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As a crucial component responsible for the oxygen reduction reaction (ORR), cobalt-rich perovskite-type cathode materials have been extensively investigated in protonic ceramic fuel cell (PCFC). However, their widespread application at a commercial scale is considerably hindered by the high cost and inadequate stability. In response to these weaknesses, the study presents a novel cobalt-free perovskite oxide, Ba0.95La0.05(Fe0.8Zn0.2)0.95O3-δ (BLFZ0.95), with the triple-conducting (H+|O2-|e-) property as an active and robust air electrode for PCFC. The B-site deficiency state contributes significantly to the optimization of crystal and electronic structure, as well as the increase in oxygen vacancy concentration, thus in turn favoring the catalytic capacity. As a result, the as-obtained BLFZ0.95 electrode demonstrates exceptional electrochemical performance at 700 °C, representing extremely low area-specific resistance of 0.04 Ω cm2 in humid air (3 vol.% H2O), extraordinarily high peak power density of 1114 mW cm-2, and improved resistance against CO2 poisoning. Furthermore, the outstanding long-term durability is achieved without visible deterioration in both symmetrical and single cell modes. This study presents a simple but crucial case for rational design of cobalt-free perovskite cathode materials with appreciable performance via B-site deficiency regulation.
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BACKGROUND: Hyperlipidemia is a major risk factor for vascular endothelial injury and atherosclerosis leading to cardiovascular diseases. Early diagnosis of vascular endothelial injury is important for the prevention and prognosis of cardiovascular diseases. This study aimed to investigate sensitive circulating microRNA (miRNA) as a potential diagnostic biomarker of vascular endothelial injury in a hyperlipidemic rat model. METHODS: The miRNA expression profile was detected by miRNA microarray. The hyperlipidemic rat model was established by intraperitoneal injection of vitamin D3 combined with a high-fat diet. Plasma miRNA levels were measured by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). RESULTS: No significant difference was found in the types of highly expressed miRNAs between human umbilical artery endothelial cells (HUAEC) and human umbilical vein endothelial cells (HUVEC). A total of 10 highly expressed miRNAs in endothelial cells were selected as candidate miRNAs, including miR-21, miR-126, let-7a, miR-23a, miR-221, miR-125b, miR-26a, miR-29a, miR-16, and miR-100. The plasma levels of let-7a, miR-126, miR-21, and miR-26a were significantly elevated in hyperlipidemic rats at 30 and 50 days after modeling, while the plasma level of miR-29a was significantly decreased. No significant change was found in the plasma levels of miR-125b, miR-23a, miR-221, miR-100, and miR-16. Interestingly, a significant reduction in plasma miR-29 level was detected as early as 20 days after modeling, which was earlier than for soluble intercellular adhesion molecule1 (sICAM-1). CONCLUSION: The plasma levels of endothelial cell-enriched miRNAs were correlated with vascular endothelial injury induced by hyperlipidemia. miR-29a might serve as a potential early diagnostic biomarker of endothelial injury-related diseases.
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Enfermedades Cardiovasculares , Hiperlipidemias , MicroARNs , Humanos , Animales , Ratas , Células Endoteliales , MicroARNs/genética , BiomarcadoresRESUMEN
Best management practices (BMPs) have been widely adopted to mitigate diffuse source pollutants, and the simulated processes of its pollutant reduction effectiveness suffer from manifold uncertainties, such as watershed model parameters and climate change. We presented a novel Bayesian modeling framework for BMPs planning, integrating process-based watershed modeling and Bayesian optimization algorithm to reveal the impact of multiple uncertainties. The proposed framework was applied to a BMPs planning case study in the Erhai watershed, the seventh-largest freshwater lake in China. Firstly, priority management areas (PMAs) were identified for BMPs siting using a simulation-optimization approach. Bayesian networks were subsequently embedded to reveal the multiple uncertainty sources in the optimal planning and the reliability level (RL) is introduced to represent the probability to meet the water quality target with BMPs implementation. The results suggest that ENS of discharge and nutrients concentration simulation by LSPC are both greater than 0.5, which displays satisfactory performance. The identified PMAs account for 0.8% of the total watershed areas while contribute to more than 15% of nutrient loadings reduction. The analysis of multiple uncertainty sources reveals that precipitation is the most influential source of uncertainties in BMP effectiveness. The construction of hedgerows plays an important role in the nutrient reduction. With the improvement of the reliability levels, the cost increases sharply, indicating that the implementation of BMPs has a marginal utility. The study addressed the urgent need for effective and efficient BMPs planning by identifying PMAs and addressing multi-source uncertainties.
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Contaminantes Ambientales , Contaminación del Agua , Contaminación del Agua/análisis , Incertidumbre , Teorema de Bayes , Reproducibilidad de los Resultados , Contaminantes Ambientales/análisis , LagosRESUMEN
Developing robust and highly efficient electrocatalysts for oxygen evolution reaction (OER) is critical for renewable, secure, and emission-free energy technologies. Perovskite Ba0.5 Sr0.5 Co0.8 Fe0.2 O3-δ (BSCF) has emerged as a promising OER electrocatalyst with desirable intrinsic activity. Inspired by the factor that substituting in transition-metal sublattice of the perovskite can further optimize the OER activity, herein, nickel-substituted BSCF is adopted, that is, Ba0.5 Sr0.5 Co0.8- x Fe0.2 Nix O3-δ (x = 0.05, 0.1, 0.2, denoted as BSCFNx, x = 5, 10, 20, respectively), as efficient and stable OER catalysts in alkaline solution. The phase structure, microchemistry, oxygen vacancy, and electrochemical activity of such samples are well-investigated. Endowed with an overpotential of only 278 mV at 10 mA cm-2 and a Tafel slope of merely 47.98 mV dec-1 , BSCFN20 exhibits the optimum OER activity. When constructing a two-electrode cell with BSCFN20 as anode and Pt/C as cathode (BSCFN20||Pt/C) for water splitting, it only requires a voltage of 1.63 V to achieve 50 mA cm-2 , and the BSCFN20||Pt/C remains stable within 80 h at 10 mA cm-2 , superior to the state-of-the-art RuO2 ||Pt/C counterpart. This work provides a feasible strategy for designing stable and highly active perovskite electrocatalysts for future energy storage and conversion.
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Oxygen evolution reaction (OER) is crucial in many renewable electrochemical technologies including regenerative fuel cells, rechargeable metal-air batteries, and water splitting. It is found that abundant active sites with favorable electronic structure and high electrical conductivity play a dominant role in achieving high electrocatalytic efficiency of perovskites, thus efficient strategies need to be designed to generate multiple beneficial factors for OER. Here, highlighted is an unusual super-exchange effect in ferromagnetic perovskite oxide to optimize active sites and enhance electrical conductivity. A systematic exploration about the composition-dependent OER activity in SrCo1 x Rux O3- δ (denoted as SCRx) (x = 0.0-1.0) perovskite is displayed with special attention on the role of super-exchange interaction between high spin (HS) Co3+ and Ru5+ ions. Induced by the unique Co3+ -O-Ru5+ super-exchange interactions, the SCR0.1 is endowed with abundant OER active species including Co3+ /Co4+ , Ru5+ , and O2 2- /O- , high electrical conductivity, and metal-oxygen covalency. Benefiting from these advantageous factors for OER electrocatalysis, the optimized SCR0.1 catalyst exhibits a remarkable activity with a low overpotential of 360 mV at 10 mA cm-2 , which exceeds the benchmark RuO2 and most well-known perovskite oxides reported so far, while maintaining excellent durability. This work provides a new pathway in developing perovskite catalysts for efficient catalysis.
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This paper conducts an experimental study on the axial compressive performance of FRP-steel-concrete composite columns. Nine short columns were produced and evaluated in the study, comprising of three concrete-filled steel tube reference columns and six FRP-steel-concrete composite columns, respectively denoted as "reference columns" and "composite columns". Two categories of failure modes, including shear failure and waist drum, were observed from the experiments. The failure mode may trend toward waist drum from shear failure as more FRP layers were used. The number of FRP layers had a direct effect on the level of compressive strength attained, with a greater number of layers resulting in a greater increase in compressive strength. Moreover, a greater tensile strength and higher elastic modulus of CFRP sheets are more effective at improving the compressive stiffness of the columns. Finally, a four-stage confinement mechanism for FRP-wrapped steel tube concrete composite columns is proposed and discussed, through which the damage mechanisms of the composite structures are more rationally characterized.
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Developing high-performance and cost-effective cathodes is ever-increasingly vital for the advancement of intermediate-temperature solid oxide fuel cells (IT-SOFCs). To facilitate the popularization of nonprecious metallic and cobalt-free oxygen reduction electrodes, herein, we propose a novel perovskite-based BaFeO3-δ (BF) matrix, Ba0.75Sr0.25Fe0.875Y0.125O3-δ (BSFY), as a highly active cathode for IT-SOFCs. To our satisfaction, the BSFY electrode showcases a low area-specific resistance of 0.063 Ω cm2, as well as a high peak power density of 1288 mW cm-2 at 600 °C, yielding a more than threefold improvement compared to that of its BF counterpart (371 mW cm-2). The long-term durability test highlights its practicability under the IT operating condition. When tested in 10 vol % CO2-containing air, the BSFY electrode exhibits impressive resistance against contaminants within 50 h (<0.4 Ω cm2 with a deterioration rate of â¼0.00011 Ω cm2 min-1). Coupled with its reversible response between pure air and the contaminant, the BSFY cathode is expected to be a promising cobalt-free alternative with high CO2 resistance for IT-SOFCs.
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Developing low-cost, efficient, and durable cobalt-free perovskite oxides for oxygen reduction reaction at intermediate-to-low temperatures is crucial to enhance the viability of solid oxide fuel cells (SOFCs), a promising ingredient for establishing a more sustainable future. Herein, a highly active and robust cobalt-free perovskite Ba0.75 Sr0.25 Fe0.95 P0.05 O3-δ (BSFP) oxygen electrode via a facile co-doping strategy for intermediate-to-low temperature SOFCs (ILT-SOFCs) is reported by a combined experimental and theoretical approach. Attributed to stable and oxygen defect-rich structure, and remarkable intrinsic oxygen transport kinetics, the BSFP cathode shows exceptional catalytic performance, including record-level power output among iron-based perovskite cathodes (1464 mW cm-2 at 600 °C), low area-specific resistance (≈0.1 Ω cm2 at 600 °C), robust stability both in symmetrical and single cell configurations, and outstanding CO2 tolerance/reversibility. The first-principle calculations validate the role of co-doping of strontium and phosphorus for the high activity and durability. Central to this work is the combined experiment-calculation approach to point to an effective strategy in the development of highly active and stable perovskite-type cathodes for ILT-SOFCs and related applications.
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An accurate estimation of thaw depth is critical to understanding permafrost changes due to climate warming on the Qinghai-Tibetan Plateau (QTP). However, previous studies mainly focused on the interannual changes of active layer thickness (ALT) across the QTP, and little is known about the changes in the seasonal thaw depth. Machine learning (ML) is a critical tool to accurately estimate the ALT of permafrost, but a direct comparison of ML with deep learning (DL) in ALT projection regarding the model performance is still lacking. Here, ML, namely random forest (RF), and DL algorithms like convolutional neural networks (CNN) and long short-term memory (LSTM) neural networks were compared to estimate the interannual changes of ALT and seasonal thaw depth on the QTP. Meteorological series, in-situ collected ALT observations, and geospatial information were used as predictors. The results show that both ML and DL methods are capable of estimating ALT and seasonal thaw depth in permafrost areas. The CNN and LSTM models developed using longer lagging times exhibit better performance in thaw depth prediction while the RF models are either mediocre or sometimes even worse as the lagging time increases. The results show that the ALT from 2003 to 2011 on the QTP exhibits an increasing trend, especially in the northern region. In addition, 68.8%, 88.7%, 52.5%, and 47.5% of the permafrost regions on the QTP have deepened seasonal thaw depth in spring, summer, autumn, and winter, respectively. The correlation between air temperature and permafrost thaw depth ranges from 0.65 to 1 with the time lag ranging from 1 to 32 days. This study shows that ML and DL can be effectively used in retrieving ALT and seasonal thaw depth of permafrost, and could present an efficient way to figure out the interannual and seasonal variations of permafrost conditions under climate warming.
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Hielos Perennes , Memoria a Corto Plazo , Redes Neurales de la Computación , Estaciones del Año , TibetRESUMEN
Objective:To review the key points of the perioperative period management of laryngotracheoplasty using free hyoid grafting in children with acquired subglottic stenosis, in order to reduce postoperative complications, to improve extubation rate, and to promote the rehabilitation of the patients. Methods:Twenty-five cases with subglottic stenosis were treated by laryngotracheoplasty using free hyoid grafting in department of Otolaryngology, Head and Neck Surgery, Shanghai Children's Hospital from September 2017 to June 2021. Standardized perioperative period management protocols were carried out in all 25 cases. Results:21 cases were successfully extubated, T tubes of 2 cases were replaced by tracheal tubes which have been sealed, but tracheal tubes sealing was failed in 2 cases after tube replacement. Conclusion:High quality perioperative period management of laryngotracheoplasty using free hyoid grafting can effectively reduce related complication rate, maintain airway patency, promote laryngeal function recovery, shorten the period of tracheotomy and improve the quality of life.
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Laringoestenosis , Laringe , Niño , China , Cartílago Cricoides/cirugía , Humanos , Lactante , Laringoestenosis/cirugía , Laringe/cirugía , Periodo Perioperatorio , Calidad de VidaRESUMEN
Food production systems, urbanization, and other anthropogenic activities dramatically alter natural hydrological and nutrient cycles, and are primarily responsible for water quality impairments in China's rivers. This study compiled a 16-year (2003-2018) dataset of river water quality (161,337 records from 2424 sites), watershed/landscape features, and meteorological conditions to investigate the spatial water quality patterns and underlying drivers of river impairment (defined as water quality worse than Class V according to China's Environmental Quality Standards for Surface Waters, GB3838-2002) at a national scale. Our analysis provided evidence of a distinct water quality improvement with a gradual decrease in the frequency of prevalence of anoxic conditions, an alleviation of the severity of heavy metal pollution, whereas the cultural eutrophication has only been moderately mitigated between 2003 and 2018. We also identified significant spatial variation with relatively poorer water quality in eastern China, where 17.2% of the sampling sites registered poor water quality conditions, compared with only 4.6% in western China. Total phosphorus (TP) and ammonia-nitrogen (NH3-N) are collectively responsible for >85% of the identified incidences of impaired conditions. Bayesian modelling was used to delineate the most significant covariates of TP/NH3-N riverine levels in six large river basins (Liao, Hai, Yellow, Yangtze, Huai, and Pearl). Water quality impairments are predominantly shaped by anthropogenic drivers (82.5% for TP, 79.5% for NH3-N), whereas natural factors appear to play a secondary role (20.5% for TP, 17.5% for NH3-N). Two indicator variables of urbanization (urban areal extent and nighttime light intensity) and farmland areal extent were the strongest predictors of riverine TP/NH3-N levels and collectively accounted for most of the ambient nutrient variability. We concluded that there is still a long way to go in order to eradicate eutrophication and realize acceptable ecological conditions. The design of the remedial measures must be tailored to the site-specific landscape characteristics, meteorological conditions, and should also consider the increasing importance of non-point source pollution and internal nutrient loading.
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Ríos , Contaminantes Químicos del Agua , Teorema de Bayes , China , Monitoreo del Ambiente , Eutrofización , Nitrógeno/análisis , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , Calidad del AguaRESUMEN
Endothelial cell senescence is closely related to the occurrence of cardiovascular diseases and microRNAs (miRNAs/miRs) are considered as therapeutic targets for cardiovascular disease. The current study aimed to investigate the role of miR20b in the senescence process of endothelial cells and its underlying mechanism. Cell viability, proportion of senescent cells and the cell cycle were respectively determined by Cell Counting Kit8, SAßgalactosidase and flow cytometry. The relative expressions of mRNA and protein were detected by reverse transcriptionquantitative polymerase chain reaction and western blotting, respectively. The possible target genes and binding sites of miR20b were predicted using Targetscan and further verified by dual luciferase reporter assay. The present study found that H2O2 inhibited cell viability, caused cell cycle arrest in G1 phase, decreased miR20b level and induced cell senescence. Moreover, high expression of miR20b promoted cell viability and reduced H2O2induced cell senescence, whereas low expression of miR20b produced the opposite effects. Thioredoxin interacting protein (TXNIP) was predicted as a target gene for miR20b and knockdown of TXNIP increased cell viability, inhibited cell senescence, reduced the expression of p16, p21, TXNIP, NLR family pyrin domain containing 3 (NLRP3) and cleaved Caspase1 and reversed the promoting effects of the miR20b inhibitor and H2O2 on cell senescence. Furthermore, the knockdown of TXNIP inhibited the Wnt/ßcatenin pathway. The finding reveals that high expression of miR20b inhibits the senescence of human umbilical vein endothelial cells through regulating the Wnt/ßcatenin pathway via the TXNIP/NLRP3 axis.
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Senescencia Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , MicroARNs/farmacología , Vía de Señalización Wnt/efectos de los fármacos , Proteínas Portadoras/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Humanos , Peróxido de Hidrógeno , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , beta Catenina/metabolismoRESUMEN
China has made considerable efforts to mitigate the pollution of lakes over the past decade, but the success rate of these restoration actions at a national scale remains unclear. The present study compiled a 13-year (2005-2017) comprehensive dataset consisting of 24,319 records from China's 142 lakes and reservoirs. We developed a novel Water Quality Index (WQI-DET), customized to China's water quality classification scheme, to investigate the spatio-temporal pollution patterns. The likelihood of regime shifts during our study period is examined with a sequential algorithm. Our analysis suggests that China's lake water quality has improved and is also characterized by two WQI-DET abrupt shifts in 2007 and 2010. However, we also found that the eutrophication problems have not been eradicated and heavy metal (HM) pollution displayed an increasing trend. Our study suggests that the control of Cr, Cd and As should receive particular attention in an effort to alleviate the severity of HM pollution. Priority strategies to control HM pollution include the reduction of the contribution from mining activities and implementation of soil remediation in highly polluted areas. The mitigation efforts of lake eutrophication are more complicated due to the increasing importance of internal nutrient loading that can profoundly modulate the magnitude and timing of system response to external nutrient loading reduction strategies. We also contend that the development of a rigorous framework to quantify the socioeconomic benefits from well-functioning lake and reservoir ecosystems is critically important to gain leeway and keep the investments to the environment going, especially if the water quality improvements in many Chinese lakes and reservoirs are not realized in a timely manner.
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Restauración y Remediación Ambiental , Lagos , China , Ecosistema , Eutrofización , Lagos/química , Metales Pesados/análisis , Minería , Calidad del AguaRESUMEN
Excess nitrogen (N) export from lowland artificial watersheds (polders) is often assumed to be a major contributor to the cultural eutrophication of downstream aquatic ecosystems. However, the complex transport processes characterizing lowland areas pose significant challenges in accurately quantifying their actual role. In this study, we developed a dynamic model to track N sources and transport pathways in lowland polders. The model is able to accommodate all the unique characteristics of polder dynamics, including artificial drainage, and interactions among surface water, groundwater and soil water. Our model was calibrated and validated against water level data and nitrogen concentrations measured in a lowland polder (Polder Jian) in China during the 2014-2016 period. Model performance was satisfactory with an R2 value of 0.55 and an NS value of 0.53 for total N concentrations. The characterization of the various components of water budget and N cycle derived by the model was on par with local empirical estimates. N export from Polder Jian was approximately 57â¯kgâ¯ha-1 yr-1 and was distinctly higher than values reported from nearby non-polder areas. The largest fraction of N export stemmed from seepage. To our knowledge, this is the first dynamic model to quantify N export from a watershed with artificial drainage network and can be used to design remedial measures of ecosystem degradation.
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Modelos Teóricos , Nitrógeno/análisis , Contaminantes del Suelo/análisis , Movimientos del Agua , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua , China , Monitoreo del Ambiente , Eutrofización , Agua Dulce , Agua Subterránea , SueloRESUMEN
Water quality management and load reduction are subject to inherent uncertainties in watershed systems and competing decision objectives. Therefore, optimal decision-making modeling in watershed load reduction is suffering due to the following challenges: (a) it is difficult to obtain absolutely "optimal" solutions, and (b) decision schemes may be vulnerable to failure. The probability that solutions are feasible under uncertainties is defined as reliability. A reliability-oriented multi-objective (ROMO) decision-making approach was proposed in this study for optimal decision making with stochastic parameters and multiple decision reliability objectives. Lake Dianchi, one of the three most eutrophic lakes in China, was examined as a case study for optimal watershed nutrient load reduction to restore lake water quality. This study aimed to maximize reliability levels from considerations of cost and load reductions. The Pareto solutions of the ROMO optimization model were generated with the multi-objective evolutionary algorithm, demonstrating schemes representing different biases towards reliability. The Pareto fronts of six maximum allowable emission (MAE) scenarios were obtained, which indicated that decisions may be unreliable under unpractical load reduction requirements. A decision scheme identification process was conducted using the back propagation neural network (BPNN) method to provide a shortcut for identifying schemes at specific reliability levels for decision makers. The model results indicated that the ROMO approach can offer decision makers great insights into reliability tradeoffs and can thus help them to avoid ineffective decisions.
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The widespread application of solid oxide fuel cell technology requires the development of innovative electrodes with high activity for oxygen reduction reaction (ORR) at intermediate temperatures. Here, we demonstrate that a cobalt-free parent oxide BaFeO(3-δ) (BF), which lacks long-range oxygen-ion diffusion paths, has surprisingly high electrocatalytic activity for ORR. Both in situ high-temperature X-ray diffraction analysis on room-temperature powder and transmission electron microscopy on quenched powder are applied to investigate the crystal structure of BF. Despite the lack of long oxygen-ion diffusion paths, the easy redox of iron cations as demonstrated by thermal gravimetric analysis (TGA) and oxygen temperature-programmed desorption and the high oxygen vacancy concentration as supported by iodometric titration and TGA benefit the reduction of oxygen to oxygen ions. Moreover, the electrical conductivity relaxation technique in conjunction with a transient thermogravimetric study reveals very high surface exchange kinetics of BF oxide. At 700 °C, the area specific resistance of BF cathode, as expressed by a symmetrical cell configuration, is only â¼0.021 Ω cm(2), and the derived single fuel cell achieves high power output with a peak power density of 870 mW cm(-2). It suggests that an undoped BF parent oxide can be used as a high-efficiency catalyst for ORR.
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China is confronting the challenge of accelerated lake eutrophication, where Lake Dianchi is considered as the most serious one. Eutrophication control for Lake Dianchi began in the mid-1980s. However, decision makers have been puzzled by the lack of visible water quality response to past efforts given the tremendous investment. Therefore, decision makers desperately need a scientifically sound way to quantitatively evaluate the response of lake water quality to proposed management measures and engineering works. We used a water quality modeling based scenario analysis approach to quantitatively evaluate the eutrophication responses of Lake Dianchi to an under-construction water diversion project. The primary analytic framework was built on a three-dimensional hydrodynamic, nutrient fate and transport, as well as algae dynamics model, which has previously been calibrated and validated using historical data. We designed 16 scenarios to analyze the water quality effects of three driving forces, including watershed nutrient loading, variations in diverted inflow water, and lake water level. A two-step statistical analysis consisting of an orthogonal test analysis and linear regression was then conducted to distinguish the contributions of various driving forces to lake water quality. The analysis results show that (a) the different ways of managing the diversion projects would result in different water quality response in Lake Dianchi, though the differences do not appear to be significant; (b) the maximum reduction in annual average and peak Chl-a concentration from the various ways of diversion project operation are respectively 11% and 5%; (c) a combined 66% watershed load reduction and water diversion can eliminate the lake hypoxia volume percentage from the existing 6.82% to 3.00%; and (d) the water diversion will decrease the occurrence of algal blooms, and the effect of algae reduction can be enhanced if diverted water are seasonally allocated such that wet season has more flows.
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Eutrofización/fisiología , Lagos/microbiología , Modelos Biológicos , Movimientos del Agua , Contaminación del Agua/prevención & control , Calidad del Agua/normas , China , Lagos/química , Modelos LinealesRESUMEN
OBJECTIVE: To analyze the effects of hyaluronidase and hirudoid treatment on drug extravasation in neonates. METHODS: The medical records of 13 neonates with drug extravasation treated with hyaluronidase and hirudoid between August 1(st), 2010 and May 1(st), 2012 were analyzed retrospectively. The treatment procedure for drug extravasation adhered to the protocol in neonatal department. The information including age, sex, weight, diagnosis, size of affected area, site of extravasation and treatment was collected. Findings : The extravasation injuries alleviated and the symptoms improved after treatment, no adverse drug effects were reported with use of hyaluronidase and hirudoid. CONCLUSION: The treatment appeared to be beneficial in the management of extravasations of various medications in neonates and may be useful in reducing the severity of cutaneous toxicosis. However, further studies with large samples are still needed to assess the effectiveness and safety of hyaluronidase and hirudoid.
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Higher order cumulants (HOC) is a new kind of modern signal analysis of theory and technology. Spectrum entropy clustering (SEC) is a data mining method of statistics, extracting useful characteristics from a mass of nonlinear and non-stationary data. Following a discussion on the characteristics of HOC theory and SEC method in this paper, the study of signal processing techniques and the unique merits of nonlinear coupling characteristic analysis in processing random and non-stationary signals are introduced. Also, a new clustering analysis and diagnosis method is proposed for detecting multi-damage on gear by introducing the combination of HOC and SEC into the damage-detection and diagnosis of the gear system. The noise is restrained by HOC and by extracting coupling features and separating the characteristic signal at different speeds and frequency bands. Under such circumstances, the weak signal characteristics in the system are emphasized and the characteristic of multi-fault is extracted. Adopting a data-mining method of SEC conducts an analysis and diagnosis at various running states, such as the speed of 300 r/min, 900 r/min, 1200 r/min, and 1500 r/min of the following six signals: no-fault, short crack-fault in tooth root, long crack-fault in tooth root, short crack-fault in pitch circle, long crack-fault in pitch circle, and wear-fault on tooth. Research shows that this combined method of detection and diagnosis can also identify the degree of damage of some faults. On this basis, the virtual instrument of the gear system which detects damage and diagnoses faults is developed by combining with advantages of MATLAB and VC++, employing component object module technology, adopting mixed programming methods, and calling the program transformed from an *.m file under VC++. This software system possesses functions of collecting and introducing vibration signals of gear, analyzing and processing signals, extracting features, visualizing graphics, detecting and diagnosing faults, detecting and monitoring, etc. Finally, the results of testing and verifying show that the developed system can effectively be used to detect and diagnose faults in an actual operating gear transmission system.