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Diversity-biomass studies across (sub-)tropical forest strata have been explored, but our understanding on how multiple facets of forest diversity and abiotic factors regulate aboveground biomass across forest strata in temperate forests remains somehow unclear. Here, we conducted a comprehensive analysis of the effects and relative importance of taxonomic, phylogenetic and functional diversity, community-weighted mean (CWM) of trait values, coefficient of variation in individual tree diameter at breast height (CV DBH), and soil and topographic factors on aboveground biomass to select the diversity facets that could have the strongest response to abiotic factors across over- and understory and whole community in a temperate forest of South Korea. We used forest inventory, functional traits and environmental factors data from 259 plots to select the most important diversity facets with abiotic factors through multi-model inference tests, and we then used structural equation models. In the overstory, the most important regulators of aboveground biomass were topographic factor, species evenness, functional richness, and CV DBH. In the understory, the significant drivers of aboveground biomass were topographic factor, species evenness, phylogenetic species richness and CWM of height. In addition, diversity facets of overstory such as functional richness and CV DBH also had significant direct and/or indirect effects on understory aboveground biomass. Moreover, the diversity facets influencing aboveground biomass at the whole community were the combination of the multiple facets of forest diversity influencing aboveground biomass at each forest stratum. The role of functional dominance (CWM of height) seems to be negligible in the overstory but significant in the understory, indicating different diversity drivers as shown previously for a subtropical forest. Hence, our study suggests the urgent need of exploring diversity-biomass studies across forest strata in different forest ecosystems and types in order to provide more specific guidelines for the management of a specific natural forest.

In this study, we investigated the antiinflammatory effects of ethanol extracts of Potentilla. supina Linne (EPS) in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages and septic mice. EPS suppressed LPS-induced nitric oxide, prostaglandin E2 , TNF-α, interleukin-6 and interleukin-1β at production and mRNA levels in LPS-induced RAW 264.7 macrophages. Consistent with these observations, EPS attenuated the expressions of inducible nitric oxide synthase and cyclooxygenase-2 by downregulation of their promoter activities. Molecularly, EPS reduced the LPS-induced transcriptional activity and DNA-binding activity of nuclear factor-κB (NF-κB), and this was associated with a decrease of translocation and phosphorylation of p65 NF-κB by inhibiting the inhibitory κB-α degradation and IKK-α/β phosphorylation. Furthermore, EPS inhibited the LPS-induced activation of activator protein-1 by reducing the expression of c-Fos and c-Jun in nuclear. EPS also suppressed the phosphorylation of mitogen-activated protein kinase, such as p38 mitogen-activated protein kinase and c-Jun N-terminal kinase. In an LPS-induced endotoxemia mouse model, pretreatment with EPS reduced the mRNA levels of inducible nitric oxide synthase, cyclooxygenase-2 and proinflammatory cytokines and increased the survival rate of mice. Collectively, these results suggest that the antiinflammatory effects of EPS were associated with the suppression of NF-κB and activator protein-1 activation and support its possible therapeutic role for the treatment of endotoxemia. Copyright © 2017 John Wiley & Sons, Ltd.

Diesel engines have proved its utility in transport, agriculture and power sector. Environmental norms and scared fossil fuel have attracted the attention to switch the energy demand to alternative energy source. Oil derived from Jatropha curcas plant has been considered as a sustainable substitute to diesel fuel. However, use of straight vegetable oil has encountered problem due to its high viscosity. The aim of present work is to reduce the viscosity of oil by heating from exhaust gases before fed to the engine, the study of effects of FIT (fuel inlet temperature) on engine performance and emissions using a dual fuel engine test rig with an appropriately designed shell and tube heat exchanger (with exhaust bypass arrangement). Heat exchanger was operated in such a way that it could give desired FIT. Results show that BTE (brake thermal efficiency) of engine was lower and BSEC (brake specific energy consumption) was higher when the engine was fueled with Jatropha oil as compared to diesel fuel. Increase in fuel inlet temperature resulted in increase of BTE and reduction in BSEC. Emissions of NO from Jatropha oil during the experimental range were lower than diesel fuel and it increases with increase in FIT. CO (carbon monoxide), HC (hydrocarbon), CO(2) (carbon dioxide) emissions from Jatropha oil were found higher than diesel fuel. However, with increase in FIT, a downward trend was observed. Thus, by using heat exchanger preheated Jatropha oil can be a good substitute fuel for diesel engine in the near future. Optimal fuel inlet temperature was found to be 80 degrees C considering the BTE, BSEC and gaseous emissions. (C) 2010 Elsevier Ltd. All rights reserved.

Abstract Further advance of glazed, healthy building's energy efficiency and sustainability is inextricable linked to the building's envelopes/facades fundamental physics study related to the dynamic control of sunlight and optimal control of solar heat gains. Relevant mathematical models and algorithms, as well as infrastructure/hardware and software integrated performance prediction and validation are studied. Reviewed is the most recent analytical and experimental research, current state of science and art, as well as some of the on-going R&D at the edge of new breakthroughs of the healthy buildings daylighting dynamic control's performance prediction and validation. It has been shown that, concerning the variability of the solar radiation spectra incident on the building's envelope, and also variability of outdoor and indoor air temperature differences, it is necessary tuning control of glazing's transmittance dependence on the solar radiation wavelength, with an aim to optimize daylighting with the reference to people needs (their health and comfort), and energy (thermal and electrical loads minimization). Finally, presented are elements of an analytical modeling approach, as initial results of study, aimed to reach a challenging research goal – Tuning control of buildings Glazing's transmittance dependence on the solar radiation wavelength to optimize daylighting and building's energy efficiency.

Abstract This study examined an innovative self-heat-recuperation technology that circulates latent and sensible heat in the thermal process and applied it to the NGL (natural gas liquid) recovery process. A CGCC (column grand composite curve) was used to assess the thermodynamic feasibility of implementing the heat pump system and self-heat-recuperation technology into a conventional distillation column. The proposed distillation based on self-heat recuperation reduced the energy consumption dramatically by compressing the effluent stream, whose temperature was increased to provide the minimum temperature difference for the heat exchanger, and circulating the stream heat in the process. According to a simulation of the proposed sequence, up to 73.43 and 83.48% of the condenser and reboiler energy, respectively, were saved compared to a conventional column. This study also proposes heat integration to improve the performance of self-heat recuperation. The results showed that the modified sequence saves up 64.35, 100.00 and 31.60% of the condenser energy requirements, reboiler energy requirements and OP (operating cost), respectively, compared to a classical heat pump system, and 90.24, 100.00, and 67.19%, respectively, compared to a conventional column. The use of these sequences to retrofit a distillation column to save energy was also considered.

Microbial fuel cells (MFCs) are biochemical systems having the benefit of producing green energy through the microbial degradation of organic contaminants in wastewater. The efficiency of MFCs largely depends on the cathode oxygen reduction reaction (ORR). A preferable ORR catalyst must have good oxygen reduction kinetics, high conductivity and durability, together with cost-effectiveness. Platinum-based electrodes are considered a state-of-the-art ORR catalyst. However, the scarcity and higher cost of Pt are the main challenges for the commercialization of MFCs; therefore, in search of alternative, cost-effective catalysts, those such as doped carbons and transition-metal-based electrocatalysts have been researched for more than a decade. Recently, perovskite-oxide-based nanocomposites have emerged as a potential ORR catalyst due to their versatile elemental composition, molecular mechanism and the scope of nanoengineering for further developments. In this article, we discuss various studies conducted and opportunities associated with perovskite-based catalysts for ORR in MFCs. Special focus is given to a basic understanding of the ORR reaction mechanism through oxygen vacancy, modification of its microstructure by introducing alkaline earth metals, electron transfer pathways and the synergistic effect of perovskite and carbon. At the end, we also propose various challenges and prospects to further improve the ORR activity of perovskite-based catalysts.

AbstractConventional acetone–butanol–ethanol (ABE) fermentation is severely limited by low solvent titer and productivities. Thus, this study aims at developing an improved Clostridium acetobutylicum strain possessing enhanced ABE production capability followed by process optimization for high ABE productivity. Random mutagenesis of C. acetobutylicum PJC4BK was performed by screening cells on fluoroacetate plates to isolate a mutant strain, BKM19, which exhibited the total solvent production capability 30.5% higher than the parent strain. The BKM19 produced 32.5 g L−1 of ABE (17.6 g L−1 butanol, 10.5 g L−1 ethanol, and 4.4 g L−1 acetone) from 85.2 g L−1 glucose in batch fermentation. A high cell density continuous ABE fermentation of the BKM19 in membrane cell‐recycle bioreactor was studied and optimized for improved solvent volumetric productivity. Different dilution rates were examined to find the optimal condition giving highest butanol and ABE productivities. The maximum butanol and ABE productivities of 9.6 and 20.0 g L−1 h−1, respectively, could be achieved at the dilution rate of 0.85 h−1. Further cell recycling experiments were carried out with controlled cell‐bleeding at two different bleeding rates. The maximum solvent productivities were obtained when the fermenter was operated at a dilution rate of 0.86 h−1 with the bleeding rate of 0.04 h−1. Under the optimal operational condition, butanol and ABE could be produced with the volumetric productivities of 10.7 and 21.1 g L−1 h−1, and the yields of 0.17 and 0.34 g g−1, respectively. The obtained butanol and ABE volumetric productivities are the highest reported productivities obtained from all known‐processes. Biotechnol. Bioeng. 2013; 110: 1646–1653. © 2013 Wiley Periodicals, Inc.

This paper presents a headlamp model that can be used as part of a computer simulation of a wiring system in a vehicle. As more electrical equipment is installed in a vehicle, the wiring system connecting such equipment becomes more complicated, and thus it is essential to conduct a simulation of the wiring system to confirm its capacity. To perform this simulation requires exact models of the electrical equipment fitted to the vehicle. A headlamp model is especially important since currents flowing in the lamp vary dramatically. In this paper, a headlamp model is developed on the basis of the first law of thermodynamics, which is also applicable to a fog lamp. The headlamp is modelled as a variable resistor whose resistance is determined by the change in the operating temperature on account of the applied voltage. The resistance change was simulated using the model, and the resistance of an actual headlamp in a car was measured. Since the complete model is too complex, a simplified simulation model, suitable for use in a computer simulation, is also presented. Comparison of the two results showed good agreement, and through this simulation the reliability of the presented model was confirmed.

The meshed network may become a standard for future distribution systems owing to its various benefits regarding voltage profile, reliability, losses, and the distributed generation (DG). Therefore, in Korea, there is a plan to introduce an advanced form of meshed network called a networked distribution system (NDS). This refers to a system with permanent linkages between four distribution lines (DLs) and N×N communication-based protection. To properly introduce NDS to an actual grid, this study proposes a strategy for optimal grid planning and system evaluation. Four different topologies and four practical indicators are explained. First, load imbalance is used to find the optimal grid that maximizes the load capacity. Second, line overload, fault current, and temporary overvoltage (TOV) were used to evaluate the necessity of load transfer, availability of circuit breakers, relay settings, and system stability. PSCAD/EMTDC were employed for the simulation. This study establishes the construction and evaluation guidelines of NDS for distribution system operators (DSOs).