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Repeated treatment of rats with ethanol (1 g/kg, once daily for 15 days) enhanced the locomotor effect of morphine, 3 weeks post-treatment. This ethanol-induced long-term behavioural sensitization to morphine was associated with an increase in the electrically evoked release of [3H]dopamine (DA) and [14C]acetylcholine (ACh) from nucleus accumbens slices. A similar enhanced responsiveness of accumbal dopaminergic and cholinergic neurons to depolarization was apparent 3 weeks after repeated morphine, amphetamine or cocaine administration. Prior ethanol exposure also caused a long-term enhancement of electrically evoked release of [3H]DA and [14C]ACh from slices of the caudate-putamen. Unlike the locomotor effect of morphine, that of amphetamine was not enhanced in ethanol-pretreated rats. These data indicate that ethanol administration may cause long-term behavioural sensitization associated with adaptive changes in dopaminergic and cholinergic neurons of rat nucleus accumbens and caudate-putamen. Furthermore, an enhanced reactivity of nucleus accumbens dopaminergic nerve terminals and dopamine-sensitive cholinergic neurons appears to be a common long-term neuroadaptive effect of distinct types of addictive drugs. However, since repeated ethanol exposure did not cause a long-term increase in the locomotor effect of amphetamine, these neuroadaptations may not always be sufficient to cause long-lasting behavioural (cross-)sensitization.

Scientific evidence and evidence-based reasoning are likely to face epistemological challenges when brought into societal debate if their foundational assumptions generate cognitive dissonance among key elements of the community. The risk of dissonance is even greater when scientific demonstrations and models are concerned with the decisions and behaviours of people interacting with an environment of interest. In this case, scientific information is often perceived as distorted or biased due to the inherent uncertainties attached to human ecosystems Human ecosystems are complex and adaptive, largely due to our individual cognitive capacities and communication skills. Complex systems science aims to track uncertainties attached to these systems by exploring metaphoric models of reality.

AbstractThis paper presents a case study on improving the energy integration of a gas‐based ethylene process by focusing on major sources of thermal exergy losses. Exergy analysis is used to find the main sources of thermal exergetic inefficiency. Thermal solutions are then developed, leading to a comprehensive list of cold and hot process streams that could potentially reduce exergy losses from these sources. Pinch analysis is then carried out to screen these streams so only those, which can minimize the energy requirement, are maintained. Besides this, pinch analysis is used to select utilities and to explore cogeneration potential. Thus, the methodology used in this paper takes advantage of both exergy and pinch analyses, in a way that all the possible thermal solutions supported by exergy analysis are considered, preventing exclusion of any hot or cold process stream with high potential for heat integration during pinch analysis.

Coordinate pulsewidth modulation is considered for the control of power switches of matrix and two-component direct frequency converters (DFC) in ac drive systems. The synthesis of modulating signals yielding the specified output voltages and sinusoidal grid currents for converters with no intermediate smoothing filter is discussed. Simulation of DFC operation with an RLE load and an asynchronous motor is undertaken.

A novel high spatial resolution synchrotron X-ray diffraction stratigraphy technique has been applied in-situ to an integrated plasmonic nanoparticle-based organic photovoltaic device. This original approach allows for the disclosure of structure-property relations linking large scale organic devices to length scales of local nano/hetero structures and interfaces between the different components.

Biochars are products that are rich in carbon obtained by pyrolysis processes that consist in introducing a biomass (such as wood or manure) in a closed container and heating it with little or no available air. This paper reports the impacts of pyrolysis parameters on biochar characteristics. A preliminary examination of the scientific literature revealed that the type of feedstock, the temperature, the heating rate and the gas flow were the major parameters influencing the biochar characteristics. This review highlights the multitude of biochars that can be made and shows the importance of characterizing them before their use in soils. Then we assess how the input of biochars in soils can affect soil parameters. A review of the literature showed modifications on: i) the physical properties of soils (i.e. the modification in soil structure and water retention), ii) the chemical properties of soils (i.e. the modification of pH, cation exchange capacity, nutrient availability, the organic matter content) and iii) the biological properties (i.e. the changes in microbial and faunal communities). All these modifications can lead to an increase in crop productivity, which confirms the value of biochars as a soil amendment. Moreover, biochars can also provide an advantage for soil remediation. Indeed, biochars efficiently reduce the bioavailability of organic and inorganic pollutants. In addition, this review focuses on a specific plant that can be used to produce biochars: Miscanthus, a non-wood rhizomatous C4 perennial grass. Miscanthus presents advantages for biochar production due to: i) its lignocellulosic content, ii) its silicon content, which can mitigate environmental stresses (notably for plants grown on contaminated sites) and iii) the greater surface area of the Miscanthus biochars compared to the biochars produced with other feedstock.

The electrochemical behavior of Nb in acid fluoride media has been investigated by voltammetric, steady-state, and impedance techniques as a function of variables like c(F) (the total fluoride concentration, varied between 0 and 2 M!, pH (0-7), and potential (-1 to 7 V vs. SCE). An active/passive transition is observed, followed by a wide current pseudoplateau where current depends on c(F) and pH in a way indicating that HF and related species dissolve the passivating oxide whereas F- is inactive. Impedance diagrams obtained on this plateau can be reproduced by a literature model (surface charge approach), and the derived parameters may be used to calculate structural and kinetic quantities, as well as the formation ratio of the surface oxide.

The forested area in the most inhabited lands of the European Ural part of the Russian Federation is occupied mainly by low-grade hardwood with a predominance of birch and aspen. Pyrolysis is a traditional method for low-grade wood processing; the produced charcoal can be effectively used in the technology of other carbon materials. The structure of the developed system for the production of carbon materials from wood consists of 4 subsystems: 1 - raw material procurement, 2 - primary wood processing, 3 - wood pyrolysis, 4 - charcoal processing. When harvesting and primary processing of wood, energy and resource saving is ensured through the wood waste utilization; during pyrolysis - by using heat exothermic reactions. In the timber industry enterprises, the excess heat abstraction is possible when using modular pyrolysis retort units and similar apparatuses for the production of charcoal. When processing charcoal, resource saving is provided by briquetting of its small fractions, and energy saving - by activation gases burning. Water steam activation poses the least environmental hazard in the producing process of active carbons. We propose to conduct oxidation of activated charcoal (for reasons of environmental safety) in the vapor phase using hot moist air as an oxidizing agent. At the same time, no wastewater is formed. The analysis of options of low-grade wood processing has shown that the developed technology of carbon materials allows us to increase the cost of products, for example, from 1 m(3) of birch wood more than 3 times, and to increase the economic stability of forestry enterprises. At the same time, we can obtain up to 4 types of carbon materials (charcoal, wood-coal briquettes, activated and oxidized coals), and reduce the environmental hazard of their production by burning a steam-gas mixture of wood pyrolysis, by the use of water vapor (at the stage of activated charcoals producing) and air (at the stage of obtaining of oxidized coal). Лесопокрытая площадь в наиболее обжитых районах Европейско-Уральской части Российской Федерации занята в основном низкосортной лиственной древесиной с преобладанием березы и осины. Пиролиз является традиционным способом переработки низкосортной древесины, получаемый при этом древесный уголь может быть эффективно использован в технологии других углеродных материалов. Разработанная нами структура системы получения углеродных материалов из древесины состоит из четырех подсистем: 1 - заготовка сырья, 2 - первичная обработка древесины, 3 - пиролиз древесины, 4 - переработка древесного угля. При заготовке и первичной обработке древесины энерго- и ресурсосбережение обеспечиваются за счет утилизации древесных отходов, при пиролизе - за счет применения тепла экзотермических реакций. Показано, что в условиях лесопромышленных предприятий отбор избыточного тепла возможен при использовании для производства древесного угля модульных пиролизных ретортных установок и подобных им аппаратов. При переработке древесного угля ресурсосбережение обеспечивается за счет направления его мелких фракций на брикетирование, а энергосбережение - при сжигании газов активации. В процессе получения активных углей наименьшую экологическую опасность представляет активация водяным паром. Окисление активного угля (по соображениям экологической безопасности) предлагается проводить в паровой фазе с использованием горячего влажного воздуха в качестве окислителя. При этом не образуется сточных вод. Анализ вариантов переработки низкосортной древесины показал, что разработанная нами технология получения углеродных материалов позволяет более чем в 3 раза увеличить стоимость продукции, производимой, например, из 1 м3 березовой древесины, повысить экономическую стабильность предприятий лесного комплекса,получить до четырех видов углеродных материалов (древесный уголь, древесно-угольные брикеты, активные и окисленные угли), а также снизить экологическую опасность их производства за счет сжигания парогазовой смеси пиролиза древесины, применения водяного пара (на стадии получения активных углей) и воздуха (на стадии получения окисленного угля).

The real impact of true bug damage on cocoa pods has never been assessed precisely. We conducted a 2-yr study on 1,080 cocoa trees on 36 farms in Cameroon to assess the contribution of true bugs to fruit mortality and production loss. The cocoa fruiting cycle, fruit mortality, and damage caused by true bugs as well as other pests and diseases were monitored on a weekly basis. True bug damage also was described on 2,500 ripe pods per year. Pod weight, bean number, and bean weight were measured and compared for different degrees and types of damage on the ripe pods. Our results showed that true bugs were the main external cause of young fruit abortion. They reduced the abundance of young fruit by up to 10%. In contrast, although one-third of the ripe pods sampled had true bug lesions, only 4% were moderately to heavily damaged. The mean weight of ripe pods was reduced by 12% when there was medium to heavy damage. While the mean weight of wet beans was reduced significantly (by 3-10%), the number of beans per pod was not changed by damage. Despite the reduction in mean weight, the overall weight of beans for the pods sampled was reduced by <2%. Therefore, our study confirmed the common assumption that the economic impact of true bug damage on mature pods is negligible on cocoa farms in Cameroon. However, true bugs have a significant impact on young fruit mortality.