme is developed and implemented using DSP hardware. The simulated and experimental results, based on the converter topology and control technique discussed here, are presented to show the performance of the proposed theory.