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In recent years, marine hydrate has attracted more and more attentions. As a creative way to efficiently exploit marine hydrate, the method of solid fluidization exploitation is to excavate and crush hydrate, transport hydrate particles to sea surface platform through airtight pipeline, and obtain methane gas finally. When hydrate particles are transported up, as temperature rises and pressure drops, hydrate will decompose at a certain critical position and produce a large amount of gas, bringing complicated gas‐liquid‐solid multiphase non equilibrium pipe flow, and seriously threating well control securities. Thus, we establish mathematical models of wellbore temperature and pressure, hydrate phase equilibrium, hydrate dynamic decomposition in riser pipe flow and wellbore multiphase flow coupling hydrate dynamic decomposition, and propose and verify numerical calculation method. Then numerical model application analysis under different construction parameters is carried out, influence behaviors of multiphase non equilibrium pipe flow are obtained, and field construction measures are put forward. Properly increasing solid throughput can increase production of natural gas. However, problems such as well control risks will intensify. Therefore, delivery capacity, liquid density, and wellhead back pressure should be increased appropriately at the same time. This study provides important technical support for solid fluidization exploitation of marine hydrate. Physical model and system mathematical models are established to demonstrate multiphase non equilibrium pipe flow in hydrate solid fluidization exploitation of marine natural gas hydrate. Numerical calculation methods for multiphase non equilibrium pipe flow is developed and verified. Numerical model is applied to analyze and obtain the multiphase non equilibrium flow behaviors in hydrate solid fluidization exploitation. [ABSTRACT FROM AUTHOR]

Because the excessive apoptosis of articular chondrocytes contributes to extracellular matrix (ECM) loss and cartilage damage in rheumatoid arthritis (RA), inhibiting chondrocyte apoptosis might be a promising strategy for RA. Aquaporin1 (AQP1) is overexpressed in RA cartilage and synovial tissues, and play a vital pathogenic role in RA development. Particularly, we previously reported that acetazolamide (AZ) as an AQP1 inhibitor suppressed secondary inflammation and promoted ECM production in cartilage of adjuvant-induced arthritis rats. Here, we investigated the antiapoptotic effect of AZ on interleukin-1β (IL-1β)-induced apoptosis, a classic in vitro model of chondrocyte apoptosis. AZ treatment could inhibit IL-1β-induced apoptosis, evidenced by increasing cell viability, relieving apoptotic nuclear morphology, decreasing apoptosis rates, and restoring mitochondrial membrane potential. Additionally, AZ reversed IL-1β-induced decrease of Bcl-2 protein and reduced IL-1β-induced increases of Bax and caspase 3 protein, accompanied by inhibiting IκBα degradation and phosphorylation in cytoplasm, reducing NF-κB p65 protein level in nucleus and preventing NF-κB p65 translocation from cytoplasm to nucleus. In conclusion, our findings indicated that AZ could effectively attenuate IL-1β-induced chondrocyte apoptosis mediated by regulating the protein levels of apoptosis-related genes and inhibiting the activation of NF-κB signal pathway, suggesting that AZ might be of potential clinical interest in RA treatment. [ABSTRACT FROM AUTHOR]

This research examined philanthropy ad messages in terms of four key elements: philanthropy goal, beneficiary, expected fundraising impact, and how the suggested donation is appraised. A content analysis was carried out to systematically study ad messages from nonprofit organizations on the Philanthropy 400 list. Specifically, the frequency of appearance of each type of message elements was analyzed in terms of four theoretical concepts: regulatory focus (promotion vs. prevention goal), egoism/altruism (self vs. others as beneficiary), temporal orientation (present vs. future fundraising impact), and efficacy appraisal (self- vs. response-efficacy in how a donation is appraised). Since past research further suggests that persuasion may be enhanced when message elements are well matched in terms of “compatible fits,” this study further analyzed how the four message elements were combined in usage. The findings of this research show that while most nonprofit organizations actively utilized all four types of elements in their messages, the current practice did not follow the guidelines as would be suggested by compatible fits literature. In this respect, more research is needed to understand the discrepancy and provide better guidelines for future communication strategies in the nonprofit sector. [ABSTRACT FROM AUTHOR]

Hydrogen production from vegetable oil via a chemical looping process with hematite oxygen carriers has been carried out in a fixed-bed reactor at 1023.15–1173.15 K. The lattice oxygen release process and crystalline transformation for the oxygen carrier in the reaction process are investigated. Results indicate that the maximum H 2 composition achieved in the chemical looping hydrogen stage is over 91.72% when hematite oxygen carriers consisting of Fe 2 O 3 , Al 2 O 3 and SiO 2 are used. The active component Fe 2 O 3 in oxygen carriers represents three reduced peaks corresponding to the crystalline form transition from Fe 2 O 3 to Fe 3 O 4 . Up to 96.13% of the lattice oxygen in Fe 2 O 3 can be consumed in the reduction process. The deep reduction of FeO to Fe represents a lower reaction rate with the exhaustion of the lattice. The maximum carbon conversion efficiency of vegetable oil of 79.10% when the ratio of water to oil is 1.2 and hydrogen-rich gas with a highest concentration of 91.72% are achieved in the chemical looping reforming stage and H 2 production stage, respectively. The impurities in the gas are ascribed to the carbon deposition and steam reaction in the chemical looping process. The micrographs of fresh and used oxygen carriers present irregular and blocky structures, sintering is not observed after the multi-cycle reaction process. The crystalline form and reaction activity remain stable after 20-cycle experiments, suggesting that the hematite oxygen carrier is a promising candidate for hydrogen generation from vegetable oil via the chemical looping process. [ABSTRACT FROM AUTHOR]

Recently, gut flora has been linked to the onset of obesity and has been shown to influence the host's metabolism. Acupuncture is a well-known agent used for the treatment of numerous diseases such as obesity. This study aimed to explore the impacts of electroacupuncture treatment on gut microbiota composition and function in obese mice. Pyrosequencing of 16S rRNA genes and Metagenomic analysis of the fecal microbiota were used for this purpose. The basic parameters of body weight, Lee's index, serum lipid and epididymal adipose weight were ameliorated significantly after introducing an electroacupuncture intervention. Acidobacteria, Cyanobacteria and Basidiomycota (Normal group) and Fusobacteria, Firmicutes and Spirochmycetes (Model group) were remarkably affluent at the phylum level. Bacteroides sp. CAG: 927 and Prevotella sp. CAG: 1031 (Normal group), Lachnospiraceae bacterium and Helicobacter rodentium (Model group) at the species level were distinctly enriched. The structures and functions of the intestinal flora were significantly different between healthy and obese mice, and animals in the acupuncture group gradually tended towards healthy controls. Moreover, electroacupuncture altered the bacterial diversity and metabolic genes to establish new balance, observed the obvious change from 7 d and stabilized gradually through 21 d. These findings suggested gut flora could be a novel target of electroacupuncture treatment against obesity. [ABSTRACT FROM AUTHOR]

Turnovers of sex-determining systems represent important diversifying forces across eukaryotes. Shifts in sex chromosomes—but conservation of the master sex-determining genes—characterize distantly related animal lineages. Yet in plants, in which separate sexes have evolved repeatedly and sex chromosomes are typically homomorphic, we do not know whether such translocations drive sex-chromosome turnovers within closely related taxonomic groups. This phenomenon can only be demonstrated by identifying sex-associated nucleotide sequences, still largely unknown in plants. The wild North American octoploid strawberries (Fragaria) exhibit separate sexes (dioecy) with homomorphic, female heterogametic (ZW) inheritance, yet sex maps to three different chromosomes in different taxa. To characterize these turnovers, we identified sequences unique to females and assembled their reads into contigs. For most octoploid Fragaria taxa, a short (13 kb) sequence was observed in all females and never in males, implicating it as the sex-determining region (SDR). This female-specific “SDR cassette” contains both a gene with a known role in fruit and pollen production and a novel retrogene absent on Z and autosomal chromosomes. Phylogenetic comparison of SDR cassettes revealed three clades and a history of repeated translocation. Remarkably, the translocations can be ordered temporally due to the capture of adjacent sequence with each successive move. The accumulation of the “souvenir” sequence—and the resultant expansion of the hemizygous SDR over time—could have been adaptive by locking genes into linkage with sex. Terminal inverted repeats at the insertion borders suggest a means of movement. To our knowledge, this is the first plant SDR shown to be translocated, and it suggests a new mechanism (“move-lock-grow”) for expansion and diversification of incipient sex chromosomes. [ABSTRACT FROM AUTHOR]

Cancer metastasis has been a major impediment to effective cancer treatment and is the major cause of cancer-related death. Polyphenols compounds have been reported to possess anti-metastasis activity through their inhibitory activity of matrix metalloproteinases (MMPs). In this paper, twelve polyphenols compounds, including three novel phenols, named selaphenins A–C ( 1 – 3 ), two known selaginellin derivatives ( 4 and 5 ), together with seven known biflavonoids ( 6 – 12 ) were isolated from the plant of Selaginella tamariscina . Their structures were elucidated by extensive spectroscopic analyses. Notably, polyphenols compound 10 suppressed the migration of A549 cells by primary targeting MMP-9. The antitumor activity of compound 10 was possibly due to the induction of cell apoptosis through intrinsic apoptosis pathways, accompanied by increasing the expression of Bax and caspase-3 in a dose-dependent manner. This study provides evidence that polyphenols analogues from S. tamariscina as inhibitors of MMP-9 exhibited potential migration inhibition activities. [ABSTRACT FROM AUTHOR]

C35H32N6O2, triclinic, P1 (no. 2), a = 10.902(2) Å, b = 12.434(2) Å, c = 13.481(4) Å, α = 102.881(5)°, β = 104.935(5)°, γ = 114.542(3)°, V = 1488.6(6) Å3, Z = 2, Rgt(F) = 0.0511, wRref(F2) = 0.1429, T = 296 K. [ABSTRACT FROM AUTHOR]

C31H29N3O7, monoclinic, P21/c (no. 14), a = 13.6280(14) Å, b = 14.4801(15) Å, c = 14.4962(15) Å, β = 97.586(2)°, V = 2835.6(5) Å3, Z = 4 Rgt(F) = 0.0532, wRref(F2) = 0.1569, T = 296 K. [ABSTRACT FROM AUTHOR]

• A lysosome-targeting probe has been developed based on pyrrole-tricyanofuran. • The probe shows AIE behavior in almost pure aqueous media. • The probe can detect HSO 3 − and viscosity on fluorescence and UV−Vis spectra. • The probe can image lysosomal HSO 3 − and viscosity in cells and zebrafish. A novel AIE active bifunctional probe for detecting bisulfite (HSO 3 −) and viscosity synchronously was developed based on pyrrole-tricyanofuran skeleton. This probe exhibited aggregation-induced emission behavior in almost pure aqueous media, and responded to HSO 3 − with a "turn-off" signal and viscosity changes with a "turn-on" signal in semi-aqueous solutions, respectively. The response mechanism of the probe associated with HSO 3 −-involving C C breakage was demonstrated via ESI-MS, 1H NMR analysis, and density functional theory calculations. Furthermore, the probe has been applied to imaging endogenous HSO 3 − and viscosity changes in the lysosomes of C6 cells and zebrafish. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrogen-doped carbon nanotubes modified ultrafiltration membrane coupled with PMS activation. • Efficient degradation and transformation of EDTMP could be realized rapidly. • The coupled system demonstrated remarkable anti-fouling and water purification capability. • The surface-bound SO 4 •−/•OH was proposed to be the major reactive species. The nitrogen-doping carbon nanotube modified polyethersulfone membrane (NCNT@PES) was prepared by vacuum-assisted filtration. The catalytic activity and anti-fouling capacity of NCNT@PES/peroxymonosulfate (PMS) system were both systematically investigated. Selecting ethylenediamine tetra(methylene phosphonic acid) (EDTMP) as a target phosphonate, the NCNT@PES/PMS system degraded almost 100% of EDTMP, and about 60% of the total phosphorus (TP) in EDTMP could be transformed into orthophosphate (PO 4 3−) within 1 min. Scavenger experiments and electron paramagnetic resonance (EPR) technique verified that the surface-bound radicals were mainly contributed the degradation and transformation of EDTMP in the NCNT@PES/PMS system. The presence of HCO 3 −, SO 4 2− and NOM weakened the catalytic reactions, nevertheless, the NCNT@PES/PMS system still showed considerable effectiveness on the transformation of EDTMP in real sewage effluent. Moreover, the anti-fouling experiment proved that NCNT@PES/PMS system were superior on the removal of fluorescent components in the real sewage effluent, and their removal rates for the dissolved organic matter (DOC) and UV absorbance at 254 nm (UV 254) were also improved. During the filtration cycles, the NCNT@PES/PMS system mitigated the membrane fouling significantly, which had been verified by the slower decline of normalized flux, less ultrapure water flux loss rates and higher ultrapure water flux recovery rates. This study provided a novel but simple way for effective EDTMP decontamination, at the same time, confirmed the potential of NCNT@PES membrane coupled with PMS activation on anti-fouling and water purification ability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ratiometric probe for detecting pH, HSO 3 − and viscosity in the mitochondria was developed. • Probe 1 exhibited rapid response, large Stokes shift, good optical performance, high selectivity, and high sensitivity in solution. • Multifunctional-detection in the mitochondria of C6 cells and zebrafish. • Detection can be achieved using a smartphone with a chromaticity APP. pH, HSO 3 −, and viscosity are crucial bio-markers for evaluating the status of mitochondria in the cell micro-environment. With this research, we developed a ratiometric mitochondria-targeting fluorescent probe 1 that was responsive toward bisulphite, pH and viscosity. Hydroxylphenyl 1,3-benzoxazole (D) acted as a pH recognition unit; benzo[ e ]indolium (A) acted as a fluorescent rotor to achieve a viscosity response; the C = C bond constructed by bridging D and A was susceptible to nucleophilic attack and hence responded to HSO 3 −. Probe 1 exhibits significant ratiometric signal changes, high sensitivity, outstanding selectivity, and good stability for detecting pH, viscosity, and SO 2 in solution. Probe 1 was used for imaging pH, viscosity, and SO 2 derivatives in live cells and zebrafish, indicating its potential for identifying mitochondrial dysfunctions. [ABSTRACT FROM AUTHOR]

The gas explosion induced by the high-temperature surface of coal spontaneous combustion in goaf will cause a devastating blow to personnel and equipment in the process of coal mining. Secondary explosion may be induced by the high-temperature surface of coal spontaneous combustion after primary explosion with the continuous emission of gas and the ventilation of goaf. This will lead to new disasters for the ongoingrescue operation. A high-temperature source explosion experimental system consistent with the similarity and unity of goaf was designed and developed based on the similarity criterion in this study. A CH4/air explosion experiment was carried out with the high-temperature surface as an ignition source. The characteristics of secondary explosion were studied, and chemical kinetics was analyzed. It is of great significance to the safety of the process of mining production. The results show that the secondary explosion limit (6.5–14%) is less than the primary explosion (5.5–14.5%). Its explosion risk (F) is reduced by 15.6%. The key parameters Pmax, Tmax, and (dP/dt)max of secondary explosion at each concentration are lower than those of primary explosion. The te of secondary explosion is higher than primary explosion. The most dangerous concentration of primary and secondary explosions induced by the high-temperature surface is 11.5%. Carbon oxides (CO2 and CO) and C2 hydrocarbon gases (C2H2, C2H4, and C2H6) are generated after primary explosion. The chemical kinetics of secondary explosion was analyzed with CHEMKIN Pro 2021. When the CH4 concentration is <11.5%, the formation of the key free radicals ·H, ·O, ·OH, and CH2O is inhibited due to the formation of CO2. When the CH4 concentration is ≥11.5%, the formation of the key free radicals ·H, ·O, ·OH, and CH2O is inhibited due to the generation of combustible gases (C2H2, C2H4, C2H6, and CO) and inert gas (CO2). As a result, the limit range of secondary explosion and the explosion hazard characteristics are reduced. R156 and R158 played major roles in the process of secondary explosion with the analysis of reaction sensitivity. [ABSTRACT FROM AUTHOR]

An inorganic–organic hybrid probe MP-ZIF-90 was synthesized via a simple condensation reaction based on the free CHO groups of zeolitic imidazolate framework-90 (ZIF-90) and 4-methyl-1-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)pyridinium bromide (MP). This probe exhibited intense green emission, which was selectively quenched by the addition of ClO− anions. The response of probe MP-ZIF-90 toward ClO− was rapid (within 20 s) and sensitive, with a limit of detection (LOD) of 0.612 μM. Importantly, the utilization of the probe in the fluorescence imaging of ClO− anions in the mitochondria of living cells and zebrafish was demonstrated. [ABSTRACT FROM AUTHOR]

The application of polysaccharide-based coatings to prolong the shelf-life of fruits has attracted increasing attention. This study aims to develop a fruit coating comprising locust bean gum/carboxycellulose nanocrystals/ZnO (LCZ) blended with bayberry tannins (BT). The results revealed a significant increase from 4.89% and 11.04% to 29.92% and 45.01% in the free radical scavenging rates of 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-di-[3-ethylbenzthiazthiazoline sulfonate] with the percentage of BT increasing from 0% to 5%, respectively. At a 5% of BT, the antibacterial activity against both E.coli and S. aureus exceeded 90% while simultaneously achieving excellent UV shielding (transmittance of 380–200 nm ≤ 0.19%). After 3 days of storage, uncoated bananas showed signs of browning, and their titratable acid and vitamin C (Vc) contents decreased from 0.57% to 0.30% and from 7.37 mg/100 g to 4.77 mg/100 g, respectively. However, bananas coated with LCZ containing 3% BT not only exhibited a better appearance, but also possessed higher titratable acid (0.44%) and Vc content (5.31 mg/100 g). This study provides a sustainable and multifunctional coating for fruit preservation. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease (PD) is seriously threatening the health and life quality of the elderly, who have a high incidence and high disability rate. Resveratrol (RES) was reported to play a protective role in PD. However, the functions and potential mechanism of RES in PD remain unclear, which need to be further explored. Methods: Human neuroblastoma cells (SH-SY5Y and SK-N-SH) were subjected to 1-Methyl-4-phenylpyridium (MPP+) induction to construct a cell model of PD. Cell viability was evaluated using CCK-8. The gene expression was evaluated using qRT-PCR and western blot. Luciferase activity assay and RIP were performed to validate interactions among SNHG1, miR-128-3p and SNCA. Results: Our results exhibited that RES reduced SNHG1 and SNCA expression but elevated miR-128-3p expression in human neuroblastoma cells upon MPP+ induction. Functionally, RES resulted in the promotion of cell autophagy in MPP+-induced human neuroblastoma cells, while these influences were abolished by SNHG1 overexpression. Mechanistically, SNHG1 could indirectly elevate SNCA expression via sponging miR-128-3p. Moreover, SNCA overexpression reversed SNHG1 silencing-induced cell autophagy in MPP+-induced human neuroblastoma cells upon RES pre-incubation. Conclusions: RES prevented MPP+-induced repression of cell autophagy through inhibiting the SNHG1/miR-128-3p/SNCA axis, suggesting that RES might play a preventive effect on PD progression. [ABSTRACT FROM AUTHOR]

C20H19N3O, orthorhombic, P212121 (no. 19), a = 5.8776(10) Å, b = 7.6503(13) Å, c = 36.447(6) Å, V = 1638.8(5) Å3, Z = 4, Rgt (F) = 0.0374, wRref (F 2) = 0.0950, T = 296 K. [ABSTRACT FROM AUTHOR]

C30H34N8O4S2Cu, triclinic, P1̄ (no. 2), a = 12.9537(9) Å, b = 15.2802(10) Å, c = 17.1041(11) Å, α = 78.748(1)°, β = 79.684(1)°, γ = 79.270(1)°, V = 3226.4(4) Å3, Z = 4, Rgt(F) = 0.0488, wRref(F2) = 0.1178, T = 296 K. [ABSTRACT FROM AUTHOR]

C41H41N9O5Co, monoclinic, P21/n (no. 14), a = 10.666(4) Å, b = 18.538(6) Å, c = 19.585(7) Å, β = 104.036(7)°, V = 3757(2) Å3, Z = 4, Rgt(F) = 0.0420, wRref(F2) = 0.1062, T = 296 K. [ABSTRACT FROM AUTHOR]

Background: Cannulated screws (4.0 mm) provide inter-fragmentary compression and stability to fractures. A guide wire is used to define the screw trajectory and hold the fracture fragment while the screw is being inserted. The cannulated shaft typically accommodates a 1.25 mm guide pin. Since the guide pin is very slender and undergoes elastic deformation during insertion, there is a high probability of pin breakage.Methods: The authors have devised a new way to place the 4.0 mm cannulated screws in a manner that prevents the intraoperative complication of guide wire breakage. For this technique, predrilling was achieved using a 2.0 mm K-wire which was subsequently replaced with a 1.25 mm guide pin under the protection of sleeve. 4.0 mm cannulated screws were then inserted into a defined trajectory over the guide pin.Results: Using the technique, over 20 patients were managed in our department over a period of two years without any complications.Conclusion: We have observed that patients treated with this method experience short operation time, combined with good clinical outcome and we recommend its use in cases where cannulated screw use is warranted. [ABSTRACT FROM AUTHOR]

The influence of oceanographic processes on phytoplankton diversity and community structure was examined during a cruise conducted from July to August 2012 in the northern South China Sea (nSCS). One hundred ninety seven seawater samples were collected and analyzed from 41 stations in the nSCS. A total of 215 species were identified belonging to 67 genera, mostly dominated by diatoms (67.36%) followed by dinoflagellates (28.16%). The mean cell abundance of diatoms and dinoflagellates were 1.954 × 10 3 cells L −1 and 0.817 × 10 3 cells L −1 , respectively. Diatoms mainly distributed in coastal region whereas dianoflaglletes in the open sea. Margalaf's species richness ( d Ma ) was maximum (3.96) at SQD1 station (Depth 15 m), whereas it was minimum (0.07) at SS1 (Depth 200 m). Further, Box-Whisker plot displayed that dissolved inorganic nutrients incresed with depth. Nevertheless, redundacy analysis reveled that phytoplankton density has a negative relationship with nutrients. Overall the presesant study provides latest in-depth information about how the factors influencing the phytoplankton density and diversity in the (nSCS) during summer based on the cruise data which could serve as a reference for the similar study. [ABSTRACT FROM AUTHOR]

A novel ‘D-π-A’ sensor 1 has been designed and prepared via the condensation reaction of 3‑ethyl‑2‑methyl‑1,3‑benzothiazol‑3‑ium iodide and 5‑nitro‑ o ‑vanillin. Upon treatment with cyanide, sensor 1 exhibited a significant near-infrared (NIR) fluorescence quenching at 663 nm. The MS, IR, 1 H NMR and DFT methods confirmed that the response of 1 to cyanide is due to the nucleophilic addition reaction, which results in the inhibition of the Intramolecular Charge Transfer (ICT) process in the sensor. Furthermore, sensor 1 was used for the determination of CN − in HeLa cells. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to compare the effect of two educational interventions on the psychosocial well-being of Hong Kong Chinese women who have a positive high-risk human papillomavirus (HPV) test and normal cervical cytology.Methods: Participants were randomised into either leaflet group, in which a written HPV factsheet was provided; or counselling group, in which a didactic HPV presentation in person in addition to the factsheet was provided. Women's psychological conditions were assessed by self-administered questionnaires at pre, post (within one week) and 6 months after the educational interventions. Main outcome measures were psychosocial well-being (cervical cancer worry, anxiety and depression, screening-related anxieties, HPV-related shame) and knowledge of cervical screening and HPV.Results: Data from 121 women (52 in leaflet group; 69 in counselling group) were analysed. There was no significant difference in the psychosocial well-being between the two groups at alltime points. Irrespective of the two educational interventions, cervical cancer worry and anxiety decreased over time. The counselling group had a significantly higher score in knowledge of cervical screening and HPV compared with leaflet group (mean score 4.65 ± 0.19 versus 3.71 ± 0.23, p = 0.002) at post-educational intervention, but there was no significant difference (mean score 4.14 ± 0.22 versus 3.58 ± 0.24, p = 0.084) at 6 months.Discussion: Both educational interventions were comparable in relieving adverse HPV-related psychosocial effects. Combination of counselling and leaflet were more effective than leaflet only in improving women's knowledge on cervical screening and HPV soon after educational interventions but the benefit was not apparent after 6 months. [ABSTRACT FROM AUTHOR]

Stroke-induced immune suppression predisposes the host to infections and can contribute to high morbidity and mortality in stroke patients. Because ischemic stroke has a profound effect on the systemic immune response, which may explain the increased susceptibility of stroke patients to infection, an urgent need persists for a better understanding of mechanisms associated with immune suppression; new and effective treatments for stroke can then be identified. NK cells play a key role in early host defense against pathogens by killing infected cells and/or producing cytokines such as IFN-γ. Because the phenotype and function of peripheral NK cells have been widely investigated in ischemic stroke, nCounter Inflammation Gene Array Analysis was used to build immune-related gene profiles of NK cells to comprehensively analyze the molecular signature of NK cells after ischemic brain injury. We observed distinct gene expression profiles reflecting different splenic NK-cell phenotypes and functional properties across the time course of transient middle cerebral artery occlusion (MCAO). Based on gene expression and pathway-network analysis, lower expression levels of signal transducer and activator of transcription-3 (STAT3) were observed in animals with MCAO compared with sham control animals. Genetic activation of STAT3 through the introduction of STAT3 clustered regularly interspaced short palindromic repeats (CRISPR) plasmid prevented the loss of NK-cell-derived IFN-γ production after MCAO, together with reduced bacterial burden and mortality. Our data suggest that brain ischemia impairs NK-cell-mediated immune defense in the periphery, at least in part through the JAK-STAT3 pathway, which can be readdressed by modulating STAT3 activation status. [ABSTRACT FROM AUTHOR]

A novel pyrene-based Schiff base derivative, 1 , was synthesized by one-pot reaction. This compound was then used for aggregation emission enhancement and as fluorescence turn-on sensor toward Cu 2+ in semi-aqueous solution based on metal-induced self-assembly. Detection limit of Cu 2+ ion was 35 nM. The fluorescent sensor was further applied in monitoring intracellular Cu 2+ in HeLa cells. [ABSTRACT FROM AUTHOR]

Objectives: Previous studies have shown that aquaporin 1 (AQP1) is up-regulated in synovium and cartilage of rheumatoid arthritis (RA) patients and that AQP1 may be involved in joint swelling and synovial inflammation. This study was aimed to investigate the potential therapeutic effect of acetazolamide (AZ, an AQP1 inhibitor) on rat adjuvant-induced arthritis (AIA) and explore its related mechanisms. Materials and methods: Rat AIA was induced by complete Freund’s adjuvant. The effect of AZ on rat AIA was evaluated by secondary hind paw swelling, arthritis index, TNF-α and IL-1β serum levels and histological examination of ankle joint. Proteoglycans expression and mRNA levels of type-II collagen (COII) and aggrecan in cartilage were measured by alcian blue staining and real-time PCR, respectively. The protein levels of AQP1, IκBα, phospho-IκBα (p-IκBα), NF-κB p65 and phospho-NF-κB p65 (p-NF-κB p65) in synovial tissues were detected by western blot. Results: AZ treatment could inhibit secondary hind paw swelling and arthritis index, reduce serum levels of TNF-α and IL-1β, and ameliorate pathological changes of ankle joint in AIA rats. AZ increased proteoglycans production and mRNA levels of COII and aggrecan in cartilage tissues. Moreover, AZ decreased AQP1 protein level and suppressed the activation of NF-κB pathway in synovium, indicated by inhibiting the degradation and phosphorylation of IκBα and reducing p-NF-κB p65 protein level. Conclusions: AZ as an AQP1 inhibitor has a powerful therapeutic effect on rat AIA via inhibiting NF-κB activation, suggesting AQP1 inhibition might be of potential clinical interest in RA treatment. [ABSTRACT FROM AUTHOR]

A well-designed heterostructure engineered ZnIn 2 S 4 nanosheet/TiO 2 nanowire arrays photoanode is investigated for photocathodic protection. The ZnIn 2 S 4 nanosheets are distributed uniformly on the surface of the TiO 2 nanowire by a hydrothermal method. The stem-and-leaf-like ZnIn 2 S 4 nanosheet/TiO 2 nanowire arrays exhibit excellent photoelectrochemical properties, owing to the energy band structure and large surface area. A maximum photocurrent density of 2 mA cm −2 is achieved for the ZnIn 2 S 4 nanosheet/TiO 2 nanowire composite film for a 6 h reaction time under white illumination. Moreover, the potential of the 304 stainless steel coupled with the composite film immediately shifts negatively to −1.17 V (vs. SCE), which is significantly lower than the corrosion potential (−0.201 V vs. SCE). Thus, the composite film offers a superior photocathodic protection for stainless steel against corrosion by a NaCl solution. This study provides a promising approach for the design and synthesis of composite films with enhanced photoelectrochemical performance. [ABSTRACT FROM AUTHOR]

Abstract: Host plants will affect the performance and population dynamics of the polyphagous insect pest Grapholitha molesta (Busck) (Lepidoptera: Tortricidae). Cultivar‐level variability needs to be considered in assessing the performance of G. molesta. We evaluated the fitness of G. molesta on five apple varieties in the laboratory by placing eggs on apples and observing their performance including survival, development, and fecundity of the adult insect. Our results demonstrated differences between indices such as larval duration, pupal weight, egg production, length of tunnel, and exiting rate of larvae, which gave similar host rankings. Variety Danxia was less suitable than Jinqing and Shuohong, and more suitable than Empire and Jinxing. However, other indices such as pupal duration, total pre‐oviposition time, and the estimated population parameters resulted in a different host ranking. We calculated weighted fitness scores to overcome the problem of inconsistent rankings. Empire changed from being the second highest ranking variety based on all population parameters to the second lowest using weighted fitness scores. The difference in ranking observed between apple varieties demonstrates the care needed in predicting population performance in the field using single traits. [ABSTRACT FROM AUTHOR]

Trans-fatty acids (TFA) are geometric isomers of naturally occurring cis-fatty acids. High dietary TFA intake has been associated with risk factors for cardiovascular disease. However, little is known about TFA levels in humans. To address this data need, we developed and validated a new isotope dilution-gas chromatography-negative chemical ionization-mass spectrometry (ID-GC-NCI-MS) method for quantitation of 27 fatty acids (FA) including 4 major TFA in human plasma, serum, and red blood cells (RBC) from 66 donors. Quantitation was performed with 18 isotope labeled internal standards and results are presented in μM and % of total FA. This method has high sensitivity and specificity due to use of pentafluorobenzyl-bromide derivatization combined with NCI-MS and a 200 m column to optimize positional and geometric FA isomer separation. The four major TFA, palmitelaidic acid, elaidic acid, trans-vaccenic acid, and linoelaidic acid, were detected in all samples, with median total TFA concentrations of 17.7 μM in plasma, 19.6 μM in serum, and 21.5 μM in RBC. The % of total FA for the TFA was 0.20% in plasma, 0.20% in serum, and 0.30% in RBC. Patterns for % FA are similar to those reported in other studies. We developed a highly specific, ID-GC-NCI-MS method to quantitate TFA and other FA in humans. [ABSTRACT FROM AUTHOR]

A novel turn-on fluorescent probe containing a benzoxazole fluorophore has been synthesised and its response to different metal ions has been investigated by spectrometry. The probe was highly selective and sensitive to Zn2+and showed a complexation ratio towards Zn2+of 1:1. It also exhibited a linear response range for Zn2+from 0.3 to 4.8 μmol L–1 with a detection limit of 0.36 μmol L–1. [ABSTRACT FROM AUTHOR]

A simple chemosensor, namely, N -((quinolin-8-yl)methylene)acetohydrazide ( 1 ) was synthesized and used as an off–on fluorescence sensor, which exhibits high selectivity toward Zn 2 + in aqueous media. The probe has large Stokes shift of > 200 nm, and its detection limit for Zn 2 + is 89.3 nM. The binding process was confirmed through UV–vis absorption analysis, fluorescence measurements, mass spectroscopy study, 1 H NMR spectra and density functional theory calculation. The crystal structures of Zn 2 + , Ni 2 + , and Cu 2 + complexes based on 1 were determined through X-ray crystallographic analysis. The fluorescent probe was then applied to monitor intracellular Zn 2 + in HeLa cells. [ABSTRACT FROM AUTHOR]

A coumarin-based sensor C1 , namely 3-acetoacetylcoumarin was designed, synthesized and applied for hydrazine detection. Hydrazinolysis of the chemosensor gives a fluorescent coumarin-pyrazole product C1 − N 2 H 4 [3-(3-methyl-1H-pyrazol-5-yl)coumarin], and thus resulting in a prominent fluorescence off-on response toward hydrazine under physiological conditions. The probe is highly selective toward hydrazine over cations, anions and other biologically/environmentally abundant analytes. The detection limit of the probe is 3.2 ppb. The sensing mechanism was supported by 1 H NMR, IR, MS and DFT calculation. The application of the fluorescent probe in monitoring intracellular hydrazine in glioma cell line U251 was also demonstrated. [ABSTRACT FROM AUTHOR]

Dynamics of a PT -symmetry chain comprising split-ring resonator (SRR) dimers with both gain and loss are investigated. A dimer is built as a pair of opposite orientations of the SRR gaps which result in the alternating electric and magnetic coupling in the chain. The transition from the exact to the broken PT -symmetric phase is presented in the linear regime. Considering the Kerr nonlinearity, it is shown that the localized modes in the form of solitons exist in the continuum limit approximation. Such localized structures are studied in the phase plane and numerical expressions are also obtained. [ABSTRACT FROM AUTHOR]

Two porous metal-organic frameworks (MOFs) incorporating pentanuclear Yb(III) clusters and pyridyl-supported tetracarboxylates or pyridyl carboxylic acid-supported tetracarboxylates, Yb-DDPY and Yb-DDIA , are presented, in which the pentanuclear Yb(III) cluster shows uncommon trigonal bipyramidal geometry. Furthermore, the pentanuclear Yb(III) clusters are extended by tetracarboxylates to form a 3D porous framework with uniform M 12 L 8 -cages constructed by 12 pentanuclear Yb(III) clusters and 8 tetracarboxylates with the size of ca. 20 Å × 17 Å. Their highly CO 2 uptake capacity and the existence of Lewis acidic sites make these MOFs promising catalysts for the chemical conversion of CO 2 . These MOFs demonstrate good catalytic activities and recyclability in the cycloaddition of CO 2 and epoxides at 60 °C under 1.0 MPa pressure or at room temperature and atmospheric pressure. In addition, the synergistic effect of the Brønsted acidic –COOH groups and the Lewis acidic Yb(III) sites makes Yb-DDIA exhibit higher catalytic activity towards the cycloaddition of CO 2 and epoxides. [ABSTRACT FROM AUTHOR]

The present study investigated the role of echinocystic acid (EA) on the expression of nuclear factor (NF)-κB and cytochrome P450 1A1 (CYP1A1), and aortic morphology, in a rat model of hyperhomocysteinemia (Hhcy). A total of 50 Sprague Dawley rats were randomly divided into five groups as follows: Normal control (NC), model control (MC), vitamin control (VC; folic acid 1 mg/kg + vitamin B2 2 mg/kg + vitamin B12 10u g/kg), EA1 (20 mg/kg EA) and EA2 (40 mg/kg EA). Plasma homocysteine (Hcy) levels were determined via high performance liquid chromatography, and the morphology of the aorta was investigated using hematoxylin and eosin staining. Furthermore, aortic mRNA and protein levels of NF-κB and CYP1A1 were measured using reverse transcription-quantitative polymerase chain reaction analysis and western blotting, respectively. Plasma Hcy levels, and aortic mRNA and protein levels of NF-κB and CYP1A1, were significantly lower in the EA-treated group compared with the MC group (all P<0.05). However, the aortic morphology remained normal, including the endothelial cells of the inner layer, and smooth muscle cells of the media layer and adventitia. In conclusion, the results of the present study indicate that EA has a protective role on vascular endothelial cells in Hhcy through decreasing plasma Hcy, and thus NF-κB and CYP1A1 expression. [ABSTRACT FROM AUTHOR]

The precursors of SnO2 nanoparticles at different temperatures were synthesized by hydro-thermal method, and then SnO2 nanoparticles were obtained by calcination in this paper. Then the structure and micromorphology were characterized by X-ray Diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the chemical composition of the products were analyzed by infrared spectroscopy (IR) and ultraviolet visible diffuse reflectance spectroscopy (UV-vis DRS), finally, the photocatalytic degradation ability of prepared products were studied by ultraviolet absorption method. The results showed that the lowtemperature reaction is beneficial to the formation of particle products, and the calcined products were pure stannic oxide particles with rutile structure, which had good crystallinity, good dispersibility, uniform size and strong photocatalytic degradation ability. [ABSTRACT FROM AUTHOR]

A 2 × 2 factorial design was conducted to elucidate the effect of dietary biotin on growth performance, body composition, tissue lipid content and lipid metabolism related genes expression of blunt snout bream, Megalobrama amblycephala fed with different dietary lipid levels. Juvenile fish (average initial weight: 36.0 ± 1.0 g) were fed with diets containing two lipid levels (5% and 11%) and two biotin levels (0.06 mg kg − 1 and 2.50 mg kg − 1 ) for 8 weeks, respectively. Specific growth rate (SGR), hepatosomatic index (HSI), mesenteric fat index (MFI), hepatopancreas lipid, total triacylglycerol (TG) and cholesterol (TC) contents, plasma TG and muscle TG contents were significantly ( P < 0.05) affected by dietary lipid. No significant interactions between lipid and biotin were observed. Significant ( P < 0.05) interactions between lipid and biotin were observed in muscle lipid, hepatopancreas saturated fatty acids (SFA) and muscle EPA contents. Hepatopancreas monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and EPA + DHA contents were significantly ( P < 0.05) affected by dietary biotin. At dietary lipid levels of 5 or 10%, hepatopancreas MUFA contents were decreased but PUFA and EPA + DHA contents were increased significantly ( P < 0.05) with dietary biotin levels increase. Significant ( P < 0.05) interaction between lipid and biotin were also observed in hepatopancreas acetyl-CoA carboxylase α (ACCα), sterol regulatory element-binding protein 1 (SREBP1), acyl-CoA oxidase (ACO) and acyl-CoA oxidase (FACS) genes expression levels. ACCα, fatty acid synthetase (FAS), liver X receptor α (LXRα), SREBP1, ACO and FACS genes expression levels significantly ( P < 0.05) increased with the increasing dietary biotin levels. ACCα, peroxisome proliferatoractivated receptor α (PPARα), carnitine palmitoyltransferase I(CPTI) and ACO genes expression levels significantly ( P < 0.05) decreased with the increasing dietary lipid levels. In conclusion, no effects of biotin on growth performance, body parameter, whole-body composition in fish fed with 5% or 11% lipid diets were found. Dietary biotin could play a role in hepatopancreas fatty acid synthesis and β-oxidation related genes expression. Dietary biotin could promote hepatopancreas polyunsaturated fatty acids synthesis of fish. [ABSTRACT FROM AUTHOR]

Disentangling the evolutionary histories of polyploids, especially those with high ploidies, can reveal fundamental processes in speciation. Despite occurring frequently during evolution, the origins of many extant polyploid plant species remain largely unknown., By integrating linkage mapping, polyploid phylogeny and sex-determining region ( SDR) in a unified framework, we statistically evaluated evolutionary hypotheses concerning the origin of a recently recognized decaploid strawberry ( Fragaria cascadensis)., The maximum-likelihood phylogenies and topology tests across homeologous groups consistently rejected the seemingly parsimonious hypothesis of 'contemporary sympatric speciation' via hybridization between octoploid and diploid congeners. Instead, most chromosomes supported 'ancient hybrid speciation' between a maternal octoploid progenitor ancestral to extant octoploid strawberries and a paternal, extinct Fragaria iinumae-like diploid progenitor, probably in Beringia during the Pleistocene. The absence of a shared SDR between the decaploid and other Fragaria is also consistent with an older origin rather than a recent hybrid origin in situ., Our study reveals a long evolutionary history of the decaploid despite its recent discovery, and highlights the pitfalls of inferring polyploid origins from niche/range alone or combined with morphology. It can serve as an exemplary starting step towards building much-needed model systems of established polyploids that have been, and remain to be, recognized. [ABSTRACT FROM AUTHOR]

Previous studies have suggested that the Janus kinase (JAK)/signal transducers and activators of transcription (STAT) pathway is involved in hyperglycemia‑induced lung injury. The present study aimed to investigate the roles of suppressor of cytokine signaling3 (SOCS3) in the regulation of JAK2/STAT3 activation following high glucose (HG) treatment in A549 human pulmonary epithelial cells. Cell viability was evaluated using Cell Counting Kit-8 and lactate dehydrogenase assays. HG‑induced inflammatory injury in A549 cells was assessed through the evaluation of interleukin‑6 (IL‑6) and tumor necrosis factor‑α (TNF‑α) levels using ELISA. The protein expression levels of SOCS3, JAK2, STAT3, phosphorylated (p)‑JAK2 and p‑STAT3 were determined using western blot analysis. Cellular viability was significantly decreased, whereas IL‑6 and TNF‑α levels were significantly increased, following HG stimulation of A549 cells. In addition, the protein levels of SOCS3, p‑JAK2 and p‑STAT3 were significantly increased in HG‑treated cells. Treatment with the JAK2/STAT3 inhibitor tyrphostin AG490, or SOCS3 overexpression, appeared to prevent the HG‑induced alterations in protein expression. Furthermore, cellular viability was enhanced, whereas the levels of proinflammatory cytokines were suppressed. These finding suggested the involvement of the SOCS3/JAK2/STAT3 signaling pathway in HG‑induced responses in lung cells. Therefore, it may be hypothesized that the inhibition of the JAK2/STAT3 pathway through SOCS3 overexpression may prevent hyperglycemia‑induced lung injury, and may have therapeutic potential for the treatment of patients with diabetic lung injury. [ABSTRACT FROM AUTHOR]

Sodium hydroxide (NaOH) has been an indispensable additive in the selective aerobic oxidation of alcohols/polyols in water for ketone and carboxylic acid syntheses over supported metal catalysts, including Au, though the exact function of NaOH remains far from clear. We disclose here that NaOH alone can independently serve as a homogeneous catalyst for the oxidation reactions. This conclusion is supported by rigorous investigations of the effects of NaOH alone (without the presence of any metal catalyst) on the reactivity of aqueous glycerol, ethylene glycol, 2-propanol, and ethanol and their product distribution. Computational results based on density functional theory are also provided to explain the experimentally measured reactivity order of the various alcohols and to generate insight into the molecular mechanisms for the oxidation reactions. Besides challenging existing knowledge about the function of NaOH in alcohol oxidation reactions, this study opens a new avenue for catalytic alcohol/polyol upgrading. [ABSTRACT FROM AUTHOR]

A 8-week feeding trial was conducted to evaluate the effect of different berberine-dietary feeding modes on growth, non-specific immune responses and disease resistance of blunt snout bream, Megalobrama amblycephala . Fish (average initial weight 4.70 ± 0.02 g) were fed two fat levels (5% and 10%) diets in three berberine-feeding modes (supplementing 50 mg/kg berberine continuously, two-week or four-week intervals) with four replicates, respectively. Then, fish were challenged by Aeromonas hydrophila and mortality was recorded for the next 96 h after feeding trial. The results showed that different feeding modes of berberine significantly influenced growth, innate immunity and antioxidant capability of fish. Fish fed normal diet with 50 mg/kg berberine at two-week interval mode reflected remarkably ( P < 0.05 ) high weight gain (WG). Plasma TC and TG contents were significantly ( P < 0.05 ) decreased. The lysozyme (LYZ) activities, complement component 3 (C3) and complement component 4 (C4) concentrations were significantly ( P < 0.05 ) increased. Fish not only exhibited relatively low hepatopancreas malondialdehyde (MDA) and lipid peroxide (LPO) contents, but also significantly ( P < 0.05 ) improved superoxide dismutase (SOD) and catalase (CAT) activities. Fish mortality after challenged by Aeromonas hydrophila was decreased. Same results were also presented in fish fed high-fat diet with 50 mg/kg berberine at two-week, four-week intervals or continuous feeding modes. Based on fish healthy improvement and feeding cost saving, blunt snout bream fed normal diet with 50 mg/kg berberine at two-week interval or fed high-fat diet with berberine at two-week or four-week intervals were optimal feeding mode, respectively. [ABSTRACT FROM AUTHOR]

Social media provides customers with great opportunities to share their opinions regarding certain products and services. Comparative text, as an important expression form, deserves further exploration, since it contains considerable comparative information between different products and services. In this study, we review existing research on Comparative Text Mining (CTM) in the past 16 years. Basic concepts related to CTM are first described, and a general research framework is subsequently proposed. We then dive into each component of the research framework, ranging from data acquisition, comparative text identification (CTI), comparative relation extraction (CRE), to potential applications. In addition, we conduct extensive experimental analysis on existing methods for CTI and CRE, and clarify their limitations. Accordingly, we provide corresponding insights, and point out future research directions. [ABSTRACT FROM AUTHOR]

The microenvironments of biological systems are associated with the pathology of organisms. This study, aimed to construct a hemicyanine-based probe (1), which can respond to mitochondrial viscosity and hydrazine (N 2 H 4), for imaging application in living cells and zebrafish. The probe showed no fluorescence due to the intramolecular rotation in the solution; however, it exhibited a strong emission at 730 nm when the molecules were restricted to a high-viscosity environment. The addition of N 2 H 4 caused an elimination reaction of the N-substituted group in the pyridinium part and further broke the C C bond to produce a highly fluorescent hydrazone. Also, the probe could selectively and quantitatively detect N 2 H 4 via the fluorescence enhancement at 510 nm in a concentration range of 0 μM–140μM, with the limit of detection being 0.0485 μM. This probe may be used to study diseases related to N 2 H 4 and viscosity changes in biological systems. Furthermore, the analysis methods based on probe 1 for N 2 H 4 detection in soil, water, and air samples were successfully established. [Display omitted] • A dual˗emission fluorescent probe toward N 2 H 4 and viscosity was developed. • The probe exhibited a maximum emission peak at 730 nm for detecting viscosity. • The probe responded to N 2 H 4 via the fluorescence enhancement at 510 nm with the limit of detection being 0.0485 μM. • Analysis methods based on the probe for N 2 H 4 detection in soil, water and air samples have been established. • The probe has been successfully used for monitoring mitochondrial N 2 H 4 and viscosity in the cells and zebrafish. [ABSTRACT FROM AUTHOR]

Exploitation of NiCo 2 O 4 -based novel composite electrode materials with enhanced comprehensive properties is essential for high-performance supercapacitors. Herein, ultrathin NiCo 2 O 4 nanosheets wrapped carbon nanoplates (NiCo 2 O 4 @CNPs) are fabricated by co-precipitation method and subsequent thermal annealing treatment. Characterization results indicate that 2D leaf-like NiCo 2 O 4 @CNPs is synthesized and NiCo 2 O 4 nanosheets with thickness of 4 nm are tightly wrapped on CNPs. The NiCo 2 O 4 @CNPs is possessed of enhanced electrochemical properties in comparison to bare CNPs, bare NiCo 2 O 4 and other NiCo 2 O 4 -based materials reported in literatures. The NiCo 2 O 4 @CNPs electrode shows higher specific capacitance (1265 F g−1 at 1 A g−1) and remarkable rate capability. Furthermore, the NiCo 2 O 4 @CNPs electrode has excellent cycling stability, and 97.3% of the initial specific capacitance still remains after 2000 cycles. Reasons for the enhanced electrochemical properties of NiCo 2 O 4 @CNPs were analyzed. In addition, the supercapacitor of NiCo 2 O 4 @CNPs//NiCo 2 O 4 @CNPs displays a high energy density of 32.4 Wh kg−1 at 435 W kg−1 and a high power density of 8676 W kg−1 at 14.4 Wh kg−1. The above results manifested that NiCo 2 O 4 @CNPs is an potential electrode material for fabricating high-performance supercapacitor. [Display omitted] • NiCo 2 O 4 nanosheets with thickness of 4 nm were tightly wrapped on CNPs. • NiCo 2 O 4 @CNPs showed excellent performances as electrode material for supercapacitor. • Supercapacitor of NiCo 2 O 4 @CNPs//NiCo 2 O 4 @CNPs showed high energy and power density. • Reasons for the enhanced electrochemical properties of NiCo 2 O 4 @CNPs were analyzed. [ABSTRACT FROM AUTHOR]

In this study, three types of rectangular pool fires with the same equivalent area were conducted in a simulated cargo compartment to investigate the effects of sidewall distance and ambient pressure on fire behavior. Three dimensionless distances ( λ = 0 , λ = 0.25 , and λ = 0.25 ) and three ambient pressures (50 kPa, 76 k Pa, 101 kPa) were used in the experiments. The results showed that the sidewall had a significant impact on the burning of n-heptane pool fires, with the flame height increasing as the sidewall distance decreased and lower ambient pressure intensifying this trend. The shape of the flame also directly affected the sidewall temperature, which showed a different trend in different test cases due to the combined effect of air entrainment limitation and radiation enhancement from the flame. In addition, models for calculating the burning rate and flame height were developed by modifying classical models using the dimensionless distance λ , entrainment coefficient EF , and equivalent diameter D eq . [ABSTRACT FROM AUTHOR]

A novel hollow hierarchical nano-heterostructure consisting of ZnO nanorods coated with In 2 O 3 nanoparticles was prepared using a hydrothermal method combined with an annealing treatment via carbon fiber (CF) templates. Experimental results reveal that the In 2 O 3 /ZnO hierarchical composite has a tubular structure with an average diameter of ∼6 μm and In 2 O 3 nanoparticles distribute uniformly on the ZnO nanorods. Significantly, the obtained heterostructure shows enhanced visible light photoactivity to methyl orange (MO) degradation and good selectivity and response toward ethanol even at a low detection limit (1 ppm). This outstanding performance is a result of the one-dimensional tubular structure and the heterostructure formation between In 2 O 3 and ZnO, advantageous for the adsorption and diffusion and the separation of electrons and holes. In addition, the excellent performance is greatly improved by virtue of the evenly decorated In 2 O 3 nanoparticles on the ZnO nanorod surfaces, which provide more active sites for pollutants and gases. [ABSTRACT FROM AUTHOR]

Mechanical failure of well cement sheath can result in loss of zonal isolation, which is the cause of many problems, such as sustainable casing pressure, crossflows between formation zones, and leakage of fluid to surface. Pressure- and temperature-induced stresses in the cement sheath have been numerically analyzed by a number of previous investigators with sophisticated computer models. However, these investigations do not provide a practical method for predicting the maximum permissible pressure limited by the mechanical failure of cement sheath. An analytical model was derived in this work to predict the Maximum Permissible Pressure (MaxPP) in fluid injection and well stimulation. Results given by the model were verified with data from a CO 2 sequestration operation. Case studies with the model suggest that if the cement placement efficiency in the annulus is 100% as detected by CBL, formation in-situ stress should be utilized to make a conservative prediction of the MaxPP. If the cement placement efficiency in the annulus is less than 100% detected by CBL, the outer radius of the cement sheath should be considered and formation pore pressure in the cap rock should be employed to make a conservative prediction of the MaxPP. Improving cement strength is not an effective means of increasing MaxPP. The MaxPP should be enhanced by maximizing the outer radius of the cement sheath through improving the cement placement efficiency. The Maximum Permissible Net Pressure is lower than the burst-pressure rating of casing, suggesting that cement sheath failure will occur before casing failure occurs in the burst condition. Therefore burst design should be carried out for cement sheath, not production casing. This paper provides engineers a practical guideline to design and apply fluid injection pressure in well stimulation and operations. [ABSTRACT FROM AUTHOR]

The present studies focus on mechanical properties and microstructure evolution of a Fe-15Mn dual phase alloy during tensile deformation based on the analyses of X-ray diffraction, electron back-scattered diffraction and transmission electron microscopy. The alloy possesses excellent combination of strength and ductility (UTS×TEL=32 GPa•%) and good strain hardening capacity owing to several plastic deformation mechanisms. At earlier stage of tensile deformation, the deformation induced transformation from γ to ε is the main plastic deformation mechanism. In addition, the deformation induced twins within ε-martensite and transformation from ε to αˊ also have contributions to the plastic deformation. With further increasing the strain, the deformation induced transformation from ε→αˊ in combination with the dislocation slip in γ, ε and αˊ become the main plastic deformation mechanisms. During the whole tensile deformation, nearly all αˊ-martensite grains exist within ε-martensite plates, indicating that the deformation induced transformation sequence is ε→αˊ. Moreover, it has been demonstrated that the αˊ-martensite is preferred to nucleate at intersections of two ε-martensite plates, interfaces of γ/ε and ε/ε and low angle grain boundaries within ε-martensite plates. Note that the orientations of some αˊ-martensite grains existing within the same ɛ-martensite plate are not exactly the same. [ABSTRACT FROM AUTHOR]

Dynamics of a chain of split-ring resonator dimers with Kerr nonlinear interaction are investigated. A dimer is built as a pair of coupled split-ring resonators with different size. It is shown that the gap solitons with frequency lying in the gap exist due to the interaction of the discreteness and nonlinearity. Such localized structures are studied in the phase plane and analytical and numerical expressions are also obtained. [ABSTRACT FROM AUTHOR]

RATIONALE: Endocrine-disrupting chemicals (EDCs) in environment samples and food stuffs are an increasing serious public health issue due to their potency to interfere and deregulate several aspects of the endocrine system. Because of their extremely low abundance, it remains a challenging task to develop a sensitive detection method. METHODS: 4'-Carbonyl chloride rosamine (CCR) was used as a derivatization reagent for EDCs for the first time. A new ultrasound-assisted in situ derivatization/dispersive liquid-liquid microextraction (UA-DLLME with in situ derivatization) method for multiple EDCs including five estrogens, two alkylphenols, eight bisphenols, seven parabens and triclosan coupled with ultra-high-performance liquid chromatography/tandem mass spectrometry (UHPLC/MS/MS) has been developed and validated. RESULTS: The ionization efficiency ofEDCswasgreatly enhanced through the introduction of a permanent chargedmoiety of CCR into the derivatives during electrospray ionization (ESI)-MS analysis. The main variables potentially affecting the UA-DLLME with in situ derivatization process are optimized. The recoveries and matrix effects of 23 EDCs for the spiking samples were in the range of 83.0-116.0% and 85.8-114.6%, respectively. Good method reproducibility was achieved. CONCLUSIONS: The limits of detection (LODs) for 23 EDCs were 0.05-0.40 ng/L and 0.03-0.25 ng/g (dry weight, d.w.) for environment samples and food stuffs, respectively. The proposed method has been demonstrated to be suitable for simultaneous determination of multiple EDCs in real samples with high sensitivity, speediness, and good sample clean-up ability. [ABSTRACT FROM AUTHOR]