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Nitric oxide (NO) mediated transmission in the dorsal raphe nucleus (DRN) has been shown to be involved in the modulation of anxiety-like behaviors. We investigated whether inhibition of nitric oxide synthase (NOS) in the DRN would prevent anxiety-like behavior induced by ethanol withdrawal. Male Wistar rats were treated with ethanol 2-6% (v/v) for a period of 21 days. Ethanol withdrawal was induced by abrupt discontinuation of the treatment. Experiments were performed 48 h after ethanol discontinuation. Rats with a guide cannula aimed at the DRN received intra-DRN injections of the non-selective NOS inhibitor NG-nitro-l-arginine methyl ester (l-NAME), selective neuronal NOS (nNOS) inhibitor N(ω)-propyl-l-arginine (NPLA), or selective inhibitor of inducible NOS (iNOS) N-([3-(aminomethyl)phenyl] methyl) ethanimidamidedihydrochloride (1400W). Five minutes later, the animals were tested in the elevated plus maze (EPM). Plasma ethanol levels were determined by gas chromatography. There was a reduction in plasma ethanol levels 48 h after ethanol withdrawal. Rats from the ethanol withdrawal group showed decreased exploration of the open arms of the EPM with no change in the exploration of enclosed arms. Intra-DRN treatment with l-NAME (100 nmoles/0.2 μL) and 1400W (1 nmol/0.2 μL), but not NPLA (10 nmoles/0.2 μL) in the DRN attenuated the decrease in the exploration of the open arms of the EPM induced by ethanol withdrawal. The major new finding of the present study is that iNOS in the DRN plays a role in the anxiety-like behavior induced by ethanol withdrawal.

The study focuses on the simultaneous improvement of biomass, lipid, and docosahexaenoic acid (DHA) productivities in a single reactor using modulator control strategies. The efficacy of three different biochemical modulators, sesamol (Ses), 6-benzylaminopurine (6-BAP), and ethylenediaminetetraacetic acid (EDTA), as potential stimulants in augmenting the biomass, lipid, and DHA production of Schizochytrium sp. MTCC 5890 was elucidated. After 48 h of cultivation, among tested modulators, the individual supplementation of 6-BAP and Ses showed improvement in biomass, lipid, and DHA accumulation by 28.2%, 56.1%, and 87.2% and 21.7%, 47.9%, and 91%, respectively, over the non-supplemented group. In addition, the cooperative effect of selected concentrations, i.e., 10 mgL-1 6-BAP and 200 mgL-1 Ses, further increased the productivities of biomass of 13.5 gL-1d-1 ± 0.66, lipid of 7.4 gL-1d-1 ± 0.69, and DHA of 3.2 gL-1d-1 ± 1.09 representing 8%, 39%, and 69% increase over the individual addition of 6-BAP or Ses, respectively, in batch culture. Supplementation with 6-BAP + Ses at 12 h of time point eventually increased the lipid yield to 15.6 ± 0.42 gL-1 from 7.88 ± 0.31 gL-1 (control) and DHA yield to 6.4 ± 0.11 gL-1 from 2.23 ± 0.09 gL-1 (control), respectively. Furthermore, the process was optimized in continuous culture supplemented with 6-BAP + Ses for enhanced productivities. Continuous culture resulted in maximum biomass (2.04 ± 1.12 gL-1 day-1), lipid (1.0 ± 0.73 gL-1 day-1), and DHA (0.386 ± 0.22 gL-1 day-1) productivities, which were higher as compared with the batch and fed-batch processes by 26 ± 1.21%, 22 ± 1.01%, and 21 ± 0.98% and 24 ± 0.45%, 16 ± 0.38%, and 14 ± 0.12%, respectively. This work represents the potential application of the combined effect of modulators for the simultaneous enhancement of biomass production and lipid and DHA productivities. KEY POINTS: • The cumulative study of 6-BAP and sesamol proved to be more efficient in the simultaneous production of biomass, lipid, and DHA in a single reactor. • Addition of a combination of 6-BAP + Ses remarkably increased the biomass, lipid, and DHA productivities in tandem in continuous culture.

Guaranteeing a robust and reliable wind turbine design under increasingly demanding conditions requires an expert insight into dynamic loading effects of the complete turbine and its subsystems. Traditionally, aeroelastic codes are used to model the wind turbine, where the gearbox is reduced to a few or only one degree of freedom, as bring limitations to describe the dynamic behavior in detail. In this paper, the gearbox dynamic behavior is assessed by means of three multibody models of varying complexity, which are assessed based on modal and dynamic behaviors. This work shows that the fully flexible multibody dynamic model can better reflect the operating condition of the wind turbine. However, due to high calculation precision, the fully flexible multibody dynamic model consumes much times. Therefore, an artificial neural network method is proposed for the prediction of wind turbine dynamic behaviors. The results show that combination of the multibody method and the artificial neural network can reduce the simulation runtime, guaranteeing the accuracy meantime. Therefore, it is of great significance in engineering practice.

Abstract To improve the performance of organic Rankine cycle (ORC) system, this paper proposes to replace the electric working fluid pump with multi-stage gas-liquid booster pump which is driven by high pressure gas generated in evaporator of ORC system. This pump consists of four gas-liquid booster pumps. The working principle of gas-liquid booster pump and multi-stage gas-liquid booster pump are introduced respectively. By using high pressure air as driving force and water as pressurized working fluid, the performance of multi-stage gas-liquid booster pump is tested experimentally. The experimental results of this study mainly consist of two parts: the first part focuses on the pump performance with various pressure at pump inlet and outlet while valve at pump inlet is completely open; the second part focuses on various valve open ratio at pump inlet which is operated at fixed inlet and outlet pressure of 1.8 MPa and 0.15 MPa. The results show that the pump conversion efficiency decreases with the increase of inlet pressure and the decrease of outlet pressure. The maximum conversion efficiency, volume flow rate of water and volume flow rate of high pressure air are 0.72, 0.55 L/s and 0.42 L/s respectively. When the pump is operated at different valve open ratio, the volume flow rate of water and high pressure air decreases with the decrement of valve open ratio. In addition, the conversion efficiency almost maintains identical under different valve open ratio.

Abstract The process of spontaneous combustion of coal and coal waste gobs including emitted gases, condensation of inorganic and organic species in vents, and leachable potential are examined in this study which encompasses a literature review and new experimental data. Furthermore, the potential environmental benefits of cover soil reclamation for reduction of atmospheric and water leachable pollutant emissions are also considered. The Datong district (Shanxi province) is one of the most important coal production areas in China. The resulting large accumulations of mining waste are susceptible to spontaneous combustion. Three coal gangue dumps in the Datong region subjected to a range of reclamation conditions were investigated to assess the influence on coal fires. Coal, coal gangue, and condensates from gaseous emissions were characterized in terms of chemical composition, particle morphology, mineralogy, and leaching potential. The condensates include tar-like deposits, elemental sulfur, gypsum/anhydrite, ammonium and Hg salts, and a broad array of Al–K–Fe sulfates. The latter may give rise to strongly acidic leachates with high metal loads, which may pose a serious threat to the environment. These findings led to the development of a proposed condensation sequence model for coal gangue fires. The presence and distribution of organic compounds in the condensates deposited at vents were used as geothermometers in support of the proposed condensation model. Additionally, the present study has also explored some feasible remediation measures. It was found that covering these coal waste dumps with a layer of compacted soils appears to be an excellent cost-effective method to reduce spontaneous combustion, scavenge pollutants from gaseous emissions, and minimize risks associated with the leaching of readily soluble salts condensed on the surface.

The Tibetan Plateau holds some of the world's highest undisturbed natural treelines and timberlines. Such extreme environments constitute potentially valuable monitoring sites of the effects of climate warming on high-elevation forests. Here, we analyze a network of 21 Smith fir forests situated in the Sygera Mountains, southeastern Tibetan Plateau, using tree-ring width (TRW) and basal area increment (BAI) chronologies. Sampled sites encompassed a wide elevation gradient, from 3600 to 4400 m, including some treeline sites and diverse aspects and tree ages. In comparison with TRW series, BAI series better capture the long-term warming signal. Previous November and current April and summer temperatures are the dominant climatic factors controlling Smith fir radial growth. The mean inter-series correlations of TRW increased upwards, but the forest limit presented the highest potential to reconstruct past temperature variability. Moreover, the growth responses of young trees were less stable than those of trees older than 100 years. Climate warming is accelerating radial growth of Smith fir forest subjected to mesic conditions. Collectively, these findings confirm that the effects of site elevation and tree age should be considered when quantifying climate-growth relationships. The type of tree-ring data (BAI vs. TRW) is also relevant since BAI indices seem to be a better climatic proxy of low-frequency temperature signals than TRW indices. Therefore, site (e.g., elevation) and tree (e.g., age) features should be considered to properly evaluate the effects of climate warming on growth of high-elevation forests.

AbstractA new polymer acceptor poly{(N,N′‐bis(2‐ethylhexyl)‐1,4,5,8‐naphthalenedicarboximide‐2,6‐diyl)‐alt‐5,5‐(3,3′‐didodecyl‐2,2′‐bifuran)} (NDI‐BFR) made from naphthalenediimide (NDI) and furan‐derived head‐to‐head‐linked 3,3′‐dialkyl‐2,2′‐bifuran (BFR) units is reported in this study. Compared to the benchmark polymer poly(naphthalenediimide‐alt‐bithiophene) (N2200), NDI‐BFR exhibits a larger bathochromic shift of absorption maxima (842 nm) with a much higher absorption coefficient (7.2 × 104 m−1 cm−1), leading to an ultranarrow optical bandgap of 1.26 eV. Such properties ensure good harvesting of solar light from visible to the near‐infrared region in solar cells. Density functional theory calculation reveals that the polymer acceptor NDI‐BFR possesses a higher degree of backbone planarity versus the polymer N2200. The polymer NDI‐BFR exhibits a decent electron mobility of 0.45 cm2 V−1 s−1 in organic thin‐film transistors (OTFTs), and NDI‐BFR‐based all‐polymer solar cells (all‐PSCs) achieve a power conversion efficiency (PCE) of 4.39% with a very small energy loss of 0.45 eV by using the environmentally friendly solvent 1,2,4‐trimethylbenzene. These results demonstrate that incorporating head‐to‐head‐linked BFR units in the polymer backbone can lead to increased planarity of the polymer backbone, reduced optical bandgap, and improved light absorbing. The study offers useful guidelines for constructing n‐type polymers with narrow optical bandgaps.

In order to fully tap the absorption potential of power grid regulation resources, including power sources, controllable load and energy storage, an optimal dispatch method based on source-network-load-storage interaction was proposed to realize the effective connection between power grid operation economy and new energy absorption. The operation characteristics of conventional power source, controllable load and energy storage is firstly studied including their operation cost and generation output regulation characteristics. Thus, the operation characteristic functions of the above regulating resources are constructed. Then, an optimal dispatch model considering source-network-load-storage interaction is proposed. The model aims to minimize the comprehensive power grid operation cost and the new energy power loss cost. And the power grid stable operation constraints and regulation resources operation constraints are also taken into consideration. Finally, a case study based on IEEE-30 buses system is constructed to verify the effectiveness of the proposed method.

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