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In order to reveal the electrostatic enhancement filtration effect of a dual-layer granular bed filter with an external electric field, a coupled numerical model was established, including the flow field, discrete particle field, electric field and particle collision rebound effect, then the electrostatic enhancement filtration effect of each filter layer was calculated and investigated under different filtration velocities, different temperatures and different electric field intensities, respectively. The results show that the grade filtration efficiencies of the upper and lower filter layers decrease with the increase of filtration velocity, the electrostatic enhancement filtration effect of the external electric field on the fine particles is more obvious, the electrostatic enhancement filtration effect of the upper filter layer is greater at low velocity, and the electrostatic enhancement filtration effect of the lower filter layer is greater at high velocity. The grade filtration efficiencies of the upper and lower filter layers decrease with the increase in temperature, and the electrostatic enhancement filtration effect is more obvious at low temperatures. The grade filtration efficiencies of the upper and lower filter layers increase with the increase of electric field intensity. [Display omitted] • Simulation of electrostatically enhanced granular bed filter. • Local electric fields enhance at the gap and contact of the granules. • Filtration efficiency decreases with velocity increase due to particle rebound. • The electrostatic enhancement filtration effect is larger for fine particles. [ABSTRACT FROM AUTHOR]

To evaluate the burner location's role on the flow-field deflection and asymmetric combustion that occurring in a 600 MW e supercritical down-fired boiler, cold-modeling gas/particle flow experiments and numerical simulations on coal combustion were performed with varying the furnace arch's burner location. Meanwhile, full-load industrial-size measurements at the boiler's design setup were performed to uncover the asymmetric combustion characteristics and verify the simulation validity. The boiler's design setup displayed a severely deflected gas/particle flow field with (i) a large downward gas/particle flow penetration difference appearing in the front- and rear-half sides and (ii) the upward flow fully deflecting towards the front-half side. Accordingly, a badly asymmetric combustion performance (much lower gas temperature levels appearing in the front-half side than in the rear-half side) occurred with poor burnout and high NO x emissions. The calculated coal/air penetration and flow-field deflection extent were found to be shallower than the cold-modeling experimental versions, despite the consistent flow-field deflection pattern respectively gained by the two methods. Positioning burners towards the front/rear wall greatly improved the flow-field deflection in the form of apparently decreasing the aforementioned penetration difference and redirecting the upward gas/particle flow in the furnace’s central part. Consequently, asymmetric combustion sharply weakened to increase burnout and reduce NO x emissions. In contrast, moving burners towards the furnace centerline aggravated the flow-field deflection and asymmetric combustion to worsen the furnace performance in burnout and NO x production. These results suggest that in the absence of coal/air distribution with varying burner location, the local high gas temperatures incurred by asymmetric combustion facilitate the NO x production. Finally, burners are recommended to position towards the front/rear wall as much as possible for weakening the flow-field deflection and asymmetric combustion if a lowered manufacturing cost requires a short upper furnace where the asymmetric upper furnace configuration effect is aggravated. [ABSTRACT FROM AUTHOR]

Objective: The choice of surgical strategy for patients with proximal gastric cancer remains controversial. In this study, we recommend that a new reconstruction procedure be performed following proximal gastrectomy. Methods: We conducted a retrospective study involving 71 patients who underwent gastrectomy for proximal gastric cancer. Clinicopathological features, postoperative complications, nutritional status, and overall survival (OS) rate were compared among three different reconstruction approaches. Results: There were 34 cases of proximal gastrectomy followed by esophagogastrostomy reconstruction (EG), 16 cases of total gastrectomy and Roux-en Y reconstruction (RY) and 21 cases of proximal gastrectomy followed by esophagogastrostomy plus gastrojejunostomy reconstruction (EGJ). Though the clinicopathological features, the nutritional status and OS rate were similar among the three groups of patients, the incidence of reflux esophagitis was significantly higher in the EG group (35.3 %) than the RY (6.2 %) and EGJ (9.6 %) groups( P < 0.05). Few EGJ patients suffered from either reflux esophagitis or anastomotic stenosis. Conclusions: The EGJ reconstruction method helps to resolve the syndrome of reflux esophagitis. Our data indicates that it is a simple, safe, and effective reconstruction procedure for PGC. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the genetic defects in two families with classic congenital adrenal hyperplasia (CAH). Clinical data and vein blood of the family members were collected, hormonal evaluation, karyotype analysis, ultrasound and CT scans were performed, and a direct-sequencing of PCR products of the candidate genes was used to identify the mutations. In family A, Patients A-II:1 and A-II:2 were found to be in a compound heterozygous state for mutations of p.I172N (g.1004T>A) in exon 4 and IVS2-13A/C>G (g.659A/C>G) in intron 2 in CYP21A2 gene, their father A-I:1 and mother A-I:2 were found to carry a heterozygous mutation of IVS2-13A/C>G (g.659A/C>G) and p.I172N (g.1004T>A) respectively. In family B, Patient B-II:1 was detected to carry only one heterozygous mutation of p.I172N; no other mutations in CYP11B1, CYP17A1 or HSD3B2 genes were detected. Her father B-I:1 carried a heterozygous mutation of p.I172N (g.1004T>A) and her mother B-I:2 was found to be a wild type in all the candidate genes. Obviously, patients A-II:1 and A-II:2 inherited the p.I172N (g.1004T>A)-bearing maternal allele and the IVS2-13A/C>G (g.659A/C>G)-bearing paternal allele. And this kind of compound heterozygous mutations caused simple virilising (SV) CAH. While patient B-II:1, whose phenotype was SV CAH too, was found to carry only one heterozygous mutation of the p.I172N (g.1004T>A)-bearing paternal allele, and needed further studies. [Copyright &y& Elsevier]

The wind turbine has rapidly developed worldwide with increasing height and scale, resulting in the increased risk of lightning strikes. When wind turbines were stroke by the lightning, they will be damaged, causing economic loss and outage. Lightning risk assessment can guide the improvement of lightning protection and the design of the wind farms to efficiently prevent lightning damages. The traditional lightning risk assessment methods rely on subjective features to some extent. The existing lightning risk assessment methods based on machine learning demand abundant labeled data. It is extremely difficult to label and acquire the data. This paper proposed a lightning risk assessment method based on semi-supervised learning to address the challenges of labeling negative samples and limited labeled data. The semi-supervised K-means algorithm is proposed to divide all data into three parts. The Laplacian support vector machine (LapSVM) with hyperparameters optimized by the particle swarm optimization (PSO) is used to assess the lightning risk. The proposed method has better performance than the standard SVM and neural network (NN). Moreover, previous researches did not consider lightning protection ability. This paper introduces the receptor number into lightning risk assessment. The assessment results suggest that there is higher lightning risk in areas with a great number of wind turbines, high lightning density, and strong lightning strength. The ocean area is more likely to have low lightning risk. The results are valuable for lightning protection optimization of existing wind farms and can give guidance for the plan of new wind farms. [ABSTRACT FROM AUTHOR]

To improve the filtration efficiency of the dual-layer granular bed filter, a new method to enhance filtration with dust bipolar-charging was proposed. The characteristics of positive and negative corona discharge and dust charging at different temperatures were measured and analyzed. The filtration experiments of non-charged dust, positive charged dust, negative charged dust, and bipolar charged dust in a dual-layer granular bed filter were carried out. The results confirmed that the best filtration effect was achieved when the dust was bipolar-charged. Furthermore, because of the loose structure of dust cake formed by the charged dust, the filter regeneration cycles were prolonged. At 450 ℃, when the inlet dust concentration was 10 g/m3, and the bi-charging voltages were + 20 kV and - 14 kV, the mean outlet dust concentration in a filtering cycle was 38.1%, 46.6% and 68.2% lower than that of negative-charged, positive charged, and non-charged dust, respectively. [ABSTRACT FROM AUTHOR]

Abstract Background Hepatocellular carcinoma (HCC) is the most common malignant tumor worldwide. Circular RNAs (circRNAs), a new class of endogenous non-coding RNAs, are widespread and abundant in mammalian cells. Cumulative evidence showed that circRNAs play significant roles in the process of cancer. However, the expression and function of circRNAs in HCC remain to be investigated. Methods The expression of circular RNA SMARCA5 (circSMARCA5) in tissues and plasma samples was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The role of circSMARCA5 in HCC progression was assessed by in vitro experiments. A receiver operating characteristic (ROC) curve was established to evaluate the value of circSMARCA5 as a biomarker in HCC. Results The expression of circSMARCA5 was significantly downregulated in HCC tissues compared with para-carcinoma tissues. CircSMARCA5 levels were correlated with tumor differentiation (p = 0.023), Tumor-node-metastasis (TNM) stage (p = 0.001), cancer invasion (p = 0.004), as well as cancer diameter (p = 0.018). In vitro cell experiments revealed that overexpression of circSMARCA5 resulted in inhibited proliferation, increased apoptosis and suppressed invasion. Moreover, we found that circSMARCA5 expression was down-regulated in plasma samples of patients with HCC. The ROC curve analyses revealed that plasma circSMARCA5 showed a high accuracy (AUC = 0.938, 0.853, 0.711) for diagnosing HCC from healthy controls, hepatitis and cirrhosis. The area under the ROC curve of plasma circSMARCA5 in combination with AFP in diagnosing HCC from hepatitis and cirrhosis was 0.903 and 0.858. Especially, plasma circSMARCA5 presented a high accuracy (AUC = 0.847, 0.706) for detecting HCC with serum AFP below 200 ng/ml from those hepatitis and cirrhosis with AFP below 200 ng/ml. Conclusion Our study revealed that circSMARCA5 may promote apoptosis, inhibit proliferation, invasion and metastasis of HCC cells. CircSMARCA5 may serve as a potential prediction and monitor biomarker for HCC, especially in HCC patients with AFP blow the cutoff value. Highlights • CircSMARCA5 is down-regulated in plasma and tumor tissue of HCC patients. • CircSMARCA5 expression is HCC-stage-specific. • CircSMARCA5 plays a role in apoptosis, proliferation, invasion and metastasis. • CircSMARCA5 may serve as a potential prediction biomarker for HCC. [ABSTRACT FROM AUTHOR]

To expand the application of acylated blueberry pomace anthocyanins in food and nutraceuticals, their enzymatic acylation reaction and the cytotoxic response were explored. In this study, enzymatic acylation was carried out with cyanidin-3- O -glucoside (C3G) as the main body and Novozyme 435 as the biocatalyst. With a series of improvements, the reaction was carried out under the conditions of lauric acid as the acyl donor, tert-amyl alcohol as the reaction medium, the molar ratio of C3G to lauric acid of 1:10, the reaction time of 24 h and the reaction temperature of 60 °C, and 35.29 % acylation rate was obtained. Moreover, it was found that the lipophilicity, thermostability and photostability of the enzymatic acylated blueberry pomace anthocyanins were improved compared with the untreated blueberry pomace anthocyanins. Cytotoxicity studies showed that acylated blueberry pomace anthocyanins inhibited tumor cells (HeLa, HepG2, and B16 cells) significantly and were less toxic to normal cells (L929 cells) at the maximum concentration (1000 µg/mL) and the longest duration of action (72 h). This study established a method for acylation of blueberry pomace anthocyanins that may be applied to other natural sources of anthocyanins. [Display omitted] • The blueberry pomace was used as the raw material for extracting anthocyanins. • Acylation of anthocyanins using Novozym 435 lipase. • Enzymatic acylation improves the stability of anthocyanins. • The effect of acetylated anthocyanins on cell proliferation was studied. [ABSTRACT FROM AUTHOR]

The asymmetric upper furnace configuration effect (mainly relied on the short upper furnace and large boiler nose) and unreasonable burner designs are taken as potential major factors that favoring the asymmetric combustion formation in down-fired boilers. To determine the boiler nose's role in this aspect and weaken the boiler nose's effect, two boiler nose's depth shrunk settings of C L = 0.199 and 0 were compared with the large design setup C L = 0.298 within a 600 MW e supercritical down-fired boiler. Numerical simulations on coal combustion were carried out for all three settings, plus full-load industrial-size measurements at the boiler's design setup. The boiler's design setup shows badly asymmetric combustion with poor burnout and high NO x emissions, corresponding to its reported, severely deflected gas/particle flow field. Shrinking boiler nose attains limited improvements (such as shortening the front/rear downward coal/air penetration difference, redirecting a little the upward gas flow towards the upper furnace central part, and shrinking the gas-flow stagnation zone below boiler nose), but unfortunately, essentially fails to change the flow-field deflection pattern and meanwhile decreases the gas fullness in the upper furnace's top zone to generate a potential threat on steam parameters. The absence of effective improvements in asymmetric combustion and apparently shortened flame penetration finally develop a worsened burnout, decreased O 2 at the furnace outlet, and lowered NO x emissions as C L decreased. Findings in this work thus exclude boiler nose as a potential major factor that favoring the formation of flow-field deflection and asymmetric combustion and meanwhile, provide useful information that under the circumstances with a short upper furnace aggravating the asymmetric upper furnace configuration effect, a relatively large boiler nose should be used for maintaining (i) the boiler nose's suppression effect on the upward gas flow and (ii) gas fullness in the upper furnace's top zone. [ABSTRACT FROM AUTHOR]

Mercury is a widespread toxicant in aquatic environment that can cause deleterious effects on fish. Although a number of mercury-regulated genes have been investigated in adult fish, the transcriptional responses of fish larvae to acute mercury exposure are not well understood. In this study, RNA sequencing was used to examine the transcriptional changes in developing zebrafish larvae under a low concentration of mercuric chloride exposure from 24 to 120 hpf. Our initial results showed that a total of 142.59 million raw reads were obtained from sequencing libraries and about 86% of the processed reads were mapped to the reference genome of zebrafish. Differential expression analysis identified 391 up- and 87 down-regulated genes. Gene ontology enrichment analysis revealed that most of the differential expressed genes are closely related to the regulation of cellular process, metabolic process, multicellular organismal process, biological regulation, pigmentation, and response to stimulus. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis demonstrated that antigen processing and presentation was the most significantly enriched pathway. Moreover, we characterized a novel and sensitive mercury-induced ABCB (ATP- binding cassette B subfamily) transporter gene - abcb5 . This gene is localized on zebrafish chromosome 16 and contains a 4014 bp open-reading frame. The deduced polypeptide is composed of 1337 amino acids and possesses most of functional domains and critical residues defined in human and mouse ABCB5/Abcb5. Functional analysis in vitro demonstrated that overexpression of zebrafish abcb5 gene can significantly decrease the cytotoxicity of mercury in LLC-PK1 cells, implying it is a potential efflux transporter of mercury. Thus, these findings provide useful insights to help further understand the transcriptional response and detoxification ability of zebrafish larvae following acute exposure to mercury. [ABSTRACT FROM AUTHOR]

Chinese horse bean-chili-paste (CHCP), a fermented condiment in China, is traditionally manufactured through naturally spontaneous semi-solid fermentation procedures without intentionally inoculated microorganisms. The aim of this study was to investigate the effect on microbiota and quality variations during CHCP fermentation by inoculation of selected autochthonous microorganisms Bacillus amyloliquefaciens and Candida versatilis. The results showed that relative abundance of Bacillus in the samples inoculated with B. amyloliquefaciens were increased from about 0.6% to almost 25%, and the batches bio-augmented with C. versatilis exhibited clearly 0.7 Lg copies/g higher biomass than that of the other samples. By bio-augmentation, six enzyme activities, namely acid protease, leucine aminopeptidase, α -amylase, cellulose, β -glucosidase and esterase, were considerably enhanced. As a result, inoculation of these two strains exhibited significant effect on the volatile profiles of CHCP. B. amyloliquefaciens herein was found to contribute mainly to the accumulation of acids, sulfur-containing compounds and pyrazines, whereas C. versatilis was considerably associated with the formation of alcohols, esters and phenols. This study proved that combination of B. amyloliquefaciens and C. versatilis could obtain more extensive aroma profiles, especially for the enrichment of miso -like and fruity flavors, which could provide a guideline for the tailored control of CHCP fermentation process. • B. amyloliquefaciens and C. versatilis could produce miso - and fruity-like aroma. • Microbial community dynamics were surveyed by qPCR and high-throughput sequencing. • B. amyloliquefaciens and C. versatilis remarkably enhanced six enzyme activities. • Combination of the two strains could complement each other for aroma formation. [ABSTRACT FROM AUTHOR]

Bacterial infections are among the leading causes of delayed wound healing. At present, a series of antibacterial materials, such as antibiotics, antimicrobial peptides (AMPs), metals and metal oxides (MMOs), have been used to fabricate antibacterial wound dressings. However, their translational potential is limited owing to their poor biocompatibility. ε-Polylysine (ε-PL) is a natural macromolecule with excellent biocompatibility and broad-spectrum antibacterial activity. Herein, ε-PL was incorporated into a cellulose/γ-polyglutamic acid (γ-PGA) composite hydrogel to form a novel double-network hydrogel termed as CGLH. The elastic modulus of CGLH increased from 0.097 ± 0.015 MPa to 0.441 ± 0.096 MPa, and the equilibrium swelling ratio increased from 382.7 ± 24.3 % to 611.2 ± 8.6 %. Several preclinical models were used to investigate the translational potential of this hydrogel. CGLH exhibited good biocompatibility and antibacterial activity, which promoted the healing of infected and critical-size wounds within 12 days. CGLH had positive effects on collagen synthesis, vascularization and cell proliferation. As a result, this study not only provided an effective alternative for wound healing but also proposed a double-network strategy for creating biocompatible and antibacterial biomaterials. [Display omitted] [ABSTRACT FROM AUTHOR]

• Converter vanadium slag was leached under atmospheric pressure without roasting. • Atmospheric sulfuric acid leaching of converter vanadium slag was optimized by RSM. • V leaching efficiency over 85% was achieved by direct atmospheric acid leaching. • Leaching process was governed both by surface chemical reaction and inner diffusion. Converter vanadium slag is an important kind of raw material for the production of vanadium products. Not only does the atmospheric acid leaching of vanadium from vanadium slag without roasting avoid the pollution of exhaust gas generated from roasting, but also it reduces the threat of Cr(VI) and V(V) and is conducive to the vanadium products preparation with low valence state. In this paper, the optimization of leaching conditions by response surface methodology and the direct sulfuric acid leaching kinetics of vanadium from converter vanadium slag were investigated. In the consequence of experiments, the optimum atmospheric sulfuric acid direct leaching conditions were initial sulfuric acid concentration of 4 mol/L, reaction temperature of 90 °C, reaction duration of 8 h and liquid to solid ratio of 8 mL/g with the particle size of vanadium slag below 20 μm. Under the optimum conditions, the vanadium leaching efficiency was 86.09%. The kinetics analysis demonstrated both the chemical reaction and inner diffusion were the control steps of the leaching process. The calculated apparent activation energy of the leaching process was 17.63 kJ/mol and the reaction order of sulfuric acid was 0.78. [ABSTRACT FROM AUTHOR]

Abstract Background Thyroid-stimulating hormone (TSH) plays a key role in maintaining normal thyroid function. Here, we used “big data” to analyze the effects of seasonality and temperature on TSH concentrations to understand factors affecting the reference interval. Methods Information from 339,985 patients at Peking Union Medical College Hospital was collected from September 1st, 2013, to August 31st, 2016, and retrospectively analyzed. A statistical method was used to exclude outliers, with data from 206,486 patients included in the final analysis. The research period was divided into four seasons according to the National Weather Service. Correlations between TSH concentrations and season and temperature were determined. Results Median TSH levels during spring, summer, autumn, and winter were 1.88, 1.86, 1.87, and 1.96 μIU/L, respectively. TSH fluctuation was larger in winter (±0.128) than in summer (±0.125). After normalizing the data from each year to the lowest TSH median value (summer), TSH appeared to peak in winter and trough in summer, showing a negative correlation with temperature. Pearson correlation analysis indicated that the monthly median TSH values were negatively correlated with temperature (r = −0.663, p <.001). Conclusions This study showed significant seasonal- and temperature-dependent variation in TSH concentrations. Thus, these might be important factors to consider when diagnosing thyroid function disorders. Highlights • “Big data” from clinical studies can be used to help establish reference intervals. • Season and temperature affect TSH levels, which are the highest in winter. • The gender differences may be a factor when establishing the TSH reference interval. [ABSTRACT FROM AUTHOR]

To clarify the understanding of the mechanism of bio-oil catalytic steam reforming, we selected acetic acid as a typical bio-oil model compound to study its detailed behavior in decomposition over an active stepped Ni surface by density functional theory calculations. The adsorption geometries and energies of various intermediates were reported. Linear correlations between the adsorption energy and the number of hydrogen atoms removed for CH x COOH, CH x COO, and CH x species ( x = 1–3) were found, with increments of −1.56, −0.81, and −1.80 eV, respectively. Thirty-seven possible elementary reactions of acetic acid decomposition were proposed, and their activation energies, reaction energies, rate constants, and equilibrium constants were calculated. Acetic acid dissociation likely started via α-carbon dehydrogenation, OH dehydrogenation, and dehydroxylation. Combined with microkinetic modeling, the most preferable decomposition pathway was suggested as CH 3 COOH → CH 3 CO → CO + CH 3 . The rate-determining step was CH 3 COOH dehydroxylation to CH 3 CO with an activation energy of 0.68 eV and a rate constant of 3.82 × 10 8 s −1 . The formation of CH 3 COO was dominant at high temperatures, whereas its decomposition occurred with difficulty. [ABSTRACT FROM AUTHOR]

The combustion behaviour of solid fuels – for example, coke and biomass char – is an important consideration in iron ore sintering as it determines heat availability for the melt formation process. This behaviour is influenced by the presence of an adhering layer of fine material around the fuel particles. In this study, analytical results for the combustion of single granulated fuel particles – applicable to all Thiele modulus ( ϕ h ) values – are presented. For the conversion of an isothermal carbon particle, the conversion parameter α is found to depend on ϕ h and the effectiveness factor η h . For ϕ h  < 9, α can be approximated by 0.4 η h , while for ϕ h  > 9, α approaches η h /3. The relationship between α and η h is not altered by the presence of an adhering layer. However, at high temperatures and for reactive fuels, an adhering layer influences the combustion rate significantly. The fuel combustion process in iron ore sintering can be viewed as occurring in three regimes depending on factors such as fuel size, reactivity and temperature. To investigate the effect of fuel properties on sintering performance, the developed combustion model is integrated into a 2D iron ore sintering model. Good comparisons are obtained between model results and experimental data from laboratory sintering tests. In the study of fuel types, model results indicate that when biomass char replaced coke there was significant lowering of flame front temperature and combustion efficiency, while the speed of the flame front down the bed accelerated. These changes can be explained by the higher reactivity of the biomass char and its physical properties which influence the granulation process – resulting in changes in the thickness of the adhering layer and combustion behaviour. The flow-on effect of this on sintering performance is consistent with reported experimental results by other researchers. [ABSTRACT FROM AUTHOR]

Objectives EGFR mutation is a key factor to predict EGFR-TKI efficacy. However, a significant number of advanced patients do not have sufficient tumor specimens for molecular testing. Also, there is a lack of quantitative assay to analyze the mutant abundance. This study aims to evaluate the detection efficiency and clinical feasibility of a new platform, namely ARMS-Plus, for the detection and quantification of EGFR mutations in plasma. Materials and methods The detection limit of ARMS-Plus was assessed by detecting spiked mutant plasmids which were serially diluted with normal human genomic DNA. The cutoff values were defined by examining the mutant copy numbers presented in 134 healthy controls. Plasma samples from 65 lung cancer patients were collected to evaluate the clinical performance of ARMS-Plus. EGFR mutations were concurrently tested by droplet digital PCR (ddPCR) for the plasma samples and conventional amplification refractory mutation system-PCR (ARMS-PCR) for the matched tumor tissue specimens to serve as a standard for comparison. Results In this study, the analytical sensitivity of ARMS-Plus was 0.015%. The cutoff values of EGFR 19Del, L858R, T790 M mutations were defined as 2, 5, and 3 copies/mL, respectively. With tumor specimens as the standard, the sensitivity, specificity, and concordance rate of ARMS-Plus and ddPCR were 60.7%, 94.6%, and 80.0%; and 50.0%, 97.3%, and 76.9%, respectively. For quantification, the plasma 19Del and L858R mutant abundance detected by ARMS-Plus and ddPCR were consistent (Spearman R = 0.7956 and 0.7710, P < 0.0001). Conclusion ARMS-Plus is a reliable, convenient and cost-effective method for the detection and quantification of plasma EGFR mutations. [ABSTRACT FROM AUTHOR]

Solvent effects on the decomposition of formic acid over a Co(111) surface were studied via density functional theory calculations combined with a continuum implicit solvation model. The solvents used here were water, methanol, and acetone. The adsorption energies of key intermediates, the activation barriers and the rate and equilibrium constants of various elementary reactions in vacuum and in the solvents were obtained. Solvent presences decrease the adsorption energies of species. Formic acid decomposition on the surface goes through HCOO rather than COOH both in vacuum and in the solvents. The most favorable decomposition pathways in vacuum and in acetone are HCOOH → HCOO → HCO → CO. The corresponding rate determining steps are HCOO deoxidation to HCO with activation barriers of 0.78 and 0.76 eV, respectively. In the presences of water and methanol, the preferred pathways are shifted to HCOOH → HCOO → HCOO- m → CO 2 below 750–800 K. Above those temperatures, the path of HCOOH → HCOO → HCO → CO becomes dominant again. [ABSTRACT FROM AUTHOR]

A new system integrating geothermal energy into post-combustion carbon capture is proposed in this paper. Geothermal energy at medium temperatures is used to provide the required thermal heat for solvent regeneration. The performance of this system is compared with solar assisted carbon capture plant via technical and economic evaluation. A 300 MWe coal-fired power plant is selected as the reference case, and two different locations based on the local climatic conditions and geothermal resources are chosen for the comparison. The results show that the geothermal assisted post-combustion carbon capture plant has better performances than the solar assisted one in term of the net power output and annual electricity generation. The net plant average efficiency based on lower heating value can be increased by 2.75% with a thermal load fraction of about 41%. Results of economic assessment show that the proposed geothermal assisted post-combustion carbon capture system has lower levelized costs of electricity and cost of carbon dioxide avoidance compared to the solar assisted post-combustion carbon capture plant. In order to achieve comparative advantages over the reference post-combustion carbon capture plant in both locations, the price of solar collector has to be lower than 70 USD/m 2 , and the drilling depth of the geothermal well shall be less than 2.1 km. [ABSTRACT FROM AUTHOR]

To elucidate bio-oil catalytic reforming mechanisms, acetic acid has been selected as a model compound to carry out density functional theory calculations on its decomposition pathways over an active Co stepped surface. The adsorption energies and stable geometries of the reactant and important reaction intermediates have been obtained. Preferential adsorption on a step as opposed to a flat surface has been discerned. The activation barriers and reaction enthalpies for various elementary reactions involved in acetic acid decomposition have also been obtained. Four likely parallel decomposition pathways with activation barriers of less than 0.9 eV have been identified. The most kinetically favorable decomposition pathway is CH 3 COOH → CH 3 CO → CH 2 CO → CH 2 → CH. The rate-determining step is CH 3 CO dehydrogenation, with a reaction barrier of 0.52 eV. In addition, the formation and primary decomposition pathways of the critical intermediate acetone have also been investigated. [ABSTRACT FROM AUTHOR]

Abstract: Mutations in the ceramide kinase-like gene (CERKL) are associated with severe retinal degeneration. However, the exact function of the encoded protein (CERKL) remains unknown. Here we show that CERKL interacts with mitochondrial thioredoxin 2 (TRX2) and maintains TRX2 in the reduced redox state. Overexpression of CERKL protects cells from apoptosis under oxidative stress, whereas suppressing CERKL renders cells more sensitive to oxidative stress. In zebrafish, CERKL protein prominently locates in the outer segment and inner segment of the photoreceptor of the retina. Knockdown of CERKL in the zebrafish leads to an increase of retinal cell death, including cone and rod photoreceptor degeneration. Signs of oxidative damage to macromolecules were also detected in CERKL deficient zebrafish retina. Our results show that CERKL interacts with TRX2 and plays a novel key role in the regulation of the TRX2 antioxidant pathway and, for the first time, provides an explanation of how mutations in CERKL may lead to retinal cell death. [Copyright &y& Elsevier]

Abstract: In a gas/particle two-phase testing facility with the use of a three-component particle-dynamics anemometer, we determine the influence of secondary air mass flow rates on gas/particle flow characteristics in the near-burner region of a centrally fuel-rich swirl coal combustion burner. Velocities, particle volume flux profiles and normalized particle number concentrations were obtained. The peaks of axial, radial, and tangential mean velocities and root mean square velocities increase as the secondary air mass flow rate increases. Simultaneously, the recirculation zone enlarges accompanied by an increase in swirl number. The peak particle volume flux near the chamber axis, between axial distance x/d = 0.1–0.7, increases with secondary air mass flow rate although its peak value decreases and the attenuation rate falls faster than other mass flow rates. [Copyright &y& Elsevier]